Marked anti-tumour activity of the combination of YM155, a novel survivin suppressant,and platinum-based drugs

Background:

Survivin, a member of the inhibitor of apoptosis protein family, is an attractive target for cancer therapy. We have now investigated the effects of the combination of YM155, a novel small-molecule inhibitor of survivin expression, and platinum compounds (cisplatin and carboplatin) on human non-small cell lung cancer (NSCLC) cell lines.

Methods:

The anti-cancer efficacy of YM155 in combination with platinum compounds was evaluated on the basis of cell death and progression of tumour xenografts. Platinum compound-induced DNA damage was evaluated by immunofluorescence analysis of histone γ-H2AX.

Results:

Immunofluorescence analysis of histone γ-H2AX showed that YM155 delayed the repair of double-strand breaks induced in nuclear DNA by platinum compounds. The combination of YM155 and platinum compounds also induced synergistic increases both in the number of apoptotic cells and in the activity of caspase-3. Finally, combination therapy with YM155 and platinum compounds delayed the growth of NSCLC tumour xenografts in nude mice to an extent greater than that apparent with either treatment modality alone.

Conclusion:

These results suggest that YM155 sensitises tumour cells to platinum compounds both in vitro and in vivo, and that this effect is likely attributable to the inhibition of DNA repair and consequent enhancement of apoptosis.     

2-methoxyestradiol, an endogenous mammalian metabolite, radiosensitizes colon carcinoma cells through c-Jun NH2-terminal kinase activation.

PURPOSE: 2-Methoxyestradiol (2ME), an estrogen metabolite, induces apoptosis in various cell types. We investigated whether 2ME pretreatment can radiosensitize colon adenocarcinoma cells. EXPERIMENTAL DESIGN: Radiosensitizing effects of 2ME were evaluated by cell death, clonogenic assay, nuclear fragmentation, and tumor progression of xenografts. Ionizing radiation-induced DNA damage was evaluated by histone H2AX phosphorylation and its foci. The c-Jun NH2-terminal kinase (JNK) activation was evaluated by anti-phosphorylated JNK antibody and inhibited by the JNK-specific inhibitor SP600125 or dominant-negative SEK1 expression. RESULTS: Clonogenic assays revealed that 2ME, but not estradiol, radiosensitized three colon carcinoma cells, DLD-1, HCT-8, and HCT-15, and strongly suppressed tumor progression of DLD-1 xenografts. Gene transfer-mediated Bcl-xL overexpression largely abolished both augmented apoptosis and reduced survival fractions. Pretreatment with 2ME enhanced H2AX phosphorylation, its foci, and phosphorylation of ATM kinase and delayed re-entry of cell cycle progression after ionizing radiation. Augmentation of both radiosensitivity and H2AX phosphorylation was substantially reduced by SP600125 or overexpression of a dominant-negative mutant SEK1. CONCLUSION: 2ME radiosensitized colon carcinoma cells through enhanced DNA damage via JNK activation, thereby representing a novel radiosensitizing therapy against colon cancer.     

The over-expression of survivin enhances the chemotherapeutic efficacy of YM155 in human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. The inability of chemotherapeutic drugs to selectively target HCC tumor cells because of their predominant resistant phenotype to most conventional anticancer agents bestows a major obstacle for the clinical management of HCC. In this report, we have examined and demonstrated the remarkable heterogeneity of expression of survivin and its phosphorylated active form (p-survivin) in HCC patients'' tissues and cell lines. Furthermore, the expression of survivin and p-survivin in HCC cell lines was found to be associated with response to the small-molecule survivin suppressant YM155. Therefore, in the HCC cell lines that express elevated level of survivin and p-survivin, YM155 efficiently inhibited their proliferation, induced cell cycle arrest and apoptosis resulting in DNA damage through the dysregulation of cell-cycle checkpoint-related regulatory genes. Importantly, YM155 yielded significantly better therapeutic effect than sorafenib when tested in an orthotopic mouse model using patient-derived HCC xenografts with elevated survivin and p-survivin expression. Our results clearly demonstrated that the level of survivin and p-survivin expression could serve as molecular predictive biomarkers to select potential YM155-responsive patients, in a move towards delivering precision medicine for HCC patients.     

YM155对骨肉瘤细胞系F5M2增殖和凋亡的影响

目的:探讨YM155对人骨肉瘤细胞系F5M2的作用及其机制.方法:体外培养人骨肉瘤细胞系F5M2,不同浓度YM155处理人骨肉瘤细胞系F5M2,用MTT法检测其对细胞增殖的影响;流式细胞仪检测细胞凋亡率;实时荧光定量PCR检测survivin mRNA的表达;蛋白免疫印迹法检测survivin、caspase-3蛋白的表达.结果:YM155可抑制人骨肉瘤细胞F5M2的增殖,且呈剂量依赖性.随着YM155浓度的升高,人骨肉瘤细胞F5M2凋亡率明显增加,同时能够降低survivin在 mRNA水平和蛋白水平的表达,以及激活caspase-3.结论:YM155能够有效抑制人骨肉瘤细胞F5M2增殖,并诱导其凋亡,其可能机制为下调骨肉瘤细胞系F5M2 survivin的表达,继而激活caspase凋亡信号通路.     

YM155, a selective survivin suppressant, inhibits tumor spread and prolongs survival in a spontaneous metastatic model of human triple negative breast cancer

Metastatic triple negative breast cancer [TNBC, with negative expression of estrogen and progesterone receptors and no overexpression of HER2/neu (ErbB-2)] remains a major therapeutic challenge because of its poor overall prognosis and lack of optimal targeted therapies. Survivin has been implicated as an important mediator of breast cancer cell growth and dysfunctions in apoptosis, and its expression correlates with a higher incidence of metastases and patient mortality; thus, survivin is an attractive target for novel anti-cancer agents. In previous studies, we identified YM155 as a small molecule that selectively suppresses survivin expression. YM155 inhibits the growth of a wide range of human cancer cell lines. Tumor regression induced by YM155 is associated with decreased intratumoral survivin expression, increased apoptosis and a decreased mitotic index. In the present study, we evaluated the antitumor efficacy of YM155 both in vitro and in vivo using preclinical TNBC models. We found that YM155 suppressed survivin expression, including that of its splice variants (survivin 2B, δEx3 and 3B), resulting in decreased cellular proliferation and spontaneous apoptosis of human TNBC cells. In a mouse xenograft model, continuous infusion of YM155 led to the complete regression of subcutaneously established tumors. Furthermore, YM155 reduced spontaneous metastases and significantly prolonged the survival of animals bearing established metastatic tumors in the MDA-MB-231-Luc-D3H2-LN orthotopic model. These results suggest that the survivin-suppressing activity of YM155 may offer a novel therapeutic option for patients with metastatic TNBC.     

Enhancement of in vitro and in vivo tumor cell radiosensitivity by valproic acid

Valproic acid (VA) is a well-tolerated drug used to treat seizure disorders and has recently been shown to inhibit histone deacetylase (HDAC). Because HDAC modulates chromatin structure and gene expression, parameters considered to influence radioresponse, we investigated the effects of VA on the radiosensitivity of human brain tumor cells grown in vitro and in vivo. The human brain tumor cell lines SF539 and U251 were used in our study. Histone hyperacetylation served as an indicator of HDAC inhibition. The effects of VA on tumor cell radiosensitivity in vitro were assessed using a clonogenic survival assay and gammaH2AX expression was determined as a measure of radiation-induced DNA double strand breaks. The effect of VA on the in vivo radioresponse of brain tumor cells was evaluated according to tumor growth delay analysis carried out on U251 xenografts. Irradiation at the time of maximum VA-induced histone hyperacetylation resulted in significant increases in the radiosensitivity of both SF539 and U251 cells. The radiosensitization was accompanied by a prolonged expression of gammaH2AX. VA administration to mice resulted in a clearly detectable level of histone hyperacetylation in U251 xenografts. Irradiation of U251 tumors in mice treated with VA resulted in an increase in radiation-induced tumor growth delay. Valproic acid enhanced the radiosensitivity of both SF539 and U251 cell lines in vitro and U251 xenografts in vivo, which correlated with the induction of histone hyperacetylation. Moreover, the VA-mediated increase in radiation-induced cell killing seemed to involve the inhibition of DNA DSB repair.     

YM155, a novel small-molecule survivin suppressant, induces regression of established human hormone-refractory prostate tumor xenografts

Various accumulating evidence suggests that survivin, a member of the inhibitor of apoptosis (IAP) family, plays an important role in drug resistance and cancer cell survival in many types of cancer, including hormone-refractory prostate cancer (HRPC). Here, we characterized YM155, a novel small-molecule survivin suppressant, using a survivin gene promoter activity assay. YM155 suppressed expression of survivin and induced apoptosis in PC-3 and PPC-1 human HRPC cell lines at 10 nmol/L. In contrast, YM155 up to 100 nmol/L showed little effect on expression levels of other IAP- or Bcl-2-related proteins. In a s.c. xenografted PC-3 tumor model in mice, 3-day continuous infusions of YM155 at 3 to 10 mg/kg induced massive tumor regression accompanied by suppression of intratumoral survivin. YM155 also completely inhibited the growth of orthotopically xenografted PC-3 tumors. No significant decreases in body weight were observed in mice treated with YM155 during the experimental period. Pharmacokinetic analyses indicated that YM155 is highly distributed to tumors and at concentrations approximately 20-fold higher than those in plasma. Our findings represent the first attempt to show tumor regression and suppression of survivin in p53-deficient human HRPC cells by a single small molecular compound treatment. Further extensive investigation of YM155 in many types of cancer, including HRPC, seems to be worthwhile to develop this novel therapeutic approach.     

Gefitinib radiosensitizes non-small cell lung cancer cells by suppressing cellular DNA repair capacity.

PURPOSE: Overexpression of the epidermal growth factor receptor (EGFR) promotes unregulated growth, inhibits apoptosis, and likely contributes to clinical radiation resistance of non-small cell lung cancer (NSCLC). Molecular blockade of EGFR signaling is an attractive therapeutic strategy for enhancing the cytotoxic effects of radiotherapy that is currently under investigation in preclinical and clinical studies. In the present study, we have investigated the mechanism by which gefitinib, a selective EGFR tyrosine kinase inhibitor, restores the radiosensitivity of NSCLC cells. EXPERIMENTAL DESIGN: Two NSCLC cell lines, A549 and H1299, were treated with 1 micromol/L gefitinib for 24 h before irradiation and then tested for clonogenic survival and capacity for repairing DNA double strand breaks (DSB). Four different repair assays were used: host cell reactivation, detection of gamma-H2AX and pNBS1 repair foci using immunofluorescence microscopy, the neutral comet assay, and pulsed-field gel electrophoresis. RESULTS: In clonogenic survival experiments, gefitinib had significant radiosensitizing effects on both cell lines. Results from all four DNA damage repair analyses in cultured A549 and H1299 cells showed that gefitinib had a strong inhibitory effect on the repair of DSBs after ionizing radiation. The presence of DSBs was especially prolonged during the first 2 h of repair compared with controls. Immunoblot analysis of selected repair proteins indicated that pNBS1 activation was prolonged by gefitinib correlating with its effect on pNBS1-labeled repair foci. CONCLUSIONS: Overall, we conclude that gefitinib enhances the radioresponse of NSCLC cells by suppressing cellular DNA repair capacity, thereby prolonging the presence of radiation-induced DSBs.     

Induction of autophagy-dependent apoptosis by the survivin suppressant YM155 in prostate cancer cells

In this study, we demonstrated that YM155, a novel survivin suppressant, induced both apoptosis, and autophagy that was shown by conversion of cytosolic-associated protein light chain 3 (LC3I) into autophagosome-associated form (LC3II) and a punctate fluorescence pattern of an ectopic GFP-LC3 protein. The lysosomal inhibitor chloroquine further accumulated YM155-induced LC3II, indicating an increase of autophagic flux. Ectopic expression of survivin significantly attenuated YM155-induced apoptosis and autophagy, whereas survivin siRNA induced autophagy. Furthermore, inhibition of either early or late events of autophagy attenuated YM155-induced apoptosis, demonstrating that induction of autophagy proceeds apoptosis. In conclusion, suppression of survivin by YM155 induces autophagy-dependent apoptosis, and YM155-induced autophagy plays a pro-apoptotic role thereby unveiling a novel mechanism of YM155 in prostate cancer cells.     

YM155对肝癌HepG2细胞增殖和凋亡的影响

目的:探讨YM155对肝癌HepG2细胞增殖和凋亡的影响及可能的机制。方法:采用CCK-8法检测细胞生长抑制率；应用流式细胞仪检测细胞凋亡率的变化；Western blot法检测细胞中蛋白表达的变化，实时定量RT-PCR检测survivin mRNA表达的变化。结果:YM155对人肝癌HepG2细胞的生长抑制作用呈现剂量和时间依赖性。流式细胞术结果显示，HepG2细胞凋亡率明显升高,呈现剂量依赖性。YM155可引起survivin mRNA及蛋白表达下降，而caspase-3、caspase-9和PARP蛋白表达上升。结论:YM155可以抑制人肝癌HepG2细胞的增殖并促进其凋亡，其机制可能是通过激活caspase凋亡途径来实现。     

Histone deacetylase inhibitors radiosensitize human melanoma cells by suppressing DNA repair activity.

PURPOSE: Histone deacetylase (HDAC) inhibitors have emerged recently as promising anticancer agents. They arrest cells in the cell cycle and induce differentiation and cell death. The antitumor activity of HDAC inhibitors has been linked to their ability to induce gene expression through acetylation of histone and nonhistone proteins. However, it has recently been suggested that HDAC inhibitors may also enhance the activity of other cancer therapeutics, including radiotherapy. The purpose of this study was to evaluate the ability of HDAC inhibitors to radiosensitize human melanoma cells in vitro. EXPERIMENTAL DESIGN: A panel of HDAC inhibitors that included sodium butyrate (NaB), phenylbutyrate, tributyrin, and trichostatin A were tested for their ability to radiosensitize two human melanoma cell lines (A375 and MeWo) using clonogenic cell survival assays. Apoptosis and DNA repair were measured by standard assays. RESULTS: NaB induced hyperacetylation of histone H4 in the two melanoma cell lines and the normal human fibroblasts. NaB radiosensitized both the A375 and MeWo melanoma cell lines, substantially reducing the surviving fraction at 2 Gy (SF2), whereas it had no effect on the normal human fibroblasts. The other HDAC inhibitors, phenylbutyrate, tributyrin, and trichostatin A had significant radiosensitizing effects on both melanoma cell lines tested. NaB modestly enhanced radiation-induced apoptosis that did not correlate with survival but did correlate with functional impairment of DNA repair as determined based on the host cell reactivation assay. Moreover, NaB significantly reduced the expression of the repair-related genes Ku70 and Ku86 and DNA-dependent protein kinase catalytic subunit in melanoma cells at the protein and mRNA levels. Normal human fibroblasts showed no change in DNA repair capacity or levels of DNA repair proteins following NaB treatment. We also examined gamma-H2AX phosphorylation as a marker of radiation response to NaB and observed that compared with controls, gamma-H2AX foci persisted long after ionizing exposure in the NaB-treated cells. CONCLUSIONS: HDAC inhibitors radiosensitize human tumor cells by affecting their ability to repair the DNA damage induced by ionizing radiation and that gamma-H2AX phosphorylation can be used as a predictive marker of radioresponse.     

A combination of YM-155, a small molecule survivin inhibitor,and IL-2 potently suppresses renal cell carcinoma in murine model

YM155, a small molecule inhibitor of the antiapoptotic protein survivin, has been developed as a potential anti-cancer drug. We investigated a combination therapy of YM155 and interleukin-2 (IL-2) in a mouse model of renal cell carcinoma (RCC). YM155 caused cell cycle arrest and apoptosis in renal cancer (RENCA) cells. Next, luciferase-expressing RENCA cells were implanted in the left kidney and the lung of BALB/c mice to develop RCC metastatic model. In this orthotopic renal and metastatic lung tumors models, YM155 and IL-2 additively decreased tumor weight, lung metastasis, and luciferin-stained tumor images. Also, the combination significantly suppressed regulatory T cells and myeloid-derived suppressor cells compared with single agent treatment. We suggest that a combination of YM155 and IL-2 can be tested as a potential therapeutic modality in patients with RCC.     

Suppression of Rotenone-Treated Human Breast Cancer Stem Cell Survival Using Survivin Inhibitor YM155 is Associated to Oxidative Stress Modulation

Background: Despite recent progress in molecular-targeted therapies, breast cancer remains the primary leading cause of cancer related death among women worldwide. Breast cancer stem cells (BCSCs) are believed to be responsible for therapy resistance and cancer recurrence. We recently demonstrated that human BCSCs (CD24-/CD44+) could survive better than their counterpart non-BCSCs (CD24-/CD44-) when treated with rotenone, possibly due to lower levels of reactive oxygen species (ROS) production, high expression of antioxidant manganese superoxide dismutase (MnSOD), and anti-apoptotic survivin. The aim of this study was to verify the role of survivin on human BCSCs survival under oxidative stress modulation by suppressing its expression using YM155, a survivin inhibitor. Methods: Human BCSCs (ALDH+ cells) were treated with YM155 for 24 h prior to treatment with rotenone for a further 6 h. We determined intracellular superoxide levels were determined using dihydroethidium assay, survivin and MnSOD expression using qRT-PCR, survivin protein level using ELISA, as well as cell viability using trypan blue exclusion and acridine orange/ethidium bromide apoptosis assay. Results: Suppression of survivin expression using YM155 could reduce the survival of rotenone-treated BCSCs, which may be associated with oxidative stress modulation, as shown by increased ROS levels and decreased MnSOD expression. We confirm that survivin is responsible for maintaining BCSCs survival under oxidative stress modulation. Furthermore, YM155 could modulate oxidative stress in BCSCs by reducing MnSOD expression and increasing ROS levels. Conclusion: YM155 treatment could be used to overcome BCSCs resistance to oxidative stress-based anticancer therapies.     

Differential response of human glioblastoma cell lines to combined camptothecin and ionizing radiation treatment

In order to enhance the cytotoxicity of radiation, camptothecin (CPT), an inhibitor of DNA topoisomerase I, was added to the cultured glioma cell lines before irradiation (IR). Radiation responses of five glioblastoma cell lines (U87-MG, U373-MG, GHE, GaMG and SNB-19) treated with CPT were analyzed in terms of cell and colony counts, cell cycle progression, expression of histone gamma H2AX, DNA repair protein Rad50, survivin, cleaved caspase 3, p53 and of topoisomerase I. CPT enhanced the radiotoxicity in U87-MG and SNB-19 cell lines if cell and colony counts were used as the end-points. In contrast, pre-treatment with CPT of U373-MG, GHE and GaMG cell lines did not enhance cytotoxicity of IR in terms of cell and colony counts but accelerated DNA damage repair assessed by Rad50 foci. CPT treated glioma cells revealed at least two subpopulations with respect to the expression of histone gamma H2AX, a marker of DNA double-strand breaks. The cell lines tested also differed in the expression of survivin, cleaved caspase 3, p53 and of topoisomerase I. The failure of CPT to enhance the radiotoxicity of glioma U373-MG, GHE and GaMG cell lines in terms of cell and colony counts was found to correlate with accelerated DNA damage repair, and with low expression of topoisomerase I, a target of CPT.     

Broad spectrum and potent antitumor activities of YM155, a novel small-molecule survivin suppressant, in a wide variety of human cancer cell lines and xenograft models

Antitumor activities of YM155, a novel small-molecule survivin suppressant, were investigated in a wide variety of human cancer cell lines and xenograft models. YM155 inhibited the growth of 119 human cancer cell lines, with the greatest activity in lines derived from non-Hodgkin's lymphoma, hormone-refractory prostate cancer, ovarian cancer, sarcoma, non-small-cell lung cancer, breast cancer, leukemia and melanoma. The mean log growth inhibition of 50% (GI(50) ) value was 15 nM. The mean GI(50) values of YM155 were 11 nM for p53 mut/null cell lines and 16 nM for p53 WT cell lines, suggesting that YM155 inhibits the growth of human tumor cell lines regardless of their p53 status. In non-small-cell lung cancer (Calu 6, NCI-H358), melanoma (A375), breast cancer (MDA-MB-231) and bladder cancer (UM-UC-3) xenograft models, 3- or 7-day continuous infusions of YM155 (1-10 mg/kg) demonstrated significant antitumor activity without showing significant bodyweight loss. Tumor regressions induced by YM155 were associated with reduced intratumoral survivin expression levels, increased apoptosis and decreased mitotic indices. The broad and potent antitumor activity presented in the present study is indicative of the therapeutic potential of YM155 in the clinical setting.     

Inhibition of poly(ADP-ribose) polymerase enhances cell death and improves tumor growth delay in irradiated lung cancer models.

PURPOSE: Poly(ADP-ribose) polymerase-1 (PARP-1) is the founding member of a family of enzymes that catalyze the addition of ADP-ribose units to proteins that mediate DNA repair pathways. Ionizing radiation induces DNA strand breaks, suggesting that PARP-1 inhibition may sensitize tumor cells to radiation. EXPERIMENTAL DESIGN: We investigated the combination of PARP-1 inhibition with radiation in lung cancer models. ABT-888, a novel potent PARP-1 inhibitor, was used to explore the effects of PARP-1 inhibition on irradiated tumors and tumor vasculature. RESULTS: ABT-888 reduced clonogenic survival in H460 lung cancer cells, and inhibited DNA repair as shown by enhanced expression of DNA strand break marker histone gamma-H2AX. Both apoptosis and autophagy contributed to the mechanism of increased cell death. Additionally, ABT-888 increased tumor growth delay at well-tolerated doses in murine models. For a 5-fold increase in tumor volume, tumor growth delay was 1 day for ABT-888 alone, 7 days for radiation alone, and 13.5 days for combination treatment. Immunohistochemical staining of tumor sections revealed an increase in terminal deoxyribonucleotide transferase-mediated nick-end labeling apoptotic staining, and a decrease in Ki-67 proliferative staining after combination treatment. Matrigel assay showed a decrease in in vitro endothelial tubule formation with ABT-888/radiation combination treatment, and von Willebrand factor staining of tumor sections revealed decreased vessel formation in vivo, suggesting that this strategy may also target tumor angiogenesis. CONCLUSIONS: We conclude that PARP-1 inhibition shows promise as an effective means of enhancing tumor sensitivity to radiation, and future clinical studies are needed to determine the potential of ABT-888 as a radiation enhancer.     

YM155 sensitizes triple‐negative breast cancer to membrane‐bound TRAIL through p38 MAPK‐ and CHOP‐mediated DR5 upregulation

Because available treatments have limited efficacy in triple‐negative breast cancer (TNBC), the identification of new therapeutic strategies to improve patients' outcome is urgently needed. In our study, we investigated the effects of the administration of the small molecule selective survivin suppressant YM155, alone or in association with CD34+ cells transduced with a replication‐deficient adenovirus encoding the human tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) gene (CD34‐TRAIL+ cells), in three TNBC cell models. YM155 exposure significantly impaired TNBC cell growth and selectively modulated survivin expression at both mRNA and protein level. In addition, co‐culturing YM155‐treated TNBC cells with CD34‐TRAIL+ cells resulted in markedly increased cytotoxic effect and apoptotic response in comparison with single treatments. Such a chemosensitizing effect was observed only in TNBC cells inherently expressing DR5 and relied on the ability of YM155 to upregulate DR5 expression through a p38 MAPK‐ and CHOP‐dependent mechanism. YM155/CD34‐TRAIL+ combination also showed a significant inhibitory effect on the growth of DR5‐expressing TNBC cells following xenotransplantation into NOD/SCID mice, in the absence of toxicity. Overall, our data (i) provide, for the first time, evidence that YM155 sensitizes TNBC cells to CD34‐TRAIL+ cells‐induced apoptosis by a mechanism involving the downregulation of survivin and the simultaneous p38 MAPK‐ and CHOP‐mediated upregulation of DR5, and (ii) suggest the combination of YM155 with TRAIL‐armed CD34+ progenitor cells as a promising therapeutic option for patients with TNBC expressing DR5.     

非小细胞肺癌细胞中OGG1调控顺铂诱导的细胞毒性的作用机制探讨

目的:探讨8-氧鸟嘌呤DNA糖基化酶(OGG1)在人肺癌细胞中调控顺铂诱导的细胞毒性的作用机制。方法:采用酶联免疫吸附试验、免疫印迹、流式细胞术和免疫荧光法、线粒体拷贝数和膜电位检测等方法,进行相关实验。结果:顺铂可诱导8-羟基-2'-脱氧鸟苷（8-OHdG）浓度升高,8-OHdG的浓度及细胞凋亡分别与OGG1 mRNA的表达存在显著相关性。外源性表达OGG1促进其DNA修复活性,可降低顺铂诱导的8-OHdG水平,提高非小细胞肺癌（non-small cell lung cancer,NSCLC）细胞活力,并抑制顺铂诱导的NSCLC细胞凋亡,而OGG1沉默则表现相反的结果。此外,过表达OGG1减少顺铂导致的线粒体DNA损伤和功能障碍,沉默OGG1增强顺铂诱导的MAPK/p38通路的激活,导致NSCLC细胞发生凋亡。结论:OGG1的下调有利于提高肺癌细胞对顺铂的敏感性。因此,本研究通过在体外证实OGG1介导的DNA修复在顺铂耐药中的作用,为肺癌的治疗提供了理论支持。