title: Multiple Functions of Ten-eleven Translocation 1 during Tumorigenesis.
abstract: OBJECTIVE
  Aberrant expression of ten-eleven translocation 1 (TET1) plays a critical role in tumor development and progression. We systematically summarized the latest research progress on the role and mechanisms of TET1 in cancer biology.
  
  
  METHODS
  Relevant articles published in English from 1980 to April 2016 were selected from the PubMed database. The terms "ten-eleven translocation 1," "5mC," "5hmC," "microRNA," "hypoxia," and "embryonic stem cell" were used for the search.
  
  
  METHODS
  Articles focusing on the role and mechanism of TET1 in tumor were reviewed, including clinical and basic research articles.
  
  
  RESULTS
  TET proteins, the key enzymes converting 5-methylcytosine to 5-hydroxymethylcytosine, play vital roles in DNA demethylation regulation. Recent studies have shown that loss of TET1 is associated with tumorigenesis and can be used as a potential biomarker for cancer therapy, which indicates that TET1 serves as tumor suppressor gene. Moreover, besides its dioxygenase activity, TET1 could induce epithelial-mesenchymal transition and act as a coactivator to regulate gene transcription, such as developmental regulator in embryonic stem cells (ESCs) and hypoxia-responsive gene in cancer. The regulation of TET1 is also correlated with microRNA in a posttranscriptional modification process. Hence, it is complex but critical to comprehend the mechanisms of TET1 in the biology of ESCs and cancer.
  
  
  CONCLUSIONS
  TET1 not only serves as a demethylation enzyme but also plays multiple roles during tumorigenesis and progression. More studies should be carried out to elucidate the exact mechanisms of TET1 and its associations with cancer before considering it as a therapeutic tool.
authors.affiliation: Department of Pathology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058; Key Laboratory of Disease Proteomics of Zhejiang Province, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Tian
authors.affiliation: Department of Epidemiology and Biostatistics, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
authors.forename: Yi-Min
authors.initials: YM
authors.lastname: Zhu
authors.affiliation: Department of Epidemiology and Biostatistics, Zhejiang University School of Public Health, Hangzhou, Zhejiang 310058, China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Sun
authors.affiliation: Department of Pathology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058; Key Laboratory of Disease Proteomics of Zhejiang Province, School of Basic Medical Sciences, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China.
authors.forename: Mao-De
authors.initials: MD
authors.lastname: Lai
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D063646:Carcinogenesis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D035683:MicroRNAs / Q000235:genetics; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D035683:MicroRNAs; D011518:Proto-Oncogene Proteins; D006899:Mixed Function Oxygenases; C462539:TET1 protein, human