AIM: To investigate the effects of KN-93, a CaMKII selective inhibitor on cell 
proliferation and the expression of p53 or p21 protein in human hepatic stellate 
cells.
METHODS: Human hepatic stellate cells (LX-2) were incubated with various 
concentrations (0-50 micromol/L) of KN-93 or its inactive derivative, KN-92. 
Cell proliferation was measured by CCK-8 assay, and the expression of two cell 
cycle regulators, p53 and p21, was determined by SDS-PAGE and Western blotting.
RESULTS: KN-93 (5-50 micromol/L) decreased the proliferation of human hepatic 
stellate cells in a dose-dependent manner from 81.76% (81.76% +/- 2.58% vs 
96.63% +/- 2.69%, P < 0.05) to 27.15% (27.15% +/- 2.86% vs 96.59% +/- 2.44%, P < 
0.01) after 24 h treatment. Incubation of 10 micromol/L KN-93 induced the cell 
growth reduction in a time-dependent manner from 78.27% at 8 h to 11.48% at 48 
h. However, KN-92, an inactive derivative of KN-93, did not inhibit cell 
proliferation effectively. Moreover, analysis of cell cycle regulator expression 
revealed that KN-93 rather than KN-92 reduced the expression of p53 and p21.
CONCLUSION: KN-93 has potent inhibitory effect on proliferation of LX-2 cells by 
modulating the expression of two special cell cycle regulators, p53 and p21.