Fig. 1

LTED cell lines are refractory to the addition of exogenous E2. a wt and LTED cell lines were treated for 6 days with escalating concentration of E2. Proliferation was expressed as the fold-change relative to vehicle-treated control. Data shown are representative of three independent biological experiments with eight replicates per treatment. Bars: ± SEM. b Western blot analysis assessing ER expression in wt cell lines versus their LTED derivatives. T47D and ZR75.1 lost ER expression, whilst MCF7, SUM44 and HCC1428 retained ER expression. c Schematic representation of the triangular pairwise comparison of this study and a diagram depicting the temporal harvesting of samples during acquisition of resistance. d Protein profile graph depicting differentially abundant proteins between wt-MCF7 and the MCF7 LTED using dimethyl labelling. E2 estradiol, LTED, long-term estrogen deprivation, wt wild type