Figure 5.

The effect of MMP-7 knockdown on cell proliferation. A) MTT assay was used to evaluate cell proliferative activity for consecutive 3 days; cell proliferative activity was remarkably diminished in a time-dependent manner in siMMP-7 group compared with the CON and NC groups (**P<0.01). B) [³H] thymi-dine incorporation into DNA was assessed by scintillation counting. Results are expressed as percentage of increase of [³H] thymi-dine incorporation in serum-stimulated cells over that of quiescent cells for each cell population, indicating that the increase of [³H]dT incorporation induced by serum was higher in CON and NC groups than in siMMP-7 group (**P<0.01). C,D) The expression level of PCNA protein, examined by Western blot assay, was downregulated in siMMP-7 group compared with the CON and NC groups (**P<0.01), suggesting that knockdown of MMP-7 might inhibit proliferation of LAC cells through downregulation of PCNA expression.