Up-regulation of LOX-1 expression by TNF-alpha promotes trans-endothelial migration of MDA-MB-231 breast cancer cells.

Adhesion of cancer cell to endothelial cells and the subsequent trans-endothelial migration are key steps in metastasis. However, the identities of the molecules mediating cancer cell/endothelial cell interaction are still not fully understood. In this study, we tested the hypothesis that lectin-like oxidized-low-density lipoprotein (oxLDL) receptor-1 (LOX-1), a key mediator of vascular inflammation and atherosclerosis expressed on endothelial cell surface, mediates breast cancer cell/endothelial cell interactions. We showed that up-regulation of endothelial LOX-1 by TNF-alpha promoted the adhesion and trans-endothelial migration of MDA-MB-231 breast cancer cells. Thus, endothelial LOX-1 could present a novel pathway in breast cancer metastasis.