Hedgehog通路对乳腺癌细胞增殖和凋亡的作用及其对Cx32和Cx43表达的影响

目的: 研究Hedgehog通路对乳腺癌细胞增殖、凋亡及间隙连接蛋白32(Cx32)和间隙连接蛋白43(Cx43)表达的影响,探讨其在乳腺癌细胞增殖和转移中的作用机制。方法: 取对数生长期乳腺癌MCF-7细胞分为环巴胺组和空白对照组,环巴胺组分别以5、10、20、30和40 μmol·L^-1环巴胺处理MCF-7细胞24、48和72 h,应用MTT法测定各组MCF-7细胞增殖抑制率。以0(阴性对照组)和25 μmol·L^-1环巴胺处理MCF-7细胞48 h后,AnnexinⅤ/PI双染流式细胞术检测细胞凋亡率及Cx32、Cx43胞膜阳性表达率。结果: 与空白对照组比较,各剂量环巴胺组MCF-7细胞增殖抑制率明显升高(P<0.05),且随环巴胺剂量增加和作用时间延长其增殖抑制作用增强;与空白对照组比较,25 μmol·L^-1环巴胺组48 h时,MCF-7细胞凋亡率明显升高(P<0.05)。与阴性对照组比较,25 μmol·L^-1环巴胺组48 h时,MCF-7细胞胞膜Cx32和Cx43阳性表达率明显升高(P<0.05)。结论: Hedgehog通路可抑制乳腺癌细胞凋亡,并调节Cx43和Cx32的胞膜表达。

Effects of Hedgehog on proliferation and apoptosis of breast cancer cells and its influence in Cx32 and Cx43 expressions

Objective:To study the effects of Hedgehog signal transduction pathway on the cell proliferation, apoptosis and connexin 32 (Cx32)and connexin 43 (Cx43)membranous distribution of breast cancer cells,and to explore its mechanism in the cell proliferation and metastasis of breast cancer.Methods:The breast cancer MCF-7 cells at logarithmic growth period were divided into cyclopamine groups and blank control groups. The MCF-7 in cyclopamine groups were treated with 5,10,20,30 and 40μmol·L-1 for 24,48 and 72 h;MTT assay was applied to detect the inhibitory rate of proliferation of MCF-7 cells. After the MCF-7 cells were treated with 0 (negative control group)and 25μmol·L-1 cyclopamine for 48 h,flow cytometry was employed to determine the apoptotic rate and to analyze membranous distribution of Cx32 and Cx43 in the MCF-7 cells.Results:Compared with blank control group,the inhibitory rates of proliferation in cyclopamine groups were increased (P<0.05), and the inhibitory effect of proliferation was increased with the increasing of cyclopamine doses and prolongation of treatment time.After treated with 25μmol·L-1 cyclopamine,the apoptotic rate of MCF-7 cells was higher than that in blank control group (P<0.05).The positive expression rates of Cx32 and Cx43 48 h after treatment were higher than those in negative control group (P<0.05).Conclusion:Hedgehog signal transduction pathway can inhibit the apoptosis and mediate membranous distribution of Cx32 and Cx43 in breast cancer cells.