title: PDCD6 is an independent predictor of progression free survival in epithelial ovarian cancer.
abstract: BACKGROUND
  Programmed cell death 6 (PDCD6) beside its known proapoptotic functions may be a player in survival pathways in cancer. The purpose of this study is to further explore the roles of PDCD6 in epithelial ovarian cancer.
  
  
  METHODS
  Lentiviral vector with shRNA for PDCD6 was used to investigate the effects of PDCD6 knockdown on cell growth, cell cycle, apoptosis and motility in ovarian cancer cells. Two hundred twelve epithelial ovarian cancer tissues were analyzed for mRNA expression of PDCD6 using RT-PCR. Associations of its expression with clinical pathological factors, progression free and overall survival were evaluated.
  
  
  RESULTS
  PDCD6 is highly expressed in metastatic ovarian cancer cells and positively regulates cell migration and invasion. Significantly, the level of PDCD6 expression in epithelial ovarian cancer correlates with clinical progression. Patients with medium or high levels of PDCD6 mRNA were at higher risk for disease progression, compared to those with low levels (HR, 1.29; P = 0.024 for medium levels; and HR, 1.57; P = 0.045 for high levels) after adjusting for age, disease stage, tumor grade, histologic type and residual tumor size. Kaplan-Meier survival analysis demonstrated similar results. However, no association was found between PDCD6 expression and overall survival.
  
  
  CONCLUSIONS
  PDCD6 seems to play an important role in ovarian cancer progression and it may be an independent predictor of progression free survival in epithelial ovarian cancer. Further studies are needed to more completely elucidate the molecular mechanisms of PDCD6 involve in ovarian cancer progression.
authors.affiliation: Center for Genetic and Genomic Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China. shenhuaxu@hotmail.com.
authors.forename: Dan
authors.initials: D
authors.lastname: Su
authors.forename: Haiyan
authors.initials: H
authors.lastname: Xu
authors.forename: Jianguo
authors.initials: J
authors.lastname: Feng
authors.forename: Yun
authors.initials: Y
authors.lastname: Gao
authors.forename: Linhui
authors.initials: L
authors.lastname: Gu
authors.forename: Lisha
authors.initials: L
authors.lastname: Ying
authors.forename: Dionyssios
authors.initials: D
authors.lastname: Katsaros
authors.forename: Herbert
authors.initials: H
authors.lastname: Yu
authors.forename: Shenhua
authors.initials: S
authors.lastname: Xu
authors.forename: Ming
authors.initials: M
authors.lastname: Qi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D000077216:Carcinoma, Ovarian Epithelial; D002453:Cell Cycle; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D053208:Kaplan-Meier Estimate; D016086:Lentivirus / Q000235:genetics; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009375:Neoplasms, Glandular and Epithelial / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D018709:Statistics, Nonparametric; D014162:Transfection
chemical_list: D051017:Apoptosis Regulatory Proteins; D002135:Calcium-Binding Proteins; C097753:PDCD6 protein, human; D012333:RNA, Messenger; D034741:RNA, Small Interfering