Adhesion molecules in human pancreatic cancer.

ABSTRACT

BACKGROUND AND OBJECTIVES: Adhesion molecules are cell surface glycoproteins that are important in cell-to-cell and cell-to-extracellular matrix interactions. In the present study, we analyzed the adhesion molecules ICAM-1 (intercellular adhesion molecule-1), VCAM-1 (vascular cell adhesion molecule-1), and ELAM-1 (endothelial leukocyte adhesion molecule-1) in human pancreatic cancer. METHODS: ICAM-1, VCAM-1, and ELAM-1 were analyzed in 20 pancreatic cancer specimens and 20 normal pancreatic tissues. mRNA expression encoding ICAM-, VCAM-1, and ELAM-1 was assessed with Northern blot analysis. The distribution and localization of ICAM-1, VCAM-1, and ELAM-1 was determined in the pancreatic specimens by immunohistochemistry. RESULTS: Northern blot analysis revealed a 5.4-fold increase of ICAM-1 (P<0.01) and a 3.7-fold increase in VCAM-1 (P<0.01) mRNA expression in cancer samples in comparison with normal controls. In contrast, ELAM-1 mRNA levels did not show significant differences between the cancer and the normal tissues. Immunohistochemical analysis of cancer tissues showed strong immunostaining for ICAM-1 and VCAM-1, and faint immunostaining for ELAM-1 in the pancreatic cancer cells. Fibrotic or noncancerous pancreatic tissue adjacent to the cancer mass was devoid of any immunoreactivity for ICAM-1, ELAM-1, and VCAM-1. In contrast, the normal pancreas exhibited no immunoreactivity of ICAM-1, ELAM-1, and VCAM-1. CONCLUSIONS: Enhanced expression of ICAM-1 and VCAM-1 in human pancreatic cancers suggests a role in tumor pathogenesis. The increase of these adhesion molecules might influence the detachment of cancer cells in the primary tumor, might contribute to cancer cell migration and the spread of cancer cells to distant organs, or both.