HYPOTHESIS: 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. SETTING: University hospital and medical institute of bioregulation. PATIENTS AND 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. MAIN OUTCOME MEASURE: 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.
HYPOTHESIS: 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 humancancers. SETTING: University hospital and medical institute of bioregulation. PATIENTS AND 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. MAIN OUTCOME MEASURE: 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: T Sudo; T Utsunomiya; K Mimori; H Nagahara; K Ogawa; H Inoue; S Wakiyama; H Fujita; K Shirouzu; M Mori Journal: Br J Cancer Date: 2005-05-09 Impact factor: 7.640
Authors: M Ohta; K Mimori; Y Fukuyoshi; Y Kita; K Motoyama; K Yamashita; H Ishii; H Inoue; M Mori Journal: Br J Cancer Date: 2008-01-22 Impact factor: 7.640