title: [The tumorigenicity of immortalized cells differentiated from mouse embryonic stem cells].
abstract: OBJECTIVE
  To discuss the tumorigenicity of immortalized endothelial cells differentiated from embryonic stem cells.
  
  
  METHODS
  The embryoid bodies (EB) formed in vitro from embryonic stem cells, were induced to differentiate into many "round cells" (the precursor of endothelial cells). These "round cells" later formed the vascular tube-like structures. To immortalize these cells, human telomerase reverse transcriptase (hTERT) cDNA was transfected into "round cells" by lipofectin, RT-PCR and immunocytochemistry were used to evaluate the immortalized cells. And the tumorigenicity of these cells were evaluated by being injected into nude mice subcutaneously.
  
  
  RESULTS
  95% of these transfected cells expressed Flk-1, CD34 and vWF, and could proliferate in large quantity in vitro (cell number was doubled in 2 days, and increased 12 times in 3 days), and were able to form tubular structures.
  
  
  CONCLUSIONS
  These results suggest that hTERT cDNA transfection can immortalize induced endothelial cells and tumorigenicity is found after immortalized cells are injected into nude mice subcutaneously.
authors.affiliation: Department of Plastic and Reconstructive Surgery, 2nd Affiliated Hospital, Nanjing Medical University, Nanjing 210003, China.
authors.forename: Gan
authors.initials: G
authors.lastname: Shen
authors.forename: Xiao-Qian
authors.initials: XQ
authors.lastname: Cong
mesh_terms: D000818:Animals; D015197:Carcinogenicity Tests; D002454:Cell Differentiation; D002478:Cells, Cultured; D053595:Embryonic Stem Cells / Q000166:cytology*; D042783:Endothelial Cells / Q000166:cytology*; D004730:Endothelium, Vascular / Q000166:cytology; D051379:Mice; D008815:Mice, Inbred Strains; D008819:Mice, Nude; D019098:Telomerase / Q000235:genetics*; D014162:Transfection
chemical_list: C509186:TERT protein, human; D019098:Telomerase