The role of Thomsen-Friedenreich antigen in adhesion of human breast and prostate cancer cells to the endothelium

Interactions of metastatic cancer cells with vasculatory endothelium are cr itical during early stages of cancer metastasis, Understanding the molecula r underpinnings of these interactions is essential for the development of n ew efficacious cancer therapies. Here we demonstrate that cancer-associated carbohydrate T antigen plays a leading role in docking breast and prostate cancer cells onto endothelium by specifically interacting with endothelium -expressed beta -galactoside-binding protein, galectin-3. Importantly, T an tigen-bearing glycoproteins are also capable of mobilizing galectin-3 to th e surface of endothelial cells, thus priming them for harboring metastatic cancer cells. The T antigen-mediated, tumor-endothelial cell interactions c ould be efficiently disrupted using synthetic compounds either mimicking or masking this carbohydrate structure. High efficiency of T antigen-mimickin g and T antigen-masking inhibitors of tumor cell adhesion warrants their fu rther development into antiadhesive cancer therapeutics.