O-sialoglycoprotein endopeptidase (OSGEP), catalysing the tRNA modification N6-threonylcarbamoyladenosine (t6A), drives protein homeostasis in cancer cells to maintain T-cell exclusion and prevent anti-tumour immune response.

Through in-depth cellular and molecular profiling of mice and human tumours, the authors identify the mechanisms by which anti-inflammatory drugs targeting the COX-2/PGE2/EP2-4 axis rapidly alter the tumour immune landscape to enhance the response to immune checkpoint inhibition.