London, Nov 9 (IANS): A weight loss condition during cancer can make immunotherapies ineffective, finds a study.
The condition, known as cancer cachexia, causes loss of appetite, weight loss and wasting in most patients with cancer towards the end of their lives.
However, cachexia often starts to affect patients with certain cancers, such as pancreatic cancer, much earlier in the course of their disease.
Cancer immunotherapies involve activating a patient's immune cells to recognise and destroy cancer cells.
In the study published in the journal Cell Metabolism, the scientists have shown in mice that even at the early stages of cancer development, before cachexia is apparent, a protein released by the cancer changes the way the body, in particular the liver, processes its own nutrient stores.
"The consequences of this alteration are revealed at times of reduced food intake, where this messaging protein renders the liver incapable of generating sources of energy that the rest of the body can use," said Thomas Flint, researcher at the University of Cambridge.
"This inability to generate energy sources triggers a second messaging process in the body -- a hormonal response -- that suppresses the immune cell reaction to cancers, and causes failure of anti-cancer immunotherapies," Flint added.
"Our work suggests that a combination therapy that either involves correction of the metabolic abnormalities, or that targets the resulting hormonal response, may protect the patient's immune system and help make effective immunotherapy a reality for more patients," said Tobias Janowitz, lecturer at the University of Cambridge.