Antitumor effects of a recombinant pseudotype baculovirus expressing Apoptin in vitro and in vivo

Apoptin, a chicken anemia virus-derived, p53-independent, bcl-2-insenstive apoptotic protein with the ability to specifically induce apoptosis in tumor or transformed cells, is a promising tool for cancer gene therapy. In this study, pseudotype baculovirus, a recently developed alternative gene delivery system, was used as a vector to express Apoptin. The resultant recombinant baculovirus (BV-Apoptin) efficiently expressed the Apoptin protein and induced apoptosis in HepG2 and H22 cells. Studies in vivo showed that intratumoral injection of BV-Apoptin into a xenogeneic tumor (derived from H22 murine hepatoma cells in C57BL/6 mice) significantly suppressed tumor growth, and significantly prolonged the survival of tumor-bearing mice compared to a control pseudotype baculovirus that expressed EGFP. Taken together, these results suggest that Apoptin, expressed from the pseudotype baculovirus vector, has the potential to become a therapeutic agent for the treatment of solid tumors.