P-SELECTIN EXPRESSION IN A METASTATIC PANCREATIC TUMOR-CELL LINE (SUIT-2)

The human pancreatic tumor cell line SUIT-2 was derived from a metasta tic lesion in the liver of a patient with pancreatic adenocarcinoma. S UIT-2 and clonal cell lines derived from it show spontaneous metastasi s to lung and regional lymph nodes from s.c. nude mouse xenografts and were found to express P-selectin mRNA and protein. Surface expression of P-selectin protein was increased by exposure of the pancreatic tum or cells to thrombin, oxygen radicals, and trypsin, suggesting that co mmon cellular mechanisms for regulating P-selectin surface expression exist among platelets, endothelial cells, and these pancreatic tumor c ells. The finding that P-selectin is expressed by metastatic pancreati c tumor cells demonstrates that the range of cell types that express t hese adhesion molecules is broader than believed previously.