T cells are the immune system's front-line soldiers against cancer, but in the presence of tumours they frequently become exhausted and lose their potency. Scientists at the Cancer Research UK Scotland Institute and the University of Glasgow's School of Cancer Sciences, led by Professor Victoria Cowling, have identified an enzyme that sits at the heart of this problem: CMTR1, which governs how T cells produce the energy they need to fight.
The team found that CMTR1 acts on RNA to ensure the correct versions of energy-related proteins are made, proteins that in turn shape mitochondria, the structures that power the cell. When CMTR1 is absent, mitochondria fragment and break apart, leaving T cells weakened and less able to respond to threats. The findings are published in Cell Reports, under a title describing how CMTR1 directs mitochondrial dynamics during T cell activation.
The implications are practical as well as fundamental. In Scotland, around 34,800 people are diagnosed with cancer each year and around 16,400 die from the disease, and immunotherapies that harness T cells are an increasingly important part of treatment. The researchers' next step is to identify new or existing drugs that boost CMTR1 activity. The work was funded by Cancer Research UK, the European Research Council, the Medical Research Council and the Wellcome Trust.