Different expression of CD44, ICAM-1, and HSP60 on primary tumor and metastases of a human pancreatic carcinoma groaing in scid mice

Surface adhesion molecules play an important, but still not completely clar ified role in tumor metastasization. In this research, FAGS analysis was em ployed to analyze surface expression of CD44H, CD44v5, CD44v6, ICAM-1 and H SP60 in human pancreatic adenocarcinoma cells growing in vitro or collected ex vivo from primary tumors and lung metastases of tumor-engrafted SCID mi ce. It was found that, in metastatic cells, the standard form of CD44 (CD44 H) is down,-regulated, while a large fraction of cells express on membrane the splice variants v5/v6 and in addition, ICAM-1 and HSP60. It was also ap parent that two cell populations are present in lung metastases: a CD44(neg ) population including cells expressing CD44v5/v6, ICAM-1 and HSP60 and a p opulation of CD44(pos), CD44v5/v6(neg), ICAM-1(neg) and HSP60(neg) cells. T hese results demonstrate that, in pancreatic adenocarcinomas, metastasizati on is correlated with expression of the CD44 variants v5 and v6. Moreover, this is the first report demonstrating HSP60 surface expression on metastat ic cells.