Local scientists are among researchers around the country working to resurrect a century-old idea: using vaccines in the hope they might help people avoid developing cancer.
Although most vaccines used today are considered effective in preventing other diseases, it’s not clear whether the idea will work with cancers.
“There’s no question that we can generate an immune response against a tumor,” said one University of Washington researcher, Dr. Nora Disis. The question, she said, is how to generate an immune response big enough to beat cancer.
“It has always seemed like a good idea, and it has never worked,” said Dr. Daniel Hayes, clinical director of breast cancer research at Georgetown University Medical Center.
Still, the UW project has a number of volunteers helping out.
“Somebody’s got to be the guinea pig,” said Connie Castle, a 50-year-old Spokane woman who has had breast and bone cancer. She is one of 10 women helping Disis and fellow researcher Dr. Mac Cheever test a breast-cancer vaccine. “I really wanted to do this because it might help me, and the research will help other women.”
“Most of the patients who volunteer are pretty set with the knowledge that they’re dying, or might be,” said Dr. Julie Gralow, a UW oncologist. “This is about altruism. They want to help others.”
Cancer vaccines were first tried around the turn of the century. One practitioner, a New York surgeon named William Coley, noticed that tumors regressed in some cancer patients who got bacterial infections.
So Coley infected cancer patients with killed bacteria and, in some cases, cured them of the cancer. But the results were unpredictable, and the idea of using the immune system to fight cancer eventually fell out of favor.
With today’s advanced knowledge about immunology, cancer and molecular biology, scientists are trying it again - although for now just as a treatment for people at high risk of recurrence rather than prevention.
Hayes said most cancer vaccines haven’t been specific enough to provoke an effective immune response against all the cancer cells.
Vaccines, he noted, are typically used to help the body protect itself against foreign invaders, while cancer is the body’s own cells running amok with unrestrained growth.
Still, Hayes and others say it’s worth another shot, with minimal risk.
“The toxicity (of a cancer vaccine) is amazingly low,” said Dr. Brenda Sandmaier at the Fred Hutchinson Cancer Research Center.
One potential risk from cancer vaccines is the possibility a patient’s immune system will react against healthy cells, Sandmaier said - the kind of syndrome that leads to illnesses such as rheumatoid arthritis and multiple sclerosis. But so far, there’s been little evidence to support that risk.
But the history of cancer vaccine research “has left a string of broken bodies and frustrated scientific careers,” Hayes said.