Abstract: AIM：To investigate the inhibitory and apoptosis effect of wild-type p53 (wt p53) gene transfection on human aortic smooth muscle cell (HASMC) lines and to explore a new way for prevention of restenosis following coronary artery stenting via wt p53 gene transfection into HASMCs. METHODS: HASMC lines were transfected by wt p53 gene coated by liposome of lipofectamine 2000. The expression of wt p53 protein in HASMC was determined by immunohistochemistry. Cell proliferation and the apoptosis of wt p53 gene on cell growth were detected by cell growth curve, WST-1 assay and flow cytometry. RESULTS: Immunohistochemistry staining showed that the protein of wt p53 gene was expressed in the cellular nucleus of HASMCs. Overexpression of wt p53 gene significantly decreased HASMC proliferation in vitro compared with that of control vector. Growth rate of HASMC/wt p53(+) was significantly lower than control. WST-1 test showed significant differences in cell viability between HASMC/wt p53 and control cells (P<0.05). FCM showed that the rate of HASMC/wt p53 apoptosis was >40%, significantly higher than control cells. CONCLUSION: Transfection of wt p53 gene obviously induces cellular inhibition and apoptosis in HASMCs, suggesting that wt p53 gene transfection into HASMCs can be an effective means for prevention and therapy of restenosis after coronary stenting.