Now that smallpox has been all but eradicated, it may be time to find a new use for the smallpox vaccine. Researchers at California-based biotech company Jennerex Biotherapeutics are using the vaccine to help liver cancer patients survive longer, reports New Scientist's Debora MacKenzie. The live virus in the vaccine, Vaccinia, is attracted to tumors, MacKenzie says. "It prefers to infect cancer cells because they turn off the antiviral protein interferon and turn on signaling molecules that attract Vaccinia," she adds. "Early experiments in a variety of tumors reported in 2007 suggested that this might make the virus, which has been used safely in millions of people, a revolutionary cancer treatment." Now, Jennerex researchers have genetically modified Vaccinia — one change deprives the virus of an enzyme found in cancer cells in abundance, in order to make cancer cells even more attractive to it than normal cells; and the other change causes the virus to make a protein that triggers an attack by the immune system. In a recent trial of 30 people with late-stage liver cancer, those given the vaccine survived twice as long as control patients — 14 months compared to seven, MacKenzie says.
A New Use for the Smallpox Vaccine
Nov 17, 2011