title: [Altered expressions of embryonic stem-related genes in pancreatic cancer stem cell].
abstract: OBJECTIVE
  To explore the altered expressions of embryonic stem-related genes Oct4 and Nanog in pancreatic cancer stem cells (CSCs).
  
  
  METHODS
  The uni-cell suspension of human pancreatic cancer cell line PANC-1 was prepared and incubated with CD24 and CD44 antibodies. Flow cytometer was used to separate CD24(+)CD44(+) pancreatic cancer stem cells. Tumor cell spheres were observed under light microscope. Then CSCs were induced to differentiate with 10% fetal bovine serum and the expressions of CD24 and CD44 re-evaluated by flow cytometer. Finally the cells were divided into 2 groups, group 1: CD24(+)CD44(+) and group 2: non-separated group. RT-PCR (reverse transcription-polymerase chain reaction) and Q-PCR (quantitative-polymerase chain reaction) were used to examine the transcriptions of Oct4 and Nanog in CSCs. The immunofluorescence was employed to examine the expressions of Oct4 and Nanog. Chemo-sensitivity to gemcitabine was determined by CCK8 assay in each group.
  
  
  RESULTS
  About 1%-3% CD24(+)CD44(+) CSCs were separated from cell line PANC-1. The sorted cells were cultured in a stem cell culture medium to observe the spheroid-forming capacity. And they showed a higher colony-forming efficiency than the unsorted cells [(122 ± 6)‰, P < 0.05]. When cultured in medium with serum, these cells gradually returned to the status of parental cells with a low expression of CD24 and CD44. Both Oct4 and Nanog were highly expressed in CD24(+)CD44(+) stem cells. And the CD24(+)CD44(+) subgroup demonstrated a higher resistance to gemcitabine.
  
  
  CONCLUSIONS
  Subpopulation cells CD44(+)CD24(+) have the properties of tumor stem cells. The up-regulated levels of Oct4 and Nanog may be highly correlated with the multi-potency and a higher drug-resistance of pancreatic CSCs.
authors.affiliation: Department of General Surgery, Affiliated Hospital of Nantong University, Nantong, China.
authors.forename: Yu-hua
authors.initials: YH
authors.lastname: Lu
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.forename: Zhi-wei
authors.initials: ZW
authors.lastname: Wang
authors.forename: Xiang-jun
authors.initials: XJ
authors.lastname: Fan
authors.forename: Sha-jun
authors.initials: SJ
authors.lastname: Zhu
authors.forename: Xiao-hong
authors.initials: XH
authors.lastname: Li
authors.forename: Yao
authors.initials: Y
authors.lastname: Wang
authors.forename: Jun-jie
authors.initials: JJ
authors.lastname: Lu
authors.forename: Ming-yan
authors.initials: MY
authors.lastname: Zhu
mesh_terms: D051927:CD24 Antigen / Q000378:metabolism; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D015870:Gene Expression; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D000071317:Nanog Homeobox Protein; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D050814:Octamer Transcription Factor-3 / Q000235:genetics*; D010190:Pancreatic Neoplasms / Q000378:metabolism*
chemical_list: D051927:CD24 Antigen; D018398:Homeodomain Proteins; D018960:Hyaluronan Receptors; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human