A common asthma drug, montelukast, could be repurposed to fight hard-to-treat cancers like triple-negative breast cancer, according to early research from Northwestern University.
The study, published in Nature Cancer, reveals that tumor cells can hijack a protein called CysLTR1 to turn neutrophils-immune cells that normally kill cancer-into tumor-promoting agents. Montelukast, which blocks this receptor, was shown in mice to slow tumor growth, increase survival, and make resistant tumors respond to immunotherapy.
Experiments with human cells confirmed the same pathway is active in people. The researchers suggest CysLTR1 could serve as a biomarker to predict immunotherapy resistance. Clinical trials are needed, and safety concerns, including mood-related side effects, must be addressed.