Stable Differences in Intrinsic Mitochondrial Membrane Potential of Tumor Cell Subpopulations Reflect Phenotypic Heterogeneity
Figure 1
Subpopulations of cells within a primary colonic carcinoma cell population exhibit stable differences in intrinsic ΔΨm. (a) The SW480 cell line stained with JC-1 and analyzed by flow cytometry in FL-2. (b) The parental population of SW480 and 149 subcloned cell lines were stained with JC-1, analyzed by flow cytometry, the intrinsic ΔΨm each subcloned line was expressed relative to that of the unselected population of SW480 cells and plotted as a frequency distribution. (c) 13 subcloned cell lines derived from SW480 cells were selected from further study: the intrinsic ΔΨm of subclones “ΔΨmL” range from 0.17 and 0.50 fold lower; subclones “ΔΨmE” equivalent; and subclones “ΔΨmH” from 1.60 to 2.30 fold higher than that of the population of SW480 cells (also see Figure 1(b)). Mean and SEM of multiple ΔΨm determinations made over approximately 1 year. The intrinsic ΔΨm of all of the ΔΨmL subclones are statistically different from all of the ΔΨmH subclones (Bonferroni's Multiple Comparison Test; ).
