Patterns of Gelatinase-B Expression in Leukemic Cell Lines

Background: gelatinase-b named mmp-9 (matrix metalloproteinase-9), is a protease that degrades collagen type іv and v of extracellular matrix. mmp-9 production is increased in various types of cancers including leukemia and has an essential role in tumor invasion, metastasis and angiogenesis. in this study, patterns of mmp-9 activity in a number of leukemic cells have been evaluated in-vitro.materials and methods: human leukemic t cells (jurkat and molt-4) and monocyte (u937) were cultured in complete rpmi-1640 medium. then the cells were seeded at a density of 10 6 cells/ml and were incubated with different concentrations of pma (1-25ng/ml) or pha (1-10 μg/ml) for 24 hours. afterwards, mmp-9 activity and mmp-9 protein level in cell-conditioned media were evaluated by gelatin zymography and ecl western blotting, respectively.results: pha/ pma significantly induced mmp-9 activity in molt-4 and jurkat cells after 24-hour incubation in a dose-dependent manner compared with untreated control cells. moreover, pha/ pma extensively and dose-dependently augmented mmp-9 activity in u937 cells after 24-hour incubation time compared with untreated control cells. besides, pha/ pma increased mmp-9 level in u937 cells after 24-hour incubation time as was detected by western blotting compared with untreated control cells. conclusion: according to the results of this study, human leukemic jurkat, molt-4, and u937 cells could exhibit mmp-9 activity with different extents. among these cell lines, it seems that molt-4 and u937 human leukemia cell lines, which greatly show mmp-9 activity after stimulation with pha or pma, may provide valuable tools for screening mmp enhancers or inhibitors and for assessment of regulatory echanisms of mmp activity.