title: Id-1 and Id-2 proteins as molecular markers for human prostate cancer progression.
abstract: OBJECTIVE
  Id proteins are dominant-negative regulators of basic helix-loop-helix transcription factors that control malignant cell behavior in many different tissues. This study aimed to identify the potential role of Id-1 and Id-2 proteins as molecular makers for prostate cancer progression.
  
  
  METHODS
  Using the technique of immunohistochemistry, we determined Id-1 and Id-2 expression in a panel of 67 human prostate biopsies. We also manipulated Id-1 and Id-2 expression in LNCaP and PC3 prostate cancer cell lines and determined the effects on invasion in vitro, matrix metalloproteinase secretion, and proliferation.
  
  
  RESULTS
  Both Id-1 and Id-2 proteins were up-regulated during human prostate cancer progression in vivo and were overexpressed in highly aggressive prostate cancer cells. In vitro, constitutive expression of Id-1, and to a lesser extent Id-2, converted nonaggressive LNCaP prostate cancer cells into more proliferative and invasive cells and increased their secretion of matrix metalloproteinases. Conversely, the down-regulation of Id-2 expression in highly metastatic PC3 cells reduced their growth potential and invasiveness.
  
  
  CONCLUSIONS
  We propose that both Id-1 and Id-2 proteins control prostate cancer cell phenotypes and could serve as molecular markers of aggressive human prostate cancer.
authors.affiliation: California Pacific Medical Center, Cancer Research Institute, San Francisco, California 94115, USA.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Coppe
authors.forename: Yoko
authors.initials: Y
authors.lastname: Itahana
authors.forename: Dan H
authors.initials: DH
authors.lastname: Moore
authors.forename: James L
authors.initials: JL
authors.lastname: Bennington
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Desprez
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000235:genetics; D018450:Disease Progression; D018257:Helix-Loop-Helix Motifs; D006801:Humans; D051798:Inhibitor of Differentiation Protein 1; D051797:Inhibitor of Differentiation Protein 2; D008297:Male; D009361:Neoplasm Invasiveness; D011471:Prostatic Neoplasms / Q000235:genetics / Q000473:pathology*; D012097:Repressor Proteins / Q000032:analysis* / Q000235:genetics; D014157:Transcription Factors / Q000032:analysis* / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; C497453:ID1 protein, human; C497450:ID2 protein, human; D051798:Inhibitor of Differentiation Protein 1; D051797:Inhibitor of Differentiation Protein 2; D012097:Repressor Proteins; D014157:Transcription Factors