Following the 2018 Nobel Prize for Medicine, global attention is now more than ever turned toward the promise of immunotherapy in oncology. An international team’s work has shed new light on a molecule called TIM-3 that might play a key role in the regulation of the immune response. Scientists and physicians from the Research Institute of the McGill University Health Centre (RI-MUHC), the Montreal Children‘s Hospital of the MUHC (MCH-MUHC) and McGill University, in collaboration with French teams from AP-HP, Inserm, Université Paris-Descartes, Université Paris-Diderot, and the Imagine Institute at the Necker-Enfants Malades hospital, have singled out this protein as the next potential target for immunotherapy treatments in patients with cancer and other diseases.

"This study places the TIM-3 protein at the heart of immune system regulation. We could use it as a target in immunotherapies to trigger enhanced immune responses in patients with cancer and better treat them," says co-lead author of this study, Dr. Nada Jabado, who is a researcher from the Child Health and Human Development Program at the RI-MUHC and an hemato-oncologist at MCH-MUHC.

Researchers found that when the TIM-3 protein is suppressed or inactive, the immune system becomes completely “unleashed” and T cells are uncontrollably over-activated, resulting in a rare form of lymphoma (a form of cancer that starts in the lymphocytes) called subcutaneous panniculitis T lymphoma (LTSCP).

The team of researchers has identified two founder mutations at the origin of this syndrome, which act directly on the TIM-3 protein, preventing it from expressing itself on the surface of the lymphocytes and attacking the cancer cells. They also found that this form of lymphoma associated with over-activation of the immune response was more widespread than they first thought.

These results, which led researchers to consider this form of lymphoma as a new genetic disease, are being published in the journal Nature Genetics on Monday, October 29.