These findings present far‐reaching implications for therapeutic targets in cancers harboring ARID2 mutations.51 The development of cancer immunotherapy has reached an important inflection point in the history of cancer therapy,52 and the correlation of a higher mutational load and a higher rate of response to immune checkpoint inhibitors has been shown.53 Such novel conceptual drugs may also be good candidates for ARID2‐mutated cancers displaying a hypermutator phenotype. Here, ARID2 is linked to cancer.