A soluble form of K-sam/FGFR2 protein in the culture medium of human gastric cancer cells.
K-SAM/FGFR2 gene encodes a receptor tyrosine kinase which belongs to the fibroblast growth factor receptor family and is amplified and overexpressed in KATO-III gastric cancer cells. To characterize K-sam proteins in cancer cells, anti-K-sam rabbit polyclonal antibody PK1-2 was raised and used for the immunoprecipitation analysis. 135, 125, and 110-kDa transmembrane proteins were detected in KATO-III cell lysate, while a soluble truncated 85-kDa K-sam protein was found in the conditioned medium. The molecular size of the soluble K-sam protein does not match with those predicted from the secreted forms of the K-sam cDNA which have been cloned so far. The soluble K-sam protein was highly N-glycosylated like the transmembrane versions, and N-glycosylation appeared to be necessary for its release.
Kishi
T
T
Genetics Division, National Cancer Center Research Institute, Tokyo, Japan.
Yoshida
T
T
Terada
M
M
D016475:3T3 Cells; D000818:Animals; D017077:Culture Media, Conditioned; D006801:Humans; D051379:Mice; D011233:Precipitin Tests; D020794:Receptor Protein-Tyrosine Kinases / Q000737:chemistry / Q000378:metabolism*; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000737:chemistry / Q000378:metabolism*; D012995:Solubility; D013274:Stomach Neoplasms / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D017077:Culture Media, Conditioned; D017468:Receptors, Fibroblast Growth Factor; C496353:FGFR2 protein, human; C496354:Fgfr2 protein, mouse; D020794:Receptor Protein-Tyrosine Kinases; D051497:Receptor, Fibroblast Growth Factor, Type 2