Approximately half of cancer patients become wasted, losing a profound amount of muscles and fat, increasing the risk of death. Many become so frail, they cannot safely undergo potentially life-saving treatments.
Now researchers have discovered a molecule that appears to be responsible for this condition, known as cachexia. The finding by researchers at Dana-Farber Cancer Institute in Boston opens the possibility that the condition can be reversed.
In an advanced online edition of the journal Nature, the scientists describe how a protein called PTHrP, released by many tumors, switches on a heat-producing process in fatty tissues, resulting in unhealthy weight loss.
In both test tube experiments and research with mice with lung tumors, an antibody that actively blocks PTHrP almost completely prevented the loss of muscle mass and improved muscle function in treated animals.
Researchers do not know if PTHrP is responsible for wasting in all types of cancers, so that is one of the questions that must be answered before human trials of the antibody could begin.