肾透明细胞癌细胞系中NOTCH1调控PTEN／PI3K／AKT信号通路促进肿瘤进展

目的：研究NOTCH1在肾透明细胞癌细胞系中的生物功能及其对PTEN／P13K／AKT信号通路的调控。方法：在肾透明细胞癌细胞系Caki-2及人肾小管上皮细胞系HKC中沉默NOTCH1，检测其对细胞增殖，细胞周期，凋亡以及肿瘤细胞侵袭和迁徙能力的影响。Western—blot和qrtPCR检测HESl，PTEN，AKT、（p-S473）蛋白及mRNA的变化。结果：在两株细胞中，沉默NOTCH1均能抑制细胞生长，促进细胞周期阻滞，抑制肿瘤细胞的侵袭和迁徙。沉默NOTCHl引起HESl与AKT（p-s473）蛋白下降，PTEN的蛋白及mRNA水平明显升高。沉默HES1引起PTEN蛋白及mRNA升高。结论：在肾透明细胞癌细胞系中，过度活化的NOTCHl通过调节PTEN/PI3K/AKT信号通路起促癌作用，这为肾透明细胞癌的治疗提供了新的治疗策略。

NOTCH1 promotes the pathogenesis of clear-cell renal-cell carcinoma by regulating the pathway of PTEN/PI3K/AKT in vitro

Objective：Although NOTCH1 plays a wide ranging role in controlling cell fate, differentiation and development, the pathological roles of NOTCH1 in clear-cell renal cell carcinoma（CCRCC） are still unclear. In this study, the biological function of NOTCH1 was examined and the interaction of NOTCH1 with the phosphatase and tensin homologue deleted on chromosome 10 （PTEN）/phosphatidylinositol 3 kinase （PI3K）/AKT path way was investigated in vitro. Methyl： The effects of NOTCH1 signaling pathway on cells proliferation, apoptosis, invasion and migration were detected by MTS assay, flow cytometry analyses and transwell chamber assay respec tively. In addition, the alteration of NOTCH1, HES1, PTEN, AKT（phosphorylation at Ser473）in CCRCC cell line（Caki 2） and human normal kidney tubule epithelial cell line （HKC） were analyzed by Western blot and qrt- PCR, before and after transfected with siRNA against NOTCH1. Result： NOTCH1 signaling cascade was constitutively active in human CCRCC cell lines. Blocking NOTCH1 signaling resulted in the attenuation of prolifera- tion, invasion and migration, as well as PTEN up-regulation with decreased AKT phosphorylation. Conclusion： Our findings indicated that the expression of NOTCH1 receptors was upregulated and NOTCH1 could regulates PTEN expression and the activity of the PI3K/AKT pathway via HES1 in CCRCC. This might provide the basis for the design of new therapeutic strategies for CCRCC.