title: Enrichment of breast cancer stem cells using a keratinocyte serum-free medium.
abstract: BACKGROUND
  Keratinocyte serum-free medium (K-SFM) is a defined medium used to support the growth of primary keratinocytes and embryonic stem cell. The aim of this research was to optimize enrichment of breast cancer stem cells (CSCs) using K-SFM.
  
  
  METHODS
  A K-SFM was used to enrich CSCs from two breast cancer cell lines and a primary culture of breast cancer. RPMI-1640 supplemented with 10% fetal calf serum (FCS) was used as a control. CSCs were identified with flow cytometry using CD44(+)/CD24(-) as molecular markers. The expression of a variety of CSC markers (Oct-4, ABCG2, Nanog, N-cadherin, and E-cadherin) was analyzed with real-time PCR.
  
  
  RESULTS
  Much higher percentage of CSCs was achieved with K-SFM: 17.3% for MCF-7 cells, 17.4% for SKBR-3, and 20.0% for primary breast cancer culture. Less than 1% CSC was achieved using RPMI-1640 supplemented with 10% FCS. In comparison to the CSCs obtained with RPMI-1640, CSCs in the K-SFM expressed higher levels of Oct-4, ABCG2, Nanog and N-cadherin, and lower level of E-cadherin.
  
  
  CONCLUSIONS
  K-SFM is an optimal culture medium to maintain and to enrich breast CSCs.
authors: Department of Pathophysiology, Basic Medical College, Zhengzhou University, Zhengzhou, Henan 450053, China.
authors: Zhen-Zhen
authors: ZZ
authors: Liu
authors: Ping
authors: P
authors: Chen
authors: Zhen-Duo
authors: ZD
authors: Lu
authors: Shu-de
authors: SD
authors: Cui
authors: Zi-Ming
authors: ZM
authors: Dong
mesh_terms: D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D015820:Cadherins / Q000235:genetics; D018929:Cell Culture Techniques / Q000379:methods*; D045744:Cell Line, Tumor; D016895:Culture Media, Serum-Free; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D015603:Keratinocytes / Q000166:cytology*; D000071317:Nanog Homeobox Protein; D009363:Neoplasm Proteins / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000166:cytology* / Q000378:metabolism*; D050814:Octamer Transcription Factor-3 / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C116614:ABCG2 protein, human; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D015820:Cadherins; D016895:Culture Media, Serum-Free; D018398:Homeodomain Proteins; C486780:NANOG protein, human; D000071317:Nanog Homeobox Protein; D009363:Neoplasm Proteins; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human