title: Anti-NXP2 autoantibodies in adult patients with idiopathic inflammatory myopathies: possible association with malignancy.
abstract: OBJECTIVE
  Myositis-specific autoantibodies (MSAs) are useful tools for identifying clinically homogeneous subsets and predicting prognosis of patients with idiopathic inflammatory myopathies (IIM) including polymyositis (PM) and dermatomyositis (DM). Recent studies have shown that anti-NXP2 antibody (Ab) is a major MSA in juvenile dermatomyositis (JDM). In this study the frequencies and clinical associations of anti-NXP2 Ab were evaluated in adult patients with IIM.
  
  
  METHODS
  Clinical data and serum samples were collected from 507 adult Japanese patients with IIM (445 with DM and 62 with PM). Eleven patients with JDM, 108 with systemic lupus erythematosus, 433 with systemic sclerosis and 124 with idiopathic pulmonary fibrosis were assessed as disease controls. Serum was examined for anti-NXP2 Ab by immunoprecipitation and western blotting using polyclonal anti-NXP2 Ab.
  
  
  RESULTS
  Seven patients (1.6%) with adult DM and one (1.6%) with adult PM were positive for anti-NXP2 Ab. Except for two patients with JDM, none of the disease controls were positive for this autoantibody. Among eight adult patients with IIM, three had internal malignancies within 3 years of diagnosis of IIM. Another patient with DM also had a metastatic cancer at the diagnosis. All of the carcinomas were at an advanced stage (stage IIIb-IV).
  
  
  CONCLUSIONS
  While less common than in juvenile IIM, anti-NXP2 Ab was found in adult IIM. Anti-NXP2 Ab may be associated with adult IIM with malignancy.
authors.affiliation: School of Medicine, Kanazawa University, Kanazawa, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ichimura
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsushita
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Hamaguchi
authors.forename: Kenzo
authors.initials: K
authors.lastname: Kaji
authors.forename: Minoru
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Tanino
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Inokoshi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kawai
authors.forename: Takuro
authors.initials: T
authors.lastname: Kanekura
authors.forename: Maria
authors.initials: M
authors.lastname: Habuchi
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Igarashi
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Sogame
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Koga
authors.forename: Ayako
authors.initials: A
authors.lastname: Nishino
authors.forename: Naoko
authors.initials: N
authors.lastname: Ishiguro
authors.forename: Naoki
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Rui
authors.initials: R
authors.lastname: Aoki
authors.forename: Noriko
authors.initials: N
authors.lastname: Ando
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Abe
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanda
authors.forename: Masataka
authors.initials: M
authors.lastname: Kuwana
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Takehara
authors.forename: Manabu
authors.initials: M
authors.lastname: Fujimoto
mesh_terms: D000251:Adenosine Triphosphatases / Q000032:analysis / Q000276:immunology*; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000032:analysis / Q000276:immunology*; D003882:Dermatomyositis / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009369:Neoplasms / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D017285:Polymyositis / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D004268:DNA-Binding Proteins; D000251:Adenosine Triphosphatases; C551732:MORC3 protein, human