基于蛋白组学研究线粒体靶向化合物抑制肝癌的作用机制

The new cases and mortality rate of hepatoma in our country are the highest in the world, but the treatment is not satisfactory. The naphthalimide compounds have good antitumor activities and promising prospects for application. Previous study indicated that the naphthalimide-flavonoid conjugate (named as compound 6c) modified by polyamine had significant antitumor activity and good safety. Compound 6c selectively inhibited hepatoma cells rather than normal hepatocytes, which was related with the generation of reactive oxygen species (ROS), but the detailed mechanism is unclear. To this end, we conducted further studies, the results of proteomics showed that compound 6c could regulate the expression of multiple proteins depending on ROS, in which p62/SQSTM1 and cathepsin D (CTSD) were the two proteins with more obvious changes. The results of molecular docking assay displayed that compound 6c had the ability to bind to mitochondrial complex II. Therefore, in this project, we will deeply explore the mechanism through which compound 6c inhibits hepatoma based on the obtained results. The experiments will be carried out according to the data from proteomics, the source of ROS and the mechanism of autophagy and lysosome which is regulated by ROS. These results of this project will illustrate the mechanism of naphthalimide compounds inhibiting cancers from a new perspective, and provide a certain degree of theoretical foundation for the clinical application of compound 6c.

我国的肝癌新增病例和死亡人数居世界首位，但治疗效果不理想。萘酰亚胺类化合物具有良好的抗肿瘤活性和应用前景。已有的研究显示多胺修饰的萘酰亚胺-黄酮缀合物(以下称化合物6c)具有显著的抗肿瘤活性和良好的安全性。化合物6c选择性地抑制肝癌细胞而非正常肝细胞的活性与活性氧(ROS)的生成有关，但具体的作用机制尚不清楚。为此，我们开展了进一步研究，蛋白组学结果显示该化合物能够依赖ROS调控多个蛋白的表达, p62/SQSTM1和cathepsin D (CTSD)是其中变化较为明显的两个蛋白质。分子对接实验结果显示该化合物能够结合线粒体复合体Ⅱ。因此拟申请本项目，在已有结果基础上，以蛋白组学结果为切入点，以ROS来源及ROS介导的自噬和溶酶体信号途径为主线，深层次研究化合物6c抑制肝癌的分子机制。研究结果将从新的角度认识萘酰亚胺类化合物的抗肿瘤机制，并为化合物6c的抗肿瘤临床应用提供一定的理论支持。

我国的肝癌新增病例和死亡人数居世界首位，但治疗效果不理想。萘酰亚胺类化合物具有良好的抗肿瘤活性和应用前景。已有的研究显示多胺修饰的萘酰亚胺-黄酮缀合物(以下称化合物6c)具有显著的抗肿瘤活性和良好的安全性。化合物6c选择性地抑制肝癌细胞而非正常肝细胞的活性与活性氧(ROS)的生成有关，但具体的作用机制尚不清楚。为此，我们开展了进一步研究，蛋白组学结果显示该化合物能够依赖ROS调控多个蛋白的表达，p62/SQSTM1和cathepsinD (CTSD)是其中变化较为明显的两个蛋白质。分子对接实验结果显示该化合物能够结合线粒体复合体Ⅱ。本项目以蛋白组学结果为切入点，以ROS来源及ROS介导的自噬和溶酶体信号途径为主线，深层次研究了化合物6c抑制肝癌的分子机制。研究结果表明，化合物6c能够诱导线粒体ROS的产生，并能导致线粒体和溶酶体功能失调。化合物6c依赖ROS抑制细胞增殖，诱导自噬体形成、细胞凋亡和DNA损伤。研究结果从新的角度认识萘酰亚胺类化合物的抗肿瘤机制，并为化合物6c的抗肿瘤临床应用提供了一定的理论支持。