论文部分内容阅读
本研究探讨去泛素化酶UCHL1通过影响肿瘤细胞主动外排药物和乳腺癌肿瘤干细胞(breast cancer stem cell,BCSC)调控乳腺癌化疗耐药的作用及机制。比较肿瘤细胞MCF-7及其阿霉素耐药株MCF-7/ADM的UCHL1表达差异,以抑制剂LDN57444干预MCF-7/ADM的UCHL1功能,检测MCF-7/ADM的半数抑制浓度,流式细胞术检测ADM在细胞内的积聚和CD44+CD24-BCSC比例,微球体形成实验观察BCSC干性,real-time PCR和western blotting检测药泵蛋白和干细胞相关基因的表达。结果显示,MCF-7/ADM高表达UCHL1,抑制UCHL1后MCF-7/ADM的半数抑制浓度显著下降,药泵蛋白P-gp和MRP1表达下调且药物在细胞内的聚积增加,MCF-7/ADM中CD44+CD24-BCSC比例、微球体形成能力及干细胞相关基因表达均显著下降。以上结果说明UCHL1可促进乳腺癌细胞耐药性形成,主要通过改变药泵蛋白介导的经典耐药机制实现,并与促进BCSC干性密切相关。
This study was aimed to investigate the role and mechanism of deubiquitination enzyme UCHL1 in modulating chemoresistance in breast cancer by affecting the active efflux of tumor cells and breast cancer stem cells (BCSC). The difference of UCHL1 expression in MCF-7 / ADM cells between MCF-7 / ADM and MCF-7 / ADM cells was analyzed. The inhibitory effect of LDN57444 on the function of UCHL1 in MCF-7 / The accumulation of ADM in the cells and the proportion of CD44 + CD24-BCSCs were detected by cytometry. The expression of drug-pump proteins and stem cell-related genes were detected by real-time PCR and western blotting. The results showed that MCF-7 / ADM overexpressing UCHL1 significantly inhibited the half-inhibitory concentration of MCF-7 / ADM after inhibiting UCHL1, down-regulated the expression of P-gp and MRP1, and increased the intracellular accumulation of MCF- The proportion of CD44 + CD24-BCSCs, the ability of microspheres formation and the expression of stem cell related genes in ADM decreased significantly. These results indicate that UCHL1 can promote the formation of drug resistance in breast cancer cells mainly through the change of drug-pump-mediated classical drug resistance mechanism and is closely related to the promotion of BCSC dryness.