RESUMO
Objective To investigate the inhibitory effect of melatonin on the migration and invasion of gastric cancer cell and the underlying molecular mechanism. Methods Human gastric cancer SGC-7901 cells were treated with different concentrations of melatonin ( 0. 1, 1, 2 and 4 mmol/L ) for 24 hours, and the changes in the migration and invasion of gastric cancer cells were detected by scratch test and Transwell assay. The expressions of matrix metalloproteinase ( MMP) -2 and MMP-9 in the supernatant were detected by ELISA kit. The changes of MMP-2, MMP-9, intercellular cell adhesion molecule-1 ( ICAM-1 ) and CD44 expressions were detected by using Real-time PCR. The protein expressions of ICAM-1, CD44, p-P38, P38 and phosphorylated mitogen-activated protein kinase kinase ( p-MKK) 3/6 were detected by Western blotting. Results Melatonin inhibited the migration and invasion of gastric cancer cells in a dose- dependent manner. Compared with the blank control group, melatonin reduced the expression of MMP-2, MMP-9, ICAM-1 and CD44, and inhibited the expressions of p-P38, P38 and p-MKK3/6 in gastric cancer cells. Conclusion Melatonin inhibits the migration and invasion of gastric cancer cells by inhibiting the expressions of MMP-2, MMP-9, ICAM-1 and CD44. Inhibition may be related to the p38MAPK signaling pathway.
RESUMO
In order to investigate the role of melatonin in inhibiting the proliferation of murine gastric cancer and the underlying molecular mechanism, we performed an in vivo study by inoculating murine foregastric carcinoma (MFC) cells in mice, and then tumor-bearing mice were treated with different concentrations of melatonin (i.p.). The changes of Bcl-2, Bax, p21 and p53 expressions in tumor tissue were detected by using real-time fluorescence quantitative RT-PCR and Western blot. We found that: (1) melatonin resulted in reductions of tumor's volume and weight in the gastric cancer-bearing mice and thus showed anti-cancer effect; (2) melatonin reduced Bcl-2 expression, but increased the expression of Bax, p53 and p21 in tumor tissue. Our results suggest that melatonin could inhibit the growth of tumors in gastric cancer-bearing mice through accelerating the apoptosis of tumor cells.