The Study Of G-protein γ7 Expression In Patients With Extrahepatic Cholangiocarcinoma

G proteins are heterotrimers composed of α, β and γ subunits.So far 16α, β and 12γ subunit genes have been described in mammals. The signal alterations mediated by small G-proteins such as Ras, Rho, and Rac have been reported in several cancers. Heterotrimeric G protein transduces signals across the plasma membrane from a receptor to an effector. The human G-protein γ 7 (G-γ 7) gene, which is down-regulated in various digestive organ cancers,was recently identified and cloned. Recent analys is revealed that G- y 7 lacated on human chromosome 19p13. 3. Loss of chromosone 19p13. 3 was observed frequently in several cancers, including pancreatic cancer, astrocytoma,and ovarian cancer. G-γ 7 subunits determine the functional specificity and stabilize the heterotrimetric G protein to the cellular membrane. Because G- y 7 was expressed in a variety of tissues and may regulate widely distributed signal transduction pathways, the G-γ 7-coupled heterotrimetric G-protein may also contribute to carcinogenesis in human cancers. Previous studies have revealed that G- y 7 expression was associated with the survival of various carcinoma patients,suggest ing that G-γ 7...