title: Gene expression and tyrosine kinase activity of insulin receptor in uterine leiomyoma and matched myometrium.
abstract: OBJECTIVE
  Our objective was to determine the insulin receptor (IR) mRNA levels and IR tyrosine kinase activity in normal myometrium and leiomyoma.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Academic research center.
  
  
  METHODS
  Five women with leiomyoma submitted to hysterectomy.
  
  
  METHODS
  Plasma membrane fraction of human myometrium and leiomyoma were prepared and samples were incubated with and without insulin. mRNA was isolated and RT-PCR with specific primers was performed.
  
  
  METHODS
  Western blots of plasma membranes incubated with and without insulin were performed. Chemoluminescent methods followed by densitometry were used to assess IR autophosphorylation. RT-PCR with specific primers for IR gene sequences was used to determine IR mRNA levels.
  
  
  RESULTS
  IR mRNA levels in myometrium (0.634+/-0.038) and in leiomyoma (0.649+/-0.047; p=0.813) were not different. The degree of insulin-stimulated IR autophosphorylation (relative optical density of the 95 kDa band) was also not different between myometrium (1.496+/-0.310) and leiomyoma (1.593+/-0.129; p=0.650).
  
  
  CONCLUSIONS
  There was no difference in IR receptor expression and IR autophosphorylation between normal myometrium and leiomyoma. Other steps of insulin signaling chain may participate in the altered proliferation of leiomyomas.
authors.affiliation: Departamento de Fisiologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Guilherme Kirjner
authors.initials: GK
authors.lastname: Toscani
authors.forename: Eunice Martin
authors.initials: EM
authors.lastname: Chaves
authors.forename: Fabíola Lara
authors.initials: FL
authors.lastname: Cervi
authors.forename: Marcelo Belmonte
authors.initials: MB
authors.lastname: Tavares
authors.forename: Ilma Simoni Brum da
authors.initials: IS
authors.lastname: Silva
authors.forename: Helena
authors.initials: H
authors.lastname: von Eye Corleta
authors.forename: Edison
authors.initials: E
authors.lastname: Capp
mesh_terms: D015153:Blotting, Western; D016022:Case-Control Studies; D017931:DNA Primers; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007889:Leiomyoma / Q000378:metabolism*; D009215:Myometrium / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014594:Uterine Neoplasms / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin