Stat5b/Survivin信号转导通路调控结肠癌细胞凋亡的机制

目的: 探讨Stat5b/Survivin信号转导通路调控结肠癌细胞凋亡的作用机制。方法: 用阳离子脂质体介导Stat5反义寡核苷酸转染人结肠癌HT29细胞，MTT法检测细胞增殖状态；流式细胞术检测细胞周期与凋亡；EMSA检测Stat5活性；Western blotting检测Stat5、p-Stat5、cyclin D1、Survivin与Bcl-2凋亡家族成员Bcl-2和Bcl-x_L的表达。结果: 转染Stat5反义寡核苷酸后HT29细胞增殖受抑制，凋亡细胞增多，Stat5、p-Stat5与Survivin表达下降，Bcl-2与Bcl-x_L变化不明显。结论: 阻断Stat5通路可以抑制靶基因Survivin表达并诱导结肠癌细胞凋亡。

Stat5b signaling pathway regulates the expression of Survivin and promotes apoptosis in human colon cancer cells

AIM: The purpose of the study was to examine colon cancer cell lines to determine whether Stat5b/Survivin plays an important role in the process of apoptosis in colon cancer cells. METHODS: Protein lysates were extracted from colon cancer cells. Human colon cancer cell line HT29 was transfected with Stat5b antisense oligonucleotide mediated by liposome. MTT assay was used to measure the proliferation. Flow cytometry was applied to analyze the cell cycle and apoptosis. EMSA was used to detect the activity of Stat5. Western blotting was applied to measure the expression of Stat5, p-Stat5, cyclin D1, Survivin, Bcl-2 and Bcl-xL. RESULTS: Targeting of Stat5 using antisense oligonucleotide against the translation site resulted in apoptosis and downregulaed the expressions of Stat5, p-Stat5, cyclin D1 and Survivin, but not Bcl-2 and Bcl-xL. CONCLUSION: Constitutive activation of Stat5 is associated with the carcinogenesis of colon cancer cells. Blocking of Stat5 signaling inhibits the expression of Survivin and induces apoptosis in colon cancer cells.