Treatment of wt-MCF7 and MCF7-LTED cells with escalating concentrations of CXCR7 inhibitor CCX733 with or without exogenous oestradiol. wt-MCF7 cells (A) and MCF7-LTED cells (B) were treated with escalating concentrations of CCX733 for 6 days. Cell survival was measured using CellTiter-Glo. The data are expressed as fold changes relative to vehicle-treated control (0). (C) MCF7-LTED and wt-MCF7 cells were treated with CCX704 as a negative control. CXCR, Chemokine C-X-C receptor; DCC, Dextran-coated charcoal; E2, oestradiol; LTED, Long-term oestrogen deprivation; wt, Wild type. *P<0.05 ** P<0.01, ***P<0.001.