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Cited by 200CRISPR and Genetic EngineeringVirus-based gene therapy researchCAR-T cell therapy research

CRISPR-Cas9: a new and promising player in gene therapy

Open access
Xiao-Jie, Lu, Hui-Ying, Xue, Zun-Ping, Ke, Jin-Lian, Chen, Li-Juan, Ji·2015·Journal of Medical Genetics
DOI 10.1136/jmedgenet-2014-102968
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Abstract

First introduced into mammalian organisms in 2013, the RNA-guided genome editing tool CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9) offers several advantages over conventional ones, such as simple-to-design, easy-to-use and multiplexing (capable of editing multiple genes simultaneously). Consequently, it has become a cost-effective and convenient tool for various genome editing purposes including gene therapy studies. In cell lines or animal models, CRISPR-Cas9 can be applied for therapeutic purposes in several ways. It can correct the causal mutations in monogenic disorders and thus rescue the disease phenotypes, which currently represents the most translatable field in CRISPR-Cas9-mediated gene therapy. CRISPR-Cas9 can also engineer pathogen genome such as HIV for therapeutic purposes, or induce protective or therapeutic mutations in host tissues. Moreover, CRISPR-Cas9 has shown potentials in cancer gene therapy such as deactivating oncogenic virus and inducing oncosuppressor expressions. Herein, we review the research on CRISPR-mediated gene therapy, discuss its advantages, limitations and possible solutions, and propose directions for future research, with an emphasis on the opportunities and challenges of CRISPR-Cas9 in cancer gene therapy.

AI snapshot

Written from the paper’s full text.

TL;DR

This review argues that CRISPR-Cas9, first introduced into mammalian cells in 2013, is a simple, multiplexable genome-editing tool with therapeutic potential in infectious diseases, monogenic disorders, and cancer. It concludes that clinical translation still requires reliable off-target profiling, higher editing efficiency, and improved HDR rates.

Key findings

  • CRISPR-Cas9 offers advantages over ZFN/TALEN and RNAi, including simple sgRNA redesign, multiplexing, and ability to induce gain- and loss-of-function mutations; it has been used to correct monogenic disease mutations, engineer pathogen genomes, induce protective mutations, and target cancer-associated viruses or oncogenic pathways.
  • In a mouse cataract model caused by a *Crygc* mutation, CRISPR-Cas9 germline editing produced 10 modified offspring out of 22 live offspring (45.45% editing efficiency): all 4 HDR-edited mice were cataract-free, while of 6 NHEJ-edited mice, 2 were cataract-free and 4 remained cataractous.
  • In adult mice with hereditary tyrosinemia, hydrodynamic tail-vein delivery of CRISPR-Cas9 plus a homologous donor corrected 0.25% of liver cells initially and 33.5% at 33 days postinjection, sufficient to rescue the disease phenotype.
  • In cancer models, CRISPR-Cas9 targeting HPV16 E6/E7 in SiHa cervical carcinoma cells inhibited proliferation in vitro and in xenografts; in EBV-positive Burkitt’s lymphoma cells it inhibited proliferation and reduced viral load; an AND-gate system achieved bladder-cancer-specific expression of p21, E-cadherin, or Bax.

Methods

  • Narrative review of CRISPR-Cas9 mechanisms, merits, and gene therapy applications, with emphasis on cancer gene therapy.
  • Synthesizes published studies in cell lines and animal models, including mouse models of Duchenne muscular dystrophy, cataract, hereditary tyrosinemia, and cancer, as well as human stem cell/iPSC studies.
  • No systematic search strategy, meta-analysis, or new experimental data are reported; the paper is a qualitative literature synthesis.

Limitations

  • The paper states that off-target effects must be accurately profiled and controlled; current silicon prediction and in vitro selection identify only part of off-target cleavage, and Cas9 binding can be uncoupled from cleavage, requiring more unbiased genome-wide methods.
  • The paper states that editing efficiency and HDR rate remain major challenges; cancer gene therapy requires high edit efficiency beyond current CRISPR-Cas9 technology, and delivery is limited by factors such as AAV cargo capacity.
  • Evident from the text: as a narrative review, it lacks a systematic search or quantitative synthesis and does not provide new experimental validation; germline modification is noted as currently not applicable to humans.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1136/jmedgenet-2014-102968

Cites

70 of 70 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 81 cited sources checked · 0 supported · 0 flagged

  • Findingcitation

    Liu et al used CRISPR-Cas9-mediated bladder cancer cell-specific genome editing using an AND logic gate.

    “An example of therapeutic genome manipulations comes from study by Liu et al 47 in which CRISPR-Cas9-mediated bladder cancer cell-specific genome editing using an AND logic gate (figure 2).”
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  • Findingcitation

    In a mouse model of DMD, CRISPR-Cas9-mediated germline editing gave rise to genetically mosaic offspring with 2-100% somatic cells carrying the corrected culprit gene.

    “In a mouse model of Duchenne muscular dystrophy (DMD), an inherited X-linked monogenic disease, CRISPR-Cas9-mediated gene editing in the germline gave rise to genetically mosaic offsprings with 2-100% somatic cells carrying the corrected version of the culprit gene.29”
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  • Findingcitation

    Seeger and Sohn showed that in HepG2 cells expressing HBV, introduction of a cccDNA-targeting CRISPR-Cas9 system resulted in decreased hepatitis B core antigen expression and mutated cccDNAs.

    “Recently, a study by Seeger and Sohn 28 showed that in HepG2 cells expressing HBV, the introduction of cccDNA-targeting CRISPR-Cas9 system resulted in both decreased hepatitis B core antigen expression and mutated cccDNAs”
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  • Findingcitation

    The dCas9-effector strategy has been applied in a genome-wide screening study in which gain-of-function mutations in melanoma cells that confer drug resistance were identified.

    “This dCas9-effector strategy has already been applied in genome wide screening study in which gain-of-function mutations in melanoma cells that confer drug resistance were identified.46”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [46] Konermann, 2015, Genome-scale transcriptional activation by an engineered CRISPR-Cas9 complex, Nature source

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  • Findingcitation

    Of 22 live offspring, 10 underwent culprit gene modifications (45.45%) either by HDR (n=4) or by NHEJ (n=6).

    “Of the 22 live offsprings, 10 underwent culprit gene modifications (the editing efficiency is 45.45%) either by HDR (n=4) (figure 1C left) or by NHEJ (n=6) (figure 1C right).”
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  • May combine two claims. 32
  • Classified as probably not a substantial claim. 8

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    Findingcitation

    In a Burkitt's lymphoma cell line with latent EBV infection, CRISPR-Cas9 treatment inhibited cell proliferation and reduced viral load.

    “Similarly, in a Burkitt's lymphoma cell line with latent EBV infection, CRISPR-Cas9 treatment inhibited cell proliferation and reduced viral load.42”
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    Findingcitation

    A recent clinical trial showed autologous reintroduction of CD4 T cells whose CCR5 gene was inactivated in vitro by ZFN was safe and led to decreased viral load.

    “Interestingly, a recent clinical trial 38 showed that autologous reintroduction of CD4T cells whose CCR5 gene was inactivated in vitro by ZFN was safe and lead to decreased viral load”
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    Findingcitation

    Yin et al delivered CRISPR-Cas9 and a donor template into adult mice with hereditary tyrosinemia via tail-vein hydrodynamic injection, resulting in gene corrections in 0.25% of liver cells initially and 33.5% at 33 days, sufficient to rescue the disease phenotype.

    “Yin et al, 32 for example, delivered CRISPR-Cas9 agents and a homologous donor template (in order to increase HDR rate) into adult mice with hereditary tyrosinemia via tail-vein hydrodynamic injection, resulting in gene corrections in 0.25% of liver cells initially, and in 33.5% of liver cells 33 days postinjection ( possibly due to selective advantages imposed by the correction), which was suffic”
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    Findingcitation

    In human intestinal stem cells from cystic fibrosis patients, CFTR was rectified by homologous recombination during CRISPR-Cas9 genome editing while pluripotency was retained.

    “In human intestinal stem cells collected from patients with cystic fibrosis, the culprit gene cystic fibrosis transmembrane conductance regulator was rectified by homologous recombination during CRISPR-Cas9 genome editing while the pluripotency was retained as demonstrated by formations of organ-like expansions in cell culture.33”
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    Findingcitation

    In mice liver, CRISPR-Cas9 induced loss-of-function mutation at the PCSK9 gene locus, leading to elevated hepatic LDL receptor level and dropped plasma cholesterol level.

    “In mice liver, CRISPR-Cas9 was reported to successfully induce loss-of-function mutation at PCSK9 gene locus, leading to elevated hepatic LDL receptor level and dropped plasma cholesterol level”
    Quote in the paperSubstantial claim0 of 1 sources checked
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    Findingcitation

    Of six offspring undergoing NHEJ, two were free of cataract due to coincidental frameshift restoration, while four remained cataract phenotype.

    “Interestingly, however, of the six offsprings undergoing NHEJ, two were also free of cataract thanks to coincidental frameshift restoration resulting from NHEJ-induced indel mutations, while the rest four remained cataract phenotype.30”
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    Findingreasoning

    In bladder cancer cells, Cas9 and sgRNAs were both expressed, mutating the LacI gene and abrogating its suppression on the effector gene, leading to bladder cancer cell-specific expression of the effector.

    “In bladder cancer cells, Cas9 and sgRNAs were both expressed, mutating LacI gene and abrogating its suppression on the effector gene, leading to bladder cancer cell-specific expression of the effector (figure 2C, right).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [47] source

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    Findingcitation

    Ebina et al reported that CRISPR-Cas9 can mutate the HIV-1 LTR in vitro, resulting in removal of integrated proviral DNA from part of host cells and a significant drop in virus expression.

    “Ebina et al 26 reported that CRISPR-Cas9 can mutate long terminal repeat (LTR) sequence of HIV-1 in vitro, resulting in removal of the integrated proviral DNA from the part of the host cells and a significant drop in virus expression.”
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    Findingcitation

    With CRISPR-Cas9, gene corrections have been successfully conducted in iPSCs derived from β-thalassemia patients and DMD patients.

    “With CRISPR-Cas9, gene corrections have been successfully conducted in iPSCs derived from β-thalassemia patients 35 and DMD patients, 36”
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    • cites 35 36

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    Findingcitation

    Wu et al corrected Crygc in mouse spermatogonial stem cells with CRISPR-Cas9 and picked SSC lines carrying the corrected gene without undesired genome perturbations.

    “To gain 100% rescue efficiency, Wu et al 31 corrected the culprit gene Crygc in mouse spermatogonial stem cells (SSCs) with CRISPR-Cas9, and then picked out SSC lines that carried the corrected gene without undesired genome perturbations.”
    Quote in the paperSubstantial claim0 of 1 sources checked
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    Findingcitation

    In the Liu et al study, effector genes p21, E-cadherin and Bax led to cancer-specific growth inhibition, migration suppression and apoptosis, respectively.

    “In this study, the effector genes were p21, E-cadherin and Bax (BCL2-associated X), leading to cancer-specific growth inhibition, migration suppression and apoptosis, respectively.”
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    Premisecitation

    On presence of a PAM on the opposite strand, sgRNA directs Cas9 to the target site by base-pairing, resulting in site-specific DNA double-strand breaks repaired by HDR if homologous sequences are available or otherwise by NHEJ.

    “On the presence of a protospacer-adjacent motif (PAM) on the opposite strand, sgRNA directs Cas9 to the target site by base-pairing, resulting in Cas9-generated sitespecific DNA double-strand breaks (DSBs) that are subsequently repaired by homologous directed repair (HDR) if the homologous sequences are available or otherwise by non-homologous endjoining (NHEJ).13 14 15”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 13 14 15

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    Premisecitation

    TALEN can be re-engineered to target and cleave mutant mitochondrial DNA in patient-derived cells, whereas mitochondrial genome-targeting CRISPR-Cas9 remains to be explored.

    “And moreover, TALEN can be re-engineered to target and cleave mutant mitochondrial DNA in patient-derived cells, 21 whereas mitochondrial genometargeting CRISPR-Cas9 remains an area to be explored.”
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    • cites [21] source

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  • May combine two claims.

    Interpretationnone given

    CRISPR-Cas9 can correct causal mutations in monogenic disorders and rescue disease phenotypes.

    “It can correct the causal mutations in monogenic disorders and thus rescue the disease phenotypes”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 30 31 32 33 34 35 36

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    Interpretationcitation

    With CRISPR-Cas9, targeting a new site requires only design of a complementary sgRNA, which is simpler than de novo synthesis of a bulky guiding protein as in ZFN- or TALEN-based tools.

    “First, with CRISPR-Cas9, to target a new site requires only the design of a complementary sgRNA (the nuclease Cas9 remains the same in all cases), which is much simpler than the de novo synthesis of a bulky guiding protein as in ZFN-or TALEN-based tools.”
    Quote in the paperSubstantial claim0 of 1 sources checked
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    Interpretationcitation

    CRISPR-Cas9 offers several advantages over conventional genome editing tools, including simple design, ease of use, and multiplexing.

    “offers several advantages over conventional ones, such as simple-to-design, easy-to-use and multiplexing”
    Quote in the paperSubstantial claim0 of 1 sources checked
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    Premisecitation

    Cas9 can be reprogrammed into nickase by inactivating either RuvC or HNH, or into catalytically inactive dCas9 by inactivating both.

    “Additionally, Cas9 can be reprogrammed into nickase (nCas9) by inactivating either RuvC or HNH, 16 or into catalytically inactive Cas9 (termed dead Cas9, or dCas9) by inactivating both of them”
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    Premisecitation

    TALEN generally produce less off-target effects relative to CRISPR-Cas9, partially due to the heterodimeric construction of FokI nuclease in TALEN.

    “Second, TALEN are generally reported to produce less off-target effects in relative to CRISPR-Cas9, 19 20 partially by virtue of the heterodimeric construction of FokI nuclease in TALEN.”
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    Premisecitation

    The core components of CRISPR-Cas9 are a nuclease Cas9 comprising RuvC and HNH domains and a single guide RNA derived from crRNA and tracrRNA.

    “the core components of CRISPR-Cas9 are a nuclease Cas9 comprising two catalytic active domains RuvC and HNH, and a single guide RNA (sgRNA) that is derived from CRISPR RNA (crRNA) and transacting CRISPR RNA.15”
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    Premisecitation

    TALEN can target more genome sites than CRISPR-Cas9 because CRISPR targets are restricted by PAM and a guanine at the 5' end whereas TALEN only requires thymine at the 5' end.

    “First, the targets of CRISPR-Cas9 are restricted by the presence of PAM sequence and a guanine at the 5 0 end 11, whereas the only restriction of TALEN targets is the presence of thymine at the 5 0 end, 18 which means that TALEN can target more genome sites than CRISPR-Cas9.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites 11 18

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    Premisecitation

    HDR leads to precise gene correction or replacement whereas NHEJ is error prone and may induce small insert or delete mutations.

    “HDR leads to precise gene correction or replacement whereas NHEJ is error prone and may induce small insert or delete (indel) mutations”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites 13 14 15

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    Interpretationcitation

    dCas9 can be fused to epigenetic modifiers; under sgRNA guidance, dCas9 and the modifiers access target sites and exert epigenetic regulations, a process termed epigenome editing that is a potential tool for anticancer modalities.

    “Moreover, dCas9 can be harnessed as a site-specific DNA binding domain and fused to epigenetic modifiers.Under the guidance of sgRNAs, dCas9 and the modifiers get access to the target sites and exert epigenetic regulations, 16 45 46 a process termed epigenome editing, which is also a potential tool for anticancer modalities.”
    Quote in the paperSubstantial claim0 of 1 sources checked
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  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Monogenic disorders are more amenable to gene therapies than polygenic diseases such as cancer.

    “Compared with polygenic diseases such as cancer, monogenic disorders are more amenable to gene therapies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationreasoning

    CRISPR-Cas9 possesses inherent advantages in engineering and disabling pathogen genomes to treat infectious diseases because it is derived from the microbial adaptive immune defense system.

    “CRISPR-Cas9 is derived from microbial adaptive immune defense system, and thus possesses inherent advantages in engineering and disabling pathogen genomes to treat infectious diseases.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    CRISPR-Cas9 can correct genetic mutations as demonstrated in monogenic diseases and modulate epigenetic states.

    “CRISPR-Cas9 can correct genetic mutations as demonstrated in monogenic diseases, [30][31][32][33][34][35][36] and modulate epigenetic states.16 43-46”
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    • cites [30][31][32][33][34][35][36]

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    • cites 16 43-46

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    Interpretationreasoning

    CRISPR-Cas9 can induce both gain- and loss-of-function mutations and suffers from less off-target effects than RNAi because it derives from prokaryote and has less crosstalk with eukaryotic components.

    “CRISPR-Cas9 system, on the contrary, can induce both gain-and loss-of-function mutations, and suffers from less off-target effects for that CRISPR-Cas9 derives from prokaryote and hence has less crosstalk with eukaryotic components than RNAi pathway does.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: RNAi effects are temporary, non-specific and limited to knocking down transcribed genes.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Deinococcus radiodurans can repair its genome from hundreds of short DNA fragments resulting from exogenous damages.

    “Moreover, previous study showed that bacterium Deinococcus radiodurans can repair its genome form hundreds of short DNA fragments resulting from exogenous damages.”
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    • cites [65] source

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    Premisecitation

    Cell-penetrating peptide-mediated delivery of CRISPR-Cas9 into cells increases editing efficiency, but the optimal editing efficiency remains under 20% in vitro.

    “Though cell-penetrating peptidemediated delivery of CRISPR-Cas9 into cells was reported to increase editing efficiency, the optimal editing efficiency was still under 20% in vitro.59”
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  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    CRISPR-Cas9-based (epi)genome manipulation therapies in cancer are hampered by heterogeneity in oncogenic mutation profiles.

    “As stated above, CRISPR-Cas9 based (epi)genome manipulation therapies in cancer are hampered by heterogeneity in oncogenic mutation profiles and the requirement of pretty high editing efficiency.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Modification of host cells to enhance anticancer immune responses or increase resistance to chemo- and radiotoxicity is a current hot spot in cancer gene therapy.

    “Currently, another hot spot in cancer gene therapy is the modifications of the host cells to enhance anticancer immune responses, 68 or to increase resistance to chemo-and radiotoxicity. 3”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [68] source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    AAV vectors are commonly used gene delivery tools for gene therapy research and clinical trials because of their efficiency and safety.

    “Adeno-associated virus (AAV) vectors are commonly used gene delivery tools for gene therapy research and clinical trials because of their efficiency and safety. 1 57 58”
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    Premisecitation

    CRISPR-Cas9 has been applied in T cell modification and immune modulation.

    “Given that CRISPR-Cas9 has been applied in T cell modification 70 and immune modulation, 70 71”
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  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Because CRISPR-Cas9 causes permanent genome alterations, its off-target effects must be accurately profiled and controlled when applied in gene therapy.

    “Because CRISPR-Cas9 causes permanent genome alterations, its off-target effects must be accurately profiled and controlled when applied in gene therapy.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    The RNA-guided genome editing tool CRISPR-Cas9 offers several advantages over protein-guided counterparts and RNAi techniques.

    “In conclusion, the RNA-guided genome editing tool CRISPR-Cas9 offers several advantages over protein guided counterparts and RNAi techniques.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Among mice genetically edited by CRISPR-Cas9, all HDR-mediated editing corrected causative gene defects and rescued disease phenotype, while only a small part of NHEJ-mediated editing had the corrective effect.

    “As shown in the study by Wu et al 30 among mice genetically edited by CRISPR-Cas9, all HDR-mediated editing corrected the causative gene defects and rescued disease phenotype while only a small part of NHEJ-mediated editing had the corrective effect.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [30] source

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  • May combine two claims.

    Interpretationreasoning

    Before CRISPR-Cas9 is translatable to the clinic, several challenges must be overcome, including reliably profiling and controlling off-target effects, increasing editing efficiency, and improving HDR rate.

    “Before it is translatable to the clinic to benefit patients, several challenges must be overcome, such as ways to reliably profile and control the off-target effects, ways to increase editing efficiency and ways to improve HDR rate.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    Increasing HDR rate can improve the efficiency and reliability of CRISPR-Cas9-mediated gene therapy while decreasing genomic toxic effects.

    “Therefore, increasing HDR rate can improve the efficiency and reliability of CRISPR-Cas9-mediated gene therapy while decrease genomic toxic effects concurrently.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The DSBs produced by CRISPR-Cas9 are subsequently processed by NHEJ or HDR.
    • Rests on an assumption: In many cases, HDR results in desired gene modifications while NHEJ gives rise to undesired indels that cause uncontrollable gene disruptions.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Many oncolytic viruses have been tested in clinical trials, with one licensed in China.

    “Many oncolytic viruses have been tested in clinical trials, 66 with one of them licensed in China.67”
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    Premisecitation

    DNA binding and cleavage by Cas9 are in some cases uncoupled; Cas9 can bind but not cleave partially complementary sequences and exert epigenomic regulatory effects, which is unpredictable by silicon methods relying on base pairing.

    “And moreover, DNA binding and cleavage by Cas9 are in some cases uncoupled, that is, Cas9 can bind to but not cleave DNA sequences that are partially complementary to sgRNA 49 and exert epigenomic regulatory effects, 43 44 which is unpredictable by silicon methods relying on base pairing.”
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39 of 39

  • The paper relies on this without support.

    RNAi effects are temporary, non-specific and limited to knocking down transcribed genes.

    “However, the effects of RNAi are temporary, non-specific and limited to knocking down transcribed genes.”

  • The paper relies on this without support.

    Cancer is a polygenic and heterogeneous disease.

    “First, cancer is a polygenic and heterogeneous disease.”

  • The paper relies on this without support.

    Unedited malignant cells retain unreduced malignancy, possess selective advantages over corrected cells and proliferate quickly.

    “the unedited cells retain unreduced malignancy, possess selective advantages over the 'corrected' cells and proliferate quickly”

  • The paper relies on this without support.

    The commonly used Cas9 gene derived from Streptococcus pyogenes is too big to transduce with wild-type AAV due to its limited genetic cargo.

    “However, the commonly used Cas9 gene derived from Streptococcus pyogenes is too big to transduce with wildtype AAV due to its limited genetic cargo.”

  • The paper relies on this without support.

    The DSBs produced by CRISPR-Cas9 are subsequently processed by NHEJ or HDR.

    “The DSBs produced by CRISPR-Cas9 are subsequently processed by NHEJ or HDR.”

  • The paper relies on this without support.

    In many cases, HDR results in desired gene modifications while NHEJ gives rise to undesired indels that cause uncontrollable gene disruptions.

    “In many cases, HDR results in desired gene modifications while NHEJ gives rise to undesired indels that cause uncontrollable gene disruptions.”

  • The paper relies on this without support.

    Compared with monogenetic diseases, studies on CRISPR-mediated gene therapy in polygenic and polyetiologic diseases lag behind.

    “with monogenetic diseases, studies on CRISPR-mediated gene therapy in polygenic and polyetiologic diseases lag behind.”

  • The paper relies on this without support.

    Some viruses can be genetically engineered to specifically infect and replicate in cancer cells, killing them through virus-mediated cytotoxicity or enhanced anticancer immune response.

    “Some virus can be genetically engineered to specifically infect and replicate in cancer cells, killing them through virusmediated cytotoxicity or enhanced anticancer immune response.”

  • The paper relies on this without support.

    Cancer gene therapy necessitates high editing efficiency.

    “As stated above, cancer gene therapy necessitates high editing efficiency, which is still beyond the reach of current CRISPR-Cas9 technologies.”
9 of 9

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?

  • CRISPR/Cas9 system has shown potentials in polygenetic diseases, such as cancer, by inhibiting oncogene expression or deactivating oncogenic virus.

    “In addition, CRISPR/Cas9 system has shown potentials in polygenetic diseases, such as cancer, by inhibiting oncogene expression or deactivating oncogenic virus [52–55].”

    From Non-viral delivery systems for CRISPR/Cas9-based genome editing: challenges and opportunities (2018) · cites this paper as [52]

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. http://www.wiley.com//legacy/wileychi/genmed/clinical/

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Authors
Xiao-Jie, L., Hui-Ying, X., Zun-Ping, K., Jin-Lian, C., & Li-Juan, J.
Affiliations
  • Department of Gastroenterology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
  • The Reproductive Center, Jiangsu Huai'an Maternity and Children Hospital, Huai'an, China
  • Department of Cardiology, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
  • Department of Gastroenterology, Shanghai Sixth People's Hospital (South), Shanghai Jiaotong University School of Medicine, Shanghai, China
  • Department of Rehabilitation, The Second People's Hospital of Huai'an, Huai'an, China
Venue
Journal of Medical Genetics
Publisher
BMJ
Published
2015-02-24
Volume
52
Issue
5
Pages
289-296
ISSN
  • 0022-2593 (ISSN-L)
  • 1468-6244
DOI
10.1136/jmedgenet-2014-102968
OpenAlex
W2140455763
Semantic Scholar
413c6dd5b848724f59fb0a72d879f29c60e250ed
Cited by
200
References
70
Citations by year
2026: 8 · 2025: 13 · 2024: 16 · 2023: 15 · 2022: 18 · 2021: 29 · 2020: 25 · 2019: 21 · 2018: 15 · 2017: 8 · 2016: 20 · 2015: 12
FWCI
1.76
Type
journal article
Language
en
Open access
Locations
  • Journal of Medical Genetics (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › CRISPR and Genetic Engineering
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Virus-based gene therapy research
  • Health Sciences › Medicine › Oncology › CAR-T cell therapy research
Keywords
CRISPR/Cas9, gene therapy, genome editing, monogenic disorders, cancer gene therapy, oncosuppressor genes, multiplex genome editing, RNA-guided nucleases
MeSH terms
Animals, Cell Line, Humans, Genetic Therapy, Genome, RNA Editing, Gene Transfer Techniques, Models, Animal, Clustered Regularly Interspaced Short Palindromic Repeats

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.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-10.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-10.

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 ›

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