调控RB1CC1和LZTFL1促肝癌细胞铁死亡机制研究

Ferroptosis is one type of programmed cell death resulted from changes of metabolism. Compared to apoptosis, ferroptosis is rarely studied in liver cancer cells. Stimulation of ferroptosis has been proved to have great potential to treat liver cancer; however, the molecular mechanism underlying how to trigger ferroptosis in liver cancer cells still remains unclear. By high-throughput methods, we previously uncovered that during pro-ferroptosis process, the mRNA and protein expression levels of RB1CC1 and LZTFL1 are simultaneously changed, and both RB1CC1 and LZTFL1 stimulate ferroptosis whereas inhibit transformative phenotypes of liver cancer cells. Thereby, we hypothesize that RB1CC1 and LZTFL1 act as signal mediators, controlled by pro-ferroptosis factors, to stimulate ferroptosis and inhibit liver tumorigenesis via changing metabolism. This project will provide more evidences that RB1CC1 and LZTFL1 are molecules whose expression are significantly changed resulted from stimulation of ferroptosis, and further reveal the importance of RB1CC1 and LZTFL1 for their roles in stimulation of ferroptosis and inhibition of tumorigenesis. Also, we will focus on metabolic changes to uncover possible molecular mechanism underlying how RB1CC1 and LZTFL1 boost ferroptosis. Simultaneously, we plan to reveal regulatory rules of controlling expression of RB1CC1 and LZTFL1 during ferroptosis, the effects on ferroptosis and metabolism caused by key transcription factors, and the clinical significance of ferroptosis and its related molecules in liver cancer to a certain extent. Taken together, we will provide evidences that ferroptosis can be regarded as a therapeutic target for treating liver cancer.

铁死亡是由代谢改变造成的一种程序性死亡，相对凋亡，肝癌细胞内铁死亡的研究很少。诱导铁死亡治疗肝癌已证明具有较大潜力，但促肝癌细胞发生铁死亡的分子机制尚不清。我们前期利用高通量方法发现肝癌细胞促铁死亡过程中，RB1CC1和LZTFL1的mRNA和蛋白表达水平同时改变，两分子均可促铁死亡并抑肝癌，故猜测：RB1CC1和LZTFL1可作为信号传递者，受控于促铁死亡因素，并可通过改变代谢促铁死亡并抑肝癌。本项目将提供更多证据证明RB1CC1和LZTFL1为肝癌细胞诱发铁死亡过程中表达发生明显改变的分子，确定两者在促铁死亡及抑肝癌过程中的重要性。此外，从代谢改变的角度阐明RB1CC1和LZTFL1促铁死亡的分子机制。同时解析促铁死亡过程中调控RB1CC1和LZTFL1表达的规律，明确相关重要转录因子对铁死亡及代谢的影响，并一定程度探索铁死亡及相关分子在肝癌中的临床意义，为铁死亡治疗肝癌提供依据。

铁死亡是是一种新型程序性死亡，主要依赖于质膜脂质过氧化所致的细胞及细胞器通透性增加。因肿瘤细胞较正常细胞对铁死亡诱导更为敏感，导致铁死亡诱导成为一种新型安全的临床前肿瘤治疗方法。为解析铁死亡触发及发展机制，了解其调控网络尤为重要，但肿瘤细胞内铁死亡方式尚不清。本项目目的为寻找调控铁死亡因素，进一步阐明铁死亡抑肿瘤相关机制。在本项目资助下，本项目明确了：1）肝癌细胞铁死亡关键分子RB1CC1等，为铁死亡治疗肝癌提供理论依据；2）肝癌细胞中铁死亡转录调控及蛋白酶体参与的调控机制，可进一步解析铁死亡信号传导网络；3）胱氨酸、谷氨酰胺、谷胱甘肽以及铁代谢对铁死亡调控重要性；4）关键指标在肿瘤中判断铁死亡敏感性的临床意义，为临床转化提供依据。在此基础上，项目负责人以通讯作者发表论文11篇，包括Mater Today Bio（共同通讯，IF: 10.761）、Cancer Commun（最后通讯，IF: 15.283）、J Exp Clin Cancer Res（最后通讯，IF: 12.658）、Clin Transl Med（最后通讯，IF: 8.554）、Cell Death Dis（最后通讯，IF: 9.685）、Free Radic Biol Med（最后通讯，IF: 8.101）、Theranostics（最后通讯，IF: 11.600）、Redox Biol（最后通讯，2019, 2021, IF: 10.787）等。参加的16次学术交流，一定程度提升了项目负责人学术影响力。以第一发明人获得授权专利3项，其中一项已转化250万。另已申请7项发明专利，目前均处于已受理状态。此外，资助期间项目负责人共招收硕士5名，博士4名，2名硕士已成功转博，1名硕士获上海市优秀毕业生称号，已一定规模建立肿瘤基础及肿瘤临床检验研究团队，因此已完成本项目所有指标。