| Background and ObjectiveEndometrial carcinoma is a malignant disease which derives from normal epithelial,it's one of the most common malignant tumors in genital duct. The incidence of endometrial carcinoma has a tendency of increase both in the western countries and China. Though it has a better prognosis,its molecular mechanism has not exactly definite. Therefore,it is very important to explore a new therapy methods for endometrial carcinoma.Signal transducers and activators of transcription (STAT) proteins are a family of transcriptional factors first characterized for their roles in cytokine signaling. These versatile proteins contain a site for specific tyrosine phosphorylation, a modification that results in a conformational rearrangement and dimerization through phosphor tyrosine-SH2 domain interactions. Once activated in this manner, phosphory lated-STAT protein dimmers accumulate in the cell nucleus, bound to enhancer elements of target genes. They are the potential mediators of growth control and possibly oncogenic events. In particular, it became recognized that STAT3 were stimulated by classic growth-promoting signals, such as activated growth factor receptors, a considerable amount of experimental and clinical observations have now confirmed such a role for STAT3, and a remarkable degree of diversity has been uncovered for the molecular mechanisms at the basis of STAT3 action. Along with the study of it ,we found that the interruption of STAT3 signaling can inhibit many kinds of malignant tumors .Then, we wonder that if there is abnormal activation in endometrial carcinoma,and it's not definite that if the intervention of this signaling can effect the carcinogenesis,development and prognosis of endometrial carcinoma.On account of these reasons,We studied the expression of P-STAT3 protein in different tissues,their relationship with proliferation activity of tumor cells measured by Ki67 label index and their clinical significance in endometrial carcinoma. Besides,my study was further designed to explore the inhibition effect of signal inhibitor,in order to find evidence for reasonable compatibility of drugs.Materials and Methods1 .The tissues and cellsThe tissues: the 46 cases of endometrial carcinoma, 16 cases of normal paraffin -embeded tissues(include 8 proliferational and secretory endometrium,separately) came from the pathological department of the First Affiliated Hospital of ZhengZhou University. Among the total samples,the numbers of high,middle and low differentiation groups are 23,8,15, respectively. According to the operational and pathological stage: I:29; II:7; III～IV:10.There are 6 cases have the lymphatic metastasis.Cell culture:Ishikawa cells were grown in RPMI1640 containing 100U/ml penicillin, 100U/ml streptomycin, 10% fetus bull serum(FBS), under standard condition (humidified atomosphere, 5%CO2,37℃) passaged as usual. Cells were serial subcultivated with 0.25% pamcreatin when cells grow fully.2.The expression of P-STAT3 and Ki67 were detected by immunohistoche mistrial SP method.3.WST-1 assay was used to analyze the effect of AG490 (25,50,75,100μmol/L)and Cisplatin (0.375,,0.750,1.500,3.000μg/ml) single or combination (AG490 75μmol/L+cisplatin 3.0μg/ml) on the growth of Ishikawa cells. 4. Statistical analysis: All analyses were treated by the SPSS statistical package program 13.0.Aborbance value and contents of P-STAT3 were presented as x|-±s. The statistical methods included: (?)2 test,Spearman correlation analysis,one-way ANOVA. P<0.05 was considered statistically significant; P <0.01 was considered highly statistically significant.Results1. The expression of P-STAT3 and the relationship between P-STAT3 and the clinical and pathological factors: The positive rate of P-STAT3 in endometrial carcinoma (76.09%, 35/46) was significantly higher than that in normal endometrium, (proliferative endometrium 37.50%,3/8 ,(?)~2 = 4.867 ,p=0.027 < 0.05);secretory endometrium(25.00%, 2/8,(?)~2=8.245, p=0.004<0.01). The positive rate of P-STAT3 in early stages (I+ II stages,58.33%, 21/36) is lower than that in advanced stages(III+ IV stages,100%, 10/10) (p=0.019<0.05) .The positive rate of P-STAT3 in the group which has the lymphatic metastasis (83.33%,5/6) is higher than that in the lymphatic metastases,zero group (67.50%,26/40) ,but they have no statistical significance (p=0.647>0.05) .2.There was no Ki67 expression in secretory endometrium and the expression was mild in proliferative endometrium (0.22±0.05) %. The expression of Ki67 in endometrial carcinoma (28.56±9.21) % was higher than that in normal endometrium prominently (p=0.007<0.01) .3. The relationship between P-STAT3 and Ki67: The Ki67 label index are(26.48±11.56) %, (9.84±4.09) % in the 35 cases with P-STAT3 positive expression and the 11 cases with P-STAT3 negative expression, respectively. The difference between the two groups has statistical significance. The expression of P-STAT3 is positively correlated with the expression of Ki67 (r=0.693, P<0.05) .4.Effects of AG490 on proliferation of Ishikawa cells: The growth of cells was inhibited obviously suppressed by AG490 and Cisplatin when their concentations were 75μmol/L,3.0μg/ml,respectively. Comparing with the control group,the difference has a marked significance with the increase of drugs'concentration (P<0.01) . AG490 combined with Cisplatin inhibited Ishikawa cells significantly (P<0.01) ,the value of OD showing a dose-depengdent manner.Conclusion1.STAT3 was overactivated in endometrial carcinoma.STAT3 may play a important role at the carcinogenesis and progression of endometrial carcinoma. The overactived STAT3 in the cancer tissue may improve the malignant proliferation of tumor cells.2.AG490 combined with Cisplatin can significantly enhance the killing efficiency over the Ishikawa cells. It was convinced that the two drugs together would be more effective than Cisplatin or AG490.
|
PDF Full Text Request