补体C1q在胶质母细胞瘤替莫唑胺耐药中的作用及机制研究

Role and Mechanism of Complement C1q in Temozolomide Resistance in Glioblastoma

目的:探究补体C1q在胶质母细胞瘤(glioblastoma multiforme,GBM)替莫唑胺(TMZ)耐药中的作用及机制研究。方法:公共数据库挖掘补体C1q相关基因(C1QA、B和C)在GBM中的表达模式,实时荧光定量PCR(RTqPCR)检测C1QA、B和C的表达水平。CCK8法测定U251和U251耐药株(U251/TR)细胞活力和半数抑制浓度(IC_(50)),流式细胞术检测U251和U251/TR细胞凋亡。Transwell法检测U251/TR细胞迁移能力,Western Blot法检测补体C1q A链(C1QA),O^(6)-甲基鸟嘌呤-DNA甲基转移酶(MGMT)的蛋白表达水平。结果:生物信息学分析显示C1QA、B和C在GBM中表达升高,且C1QA和B与肿瘤分级相关。RT-qPCR和Western Blot证实C1QA在U251/TR中表达下降,且在U251/TR中过表达C1QA可以下调IC_(50),并增加了TMZ诱导的细胞凋亡和细胞迁移抑制,以及下调MGMT的蛋白水平。结论:GBM对TMZ耐药后C1QA水平下降,过表达C1QA可以逆转部分GBM的耐药性。

Objective:To investigate the role and mechanism of complement C1q in temozolomide(TMZ)resistance in glioblastoma multiforme(GBM).Methods:The expression patterns of complement C1q-related genes(C1QA,B and C)in GBM were mined by public database,and the expression levels of C1QA,B and C were detected by real-time fluorescence quantitative PCR(RT-qPCR).CCK8 method was used to determine the cell viability and half inhibitory concentration(IC_(50))of U251 and U251 drug-resistant strains(U251/TR),and flow cytometry was used to detect the apoptosis of U251 and U251/TR cells.Transwell assay was used to detect the migration ability of U251/TR cells.Western blot was used to detect the protein expression levels of complement C1 q A chain(C1QA)and O^(6)-methylguanine-DNA methyltransferase(MGMT).Results:Bioinformatics analysis showed that C1QA,B and C were up-regulated in GBM,and C1QA and B were associated with tumor grade.RT-qPCR and Western blot confirmed that the expression of C1QA was decreased in U251/TR,and overexpression of C1QA in U251/TR could downregulate IC_(50),increase TMZ-induced apoptosis and cell migration inhibition,and down-regulate MGMT protein levels.Conclusion:The level of C1QA in GBM decreased after TMZ resistance,and overexpression of C1QA can reverse the resistance of some GBM.