title: Expression of Nodal, Cripto, SMAD3, phosphorylated SMAD3, and SMAD4 in the proliferative endometrium of women with endometriosis.
abstract: BACKGROUND
  Nodal is a growth factor of the transforming growth factor β superfamily that is expressed in high turnover tissues, such as the human endometrium, and in several malignancies. The effects of Nodal are modulated by the coreceptor Cripto and mediated by SMAD proteins. This study evaluated the gene and protein expression of Nodal, Cripto, total and phosphorylated (p) SMAD3, and SMAD4 in the proliferative endometrium of women with and without endometriosis.
  
  
  METHODS
  Total RNA was isolated and complementary DNA synthesized from eutopic endometrium of women with (n = 15) and without (n = 12) endometriosis, followed by quantitative real-time polymerase chain reaction (PCR) to evaluate the gene expression of Nodal, Cripto, SMAD3, and SMAD4. Western blot was used to evaluate the protein levels of Nodal and Cripto, and immunohistochemistry was performed to localize SMAD3, pSMAD3, and SMAD4.
  
  
  RESULTS
  Although Nodal expression was unchanged in women with endometriosis, real-time PCR indicated lower gene expression of Cripto (fold change 0.27, P < .05) in the endometriosis group. This difference, however, was not maintained at protein expression level as assessed by Western blot. The immunostaining of total SMAD3 was reduced in the endometriosis group (P < .01), but the localization of pSMAD3 and the nuclear staining of SMAD4 were unchanged.
  
  
  CONCLUSIONS
  These findings suggest that the Nodal signaling pathway has subtle changes in the endometrium of women with endometriosis, but this imbalance may not cause functional damage as it seems not to affect the nuclear expression of SMAD4.
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Cynthia Dela
authors.initials: CD
authors.lastname: Cruz
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Helen L
authors.initials: HL
authors.lastname: Del Puerto
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Ana Luiza L
authors.initials: AL
authors.lastname: Rocha
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Inês K
authors.initials: IK
authors.lastname: Cavallo
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Alessandra D
authors.initials: AD
authors.lastname: Clarizia
authors.affiliation: Department of Molecular and Developmental Medicine, Section of Obstetrics and Gynecology, University of Siena, Siena, Italy.
authors.forename: Felice
authors.initials: F
authors.lastname: Petraglia
authors.affiliation: Division of Human Reproduction, Department of Obstetrics and Gynecology, Federal University of Minas Gerais, Belo Horizonte, Brazil reis@medicina.ufmg.br.
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Reis
mesh_terms: D000328:Adult; D015153:Blotting, Western; D016022:Case-Control Studies; D049109:Cell Proliferation; D004715:Endometriosis / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism*; D004717:Endometrium / Q000737:chemistry* / Q000473:pathology; D005260:Female; D058851:GPI-Linked Proteins / Q000032:analysis* / Q000235:genetics; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis* / Q000235:genetics; D009363:Neoplasm Proteins / Q000032:analysis* / Q000235:genetics; D055457:Nodal Protein / Q000032:analysis* / Q000235:genetics; D010766:Phosphorylation; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D051900:Smad3 Protein / Q000032:analysis* / Q000235:genetics; D051901:Smad4 Protein / Q000032:analysis* / Q000235:genetics; D055815:Young Adult
chemical_list: D058851:GPI-Linked Proteins; D036341:Intercellular Signaling Peptides and Proteins; C526007:NODAL protein, human; D009363:Neoplasm Proteins; D055457:Nodal Protein; D012333:RNA, Messenger; C497790:SMAD3 protein, human; C497796:SMAD4 protein, human; D051900:Smad3 Protein; D051901:Smad4 Protein; C070636:TDGF1 protein, human
keywords: Cripto; Nodal; SMADs; endometriosis; endometrium