The results demonstrated that combined administration of p21(WAF-1) and GM-CSF could remarkably inhibit the growth of subcutaneously transplanted hepatomaHepa cells, and significantly increase the survival rate of tumor-bearing mice.
The results showed that combined gene transfer of p21WAF-1 and GM-CSF could inhibit the growth of pre-established tumor more effectively and prolong the survival time of hepatoma-bearing mice more significantly than the transfer of a single gene.
Therefore, these results suggest that combining expression of GM-CSF and B70 may enhance NK-mediated cytotoxicity, and then induce the antitumor immunity in hepatoma transplanted into nude mice.
To test whether antitumor activity could be increased by combining the above two mechanisms, this study examined the therapeutic effect of combination gene therapy using a murine granulocyte-macrophage colony-stimulating factor (mGM-CSF) gene and a human endostatin (hED) gene on a rat orthotopic liver tumor model.