By MEGAN SCUDELLARI

May 9, 2011

Local hyperthermia boosts the effectiveness of cancer treatments by preventing DNA repair in tumor cells.

Hyperthermia is occasionally used to augment the efficacy of certain cancer therapies, but how heat helps has been a mystery. Now, researchers have uncovered the details of one likely mechanism — heating a tumor inhibits homologous recombination, a DNA repair system, so cancer cells cannot mend DNA damaged by radiation or chemotherapy.

The finding, published today in Proceedings of the National Academy of Sciences, suggests that the addition of heat may expand the use of promising cancer drugs targeted to cells defective in homologous recombination.

“The findings reported are very important,” said George Iliakis, who studies cellular responses to DNA damage at the University of Duisburg-Essen Medical School and was not involved in the research, in an email to The Scientist. If confirmed with future tests, he added, “they promise to revive the field of hyperthermic oncology — a field of oncology that has been nearly forgotten.”

Hyperthermia used in conjunction with radiation treatments made a splash in the 1970s and 1980s, appearing to somehow inhibit tumor cells’ ability to repair its DNA and fix damage done by radiation and chemotherapy, which are designed to cause enough DNA damage to kill a cell. But subsequent clinical trials failed to demonstrate the effectiveness of the combination treatment, and over time, competing approaches stepped in to the limelight. Today, with improved instrumentation to heat defined areas of the body to desired temperatures and a recent positive phase III clinical trial, interest in the field is renewed.

Read Full Article at The Scientist