The relationship between blood group-related antigen A and cell proliferation was studied in a pancreatic carcinoma cell line (PGHAM-1) induced by N-nitrosobis (2-oxopropyl) amine (BOP) in hamsters. In vitro, the cell proliferation of PGHAM-1 was inhibited in a culture medium with an added monoclonal antibody (MoAb) against blood group-related antigen A depending on its concentration. In in vivo experiments, immunohistochemical double staining was performed using MoAb against blood group-related antigen A and bromodeoxyuridine (BrdU) in pancreatic carcinomas by intrapancreatic transplantation of PGHAM-1.
Antigen A was expressed in the cell membrane and cytoplasm of PGHAM-1 cells. The BrdU labeling index (LI) in lesions with strong expression of MoAb A (≥50%) was 27.4±5.00, whereas the BrdU LI in lesions with weak expression of MoAb A (≤10%) was 11.9±2.10.
The mean LIs in strongly expressed lesions of MoAb A were higher than those in weakly expressed lesions of MoAb A (p<0.01). These results indicated that antigen A might be associated with cell proliferation in pancreatic carcinomas induced in hamsters. (J Nippon Med Sch 1997; 64: 30-38)