Mucin-type O-glycosylation is catalyzed by enzymes in the N-acetylgalactosaminyltransferase (GALNT) family, including GALNT14. Clinical data have shown that GALNT14 is highly expressed in various human cancers, such as breast cancer (Huanna et al., 2015) and hepatocellular carcinoma (Lin et al., 2014), and plays an important role in regulating malignant characteristics, as is exemplified by an increased expression of some mesenchymal markers N-cadherin and vimentin and TGF-β (Table 2) (Huanna et al., 2015). Here, TGFB1 is linked to breast cancer.