Figure 6. Doxorubicin cytotoxicity in resistant MCF-7 cells after treatment with phosphoethanolamine-polyethylenimine complexes at different time lags (h).
MCF-7 resistant and sensitive cells were treated with formulations prepared with siRNA targeting MDR-1 (siMDR-1). Control cells were treated with medium. At different time points post-siMDR-1, cells were treated with doxorubicin (1 µg/ml) for 72 h, and viability was measured. Data are expressed as the mean ± standard deviation (n = 3). p < 0.001 for dioleoylphosphatidylethanolamine-polyethylenimine treatments versus Dox-only treated cells, for all time-points.
Dox: Doxorubicin.