title: Identification of a myometrial molecular profile for dystocic labor.
abstract: BACKGROUND
  The most common indication for cesarean section (CS) in nulliparous women is dystocia secondary to ineffective myometrial contractility. The aim of this study was to identify a molecular profile in myometrium associated with dystocic labor.
  
  
  METHODS
  Myometrial biopsies were obtained from the upper incisional margins of nulliparous women undergoing lower segment CS for dystocia (n = 4) and control women undergoing CS in the second stage who had demonstrated efficient uterine action during the first stage of labor (n = 4). All patients were in spontaneous (non-induced) labor and had received intrapartum oxytocin to accelerate labor. RNA was extracted from biopsies and hybridized to Affymetrix HuGene U133A Plus 2 microarrays. Internal validation was performed using quantitative SYBR Green Real-Time PCR.
  
  
  RESULTS
  Seventy genes were differentially expressed between the two groups. 58 genes were down-regulated in the dystocia group. Gene ontology analysis revealed 12 of the 58 down-regulated genes were involved in the immune response. These included (ERAP2, (8.67 fold change (FC)) HLA-DQB1 (7.88 FC) CD28 (2.60 FC), LILRA3 (2.87 FC) and TGFBR3 (2.1 FC)) Hierarchical clustering demonstrated a difference in global gene expression patterns between the samples from dystocic and non-dystocic labours. RT-PCR validation was performed on 4 genes ERAP2, CD28, LILRA3 and TGFBR3
  
  
  CONCLUSIONS
  These findings suggest an underlying molecular basis for dystocia in nulliparous women in spontaneous labor. Differentially expressed genes suggest an important role for the immune response in dystocic labor and may provide important indicators for new diagnostic assays and potential intrapartum therapeutic targets.
authors: National Maternity Hospital, Dublin , Ireland.
authors: Donal J
authors: DJ
authors: Brennan
authors: Sharon F
authors: SF
authors: McGee
authors: Elton
authors: E
authors: Rexhepaj
authors: Darran P
authors: DP
authors: O'Connor
authors: Michael
authors: M
authors: Robson
authors: Colm
authors: C
authors: O'Herlihy
mesh_terms: D000328:Adult; D000626:Aminopeptidases / Q000235:genetics; D016022:Case-Control Studies; D002585:Cesarean Section; D015536:Down-Regulation; D004420:Dystocia / Q000175:diagnosis* / Q000235:genetics; D005260:Female; D006801:Humans; D009215:Myometrium / Q000378:metabolism*; D010298:Parity; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012313:RNA / Q000032:analysis; D014590:Uterine Contraction
chemical_list: D012313:RNA; D000626:Aminopeptidases; C503944:ERAP2 protein, human