Expression Of TFF2in Endometrial Carcinoma And Investigation On The Roles

【Background】The endometrial carcinoma(EC) is one of the three common malignant tumors infemale genital tract, which account for about20%to30%in gynaecology neoplasm,and the morbidity and case fatality rate become higher in recent year It has beenreported that the causes of endometrial carcinoma are related with estrogen, and theestrogen receptor can reflect neoplasm’s biological features which relate with thepatients’ treatment and prognosis.The research on how to diag-nose and cure theendometrial carcinoma has the actual significance to increase the survival rate ofendometrial carcinoma patients.Trefoil factors2(TFF2), as a new protective factor in gastrointestinal mucosa, hasgained more and more attention because of its roles in gastric mucosa diseases,self-protection and repair. In the recent years, TFF2has been found to have closerelation with tumor, and there have been some reports about the abnormal expression ofTFF2in gastric cancer, lung cancer, breast cancer, cervical cancer, cholangiocarcinoma， retinal neoplasms，and prostate cancer. And TFF2isa tumor suppressor in most ofcancers, thus we predict that TFF2is probably an potential target in blocking theprogress of the cancer.To investigate the roles of TFF2in endometrial carcinoma, thisresearch detected the its expression in different kinds of endometrial tissuesbyimmunohistochemistry staining, and analyzed the relationship between endometrialcancer and TFF2.Objective:To investigate the roles of TFF2in endometrial cancer and its molecular mechanismMethods:1.The immunohistochemical method (SP) was used to detect the expression levels ofTFF2among normal endometrium cases，endometrial hyperplasia cases and endometrialcarcinoma cases．2.The expression of TFF2mRNA in human endometrial carcinoma was down-regulatedand up-regulated, respectively by transfection of siRNA-TFF2and pcDNA3.1(+)-TFF2.And they were all validated by qRT-PCR.3.Protein of TFF2、Cyclin D1、Bax、Bcl-2were validated by western blot respectively aftertransfection of siRNA-TFF2and pcDNA3.1(+)-TFF2.4. The growth rates of cells with TFF2down-regulated and up-regulated were monitoredby MTT assay and the cell growth curves were plotted.5.Cell death and cell cycle were analyzed by flow cytometry.Results:1.The expression of TFF2in Normal emdometrium is85.7%（12/14）,in hyperplasiais72.7%(16/22), in endometrial cancer is57.3%（47/82）.Three groups was defined asstatistical significance.2.The small interference RNA vector of TFF2is constructed and further identified bysequencing.3.Transfection of siRNA-TFF2markedly reduced the mRNA and transfection ofpcDNA3.1(+)-TFF2elevated the mRNA. 4. pcDNA3.1(+)-TFF2transfection markedly enhanced TFF2protein, also enhancedBax/Bcl-2expression and reduced Cyclin D1expression (p<0.05).5. SiRNA transfection markedly reduced TFF2protein, also reduced Bax/Bcl-2expression and enhanced Cyclin D1expression (p<0.05).6.Overexpression of TFF2by transfection of pcDNA3.1(+)-TFF2inhibited cell growthand induced cell apoptosis. Downregulation of TFF2could be associated withinhibition of tumor growth and regulation of tumor cell apoptosis.7. Overexpression of TFF2to the increased percentage of cells in G1phase and reducedthe percentage of cells in S phase.Downregulation of TFF2by siRNA led to the reducedpercentage of cells in G1phase and increased the percentage of cells in S phaseconclusions;Conclusions:1. Immunochemistry staining suggested TFF2was down-regulated in endometrialcarcinoma and its precancerous lesions indicating TFF2could be suppressor ofendometrial carcinoma. Downregulation of TFF2could be associated with inhibition oftumor growth and regulation of tumor cell apoptosis to promote carcinogenesis ofendometrial cells.2. TFF2via regulation of Cyclin D1、Bax、Bcl-2expression involved cell cycle andapoptosis.3. Overexpression and Downregulation of TFF2in endometrial carcinoma cell and theresults of cell biology were consistent with immunochemistry and indicated that TFF2is involved in the carcinogenesis of endometrial carcinoma and could be a suppressorof endometrial carcinoma. Loss of TFF2expression could be an early event duringcarcinogenesis of endometrial carcinoma.TFF2could be a promising candidatebiomarker or therapeutic target for endometrial carcinoma.