title: Not all side population cells contain cancer stem-like cells in human gastric cancer cell lines.
abstract: BACKGROUND
  Side population (SP) cells may play a crucial role in tumorigenesis and the recurrence of cancer. Many kinds of cell lines and tissue have demonstrated presence of SP cells including different gastric cancer cell lines. However, is that true all SP cells contain cancer stem-like cells in gastric cancer cell lines?
  
  
  METHODS
  MKN-45 and BGC-823 cells labeled with Hoechst 33342 were chosen to obtain SP cells, then characterized the cancer stem-like properties of SP cells both in vitro and in vivo. Five stemness-related genes expression profiles, including OCT-4, SOX-2, NANOG, CD44 and ATP-binding cassette transporters gene ABCG-2, were tested in SP and MP cells using quantitative real-time RT-PCR. Western blot was chosen to show the difference of protein expression between SP and MP cells. When inoculated into non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, SP cells from MKN-45 showed higher tumorigenesis tendency than MP cells, but SP cells from BGC-823 showed same tumorgenesis tendency as MP cells.
  
  
  CONCLUSIONS
  SP cells from MKN-45 possess cancer stem cell properties and proved that they were gastric cancer stem-like cells. SP cells from BGC-823 didn't possess cancer stem cell properties and proved that not all SP cells contain cancer stem-like cells in gastric cancer cell lines.
authors.affiliation: Department of General Surgery, General Hospital of Chinese People's Liberation Army (PLA), Beijing, 100853, People's Republic of China.
authors.forename: Haihong
authors.initials: H
authors.lastname: Zhang
authors.forename: Hongqing
authors.initials: H
authors.lastname: Xi
authors.forename: Aizhen
authors.initials: A
authors.lastname: Cai
authors.forename: Qijun
authors.initials: Q
authors.lastname: Xia
authors.forename: Xin Xin
authors.initials: XX
authors.lastname: Wang
authors.forename: Canrong
authors.initials: C
authors.lastname: Lu
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Song
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Qinfang
authors.initials: Q
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.forename: Zikuan
authors.initials: Z
authors.lastname: Guo
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000818:Animals; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D051379:Mice; D016688:Mice, Inbred NOD; D009374:Neoplasms, Experimental / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000166:cytology* / Q000502:physiology*; D058985:Side-Population Cells / Q000166:cytology* / Q000502:physiology*; D013274:Stomach Neoplasms / Q000378:metabolism*
chemical_list: D018528:ATP-Binding Cassette Transporters