Indeed, while some studies argue for a role of O-GlcNAcylation in the regulation of EZH2 stability and catalytic activity [29,30,31], others propose that the glycosylation rather regulates EZH2 recruitment to some of its target genes such as FOXC1 in breast cancer cells [32] or IL-15 in muscle [33]. Here, FOXC1 is linked to breast carcinoma.