The study on epithelial-mesenchymal transition induced by X-ray radiation in human colorectal carcinoma SW480 cells and its potential mechanism / 肿瘤

ABSTRACT

Objective: To investigate the effect of X-ray irradiation on epithelial-mesenchymal transition (MET) in human colorectal cancer SW480 cells and its involved potential signaling pathway. Methods: SW480 cells were irradiated with different doses of X-ray (0, 2, 4, 6 and 8 Gy). The migration and invasion abilities of SW480 cells after irradiation were detected by Transwell method. The expression levels of E-cadherin (E-cad), vimentin, K-ras and Smad3 mRNAs and proteins in SW480 cells were detected by real-time fluorogenic quantitative-PCR and Western blotting, respectively. Results: The migration and invasion abilities of SW480 cells after irradiation with X-ray were increased as compared with that of the control cells (no irradiation) (P < 0.05). The mRNA and protein expression levels of E-cad and K-ras were significantly decreased while the expression levels of vimentin mRNA and protein were significantly increased after irradiation as compared with those of the control cells (all P < 0.05). The expression level of Smad3 mRNA and protein in transforming growth factor-p1 (TGF-p1)/Smad3 signaling pathway were also increased (both P < 0.05) after irradiation. Conclusion: The results of this study support that X-ray irradiation can induce EMT of human colorectal cancer SW480 cells, and this effect may be related to the activation of TGF-β1/Smad3 signaling pathway.