Differences in lectin binding in tissue sections of human and murine malignant tumors and their metastases

Lectin binding to tumor cells in tissue sections of 16 nonmetastatic and 24 metastatic human adenocarcinomas and 5 nonmetastatic and 5 metastatic murine Lewis lung carcinomas (LLCs) was assessed with an avidin-biotin peroxidase technique. In human tumors, Ulex europaeus agglutinin I (UEA I) showed no binding; whereas concanavalin A (Con A), Ricinus communis agglutinin I (RCA I), wheat germ agglutinin (WGA), soybean agglutinin (SBA), and Dolichos biflorus agglutinin (DBA) bound equally to primaries and metastases. However, peanut agglutinin (PNA) bound to less than 5% of cells in 37 of 40 primaries but to greater than 50% of cells in 18 of 24 metastases. In LLC tumors, UEA I and DBA showed no binding; whereas Con A, RCA I, and WGA bound equally to primaries and metastases. SBA bound to greater than 50% of cells in 5 metastases but not to the 5 primaries. There was less than 5% binding of PNA to 10 primary murine tumors after neuraminidase pretreatment of tissue sections but greater than 50% binding in 3 of 5 metastases. These studies indicate, in both human adenocarcinomas and an experimental tumor system, that most tumor cells which metastasize show preferential binding of PNA and SBA.