title: LowPLCE1levels are correlated with poor prognosis in hepatocellular carcinoma.
abstract: BACKGROUND
  Previous reports show that phospholipase C epsilon-1 (PLCE1) expression is positively correlated with esophageal squamous cell carcinoma and gastric cardia adenocarcinomas; however, the expression ofPLCE1in hepatocellular carcinoma (HCC) and its correlation with clinical outcome still remain unclear. The aim of this study was to explore the expression ofPLCE1in HCC tissue and to determine whetherPLCE1was a prognostic factor for HCC patients.
  
  
  METHODS
  PLCE1levels in 20 paired HCC tissues and corresponding paracarcinomatous tissues was investigated by quantitative real-time polymerase chain reaction and Western blot assays. In addition, protein levels ofPLCE1in one normal liver epithelial cell and four HCC cell lines were examined using Western blot assay. Moreover, immunohistochemistry was applied to determine the expression ofPLCE1in HCC and corresponding surrounding tissues from 90 patients. Statistical analyses were used to examine the association betweenPLCE1levels and clinicopathological features.
  
  
  RESULTS
  We found that the expression ofPLCE1in tumor tissues was significantly lower than those in paracarcinomatous tissues at both mRNA and protein levels (P<0.05). We also determined thatPLCE1protein expression levels were lower in HCC cell lines than normal liver epithelial cells (P<0.05). Notably, immunohistochemical assay showed thatPLCE1expression was significantly low in HCC tissues compared with the adjacent normal liver tissues (40% vs 18.9%;P<0.05). Besides,PLCE1levels were negatively correlated with tumor capsulae, vascular invasion, Edmondson grade, alpha-fetoprotein, and tumor-node-metastasis stage (P<0.05). Univariate analysis revealed that lower level expression ofPLCE1was significantly associated with poorer overall survival (OS) rate (P<0.001) and disease-free survival rate (P<0.001). Multivariate analysis revealed that lowPLCE1level was an independent poor prognostic factor of OS and recurrence-free survival (P<0.001 andP=0.003, respectively).
  
  
  CONCLUSIONS
  In brief, our results revealed that decreasedPLCE1expression was associated with tumor progression in HCC and may function as a promising biomarker for HCC prognosis.
authors.affiliation: Department of General Surgery, Affiliated Provincial Hospital, Anhui Medical University; Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery.
authors.forename: Ya
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery; CAS Key Laboratory of Innate Immunity and Chronic Disease, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, People's Republic of China.
authors.forename: Song-Ge
authors.initials: SG
authors.lastname: Xing
authors.affiliation: Department of General Surgery, Affiliated Provincial Hospital, Anhui Medical University; Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Jia
authors.affiliation: Department of General Surgery, Affiliated Provincial Hospital, Anhui Medical University; Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery.
authors.forename: Mei
authors.initials: M
authors.lastname: Huang
authors.affiliation: Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery.
authors.forename: Na-Na
authors.initials: NN
authors.lastname: Bian
keywords: PLCE1; hepatocellular carcinoma; immunohistochemistry; prognosis