For example, O-GlcNAc-modified proteins are involved in cancer-relevant processes such as transcriptional regulation, cell proliferation and the cell cycle.10 The activity of many oncogenic factors, including c-Myc,11 β-catenin,12 p5313 and FoxM1,14 is regulated by direct O-GlcNAcylation. This evidence concerns the gene FOXM1 and cancer.