Cancer cells face new foe
AUSTRALIAN researchers have found a way to stop cancer cells becoming resistant to treatment in a major breakthrough that could extend the lives of patients.
When researchers blocked the resistance process in an experimental model of pancreatic cancer in mice, they were able to reduce cancer regrowth by 60 per cent, compared with using a cancer drug alone. The study used drugs already approved for use by people, and clinical trials could begin in the next year.
The research team, led by Garvan Institute professor David Thomas, found stressed cancer cells made deliberate mistakes when copying their DNA in an attempt to survive the effect of cancer drugs.
It is similar to the process in which bacteria become resistant to antibiotics. Eventually, this process produces mutated cells that no longer respond to the drugs being used to control the cancer, allowing it to start growing again.
But the study found that by combining cancer treatments with a drug called a PARP inhibitor, the resistance could be blocked, making cancer treatments more effective.
“The beauty of this idea is you are taking a drug you know works for a short time, and finding a way of deepening and extending the response,” Prof Thomas said.
The findings could have implications for the hundreds of thousands affected by cancer drug resistance each year — but researchers need $800,000 to extend the investigation.
This survival tactic was revealed in a broad range of cancers, including melanoma, pancreatic cancer, sarcoma and breast cancer. It has long been known cancer cells accumulate genetic variations that allow them to evade treatment. But how this happens — and whether the process could be targeted to improve cancer treatment — has been elusive, Prof Thomas said.
Resistance to treatment is the major issue facing patients with advanced cancers and, while most treatments work for a while, eventually the cancer outsmarts them and new treatments have to be found.
About one in three people who die from cancer die when treatments fail to stop their cancer spreading, so the “cutting edge” find has big implications, Cancer Council chief executive Sanchia Aranda, said. “Addressing treatment resistance is one of the next frontiers of managing people with advanced cancer,” Prof Aranda said.