Human colon cancer cell lines permanently expressing alpha 2,6-sialylated sugar chains by transfection with rat beta-galactoside alpha 2,6 sialyltransferase cDNA

A role of alpha 2,6-linked sialic acid in the development of;an invasive phenotype in colon cancer has been suggested by several observations but never conclusively demonstrated. An experimental model to clarify this issue was established by the creation and characterization of a bank of cell lines that differ mainly, if not exclusively, in the degree of alpha 2,6-sialylation. Human colon cancer cell lines SW48 and SW948, normally unable to elaborate the alpha 2,6-sialyl linkage, were transfected with the beta-galactoside alpha 2,6-sialyltransferase (alpha 2,6ST) cDNA driven by the cytomegaloviral promoter and screened for cell surface alpha 2,6-sialylated sugar chains using fluorescein isothiocyanate-conjugated Sambucus nigra agglutinin (SNA-FITC). A panel of SNA-FITC-positive clones was established that expresses alpha 2,6ST activity to varying degrees. Only the SNA-FITC-positive recombinants express the 1.2 Kb mRNA predicted to be generated from the transfected sequence. No 4.3-4.7 Kb transcripts that are indicative of transcription from the native alpha 2,6St gene were detected.(C) 1995 Academic Press, Inc.