Antitumor effect of adenovirus-mediated Bax gene transfer on p53-sensitiveand p53-resistant cancer lines

Antitumor effects of the proapoptotic Bar gene have been evaluated in vitro and in vivo by a binary adenovirus system expressing the human Bar gene. O verexpression of the Bar gene in cultured cell fines from human lung carcin oma results in caspase activation, apoptosis induction, and cell growth sup pression. Intratumoral injection of adenovirus vector expressing the Bar ge ne suppressed growth of human lung cancer xenografts established in nude mi ce, Histological examination of tumors from mice treated with the Bar gene demonstrated high levels of Bar expression and extensive apoptosis in tumor s. In comparison with the treatment by an adenoviral vector expressing huma n p53, the Bar gene can effectively suppress tumor growth in both p53-sensi tive and p53-resistant human lung carcinoma cell lines. Toxicity was not de tected in liver and other systems in animals treated intralesionally with t he Bar gene. Therefore, our results suggest that the Bar gene may be useful in cancer treatment.