假基因FMO6P抑制胃癌侵袭转移作用及其机制探索

Role and possible mechanism of pseudogene FMO6P in inhibiting invasion and metastasis of gastric cancer

目的:探究胃癌中假基因FMO6P表达、临床意义及其调控胃癌细胞转移潜能的作用和分子机制。方法:通过实时定量反转录聚合酶链式反应(qRT-PCR)检测胃癌组织和细胞株FMO6P表达水平。构建过表达及敲低FMO6P胃癌细胞株,通过transwell实验检测细胞的侵袭和迁移能力。在裸鼠皮下或腹腔中接种FMO6P过表达胃癌细胞,检测其体内增殖和转移潜能改变。使用Western blot实验检测胃癌细胞敲低或过表达FMO6P后E-钙黏着蛋白、N-钙黏着蛋白、ZEB1、MMP2等上皮-间质转化(EMT)标志物的表达水平和AKT/mTOR通路的活化水平。结果:FMO6P在胃癌组织中表达显著降低,并与肿瘤大小、TNM分期显著相关。过表达FMO6P抑制胃癌细胞的侵袭和迁移能力,并显著降低胃癌细胞在裸鼠体内的皮下成瘤能力和腹腔种植能力。下调FMO6P促进胃癌细胞的侵袭和迁移能力,过表达FMO6P促进胃癌细胞中E-钙黏着蛋白的表达,降低N-钙黏着蛋白、ZEB1和MMP2的水平,并抑制AKT/mTOR信号通路的活化。结论:假基因FMO6P可能通过阻断AKT/mTOR信号抑制胃癌细胞的体内、外侵袭转移潜能。

Objective To determine the expression and clinical significance of pseudogene FMO6P in gastric cancer,and explore its functions and underlying molecular mechanism in regulating the invasion and metastasis of gastric cancer cells.Methods The expression level of FMO6P in gastric cancer tissues and cell lines was detected by quantitative real time polymerase chain reaction(qRT‑PCR).The migration and invasion abilities of gastric cancer cells were detected by transwell assay.The effect of FMO6P on the tumor formation and peritoneal dissemination of gastric cancer cells were evaluated by injecting FMO6P‑overexpressing gastric cancer cells into the subcutaneous or peritoneal cavity of nude mice respectively.The expression levels of epithelial‑mesenchymal transition(EMT)markers,including E‑cadherin,N‑cadherin,ZEB1,MMP2,and the activation of AKT/mTOR pathway in FMO6P‑overexpressing or knockdown gastric cancer cells were measured by Western blot.Results The expression of FMO6P was significantly reduced in tumor tissues compared to its adjacent non‑tumor tissues of gastric cancer,FMO6P expression level in tumor tissues was correlated with tumor size and TNM stage.Overexpression of FMO6P significantly inhibited the invasion and migration abilities of gastric cancer cells,while downregulation of FMO6P expression promoted the invasion and migration ability of gastric cancer cells.Overexpression of FMO6P in gastric cancer cells significantly inhibited the subcutaneous tumor formation and peritoneal dissemination of gastric cancer cells in nude mice.Moreover,overexpression of FMO6P promoted the expression of Ecadherin,and inhibited the expression of N‑cadherin,ZEB1,and MMP2 in gastric cancer cells.The phosphorylation levels of AKT and mTOR were also downregulated in gastric cancer cells overexpressing FMO6P.Conclusions All these findings suggested that pseudogene FMO6P suppresses the invasion and migration potential of gastric cancer cells in vitro and in vivo,which is possibly through the inhibition of the AKT/mTOR signaling pathway.