Figure 3.

LTED cells are resistant to the combination of antiestrogens and CDK4/6 inhibitors. (A–D) The growth rates of parental cells (MCF7 and T47D) and their derivatives (MCF7-LTED and T47D-LTED) treated with vehicle, E2 deprivation, 500nM ribociclib or the combination of E2 deprivation and ribociclib and cell number were measured for 12 days and compared to time=0 (start of treatment). Cells were suspended in PBS and counted by a Beckman Coulter Counter. Points represent the mean ± SE of relative number (normalized to t=0) for a single representative experiment performed in triplicate. *p < 0.05, ****p < 0.0001 and ns is not significant (ANOVA) for relative cell number with indicated treatment conditions at 12 days for respective cell lines. Data presented here is representation of three independent experiments (n=3).