Researchers in Australia may have found the solution to a previously unsolved problem regarding an aggressive and deadly cancer.
The research was conducted on small-cell lung cancer, an ailment with a survival rate of only five percent within five years of diagnosis. Chemotherapy is usually an effective and many patients go into remission, but in most cases the cancer returns. Once the cancer has returned, the patients rarely survive.
For years, scientists have been unable to pin down the mechanism behind the cancer’s return. The most puzzling thing about it is that when patients go into remission, scans rarely detect even a trace of cancerous cells.
Now researchers at Monash University in Melbourne, as well as scientists in the United States, have discovered the cause of this phenomenon, an event that has far-reaching implications for treating people with this disease.
Laboratory experiments revealed that the regeneration of cancer cells could be stopped by administering a drug that blocks a type of protein called hedgehog, which plays a huge role in cell growth.
According to Neil Watkins, a professor at the Monash Institute of Medical Research, inhibiting hedgehogs may eventually be used by doctors to increase the effectiveness of chemotherapy and prevent the return of small cell lung cancer.
What we found was that… the hedgehog is very important when the cells are depleted down to a tiny population and are asked to regenerate the tumor,” said Watkins. “If you use a drug that blocks the hedgehog signalling, you can prevent small cell lung cancer cells from regenerating after chemotherapy.”
The research method used in the hedgehog experiments differ from typical cancer studies, which focus on shrinking tumors. With small cell lung cancer, doctors are unable to distinguish whether a few small but dangerous cells are still in the body.
Since hedgehog inhibiting drugs only act to keep cells from regenerating, they cannot act on existing tumors. In this way, hedgehog inhibiting drugs are more of a preventative measure than a cure.
Even still, Professor Watkins is hopeful that drug companies will carry out clinical trials on cancer patients based on his research.
“If you wanted to test what we found in people you would need to get patients who have had a complete remission following chemotherapy and then start them on a treatment to see if it prevented it from coming back,” he said. “But you wouldn’t have any immediate way of measuring if the drug worked.”
Watkins says that doctors would have to wait twelve months to be sure that the cancer hadn’t returned.
This research is good news for victims of small cell lung cancer due to asbestos exposure. It is possible that patients who successfully undergo chemotherapy of mesothelioma cancer and other cancers could eventually see its benefit as well.