大肠癌细胞层粘连蛋白反义RNA对其受体功能的影响

Effect of laminin antisense RNA on the expression of laminin receptor and its function

目的明确转化生长因子(transforming growth factorβ,TGFβ)对大肠癌细胞层粘连蛋白(laminin,LM)及其受体功能的影响。明确层粘连蛋白反义RNA对上述表达的调节作用。方法采用125I-LM饱和结合剂量检测方法测定LM受体总数量;细胞表面核素标记-免疫沉淀技术检测细胞表面α6、β1整合素(功能最强的LM受体)含量;细胞粘附及α6、β1整合素抗体阻断技术检测LM受体功能。结果TGFβ可以刺激LM受体的表达,还可以促进细胞与细胞外基质LM的粘附。α6、β1整合素在细胞与LM粘附过程中起着重要作用。LM反义RNA既可抑制细胞与LM的粘附,又能抑制TGFβ对其的调节作用。同时,LM反义RNA还可以抵消TGFβ诱导的α6、β1整合素的高表达。结论TGFβ对肿瘤恶性表型的作用可能与LM及其受体的表达和功能有关。

Objective To investigate the effect of the expression of laminin(LM) on the expression of LM receptors and their function stimulated by transforming growth factor β. Methods The laminin binding receptors were identified by ^(125)I-laminin saturation binding assays. The function of LM receptors were detected by cell-surface rediolabeling and immunoprecipitatiom. And antibody-blocking experiments were performed to determine the role of α6 and β1 intergrins in cellular adhesion to ECM laminin. Results The expression of LM receptors were up regulated by TGFβ with the help of α6 and β1 intergrins. The adhesion to ECM and the high expression of α6 and β1 intergrins stimulated by TGFβ was inhibited in the presence of laminin antisense RNA. Conclusion The effect of TGFβ1 on the malignancy of colon cancer cell may partially be concerned with the expression and function of LM receptors.