Over the recent decades, cancer immunotherapy has emerged as a revolutionary approach to reinvigorate host anti-tumor immunity. However, while immune checkpoint inhibitors have proven durably effective in a subset of cancer patients, many patients fail to respond or eventually relapse during or after immunotherapeutic treatment.

Amino acid-metabolizing enzymes play a crucial role in the immune escape of cancer cells by creating an immunosuppressive tumor microenvironment, both through depletion of important amino acids and accumulation of immunosuppressive metabolites. Therapeutic targeting of these enzymes may therefore restore anti-tumor immune responses and enhance the efficacy of existing cancer treatments. In our latest review published in Frontiers in Immunology (Grobben, 2024), the involvement of different amino acid-metabolizing enzymes in cancer and the anti-tumor immune response is explored, and exciting preclinical and clinical developments are highlighted.