依维莫司让许多晚期肾癌患者生存获益，但获得性耐药导致的肿瘤进展至今机制不明。通过前期临床组织标本的表达谱测序与耐药细胞的全基因组功能缺失筛选技术发现铁死亡通路抑制因子GPX4与肾癌依维莫司获得性耐药具有相关性；功能学实验证明GPX4可通过调控细胞内脂质过氧化抑制细胞铁死亡效应，进一步利用m6A甲基化测序等高通量测序技术发现铁死亡激动剂RSL3可通过抑制FTO介导的GPX4甲基化效应解除其对铁死亡通路的抑制，从而补救细胞获得性耐药的表型。因此我们提出科学假说：依维莫司的获得性耐药依赖GPX4，应用铁死亡诱导剂RSL3可通过FTO介导的m6A甲基化效应解除GPX4对铁死亡信号的抑制，从而启动了铁死亡程序，克服肿瘤细胞的耐药抵抗。本课题拟建立临床前模型通过一系列研究探讨在一线、二线治疗失败背景下细胞铁死亡效应对肿瘤生长及耐药的影响机制，为研究下一代晚期肾癌靶向药物提供理论依据。

Many patients with metastatic renal cell carcinoma benefit from everolimus, second line therapy. However, the mechanisms, of which recurrence and progression always happens after a first response, are unknown. By using Crispr-Cas9 mediated Genome wide loss-of-function screening, we found GPX4 as crucial suppressor of ferroptosis plays an important role in the resistance. Moreover, the RSL3, activator of ferroptosis, could be able to rescue the phenotype of resistance to everolimus. Our hypothesis is that the acquired resistance of first line and second line sequential therapy for renal cell carcinoma reply on the suppression of GPX4 to ferroptosis pathway, which is probably the one of the mechanisms of resistance. RSL3 treatment could overcome the resistance to tumor cells by releasing the suppression of GPX4 to ferroptosis. We plan to set up the preclinical model to study the ferroptosis on tumor survival and resistance on the background of first and second line treatment failure.