The DOI matches its Crossref record; 53 of the 55 references it cites were found in a registry or an index; none of the 91 sources its claims cite is checked for support yet.
Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo
Open accessAbstract
MicroRNAs (miRNAs) are small, noncoding RNAs that play a critical role in developmental and physiological processes and are implicated in the pathogenesis of several human diseases, including cancer. They function by regulating target gene expression post-transcriptionally. In this study, we examined the role of oncogenic mir-21 in the pathogenesis of glioblastoma, the most aggressive form of primary brain tumor. We have previously reported that mir-21 is expressed at higher levels in primary glioblastoma-tissue and glioblastoma-derived cell lines than in normal brain tissue. We demonstrate that downregulation of mir-21 in glioblastoma-derived cell lines results in increased expression of its target, programmed cell death 4 (Pdcd4), a known tumor-suppressor gene. In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastoma-derived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar. Using a glioblastoma xenograft model in immune-deficient nude mice, we observe that glioblastoma-derived cell lines in which mir-21 levels are downregulated or Pdcd4 is over-expressed exhibit decreased tumor formation and growth. Significantly, tumors grow when the glioblastoma-derived cell lines are transfected with anti-mir-21 and siRNA to Pdcd4, confirming that the tumor growth is specifically regulated by Pdcd4. These critical in vivo findings demonstrate an important functional linkage between mir-21 and Pdcd4 and further elucidate the molecular mechanisms by which the known high level of mir-21 expression in glioblastoma can attribute to tumorigenesis--namely, inhibition of Pdcd4 and its tumor-suppressive functions.
Overview
AI snapshot
Written from the paper’s full text.
TL;DR
In glioblastoma-derived cell lines and primary tumors, high miR-21 is inversely associated with the tumor suppressor Pdcd4; inhibiting miR-21 or overexpressing Pdcd4 reduces proliferation, increases apoptosis, and suppresses anchorage-independent growth. In nude-mouse xenografts, anti-miR-21 or Pdcd4 overexpression reduces tumor growth, and siRNA against Pdcd4 reverses the anti-miR-21 effect, supporting Pdcd4 as a key mediator.
Key findings
- miR-21 was elevated in all 7 glioblastoma-derived cell lines and all 13 glioblastoma tumors examined, while Pdcd4 protein was undetectable in primary glioblastoma tissues and cell lines compared with normal brain. Anti-miR-21 transfection increased Pdcd4 protein at 24, 48, and 72 hours.
- Anti-miR-21 treatment decreased proliferation, increased TUNEL-positive apoptosis, increased G0/G1 and decreased S-phase fraction, and reduced soft-agar colony formation by 65% (10 mM anti-miR-21) and 75% (30 mM anti-miR-21) in 3 independent experiments; U251 and U87 cells treated with anti-miR-21 formed 70% and 60% fewer colonies, respectively.
- Pdcd4 overexpression increased apoptosis and decreased colony formation. Anti-miR-21 plus Pdcd4 siRNA restored colony numbers similar to untreated controls; cells treated with anti-miR-21 and Pdcd4 siRNA produced 85% of the colonies seen with anti-miR-21 alone.
- In xenografts, anti-miR-21 reduced tumor growth by 30% at day 30 (P = .01); Pdcd4 overexpression produced a 90% decrease (P = .001) or complete lack of tumor growth. In 5 independent xenograft experiments, only 5 of 24 U251 GFP+Pdcd4 and 6 of 24 U87 GFP+Pdcd4 mice developed detectable tumors by day 30, and these were on average 90% smaller. Anti-miR-21 plus Pdcd4 siRNA tumors grew comparably to controls, reaching 1.5 cm³ by day 30. Pdcd4 was undetectable in 4 individual tumors arising from Pdcd4-overexpressing lines.
Methods
- Glioblastoma-derived cell lines SNB19, U251, U87, and SF767 were used with primary glioblastoma and normal brain samples. Stable Pdcd4-expressing polyclonal and monoclonal cultures were derived; transient transfections used anti-miR-21, negative/toxicity control, and Pdcd4 siRNA. Assays included Northern blot, Western blot, stem-loop real-time PCR, proliferation counts, TUNEL apoptosis, cell-cycle flow cytometry, and soft-agar colony formation.
- Xenografts used female 4–6-week-old Nude-Foxn1 nu mice injected subcutaneously in the flank with 5 × 10⁶ cells. Tumor size was measured in 3 dimensions, volume calculated as ellipsoid, and tumors imaged with the IVIS 200 Xenogen system. Data were from 5 independent xenograft experiments (total n = 24 animals per condition); statistics used unpaired two-tailed Student t test with P < .05, and experiments were performed at least 3 times.
Limitations
- Stated: xenografts were not of sufficient size to analyze DNA, RNA, and protein, so only Pdcd4 protein was measured. The authors note that rare cells may escape Pdcd4 inhibition through altered transgene integration or epigenetic inactivation, and small tumors from anti-miR-21-treated cells may arise from untransfected cells. They also note miR-21 can target several genes; anti-miR-21 plus Pdcd4 siRNA still produced 85% of colonies compared with anti-miR-21 alone, suggesting additional miR-21 targets.
- Evident: the in vivo work uses subcutaneous xenografts in immune-deficient nude mice rather than orthotopic or patient-derived models, and no survival or clinical outcome data are reported. Transfection efficiency was 80%–90%, leaving potential untransfected cells in treated populations.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
0 of 91 cited sources checked · 0 supported · 0 flagged
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Also, TUNEL staining revealed enhanced apoptosis in U251 (Fig. 3B) and U87 cells (data not shown) treated with anti-mir-21, compared with cells cultured in either medium alone or with NS control.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Western blot analyses of nuclear proteins isolated from these same U251 and U87 cultures exhibited increased Pdcd4 protein levels 24, 48, and 72 h after anti-mir-21 treatment (Fig. 2B, lanes 3 -5 and 8-10, respectively).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Increased apoptosis in U87 cells treated with anti-mir-21 or stably over expressing Pdcd4 (U87 Pdcd4 ) was also observed (data not shown).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The U251 Pdcd4 polyclonal cell culture showed a decrease in colony number compared to cells that did not have elevated Pdcd-4 levels.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
“Also, TUNEL staining revealed enhanced apoptosis in U251 (Fig. 3B) and U87 cells (data not shown) treated with anti-mir-21, compared with cells cultured in either medium alone or with NS control.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We demonstrate that downregulation of mir-21 in glioblastoma-derived cell lines results in increased expression of its target, programmed cell death 4 (Pdcd4), a known tumor-suppressor gene.”
- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · plain
“Western blot analyses of nuclear proteins isolated from these same U251 and U87 cultures exhibited increased Pdcd4 protein levels 24, 48, and 72 h after anti-mir-21 treatment (Fig. 2B, lanes 3 -5 and 8-10, respectively).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
“We observed decreased cell numbers in cultures treated with anti-mir-21, compared with cultures that were incubated in regular media or transfected with a nonspecific negative toxicity control (Fig. 3A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
“The U251 Pdcd4 polyclonal cell culture showed a decrease in colony number compared to cells that did not have elevated Pdcd-4 levels.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Clonal isolates and a polyclonal culture of U251 overexpressing Pdcd-4, U251 Pdcd4 demonstrated increased spontaneous apoptosis, as determined by TUNEL staining, compared with the parental cells from which they were derived (Fig. 3B and C).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We observed decreased cell numbers in cultures treated with anti-mir-21, compared with cultures that were incubated in regular media or transfected with a nonspecific negative toxicity control (Fig. 3A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesNone of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“We have previously reported that mir-21 is expressed at higher levels in primary glioblastoma-tissue and glioblastoma-derived cell lines than in normal brain tissue.”
- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · plain
“Elevated levels of mir-21 were observed in all 7 glioblastoma-derived cell lines and in all 13 glioblastoma tumors we examined (Fig. 1) (data not shown).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
What the sources say
- Not matchedcites [8]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [18]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
“Clonal isolates and a polyclonal culture of U251 overexpressing Pdcd-4, U251 Pdcd4 demonstrated increased spontaneous apoptosis, as determined by TUNEL staining, compared with the parental cells from which they were derived (Fig. 3B and C).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In 3 independent experiments, the number of colonies formed following exposure to anti-mir-21 decreased by 65% (10 mM anti-mir-21) and 75% (30 mM anti-mir-21).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“U251 GFP or U87 GFP lines transfected with anti-mir-21 demonstrated decreased tumor growth in vivo (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Mice that received cell lines overexpressing Pdcd4, U251 GFP+Pdcd4 , or U87 GFP+Pdcd4 also had tumors that were reduced in size, compared with tumors arising in animals injected with the same cells bearing only GFP and not overexpressing Pdcd4 (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In that analysis we found a significant inverse correlation (P ¼ .004) between miR-21 and Pdcd4 protein expression levels (data not shown) similar to the data described above in Fig. 2A and B that demonstrated undetectable levels of Pdcd4 protein in glioblastoma-derived cell lines that expressed high levels of mir-21 and vice-versa.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Northern blot analyses demonstrated decreased levels of mir-21 in U251 and U87 cells 24, 48, and 72 h after transfection with anti-mir-21 (Fig. 2A, lanes 3-5 and 8 -10).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“U251 cells treated with anti-mir-21 for 72 h and plated in soft agar displayed decreased anchorage-independent growth and formed fewer colonies (Fig. 4A and B) when compared to controls.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Significantly, tumors grow when the glioblastoma-derived cell lines are transfected with anti-mir-21 and siRNA to Pdcd4, confirming that the tumor growth is specifically regulated by Pdcd4.”
- Also stated in: § Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4 · plain
“More importantly, animals that received U251 GFP or U87 GFP lines after transfection with anti-mir-21 and siRNA to PDCD4 gave rise to tumors that developed to 1.5 cm 3 in size by day 30, comparable to the tumors that developed from the control, untreated glioblastoma-derived cell lines (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4 · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Having observed an inverse correlation between mir-21 and Pdcd4 protein levels (Fig. 1A and B)”
- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · boosted
“In that analysis we found a significant inverse correlation (P ¼ .004) between miR-21 and Pdcd4 protein expression levels (data not shown) similar to the data described above in Fig. 2A and B that demonstrated undetectable levels of Pdcd4 protein in glioblastoma-derived cell lines that expressed high levels of mir-21 and vice-versa.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression · boosted
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, our data indicate that either downregulation of mir-21 or overexpression of its target, Pdcd4, in glioblastomaderived cell lines leads to decreased proliferation, increased apoptosis, and decreased colony formation in soft agar.”
- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
“U251 cells treated with anti-mir-21 for 72 h and plated in soft agar displayed decreased anchorage-independent growth and formed fewer colonies (Fig. 4A and B) when compared to controls.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Also stated in: § Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“By use of Western blot analysis, we observed that Pdcd4 protein levels are undetectable in primary glioblastoma tissues (Fig. 1B, lanes 1 -4) and glioblastoma-derived cell lines (Fig. 1B, lanes 5 -8), compared with normal human brain samples (Fig. 1B, lanes 9 -10).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Compared with cells that were treated with anti-mir-21 only, U251 or U87 that were treated with anti-mir-21 and siRNA to Pdcd4 produced higher number of colonies, similar to those formed by untreated U251 or U87 (Fig. 4A and B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the 5 independent xenograft experiments we performed examining U251 GFP+Pdcd4 or U87 GFP+Pdcd4 , only 5 of 24 and 6 of 24 mice, respectively, developed tumors detectable by day 30.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“More importantly, animals that received U251 GFP or U87 GFP lines after transfection with anti-mir-21 and siRNA to PDCD4 gave rise to tumors that developed to 1.5 cm 3 in size by day 30, comparable to the tumors that developed from the control, untreated glioblastoma-derived cell lines (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“U251 or U87 cells treated for 72 h with anti-mir-21 formed 70% and 60% fewer colonies, respectively, than did control cells.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“we were able to measure Pdcd4 protein levels and found that Pdcd4 levels were undetectable by Western blot analysis of 4 individual tumors that arose from animals injected with U251 GFP+Pdcd4 or U87 GFP+Pdcd4 lines (Fig. 5D).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Mice that received cell lines overexpressing Pdcd4, U251 GFP+Pdcd4 , or U87 GFP+Pdcd4 also had tumors that were reduced in size, compared with tumors arising in animals injected with the same cells bearing only GFP and not overexpressing Pdcd4 (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, U251 Pdcd4 and U87 Pdcd4 cell lines were also examined and demonstrated a decrease in number of colonies formed in soft agar, compared with cells that did not have elevated Pdcd-4 levels (Fig. 4A and 4B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In all of these experiments, tumor growth was reduced by 30% at day 30 (P ¼ .01) in mice that were injected with anti-mir-21-transfected U251 GFP or U87 GFP cells.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Furthermore, hematoxylin and eoisin staining of tumors (Supplemental Fig. S1) that arose from untreated U251 or U87 or U251 or U87 cell lines transfected with NS control or anti-mir-21 or with anti-mir-21 and siRNA to PDCD4 show similar morphological features of glioblastoma and are indistinguishable from one another.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These tumors were, on average, 90% smaller than the tumors that arose after injection with untreated or nonspecific negative/toxicity control treated U251 GFP or U87 GFP cells (data not shown).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“U251 GFP or U87 GFP lines transfected with anti-mir-21 demonstrated decreased tumor growth in vivo (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the fact that some tumors, albeit much smaller than those formed in the control groups, did develop in U251 GFP+Pdcd4 -or U87 GFP+Pdcd4 -derived xenografts provided an opportunity to examine Pdcd4 levels in such tumors (Fig. 5D).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Similarly, we saw an 90% (P ¼ .001)decrease in tumor size or complete lack of tumor growth in mice that were injected with Pdcd4 over-expressing U251 GFP+Pdcd4 or U87 GFP+Pdcd4 cells.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Mice that received U251 GFP or U87 GFP lines after transfection with anti-mir-21 and siRNA to PDCD4 significantly gave rise to tumors that were comparable to the untreated controls (Fig. 5A and 5C), confirming that the tumor growth is specifically regulated by PDCD4 and represents a crucial functional linkage between mir-21 and PDCD4 in vivo.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Furthermore, by assessing endogenous Pdcd4 protein levels in glioblastoma-derived cell lines (Fig. 1B) and in lines in which endogenous mir-21 expression had been inhibited (Fig. 2A and B), we determined that inhibition of mir-21 in glioblastoma-derived cell lines resulted in enhanced Pdcd4 expression.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, glioblastoma-derived cell lines in which mir-21 levels were inhibited displayed decreased anchorage-independent growth (Fig. 4A and B), whereas glioblastoma-derived cell lines expressing Pdcd4 showed increased apoptosis and diminished anchorage-independent growth (Fig. 4A and B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesThe paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Interestingly, cells treated with anti-mir-21 and siRNA to Pdcd4 produced 85% of the colonies compared to cells treated with anti-mir-21 only.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We observed that cells treated with anti-mir-21 had decreased proliferation (Fig. 3A) and also exhibited enhanced apoptosis, compared with untreated cells (Fig. 3B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, glioblastoma-derived cell lines in which mir-21 levels were inhibited displayed decreased anchorage-independent growth (Fig. 4A and B), whereas glioblastoma-derived cell lines expressing Pdcd4 showed increased apoptosis and diminished anchorage-independent growth (Fig. 4A and B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Compared with cells treated with anti-mir-21 only, cells that were treated with anti-mir-21 and siRNA to Pdcd4 produced an increased number of colonies similar to those formed by untreated controls (Fig. 4A and B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We observed that cells treated with anti-mir-21 had decreased proliferation (Fig. 3A) and also exhibited enhanced apoptosis, compared with untreated cells (Fig. 3B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Importantly, Pdcd4 was undetectable in the few, small tumors that did develop from the Pdcd4 overexpressing lines.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We observed that glioblastomaderived cell lines in which mir-21 expression had been inhibited formed fewer tumors and smaller tumors (Fig. 5A) than those that arose after injection of untreated control cell lines.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The high level of mir-21 expression in human glioblastoma-derived cell lines and glioblastoma primary tumors, compared with that observed in normal brain tissue, suggested its potential in contributing to the malignant behavior of glioblastoma (Fig. 1A and C).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, glioblastoma-derived cell lines in which mir-21 levels were inhibited displayed decreased anchorage-independent growth (Fig. 4A and B), whereas glioblastoma-derived cell lines expressing Pdcd4 showed increased apoptosis and diminished anchorage-independent growth (Fig. 4A and B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We observed that glioblastomaderived cell lines in which mir-21 expression had been inhibited formed fewer tumors and smaller tumors (Fig. 5A) than those that arose after injection of untreated control cell lines.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“further elucidate the molecular mechanisms by which the known high level of mir-21 expression in glioblastoma can attribute to tumorigenesis-namely, inhibition of Pdcd4 and its tumor-suppressive functions.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“confirming that the tumor growth is specifically regulated by Pdcd4.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These data are consistent with the regulation of Pdcd-4 by mir-21.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the inverse correlation between mir-21/Pdcd4 levels (Fig. 2A and B) strongly suggests that mir-21 regulates Pdcd4.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These critical in vivo findings demonstrate an important functional linkage between mir-21 and Pdcd4”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesNone of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4 has a binding site for mir-21 11,12”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Although glioblastomas harbor diverse oncogenes and mutated tumor-suppressor genes whose pattern of alteration and expression varies considerably from tumor to tumor, 20 most glioblastomas examined to date have high levels of mir-21 expression.11 -14,18”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [18]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Not matched
In the paper
“Recently, mir-21 was shown to regulate Pdcd4 in glioblastoma.18”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [18]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Normal brain tissue expresses Pdcd4.19,26,27”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
What the sources say
- Not matchedcites [19]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [26]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [27]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Not matched
In the paper
“conversely, Pdcd4 has been shown to be pro-apoptotic.24”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
What the sources say
- Not matchedcites [24]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4, a known tumor suppressor gene, has been identified as a functional target of mir-21.16,17”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [17]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4, a known tumor suppressor gene, has been identified as a functional target of mir-21.16,17”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [17]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Load-bearingStrength:boosted· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Mir-21 has been shown to act as an anti-apoptotic factor in glioblastoma-derived cell lines, 11,12”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Although an additional major pathway of Pdcd4 inactivation is the increased proteasomal degradation of Pdcd4 due to its phosphorylation by Akt and p70(S6K), 46 our findings provide strong evidence that, by inhibition of Pdcd4 by mir-21, over-expression contributes to glioblastoma growth.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Similarly, the small tumors formed by anti-mir-21-treated cells were probably formed by a fraction of glioblastoma-derived cells that had not been transfected in vitro by synthetic anti-mir-21 prior to their injection into mice.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The finding that Pdcd4 protein levels were not detectable (Fig. 5D) is strong evidence that these tumors were formed by cells not expressing Pdcd4.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Strength:boosted· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The high level of mir-21 expression in human glioblastoma-derived cell lines and glioblastoma primary tumors, compared with that observed in normal brain tissue, suggested its potential in contributing to the malignant behavior of glioblastoma (Fig. 1A and C).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“More importantly, we verified that the decreased tumor growth was predominantly a result of Pdcd4 being downregulated by mir-21.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesNone of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4, a described target of mir-21, 16 -18 has been characterized as both a tumor suppressor 16,21 -25 and a pro-apoptotic gene that may function by binding eukaryotic initiation factor 4A (eIF4A) and inhibiting translation initiation.38 -40”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [21]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [22]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [23]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [24]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [25]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“More importantly, because mir-21 can target several genes, 10,11 we sought to determine whether the biologic effects we observed following mir-21 inhibition were a consequence of Pdcd4 inhibition.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [10]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“A possible explanation for this finding is that mir-21 also inhibits other genes contributing to the malignant characteristics of glioblastoma-derived cells 47,48 .”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [47]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [48]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4, a described target of mir-21, 16 -18 has been characterized as both a tumor suppressor 16,21 -25 and a pro-apoptotic gene that may function by binding eukaryotic initiation factor 4A (eIF4A) and inhibiting translation initiation.38 -40”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [17]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [18]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Also, mir-21 may play an oncogenic role in glioblastoma acting as an antiapoptotic factor.11 -15”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [15]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Not matched
In the paper
“The combined treatment of glioblastoma with an miR-21 antagonist and pathotropic neural precursor cell -mediated delivery of tumor necrosis factor-related apoptosis -inducing ligand (TRAIL) to glioblastoma in vivo resulted in a significant reduction in tumor xenograft growth in mice.14”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Not matched
- It may state two separate claims as one. 15
- Probably not a substantial claim. 19
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We also observed decreased numbers of colonies formed by U87 cells that were treated with anti-mir-21 or stably over-expressed Pdcd4 (U87 Pdcd4 ) (Fig. 4B).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Subcutaneous injection of 5 × 10 6 cells from U251 GFP or U87 GFP in the flank of immunosuppressed mice gave rise to tumors that were first palpable by day 7 after injection and that developed to 1.5 cm 3 in size by day 30.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“High cellularity and microvascular prolifer- ation (Supplemental Fig. S1) and the presence of necrosis (Supplemental Fig. S2), all of which are defining features of glioblastoma, are evident in these tumors.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In these in vivo experiments mice that received cell lines overexpressing Pdcd4 showed a substantial decrease in tumor size and/or complete ablation of tumor growth (Fig. 5A).”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“In addition to being a pro-apoptotic gene, Pdcd4 is a suppressor of malignant transformation and tumor progression and has been shown to inhibit invasion and intravasation by tumor cells.16,22 -25”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Downregulation of mir-21 or Overexpression of Pdcd4 Results in Reduction of Glioblastoma Xenograft Growth that is Reversed by siRNA to Pdcd4
What the sources say
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [22]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [23]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [24]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [25]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We routinely achieved 80% -90% transfection efficiency.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Down Regulation of mir-21 Expression in Glioblastoma-Derived Cell Lines Results in Enhanced Pdcd4 Expression
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“MiR-21 has been identified as one of the most commonly overexpressed miRNAs in solid tumors.9,10”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [9]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [10]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Glioblastomas are the most malignant brain tumors of glial origin.21,28”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [21]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [28]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Previous work in our laboratory 8 and by others 9 -14 has demonstrated that miR-21 is a member of a class of miRNAs that are frequently overexpressed in solid tumors and may contribute to oncogenesis.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [8]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [9]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [10]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Low levels of mir-21 are expressed in grade II and grade III gliomas, whereas higher levels are observed in glioblastoma.13,15”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [15]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
- Not matched
In the paper
“because mir-21 can potentially target several genes, 11”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Inhibiting mir-21 expression in glioblastoma-derived cell lines results in decreased proliferation, increased apoptosis, and diminished anchorage-independent growth
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“All of the experiments were performed at least 3 times.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Statistical Analysis
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“They are also among the most resistant of all human tumors to available modalities of treatment, perhaps because of their genetic heterogeneity and invasiveness.28”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [28]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“In glioblastoma, mir-21 is overexpressed, and its expression correlates with glioma grade.8,10 -15”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > M
What the sources say
- Not matchedcites [8]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [10]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [15]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Mice that received U251 GFP or U87 GFP lines after transfection with anti-mir-21 and siRNA to PDCD4 significantly gave rise to tumors that were comparable to the untreated controls (Fig. 5A and 5C), confirming that the tumor growth is specifically regulated by PDCD4 and represents a crucial functional linkage between mir-21 and PDCD4 in vivo.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Negative regulation of Pdcd4 by mir-21 has recently been demonstrated in glioblastoma and in several other tumors.41 -44”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [41]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [42]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [43]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [44]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Pdcd4, a described target of mir-21, 16 -18 has been characterized as both a tumor suppressor 16,21 -25 and a pro-apoptotic gene that may function by binding eukaryotic initiation factor 4A (eIF4A) and inhibiting translation initiation.38 -40”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [38]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [39]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [40]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Elevated expression of miR-21 has been documented in several different types of cancer including those arising in breast, 9,16 brain, 11 -15 prostate, 29 ovaries, 30,31 colon, 32 and pancreas, 33 as well as cervical carcinoma, 34 hepatocellular carcinoma, 35 chronic lymphocytic leukemia, 36 and acute myeloid leukemia.37”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [9]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [16]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [14]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [15]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [29]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
In the paper
“Although an additional major pathway of Pdcd4 inactivation is the increased proteasomal degradation of Pdcd4 due to its phosphorylation by Akt and p70(S6K), 46 our findings provide strong evidence that, by inhibition of Pdcd4 by mir-21, over-expression contributes to glioblastoma growth.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [46]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“This is similar to the antiapoptotic activity of mir-21 in hepatocellular carcinoma where mir-21 has been shown to downregulate PTEN, initiate caspase activity, and lead to decreased apoptosis.35,45”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [35]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [45]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, our data suggest that, along with suppression of Pdcd4's pro-apoptotic function, downregulation of its tumor-suppressive activity also contributes to the oncogenic role of mir-21.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“The anti-apoptotic activity for mir-21 in glioblastoma lines that we observed is consistent with previously published data.11,12”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [11]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [12]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
In the paper
“For example, miR-21 has been shown to inhibit apoptosis by regulating Bcl-2 in murine breast cancer model 49,50 and to inhibit gemcitabine-induced apoptosis by modulating PTEN and the PI3K pathway.51”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [51]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Data are representative of 5 independent xenograft experiments (total n ¼ 24 animals per condition).”
- Also stated in: § Discussion · plain
“Data are averages of 5 independent xenograft experiments (total n ¼ 24 animals per condition) + SEM.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Strength:plain· not yet calibratedn = 24Tests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Also stated in: § Discussion · plain
In the paper
“Consistent with this idea is the observation that mir-21 regulation of 2 important matrix metalloproteinase inhibitors, RECK and TIMP3, may be of importance in vivo.13”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [13]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Our finding that high levels of Pdcd4 expression inhibited tumor growth suggests that inhibiting Pdcd4 degradation or enhancing its expression may be a therapeutic strategy of importance for glioblastoma.”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim. It may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“For example, miR-21 has been shown to inhibit apoptosis by regulating Bcl-2 in murine breast cancer model 49,50 and to inhibit gemcitabine-induced apoptosis by modulating PTEN and the PI3K pathway.51”
§ Downregulation of Pdcd4 by mir-21 facilitates glioblastoma proliferation in vivo > Discussion
What the sources say
- Not matchedcites [49]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites [50]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
The paper relies on this without support.
The effect of mir-21 regulation of Pdcd4 on specific biological activities (apoptosis, proliferation, anchorage-independent growth, or in vivo growth of glioblastoma xenografts) has not been studied.
“However, the effect of mir-21 regulation of Pdcd4 on specific biological activities of pathologic potential (eg, apoptosis, proliferation, anchorage-independent growth, or more significantly, in vivo growth of glioblastoma xenografts) has, to our knowledge, not been studied.”
The paper relies on this without support.
Anchorage-independent growth in soft agar correlates closely with tumorigenicity of transformed cells.
“Anchorage-independent growth assayed in soft agar is a characteristic of transformed cells that correlates closely with their tumorigenicity.”
The paper relies on this without support.
The effect of mir-21/Pdcd4 regulation on specific biological activities, such as apoptosis, proliferation, or anchorage-independent growth, has not been studied.
“Although mir-21 has been shown to regulate Pdcd4 in glioblastoma, 18 the effect of mir-21/Pdcd4 regulation on specific biological activities, such as apoptosis, proliferation, or anchorageindependent growth, has not been studied.”
The paper relies on this without support.
The effect on in vivo growth of glioblastoma cells of mir-21/Pdcd4 has not been explored.
“More significantly, the effect on in vivo growth of glioblastoma cells of mir-21/Pdcd4 has not been explored.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“miR-21 is a well-known miRNA, found to be overexpressed in almost all cancer types, where its upregulation promotes cell proliferation, invasion, and metastatic behavior.”
From Potential Therapeutic Effects of Exosomes Packed With a miR-21-Sponge Construct in a Rat Model of Glioblastoma (2019) · cites this paper as [18]
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“Our data on the effects of miR-21 enriched exosomes is in agreement with the previous reports demonstrating that overexpressed miR-21 in cell lines can increase the proliferation rate and malignant behavior of the cells (17–23).”
From Potential Therapeutic Effects of Exosomes Packed With a miR-21-Sponge Construct in a Rat Model of Glioblastoma (2019) · cites this paper as [18]
Experimental — accuracy not yet measuredThe cited source says what the claim attributes to it.
In the citing paper
“miR-21 targets several genes such as PDCD4, TIMP3, and RECK, which are key regulators of apoptotic and metastatic pathways (17–23).”
From Potential Therapeutic Effects of Exosomes Packed With a miR-21-Sponge Construct in a Rat Model of Glioblastoma (2019) · cites this paper as [18]
The cited source says what the claim attributes to it.
In the citing paper
“Previously, we showed that overexpression of PDCD4 leads to decreased anchorage-independent growth in glioblastoma (GBM)-derived cell lines and decreased tumor growth in a GBM xenograft model.”
From Tumor suppressor PDCD4 inhibits NF-κB-dependent transcription in human glioblastoma cells by direct interaction with p65 (2014) · cites this paper as [13]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Colony-count rescue is described in opposite directions
MinorThe results say that adding siRNA to Pdcd4 increases colony formation relative to anti-mir-21 alone. The discussion instead says the combined treatment produces 85% as many colonies as anti-mir-21 alone, which would be a decrease.
“Compared with cells that were treated with anti-mir-21 only, U251 or U87 that were treated with anti-mir-21 and siRNA to Pdcd4 produced higher number of colonies, similar to those formed by untreated U251 or U87 (Fig. 4A and B).”
“Interestingly, cells treated with anti-mir-21 and siRNA to Pdcd4 produced 85% of the colonies compared to cells treated with anti-mir-21 only.”
TUNEL results are assigned to the cell-cycle figure panel
MinorThe results cite Fig. 3B for TUNEL staining, but the figure caption identifies panel B as cell-cycle analysis; it identifies panel C as TUNEL staining.
“Also, TUNEL staining revealed enhanced apoptosis in U251 (Fig. 3B) and U87 cells (data not shown) treated with anti-mir-21, compared with cells cultured in either medium alone or with NS control.”
“(B) Cell-cycle analyses of U251 and U87 cells and cells transfected with non-specific negative/toxicity anti-mir (NS) control (30 mM) or anti-mir-21 (30 mM) as well as U251 Pdcd4 and U87 Pdcd4 cells.”
Figure 1B identifies different Western blot targets
MinorThe caption calls panel B a Western blot of mir-21, then says the blot quantifies Pdcd4 protein using an anti-Pdcd4 antibody.
“(B) Western blot analysis of mir-21 in primary tissues (2H, 4A10, 35A28, and 52A28) and GBM-derived cell lines (SNB19, U251, U87, and SF767), compared with normal human brain samples (NB4330 and NB4126).”
“Forty micrograms of protein from whole-cell lysates were loaded in each well for quantifying Pdcd4 protein levels by Western blot analysis using an anti-Pdcd4 antibody.”
Cited works that were retracted
Works this paper cites that were later retracted, from the retraction notices publishers deposit. Major when the notice came out before this paper was published.
Cites a retracted work: 10.1002/jcb.20982
InfoThe cited work was retracted on 2025-04-28 (notice 10.1002/jcb.70023), not before this paper was published (2011-06-01).
Cited work 10.1002/jcb.20982 · retracted 2025-04-28 · notice 10.1002/jcb.70023 · this paper published 2011-06-01
“Kutay, 2006, Journal of cellular biochemistry, 99, 671, 10.1002/jcb.20982”
Citations
Cites
1 retracted
RETRACTED: Downregulation of miR‐122 in the rodent and human hepatocellular carcinomas
Kutay, H., Bai, S., Datta, J., Motiwala, T., Pogribny, I., Frankel, W., Jacob, S. T., & Ghoshal, K. (2006) · Journal of Cellular Biochemistry · doi:10.1002/jcb.20982 · Cited by 608
RetractedMicroRNA signatures in human cancers
Calin, G. A., & Croce, C. M. (2006) · Nature reviews. Cancer · doi:10.1038/nrc1997 · Cited by 7,668
Oncomirs—MicroRNAs with a role in cancer
Esquela-Kerscher, A., & Slack, F. J. (2006) · Nature Reviews Cancer · doi:10.1038/nrc1840 · Cited by 5,884
A microRNA expression signature of human solid tumors defines cancer gene targets
Volinia, S., Calin, G. A., Liu, C.-G., Ambs, S., Cimmino, A., Petrocca, F., Visone, R., Iorio, M., Roldo, C., Ferracin, M., et al. (2006) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0510565103 · Cited by 5,697
Real-time quantification of microRNAs by stem-loop RT-PCR
Chen, C. (2005) · Nucleic Acids Research · doi:10.1093/nar/gni178 · Cited by 4,989
MicroRNA-21 Regulates Expression of the PTEN Tumor Suppressor Gene in Human Hepatocellular Cancer
Meng, F., Henson, R., Wehbe–Janek, H., Ghoshal, K., Jacob, S. T., & Patel, T. (2007) · Gastroenterology · doi:10.1053/j.gastro.2007.05.022 · Cited by 2,773
MicroRNA-21 Is an Antiapoptotic Factor in Human Glioblastoma Cells
Chan, J. A., Krichevsky, A. M., & Kosik, K. S. (2005) · Cancer Research · doi:10.1158/0008-5472.can-05-0137 · Cited by 2,557
Asangani, I. A., Rasheed, S. A. K., Nikolova, D. A., Leupold, J. H., Colburn, N. H., Post, S., & Allgayer, H. (2008) · Oncogene · doi:10.1038/sj.onc.1210856 · Cited by 1,882
Self-citationSi, M.-L., Zhu, S., Wu, H., Lu, Z., Wu, F., & Mo, Y.-Y. (2007) · Oncogene · doi:10.1038/sj.onc.1210083 · Cited by 1,600
MicroRNA Signatures in Human Ovarian Cancer
Iorio, M. V., Visone, R., Leva, G. D., Donati, V. L., Petrocca, F., Casalini, P., Taccioli, C., Volinia, S., Liu, C.-G., Alder, H., et al. (2007) · Cancer Research · doi:10.1158/0008-5472.can-07-1936 · Cited by 1,396
Flagged first, then by citations
2 of the 55 references couldn’t be matched to a known paper.
Research works printed but not linked: 3
- Gao, 2007, Oncology reports, 17, 123
- 2007, 133, 647
- 2008, Cell research, 18, 350, 10.1038/cr.2008.24 · DOI · Paper page
Cited by
Sorted by citations
Teplyuk, N. M., Mollenhauer, B., Gabriely, G., Giese, A., Kim, E. L., Smolsky, M., Kim, R. Y., Saria, M. G., Pastorino, S., Kesari, S. P., et al. (2012) · Neuro-Oncology · doi:10.1093/neuonc/nos074 · Cited by 304
Møller, H. G., Rasmussen, A. P., Andersen, H. H., Johnsen, K. B., Henriksen, M., & Duroux, M. C. (2012) · Molecular Neurobiology · doi:10.1007/s12035-012-8349-7 · Cited by 273
“ANP32Ad, SMARCA4, Caspases, PTEN, Cdc25A, HNRPK, TAp63, Spry2d, LRRFIP1, PDCD4 1:Invasiveness↑ [21–28, 30, 31, 35–55] 2: Invasiveness↓, Apoptosis↑, Viability↓, Proliferation↓, In vivo tumor volume↓, Chemosensitivity↑ Hsa-mir-23a [22–25, 35, 37, 52] Hsa-mir-25c Mdm2, TSC1 1:In vivo tumor volume↓ [22–26, 30, 101] Hsa-mi…”
BackgroundResultInfluentialmiR-124 Inhibits STAT3 Signaling to Enhance T Cell–Mediated Immune Clearance of Glioma
Wei, J., Wang, F., Kong, L.-Y., Xu, S., Doucette, T. A., Ferguson, S. D., Yang, Y., McEnery, K., Jethwa, K. R., Gjyshi, O., et al. (2013) · Cancer Research · doi:10.1158/0008-5472.can-12-4318 · Cited by 253
“In addition, oncogenic miR inhibition in murine glioma models has resulted in in vivo growth inhibition (16).”
BackgroundMicroRNAs in glioblastoma multiforme pathogenesis and therapeutics
Shea, A. A., Harish, V., Afzal, Z., Chijioke, J., Kedir, H., Dusmatova, S., Roy, A., Ramalinga, M., Harris, B. T., Blancato, J. K., et al. (2016) · Cancer Medicine · doi:10.1002/cam4.775 · Cited by 211
“AP- 1 induces miR- 21, which downregulates tumor suppressors PDCD4 and PTEN.”
BackgroundInfluentialLi, B., Ren, S., Li, X., Wang, Y., Garfield, D. H., Zhou, S., Chen, X., Su, C., Chen, M., Kuang, P., et al. (2013) · Lung Cancer · doi:10.1016/j.lungcan.2013.11.003 · Cited by 179
Metadata
- Authors
- Gaur, A. B., Holbeck, S. L., Colburn, N. H., & Israel, M. A.
- Affiliations
- Dartmouth College (US)
- Corresponding author
- Gaur, A. B.
- Venue
- Neuro-Oncology
- Publisher
- Oxford University Press (OUP)
- Published
- 2011-06-01
- Volume
- 13
- Issue
- 6
- Pages
- 580-590
- ISSN
- 1522-8517 (ISSN-L)
- 1523-5866
- PMC
- PMC3107097
- OpenAlex
- W2097617161
- Semantic Scholar
- baf2769011f484edff3d111bdecfc52cb2d992b6
- Cited by
- 180
- References
- 55
- Citations by year
- 2026: 5 · 2025: 10 · 2024: 8 · 2023: 9 · 2022: 11 · 2021: 16 · 2020: 14 · 2019: 9 · 2018: 7 · 2017: 13 · 2016: 13 · 2015: 14 · 2014: 15 · 2013: 19 · 2012: 15
- FWCI
- 5.00
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Neuro-Oncology (publishedVersion)
- PubMed (publishedVersion)
- Europe PMC (PubMed Central) (submittedVersion)
- PubMed Central (submittedVersion)
- Funders
- U.S. Department of Health and Human Services
- National Institutes of Health
- National Cancer Institute
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › MicroRNA in disease regulation
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Cancer-related molecular mechanisms research
- Health Sciences › Medicine › Oncology › Glioma Diagnosis and Treatment
- Keywords
- miR-21, PDCD4, glioblastoma, microRNA, tumor suppressor, cell proliferation, apoptosis, colony formation, xenograft tumor growth, carcinogenesis, post-transcriptional regulation
- MeSH terms
- Animals, Brain, Brain Neoplasms, Cell Adhesion, Cell Movement, Female, Glioblastoma, Humans, Mice, Nude, RNA, Messenger, Blotting, Northern, Blotting, Western, RNA-Binding Proteins, Apoptosis, Reverse Transcriptase Polymerase Chain Reaction, MicroRNAs, Cell Proliferation, Apoptosis Regulatory Proteins, Mice
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-22, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-22 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
