title: Overexpression of MUC13 is associated with intestinal-type gastric cancer.
abstract: Mucins are secreted or transmembrane glycoproteins that are expressed mainly in the digestive tract. This family of proteins has been the focus of much gastric cancer research as some transmembrane mucins are implicated in tumorigenesis and make attractive targets for cancer diagnosis and therapeutics. Mucins have also been utilized to classify gastric cancer by differentiating between gastric and intestinal phenotypes. Here we show that transmembrane mucin MUC13 is upregulated in gastric cancer. By quantitative real-time reverse transcription-polymerase chain reaction and immunoblot analysis, overexpression of MUC13 was verified in more than half of the samples examined. In immunohistochemical analysis, MUC13 staining was observed in 74 of 114 cases of gastric cancer (64.9%), predominantly in intestinal type (P < 0.001), and in 9 of 10 cases of intestinal metaplasia, precancerous lesions of intestinal-type gastric cancer, but not observed in normal gastric mucosa. Moreover, MUC13 staining patterns characteristic of histological type were identified: staining was on the apical side of tubular glands in intestinal type and on the cytoplasm in diffuse type. These results suggest that MUC13 is a good differentiation marker for gastrointestinal mucosa and that it may have a causal role that correlates with two distinct gastric tumorigenesis pathways.
authors.affiliation: Genome Science Division, University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shimamura
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Ito
authors.forename: Junji
authors.initials: J
authors.lastname: Shibahara
authors.forename: Akira
authors.initials: A
authors.lastname: Watanabe
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Hippo
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Taniguchi
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Chen
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kashima
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ohtomo
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Tanioka
authors.forename: Hiroko
authors.initials: H
authors.lastname: Iwanari
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kodama
authors.forename: Teruhisa
authors.initials: T
authors.lastname: Kazui
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Sugimura
authors.forename: Masashi
authors.initials: M
authors.lastname: Fukayama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Aburatani
mesh_terms: D014408:Biomarkers, Tumor; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007414:Intestinal Neoplasms / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009077:Mucins / Q000235:genetics* / Q000378:metabolism*; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013274:Stomach Neoplasms / Q000145:classification* / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; C429552:MUC13 protein, human; D009077:Mucins; D012333:RNA, Messenger