Figure 2.

LTED cells are resistant to CDK4/6 inhibitors. (A–F) The growth rates of parental cells (MCF7 and T47D) and their derivatives (MCF7-LTED and T47D-LTED) were measured in presence of vehicle, palbociclib, ribociclib or abemaciclib for 6 days (media was replenished at 72 h). Cell number was measured by crystal violet assays in 96-wells; absorbance was read at 560 nm. Points represent the mean ± SE of relative number (normalized to 0 nM) for a single representative experiment performed in sextuplicate. **p < 0.01 and ***p < 0.001 (ANOVA) for cell number at indicated drug concentrations compared with 0 nM for indicated cell lines. Data presented here is representation of three independent experiments (n=3).