[Effect of Ca2+ mobilization on release and activation of matrix metalloproteinases in hepatocellular carcinoma cells].
OBJECTIVE
To investigate the effect of Ca(2+) mobilization on release and activation of matrix metalloproteinases (MMPs) in human hepatocellular carcinoma cells.


METHODS
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.


RESULTS
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.


CONCLUSIONS
Intracellular Ca(2+) regulation pathways may play an important role in the process of release and activation of MMPs.
Jiang
Jian-li
JL
Cell Engineering Research Center, the Fourth Military Medical University, Xi'an 710032, China.
Yao
Xi-ying
XY
Zhou
Jun
J
Huang
Yong
Y
Chen
Zhi-nan
ZN
D002118:Calcium / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000201:enzymology* / Q000473:pathology; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology* / Q000473:pathology; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives / Q000494:pharmacology; D019284:Thapsigargin / Q000494:pharmacology
D020030:Nitric Oxide Donors; C110881:S-nitro-N-acetylpenicillamine; D019284:Thapsigargin; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D010396:Penicillamine; D002118:Calcium