Oncolytic viruses: North American scientists test new therapy to fight cancer
WATCH ABOVE: Oncolytic virus therapy is a burgeoning new field of research and Canadian researchers are at the forefront. Alan Carter reports.
TORONTO – It’s a novel approach to fighting cancer: scientists are turning to some of the world’s most feared viruses – such as polio – to attack cancer cells while leaving healthy cells relatively unharmed.
Oncolytic virus therapy is a burgeoning new field of research and Canadian researchers are at the forefront. Dr. John Bell, a senior scientist at the Ottawa Hospital Research Institute, says his team stumbled upon the idea of using viruses as weapons against cancer years ago.
“Cancer cells have a weakness when it comes to viruses and they are unable to fight infections whereas normal cells can,” Bell told Global News.
“This is the beauty of these viruses. We can give them intravenously, just like a chemotherapeutic drug. They can swim around your body and whenever they find a cancer cell then they have the chance to effectively destroy it because cancer cells are weak and unable to fight virus infections,” he explained.
The scientists say it’s like kick starting the immune system – your body detects the virus, which has attached itself to cancer cells and, ultimately, your immune system wipes out the virus, taking the cancer out too.
The research is supported by the Canadian Cancer Society. The Ottawa Hospital and University of Ottawa are studying the potential for oncolytic viruses closely.
It’s still considered experimental and isn’t available for general use, the scientists say on the OHRI website. Right now, it’s accessible only through clinical trials.
Another clinical trial is taking place at Duke University in North Carolina where researchers are relying on a modified form of the polio virus to kill a brain cancer known as gliobastoma. So far, the results from 22 patients look promising.
“The first patient was diagnosed with a brain tumour when she was 20, the gliobastoma came back nine months later when she was 21,” Dr. Annick Desjardins, an associate professor, told Global News.
“She was our first patient to receive the modified polio virus and now she’s more than three years from the treatment with the polio virus and there is absolutely no sign of tumour cells left in her brain. So she is right now in remission,” she said.
Canadian researchers have been testing out oncolytic viruses as standalone options and in collaboration with other therapies.
At the Children’s Hospital of Eastern Ontario, for example, scientists paired oncolytic viruses with drugs that target cancer-causing genes.
Their theory is that the medication could help cancer cells self-destruct under stress while the oncolytics give the dead tumour cells a fatal blow.
“Cancer is an extremely complex disease. To think it’s anything other than complex is foolish. I don’t want to say that we’ve got the answer yet, because we don’t,” Bell said.
“But what we do know is these approaches are beginning to change, the patients are responding to the clinic. We’re starting to see people who have really serious disease being treated with immune therapy have a good outcome,” he said.
*With files from Melanie Zettler
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