Peanut agglutinin inhibits proliferation of cultured breast cancer cells.

Cultured breast cancer cells express on their surface glycoproteins which are recognized by the peanut lectin (PNA). The proliferation of these cells (ZR-75.1 and 734-B) was inhibited by PNA. A mammary carcinoma cell line (BT-20) which does not react with PNA was not affected by this lectin. The combination of PNA with either retinoic acid or 4-hydroxy-tamoxifen led to an additive amplification of the antiproliferative activity. Also interferon-gamma showed in combination with PNA an improved growth-inhibitory action.