title: Role of trefoil factor 1 in gastric cancer and relationship between             trefoil factor 1 and gastrokine 1.
abstract: Trefoil factor 1 (TFF1) is a small cysteine-rich secreted protein which             is principally expressed in the superficial cells of gastric mucosa. In gastric             cancer, TFF1 is downregulated and plays an important role. Gastrokine 1 (GKN1)             is a secreted protein with similar expression and biological functions to TFF1.             This study aimed to determine the expression and biological functions of TFF1             and the relationships between TFF1 and GKN1 in gastric cancer. RT-PCR and immunohistochemistry             were performed to detect TFF1 expression in gastric cancer cell lines and tissues.             The transfected and co-transfected AGS cells which stably expressed TFF1 or both             TFF1 and GKN1 were generated. Phenotypic changes such as cell viability, apoptosis             and cell cycle modulation were assayed in the transfected cells. We found that             TFF1 expression was significantly downregulated or lost in gastric cancer cell             lines, gastric dysplasia and cancer. Restoration of TFF1 expression in AGS cells             suppressed tumor cell viability and arrested AGS cells in the G1-S transition             phase after olomoucine treatment. However, TFF1 was unable to induce cell apoptosis.             In co-transfected cells, we found that TFF1 and GKN1 did not directly interact             at the protein level. GKN1 was unable to cooperate with TFF1 on cell viability             suppression, cell apoptosis and differentiation. Together, these results indicate             that TFF1 expression is significantly downregulated in gastric cancer. TFF1 inhibited             cell proliferation by delaying G1-S phase transition but not by inducing apoptosis.             TFF1 may not interact or cooperate with GKN1 at the protein and functional level.
authors: Department of Gastroenterology, Tumor Tissue Bank, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, PR China.
authors: Wei
authors: W
authors: Mao
authors: Jie
authors: J
authors: Chen
authors: Tie-Li
authors: TL
authors: Peng
authors: Xiao-Fei
authors: XF
authors: Yin
authors: Lian-Zhou
authors: LZ
authors: Chen
authors: Min-Hu
authors: MH
authors: Chen
mesh_terms: D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000235:genetics; D016022:Case-Control Studies; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation; D008297:Male; D008875:Middle Aged; D036361:Peptide Hormones / Q000235:genetics / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C477000:GKN1 protein, human; D036361:Peptide Hormones; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins