title: A new approach to screening cancer stem cells from the U251 human glioma             cell line based on cell growth state.
abstract: Cancer stem cells (CSCs) play important roles in the biological behaviour             of malignant tumours. To study their properties, they must be carefully identified             and purified. Cancer cells can acquire three different morphological types during             single cell cloning. A small subpopulation of clones acquires a regular and compact             shape, and these clones are enriched for CSCs; however, the majority of clones             have an irregular morphology with loose intercellular junctions, with fewer characteristics             of CSCs. At present, the main method to isolate CSCs is to collect the regular             clones in low-density culture conditions; therefore, an insufficient amount of             CSCs is obtained for clonal expansion. To obtain a more sufficient amount of CSCs,             the clones with an irregular and loose morphology were examined in our study.             We found a small subpopulation of U251 glioma cells that arrested in the suspended             state and that subsequently migrated to form new clones. The suspended cells were             isolated from the irregular and loose clones. Clonogenic assays were performed             in which 43.70% of the suspended cells and 32.91% of the adherent cells formed             new clones. To determine the biological differences between the suspended and             adherent cells, carboxyfluorescein succinimidyl ester (CFSE) labelling, MTT assays,             and cell cycle assays were performed. The results demonstrated that the suspended             cells had the characteristics of CSCs, including higher proliferation rates, as             well as self-maintenance and self-renewal capabilities, and they stained positively             for markers of brain CSCs and had multilineage potential. Thus, we established             a new and efficient approach for screening CSCs from the U251 human glioma cell             line based on the cell growth state.
authors.affiliation: State Key Laboratory of Cancer Biology and Department of Pathology, Xijing Hospital, Fourth Military Medical University, Xi'an, PR China.
authors.forename: Xiangmei
authors.initials: X
authors.lastname: Cao
authors.forename: Yu
authors.initials: Y
authors.lastname: Gu
authors.forename: Lina
authors.initials: L
authors.lastname: Jiang
authors.forename: Yingmei
authors.initials: Y
authors.lastname: Wang
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Yuqiao
authors.initials: Y
authors.lastname: Xu
authors.forename: Junxia
authors.initials: J
authors.lastname: Deng
authors.forename: Yayun
authors.initials: Y
authors.lastname: Nan
authors.forename: Liying
authors.initials: L
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Qing
authors.initials: Q
authors.lastname: Li
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002469:Cell Separation / Q000379:methods; D048430:Cell Shape; D005910:Glioma; D006801:Humans; D014411:Neoplastic Stem Cells / Q000502:physiology*; D018874:Spheroids, Cellular / Q000502:physiology
chemical_list: D014408:Biomarkers, Tumor