Preservation of the 3D Phenotype Upon Dispersal of Cultured Cell Spheroids Into Monolayer Cultures.
In functional cytometric studies, cultured cells are exposed to effectors (e.g., drugs), and the heterogeneity of cell responses are studied using cytometry techniques (e.g., image cytometry). Such studies are difficult to perform on 3D cell cultures. A solution is to disperse 3D clusters and transfer the cells to the 2D state before applying effectors and using cytometry. This approach requires that the lifetime of the 3D phenotype be longer than the duration of the experiment. Here we studied the dynamics of phenotype transformation from 3D to 2D and searched for means of slowing this transformation down in dispersed spheroids of MCF7 cells. We found three functional biomarkers of the 3D phenotype in MCF7 cell spheroids that are absent in the 2D cell culture: (i) the presence of a subpopulation with an elevated drug-expelling capacity; (ii) the presence of a subpopulation with an elevated cytoprotective capacity; and (iii) the accumulation of cells in the G1 phase of the cell cycle. Monitoring these biomarkers in cells transferred from the 3D state to the 2D state revealed their gradual extinction. We found that the combined application of an elevated cell density and thiol-containing medium supplements increased the lifetime of the 3D phenotype by several fold to as long as 96 h. Our results suggest that extending the lifetime of the 3D phenotype in the cells transferred from the 3D state to the 2D state can facilitate detailed functional cytometric studies, such as measurements of population heterogeneity of cytotoxicity, chemosensitivity, and radiosensitivity. J. Cell. Biochem. 118: 154-162, 2017. © 2016 Wiley Periodicals, Inc.
Department of Chemistry and Centre for Research on Biomolecular Interactions, York University, Toronto, Ontario, Canada, M3J 1P3.
Vasilij
V
Koshkin
Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada, N5G 1L7.
Laurie E
LE
Ailles
Department of Medicine, Medical Oncology and Haematology, Princess Margaret Hospital, Toronto, Ontario, Canada, M5G 2C4.
Geoffrey
G
Liu
Department of Chemistry and Centre for Research on Biomolecular Interactions, York University, Toronto, Ontario, Canada, M3J 1P3.
Sergey N
SN
Krylov
D018929:Cell Culture Techniques / Q000379:methods; D005260:Female; D016193:G1 Phase / Q000502:physiology*; D006801:Humans; D061986:MCF-7 Cells; D018874:Spheroids, Cellular / Q000166:cytology* / Q000378:metabolism*
3D CELL CULTURE; CANCER; FUNCTIONAL BIOMARKERS; FUNCTIONAL CYTOMETRIC STUDIES