title: High insulin-like growth factor-2 (IGF-2) gene expression is an independent predictor of poor survival for patients with advanced stage serous epithelial ovarian cancer.
abstract: OBJECTIVE
  Epithelial ovarian cancer is the deadliest gynecologic malignancy, yet its molecular etiology remains poorly understood. Evidence is accumulating to support a role for the insulin-like growth factor family in human carcinogenesis, and recently using microarray expression analysis, we demonstrated over-expression of the insulin-like growth factor-2 (IGF-2) gene in advanced stage epithelial ovarian cancers. The purpose of the current study is to further elucidate the role of the IGF-2 gene in ovarian cancer development and progression.
  
  
  METHODS
  Relative expression of IGF-2 was measured in 109 epithelial ovarian cancers and eight normal ovarian surface epithelial (NOSE) samples, using quantitative real-time polymerase chain reaction. Associations with clinicopathological parameters were examined.
  
  
  RESULTS
  Expression of the IGF-2 gene was more than 300-fold higher in ovarian cancers compared with normal ovarian surface epithelium samples (P <0.001). High IGF-2 expression was associated with advanced stage disease at diagnosis (P <0.001), high-grade cancers (P <0.05) and sub-optimal surgical cytoreduction (P = 0.08). In multivariate analysis, relative IGF-2 expression was an independent predictor of poor survival.
  
  
  CONCLUSIONS
  Expression of the IGF-2 gene is significantly higher in ovarian cancers relative to normal ovarian surface epithelium. Further, high IGF-2 gene expression is associated with high grade, advanced stage disease, and is an independent predictor of poor survival in patients with epithelial ovarian cancer. As such, IGF-2 is a molecular marker and potential therapeutic target for the most aggressive epithelial ovarian cancers.
authors.affiliation: H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, MCC-GYNPROG, Tampa, FL 33612-9497, USA.
authors.forename: Robyn A
authors.initials: RA
authors.lastname: Sayer
authors.forename: Johnathan M
authors.initials: JM
authors.lastname: Lancaster
authors.forename: Jennifer
authors.initials: J
authors.lastname: Pittman
authors.forename: Jonathon
authors.initials: J
authors.lastname: Gray
authors.forename: Regina
authors.initials: R
authors.lastname: Whitaker
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Marks
authors.forename: Andrew
authors.initials: A
authors.lastname: Berchuck
mesh_terms: D018284:Cystadenocarcinoma, Serous / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000096:biosynthesis* / Q000235:genetics; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate
chemical_list: D007335:Insulin-Like Growth Factor II