title: Clinical significance of DJ-1 as a secretory molecule: retrospective study of DJ-1 expression at mRNA and protein levels in ductal carcinoma of the breast.
abstract: OBJECTIVE
  DJ-1 is a molecule secreted into serum by some breast cancer cells. However, little is known about the clinical significance of the DJ-1 expression.
  
  
  RESULTS
  Expression of DJ-1 protein was examined by immunohistochemistry, and expression of DJ-1 mRNA was detected using in-situ hybridization in 273 invasive ductal carcinomas (IDCs) and 41 ductal carcinomas in situ (DCISs) of the breast, and also in breast cancer cell lines. Breast cancer cells were examined for their secretion of DJ-1 using immunoblot analysis. By immunohistochemistry DJ-1 protein expression was lower than adjacent non-cancerous epithelium in 6 (14.6%) of the 41 DCISs and 146 (53%) of the 273 IDCs, even although all 314 carcinomas retained expression of DJ-1 mRNA, which was higher than that in adjacent non-cancerous epithelium in 220 cases (70%). Patients with IDC whose cancer cells showed low expression of DJ-1 protein had significantly shorter disease-free survival (P = 0.0152) and overall survival (P = 0.0196) than those whose cancer cells retained DJ-1 expression. MDA-MB-231 cells, which secreted DJ-1, showed low expression of DJ-1 protein.
  
  
  CONCLUSIONS
  Low expression of DJ-1 protein with high expression of its mRNA, which may reflect a secretory expression pattern, is predictive of poor outcome in patients with IDC.
authors.affiliation: Division of Molecular Diagnostics, Graduate School of Medical Sciences, Kitasato University, Sagamihara, Kanagawa, Japan. benio@med.kitasato-u.ac.jp
authors.forename: Benio
authors.initials: B
authors.lastname: Tsuchiya
authors.forename: Keiichi
authors.initials: K
authors.lastname: Iwaya
authors.forename: Norio
authors.initials: N
authors.lastname: Kohno
authors.forename: Takahiko
authors.initials: T
authors.lastname: Kawate
authors.forename: Tohru
authors.initials: T
authors.lastname: Akahoshi
authors.forename: Osamu
authors.initials: O
authors.lastname: Matsubara
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Mukai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001940:Breast / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000401:mortality / Q000556:secondary; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D007564:Japan / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen / Q000378:metabolism; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008408:Mastectomy; D008875:Middle Aged; D009367:Neoplasm Staging; D015513:Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D011379:Prognosis; D000071617:Protein Deglycase DJ-1; D012333:RNA, Messenger / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies; D015996:Survival Rate; D046888:Tissue Array Analysis; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D047908:Intracellular Signaling Peptides and Proteins; D019394:Ki-67 Antigen; D015513:Oncogene Proteins; D000071617:Protein Deglycase DJ-1; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human; C105131:PARK7 protein, human