Flow cytometric analysis of proteoglycan expression on murine tumor cells with different metastatic capacity.

Proteoglycan epitopes recognized by poly- or monoclonal antibodies were studied at the cell surface of 3LL murine tumor cell lines with different metastatic capacity. A decreased expression of heparan sulphate and chondroitin sulphate core protein epitopes was observed in the highly metastatic variant HM compared to the low metastatic counterpart LM. Interestingly, the biochemical analysis demonstrated an increased glycosaminoglycan-especially heparan sulphate-production in highly metastatic HM cells. A similar decrease in heparan sulphate proteoglycan core epitope expression was observed in the highly metastatic B16F10 cell line compared to its low metastatic variant F1. The under-representation of proteoglycan core protein epitopes at the cell surface of highly metastatic murine tumor cell lines could be interpreted by the increased glycosylation, or by the loss of those particular epitopes.