Co-transfer of human wild-type p53 and granulocyte-macrophage colony-stimulating factor genes via recombinant adenovirus induces apoptosis and enhances immunogenicity in laryngeal cancer cells

Co-transfer of immunomodulatory and anti-proliferative genes may be the basis for new strategies to enhance tumor regression. The purpose of this study was to develop a combination gene therapy strategy for the treatment of laryngeal cancer. Human wild-type p53 and granulocyte-macrophage colony-stimulating factor (GM-CSF) genes were transferred into human laryngeal cancer cells mediated by adenovirus type 5 vector co-expressing human wild-type p53 and GM-CSF (Ad-p53/GM-CSF). By the introduction of the wild-type p53 gene, the growth of human laryngeal cancer Hep-2 cells was inhibited and their apoptosis was induced. By the introduction of the GM-CSF gene, the immunogenicity of cancer cells was enhanced. Significant proliferation of tumor infiltrating lymphocytes and tumor-specific cytotoxicity of cytotoxic T lymphocytes were induced by Ad-p53/GM-CSF-infected cancer cells in vitro. The results suggest that the co-transfer of human wild-type p53 and GM-CSF genes into tumor cells via recombinant adenovirus may be further developed into an effective and practical combination gene therapy strategy for laryngeal cancer.