Research Paper Volume 16, Issue 11 pp 9334—9349

Figure 7. BNIP3(L)-high MCF7 cells show multi-drug resistance to treatment with 4-OH-Tamoxifen and Palbociclib. MCF7 cells stably-transduced with the BNIP3(L)-GFP constructs were subjected to FACS sorting, to isolate the 5% highest GFP (GFP-high) and the 5% lowest GFP (GFP-low) sub-populations. Differential sensitivity of GFP-high and GFP-low subpopulations to 4-OH-Tamoxifen (A) and Palbociclib (B) was evaluated by using the 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 Palbociclib, at the indicated concentrations. The number of mammospheres were quantitated after 5 days. The percentage indicated at the top of the bars represents the decrease of that bar compared with its own untreated control (GFP-high treated compared to GPF-high untreated, and GFP-low treated compared to GFP-low untreated). Data are shown as the mean ± SD (n = 4). Statistical significance was determined using one-way ANOVA, Dunnett’s multiple comparisons test, *p ≤ 0.05, **p ≤ 0.01, ***p < 0.001.