层粘连蛋白反义RNA对TGFβ_1调节五种细胞内信号分子表达的影响

Effect of laminin antisense RNA on the expression of five intracellular proteins stimulated by transforming growth factor β_1

目的 明确转化生长因子 (transforming growth factorβ1 ,TGFβ1 )对大肠癌细胞 E-钙粘着蛋白、α-、β-、γ-连环蛋白及粘着斑激酶 (focal adhesion kinase,FAK)的影响 ,明确层粘连蛋白 (laminin,L M)反义 RNA对上述表达的调节作用。方法 采用免疫印迹技术检测各蛋白的表达水平 ,采用增强的化学发光技术显示结果。结果 TGFβ1 可促进α-和γ-连环蛋白表达。该表达不受 L M反义 RNA的影响 ;TGFβ1可促进 E-钙粘着蛋白表达 ,但 L M反义 RNA既可抑制 E-钙粘着蛋白表达 ,又能抑制 TGFβ1 对该蛋白的调节作用 ;TGFβ1 只有在 L M反义 RNA存在下才具有抑制 FAK表达的作用。结论 TGFβ1 对肿瘤恶性表型的抑制作用可能与 E-钙粘着蛋白、α-、γ-连环蛋白表达增加有关 ,E-钙粘着蛋白和 FAK表达的改变可能是 TGFβ1 通过影响 L M的表达间接作用所致。 TGFβ1 对肿瘤细胞表型的影响是多种蛋白综合作用的结果。

Objective To investigate the effect of laminin antisense RNA on the expression of E cadherin, α , β ,γ catenins and focal adhesion kinase(FAK) stimulated by transforming growth factor β 1 (TGFβ 1). Methods Western blot technique was used to study their expression at protein level with ECL reagent. Results The expression of α and γ catenins was up regulated by TGFβ 1 without the interference of laminin antisense RNA. The up regulation of E cadherin stimulated by TGFβ 1 was inhibited in the presence of laminin antisense RNA. No change was found in the expression of FAK when stimulated by TGFβ 1, alone, but its expression was down regulated with the help of laminin antisense RNA.Conclusion The inhibition of TGF β 1 on the malignancy of colon cancer cell may partially be mediated by the up regulation of E cadherin and catenins.The effect of TGF β 1 on the expression of E cadherin and FAK may be the secondary results of the change in laminin expression.