Overexpression of MUC13 is associated with intestinal-type gastric cancer.
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.
Shimamura
Takahiro
T
Genome Science Division, University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan.
Ito
Hirotaka
H
Shibahara
Junji
J
Watanabe
Akira
A
Hippo
Yoshitaka
Y
Taniguchi
Hirokazu
H
Chen
Yongxin
Y
Kashima
Takeshi
T
Ohtomo
Toshihiko
T
Tanioka
Fumihiko
F
Iwanari
Hiroko
H
Kodama
Tatsuhiko
T
Kazui
Teruhisa
T
Sugimura
Haruhiko
H
Fukayama
Masashi
M
Aburatani
Hiroyuki
H
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
D014408:Biomarkers, Tumor; C429552:MUC13 protein, human; D009077:Mucins; D012333:RNA, Messenger