ATM抑制剂选择性杀伤SETD2缺失型肾癌的协同致死机制研究

Renal cancer is one of the most common urologic cancers characterized by malignant biological features of local proliferation, infiltration, metastasis and resistance to radiotherapy and chemotherapy. One of the important mechanisms for the development of renal cancer is the expression of tumor associated genes associated with epigenetic mutations. Therefore, the research object is to determine SETD2 by analyzing the gene mutation data in TCGA. Previous studies have found that SETD2 mutation is often accompanied by enhanced drug resistance of the sunitinib and ATM inhibitor KU55933 can specifically kill H3K36me3 deficient kidney cancer caused by SETD2 mutation. RRM2 is regulated by ATM and SETD2. It was assumed that there was a synthetic lethal effect between ATM and SETD2, and RRM2 was the target of ATM and SETD2 to play a synthetic lethal function. We will systematically study the synthetic lethal mechanism between the ATM and SETD2 genes on the molecular, cell and animal levels. Besides, the mutation spectrum of circulating tumor DNA in peripheral blood test for the early diagnosis of the gene mutation type of renal carcinoma, which is expected to improve the level of early diagnosis of renal cell carcinoma and improve the accuracy of the treatment of renal cell carcinoma. Furthermore, a new method is provided for the individualized treatment of H3K36me3 deficient kidney cancer caused by SETD2 mutation.

肾癌是以局部增殖、浸润伴转移生长及放、化疗耐受为特征的泌尿系统常见肿瘤之一。表观基因突变所伴随的肿瘤相关基因的表达异常是肾癌发生发展的重要机制之一。本课题前期通过分析TCGA中突变数据确定SETD2为研究对象。通过前期研究发现SETD2突变常伴随着舒尼替尼的耐药性增强，ATM抑制剂KU55933能特异性杀伤SETD2突变导致的H3K36me3缺失型肾癌，RRM2同时受ATM和SETD2的调控。据此推测，ATM和SETD2之间存在协同致死效应，RRM2作为ATM和SETD2共同作用的靶点从而发挥协同致死功能。我们将以ATM和SETD2为目标在分子、细胞、动物水平上系统地研究二者之间的协同致死机制。此外，利用循环肿瘤DNA的突变谱对肾癌的基因突变类型进行早期诊断，有望改善肾癌的早期诊断水平并提高肾癌治疗的精准度；为SETD2突变导致的H3K36me3缺失型肾癌的个体化治疗提供一种新方法。

肾癌发生发展的分子机制非常复杂，基于肿瘤突变谱分析，选择以SETD2为出发点，遵循“协同致死”效应理论基础，挖掘出与SETD2相协同的致死对基因，以期为肾癌的个体化治疗提供新的策略。.从肾癌中突变频率高的表观基因SETD2出发，充分利用公共数据库资源，确定SETD2的协同致死基因：ATM。从分子机制上阐述ATM抑制剂KU55933杀伤SETD2缺失型肾癌。在ccRCC中,通过蛋白质免疫印迹分析和克隆形成，流式细胞术和免疫荧光技术检测到SETD2低表达联合应用ATM抑制剂抑制细胞增殖并促进细胞凋亡，影响细胞周期。应用染色质免疫共沉淀（ChIP-qPCR）技术分析H3K36me3、E2F1与RRM2之间调控关系；体内裸鼠成瘤实验验证ATM抑制剂对SETD2缺失型肾癌的致死作用。