Research Paper Volume 14, Issue 24 pp 9877—9889
SOX2-high cancer cells exhibit an aggressive phenotype, with increases in stemness, proliferation and invasion, as well as higher metabolic activity and ATP production
Figure 6. SOX2-high MCF7 show resistance to treatment with 4-OH-Tamoxifen, but show higher sensitivity to Doxycycline. MCF7 cells stably-transduced with the SOX2-GFP construct were subjected to FACS sorting to isolate the 5% highest GFP (GFP-high) and the 5% lowest GFP (GFP-low) subpopulations. Differential sensitivity of GFP-high and GFP-low subpopulations to (A) 4-OH-Tamoxifen and (B) Doxycycline at the indicated concentrations was evaluated by a mammosphere assay. The GFP-high and GFP-low subpopulations were plated in low-attachment plates for mammosphere assays and incubated with 4-OH-Tamoxifen or Doxycycline at the indicated concentrations. The number of mammospheres were analysed after 5 days. The percentage at the top of the bars represent the decrease of that bar compared with its own untreated control (GFP-high treated compare with GPF-high untreated; and GFP-low treated compared with GFP-low untreated). Experiments were performed at least 3 times independently. Results are shown as the mean ± SD: t-test, two tailed-test, *p < 0.05, ** p < 0.01, ***p < 0.001, n.s. not statistically significant.