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

Antitumor effects of the proapoptotic Bax gene have been evaluated in vitro and in vivo by a binary adenovirus system expressing the human Bax gene. Overexpression of the Bax gene in cultured cell lines from human lung carcinoma results in caspase activation, apoptosis induction, and cell growth suppression. Intratumoral injection of adenovirus vector expressing the Bax gene suppressed growth of human lung cancer xenografts established in nude mice. Histological examination of tumors from mice treated with the Bax gene demonstrated high levels of Bax expression and extensive apoptosis in tumors. In comparison with the treatment by an adenoviral vector expressing human p53, the Bax gene can effectively suppress tumor growth in both p53-sensitive and p53-resistant human lung carcinoma cell lines. Toxicity was not detected in liver and other systems in animals treated intralesionally with the Bax gene. Therefore, our results suggest that the Bax gene may be useful in cancer treatment.