E6AP通过调节糖酵解促进胃癌细胞增殖和迁移的机制研究

Mechanism of E6AP in promoting gastric cancer cell proliferation and migration by regulating glycolysis

背景肿瘤细胞的快速增殖和远处转移是胃癌患者的主要死因,探索胃癌发生发展机制、寻找新的诊断及治疗靶点具有重要意义。目的探讨E3泛素连接酶E6相关蛋白(E3 ubiquitin ligase E6-associated protein,E6AP)对胃癌细胞增殖、迁移以及有氧糖酵解能力的影响。方法免疫组化检测胃癌组织和癌旁组织中E6AP的表达情况;分析E6AP的表达与胃癌患者预后的关系;Western blot检测E6AP在胃癌细胞系及胃正常黏膜上皮细胞系中的表达情况;检测HK2、ENO1等糖酵解相关蛋白在胃癌细胞中的表达情况;采用5-Ethynyl-2’-deoxyuridine(EdU)实验和Transwell实验分别检测E6AP对胃癌细胞增殖和迁移能力的影响;用糖酵解相关检测指标反映胃癌细胞有氧糖酵解能力。结果E6AP在胃癌组织中的表达高于在癌旁组织中的表达(P<0.05)。Western blot及糖酵解相关实验结果显示,与NC-E6AP组比较,sh-E6AP组胃癌细胞乳酸水平、丙酮酸水平、ATP水平及葡萄糖摄取率均降低(P<0.05)。EdU和Transwell实验结果显示,sh-E6AP组细胞增殖和迁移能力低于NC-E6AP组细胞(P<0.05)。结论E6AP在胃癌组织中高表达。E6AP通过增强胃癌细胞有氧糖酵解水平提升其增殖和迁移能力。E6AP或可成为预测胃癌患者预后的新型分子标志物和治疗靶点。

Background Rapid proliferation of cancer cells and distant metastasis are the main causes of death in gastric cancer patients.Exploring the mechanism of gastric cancer development and finding novel diagnostic and therapeutic targets are the urgent problems to be solved nowadays.Objective To investigate the effects of E3 ubiquitin ligase E6-associated protein(E6AP)on the proliferation,migration,and aerobic glycolytic capacity of gastric cancer cells.Methods Immunohistochemistry was used to detect the expression of E6AP in gastric cancer tissues and paracancerous tissues.The relationship between the expression of E6AP and the prognosis of gastric cancer patients was analyzed,the expression of E6AP in gastric cancer cell lines and normal gastric mucosal epithelial cell lines was detected by Western blot,and the expression of HK2,ENO1 and other glycolysis-related proteins in gastric cancer cells was detected.The proliferation and migration abilities of cells were examined by the 5-Ethynyl-2'-deoxyuridine(EdU)assay and Transwell assay,respectively;and the aerobic glycolysis ability of gastric cancer cells was reflected by the glycolysisrelated assays.Results The expression of E6AP in gastric cancer tissues was significantly higher than its expression in paracancerous tissues(P<0.05).Western blot and glycolysis-related assays showed that lactate level,pyruvate level,ATP level,and glucose uptake rate of gastric cancer cells in the sh-E6AP group were significantly lower compared with that of NC-E6AP(P<0.05).EdU and Transwell assays showed that the proliferation and migration ability of cells in sh-E6AP group was significantly lower than that of cells in NC-E6AP group(P<0.05).Conclusion E6AP is highly expressed in gastric cancer tissues,and it enhances the proliferation and migration of gastric cancer cells by increasing their aerobic glycolysis level.E6AP may be a novel molecular marker and therapeutic target to predict the prognosis of gastric cancer patients.