ABSTRACT
Endostatin can inhibit tumor growth by blocking angiogenesis, whereas tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) may function as a soluble cytokine to selectively kill cancer cells without toxicity to most normal cells. To establish the combined anti-tumor therapeutic effect of endostatin and soluble TRAIL (sTRAIL), we performed intra-tumoral human endostatin and sTRAIL gene transfer using plasmid pVAX1 as a vector in a nude mouse model of human liver cancer. For subcutaneously inoculated human BEL7402 cancer, co-expression of both transgenes conferred marked anti-tumor activity with a significant reduction in tumor vessel density and an increase in apoptotic rates, which was accompanied with a strong activation of caspase-3. Importantly, combination therapy employing one-half dose of endostatin and sTRAIL plasmids was more effective than single endostatin or sTRAIL therapy. These results indicate that a pVAX1-mediated combinatorial antiangiogenic and proapoptotic gene therapy approach involving endostatin and sTRAIL can be an effective novel form of treatment for human liver cancer.
