Polio, Herpes, and Other Viruses Treat Cancer
NEW YORK—The word “virus” conjures up images of nasty, wormlike organisms, mean-looking spiked balls, and a fear of infectious, unseen pathogens lurking on public transit and playgrounds, ready to attack.
But the picture is a lot more nuanced. Our bodies actually harbor a huge host of viruses, and more and more research is showing that these viruses help our immune systems out in important ways.
Although the medical community has known about oncolytic viruses for over a century, it’s only now that their power is being harnessed for viable cancer treatments.
Doctors have known about oncolytic viruses since the mid-1800s (since before they even really knew what a virus was), when they started reporting that tumors sometimes went into remission for a while following a bout of natural viral infection.
Sometimes it was infection with the measles or the flu, and in at least one case, the chicken pox caused temporary regression of lymphatic leukemia.
In the 1950s and ’60s, the ability to propagate viruses in the lab instead of only in living organisms, made it possible for researchers to begin exploring the potential of oncolytic viruses to cure cancer.
By the 1990s, genetic engineering allowed researchers to create viruses that more specifically targeted cancer cells and left healthy cells pretty much alone. These engineered viruses are the basis for the cancer treatments now being researched by pharmaceutical companies and universities.
In an ongoing study at Duke University that was highly publicized in March by “60 Minutes,” modified polio virus is being injected into the brains of patients with a highly lethal form of brain cancer called glioblastoma.
Dr. Darell Bigner, director of the Preston Robert Tisch Brain Tumor Center at Duke, said in a video on the website that the “response in the first few patients treated has been truly remarkable” and this is “one of the most promising new treatments for glioblastoma multiforme, I’ve seen in my 40-plus years of research in the field.”
The first two patients in the trial are now cancer-free. This is unheard of with glioblastoma where tumors are expected to double in size every two to three weeks, according to one of the doctors interviewed on “60 Minutes.”
But the polio treatment is not being harkened as a cure just yet. Around half of patients in the phase 1 trial have died, and at least one experienced a severe immune reaction to a high dose of polio.
In other news, St. Luke’s Cancer Center in Pennsylvania is conducting a phase 2 trial using herpes simplex virus to treat highly advanced melanoma, and a Scotland-based company, VIRTTU Biologics, is also testing herpes’s potential to treat a number of cancers.
So, just as we’ve come to understand that a thriving colony of “good” bacteria in our guts is crucial to our well-being, we’re also going to have to give viruses a bit more appreciation for what they can do to keep us well.