全反式维甲酸对大肠癌细胞间隙连接蛋白Cx32与Cx43表达及增殖和迁移能力的影响

Effects of ATRA on Cx32 and Cx43 expressions and proliferation and migration abilities of colorectal cancer cells

目的:检测全反式维甲酸(ATRA)对大肠癌细胞Caco-2及SW480增殖、迁移及间隙连接蛋白Cx32与Cx43胞膜表达的影响,分析其对大肠癌效应作用机制。方法:取对数生长期大肠癌细胞分为ATRA处理组及阴性对照组,以1×10-8、1×10-7、1×10-6、1×10-5及1×10-4 mol·L-1 ATRA处理Caco-2及SW480细胞,应用MTT法测定其生长抑制率;以1×10-5及1×10-4 mol·L-1 ATRA处理SW480细胞,应用划痕法测定其迁移率,流式细胞术测定Cx32及Cx43胞膜阳性率。结果:与阴性对照组比较,ATRA处理组Caco-2及SW480细胞经1×10-4 mol·L-1 ATRA作用24、48及72h后,生长抑制率明显提高(P<0.01);ATRA处理组SW480细胞经1×10-5 mol·L-1 ATRA作用24和48h后,平均迁移率明显低于阴性对照组(P<0.05)。ATRA处理组SW480细胞经1×10-5及1×10-4 mol·L-1 ATRA作用24和48h后,胞膜Cx32及Cx43表达阳性率明显高于阴性对照组(P<0.05)。结论:ATRA可增加大肠癌细胞Cx43及Cx32膜表达,并抑制其增殖及迁移能力,其效应机制可能涉及间隙连接蛋白的胞内蛋白相互作用及细胞间通讯联系功能改变。

Objective To investigate the effects of ATRA on the proliferation and migration abilities and membranous distribution of Cx32 and Cx43 of colorectal cancer cells Caco-2 and SW480 and to elucidate the potential mechanism.Methods The colorectal cancer cell lines Caco-2 and SW480 were divided into ATRA treatment groups and control groups.The Caco-2 and SW480 cells were treated with 1×10-8,1×10-7,1×10-6,1×10-5 and 1×10-4 mol·L-1 ATRA,and MTT assay was applied to detect the inhibitory rates of growth of Caco-2 and SW480 cells.After the SW480 cells were treated with the 1×10-5 and 1×10-4 mol·L-1 ATRA,the wound healing assay was employed to determine the cell migration ability and flow cytometry was used to analyze membranous distribution of Cx 32 and Cx 43 in SW480 cells.Results Compared with control group,the growth inhibitory rates of Caco-2 and SW480 cells in ATRA groups after treated with 1×10-4 mol·L-1 for 24,48 and 72 h were significantly increased(P<0.01);the migration abilities of SW480 cells were dramatically decreased after treated with 1×10-5 mol·L-1 ATRA for 24 and 48 h(P<0.05);the membranous distribution of Cx 32 and Cx 43 of SW480 cells was remarkably increased after treated with 1×10-5 and 1×10-4 mol·L-1 ATRA for 24 and 48 h(P<0.05).Conclusion ATRA could increase the membranous distribution of Cx32 and Cx43 of colorectal cancer cells and inhibit the proliferation and migration abilities,which may be involved in the interaction between connexins and cytoplasmic proteins,as well as alteration of gap junctional intercellular communication.