With respect to the O-GalNAc pathway, we observed alterations in several related glycogenes including the downregulation of GCNT4, GALNT13, GALNT16 and C1GALT1, and upregulation of ST3GAL1, ST6GALNAC4 and GAL3ST2 in Her2+ breast cancer tissue. This evidence concerns the gene GAL3ST2 and breast cancer.