Augmentation of UDP-GalNAc: Fucalpha1-2Gal alpha1-3 N-acetylgalactosaminyl transferase activity in nitrosamine-induced hamster pancreatic cancers.
Pancreatic cancers induced by N-nitrosobis(2-oxopropyl)amine (BOP) in hamsters produce blood group-A antigen (BG-A Ag), which is not present in the normal pancreas. To understand the neo-expression mechanism of BG-A Ag, we examined uridine diphosphate (UDP)-N-acetylgalactosamine (GalNAc): fucose (Fuc) alpha1-2 galactose (Gal) alpha1-3 GalNAc transferase (alpha1-3 GalNAc Tf) activity, the enzyme responsible for BG-A production. The specific activity of alpha1-3 GalNAc Tf in pancreatic cancers was approximately 8,000 nmole/g protein/h, whereas it was absent from the normal pancreas. Although the antrum and colon express A-Tf and BG-A Ag, the divalent cation requirements of alpha1-3 GalNAc Tf in these tissues were different from those of cancers. These results suggest that alpha1-3 GalNAc Tf is activated during BOP-induced pancreatic carcinogenesis, and that there are multiple alpha1-3 GalNAc Tf isozymes present in hamster tissues.
Hirota
M
M
Dept. of Surgery II, Kumamoto University Medical School, Kumamoto City, Japan.
Egami
H
H
Ogawa
M
M
D000818:Animals; D000951:Antigens, Neoplasm / Q000378:metabolism; D006224:Cricetinae; D005646:Fucosyl Galactose alpha-N-Acetylgalactosaminyltransferase / Q000378:metabolism*; D007150:Immunohistochemistry; D007700:Kinetics; D009602:Nitrosamines / Q000633:toxicity; D010179:Pancreas / Q000201:enzymology; D010190:Pancreatic Neoplasms / Q000139:chemically induced / Q000201:enzymology*
D000951:Antigens, Neoplasm; D009602:Nitrosamines; D005646:Fucosyl Galactose alpha-N-Acetylgalactosaminyltransferase