目的 研究干扰分选连接蛋白10（sorting nexin 10，SNX10）表达对人正常肠上皮FHC、NCM460细胞增殖、谷氨酰胺代谢的影响及α-常春藤皂苷调控作用的分子机制。方法 利用转染技术构建稳定敲低SNX10的FHC、NCM460细胞，qRT-PCR和Western blotting检测敲低效率；CCK-8、克隆形成实验检测细胞增殖能力；MTT筛选α-常春藤皂苷实验浓度并检测其对SNX10表达的影响；检测细胞内还原型谷胱甘肽含量；Western blotting检测细胞SNX10、哺乳动物雷帕霉素靶蛋白复合物1（mammalian target of rapamycin complex 1，mTORC1）/c-myc信号通路相关蛋白及下游谷氨酰胺转运蛋白SLC7A5表达情况。结果 敲低SNX10后FHC、NCM460细胞增殖异常加快（P＜0.01），细胞内还原型谷胱甘肽含量异常升高（P＜0.01），mTORC1/c-myc通路被激活，下游SLC7A5表达升高；而α-常春藤皂苷干预SNX10敲低细胞系后，细胞SNX10表达升高（P＜0.05、0.01），且上述变化发生逆转并渐趋空载细胞水平。结论 SNX10有望成为结直肠癌临床诊断及防治的新靶点，α-常春藤皂苷可逆转肠上皮细胞因SNX10敲低导致的快速增殖、mTORC1/c-myc信号通路活化及谷氨酰胺代谢的异常升高，从而抑制正常肠上皮细胞的恶性转化。

Objective To investigate the effects of interfering sorting nexin 10 (SNX10) expression on proliferation and glutamine metabolism of human normal intestinal epithelial cells FHC and NCM460 and molecular mechanism of regulation effect of α-hederin. Methods FHC and NCM460 cells with SNX10 stably knockdown were constructed using transfection approach. qRT-PCR and Western blotting were used to detect knockdown efficiency. CCK-8 and clone formation assays were used to detect cell proliferation ability. MTT method was used to screen the experimental concentrations of α-hederin and detect its effects on SNX10 expression. The intracellular content of GSH was detected. The expressions of SNX10, mammalian target of rapamycin complex 1 (mTORC1)/c-myc signaling pathway-related proteins and downstream glutamine transporter protein SLC7A5 were detected by Western blotting. ResultsThe proliferation of FHC and NCM460 cells was abnormally accelerated after SNX10 knockdown (P＜0.01), intracellular glutathione content was abnormally increased (P＜0.01), mTORC1/c-myc pathway was activated, and expression of downstream SLC7A5 was elevated, whereas after α-hederin intervention in SNX10 knockdown cell lines, both SNX10 gene and protein expression levels were increased (P＜0.05, 0.01) and the above changes were reversed and gradually tended to the empty vector group.Conclusion SNX10 is expected to be a new target for clinical diagnosis and prevention of colorectal cancer. α-Hederin can reverse the rapid proliferation, activation of the mTORC1/c-myc signaling pathway and abnormal increase of glutamine metabolism of intestinal epithelial cells due to SNX10 knockdown, thus inhibiting the malignant transformation of normal intestinal epithelial cells.

R285.5

国家自然科学基金面上项目（81973523）；江苏省研究生培养创新工程研究生科研与实践创新计划项目（SJCX22_0746）