ABSTRACT
ObjectiveTo analyze the status of DACH1 gene promoter methylation and explore its association with the expression of DACH1 gene promoter methylation and clinical significance of endometrium carcinoma(EC).Methods From February 2004 to August 2008,a total of 80 EC tissue samples with comprehensive surgical pathology staging were collected and used for this study.Twenty normal endometrium tissues in 2008 were abtained from the fractional curettage because of dysfunctional uterine bleeding as control.All samples were confirmed pathologically.Methylation specific PCR (MSP) was performed to detect the promoter methylation of DACH1 gene,and analyze its influence on the expression of DACH1 and the relationship between DACH1 promoter methylation and clinicopathological factors in EC.DACH1 protein expression was detected by western blot.Chi-square test and Pearson test were used for statistical analysis.ResultsThe rate of promoter methylation of DACH1 gene in the EC tissues was significantly higher than that in the normal endometrium issues (30％ vs.5％,P ＜ 0.05).There was an association between the expression of DACH1 and DACH1 gene promoter methylation ( r =- 0.30,P ＜ 0.01 ).There was statistical difference between the methylation of DACH1 and the pathological grade ( P ＜ 0.05 ) or histological type ( P ＜0.05).But DACH1 gene methylation was not related with the age,stage,myometrial invasion depth and lymphnode metastasis (P ＞ 0.05 ).Conclusions DACH1gene promoter methylaion could lead to a decrease or absence in the DACH1 expression in EC.The promoter methylation of DACH1 gene may induce the inhibition of DACH1 expression,which might be one of the mechanisms of DACH1 gene inactivation in human EC.
ABSTRACT
AIM: To investigate the hypothesis that low-molecular weight heparin (LMWH) regulates in vitro cytotrophoblast invasiveness and production of metalloproteinases-2 (MMP-2), tissue inhibitor of metalloproteinas-2 (TIMP-2). METHODS: Chorionic villi tissue of normal 6-8 weeks pregnancy was obtained. Trophoblastic cells were collected by trypsin-collagenase digestion and Percoll gradient centrifugation. The cytotrophoblastic cells were cultured for 24 h and divided into 4 groups according to the concentrations (1.0×10~2 IU/L, 1.0×10~3 IU/L or 1.0×10~4 IU/L) of LMWH adding into the medium. The contents of MMP-2 and TIMP-2 in cell culture supernatants were measured by the method of ELISA. Cytotrophoblast invasiveness was determined by Transwell chamber assay. RESULTS: With the increasing concentrations of LMWH, the invasion activity of cytotrophoblastic cells and MMP-2 secretion were increased. At concentration of 1.0×10~3IU/L, LMWH greatly enhanced cytotrophoblast invasiveness and the expression of MMP-2 (P<0.05). The levels of TIMP-2 were decreased after intervention with LMWH. At concentration of 1.0×10~3IU/L or 1.0×10~4 IU/L, LMWH induced a significant decrease in TIMP-2 expression. No significant difference between group 1×10~3IU/L and group 1.0×10~4 IU/L was observed (P>0.05). CONCLUSION: LMWH might regulate cytotrophoblast invasiveness in vitro by influencing the expression of MMP-2 and TIMP-2 in cytotrophoblastic cells.