BCAT1在食管鳞癌发生发展中的机制研究  

Study on the mechanism of BCAT1 in the occurrence and development of esophageal squamous cell carcinoma

作　　者：赵华莹[1] 李晟磊[1] ZHAO Huaying;LI Shenglei(Department of Pathology,the First Affiliated Hospital of Zhengzhou University,Zhengzhou 450052,China)

机构地区：[1]郑州大学第一附属医院病理科,河南郑州450052

出　　处：《胃肠病学和肝病学杂志》2025年第3期318-325,共8页Chinese Journal of Gastroenterology and Hepatology

基　　金：国家自然科学基金面上项目(82273324)。

摘　　要：目的探讨BCAT1在食管鳞癌(esophageal squamous cell carcinoma,ESCC)发生发展中的相关分子机制。方法质谱分析鉴定BCAT1的互作蛋白PKM2,Co-IP检测其两者存在的相互作用和分子机制。结果质谱结合Co-IP实验证明BCAT1与PKM2存在相互作用。Western blotting结果显示,与Control组和BCAT1-siRNA组相比,BCAT1-siRNA联合MG132组的PKM2蛋白表达水平呈现明显增高的趋势;BCAT1过表达组中采用CHX处理的细胞中PKM2的蛋白半衰期显著短于空载体组。免疫共定位结果表明BCAT1和PKM2共定位于ESCC细胞胞质。Co-IP实验结果表明,E3泛素连接酶Parkin与PKM2存在互作。Western blotting结果表明,与Control组相比,Parkin siRNA组中PKM2蛋白表达增加;与NC组相比,Parkin-OE组中PKM2的表达降低。泛素实验结果表明Parkin过表达增加了PKM2的降解水平。此外,与Parkin-OE组相比,Parkin-OE联合MG132组的PKM2蛋白表达水平显著增高。结论ESCC细胞中BCAT1与PKM2存在互作,BCAT1依赖于泛素-蛋白酶体途径调控ESCC细胞中PKM2的表达水平。ESCC细胞中Parkin与PKM2的互作导致PKM2的降解,进而抑制ESCC的进展。Objective To investigate the molecular mechanism of BCAT1 in the occurrence and development of esophageal squamous cell carcinoma(ESCC).Methods The interaction protein PKM2 of BCAT1 was identified by mass spectrometry,and the interaction and molecular mechanism of the two proteins were detected by Co-IP.Results The interaction between BCAT1 and PKM2 was proved by mass spectrometry and Co-IP experiment.Western blotting results showed that compared with Control group and BCAT1-siRNA group,the PKM2 protein expression level of BCAT1-siRNA combined with MG132 group showed a significantly increased trend.The half-life of PKM2 protein in CHX-treated cells with BCAT1 overexpression was significantly shorter than that in empty carrier group.Immunocolocalization results showed that BCAT1 and PKM2 were co-localized in the cytoplasm of ESCC cells.The Co-IP experiment results showed that the E3 ubiquitin ligase Parkin interacts with PKM2.Western blotting results showed that PKM2 protein expression increased in Parkin siRNA group compared with Control group.The expression of PKM2 in Parkin-OE group was decreased compared with NC group.The results of ubiquitin experiment showed that the overexpression of Parkin increased the degradation of PKM2.In addition,compared with Parkin-OE group,PKM2 protein expression in Parkin-OE combined with MG132 group was significantly increased.Conclusion BCAT1 interacts with PKM2 in ESCC cells,and BCAT1 regulates PKM2 expression in ESCC cells by ubiquitin-proteasome pathway.The interaction between Parkin and PKM2 in ESCC cells leads to the degradation of PKM2,which inhibits the progression of ESCC.

关 键 词：食管鳞癌 支链氨基酸转移酶1 糖酵解 泛素化 

分 类 号：R735.1[医药卫生—肿瘤]