Diverse expression of N-acetylglucosaminyltransferase V and complex-type ß1,6-branched N-glycans in uveal and cutaneous melanoma cells.

ABSTRACT

Although both uveal (UM) and cutaneous (CM) melanoma cells derive from the transformed melanocytes, their biology varies significantly in several aspects. Malignant transformation is frequently associated with alternations in cell glycosylation, in particular those concerning branched complex-type N-glycans. These changes occur principally in ß1,4-N-acetylglucosaminyltransferase III (GnT-III) that catalyzes the synthesis of glycans with bisected N-acetylglucosamine (GlcNAc) and ß1,6-N-acetylglucosaminyltransferase V (GnT-V) that is involved in forming ß1,6-branched antenna in complex-type glycans. We searched for the reasons of a different behavior of CM and UM cells in the expression of GnT-III and GnT-V and their oligosaccharide products. Our study showed that UM cells have more ß1,6-branched glycans than CM cells, what results from a higher expression of MGAT5 gene encoding GnT-V. The higher ß1,6-branching of glycans in UM may contribute to their higher potential to migrate on fibronectin and weaker binding to main extracellular matrix proteins, observed in our previous studies.