title: miR-503 inhibits cell proliferation and induces apoptosis in colorectal cancer cells by targeting E2F3.
abstract: OBJECTIVE
  Colorectal cancer (CRC) is one of the major healthcare problems worldwide. A lot of miRNAs are aberrantly expressed in CRC and involved in its development and progression. The purpose of this study was to investigate the expression and function of miR-503 in CRC.
  
  
  METHODS
  miR-503 expression was detected in CRC tissues and cell lines by Quantitative real-time PCR. Cell proliferation was assessed by MTT assay. Cell apoptosis and cell cycle distribution were measured by flow cytometry. Moreover, luciferase reporter assay and western blot were performed to determine the potential target of miR-503 in CRC cells.
  
  
  RESULTS
  miR-503 was significantly decreased in CRC tissues and cell lines in comparison with controls. Overexpression of miR-503 in CRC cells remarkably inhibited cell proliferation and induced apoptosis. Furthermore, E2F3 was identified as a direct target of miR-503 in CRC cells and down-regulation of E2F3 had a similar effect as miR-503 overexpression on CRC cells. In addition, the expression of E2F3 was negatively correlated with miR-503 level in CRC tissues.
  
  
  CONCLUSIONS
  miR-503 inhibits cell proliferation and induces apoptosis by directly targeting E2F3 in CRC cells, indicating its potential application in CRC diagnosis and therapy.
authors.affiliation: Department of Surgery, Third Clinical Medical College of Southern Medical University Guangzhou 510630, China ; Department of Surgery, People's Hospital of Hainan Province Haikou 570311, China.
authors.forename: Shun-Wu
authors.initials: SW
authors.lastname: Chang
authors.affiliation: Department of Surgery, People's Hospital of Hainan Province Haikou 570311, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yue
authors.affiliation: Department of Surgery, People's Hospital of Hainan Province Haikou 570311, China.
authors.forename: Bao-Chun
authors.initials: BC
authors.lastname: Wang
authors.affiliation: Department of General Surgery, Fengxian Hospital Affiliated to Southern Medical University Shanghai 201499, China.
authors.forename: Xue-Li
authors.initials: XL
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000235:genetics*; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D015536:Down-Regulation; D050699:E2F3 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000235:genetics
chemical_list: D050699:E2F3 Transcription Factor; C098319:E2F3 protein, human; C545473:MIRN503 microRNA, human; D035683:MicroRNAs
keywords: Colorectal cancer; E2F3; apoptosis; miR-503; proliferation