title: Reduced expression of the claudin-7 gene correlates with venous invasion and liver metastasis in colorectal cancer.
abstract: Claudins, members of a large family of adherent junction proteins, regulate the integrity and function of tight junctions and influence tumorigenesis. Studies have suggested that altered levels of different claudins are related to carcinoma-cell invasion and disease progression. This study examined the relationship between the relative expression of claudin genes and clinicopathological factors, especially invasion and metastasis, in patients with colorectal cancer. We studied surgical specimens of cancer tissue and adjacent normal mucosa from 205 patients with untreated colorectal carcinoma. The relative expression levels of claudin-1, -3, -4 and -7 mRNA in cancer and in normal adjacent mucosa were measured by quantitative real-time, reverse-transcription polymerase chain reaction. The relative expression levels of the claudin-1, -3 and -4 genes were higher in cancer than in normal adjacent mucosa, whereas the relative expression of the claudin-7 gene was similar. An analysis of the relationship between the clinicopathological features and gene expression showed that reduced expression of claudin-7 correlated with venous invasion and liver metastasis. There was also a correlation between claudin-3 and -4 gene expression. Our results suggested that a reduced expression of the claudin-7 gene might lead to venous invasion and liver metastasis in colorectal cancer. Reduced expression of the claudin-7 gene may thus be a useful predictor of liver metastasis in patients with colorectal cancer.
authors: Gastroenterological Center, Yokohama City University Medical Center, Kanagawa-ken 232-0024, Japan. ohshimatakashi@yahoo.co.jp
authors: Takashi
authors: T
authors: Oshima
authors: Chikara
authors: C
authors: Kunisaki
authors: Kazue
authors: K
authors: Yoshihara
authors: Roppei
authors: R
authors: Yamada
authors: Naoto
authors: N
authors: Yamamoto
authors: Tsutomu
authors: T
authors: Sato
authors: Hirochika
authors: H
authors: Makino
authors: Shigeru
authors: S
authors: Yamagishi
authors: Yasuhiko
authors: Y
authors: Nagano
authors: Shoich
authors: S
authors: Fujii
authors: Manabu
authors: M
authors: Shiozawa
authors: Makoto
authors: M
authors: Akaike
authors: Nobuyuki
authors: N
authors: Wada
authors: Yasushi
authors: Y
authors: Rino
authors: Munetaka
authors: M
authors: Masuda
authors: Katsuaki
authors: K
authors: Tanaka
authors: Toshio
authors: T
authors: Imada
mesh_terms: D000328:Adult; D000368:Aged; D062445:Claudin-1; D062465:Claudin-3; D062506:Claudin-4; D057167:Claudins; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D012333:RNA, Messenger / Q000032:analysis; D014680:Veins / Q000473:pathology
chemical_list: C568108:CLDN1 protein, human; C568122:CLDN3 protein, human; C568157:CLDN4 protein, human; C473255:CLDN7 protein, human; D062445:Claudin-1; D062465:Claudin-3; D062506:Claudin-4; D057167:Claudins; D008565:Membrane Proteins; D012333:RNA, Messenger