Ganglioside antigen of DU-PAN-2 in a human pancreatic cancer

DU-PAN-2 reactive gangliosides were isolated from the tumor of a patient with pancreatic cancer (duct cell carcinoma, moderately differentiated adenocarcinoma), having a negative Lewis blood phenotype, and were analyzed by means of TLC-immunostaining, enzyme-linked immunosorbent assay (ELISA), permethylation study, 1H NMR spectroscopy and fast atom bombardment mass spectrometry. The structures of the gangliosides were found to be NeuAc alpha 2-3Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1'Cer, containing normal and hydroxy fatty acids. By TLC-immunostaining and ELISA with chemically synthesized gangliosides, DU-PAN-2 was demonstrated to react strongly with IV3 alpha NeuAc-Lc4Cer, weakly with IV3 alpha NeuAc-nLc4Cer, and moderately with IV6 alpha NeuAc-Lc4Cer and IV6 alpha NeuAc-nLc4Cer. Thus it was concluded that the DU-PAN-2 reactive ganglioside in the tumor is IV3 alpha NeuAc-Lc4Cer and that DU-PAN-2 has a rather broad specificity.