title: Down-regulated expression of prostasin in high-grade or hormone-refractory human prostate cancers.
abstract: BACKGROUND
  We previously conducted a search for genes which are differentially expressed in hormone-refractory prostate cancers using cDNA-representational difference analysis (RDA). The prostasin gene was isolated as one showing down-regulation in hormone-refractory cancers. In the present study, linkage to the stage in prostate neoplasia was examined.
  
  
  METHODS
  Prostasin expressions in 54 prostate cancer cases were examined by mRNA in situ hybridization and immunohistochemistry as well as by northern blot analysis.
  
  
  RESULTS
  Expression levels of prostasin in hormone-refractory cancers were approximately one-sixth of those in organ-confined cancers by northern blotting. Glandular components in benign prostatic hyperplasia and high-grade prostatic intraepithelial neoplasias tended to exhibit mild to moderate and relatively strong intensities, respectively. Expression levels of both prostasin mRNA and protein were inversely correlated with histological differentiation but not associated with clinical stage of human prostate cancer. Almost all cases of metastatic and hormone-refractory cancers demonstrated down-regulation of prostasin expression.
  
  
  CONCLUSIONS
  These results suggest that prostasin cannot be regarded as a prognostic indicator for human prostate cancer although it may be a useful marker for tumor differentiation.
authors.affiliation: Department of Experimental Pathology and Tumor Biology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Japan. sattak@med.nagoya-cu.ac.jp
authors.forename: Satoru
authors.initials: S
authors.lastname: Takahashi
authors.forename: Shugo
authors.initials: S
authors.lastname: Suzuki
authors.forename: Shingo
authors.initials: S
authors.lastname: Inaguma
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ikeda
authors.forename: Young-Man
authors.initials: YM
authors.lastname: Cho
authors.forename: Norio
authors.initials: N
authors.lastname: Hayashi
authors.forename: Takahiro
authors.initials: T
authors.lastname: Inoue
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Sugimura
authors.forename: Naoki
authors.initials: N
authors.lastname: Nishiyama
authors.forename: Tamio
authors.initials: T
authors.lastname: Fujita
authors.forename: Julie
authors.initials: J
authors.lastname: Chao
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Ushijima
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shirai
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000503:physiopathology*; D000918:Antibody Specificity; D014408:Biomarkers, Tumor / Q000235:genetics*; D018076:DNA, Complementary / Q000032:analysis; D015536:Down-Regulation; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000503:physiopathology*; D012333:RNA, Messenger / Q000032:analysis; D012697:Serine Endopeptidases / Q000032:analysis / Q000235:genetics* / Q000276:immunology; D000099271:Prostasin
chemical_list: D014408:Biomarkers, Tumor; D018076:DNA, Complementary; D012333:RNA, Messenger; D012697:Serine Endopeptidases; D000099271:Prostasin