Ni Pan, Xu Wenxia, Zhang Yajie, Chen Qi, Li Aiping, Wang Shouyu, Xu Shan, Zhou Jianwei
Department of Cell Biology, School of Basic Medical Sciences, Nanjing Medical University.
Curr Cancer Drug Targets. 2015;14(9):850-9. doi: 10.2174/1568009614666141028094612.
Cisplatin is one of the most commonly used drugs in the treatment of gastric cancer. However, drug resistance is a major obstacle for effective treatment and originates in multiple mechanisms such as enhanced DNA repair and anti-apoptosis. Our previous results demonstrated that XRCC1 was a key regulator of cisplatin induced DNA damage and apoptosis. TXNL1, a member of the thioredoxin family, negatively regulated the expression of XRCC1 via the ubiquitin-proteasome pathway. Here, we investigated the role of TXNL1 in the apoptosis induced by cisplatin. Our data showed that the expression of TXNL1 in the cisplatin resistant gastric cancer cell lines BGC823/DDP and SGC7901/DDP cells was significantly lower compared with the cisplatin sensitive cell lines BGC823 and SGC7901. Inhibition of the expression of TXNL1 in BGC823 and SGC7901 cells led to increased resistance to cisplatin induced apoptosis and cell death detected by Tunel and clonogenic assay, respectively. In contrast, over expression of TXNL1 in BGC823/DDP and SGC7901/DDP cells lead to higher cisplatin induced apoptosis and cell death. Moreover, our results demonstrated that the mechanism of TXNL1 regulating cisplatin-induced apoptosis was closely associated with Bcl-2 mediated mitochondria apoptosis pathway. In conclusion, these findings suggest that TXNL1 was a feasible modulator and potential chemotherapeutic target for the cisplatin resistant phenotype of human gastric cancer cells.
顺铂是治疗胃癌最常用的药物之一。然而,耐药性是有效治疗的主要障碍,其产生涉及多种机制,如DNA修复增强和抗凋亡。我们之前的结果表明,XRCC1是顺铂诱导的DNA损伤和凋亡的关键调节因子。硫氧还蛋白家族成员TXNL1通过泛素-蛋白酶体途径负向调节XRCC1的表达。在此,我们研究了TXNL1在顺铂诱导的凋亡中的作用。我们的数据显示,与顺铂敏感细胞系BGC823和SGC7901相比,顺铂耐药胃癌细胞系BGC823/DDP和SGC7901/DDP中TXNL1的表达显著降低。分别通过Tunel和克隆形成试验检测发现,抑制BGC823和SGC7901细胞中TXNL1的表达会导致对顺铂诱导的凋亡和细胞死亡的抗性增加。相反,在BGC823/DDP和SGC7901/DDP细胞中过表达TXNL1会导致更高的顺铂诱导的凋亡和细胞死亡。此外,我们的结果表明,TXNL1调节顺铂诱导的凋亡的机制与Bcl-2介导的线粒体凋亡途径密切相关。总之,这些发现表明TXNL1是人类胃癌细胞顺铂耐药表型的可行调节因子和潜在化疗靶点。