CoChat
Sign Up
Cited by 166Cancer, Hypoxia, and MetabolismAmino Acid Enzymes and MetabolismCancer, Lipids, and Metabolism

The DOI matches its Crossref record; 60 of the 60 references it cites were found in a registry or an index.

Glutamine Deprivation Induces Abortive S-Phase Rescued by Deoxyribonucleotides in K-Ras Transformed Fibroblasts

Open access
Gaglio, Daniela, Soldati, Chiara, Vanoni, Marco, Alberghina, Lilia, Chiaradonna, Ferdinando·2009·PLoS ONE
DOI 10.1371/journal.pone.0004715PMC PMC2650790
Open this paper in CoChat — free accountOpen PDF

Abstract

BACKGROUND: Oncogene activation plays a role in metabolic reprogramming of cancer cells. We have previously shown that K-ras transformed fibroblasts have a stronger dependence on glycolysis and a reduced oxidative phosphorylation ability as compared to their normal counterparts. Another metabolic adaptation of cancer cells, that has long been established, is their propensity to exhibit increased glutamine consumption, although the effects induced by glutamine deprivation on cancer cells are still controversial. METHODOLOGY AND PRINCIPAL FINDINGS: Here, by using nutritional perturbations and molecular physiology, we show that reduction or complete depletion of glutamine availability in K-ras transformed fibroblasts causes a strong decrease of proliferation ability and a slower re-entry of synchronized cells into the cell cycle. The reduced proliferation is accompanied by sustained expression of cyclin D and E, abortive S phase entrance and is dependent on Ras signalling deregulation, since it is rescued by expression of a dominant negative guanine nucleotide exchange factor. The growth potential of transformed cells as well as the ability to execute the G(1) to S transition is restored by adding the four deoxyribonucleotides, indicating that the arrest of proliferation of K-ras transformed cells induced by glutamine depletion is largely due to a reduced supply of DNA in the presence of signalling pathways promoting G(1) to S transition. CONCLUSIONS AND SIGNIFICANCE: Our results suggest that the differential effects of glutamine and glucose on cell viability are not a property of the transformed phenotype per se, but rather depend on the specific pathway being activated in transformation. For instance, myc-overexpressing cells have been reported to die under glutamine depletion and not under glucose shortage, while the opposite holds for ras-transformed fibroblasts as shown in this paper. These different responses of transformed cells to nutritional stress should be taken into account when designing anti-cancer therapies that aim to exploit metabolic differences between normal and transformed cells.

Overview

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1371/journal.pone.0004715

Cites

60 of 60 references verified0 citation errors · 0 not checkable

Statistics

Figures

Figure 1 Glutamine shortage induces cell proliferation arrest and S-phase accumulation in oncogenic K-ras transformed fibroblasts. Normal (⧫) and transformed (▪) cell lines were plated at 3000 cells/cm2 in 6-well plates in normal medium. Culture medium was replaced after 24 hours with a normal medium −4 mM glutamine- (A), an intermediate medium −1 mM glutamine- (B) and a low medium −0.5 mM glutamine- (C) and the cells were collected and counted at indicate time. (D) Morphological analysis of normal cells (upper images) and transformed cells (lower images) cultured in 4 mM glutamine (left images) and 0.5 mM glutamine (right images) at 96 hours. Cells were observed at phase-contrast microscopy. Exponentially growing normal and transformed cells were incubated for increasing periods of time (24, 48, 72, 96 and 144 h) in medium containing 4 mM and 0.5 mM glutamine, then harvested, counted and subjected to FACS analysis after staining with propidium iodide (E), or pulsed 30 minutes with BrdU and then analyzed by fluorescence microscopy using an anti-BrdU specific antibody (F). Results are the mean of at least triplicate determinations with standard deviations indicated. For BrdU staining were analyzed at least 200 cells for each sample.
Figure 1 Glutamine shortage induces cell proliferation arrest and S-phase accumulation in oncogenic K-ras transformed fibroblasts. Normal (⧫) and transformed (▪) cell lines were plated at 3000 cells/cm2 in 6-well plates in normal medium. Culture medium was replaced after 24 hours with a normal medium −4 mM glutamine- (A), an intermediate medium −1 mM glutamine- (B) and a low medium −0.5 mM glutamine- (C) and the cells were collected and counted at indicate time. (D) Morphological analysis of normal cells (upper images) and transformed cells (lower images) cultured in 4 mM glutamine (left images) and 0.5 mM glutamine (right images) at 96 hours. Cells were observed at phase-contrast microscopy. Exponentially growing normal and transformed cells were incubated for increasing periods of time (24, 48, 72, 96 and 144 h) in medium containing 4 mM and 0.5 mM glutamine, then harvested, counted and subjected to FACS analysis after staining with propidium iodide (E), or pulsed 30 minutes with BrdU and then analyzed by fluorescence microscopy using an anti-BrdU specific antibody (F). Results are the mean of at least triplicate determinations with standard deviations indicated. For BrdU staining were analyzed at least 200 cells for each sample.CC BY · PubMed Central
Figure 2 Expression of proteins involved in the G1 to S transition in normal and transformed cells. For the protein expression analysis normal cells (A) and transformed cells (C) grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine were collected at appropriate time points and 40 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with appropriate antibodies. One of at least three independent experiments is shown. (B1–B4 and D1–D4) Relative quantitative analysis of protein levels after Western blot film acquisition by scanner and densitometry analysis using Image J program. The densitometry values obtained for each protein were normalized by using the values of the corresponding vinculin and were plotted considering the densitometry value obtained for the sample 24 hours/4 mM glutamine as equal 1. Results are the mean of at least triplicate determinations with SD indicated.
Figure 2 Expression of proteins involved in the G1 to S transition in normal and transformed cells. For the protein expression analysis normal cells (A) and transformed cells (C) grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine were collected at appropriate time points and 40 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with appropriate antibodies. One of at least three independent experiments is shown. (B1–B4 and D1–D4) Relative quantitative analysis of protein levels after Western blot film acquisition by scanner and densitometry analysis using Image J program. The densitometry values obtained for each protein were normalized by using the values of the corresponding vinculin and were plotted considering the densitometry value obtained for the sample 24 hours/4 mM glutamine as equal 1. Results are the mean of at least triplicate determinations with SD indicated.CC BY · PubMed Central
Figure 3 Expression and localization of p27kip1 in normal and transformed cells. For p27kip1 expression analysis normal cells (A) and transformed cells (B) grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine were collected at appropriate time points and 40 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with p27kip1 specific antibody. One of at least three independent experiments is shown. Relative quantitative analysis of p27kip1 protein levels after Western blot film acquisition by scanner and densitometry analysis using Image J program, as described in Figure 2, in normal cells (C) and transformed cells (D). p27kip1 cellular localization in normal (E, F, G and H), and transformed (I, L M and N) cell lines was analyzed by immunofluorescence staining for p27kip1 (red staining), after 24 and 96 hours of growth in media supplemented with either 4 mM glutamine (left pictures) or 0.5 mM glutamine (right pictures). Nuclei were visualized by DAPI staining (Blue staining). The pictures are the result of a merge between the two single images acquired. At least 200 cells were scored for each sample. The averages of three independent experiments are presented in G, H, M and N with errors bars indicating SD. Bars, 20 µm.
Figure 3 Expression and localization of p27kip1 in normal and transformed cells. For p27kip1 expression analysis normal cells (A) and transformed cells (B) grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine were collected at appropriate time points and 40 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with p27kip1 specific antibody. One of at least three independent experiments is shown. Relative quantitative analysis of p27kip1 protein levels after Western blot film acquisition by scanner and densitometry analysis using Image J program, as described in Figure 2, in normal cells (C) and transformed cells (D). p27kip1 cellular localization in normal (E, F, G and H), and transformed (I, L M and N) cell lines was analyzed by immunofluorescence staining for p27kip1 (red staining), after 24 and 96 hours of growth in media supplemented with either 4 mM glutamine (left pictures) or 0.5 mM glutamine (right pictures). Nuclei were visualized by DAPI staining (Blue staining). The pictures are the result of a merge between the two single images acquired. At least 200 cells were scored for each sample. The averages of three independent experiments are presented in G, H, M and N with errors bars indicating SD. Bars, 20 µm.CC BY · PubMed Central
Figure 4 The GEF-DN protein completely reverts the phenotype induced by oncogenic K-ras expression in glutamine shortage. Cell cycle distribution (A), S-phase cell population (B), time-course of the expression of proteins involved in the G1 to S transition and pRb phosphorylation in Serine795 (C), relative quantitative analysis for p27kip1 protein (D) and p27kip1 cellular localization (E, F, G and H) in reverted cells grown in diverse initial glutamine availability as differently indicate in the Figure. The experiments were performed as indicated in previous figures. The averages of at least three independent experiments are presented in A, B, D, G and H with errors bars indicating SD. Bars, 20 µm.
Figure 4 The GEF-DN protein completely reverts the phenotype induced by oncogenic K-ras expression in glutamine shortage. Cell cycle distribution (A), S-phase cell population (B), time-course of the expression of proteins involved in the G1 to S transition and pRb phosphorylation in Serine795 (C), relative quantitative analysis for p27kip1 protein (D) and p27kip1 cellular localization (E, F, G and H) in reverted cells grown in diverse initial glutamine availability as differently indicate in the Figure. The experiments were performed as indicated in previous figures. The averages of at least three independent experiments are presented in A, B, D, G and H with errors bars indicating SD. Bars, 20 µm.CC BY · PubMed Central
Figure 5 Analysis of some glutamine-dependent cellular processes in normal and transformed cells. Amount of the total RNA, proteins and ratio RNA/protein for single cell calculated after spectrophotometric determination of total RNA extracted by using TRIzol solution and different lysis buffer (protein) of normal and transformed cells grown in 4 mM glutamine (A, C and E), and 0.5 mM glutamine (B, D and F) along a time course. Normal (G) and transformed (H) cell lines were plated at 3000 cells/cm2 in 6-well plates in normal medium. Culture medium was replaced after 24 hours with a normal medium −4 mM glutamine- (◊), a low medium −0.5 mM glutamine- (□), a medium with 0.5 mM glutamine and 2 mM pyruvate (▵) and a medium with 0.5 mM glutamine and 2 mM malate (○) and then the cells were collected and counted at indicate time. ATP content in the two cell lines was measured using a luciferin-luciferase assay along the time course in 4 mM (I), 1 mM (L) and 0.5 mM glutamine availability (M). ATP concentrations were calibrated against ATP standards and expressed as nanomoles per 10.000 cells. In all the experiments the averages of at least three independent experiments are presented with errors bars indicating SD.
Figure 5 Analysis of some glutamine-dependent cellular processes in normal and transformed cells. Amount of the total RNA, proteins and ratio RNA/protein for single cell calculated after spectrophotometric determination of total RNA extracted by using TRIzol solution and different lysis buffer (protein) of normal and transformed cells grown in 4 mM glutamine (A, C and E), and 0.5 mM glutamine (B, D and F) along a time course. Normal (G) and transformed (H) cell lines were plated at 3000 cells/cm2 in 6-well plates in normal medium. Culture medium was replaced after 24 hours with a normal medium −4 mM glutamine- (◊), a low medium −0.5 mM glutamine- (□), a medium with 0.5 mM glutamine and 2 mM pyruvate (▵) and a medium with 0.5 mM glutamine and 2 mM malate (○) and then the cells were collected and counted at indicate time. ATP content in the two cell lines was measured using a luciferin-luciferase assay along the time course in 4 mM (I), 1 mM (L) and 0.5 mM glutamine availability (M). ATP concentrations were calibrated against ATP standards and expressed as nanomoles per 10.000 cells. In all the experiments the averages of at least three independent experiments are presented with errors bars indicating SD.CC BY · PubMed Central
Figure 6 Proliferation analysis of normal and transformed cells adding in culture medium the four dNTPs. Normal (A) and transformed (B) cell lines were plated as previously described. Culture medium was replaced after 24 hours (indicated as 0 h) with a normal medium −4 mM glutamine- (◊), a low medium −0.5 mM glutamine- (□), a medium with 0.5 mM glutamine and 10 µM dNTPs -ATP, GTP, TTP and CTP- (▵) and a medium with 0.5 mM glutamine and 10 µM dNTPs in which the dNTPs were added at 0 and 48 hours (○), then the cells were collected and counted at indicate time. Normal (left panels) and transformed (right panels) cells, synchronized by 24 hours serum starvation, were released in a medium containing 10% serum, 4 mM or 0.5 mM glutamine, dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. Representative cytograms, obtained for asynchronous and 0 hours (time 0) time point samples respectively, plotting BrdU content (labeled cells) vs. PI staining (DNA content) (Figure 6 C - normal cells - and D - transformed cells -). Red color in the plot represents the S-phase cells. The percentages of cells in G1 (panels E and F), S (panels G and H) and G2/M (panels I and L), phase of normal (left panels) and transformed (right panels) cells released in 4 mM and 0.5 mM glutamine alone or plus dNTPs obtained by bi-parametric analysis as shown above, are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.
Figure 6 Proliferation analysis of normal and transformed cells adding in culture medium the four dNTPs. Normal (A) and transformed (B) cell lines were plated as previously described. Culture medium was replaced after 24 hours (indicated as 0 h) with a normal medium −4 mM glutamine- (◊), a low medium −0.5 mM glutamine- (□), a medium with 0.5 mM glutamine and 10 µM dNTPs -ATP, GTP, TTP and CTP- (▵) and a medium with 0.5 mM glutamine and 10 µM dNTPs in which the dNTPs were added at 0 and 48 hours (○), then the cells were collected and counted at indicate time. Normal (left panels) and transformed (right panels) cells, synchronized by 24 hours serum starvation, were released in a medium containing 10% serum, 4 mM or 0.5 mM glutamine, dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. Representative cytograms, obtained for asynchronous and 0 hours (time 0) time point samples respectively, plotting BrdU content (labeled cells) vs. PI staining (DNA content) (Figure 6 C - normal cells - and D - transformed cells -). Red color in the plot represents the S-phase cells. The percentages of cells in G1 (panels E and F), S (panels G and H) and G2/M (panels I and L), phase of normal (left panels) and transformed (right panels) cells released in 4 mM and 0.5 mM glutamine alone or plus dNTPs obtained by bi-parametric analysis as shown above, are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.CC BY · PubMed Central
Figure 7 Cell cycle of synchronized normal and transformed cells released in 0 mM glutamine±dNTPs. Normal and transformed cells, synchronized by 24 hours of serum starvation, were released in a medium containing 10% serum, 4 mM or 0 mM glutamine, dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. The percentages of cells in G1 (panels A and B), S (panels C and D) and G2/M (panels E and F) phase of normal (left panels) and transformed (right panels) cells released in 4 mM and 0 mM glutamine alone or plus dNTPs obtained by bi-parametric analysis are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.
Figure 7 Cell cycle of synchronized normal and transformed cells released in 0 mM glutamine±dNTPs. Normal and transformed cells, synchronized by 24 hours of serum starvation, were released in a medium containing 10% serum, 4 mM or 0 mM glutamine, dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. The percentages of cells in G1 (panels A and B), S (panels C and D) and G2/M (panels E and F) phase of normal (left panels) and transformed (right panels) cells released in 4 mM and 0 mM glutamine alone or plus dNTPs obtained by bi-parametric analysis are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.CC BY · PubMed Central
Figure 8 Activation of AKT, AMPK and TOR pathways in normal and transformed cells. (A) Time course expression and phosphorylation of the AKT protein in normal and transformed cell lines growing in media supplemented with different initial glutamine concentrations. For the protein expression analysis normal cells and transformed cells grown in media containing 4 mM glutamine and 0.5 mM glutamine, were collected at appropriate time points and 50 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with a specific anti-phosphorylatedSer473 AKT (p-AKT) antibody and an anti-AKT (AKT) antibody. (B) Time course expression and phosphorylation of the AMPKα protein in normal and transformed cell lines growing in media supplemented with different initial glutamine concentrations. For the protein expression analysis normal cells and transformed cells grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine, were collected at appropriate time points and 50 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with a specific anti-phosphorylatedThr172 AMPK (p-AMPK) antibody and an anti-AMPK (AMPK) antibody. (C) Time course expression and phosphorylation of the S6K protein in normal and transformed cell lines grown as described in B. Western blotting analysis has been performed by using a specific anti-phosphorylatedThr389 S6K (p-AKT) antibody and an anti-S6K (S6K) antibody. The panels are representative of a triplicate analysis (Akt and AMPK) or duplicate analysis (S6K).
Figure 8 Activation of AKT, AMPK and TOR pathways in normal and transformed cells. (A) Time course expression and phosphorylation of the AKT protein in normal and transformed cell lines growing in media supplemented with different initial glutamine concentrations. For the protein expression analysis normal cells and transformed cells grown in media containing 4 mM glutamine and 0.5 mM glutamine, were collected at appropriate time points and 50 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with a specific anti-phosphorylatedSer473 AKT (p-AKT) antibody and an anti-AKT (AKT) antibody. (B) Time course expression and phosphorylation of the AMPKα protein in normal and transformed cell lines growing in media supplemented with different initial glutamine concentrations. For the protein expression analysis normal cells and transformed cells grown in media containing 4 mM glutamine, 1 mM glutamine and 0.5 mM glutamine, were collected at appropriate time points and 50 µg of proteins from the total cellular extract were subjected to SDS-PAGE followed by Western blotting with a specific anti-phosphorylatedThr172 AMPK (p-AMPK) antibody and an anti-AMPK (AMPK) antibody. (C) Time course expression and phosphorylation of the S6K protein in normal and transformed cell lines grown as described in B. Western blotting analysis has been performed by using a specific anti-phosphorylatedThr389 S6K (p-AKT) antibody and an anti-S6K (S6K) antibody. The panels are representative of a triplicate analysis (Akt and AMPK) or duplicate analysis (S6K).CC BY · PubMed Central
Figure 9 Analysis of cell cycle upon rapamycin treatment. Normal and transformed cells, synchronized by 24 hours of serum starvation, were released in a medium containing 10% serum, 4 mM glutamine±Rapamycin or 0 mM glutamine±Rapamycin and±dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. The percentages of cells in G1 (panels A and B), S (panels C and D) and G2/M (panels E and F) phase of normal (left panels) and transformed (right panels) cells, released in the mediums indicated above, and obtained by bi-parametric analysis are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.
Figure 9 Analysis of cell cycle upon rapamycin treatment. Normal and transformed cells, synchronized by 24 hours of serum starvation, were released in a medium containing 10% serum, 4 mM glutamine±Rapamycin or 0 mM glutamine±Rapamycin and±dNTPs and BrdU for continuous DNA labeling. At indicate time points the cells were collected and stained with propidium iodide and anti-BrdU specific antibody and analyzed by flow cytometry. The percentages of cells in G1 (panels A and B), S (panels C and D) and G2/M (panels E and F) phase of normal (left panels) and transformed (right panels) cells, released in the mediums indicated above, and obtained by bi-parametric analysis are represented. The asterisks indicate the S or G2/M phase peaks identified in both glutamine availability. The error bars correspond to standard deviations of triplicate analysis.CC BY · PubMed Central
Figure 10 A model of the role of glutamine in controlling the G1/S transition. In the panels the following convention are used. Metabolic connections are indicated by black arrows. Blue lines indicate positive (arrowhead) or negative (blunt end) regulatory connections. Up- and down-regulation are indicated by red arrows pointing either upwards or downwards, respectively. A full block is indicated by a red X, a leaky block by a dotted X. (A) Some metabolic roles of glutamine are represented within a light blue area. (B) Summary of events originating from glutamine shortage in asynchronous and synchronous normal cells. Biological readouts of proteins involved in the G1 to S transition and the effects on cell cycle are reported. (C) Summary of events originating from glutamine shortage in asynchronous and synchronous K-ras transformed cells. Biological readouts of proteins involved in the G1 to S transition and the effects on cell cycle are reported.
Figure 10 A model of the role of glutamine in controlling the G1/S transition. In the panels the following convention are used. Metabolic connections are indicated by black arrows. Blue lines indicate positive (arrowhead) or negative (blunt end) regulatory connections. Up- and down-regulation are indicated by red arrows pointing either upwards or downwards, respectively. A full block is indicated by a red X, a leaky block by a dotted X. (A) Some metabolic roles of glutamine are represented within a light blue area. (B) Summary of events originating from glutamine shortage in asynchronous and synchronous normal cells. Biological readouts of proteins involved in the G1 to S transition and the effects on cell cycle are reported. (C) Summary of events originating from glutamine shortage in asynchronous and synchronous K-ras transformed cells. Biological readouts of proteins involved in the G1 to S transition and the effects on cell cycle are reported.CC BY · PubMed Central

Verification

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

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?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Citations

Cites

Cited by

Sorted by citations

See all 166

Related

See all

Metadata

Authors
Gaglio, D., Soldati, C., Vanoni, M., Alberghina, L., & Chiaradonna, F.
Affiliations
University of Milano-Bicocca (IT)
Corresponding author
Chiaradonna, Ferdinando
ORCID
Venue
PLoS ONE
Publisher
Public Library of Science (PLoS)
Published
2009-03-05
Volume
4
Issue
3
Pages
e4715
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0004715
PMC
PMC2650790
OpenAlex
W2070710923
Cited by
164
References
60
Citations by year
2026: 2 · 2025: 5 · 2024: 12 · 2023: 9 · 2022: 21 · 2021: 11 · 2020: 10 · 2019: 16 · 2018: 6 · 2017: 12 · 2016: 9 · 2015: 12 · 2014: 14 · 2013: 8 · 2012: 6
FWCI
1.90
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • BOA (University of Milano-Bicocca) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
Funders
  • Fund for Astrophysical Research
  • Regione Lombardia
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Cancer, Hypoxia, and Metabolism
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Biochemistry › Amino Acid Enzymes and Metabolism
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Cancer, Lipids, and Metabolism
Keywords
glutamine deprivation, deoxyribonucleotides, G1/S transition, Ras signaling, guanine nucleotide exchange factor, cell cycle arrest, cancer metabolism, metabolic reprogramming, nutritional stress, cell proliferation
MeSH terms
Animals, Cell Cycle, Cell Transformation, Neoplastic, Deoxyribonucleotides, Fibroblasts, Glutamine, Genes, ras, S Phase, 3T3 Cells, Cell Proliferation, 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.

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