G蛋白信号调节体-G alpha相互作用蛋白C端2通过上调SNIAL1表达及促进胃癌细胞增殖、侵袭与迁移

Regulator of G protein signaling-G alpha interacting protein COOH 2 promotes proliferation,invasion and migration of gastric cancer cells by up-regulating the expression of SNIAL1

目的利用胃癌细胞株、患者胃癌组织及基因表达谱(GEPIA)数据库中相关数据确定G蛋白信号调节体-G alpha相互作用蛋白C端2(GIPC2)蛋白在胃癌中的表达量,探讨其在体外对胃癌细胞增殖及迁移的作用.方法将GIPC2的短发卡RNA(shRNA)以及过表达质粒分别转染GIPC2高表达及低表达的细胞株BCG803及AGS中,利用细胞增殖和迁移实验探讨GIPC2在胃癌细胞株中的作用,同时探讨GIPC2对化疗药物敏感性的影响.两组间比较采用t检验,两组以上的比较采用单因素方差分析.使用Spearman秩相关检验验证GIPC2与SNAIL1的表达是否存在线性相关.结果GIPC2在胃癌细胞株及胃癌患者组织中(相对表达量胃癌组织比正常对照:2.844±1.201比1.601±0.612,P<0.05)高表达,GIPC2可以促进胃癌细胞的增殖和迁移,并使细胞周期相关蛋白(Cyclin D1)、增殖细胞核抗原(PCNA)及转移相关蛋白E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、波形蛋白(Vimentin)、基质金属蛋白酶(MMP)-2、MMP-9表达增加.其中划痕实验显示,敲低组迁移率明显低于对照组(0.812±0.012、0.525±0.016,P<0.05);迁移侵袭实验显示,高表达组细胞迁移率和侵袭率分别是对照组的4.5、3.9倍(P<0.05);同时,GIPC2能够降低肿瘤细胞对化疗药物的敏感性,使细胞中化疗药物敏感性相关基因CD133、CD44和性别决定区相关高迁移率族盒蛋白-2(SOX-2)表达均增加.机制上,在上皮-间充质转化(EMT)中发挥重要作用的转录因子SNAIL1蛋白在表达上与GIPC2呈正相关(r=0.435,P<0.05);敲低组SNAIL1蛋白表达量(0.121±0.011)明显低于对照组SNAIL1蛋白表达量(1.032±0.011,P<0.05);过表达组mRNA水平(3.351±0.121)明显高于对照组mRNA水平(1.021±0.031,P<0.05).结论GIPC2具有促进胃癌细胞增殖和迁移的作用,这一作用主要是通过SNAIL1蛋白来实现的.

Objective Confirm the expression of regulator of G protein signaling-G alpha interacting protein COOH 2(GIPC2)in gastric carcinoma cell lines and patient samples compared to that in normal controls and detect the role of GIPC2 in gastric carcinoma development.Methods shGIPC2 and GIPC2 plasmid are transfected into AGS and BCG803 cell line,respectively.Transfected cells are used for cell proliferation and invasion assay as well as for testing sensitivity to chemotherapeutic agents.Results GIPC2 was highly expressed in gastric cancer cell lines and gastric cancer patients(relative expression of gastric cancer tissue vs.normal control:2.849±1.201 vs.1.603±0.605,P<0.05).GIPC2 can promote the proliferation and migration of gastric cancer cells,and increase the expression of cell cycle related proteins Cyclin D1,proliferating cell nuclear antigen(PCNA)and metastasis-associated proteins E-cadherin,N-cadherin,Vimentin,matrix metalloproteinase(MMP)-2 and MMP-9.The scratch test showed that the mobility of the knockdown group was significantly lower than that of the control group(0.812±0.012,0.525±0.016).The migration and invasion experiments showed that the cell migration rate and invasion rate of the high expression group were about 4.5 times of the control group,respectively.Times,and statistically significant.At the same time,GIPC2 can reduce the sensitivity of tumor cells to chemotherapeutic drugs,and increase the expression of chemotherapeutic drug-related genes CD133,CD44 and sex determination region related high mobility group box protein-2(SOX-2)in cells.In terms of mechanism,the expression of SNAIL1 protein in epithelial-mesenchymal transition(EMT)was positively correlated with GIPC2(r=0.435,P<0.05);the expression of SNAIL1 protein in knockdown group(0.121±0.011)was significantly lower than that of control group SNAIL1 protein.The expression level(1.032±0.011)was statistically significant.The mRNA level of the overexpression group(3.351±0.121)was significantly higher than that of the control group(1.021±0.031)(P<0.05).Conclusion GIPC2 acts as an oncogenic role in gastric carcinoma in vitro and it probably exerts this role through regulating SNAIL1.