title: Identification of a novel autoantibody reactive with 155 and 140 kDa nuclear proteins in patients with dermatomyositis: an association with malignancy.
abstract: OBJECTIVE
  Myositis-specific autoantibodies (MSAs) are a useful tool in diagnosis, defining clinical subsets and predicting prognosis of dermatomyositis (DM) and polymyositis (PM). In this study, we identified a novel MSA reactive with 155 and 140 kDa nuclear proteins [anti-155/140 antibody (Ab)] and determined the clinical feature of DM patients positive for this autoantibody (autoAb).
  
  
  METHODS
  Sera from 52 Japanese patients with DM, 9 with PM, 48 with systemic lupus erythematosus (SLE), 126 with systemic sclerosis and 18 with idiopathic interstitial pneumonia were examined by immunoprecipitation assays. Positive sera were further characterized by immunodepletion and immunofluorescence staining.
  
  
  RESULTS
  Seven of the 52 (13%) Japanese patients with DM immunoprecipitated 155 and 140 kDa proteins from 35S-labelled K562 leukaemia cell extract. No patients with SLE, systemic sclerosis or idiopathic interstitial pneumonia as well as healthy controls were positive for this autoAb. Patients with anti-155/140 Ab developed heliotrope rash, Gottron's papules or sign and flagellate erythema significantly more frequently than those negative. Notably, internal malignancy was found at significantly higher frequency in those positive than those negative (71 vs 11%; P < 0.005). In contrast, none of these patients positive for this autoAb had interstitial lung disease.
  
  
  CONCLUSIONS
  This novel MSA is associated with cancer-associated DM and may serve as a diagnostic serological marker for this specific subset.
authors.affiliation: Department of Dermatology, Kanazawa University Graduate School of Medical Science, 13-1 Takaramachi, Kanazawa, Ishikawa 920-8641, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kaji
authors.forename: M
authors.initials: M
authors.lastname: Fujimoto
authors.forename: M
authors.initials: M
authors.lastname: Hasegawa
authors.forename: M
authors.initials: M
authors.lastname: Kondo
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Komura
authors.forename: T
authors.initials: T
authors.lastname: Matsushita
authors.forename: H
authors.initials: H
authors.lastname: Orito
authors.forename: Y
authors.initials: Y
authors.lastname: Hamaguchi
authors.forename: K
authors.initials: K
authors.lastname: Yanaba
authors.forename: M
authors.initials: M
authors.lastname: Itoh
authors.forename: Y
authors.initials: Y
authors.lastname: Asano
authors.forename: M
authors.initials: M
authors.lastname: Seishima
authors.forename: F
authors.initials: F
authors.lastname: Ogawa
authors.forename: S
authors.initials: S
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Takehara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000974:Antibodies, Antinuclear / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003882:Dermatomyositis / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005260:Female; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods; D020014:K562 Cells; D017563:Lung Diseases, Interstitial / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications* / Q000276:immunology; D009687:Nuclear Proteins / Q000276:immunology*; D010257:Paraneoplastic Syndromes / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D012595:Scleroderma, Systemic / Q000276:immunology
chemical_list: D000974:Antibodies, Antinuclear; D015415:Biomarkers; D009687:Nuclear Proteins