目的：探讨连接蛋白43（connexin 43，Cx43）对膀胱癌细胞侵袭能力的影响及其可能的作用机制。方法: 选取2014年6月至2015年9月间承德医学院附属医院泌尿外科52例膀胱癌手术组织标本及32例癌旁组织，以及人膀胱癌细胞株5637。用免疫组化方法检测膀胱癌组织中Cx43蛋白表达。将Cx43脂质体、空白脂质体、siRNA及siRNA对照质粒转染5637细胞，Western blotting验证过Cx43表达和干扰效果；用Transwell侵袭实验检测5637细胞侵袭能力的变化，用Western blotting检测5637细胞MMP-2、MMP-9和P-P38蛋白表达水平的变化。结果: 膀胱癌组织中Cx43蛋白的表达水平明显高于癌旁组织\[(5.21±0.33) vs（2.84±0.19），P<0.01\]。转染Cx43脂质体和siRNA成功上调/下调5637细胞中Cx43的表达。Cx43过表达组5637细胞的侵袭能力高于对照组\[穿膜细胞数：（1.36±0.04） vs （0.70±0.15）个，P<0.01\], siRNA干扰组细胞的侵袭能力低于对照组\[穿膜细胞数：（0.20±0.08） vs （0.59±0.13）个，P<0.05）。Cx43过表达组细胞MMP-2、MMP-9、P-P38/P38蛋白水平均高于对照组（P<0.01或P<0.05），siRNA干扰组均低于对照组低(均P<0.01)。结论: Cx43增强膀胱癌5637细胞的侵袭能力，其机制可能是通过激活P38/MAPK信号途径实现的。

Objective:To explore the effect of connexin 43(Cx43) on invasion ability of bladder cancer cells and the possible mechanisms. Methods: Fifty-two bladder cancer tissues and 32 precancerous tissues resected from June 2014 to September 2015 at the Department of Urology of the Affiliated Hospital of Chengde Medical University, as well as human bladder cancer 5637 cell line were collected for this study. Immunohistochemical method was used to detect the expression of Cx43 protein in bladder cancer tissues. Cx43 liposome plasmid (Transfection group), empty liposome plasmid (Transfection control group), siRNA (siRNA group) and siRNA control (siRNA control gorup) were transfected into bladder cancer 5637 cells. The efficiency of over-expression and knockdown was evaluated by Western blotting; the changes in invasion of bladder cancer cells were evaluated by Transwell assay. The changes in protein expressions of MMP-2, MMP-9, P38 and P-P38 were detected by Western blotting. Results: The expression of Cx43 protein in bladder cancer tissues was significantly higher than that in paracancerous tissues (\[5.21±0.33\] vs \[2.84±0.19\], P<0.01). Transfection of Cx43 liposome or siRNA successfully up-/down-regulated the expression of Cx43 in 5637 cells. Compared with control group, the migration ability of 5637 cells in Cx43 over-expression group was increased significantly (\[1.36±0.04\] vs \[0.70±0.15\]，P<0.01), while that of siRNA group was decreased significantly (\[0.20±0.08\] vs \[0.59±0.13\], P<0.05). The protein expressions of MMP-2, MMP-9, P-P38 and P38 in Cx43 liposome transfection group were significantly higher than those in control group (P<0.01 or P<0.05), while the expressions in siRNA group were significantly lower than those in the control group (all P<0.01). Conclusion: Cx43 could enhance invasion ability of bladder cancer cells, and the mechanism might be related with the activation of P38/MAPK signaling pathway.

承德市科学技术研究与发展计划项目（No.201422014）；承德医学院附属医院科研青年基金项目（No.201405）