Lectin-resistant variants of mouse Lewis lung carcinoma cells. I. Selection and in vivo properties.

The availability of lectin-resistant cell lines with altered carbohydrate moieties in cell surface glycoproteins and glycolipids has greatly facilitated study of the involvement of cellular glycoconjugates in tumor growth and metastasis. We present here a new animal model for metastasis study based on mouse Lewis lung carcinoma LL2 in vitro cell line. From this line, five lectin-resistant variant sublines were selected with the following lectins: wheat germ agglutinin (WGAR), Ricinus communis agglutinin II (RCA IIR) and Aleuria aurantia agglutinin (AAAR). The correlation of the lectin resistance with their in vitro and in vivo growth properties, and especially lung colonizing ability, were investigated. Three WGAR variants with well-preserved tumorigenicity revealed reduced metastatic ability, both spontaneous, after subcutaneous (s.c.) administration and experimental, after intravenous (i.v.) administration. The RCA IIR variant also possessed reduced spontaneous and experimental metastatic ability, but exhibited higher growth rate of local s.c. tumors. The AAAR variant possessed reduced spontaneous metastatic ability but its ability to colonize the lungs after i.v. administration was five-fold higher than that of the parent LL2 line, whereas its tumorigenicity remained unchanged. The relative differences among WGAR variants and parent LL2 line, concerning their experimental metastatic ability, remained similar in cyclophosphamide-modified mice to those in normal recipients.