PGRMC1-dependent lipophagy promotes ferroptosis in paclitaxel-tolerant persister cancer cells

Journal of Experimental & Clinical Cancer Research

Ji Hyeon You¹  Jaewang Lee¹  Jong-Lyel Roh¹ 

[1] Department of Otorhinolaryngology-Head and Neck Surgery, CHA Bundang Medical Center, CHA University School of Medicine, 13496, Seongnam, Gyeonggi-do, Republic of Korea;

关键词: Progesterone receptor membrane component 1;    Ferroptosis;    Fatty acid oxidation;    Lipophagy;    Tubulin detyrosination;   

DOI  :  10.1186/s13046-021-02168-2

来源: Springer

【 摘 要 】

BackgroundProgesterone receptor membrane component 1 (PGRMC1) is a heme-binding protein inducing dimerization with cytochrome P450, which mediates chemoresistance. Increased PGRMC1 expression is found in multiple types of resistant cancers, but the role of PGRMC1 in the ferroptosis of cancer cells remains unrevealed. Therefore, we examined the role of PGRMC1 in promoting ferroptosis in paclitaxel-tolerant persister cancer cells (PCC).MethodsThe effects of ferroptosis inducers and PGRMC1 gene silencing/overexpression were tested on head and neck cancer (HNC) cell lines and mouse tumor xenograft models. The results were analyzed about cell viability, death, lipid ROS and iron production, mRNA/protein expression and interaction, and lipid assays.ResultsPCC had more free fatty acids, lipid droplets, and fatty acid oxidation (FAO) than their parental cells. PCC was highly sensitive to inhibitors of system xc− cystine/glutamate antiporter (xCT), such as erastin, sulfasalazine, and cyst(e)ine deprivation, but less sensitive to (1S,3R)-RSL3. PGRMC1 silencing in PCC reduced ferroptosis sensitivity by xCT inhibitors, and PGRMC1 overexpression in parental cells increased ferroptosis by xCT inhibitors. Lipid droplets were degraded along with autophagy induction and autophagosome formation by erastin treatment in PCC. Lipophagy was accompanied by increased tubulin detyrosination, which was increased by SIRT1 activation but decreased by SIRT1 inhibition. FAO and lipophagy were also promoted by the interaction between lipid droplets and mitochondria.ConclusionPGRMC1 expression increased FAO and ferroptosis sensitivity from in vivo mice experiments. Our data suggest that PGRMC1 promotes ferroptosis by xCT inhibition in PCC.

【 授权许可】

CC BY