Polio vs. Cancer: Who Wins?

Researchers at Duke Cancer Institute have piloted a breakthrough cancer therapy using an unlikely ally: the polio virusThe smallest type of organism known. A single virus particle (called a virion) is much smaller than a cell. Viruses reproduce by invading cells and forcing the cells to make progeny virions. Viruses generally have specific host cells which they infect. Some virus types are associated with specific cancers and can convert normal cells into cancer cells. Examples of viruses associated with cancer are: papillomavirus-cervical cancer, hepatitis virus-liver cancer, Epstein-Barr virus-Burkitt's lymphoma. Virus-induced transformation of cells was one of the very first model systems for the study of cancer. Viruses have also been a key tool in the identification of many oncogenes. Because of their great ability to enter target cells viruses such as adenoviruses are being examined for their ability to deliver genes to cancer cells..

After years of studying the virus famous for its destructive behavior, scientists have genetically modified polioviruses to help humans instead of hurt them. They have succeeded in creating a version of the virus that is able to attach to tumor cells. The virus destroys the tumor cells, causing a release of molecules that alert the immune system to the presence of the tumor. Once alerted, the immune system is able to identify and attack the remaining tumor cells. This therapy gave promising results in a trial of patients with recurrent glioblastoma, a deadly brain cancer.  More research is being done on the activity of the immune system in patients treated with poliovirus.