Effects of small interfering RNA inhibit Class Ⅰ phosphoinositide 3-kinase on human gastric cancer cells

作     者：Bao-Song Zhu Li-Yan Yu Kui Zhao Yong-You Wu Xiao-Li Cheng Yong Wu Feng-Yun Zhong Wei Gong Qiang Chen Chun-Gen Xing 

作者机构：Department of General SurgeryThe Second Affiliated HospitalSoochow University Department of GastroenterologyQianfoshan HospitalShandong University 

出 版 物：《World Journal of Gastroenterology》 (世界胃肠病学杂志（英文版）)

年 卷 期：2013年第19卷第11期

页      面：1760-1769页

核心收录：

学科分类：1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

基　　金：Supported by The Natural Science Foundation of China,No. 81172348 Suzhou High-Level Talents Project,2008-11 Suzhou Science and Technology Development Foundation,2010SYS201031 the Science,Education,and Health Foundation of Suzhou City,SWKQ0914 and SWKQ0916 

主　　题：Gastric cancer cells Class I phosphoinositide 3-kinase RNA interference Apoptosis Autophagy 

摘      要：AIM: To investigate the effects of small interfering RNA (siRNA)-mediated inhibition of Class?I?phosphoinositide 3-kinase (Class?I?PI3K) signal transduction on the proliferation, apoptosis, and autophagy of gastric cancer SGC7901 and MGC803 cells. METHODS: We constructed the recombinant replication adenovirus PI3K(I)-RNA interference (RNAi)-green fluorescent protein (GFP) and control adenovirus NC-RNAi-GFP, and infected it into human gastric cancer cells. MTT assay was used to determine the growth rate of the gastric cancer cells. Activation of autophagy was monitored with monodansylcadaverine (MDC) staining after adenovirus PI3K(I)-RNAi-GFP and control adenovirus NC-RNAi-GFP treatment. Immunofluorescence staining was used to detect the expression of microtubule-associated protein 1 light chain 3 (LC3). Mitochondrial membrane potential was measured using the fluorescent probe JC-1. The expression of autophagy was monitored with MDC, LC3 staining, and transmission electron microscopy. Western blotting was used to detect p53, Beclin-1, Bcl-2, and LC3 protein expression in the culture supernatant. RESULTS: The viability of gastric cancer cells was inhibited after siRNA targeting to the Class?I?PI3K blocked Class?I?PI3K signal pathway. MTT assays revealed that, after SGC7901 cancer cells were treated with adenovirus PI3K(I)-RNAi-GFP, the rate of inhibition reached 27.48% ± 2.71% at 24 h, 41.92% ± 2.02% at 48 h, and 50.85% ± 0.91% at 72 h. After MGC803 cancer cells were treated with adenovirus PI3K(I)-RNAi-GFP, the rate of inhibition reached 24.39% ± 0.93% at 24 h, 47.00% ± 0.87% at 48 h, and 70.30% ± 0.86% at 72 h (P 0.05 compared to control group). It was determined that when 50 MOI, the transfection efficiency was 95% ± 2.4%. Adenovirus PI3K(I)-RNAi-GFP (50 MOI) induced mitochondrial dysfunction and activated cell apoptosis in SGC7901 cells, and the results described here prove that RNAi of Class?I?PI3K induced apoptosis in SGC7901 cells. The results showed that a