MGAT3 and cancer: The deletion of all five N-glycosylation sites on β4 integrin, or the introduction of bisecting GlcNAc to N-glycans on β4 integrin by N-acetylglucosaminyltransferase III (GnT-III encoded by the MGAT3 gene) overexpression, suppresses cancer cell migration and tumorigenesis [15,16], demonstrating the pivotal role of N-glycans in α6β4 integrin-mediated tumor progression.