⚕️ Cancer: the regained power of our natural killer cells

Scientists have developed a strategy to enhance the anticancer power of natural killer cells, which are part of the immune system's first line of defense. Capable of detecting and destroying cancer cells, natural killer cells are often stopped in their tracks by the protective barrier erected by tumors, leaving cancer free to spread.

A research team from the Rosalind and Morris Goodman Cancer Institute at McGill University, in collaboration with the Research Institute of the McGill University Health Centre, discovered that suppressing two proteins allows natural killer cells to overcome this obstacle and regain their anticancer power.


This approach, implemented in preclinical trials, led to the effective elimination of human cancer cells from several hard-to-treat tumor types — including leukemia, glioblastoma, kidney cancer, and triple-negative breast cancer — and also significantly slowed tumor growth in animal models.

"Our approach is particularly promising for patients who have failed standard treatments and, consequently, have very few options," says lead author Michel L. Tremblay, James McGill Distinguished Professor in the Department of Biochemistry at McGill University and researcher at the Rosalind and Morris Goodman Cancer Institute.

A safe and scalable approach

Gene editing, commonly used in cancer immunotherapy, alters cells permanently, increasing the risk of adverse effects. The new approach instead uses small-molecule drugs that temporarily boost natural killer cell activity, without causing permanent and difficult-to-control modifications.

According to the scientists, this therapeutic strategy could also overcome the practical obstacles that have hindered the large-scale use of cell therapies.

Natural killer cells from umbilical cord blood donations, isolated at the Cell Therapy Laboratory led by Pierre Laneuville and Linda Peltier at the Research Institute of the McGill University Health Centre, were cultured and banked for treating many patients. Unlike many current immunotherapies, which must be custom-prepared from each patient's cells — a process that can take several weeks — these natural killer cells are ready to use.

"With this approach, immunotherapy could become faster, safer, and more affordable," says Chu-Han Feng, researcher at the Rosalind and Morris Goodman Cancer Institute. "It bypasses the complex process of customizing cells and uses easily accessible drugs to reversibly enhance the antitumor activity of natural killer cells."

Acute myeloid leukemia, an aggressive blood cancer, is among the first cancers the team plans to target in future clinical trials, which are currently awaiting funding and regulatory approval.