Stat3信号传导通路对结肠癌细胞G1～S期的调控

目的：探讨Stat3信号传导通路对结肠癌细胞G1-S期调控的可能机制。方法：应用阳离子脂质体介导Stat3反义寡核苷酸转染人结肠癌SW480与HCT116细胞，阻断其Stat3通路；MTT法检测细胞增殖状态；流式细胞术检测细胞周期；Western blot检测Stat3、磷酸化Stat3、G1期Cyclins、CDKs、p21、p27的表达。结果：转染Stat3反义寡核苷酸后结肠癌细胞增殖受抑制，Stat3、磷酸化Stat3、G1期Cyclins、CDKs表达水平下降，p21与p27表达水平上升。结论：Stat3信号传导通路可能通过调节CDK/Cyclin复合物与CK1成员之间的平衡而调节结肠癌细胞G1-S期转换。

Stat3 signal transduction pathway orchestrates G1 to S cell cycle transition in colon cancer cells

Objective:To show that Stat3 plays a key role in the G 1 to S phase transition in colon cancer cells. Methods: Human colon cancer cell lines SW480 and HCT116 were transfected with Stat3 antisense oligonucleotide mediated by liposome, MTT assay was used to measure the proliferation, flow cytometry was applied to analyze the cell cycle, and the expressions of Stat3, phosphorylation specific Stat3 (tyrosine 705), Cyclin D1, Cyclin E, CDK2, CDK4, CDK6, p21 and p27 were measured by western blot. Results: SW480 and HCT116 colon cancer cell lines expressed constitutively activated Stat3. Targeting of Stat3 using antisense oligonucleotide which directed against the translation site resulted in growth inhibition, downregulation of Stat3, p Stat3, Cyclins and CDKs, and upregulation of p21 and p27. Conclusion: Our findings suggest that Stat3 plays an important role in the G 1 to S phase transition in colon cancer cells, Stat3 orchestrates cell cycle by regulating the balance between CDK/Cyclin complex and CKI.