To some it may seem counterintuitive to use an infection to cure a disease. Surprisingly enough, this is exactly what researchers have been doing using oncolytic virus therapy. Oncolytic viruses are naturally occurring or engineered viruses that selectively target cancer cells by identifying common cancer characteristics such as defective immune responses or abnormalities in cellular signaling pathways. Once viruses infect the cancer cells, they replicate within the cell and eventually kill it. As such, the infectious qualities of oncolytic viruses are becoming increasingly useful tools during cancer treatment.
Past studies have shown great potential for oncolytic therapy using vesicular stomatitis virus, (VSV) -- a negative-strand RNA virus that generally infects insects, cattle, horses and pigs (1). VSV has proven to be particularly conducive to oncolytic virus therapy as a result of its small easily manipulated genome and relative innocuity in humans (2). So far, VSV vectors have been used for immunization against HIV and influenza (2,3). Additionally, testing has occurred that suggests that there is also potential of VSV as a recombinant cancer vaccine vector (4).
Despite the high hopes for the use of VSV as oncolytic cancer treatment, a recent 2012 study suggests that human pancreatic ductal adenocarcinoma (PDA) cells do not consistently permit VSV infection (5). In some cases, PDA cells retained all resistance and were still able to activate functional interferon (IFN) responses. As a result, the study of the interferons – proteins released by host cells to interrupt viral replication – and their association with oncolytic VSV infection is of great interest to researchers.