In phase 1 clinical trials of patients with recurrent or refractory ovarian cancer or multiple myeloma, administration of oncolytic MV strains engineered to express either the carcinoembryonic antigen (MV-CEA) or the sodium iodide symporter (MV-NIS) was associated with the development of tumor-specific immune responses and significant antitumor effects;22,23 treatment was well tolerated. The gene discussed is SLC5A5; the disease is ovarian cancer.