AP-2α对大肠癌细胞侵袭生长及ER-β表达的影响

Objective: To study the effects of transcription factor activator protein-2α(AP-2α)on invasive growth and estrogen receptor-β(ER-β) expression in human colon cancer SW620 cells, and to probe into the involved molecular mechanism. Methods: Plasmid pcDNA3.1 (+)-AP-2α and pcDNA3. 1(+) were transfected into SW620 cells by liposome-mediated transfection. The adhesion, invasion and migration abilities of SW620 cells were measured by metrical gel adhesion assay and modified Boyden chamber (Transwell assay). The gene and protein expression levels of AP-2α and ER-β in SW620 cells were examined by Real-time PCR, Western blotting and immunofluorescence cytochemistry. The interaction between AP-2α DNA and ER-β in SW620 cells was measured by electrophoretic mobility shift assay (EMSA) after AP-2α gene transfection. Results: Overexpression of AP-2α markedly reduced the adhesion, invasion and migration abilities of SW620 cells (all P＜0.05); meanwhile, the mRNA and protein levels of ER-β in SW620 cells were also significantly enhanced (P＜0.05). EMSA results showed that AP-2α specifically bound to promoter region of ER-β gene in SW620 cells after transfection of pcDNA3.1 (+)-AP-2α plasmid. Conclusion: Overexpression of AP-2α can inhibit the adhesion, invasion and migration abilities of SW620 cells, which is probably related to ER-β expression in SW620 cells directly induced by interaction between AP-2α and promoter region of ER-β.