Beta 1-6 branching of N-linked carbohydrate is associated with K-ras mutation in human colon carcinoma cell lines.
Here the K-ras genotypes of nine colon carcinoma cell lines are compared to the protein glycosylation patterns found in these cells. By a variety of methodologies utilizing lectins to probe carbohydrate structure, we find evidence that five out of six cell lines having K-ras mutations have elevated amounts of beta 1-6 branching at the trimannosyl core of N-linked carbohydrate. None of the three K-ras wild type cell lines assayed have evidence of elevated beta 1-6 branching. In five out of five cell lines examined, the amount of beta 1-6 branching correlates with the extent of cellular ras-GTP elevation and supports the hypothesis that expression of beta 1-6 branching in colon carcinoma cell lines is quantitatively linked to K-ras activation. These results are discussed in the context of the ras-signalling pathway.
Wojciechowicz
D C
DC
Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, N.Y. 10021, USA.
Park
P Y
PY
Paty
P B
PB
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry* / Q000235:genetics*; D002462:Cell Membrane / Q000378:metabolism; D003110:Colonic Neoplasms / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D011905:Genes, ras; D005838:Genotype; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics; D006031:Glycosylation; D006160:Guanosine Triphosphate / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009363:Neoplasm Proteins / Q000737:chemistry / Q000235:genetics; D010641:Phenotype; D014407:Tumor Cells, Cultured
D002241:Carbohydrates; D006023:Glycoproteins; D037102:Lectins; D009363:Neoplasm Proteins; D006160:Guanosine Triphosphate