title: Comparative study on the stem cell phenotypes of C6 cells under different culture conditions.
abstract: BACKGROUND
  Glioma stem cell (GSC) hypothesis posits that a subpopulation of cells within gliomas have true clonogenic and tumorigenic potential. Significantly, a more controversial correlate to GSC is that cells in different culture conditions might display distinct stem cell properties. Considering these possibilities, we applied an approach comparing stem cell characteristics of C6 glioma cells under different culture conditions.
  
  
  METHODS
  C6 cells were cultured under three different growth conditions, i.e., adherent growth in conventional 10% serum medium, non-adherent spheres growth in serum-free medium, as well as adherent growth on laminin-coated flask in serum-free medium. Growth characteristics were detected contrastively through neurosphere formation assay and cell cycle analysis. Markers were determined by immunofluorescence, relative-quantitative reverse transcription (RT)-PCR, Western blotting and flow cytometry. Side population cells were analyzed via flow cytometry. Tumor models were detected by magnetic resonance imaging and hematoxylin & eosin staining. Data analyses were performed with SPSS software (17.0).
  
  
  RESULTS
  C6 cells (C6-Adh, C6-SC-Sph and C6-SC-Adh) showed distinctive growth patterns and proliferation capacity. Compared to suspending C6-SC-Sph, adherent C6-Adh and C6-SC-Adh displayed higher growth ratio. C6-SC-Sph and C6-SC-Adh showed enhanced capability of neurosphere formation and self-renewal. High side population ratio was detected in C6-SC-Sph and C6-SC-Adh. CD133 was not detected in all three kinds of cells. Conversely, Nestin and β-III-tubulin were demonstrated positive, nonetheless with no statistical significance (P > 0.05). Interestingly, lower expression of glial fibrillary acidic protein was demonstrated in C6-SC-Sph and C6-SC-Adh. C6-Adh, C6-SC-Sph and C6-SC-Adh were all displayed in situ oncogenicity, while statistical difference of survival time was not confirmed.
  
  
  CONCLUSIONS
  C6 glioma cell line is endowed with some GSC phenotypes that can be moderately enriched in vitro when transferred into stem cell culture condition. The resultant tumor-spheres may be not a prerequisite or sound source of GSCs and adherent culture in stem cell medium is not a growth condition in favor of GSCs expanding in vivo.
authors: Department of Neurosurgery and Neuro-Oncology Molecular Biology Laboratory, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
authors: Suo-Jun
authors: SJ
authors: Zhang
authors: Fei
authors: F
authors: Ye
authors: Rui-Fan
authors: RF
authors: Xie
authors: Feng
authors: F
authors: Hu
authors: Bao-Feng
authors: BF
authors: Wang
authors: Feng
authors: F
authors: Wan
authors: Dong-Sheng
authors: DS
authors: Guo
authors: Ting
authors: T
authors: Lei
mesh_terms: D000818:Animals; D003470:Culture Media; D005910:Glioma / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D014411:Neoplastic Stem Cells / Q000502:physiology*; D010641:Phenotype; D014407:Tumor Cells, Cultured
chemical_list: D003470:Culture Media