Effects of human tissue kallikerin gene delivery on proliferation and migration of vascular smooth muscle cells

AIM: To investigate the effects of adenovirus-mediated human tissue kallikerin (Ad-hKLK1) gene delivery on the proliferation, migration of VSMCSHR induced by platelet derived growth factor-BB (PDGF-BB). METHODS: The VSMCSHR proliferation induced by PDGF-BB was accessed by cell counting and methyl thiazolyl tetrazoliuin (MTT). The migration was assessed by modified Boyden chamber assay. Western blotting was used to determine the expressions of the cycle-independent kinase inhibitors p27Kip1 and p21Cip1.RESULTS: Proliferation of VSMCSHR induced by PDGF-BB was inhibited after transfection of Ad-hKLK1 (20-100 MOI) in a MOI-dependent manner. The peak inhibition titer of Ad-hKLK1 fell on 100 MOI, with the peak inhibition rate of 39.3% (cell counting, n=3, P<0.01), 30.2% (MTT, n=3, P<0.01), peak stunning rate of cell-cycle in phase G0/G1 at 36.4%. The inhibitory effects of proliferation and cell-cycle caused by hKLK1 gene delivery were significantly abolished by Hoe140, a bradykinin B2 receptor antagonist. Migration of VSMCSHR induced by PDGF-BB was inhibited after hKLK1 gene delivery, with the peak inhibitory rate of 34.6% (n=6, P<0.01). However the inhibitory effects of migration were not blocked by Hoe140. The protein expression of p27Kip1 and p21Cip1 increased significantly after the hKLK1 gene delivery, whereas Hoe140 nearly completely blocked these effects (n=3, P<0.01, respectively).CONCLUSION: The hKLK1 gene delivery may inhibit the proliferation and migration of VSMCSHR induced by PDGF-BB. Bradykinin B2 receptor probably mediates the up-regulating expression of p27Kip1 and p21Cip1 that contributes to the inhibitory effects of proliferation of hKLK1. However, the inhibitory effects of migration by hKLK1 gene delivery may not be mediated by bradykinin B2 receptor.