COX-2 inhibitors may reverse IDO1-mediated immunosuppression in some cancers

(American Association for Cancer Research) In preclinical studies, tumors that consitutively expressed the protein indoleamine 2,3-dioxygenase (IDO1) responded to the cyclooxygenase-2 (COX-2) inhibitor celecoxib (Celebrex) and had improved infiltration of certain subsets of T cells, making them more likely to respond to anti-PD1 therapies.