title: Elevated expression level of 60-kDa subunit of tRNA-guanine transglycosylase in colon cancer.
abstract: tRNA-guanine transglycosylase (TGT) is an enzyme which synthesizes a modified nucleoside, queuosine, by exchanging the base moiety of guanosine for queuine in tRNA. We have reported that the expression level of the 60-kDa subunit of TGT (TGT60kD) is elevated in leukemic cells, however, there is no other report on the expression of TGT60kD in cancer cells. The expression levels of the TGT60kD protein are elevated in four of the five colon cancer cell lines and 83% of colon cancer tissues compared with normal tissues. The expression levels of the TGT60kD protein decreased in two colon cancer cell lines, after cell differentiation was induced. A marked positive staining of cancer cells in colon tissues was observed, and the subcellular staining pattern was mainly cytosolic. These data suggest that the role of TGT60kD in colon carcinogenesis.
authors.affiliation: Department of Pharmaceutical Sciences, Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan. ishiwata@phar.kindai.ac.jp
authors.forename: Shunji
authors.initials: S
authors.lastname: Ishiwata
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Ozawa
authors.forename: Jun
authors.initials: J
authors.lastname: Katayama
authors.forename: Shuko
authors.initials: S
authors.lastname: Kaneko
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shindo
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Tomioka
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ishiwata
authors.forename: Goro
authors.initials: G
authors.lastname: Asano
authors.forename: Shigeo
authors.initials: S
authors.lastname: Ikegawa
authors.forename: Michinao
authors.initials: M
authors.lastname: Mizugaki
mesh_terms: D002277:Carcinoma / Q000201:enzymology* / Q000503:physiopathology*; D002454:Cell Differentiation; D002471:Cell Transformation, Neoplastic; D003110:Colonic Neoplasms / Q000201:enzymology* / Q000503:physiopathology*; D020869:Gene Expression Profiling; D006801:Humans; D010430:Pentosyltransferases / Q000096:biosynthesis*; D014407:Tumor Cells, Cultured
chemical_list: D010430:Pentosyltransferases; C020837:queuine tRNA-ribosyltransferase