title: Decreased miR-503 expression in gastric cancer is inversely correlated with serum carcinoembryonic antigen and acts as a potential prognostic and diagnostic biomarker.
abstract: BACKGROUND
  Altered expression of miR-503 has been linked to human carcinogenesis. In this present study, we aimed to detect the potential for miR-503 as a novel biomarker for gastric cancer (GC) patients.
  
  
  METHODS
  The relative mRNA level of miR-503 in serum and tissue of 68 GC patients and serum of 32 healthy volunteers was determined by real-time reverse transcription quantitative polymerase chain reaction.
  
  
  RESULTS
  The miR-503 level was significantly lower in the tissue and serum of GC than their counterparts (allP<0.01). Downregulation of miR-503 was found to be corrected with more aggressive tumor. Patients in the high-miR-503 group showed significantly better overall survival compared to the low-miR-503 group (P=0.021). The serum miR-503 level in GC was inversely correlated with carcinoembryonic antigen (CEA) (r=-0.624,P<0.001). Furthermore, the area under the receiver operating characteristic curve for miR-503 discriminating GC patients from healthy individuals was 0.889 (P=0.006), with a sensitivity of 96.8% and a specificity of 79.4%, higher than that of CEA (area under the receiver operating characteristic curve =0.681,P=0.048).
  
  
  CONCLUSIONS
  The present study suggests that the expression level of miR-503 may serve as prognostic and diagnostic biomarker for GC.
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Daoyi
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Gaojian
authors.initials: G
authors.lastname: Cao
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Zhenfeng
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Jin
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Haowei
authors.initials: H
authors.lastname: Hu
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yu
authors.affiliation: Department of Gastrointestinal Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Ruian, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zeng
keywords: biomarker; diagnosis; gastric cancer; microRNA; prognosis