PRC1 and cancer: FBXL10 is a histone demethylase and a component of the noncanonical polycomb repressive complex 1 (PRC1).15 This protein contains a CxxC zinc finger domain that can identify unmethylated CpG islands, as well as PHD, F‐box, and leucine‐rich repeat (LRR) domains that are important for PRC1 incorporation.16, 17 FBXL10 is important in the context of cancers, driving tumorigenesis, and promoting the survival and expansion of so‐called cancer stem cells in many distinct malignancies,18, 19 but whether FBXL10 has any role in cardiomyocytes remains unknown.