Abstract

Oncolytics: Genes and Viruses as Immunotherapies

E Antonio Chiocca, Harvey Cushing Professor of Neurosurgery and Chairman, Department of Neurosurgery, Brigham and Women's Hospital/Harvard Medical School

There are various types of immunotherapy for malignant tumors, such as glioblastoma. I plan to discuss the use of genetically engineered viruses to deliver cytotoxic, immuno-stimulatory genes into tumors. Two main types of viruses are used in this technology: [1]. Replication-defective vectors, where viral genes have been removed and thus there is no expression of viral genes or generation of progeny viruses, but there is expression of an immuno-stimulatory and/or cytotoxic gene, and [2]. Tumor replication-selective viruses (Oncolytic Viruses, OVs) where a viral pathogen is engineered so that its pathogenicity is now targeted to tumor and not normal cells. It is now recognized that the presence of viral genes and viral proteins in both of these technologies can elicit powerful anticancer immune responses which are a major component of efficacy.