Lectin binding sites in cultured human breast cancer cells

Two estrogen-sensitive (ZR 75.1 and 734 B) and two estrogen-independent (BT 20 and Hs 578 T) human breast cancer cell lines, and one larynx carcinoma cell line (Hep. 2), were investigated immunocytochemically for the occurrence of lectin binding sites. Peroxidase-labeled peanut agglutinin (PNA) was used. PNA binding sites could be observed in estrogen-sensitive cell lines only. In ZR 75.1, the most estrogen-sensitive cell line, PNA binding sites were also observed without neuraminidase pretreatment. In our study, PNA binding is associated with the biological estrogen dependence of the tumor cells.