title: Loss of Programmed cell death 4 (Pdcd4) associates with the progression of ovarian cancer.
abstract: BACKGROUND
  Programmed cell death 4 (Pdcd4) is a novel tumour suppressor and originally identified as a neoplastic transformation inhibitor. The aim of this study was to investigate the expression, prognostic significance and potential function of Pdcd4 in ovarian cancer.
  
  
  RESULTS
  The expression of Pdcd4 was examined in 30 normal ovarian tissues, 16 borderline and 93 malignant ovarian tissues. A continuous down regulation of Pdcd4 expression in the sequence of normal, borderline and malignant tissues was observed. The expressions of Pdcd4 in both ovarian borderline tissues and carcinomas were significantly lower than the expression in normal ovarian tissues (p < 0.001). Furthermore, patients with lower Pdcd4 expressions were found to have shorter disease-free survival (p = 0.037). The expression of Pdcd4 was also assessed by immunohistochemical analysis in 13 ovarian normal tissues and 44 carcinomas. Different subcellular localization of Pdcd4 was observed in normal compared to malignant cells. Predominant nuclear localization of Pdcd4 was found in normal ovarian tissues while ovarian carcinomas showed mainly cytoplasmic localization of Pdcd4.
  
  
  CONCLUSIONS
  Our study demonstrated that the loss of Pdcd4 was a common abnormality at molecular level in ovarian cancer and it might be a potential prognostic factor in ovarian cancer patients.
authors.affiliation: Department of Obstetrics & Gynaecology, Queen Mary Hospital, University of Hong Kong, Hong Kong, PR China. h0299984@hkusua.hku.hk
authors.forename: N A
authors.initials: NA
authors.lastname: Wei
authors.forename: Stephanie S
authors.initials: SS
authors.lastname: Liu
authors.forename: Thomas H Y
authors.initials: TH
authors.lastname: Leung
authors.forename: Kar F
authors.initials: KF
authors.lastname: Tam
authors.forename: Xiao Y
authors.initials: XY
authors.lastname: Liao
authors.forename: Annie N Y
authors.initials: AN
authors.lastname: Cheung
authors.forename: Karen K L
authors.initials: KK
authors.lastname: Chan
authors.forename: Hextan Y S
authors.initials: HY
authors.lastname: Ngan
mesh_terms: D000328:Adult; D000368:Aged; D051017:Apoptosis Regulatory Proteins / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D010053:Ovary / Q000166:cytology / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D051017:Apoptosis Regulatory Proteins; C114487:PDCD4 protein, human; D016601:RNA-Binding Proteins