Figure 1

DHPM derivatives produce a dose and time dependent cytotoxicity and are selective for tumor cells. A, MCF-7 and MDA-MB-231 cells were treated for 72 h with 4 m, 4bt (dimethylenastron), 4p, 4bc and 4x (100 μM – 1 mM) and cell viability evaluated by the MTT assay. Columns, mean of viable cells; bars, SEM; ***(P < 0.001). B, Fibroblasts were treated with the compounds and concentrations that showed significant activities in breast tumor cells at 72 h and the results compared with those from MCF-7 and MDA-MB-231 cells. Columns, mean of viable cells; bars, SEM; **P < 0.01 and ***P < 0.001 compared with treated fibroblasts. C, MCF-7 and MDA-MB-231 cells were treated with 4 m, 4bt (dimethylenastron), 4p, 4bc and 4x at the maximum non-cytotoxic concentration to normal cells for 24 h, 48 h and 72 h and cell viability evaluated in function of time by the MTT assay. Columns, mean of viable cells; bars, SEM. A, B, C, Data represent the mean ± SEM of three independent experiments in triplicates.