Matt Safford in Smithsonian:
The notion of using viruses to attack cancer has been around nearly as long as we’ve known about viruses themselves. But several roadblocks– viruses attacking patients’ immune systems, or, not effectively targeting tumors–have led to slow growth in this area of research. Until now.
Earlier this month, a team led by Dr. Stephen Russell at Minnesota’s Mayo Clinic announced that a patient with previously unresponsive, blood-borne cancer (multiple myeloma) had gone into complete remission after being treated with a massive dose of a modified measles virus. A second patient given a similar dose (10 million times the amount in the common measles vaccine) didn’t respond as dramatically to the treatment, but the patient’s tumors did shrink, indicating the virus was at least attacking the targeted areas.
In a separate study that hasn’t yet made it to human trials, a team led by Dr. Khalid Shah at the Harvard Stem Cell Institute (HSCI) at Massachusetts General Hospital has made progress in attacking brain tumor cells in mice using the herpes virus. Shah’s team packed the virus inside a type of human stem cell which, unlike some previous vehicles, is amenable to carrying modified viruses and doesn’t trigger a significant immune response. The team’s second trick: They wrapped the herpes-loaded stem cells inside a biocompatible gel to help keep the virus in place and attacking tumor cells for a longer period of time. According to the team, mice treated in this way had significantly improved survival.