Mechanism Of Progesterone Regulates Endometrial Receptivive Marker HOXA10

Objective:To analyze the HOXA10 expression in endometrium under high progesterone circumstance on h CG day of IVF-ET cycles,and explore the mechanism of progesterone regulating HOXA10.Methods:1.Infertile women with fresh ET（embryo transfer,ET）cancelled in IVF/ICSI cycles were enrolled in this study.30 patients were assigned to high progesterone group（P≥2.10 ng/m L）groups according to their serum progesterone levels on day of HCG administration,and 30 females with natural ovulation as control group Endometium was obtained via Pipelle 7-8 days after egg collection or ovulation monitored by B-ultrasound.The expression of endometrial HOXA10 and mi R135a was detected and analyzed by immunohistochemistry,Westrn Blot and q RT-PCR.2.In vitro experiments were carried out with different concentrations of0,10^-8,10^-7,10^-6,10^-5Mprogesterone co-cultured Ishikawa cells24h,HOXA10,mi R-135a expression were detected by Western Blot and RT-PCR;The targeted regulation of HOXA10 by mi R-135a were verified by the luciferase reporter system;after overexpressed and inhibited the expression of mi R-135a 48h,the expression of HOXA10 were detected.Results:1.Compared with the control group,the endometrial HOXA10 expression was decreased（p<0.05）,and mi R-135a expression was increased（p<0.01）in the high progesterone group.2.HOXA10 is mainly expressed in endometrial glandular epithelial cells,and hardly expressed in endometrial stromal cells.3.The expression of HOXA10 was increased（p<0.05）and the expression of mi R-135a decreased in Ishikawa cells（p<0.05）after co-culture with progesterone from 10-8 to 10-6M compared with control;When the progesterone concentration increased to 10-5M,HOXA10 expression was significantly decreased（p<0.01）,and the expression of mi R-135a was significantly increased in cells（p<0.05）compared to control;Luciferase Assays and Reporters result showed:compared with the control group,when mi R-135a was overexpressed（transfected mi R-135a mimics 20n M）,the transfection of HOXA10 3’UTR wild type（WT）vector plasmid group fluorescence activity was significantly decreased（p<0.01）;and the expression of HOXA10 was decreased（p<0.01）;after mi R-135a was inhibited,the expression of HOXA10 was increased（p<0.01）.Conclusion:In IVF-ET cycles,the expression of endometrial HOXA10 was decreased under high progesterone levels on HCG day,wich impaire the endometrial receptivity The molecular mechanism is as follows:high concentration of progesterone up-regulates the expression of mi R-135a,resulting in the decrease of HOXA10.