线粒体分裂前复合体参与线粒体融合介导的胆管癌顺铂耐药机制的研究

The chemotherapy on the advanced cholangiocarcinoma mainly depends on cisplatin, however, with limited clinical outcomes. Apoptosis evasion plays an important role in the cisplatin resistance of tumors. Mitochondrial fusion can contribute to the inhibition of the mitochondrial apoptosis pathway, and fission functions on the opposite. The effective formation of the pre-fission complexes determines whether Drp1 can be recruited to mitochondria, therefore it was suggested to be the main process participating in the early regulation of mitochondrial fission and fusion. But whether fusion mediates cisplatin resistance and whether pre-fission complexes involve in it remain to be solved. Our previous study showed that low dose of cisplatin led to the mitochondrial fusion in cholangiocarcinoma cells with the decreased localization of Drp1 on mitohcondria, and when the fusion was reversed to fission, obvious apoptosis emerged. Taken together, we purposed that mitochondrial fusion might mediate cisplatin resistance of cholangiocarcinoma, and effective pre-fission complexes formation contributing to the right localization of Drp1 might be the up stream of it. This issue will utilize gene knockdown and immunofluorescence, to assure the relationship between mitochondrial fusion and cisplatin resistance, illustrate the role of pre-fission complexes playing on the mitochondrial morphology and cisplatin resistance, and to provide the theoretical basis and experimental information for the development of novel targeting agents and potential therapies for the reverse of tumor chemotherapy resistance.

晚期胆管癌化疗主要依赖于顺铂，但临床效果欠佳。凋亡逃逸是肿瘤顺铂耐药的重要机制之一。线粒体融合可抑制线粒体凋亡途径的激活，线粒体分裂则作用相反。线粒体分裂前复合体能否有效形成，决定分裂蛋白Drp1能否有效募集至线粒体，因此认为其可能是调控线粒体分裂/融合的早期重要环节。但线粒体融合是否参与顺铂耐药及分裂前复合体是否在其中发挥作用尚不清楚。我们前期发现低剂量顺铂可促进胆管癌细胞的线粒体融合增加，且Drp1线粒体定位明显减少，逆转融合为分裂后，细胞凋亡显著增加。因此，我们推测线粒体融合可能参与胆管癌顺铂耐受，分裂前复合体能否有效形成，从而影响Drp1向线粒体定位可能是其上游调控机制。本课题拟采用基因沉默、免疫荧光等技术手段，明确线粒体融合与胆管癌顺铂耐药关系，阐明分裂前复合体于上游调节线粒体形态，参与胆管癌顺铂耐药。为开发逆转肿瘤耐药的新型靶向药物和潜在治疗技术提供理论基础与实验依据。