A drug widely used to treat asthma and allergies may help fight aggressive cancers, according to a new study that uncovered how tumors hijack common white blood cells to evade immunotherapy.
At the center of the discovery is a molecule called CysLTR1, which is best known for its role in asthma and inflammation. Drugs that block it, such as montelukast (also called Singulair), have been prescribed for decades to treat asthma.
For their study, published in Nature Cancer, the research team combined experiments in mouse models, human immune cells and human tumor samples with analysis of large patient cancer datasets.
The mouse studies included models with triple-negative breast cancer, melanoma, ovarian cancer, colon cancer and prostate cancer. The scientists either genetically removed CysLTR1 or blocked it using drugs, such as montelukast.
In several mouse models, blocking the pathway slowed tumor growth, improved survival and restored response to immunotherapy. That worked even in tumors that had already stopped responding to treatment.
In analyses of human tumor samples and public cancer datasets, the scientists found more evidence that CysLTR1 plays a crucial role in promoting cancer growth. They found that patients with higher CysLTR1 activity tended to have worse survival and poorer response to immunotherapy across multiple cancer types.
Because drugs that block CysLTR1are already FDA-approved, the findings could quickly move into patient trials.
“The next steps are to confirm this mechanism in patients, identify who will benefit most, optimize how we use these drugs especially in combination with immunotherapy, and begin carefully designed clinical trials,” said senior author Bin Zhang, professor of cancer immunology at Northwestern University Feinberg School of Medicine.
Data from Northwestern University