title: G protein gamma 7 expression as a new clinicopathological marker in patients with intrahepatic cholangiocarcinoma.
abstract: OBJECTIVE
  The signal alterations mediated by small G proteins such as Ras, Rho, and Rac have been reported in several cancers. The human G protein gamma 7 (G-gamma 7) gene, which is down-regulated in various digestive organ cancers, was recently identified and cloned. Thus, the G-gamma 7-coupled heterotrimeric G proteins may also contribute to carcinogenesis in human cancers.
  
  
  METHODS
  University hospital and medical institute of bioregulation.
  
  
  METHODS
  The clinicopathological significance of G-gamma 7 expression in 18 patients with intrahepatic cholangiocarcinoma (IHCC) was examined. The tumor-nontumor ratio of G-gamma 7 expression was determined using reverse transcription polymerase chain reaction analysis. To visualize the localization of G-gamma 7, an immunohistochemical study was performed.
  
  
  METHODS
  Clinicopathological significance of G-gamma 7 expression in human IHCC.
  
  
  RESULTS
  Expression of G-gamma 7 messenger RNA was lower in tumor tissue than in the corresponding nontumor tissue in 17 (94%) of 18 patients with IHCC. The mean tumor-nontumor ratio was 0.54. Eleven patients with tumor-nontumor ratios less than 0.5 showed significantly poorer differentiated IHCC than 7 with tumor-nontumor ratios of 0.5 and greater (P<.01). Decreased expression of G-gamma 7 protein in the carcinoma tissue, especially in the poorly differentiated IHCC tissue, was confirmed using immunohistochemical staining.
  
  
  CONCLUSIONS
  Reduced expression of G-gamma 7 is associated with the histological grade of IHCC and may therefore prove to be a useful marker for predicting the biological aggressiveness of human IHCC.
authors.affiliation: Department of Surgery, Medical Institute of Bioregulation, Kyushu University, 4546 Tsurumibaru, Beppu 874-0838, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Utsunomiya
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Inoue
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Taguchi
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Shimada
authors.forename: Keizo
authors.initials: K
authors.lastname: Sugimachi
authors.forename: Masaki
authors.initials: M
authors.lastname: Mori
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000378:metabolism* / Q000473:pathology; D001653:Bile Ducts, Intrahepatic; D016009:Chi-Square Distribution; D018281:Cholangiocarcinoma / Q000378:metabolism* / Q000473:pathology; D015536:Down-Regulation; D005260:Female; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D020962:Heterotrimeric GTP-Binding Proteins