More importantly, using two different antibodies recognizing endogenous levels of O-GlcNAc on proteins in β-O-glycosidic linkage to both serine and threonine, we show that the level of O-GlcNAcylation decreases in adenomas with hetero- and homozygous deletion of Fasn (Figure 1D,E). Here, FASN is linked to adenoma.