Overexpression of GALNT14, which initiates the O-glycosylation of mucin substrates Muc2, Muc5Ac, Muc7 and Muc13, activates the invasion and migration of breast cancer cells by up-regulating MMP-2VEGF, TGF-β, N-cadherin, vimentin and down-regulating E-cad [92]. This evidence concerns the gene MUC5AC and breast cancer.