Common glycoproteins expressing polylactosamine-type glycans on matched patient primary and metastatic melanoma cells show different glycan profiles.

Recently, we reported comparative analysis of glycoproteins which express cancer-specific N-glycans on various cancer cells and identified 24 glycoproteins having polylactosamine (polyLacNAc)-type N-glycans that are abundantly present in malignant cells [Mitsui et al., J. Pharm. Biomed. Anal. 2012, 70, 718−726]. In the present study, we applied the technique to comparative studies on common glycoproteins present in the matched patient primary and metastatic melanoma cell lines. Metastatic melanoma cells (WM266-4) contained a large amount of polyLacNAc-type N-glycans in comparison with primary melanoma cells (WM115). To identify the glycoproteins expressing these N-glycans, glycopeptides having polyLacNAc-type N-glycans were captured by a Datura stramonium agglutinin (DSA)-immobilized agarose column. The captured glycopeptides were analyzed by LC/MS after removing N-glycans, and some glycoproteins such as basigin, lysosome-associated membrane protein-1 (LAMP-1), and chondroitin sulfate proteoglycan 4 (CSPG...