title: MicroRNA and Embryo Implantation.
abstract: OBJECTIVE
  In mammals, implantation involves interactions between an activated blastocyst and a receptive endometrium. There are controversies on the role of microRNAs in preimplantation embryo development. The actions of endometrial microRNAs on implantation are beginning to be understood.
  
  
  METHODS
  Review of literature on microRNAs in preimplantation embryos and endometrium.
  
  
  RESULTS
  Emerging evidence suggests a role of microRNAs in blastocyst activation and implantation. Differential expression of microRNAs is found between receptive and non-receptive endometria. Members of the let-7, miR-200, miR-30 families, and the miR-17-92 clusters are more commonly found to be associated with endometrial receptivity. Experimental studies show that the targets of the differentially expressed microRNAs affect endometrial receptivity, decidualization, and embryo implantation. Free and exosome/microvesicle containing microRNAs have been detected in human and ovine uterine luminal fluid (ULF). They may serve as mediators of embryo-endometrium dialog. Some observations suggest that the microRNAs in ULF may be used as biomarkers in infertility treatment.
  
  
  CONCLUSIONS
  MicroRNAs in endometrium and blastocysts are involved in the implantation process.
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.|Shenzhen Institute of Research and Innovation, University of Hong Kong, Shenzhen, China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
authors.forename: Ziru
authors.initials: Z
authors.lastname: Niu
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
authors.forename: Ronald T K
authors.initials: RT
authors.lastname: Pang
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.|ShenZhen Key Laboratory of Fertility Regulation, Shenzhen Hospital, The University of Hong Kong, Shenzhen, China.
authors.forename: Philip C N
authors.initials: PC
authors.lastname: Chiu
authors.affiliation: Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.|Shenzhen Institute of Research and Innovation, University of Hong Kong, Shenzhen, China.|ShenZhen Key Laboratory of Fertility Regulation, Shenzhen Hospital, The University of Hong Kong, Shenzhen, China.
authors.forename: William Shu-Biu
authors.initials: WS
authors.lastname: Yeung
mesh_terms: D000818:Animals; D003656:Decidua / Q000276:immunology*; D010064:Embryo Implantation / Q000276:immunology*; D004622:Embryo, Mammalian / Q000276:immunology*; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000276:immunology*; D006801:Humans; D035683:MicroRNAs / Q000276:immunology*; D011247:Pregnancy / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology
chemical_list: D035683:MicroRNAs
keywords: Endometrium; exosome; implantation; microRNA; microvesicle; preimplantation embryo