PPA1 and cancer: Furthermore, using the Catalogue Of Somatic Mutations In Cancer (COSMIC) database (https://cancer.sanger.ac.uk/cosmic), we found one somatic mutation each in the PP1-binding motif (R1289S) and the calcineurin-binding motif (L1142P), and also two somatic TSC2(E/K) mutations of the PP2A-B56–binding motif ([L/M/F/I]-x-x-[I/L/V]-x-E-x) in three clinical cases: E366K in rectal adenocarcinoma (https://cancer.sanger.ac.uk/cosmic/mutation/overview?id=102914022) and ovarian carcinoma (Cheasley et al, 2019), and E1583K in skin carcinoma (Starrett et al, 2020) (Fig 5F and Supplemental Data 3).