Cell surface immunophenotype and gelatinase activity of the human breast carcinoma cell line (MCF-7/6) with functionally defective E-cadherin

Expression of differentiation and adhesion cell surface antigens (Lewis(X) - CD15, CD44, syndecan 1 - CD138 and basigin/EMMPRIN - CD147) were determin ed on the cell surface of human breast carcinoma MCF7 cells in vitro with t he aid of flow cytometry and compared with that of MCF-7/6 cells, with func tionally defective E-cadherin system and increased biological aggressivenes s. The major cell surface alterations in MCF-7/6 cells compared with the pa rental MCF-7 cell line were a markedly increased CD15 (Lewis(X)) and CD44 a ntigen cell surface expression on MCF-7/6 cells. There were no major differ ences between parental MCF-7 and MCF-7/6 cells in cell surface syndecan 1,b asigin/EMMPRIN, E-cadherin and high affinity non-integrin laminin receptor expression. The constitutive cell surface gelatinase A and B activities wer e absent on MCF-7 and faint in MCF-7/6 cells. Both phorbol ester TPA and tu mor necrosis factor TNF-alpha induced a marked up-regulation of gelatinase B only in MCF-7/6 cells. No marked differences in penetration of MCF-7 vs. MCF-7/6 cells into collagen/fibroblast matrix in vitro were observed. The i ncreased expression of CD15 (Lewis(X)), CD44 antigen and TNF-alpha-inducibl e gelatinase B on MCF-7/6 cells may represent auxiliary factors contributin g to the increased biological aggressiveness of MCF-7/6 cells.