Fig. 6.

Effect of NQO1 inhibition on 19Ph-DMAG–dependent growth inhibition in human breast cancer cells. MDA468 cells lacking NQO1 activity or isogenic MDA468/NQ16 cells containing human NQO1 were treated with ES936 (100 nM) for 30 minutes to inhibit NQO1 activity prior to 19Ph-DMAG treatment. Growth inhibition with 4-hour 19Ph-DMAG treatment followed by 72-hour drug-free incubation was determined via MTT analysis. Data are expressed as mean ± S.E.M. (n = 4). *P < 0.05 versus same cell type with ES936 pretreatment (two-way analysis of variance with concentration-group interaction for multiple comparisons).