Effect of Ca2+ mobilization on release and activation of matrix metalloproteinases in hepatocellular carcinoma cells / 中华肿瘤杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of Ca(2+) mobilization on release and activation of matrix metalloproteinases (MMPs) in human hepatocellular carcinoma cells.</p><p><b>METHODS</b>Ca(2+) and chemicals which can induce or inhibit Ca(2+) mobilization were added into human SMMC-7721 hepatoma cells in vitro. SDS-PAGE protein electrophoresis and gelatin zymography analysis were carried out to detect the changes of release and activation of MMPs in the cell culture supernatant.</p><p><b>RESULTS</b>Addition of CaCl(2) into culture system resulted in an enhanced secretion and activation of MMP-2 and MMP-9 in a dose-dependent manner. At a dose of 0.8 mmol/L CaCl(2), it maintained a stable high level of MMPs, especially of MMP-2 with (109.71 +/- 27.93)% elevation as compared to the cells without CaCl(2) addition (P < 0.001). SDS-PAGE analysis showed that most secreted proteins were MMPs (MMP-2 and MMP-9) when the cells cultured in media without serum. Thapsigargin (Tg, 4 micromol/L), an inducer of intracellular Ca(2+) stores depletion, significantly enhanced the release and activation of MMP-2 and MMP-9, compared to the control with (58.63 +/- 31.04)% elevation (P < 0.05), while the inducing effect of Tg on MMPs release and activation was significantly inhibited by S-nitro-N-acetylpenicillamine (SNAP, 200 micromol/L), an NO donor.</p><p><b>CONCLUSION</b>Intracellular Ca(2+) regulation pathways may play an important role in the process of release and activation of MMPs.</p>