N-linked oligosaccharides and metastatic propensity in in vivo selected mouse mammary adenocarcinoma cells

Studies using metastatic variant selected in vivo from a cloned parental ce ll line demonstrate that the expression of beta 1-6 branched, N-linked carb ohydrates and sialic acid were positively associated with in vitro invasive ness and inversely associated with metastatic potential, adherence, and in vivo growth rate. These results suggest that at least within one tumor mode l, a negative association occurs between metastatic potential and beta 1-6 branched oligosaccharide expression. In these studies two metastatic varian ts, Cl-66M1 and Cl-66M2, were selected following serial in vivo passage of Cl-66, a clonal cell line obtained from a mouse mammary adenocarcinoma cell line. The parent cell line and the two metastatic variants were approximat ely equal in their adherence to fibronectin, laminin, and collagen type IV coated plastic. In contrast, both Cl-66M1 and Cl-66M2 had a significantly i ncreased ability to invade through matrigel invasion chambers and expressed significantly increased levels of beta 1-6 branched, N-linked carbohydrate s, and sialic acid compared to the clonal parental cell line, Cl-66. Furthe rmore, the in vivo tumor growth rates of these selected variants were decre ased compared to Cl-66 with the longest tumor volume doubling time observed with Cl-66M2.