A study published this month in Science identifies a new cellular pathway that can promote and support the growth of cancer cells. The protein kinase complex known as mTORC1 plays a key role in cellular metabolism and nutrient sensing. The mechanism involved in enabling mTORC1 activity and its recruitment to the lysosome was found to be of utmost importance to cancer cells.
The newly unearthed evidence could possibly lead to the formulation of a therapeutic approach that would inhibit this pathway in human cancer cells and help control their growth.
In healthy organisms, this pathway allows for better adaptability to different phases of nutrient availability. In simpler terms, starvation or the lack of food supply promotes catabolism—the breaking down of nutrients in order to obtain energy to function—and eating leads to anabolism—the buildup of molecules, such as proteins. The feedback loop discovered within the pathway allows it to control itself and mediate the switch from catabolism to anabolism which in turn was found to equip organisms to adapt to food availability.
The researchers as a part of this study went on to study the role of this pathway in cancer cells. What they discovered was that the over activation of this pathway, which is normally observed in some types of cancer, including renal cell carcinoma, melanoma, and pancreatic cancer, played a key role and was extremely important to promote and support the growth of cancer cells in culture and animal models.
“We demonstrated in our study that blocking the pathway resulted in reduction of tumor growth in an experimental model of human melanoma transplanted into mice. I am most excited about the future potential therapeutic applications of this discovery against cancer. Developing pharmacological treatments that interfere with this pathway might one day help stop tumor growth.” Says head scientist Dr.Andrea Ballabio, professor of molecular and human genetics at Baylor College of Medicine and Texas Children’s Hospital in Houston, and director of the Telethon Institute of Genetics and Medicine in Naples, Italy.