A Bicistronic Adenoviral Vector Carrying Cytosine Deaminase and Granulocyte-Macrophage Colony-Stimulating Factor Increases the Therapeutic Efficacy of Cancer Gene Therapy

摘要

The combination of cytotoxic treatment modalities, including oncolytic viral gene therapies and immunotherapy, usually yields a synergistic effect. In the current study, a bicistronic adenoviral vector, Ad-CD-GMCSF, carrying the cytosine deaminase (CD) and granulocyte-macrophage colony-stimulating factor (GM-CSF) transcription units driven by a cytomegalovirus promoter was constructed, and the in vitro efficacy of the vector was tested in tumor cell lines and a syngeneic mouse model of colon cancer. The tumor cells infected with Ad-CD-GMCSF vector were found to produce a substantial amount of GM-CSF in tumor cell lines. Accordingly, the vector carrying CD and GM-CSF transcription units together induced a potent antitumor immunity with a significantly increased number of tumor-specific T cells and tumor-specific T-cell cytotoxicity (p?