COPB2表达对胃癌细胞增殖、迁移和侵袭的影响

Effect of COPB2 expression on proliferation,migration,and invasion of gastric cancer cells

背景外被体蛋白复合物β2亚基(coatomer protein complex subunit beta 2,COPB2)可参与调节多种肿瘤细胞的恶性生物学行为,而其在胃癌中表达和临床意义仍不完全明确.目的探究COPB2对胃癌细胞增殖、侵袭和迁移能力的影响及其机制.方法采用免疫组化法观察COPB2在胃癌组织和癌旁组织中的表达情况.采用Western blot检测胃癌组织和胃癌细胞系(SGC-7901、MKN45和AGS)中COPB2蛋白的表达情况.将COPB2-shRNA及其相应的阴性对照(Con-shRNA)、pcDNA-COPB2及其相应的阴性对照(pcDNA-Con)转染到SGC-7901细胞后,采用CCK-8法、细胞集落形成法和Transwell法分析敲低或过表达COPB2对胃癌细胞增殖、集落形成、迁移和侵袭能力的影响;采用Western blot检测敲低或过表达COPB2对胃癌细胞中Akt信号的影响.建立肿瘤异体移植模型,检测敲低COPB2对瘤体生长能力的影响.结果相对于癌旁组织和正常人胃上皮细胞GES-1,胃癌组织和胃癌细胞系(SGC-7901、MKN45和AGS)中COPB2蛋白表达均显著升高.敲低COPB2能抑制SGC-7901增殖、集落形成、迁移与侵袭的能力和p-Akt的蛋白表达,而过表达COPB2则呈现相反作用.另外,肿瘤异体移植模型实验证实敲低COPB2能抑制SGC-7901细胞在体内的生长.结论敲低COPB2表达可抑制胃癌细胞增殖、侵袭转移,且这一作用可能与其抑制Akt信号活性相关.

BACKGROUND Coatomer protein complex subunit beta 2(COPB2)is involved in the regulation of malignant biological behavior of various tumor cells.However,its expression and clinical significance in gastric cancer are still unclear.AIM To investigate the effects of COPB2 on the proliferation,invasion,and migration of gastric cancer cells and the possible mechanism.METHODS Immunohistochemical method was used to observe the expression of COPB2 in gastric cancer and adjacent tissues.Western blot was used to detect the expression of COPB2 protein in gastric cancer tissues and gastric cancer cell lines(SGC-7901,MKN45,and AGS).After transfection of COPB2-shRNA and its corresponding negative control(Con-shRNA),and pcDNA-COPB2 and its corresponding negative control(pcDNA-Con)into SGC-7901 cells,the effects of knockdown or overexpression of COPB2 on the proliferation,colony formation,migration,and invasion ability of gastric cancer cells were analyzed by CCK-8 assay,cell colony formation assay,and Transwell assay,and the effect of knockdown or overexpression of COPB2 on AKT signaling in gastric cancer cells was detected by Western blot.A tumor xenograft model was established to detect the effect of knockdown of COPB2 on tumor growth.RESULTS Compared with adjacent tissues and normal gastric epithelial cells(GES-1),the expression of COPB2 protein was significantly increased in gastric cancer tissues and gastric cancer cell lines(SGC-7901,MKN45,and AGS).Knockdown of COPB2 inhibited the proliferation,colony formation,migration,and invasion of SGC-7901 and the expression of p-Akt protein,while overexpression of COPB2 showed the opposite effect.In addition,knockdown of COPB2 inhibited SGC-7901 cell growth in vivo in a tumor xenograft model.CONCLUSION Knockdown of COPB2 expression can inhibit the proliferation,invasion,and metastasis of gastric cancer cells,and this effect may be related to the inhibition of AKT signaling activity.