Suppression of Rev3, the catalytic subunit of Pol?, sensitizes drug-resistant lung tumors to chemotherapy

The Koch Institute for Integrative Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 11/2010; 107(48):20786-91. DOI: 10.1073/pnas.1011409107
Source: PubMed


Platinum-based chemotherapeutic drugs are front-line therapies for the treatment of non-small cell lung cancer. However, intrinsic drug resistance limits the clinical efficacy of these agents. Recent evidence suggests that loss of the translesion polymerase, Polζ, can sensitize tumor cell lines to cisplatin, although the relevance of these findings to the treatment of chemoresistant tumors in vivo has remained unclear. Here, we describe a tumor transplantation approach that enables the rapid introduction of defined genetic lesions into a preclinical model of lung adenocarcinoma. Using this approach, we examined the effect of impaired translesion DNA synthesis on cisplatin response in aggressive late-stage lung cancers. In the presence of reduced levels of Rev3, an essential component of Polζ, tumors exhibited pronounced sensitivity to cisplatin, leading to a significant extension in overall survival of treated recipient mice. Additionally, treated Rev3-deficient cells exhibited reduced cisplatin-induced mutation, a process that has been implicated in the induction of secondary malignancies following chemotherapy. Taken together, our data illustrate the potential of Rev3 inhibition as an adjuvant therapy for the treatment of chemoresistant malignancies, and highlight the utility of rapid transplantation methodologies for evaluating mechanisms of chemotherapeutic resistance in preclinical settings.

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Available from: Trudy Gale Oliver
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    • "Rev1-Polζ complex is not only indispensible for most translesion DNA synthesis events (Shachar et al., 2009; Livneh et al., 2010) but also functions in many DNA repair pathways (Okada et al., 2005) such as DNA interstrand crosslink repair (Räschle et al., 2008) and homologous recombination repair (Sharma et al., 2011). Studies have increasingly indicated that defects in REV3 and REV1 genes are closely related to the development of tumors and the drug resistance of cancer cells (Lin et al., 2006; Dumstorf et al., 2009; Doles et al., 2010; Xie et al., 2010). Moreover, the Fanconi anemia pathway regulates translesion synthesis activity through an interaction between monoubiquitinated Rev1 and the Fanconi anemia core complex (Kim et al., 2012). "
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    ABSTRACT: In addition to DNA repair pathways, cells utilize translesion DNA synthesis (TLS) to bypass DNA lesions during replication. During TLS, Y-family DNA polymerase (Polη, Polκ, Polı and Rev1) inserts specific nucleotide opposite preferred DNA lesions, and then Polζ consisting of two subunits, Rev3 and Rev7, carries out primer extension. Here, we report the complex structures of Rev3-Rev7-Rev1(CTD) and Rev3-Rev7-Rev1(CTD)-Polκ(RIR). These two structures demonstrate that Rev1(CTD) contains separate binding sites for Polκ and Rev7. Our BIAcore experiments provide additional support for the notion that the interaction between Rev3 and Rev7 increases the affinity of Rev7 and Rev1. We also verified through FRET experiment that Rev1, Rev3, Rev7 and Polκ form a stable quaternary complex in vivo, thereby suggesting an efficient switching mechanism where the "inserter" polymerase can be immediately replaced by an "extender" polymerase within the same quaternary complex.
    Preview · Article · Nov 2012 · Protein & Cell
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    • "Given their critical role in the FA pathway, TLS polymerases are possible targets for augmenting the effect of DNA cross-linking chemotherapeutic agents. Depletion of Rev1 or Rev3 causes pronounced sensitivity to cisplatin in lymphoma and non-small-cell lung cancer (NSCLC) models and prevents the development of acquired drug resistance, indicating that inhibition of TLS can not only kill tumor cells, but also antagonize TLS-mediated generation of resistance-causing mutations (Doles et al. 2010; Xie et al. 2010). Thus, selectively inhibiting TLS polymerases may sensitize cancer cells to DNA-damaging agents. "
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    ABSTRACT: The maintenance of genome stability is critical for survival, and its failure is often associated with tumorigenesis. The Fanconi anemia (FA) pathway is essential for the repair of DNA interstrand cross-links (ICLs), and a germline defect in the pathway results in FA, a cancer predisposition syndrome driven by genome instability. Central to this pathway is the monoubiquitination of FANCD2, which coordinates multiple DNA repair activities required for the resolution of ICLs. Recent studies have demonstrated how the FA pathway coordinates three critical DNA repair processes, including nucleolytic incision, translesion DNA synthesis (TLS), and homologous recombination (HR). Here, we review recent advances in our understanding of the downstream ICL repair steps initiated by ubiquitin-mediated FA pathway activation.
    Preview · Article · Jul 2012 · Genes & development
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    • "The overall cellular response to platinum-DNA intrastrand cross-links and ICLs involves multiple processes that ultimately determine cell fate. We and others have identified TLS as an important pathway influencing cisplatin-induced cytotoxicity (Simpson and Sale, 2003; Sonoda et al., 2003; Bassett et al., 2004; Niedzwiedz et al., 2004; Wu et al., 2004; Albertella et al., 2005; Nojima et al., 2005; Okuda et al., 2005; Chen et al., 2006; Doles et al., 2010; Hicks et al., 2010). The TLS pathway promotes tolerance to various DNA lesions that block replicative polymerases and is triggered by the monoubiquitination of proliferating cell nuclear antigen (PCNA) by the RAD6 (E2)⅐RAD18 (E3) complex (Waters et al., 2009). "
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    ABSTRACT: Oxaliplatin, satraplatin, and picoplatin are cisplatin analogs that interact with DNA forming intrastrand and interstrand DNA cross-links (ICLs). Replicative bypass of cisplatin DNA adducts requires the cooperative actions of at least three translesion DNA synthesis (TLS) polymerases: Polη, REV1, and Polζ. Because oxaliplatin, satraplatin, and picoplatin contain bulkier chemical groups attached to the platinum core compared with cisplatin, we hypothesized that these chemical additions may impede replicative bypass by TLS polymerases and reduce tolerance to platinum-containing adducts. We examined multiple responses of cancer cells to oxaliplatin, satraplatin, or picoplatin treatment under conditions where expression of a TLS polymerase was limited. Our studies revealed that, although Polη contributes to the tolerance of cisplatin adducts, it plays a lesser role in promoting replication through oxaliplatin, satraplatin, and picoplatin adducts. REV1 and Polζ were necessary for tolerance to all four platinum analogs and prevention of hyperactivation of the DNA damage response after treatment. In addition, REV1 and Polζ were important for the resolution of DNA double-stranded breaks created during replication-associated repair of platinum-containing ICLs. Consistent with ICLs being the predominant cytotoxic lesion, depletion of REV1 or Polζ rendered two different model cell systems extremely sensitive to all four drugs, whereas Polη depletion had little effect. Together, our data suggest that REV1 and Polζ are critical for promoting resistance to all four clinically relevant platinum-based drugs by promoting both translesion DNA synthesis and DNA repair.
    Full-text · Article · Mar 2012 · Molecular pharmacology
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