Glutamate promotes secretion of MMP-2 and enhances invasion of glioma cells

Objective To investigate the mechanism of invasion of glioma evoked by glutamate.Methods Glioma cell line U251 was cultured in vitro; cell invasion of U251 was detected by Matrigel Transwell method 24 h after 100 μmol/L glutamate treatment; MMP-2 and MMP-9 secretions were detected by gelatin zymography assay 2,4,8 and 12 h afte glutamate treatment; the protein expression of extracellular matrix metalloproteinase inducer (EMMPRIN) was detected by Western blotting 3,6 and 9 h after glutamate treatment. Results Matrigel Transwell method indicated that the cells crossing the cytomembrane of U251 in the glutamate treatment group (37.44±2.31) were significantly increased as compared with those in the control group (25.89±3.00, P＜0.05); MMP-2 secretion in the glutamate treatment group 8 and 12 h afte glutamate treatment was obviously increased as compared with that in the control group (P＜0.05); while Western blotting indicated that no significant differences on the EMMPRIN level were noted between time points of 3, 6 and 9 h after glutamate treatment. Conclusion Glutamate promotes the secretion of MMP-2 in glioma cell line U251 to enhance the invasion of glioma cells; MMP-9 and EMMPRIN are not involved in the process of glutamate promoting the invading of U251. Key words: Glioma; Glutamate; Invasiveness; MMP-2