Australian doctors said Tuesday they had found a molecule that suppresses appetite and in experiments with mice were able to turn it off by injecting an antidote.
The breakthrough by the Sydney team could help cancer patients with wasted bodies put on the weight they need to survive chemotherapy and radiotherapy.
Conversely, spurring on the MIC-1 molecule in overweight people would help them rapidly shed weight.
"It's very exciting to be able to work on a therapy that could change lives the way this will," lead researcher Herbert Herzog told The Sydney Morning Herald. "We think that a cancer patient will only have to be injected with the (MIC-1) antibody every three weeks and a person can put on a significant amount of weight in that time which would really help them."
Herzog said a large amount of MIC-1 was produced by cancers and that this was a cause of the dramatic weight loss seen in cancer patients.
Sam Breit, a member of the team, said experiments in mice showed the more advanced the cancer, the stronger the don't-eat message conveyed to the brain.
"This is a very exciting discovery because we have effectively found a new appetite pathway we didn't know existed," Breit said. "It's a breakthrough that could directly improve quality of life for many people."
He said the next step was to find a commercial sponsor and run clinical trials with humans using a synthetic MIC-1 protein.
The findings are published in the journal Nature Medicine.