线粒体反义肽核酸-三苯磷化合物靶向调控肺癌干细胞化疗敏感性的机制研究

肿瘤干细胞高耐药性常导致化疗失败，提升其活性氧(ROS)是增强化疗敏感性的重要策略之一。新近研究表明ROS是细胞自噬的主要诱因，而自噬在细胞耐药中的作用尚有争议。我们前期发现，构建的线粒体反义肽核酸-三苯磷化合物（PNA-TPP）可明显靶向激活肺癌干细胞内ROS浓度，但调控机制尚不明确。本课题推测： PNA-TPP通过靶向干扰肺癌干细胞氧化磷酸化，激活细胞内ROS浓度，并诱导细胞自噬发生，共同影响肺癌干细胞化疗耐药。本研究拟通过肺癌干细胞培养和裸鼠荷瘤模型，并分别采用RealTime-PCR、Western blot、基因转染及siRNA基因沉默等技术，从分子、细胞和组织、动物整体水平探索低ROS维持肺癌干细胞耐药特性的作用，分析PNA-TPP促ROS生成过程中的作用及相关机制，并进一步阐明ROS诱导肺癌干细胞自噬发生机制及自噬对化疗耐药的影响，为靶向提高肺癌干细胞化疗敏感性提供新的思

High chemoresistance of cancer stem cells (CSCs) was main cause of chemotherapy failure. However, raising the concentration of reactive oxygen species (ROS) in tumor cells is one of the feasible strategies to enhance chemotherapy sensitivity. ROS is the principal cause of autophagy, and recent studies have indicated that autophagy make contribution to chemoresistance of tumor cells. Based on our preliminary researches that human lung adenocarcinoma stem cells were on states with low ROS levels, and peptide nucleic acid-three benzene phosphorus compounds (PNA-TPP) could obviously increase the ROS concentration in lung adenocarcinoma stem cells. We hypothesize PNA-TPP ,which is delivered to lung cancer stem cells (LCSCs) mitochondria selectively and interfer the mitochondria oxidative phosphorylation, would increases ROS levels and induces autophagy of LCSCs, which enhancing chemotherapy resistance of LCSCs subsequently. In this study, we will explore the function of the effect of low ROS level on the drug resistance of LCSCs and investigate the mechanisms of ROS generation process by PNA-TPP, adopting the technology of RealTime-PCR,Western blot,gene transfection and siRNA respectively in nude mouse transplantation tumor model and in vitro. Furthermore, we will clarify the effect of autophagy induced by ROS in LCSCs and its chemotherapy resistance. These finds may be supplying a new way to lung cancer treatment though improve the chemotherapy sensitivity of lung cancer stem cells.