title: Differential hRad17 expression by histologic subtype of ovarian cancer.
abstract: BACKGROUND
  In the search for unique ovarian cancer biomarkers, ovarian specific cDNA microarray analysis identified hRad17, a cell cycle checkpoint protein, as over-expressed in ovarian cancer. The aim of this study was to validate this expression.
  
  
  METHODS
  Immunohistochemistry was performed on 72 serous, 19 endometrioid, 10 clear cell, and 6 mucinous ovarian cancers, 9 benign ovarian tumors, and 6 normal ovarian tissue sections using an anti-hRad17 antibody. Western blot analysis and quantitative PCR were performed using cell lysates and total RNA prepared from 17 ovarian cancer cell lines and 6 normal ovarian epithelial cell cultures (HOSE).
  
  
  RESULTS
  Antibody staining confirmed upregulation of hRad17 in 49.5% of ovarian cancer cases. Immunohistochemistry demonstrated that only 42% of serous and 47% of endometrioid subtypes showed overexpression compared to 80% of clear cell and 100% of mucinous cancers. Western blot confirmed overexpression of hRad17 in cancer cell lines compared to HOSE. Quantitative PCR demonstrated an upregulation of hRad17 RNA by 1.5-7 fold. hRad17 RNA expression differed by subtype.
  
  
  CONCLUSIONS
  hRad17 is over-expressed in ovarian cancer. This over-expression varies by subtype suggesting a role in the pathogenesis of these types. Functional studies are needed to determine the potential role of this protein in ovarian cancer.
authors: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, SC, USA. youngjl@musc.edu.
authors: Jennifer L
authors: JL
authors: Young
authors: E Colin
authors: EC
authors: Koon
authors: Joseph
authors: J
authors: Kwong
authors: William R
authors: WR
authors: Welch
authors: Michael G
authors: MG
authors: Muto
authors: Ross S
authors: RS
authors: Berkowitz
authors: Samuel C
authors: SC
authors: Mok