RESUMO
Objective: To investigate the mechanism by which X-irradiation inhibited the invasion and metastasis of human lung adenocarcinoma cell line. Methods: A549 cells were irradiated with varying doses of 6 MV X-ray. Soft agar colony formation assay was employed to evaluate the effects of X-irradiation on the proliferation of A549 cells. RT-PCR and Western blotting were performed to analyze the protein and mRNA expression levels of E-cadherin and β-catenin. The invasion of A549 cells was evaluated by the Transwell chamber migration assay. Results: X-irradiation could inhibit the proliferation of A549 cells in a dose-dependent manner. The protein and mRNA expression levels of E-cadherin in A549 cells were higher than those in the control group (P 0.05). And the cell invasion capability was decreased with the increase in the dose of irradiation (P <0.05). Conclusion: X-irradiation up-regulated the expression of E-cadherin and β-catenin in A549 cells, which enhanced the intracellular adhesion and suppressed the invasion capability. That may be the mechanism for the inhibitory effects of X-irradiation on metastasis of human lung adenocarcinoma cell line.