A flow cytometric analysis of the expression of adhesion molecules on human renal cell carcinoma cells with different metastatic potentials.

OBJECTIVES

We investigated the relationship between the metastatic potential and the surface expression of adhesion molecules on human renal cell carcinoma (HRCC) cells.

METHODS

The metastatic potential was studied by the intravenous injection of cells from an HRCC cell line SN12C parent and its variants, SN12C-MM3, SN12C-clone2 and SN12C-clone8 into athymic Balb/c nude mice. The surface expression of adhesion molecules on these four HRCC cell lines was studied by a flow cytometric analysis.

RESULTS

Of the four cell lines, SN12C-MM3 had the highest ability to produce pulmonary metastatic nodules. In contrast, the SN12C parent, SN12C-clone2 and SN12C-clone8 produced either few or no pulmonary metastatic nodules. A flow cytometric analysis revealed that SN12C-MM3 showed a strong expression of sialyl Lewis X (sialyl Le(x)) carbohydrate antigen and a slightly stronger expression of CD11a (LFA-1 alpha-chain) and CD54 (ICAM-1) compared with the other three cell lines. All cell lines expressed CD29 (beta 1-integrin) and CD44 to the same extent.

CONCLUSION

Sialyl Le(x) is thought to be a ligand for the adhesion molecule called ELAM-1 (endothelial-leukocyte adhesion molecule-1, E-selectin) and mediates the interaction of leukocytes or tumor cells to endothelial cells, followed by the integrin-mediated adhesion. These data suggest that SN12C-MM3 cells may have more of a chance to adhere to endothelial cells in blood vessels and consequently shows a higher metastatic potential when injected intravenously in comparison to the other three lines.