间隙连接蛋白32,43的表达对胃癌侵袭转移潜能的影响

目的:研究间隙连接蛋Cx32,Cx43表达水平对胃癌侵袭转移潜能的影响．方法:采用免疫组化SP法和间接免疫荧光方法分别检测Cx32,Cx43在正常胃组织及不同病理分型的胃癌组织和不同分化程度胃癌细胞株中的表达,并分析该蛋白表达对胃癌侵袭转移潜能的影响．结果:免疫组化SP法结果显示:Cx32,Cx43 阳性棕黄色颗粒位于细胞膜和细胞质内,在正常胃组织中的阳性表达率显著高于胃癌组织(Cx32:X2=23．1,P<0．05,Cx43:X2=11．6, P<0．05),Cx32,Cx43在高中分化胃癌的阳性表达率显著高于低分化胃癌(Cx32:X2= 32．1,P<0．05;Cx43:X2=22．6,P<:0．05)．间接免疫荧光法结果显示:在转化的人胃细胞系 (GES-1)、胃高分化腺癌细胞系(N87)中Cx32, Cx43的表达均为阳性,但表达率和表达部位有显著差异．在GES-1中Cx32,Cx43绿色荧光沿其细胞膜呈颗粒状或细线状分布,其阳性表达率均为100％;在N87中,Cx32绿色荧光沿其细胞膜呈颗粒状或细线状分布,其阳性表达率为49%,而Cx43荧光分布在其细胞质中,其阳性表达率为55％;在BGC-823中Cx32,Cx43的表达均为阴性．结论:Cx32,Cx43是影响胃癌转移潜能的一个重要因素．

Relations of connexin 32 and 43 expression with metastatic potential of gastric cancer

AIM: To investigate the relationship between the expression of connexin (Cx) 32 and 43 and metastatic potential of gastric cancer. METHODS: Indirect immunofluorescent method and SP immunohistochemistry were used to examine the expression of Cx32 and Cx43 in gastric tissues from normal controls and patients with carcinoma of variously differentiated grades as well as in the gastric cancer cells of variously differentiated degree, and the relations of Cx expression with metastatic potential of gastric cancer were analyzed. RESULTS: Immunohistochemistry showed that the positive staining of Cx32 and Cx43 was located at cell membrane and cytoplasm, and the positive rate of Cx expression was significantly higher in normal gastric tissues than that in cancer tissues (Cx32: X2 = 23.1, P < 0.05; Cx43: X2 = 11.6, P <0.05). The positive rate of Cx expression was markedly higher in well-differentiated gas- tric cancer tissues than that in poorly-differentiated cancer ones (Cx32: X2 = 32.1, P < 0.05, Cx43: X2 = 22.6, P < 0.05). Indirect immunofluorescence showed that the expression of Cx32 and Cx43 were both positive in human gastric mucosal epithelial cell line (GES-1) and human well-differentiated gastric cancer cell line (N87), but the distributions and positive rates were significantly different between the two kinds of cell lines. Cx32 and Cx43 distributed granularly or linearly along the cell membrane with positive rates of both 100% in GES-1 cells. However, Cx32 located granularly or linearly along the membrane with a positive rate of 49%, and Cx43 was found in the cytoplasm with a positive rate of 55% in N87 cells. Cx32 and Cx43 were negatively expressed in the lowly-differentiated gastric cell line (BGC-823). CONCLUSION: Cx32 and Cx43 are important factors in influencing the occurrence, development and metastatic potential of gastric cancer.