科罗索酸通过FOXF1诱导非经典自噬途径促进肝癌细胞铁死亡的机制研究

The applicant has been long engaged in the study of active constituents of the traditional used anti-tumor TCM, Mao Ren Sheng, and firstly found the role of corosolic acid in promoting apoptosis of cancer cells, and reported that the anti-cancer effect of corosolic acid was associated with the activity of oncoprotein YAP. In the previous studies, applicant found that corosolic acid caused programmed cell death in liver cancer cells mainly through a new type of cell death pattern, ferroptosis, in which through induction of the non-canonical autophagy. We identified that FOXF1 was up-regulated in corosolic acid-induced ferroptosis through high-throughput sequencing combined with bioinformatics analysis. Moreover, FOXF1 was indispensable in the process of corosolic acid-induced ferroptosis. Thus, we hypothesized that corosolic acid promotes liver cancer cell ferroptosis by induction of non-canonical autophagy through FOXF1. Cell biology, molecular biology, high-throughput sequencing and metabonomical technics will be introduced. We expect to analyze the mechanism of how corosolic acid induced ferroptosis from multiple perspectives. For example, corosolic acid might induce non-canonical pathway autophagy and alter metabolism through FOXF1 in liver cancer cell. This research will provide new laboratorial supports for corosolic acid in the treatment of liver cancer.

申请人在探索常用抗肿瘤中药——猫人参的抗肿瘤活性成分研究中，首次发现科罗索酸促癌细胞凋亡活性，在进一步的科罗索酸抗肿瘤作用机制研究中，报道了其抗肝癌作用与癌蛋白YAP活性相关。在后续研究中，申请人发现科罗索酸也可通过新型细胞死亡模式——铁死亡使肝癌细胞发生程序性死亡，并且此方式与科罗索酸诱导非经典细胞自噬途径相关。申请者通过高通量组学联合生物信息学分析筛选到FOXF1可能在科罗索酸促铁死亡过程中表达升高。同时，我们还发现FOXF1对科罗索酸促铁死亡作用是不可或缺的。据此，我们提出本课题假说：科罗索酸可通过FOXF1促进肝癌细胞依赖非经典细胞自噬途径诱导铁死亡。本课题拟通过细胞生物学、分子生物学、高通量组学及代谢组学等技术，从科罗索酸通过FOXF1诱导肝癌细胞发生非经典途径自噬及改变肝癌细胞代谢等多角度深入解析科罗索酸促肝癌细胞铁死亡机制，为科罗索酸可作为治疗肝癌的潜在药物提供实验室依据。

原发性肝癌是世界上第三大癌症死因，缺乏有效的治疗手段是其高死亡率的主要原因。已证明科罗索酸（CA）具有抗肿瘤活性。在这项研究中，我们发现CA可以增加肝癌细胞铁死亡的敏感性，铁死亡是一种受调节的细胞死亡形式，其特征是铁依赖性脂质过氧化物的积累达到致命水平。进一步的机制研究发现CA通过HERPUD1抑制谷胱甘肽（GSH）的合成，降低细胞GSH水平来增加肝癌细胞铁死亡的敏感性。进一步的研究发现科罗索酸通过HERPUD1作用于GSS相关的E3泛素连接酶MDM2来增加GSS的泛素化而降低GSS的含量，进而抑制GSH的合成增加肝癌细胞铁死亡的敏感性。重要的是，小鼠异种移植模型也证明了CA通过HERPUD1抑制肿瘤生长。总的来说，我们的研究发现表明CA是开发抗肝癌治疗的候选成分。