Project 170586

Protein loss, mostly from muscle, is very common in lung cancer and this affects the patients' physical function, response to treatment and quality of life. We propose that cancer patients are losing proteins because they are resistant to the normal stimuli that promote protein retention after a meal, i.e. the hormone insulin and the building blocks of proteins, amino acids. We have developed a complex metabolic test to study this and have reported that protein synthesis was not responding normally to insulin in obese, elderly, and persons with type 2 diabetes. Now we extend our test to lung cancer patients to compare those who are losing weight to those who are not. In addition, we will study whether their liver uses more amino acids to produce glucose, leaving less for muscle protein build-up, and for the synthesis of specific blood proteins with important functions. Finally, a meal rich in leucine, a particular amino acid having shown promising effects on protein retention will be tested, to see if it counteracts the resistance to insulin action. These studies could lead to design better diets and treatments aimed at preventing the loss of essential body protein and muscle in persons with lung cancer and thus improve their quality of life.

using complex metabolic testing to study protein synthesis response to leucine-rich meals in cancer cachexia