The Study Of Stradiol Produced VEGF、bFGF、IL-8in Endometrial Cancer By Activated NF-κB Via Akt

Background Endometrial cancer is the most common gynecologic malignancy. In recent years, with the extension of average life expectancy of women and, the addition in the proportion of obesity and other factors, the incidence of endometrial cancer in all ages of women shoeed an upward trend. That the occurrence of endometrial cancer may be related to over-exposure to estradiol that is not inhibited by progesterone.PI3k/Akt is a classical important signaling pathway in intracellular signal transduction pathways. AKT (Serine/threonine protein kinase) is the core of the PI3k/Akt signal pathways, is closely related to cell survival and apoptosis, differentiation and metabolism.NF-k B (nuclear factor-kappa B) is a more important key nuclear transcription factor, involved avriety of gene regulation in apoptosis, and tumorigenesis and metastasis.Objective The main aims are to study whether estradiol was induced the expression of VEGF、 bFGF、IL-8in the endometrial cancer cells by Activated NF-k B via Akt, and its associated intracellular signal channel activation and conduction mechanism. In this study, Endometrial cancer cell lines Ishikawa (ER-positive) and HEC-1A(ER-weak positive) were treated by estradiol,then detected the expression of mRNA and protein of VEGF, bFGF and IL-8to described the relationship between endometrial carcinoma and estradiol. To observe estrogen-induced moleculars changes in NF-k B signaling pathway in human endometrial carcinoma Ishikawa cells transplanted into BALB/c nude miceMethod1. Real-time quantitative PCR was detected the expression of mRNA of VEGF, bFGF and IL-8in HEC-1A、Ishikawa cells after stimulation with l×10-6mol/L estradiol for30min, and with being pretreated with l×10-bmol/L ER inhibitor(ER inhibitor group) or25×10-6mol/L AKT inhibitor (AKT inhibitor group) or100u mol/L NF-k B inhibitor(NF-k B inhibitor group) for1h, following stimulation with l×10-6mol/L estradiol for30min.2、Western Blot was detected the expression of VEGF、bFGF protein in human endometrial cancer cell lines HEC1A、Ishikawa after stimulation with1×10-6mol/L estradiol for30min; and with being pretreated withl X10-6mol/L ER inhibitor (ER inhibitor group) or25×10-6mol/L AKT inhibitor (AKT inhibitor group) or100μ mol/L NF-kB inhibitor(NF-kB inhibitor group) for60min, following stimulation with1×10-6mol/L estradiol for30min.3. The subcutaneously transplanted tumor model of human endometrial carcinoma Ishikawa cells in nude mice was established. After continuously intraperitoneal injection with different doses of estrogen for21d, the mice were sacrificed. Then the tumor weight and volume were measured, and the tumor inhibition rate was calculated. Tumor-bearing mice randomly divided into5groups. Expression of AKT、NF-κB、 VEGF、bFGF changes of Ishikawa cells were detected by HE stain and immunohistochemical method.Result1、Real-time PCR showed the expression of VEGF, bFGF, IL-8mRNA in estradiol group were significantly increased than that in control group (P＜0.05); the expression of VEGF, bFGF, IL-8mRNA in AKT inhibitor group and ER inhibitor group and NF-κB inhibitor group were significantly decreased than that in estradiol group (P＜0.05).2、Western Blot showed that the expression of VEGF、bFGF protein in HEC-1A、Ishikawa cells after stimulation with1×10-6mol/L estradiol for30min was markedly higher than that in the control group (P＜O.05); the expression of VEGF、bFGF protein expression in ER inhibitor group and AKT inhibitor group or NF-κ B inhibitor group were significantly decreased than that in estradiol group(P＜0.05).3.The relative tumor volumes (V/V0) were significantly smaller in the ER, AKT and NF-κ B treated groups (5.32±0.28,5.55±0.15and1.57±0.23, respectively) than that in the E2group (11.37±0.37; P<0.01). Immunohistochemistry analysis had showed that the expression of VEGF、 bFGF in all treatment groups were lower than that in E2group, but the expression of E2group was higher than that in the control group. Differences between the treatment groups and the control group was statistically significant (P＜.05), so as the difference among treatment groups(P＜0.05).Conclusion Estradiol can regulate the activity of NF-κB, may be through the AKT signaling pathway. Estrogen induced the production of VEGF, bFGF and IL-8via a mechanism involving activation AKT signal transmission pathway.