The Expression Of Insulin Like Growth Factor Binding Protein-related Protein1(IGFBP-rP1) In Endometrial Adenocarcinoma And Its Clinical Significance

Background and ObjectiveEndometrial carcinoma is one of the most common malignant tumors in the female reproductive system，and the incidence is rising worldwide. But there are no significant improvement in the cure rate. Endometrial cancer is a type I endometrial cancer, It is well known that a high risk population of endometrial cancer is the one who is suffering Obesity, hypertension, hyper-lipidemia, diabetes, which are the characteristics of metabolic syndrome.The basis of metabolic syndrome is insulin resistance. Therefore, the relationship between insulin resistance and endometrial cancer become a hot topic in the field in recent years. Insulin-like growth factor system is a focus of insulin resistance studying. IGFBPs is an important part of the IGF system.There have found that15members of the family, According to the combining capacity with IGF, it can be divided into two categories: IGFBPl-6with a higher binding capacity with IGF,and IGFBP7-15with lower binding ability with IGF, The latter is also known as insulin-like growth factor binding protein-associated protein(IGFBP-rP), IGFBP7is IGFBP-rP1.Due to its strong binding ability with insulin ability it has been widely concerned.After combining with IGFBP-rP1，insulin lose or reduce the physiological effect, resulting in a decline in insulin sensitivity and insulin resistance.To participate in the development some malignant tumors such as colon cancer, breast cancer and prostate cancer. But there are fewer research in endometrial cancer. Our study is to explore the expression of insulin like growth factor-binding protein7in endometrial adenocarcinoma and its relationship between the clinicopathological parameters of endometrial adenocarcinoma.MaterialSelecting archived paraffin-embedded endometrial resection specimens of93cases,in First Affiliated Hospital of Zhengzhou University,Department of Pathology from January2011to December2012. including61cases of endometrial adenocarcinoma,22cases of atypical endometrial hyperplasia10cases of simple endometrial hyperplasia. They did not receive chemotherapy and hormone therapy before operative. Patients were from36to72years old, median age was53. The average height of patients with endometrial adenocarcinoma was1.59m, an average weight of64.92kg, mean BMI (body mass index, BMI)25.83kg/m2, BMI≥25kg/m250cases,<25kg/m211cases. FIGO (2000) surgical stage: stageⅠ50cases, stageⅡ4cases, stage Ⅲ7cases; pathological grading: G1phase29cases, G2phase29cases, G3phase,3cases; myometrial invasion depth:≤1/249cases,>1/212cases; surgery confirmed6cases with lymph node metastasis,55patients without lymph node metastasis;49cases with hypertension,22cases with diabetes mellitus.MethodsImmunohistochemistry (SP) were used to detected the IGFBP-rP1expressions in endometrial cancer.Analyzing the relationship between the positive expression rates of IGFBP-rP1and clinicopathological parameters of endometrial adenocarcinoma. The expressions of IGFBP-rP1mRNA were detected by the real-time fluorescence quantitative polymerase chain reaction (RT-PCR). Results1.Immunohistochemical SP method showed that the positive immunostaining rates of IGFBP-rP1in endometrial adenocarcinoma （51/60,85.0%）was significantly higher(χ2=16.764P＜0.05) than the atypical endometrial hyperplasia（14/22,63.6%） and Simple endometrial hyperplasia（2/10,20%）. The expression of IGFBP-rP1correlated with the pathological grade（χ2=3.399P＜0.05）、fat（46/50，92.0%χ2=18.882P＜0.01）、with hypertension （44/49，89.8%,χ2=10.328P＜0.01）and diabetes mellitus（21/22，95.5%χ2=4.235P＜0.05）.The expression of IGFBP-rP1had no correlation with pathological stage(χ2=4.783P>0.05)、lymph node metastasis(χ2=1.464P>0.05) and depth of invasion(χ2=0.019P>0.05).2.RT-PCR showed that the expression rates of IGFBP-rP1mRNA in endometrial adenocarcinoma was significantly higher（t=6.12,P＜0.01t=4.45,P＜0.01)than in atypical endometrial hyperplasia, Simple endometrial hyperplasia and normal endometrium.Conclusion1.IGFBP-rP1is a cancer-promoting factor in the pathogenesis of endometrial adenocarcinoma.IGFBP-rP1can promote the proliferation and dedifferentiation of endometrial cancer.2.IGFBP-rP1is associated with insulin resistance.IGFBP-rP1is likely to promote the occurrence of endometrial adenocarcinoma by promoting insulin resistance.