title: Regulation of human endometrial stromal proliferation and differentiation by C/EBPβ involves cyclin E-cdk2 and STAT3.
abstract: During each menstrual cycle, the human uterus undergoes a unique transformation, known as decidualization, which involves endometrial stromal proliferation and differentiation. During this process, the stromal cells are transformed into decidual cells, which produce factors that prepare the uterus for potential embryo implantation. We previously identified the transcription factor CCAAT/enhancer-binding protein (C/EBP)β as a regulator of endometrial stromal proliferation and differentiation in mice. In this study, we addressed the role of C/EBPβ in human endometrial decidualization. Using small interfering RNA targeted to C/EBPβ mRNA, we demonstrated that C/EBPβ controls the proliferation of primary human endometrial stromal cells (HESCs) by regulating the expression of several key cell cycle-regulatory factors during the G(1)-S phase transition. Additionally, loss of C/EBPβ expression blocked the differentiation of HESCs in response to estrogen, progesterone, and cyclic AMP. Gene expression profiling of normal and C/EBPβ-deficient HESCs revealed that the receptor for the cytokine IL-11 and its downstream signal transducer signal transducer and activator of transcription 3 (STAT3) are targets of regulation by C/EBPβ. Chromatin immunoprecipitation analysis indicated that C/EBPβ controls the expression of STAT3 gene by directly interacting with a distinct regulatory sequence in its 5'-flanking region. Attenuation of STAT3 mRNA expression in HESCs resulted in markedly reduced differentiation of these cells, indicating an important role for STAT3 in decidualization. Gene expression profiling, using STAT3-deficient HESCs, showed an extensive overlap of pathways downstream of STAT3 and C/EBPβ during stromal cell differentiation. Collectively, these findings revealed a novel functional link between C/EBPβ and STAT3 that is a critical regulator of endometrial differentiation in women.
authors.affiliation: Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Robert N
authors.initials: RN
authors.lastname: Taylor
authors.forename: Indrani C
authors.initials: IC
authors.lastname: Bagchi
authors.forename: Milan K
authors.initials: MK
authors.lastname: Bagchi
mesh_terms: D022782:CCAAT-Enhancer-Binding Protein-beta / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D000242:Cyclic AMP / Q000378:metabolism; D019927:Cyclin E / Q000378:metabolism*; D051357:Cyclin-Dependent Kinase 2 / Q000378:metabolism*; D050687:E2F1 Transcription Factor / Q000096:biosynthesis / Q000378:metabolism; D010064:Embryo Implantation / Q000235:genetics / Q000502:physiology; D004717:Endometrium / Q000166:cytology* / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008597:Menstrual Cycle / Q000378:metabolism; D010766:Phosphorylation; D011374:Progesterone / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering; D053702:Receptors, Interleukin-11 / Q000235:genetics / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000096:biosynthesis / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics; D017154:Stromal Cells / Q000166:cytology* / Q000378:metabolism*; D014158:Transcription, Genetic; D014599:Uterus / Q000378:metabolism
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta; C545012:CEBPB protein, human; D019927:Cyclin E; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D004967:Estrogens; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D053702:Receptors, Interleukin-11; D016160:Retinoblastoma Protein; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D011374:Progesterone; D000242:Cyclic AMP; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2