Heat therapy could improve effectiveness of cancer treatments

In collaboration with Adfero

New research suggests that gently heating cancer cells could enhance the effects of experimental new drugs, known as PARP inhibitors.

Studies have previously shown that heating tumours can improve the effectiveness of chemotherapy and radiation, but it was not previously known why.

In a new study, a team of Dutch scientists found that raising the temperature of cancer cells to between 41 and 42 degrees Celsius (106 to 109 degrees Fahrenheit) blocks a key molecule used to repair DNA damage.

When heat is used in combination with PARP inhibitors, which also prevent DNA damage repair, the DNA in the cancer cells becomes so damaged that they stop growing and die.

Fragments of tumours were injected into the hind legs of rats, some of which were then heated to 42 degrees Celsius for a period of 1.5 hours.

Experiments showed that heat is able to breakdown a protein called BRCA2, which is used to repair cell DNA. Cells that were heated were found to be more susceptible to radiation and chemical-based cancer treatments, as well PARP inhibitors that target another protein involved in DNA repair.

The research, published in the Proceedings of the National Academy of Science, suggests that combining heat with existing treatments could boost the potency of chemotherapy or radiotherapy for treating cancer.

However, it is not yet known if these lab results can be replicated in clinical trials with cancer patients.

Dr Steve Colebrook, clinical project leader at Cancer Research UK's drug development office, said: "This is very interesting research with some exciting implications.

"It's at an early stage but if further research shows heat therapy could be used in this way, promising drugs like PARP inhibitors - or indeed any other therapy which prevents cells repairing their DNA damage - could be used to treat a wider group of patients.

"Heat therapy is already being used experimentally in the clinic in cancer treatment but research would need to prove this would work in practice - and whether it would be a valid approach for tumours in hard-to-reach locations."

Blog link:
http://scienceblog.cancerresearchuk.org/2011/05/10/turning-up-the-heat-on-cancer/

Paper link:
http://www.pnas.org/content/early/2011/05/02/1101053108.abstract