ERAP1 and cancer: Immunopeptidome shifts due to ERAP1 inhibition have been theorized to affect the recognition of cancer cells by CD8+ T cells by either enhancing the presentation of rare antigenic epitopes (51), by inducing the presentation of novel epitopes that elicit the generation of new effector T cells (52), or by perturbing the interaction with inhibitory natural killer cell receptors (53, 54, 55).