Fig. 1

EE-15-one induces rapid loss of cells in different breast cancer cell lines. a The effect of EE-15-one on MCF-7, MDA-MB-231 and BT-20 cells was analysed by quantifying cell numbers using crystal violet staining 24 h after exposure to a concentration range of 0.5–10 μM EE-15-one. b To determine if EE-15-one had a similar effect on cells as the sulphamoylated ESE-15-one derivative, MCF-7 cells were exposed to a concentration range of either ESE-15-one or EE-15-one and cell number was quantified after 24 h. c To identify the essential structural components of EE-15-one responsible for its activity, closely related derivatives lacking either the ketone group at C17 (EE-15-ol) or the alkene group at C15 (EE-one) were added to MCF-7 cells and cell number was quantified using crystal violet staining. All graphs represent three independent experiments with error bars indicating s.e.m. *Represents significant differences as tested by student’s t-test with P < 0.05