南方医科大学学报2024，Vol.44Issue(5)：885-893,9.DOI:10.12122/j.issn.1673-4254.2024.05.10
FMRP通过激活RAS/MAPK信号通路抑制结直肠肿瘤细胞的铁死亡
High expression of fragile X mental retardation protein inhibits ferroptosis of colorectal tumor cells by activating the RAS/MAPK signaling pathway
摘要
Abstract
Objective To investigate the mechanism by which fragile X mental retardation protein(FMRP)regulates ferroptosis evasion in colorectal cancer(CRC)cells.Methods We examined FMRP expression levels in CRC cell lines using RT-qPCR and Western blotting and analyzed the biological functions and signaling pathways involved in FMRP-mediated regulation of CRC progression using the TCGA database.A lentiviral FMRP overexpression vector(Lv-FMRP)and 3 knockdown vectors(siFMRP-1,siFMRP-2,and siFMRP-3)were constructed,and their effects on proliferation of HCT116 cells were examined using CCK8 assay and plate clone formation assay;the changes in cell ferroptosis level was determined using MDA/ROS/GSH/Fe2+kits,mitochondrial membrane potential changes were detected using JC-1 fluorescence staining,and the expressions of proteins associated with ferroptosis and the RAS/MAPK signaling pathway were detected using Western blotting.The subcutaneous tumorigenic potential of the transfected cells was evaluated in nude mice.Results Compared with normal colonic mucosal epithelial NCM460 cells,the CRC cell lines had significantly higher FMRP expression level.Bioinformatics analysis suggested the involvement of FMRP in regulation of reactive oxygen,oxidative stress-induced cell death,mitochondrial respiration,and glutathione metabolism pathways.In the cell experiments,FMRP knockdown significantly inhibited proliferation of HCT116 cells,lowered cellular GSH content,increased MDA and ROS levels,Fe2+fluorescence intensity,and mitochondrial membrane potential,and decreased SLC7A11/GPX4 protein expressions and the phosphorylation levels of ERK,MEK,MAPK,and RAS proteins;FMRP overexpression resulted in the opposite changes in the cells.In the tumor-bearing nude mice,HCT116 cells with FMRP knockdown showed attenuated tumorigenic potential with lowered xenograft growth rate and reduced SLC7A11 expression in the xenograft.Conclusion The high expression of FMRP inhibits ferroptosis in CRC cells and promotes progression of CRC by activating the RAS/MAPK signaling pathway.关键词
FMRP/铁死亡/RAS/MAPK信号通路/结直肠肿瘤Key words
fragile X mental retardation protein/ferroptosis/RAS/MAPK signaling pathway/colorectal cancer引用本文复制引用
王南,石斌,马小兰,吴伟超,曹佳..FMRP通过激活RAS/MAPK信号通路抑制结直肠肿瘤细胞的铁死亡[J].南方医科大学学报,2024,44(5):885-893,9.基金项目
宁夏回族自治区重点研发计划项目(2022CMG03124) （2022CMG03124）
宁夏回族自治区重点研发(引才专项)项目(2021BEB04046) （引才专项）
宁夏回族自治区第六批自治区青年科技人才托举工程项目(NXKJTJ2021119) （NXKJTJ2021119）
