title: Increased expression of heat shock protein 90 in keratinocytes and mast cells in patients with psoriasis.
abstract: BACKGROUND
  Psoriasis is a chronic inflammatory skin disease and various stress factors mediate inflammation. Heat shock protein (HSP) 90 plays an important role in cell survival; cytokine signaling, such as interleukin-17 receptor signaling; and immune responses.
  
  
  OBJECTIVE
  We sought to elucidate protein expression and distribution of HSP90 in psoriasis.
  
  
  METHODS
  HSP90 expression and its cellular source were analyzed on normal-appearing, nonlesional, lesional, and ustekinumab-treated psoriatic skin using immunohistochemistry and double immunofluorescence.
  
  
  RESULTS
  HSP90α, the inducible isoform of HSP90, was significantly up-regulated in epidermal keratinocytes and mast cells of lesional skin and down-regulated after ustekinumab therapy.
  
  
  CONCLUSIONS
  There was a limited sample size.
  
  
  CONCLUSIONS
  HSP90 from keratinocytes and mast cells is a key regulator of psoriatic inflammation and HSP90 inhibitors may represent a novel therapeutic approach to the disease.
authors: Department of Dermatology, Inselspital, Bern University Hospital, Bern, Switzerland; Department of Dermatology, Mie University Graduate School of Medicine, Mie, Japan.
authors: Masato
authors: M
authors: Kakeda
authors: Laboratoire Central d'Hématologie, Groupe Hospitalier Pitié-Salpêtrière (Paris), and LBPA, CNRS UMR 8113, Ecole Normale Supérieure de Cachan, Cachan, France.
authors: Michel
authors: M
authors: Arock
authors: Department of Dermatology, Inselspital, Bern University Hospital, Bern, Switzerland. Electronic address: christoph.schlapbach@insel.ch.
authors: Christoph
authors: C
authors: Schlapbach
authors: Department of Dermatology, Inselspital, Bern University Hospital, Bern, Switzerland.
authors: Nikhil
authors: N
authors: Yawalkar
mesh_terms: D000328:Adult; D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D016022:Case-Control Studies; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005786:Gene Expression Regulation; D018841:HSP90 Heat-Shock Proteins / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000166:cytology / Q000378:metabolism; D008875:Middle Aged; D058990:Molecular Targeted Therapy; D011565:Psoriasis / Q000188:drug therapy* / Q000235:genetics* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis; D012016:Reference Values; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D015854:Up-Regulation; D000069549:Ustekinumab
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D018841:HSP90 Heat-Shock Proteins; D012333:RNA, Messenger; D000069549:Ustekinumab
keywords: heat shock protein; heat shock protein 90; heat shock protein 90 inhibitor; keratinocytes; mast cells; psoriasis