Enhancement of 5-fluorouracil cytotoxicity on human colon cancer cells by retrovirus-mediated Interferon-α gene transfer

Gene therapy has advantages in the treatment of a variety of disorders due to its selective expression within specific mammalian cells. Several reports documented the clinical effects of interferon-α (IFN-α) in management of patients with advanced colorectal carcinoma. We report for the first time, the successful transduction of human IFN-α gene into colon cancer cells, COLO 201 using a replication-defective retroviral vector. Retrovirus-containing supernatant from PA 317 packaging cells was used to infect colon cancer cells, COLO 201 and NIH 3T3 cells. Transient infection showed that cell proliferation and cell viability were significantly suppressed in colon cancer cells transduced with IFN-α gene. Moreover, IFN-α-transduced cells acquired less resistance to 5-FU induced apoptosis. These data demonstrate that IFN-α gene transfer may have a clinical application and can be combined with chemotherapy for treatment of advanced colorectal cancer.