Figure 3.

SPMI-HIF2-1 induced atypical degradation of both MDM2 and MDMX. SPMI-HIF2-1 increased the protein levels of both MDM2 and MDMX at concentrations below 20 µM and promoted target protein degradation in a dose-dependent manner at concentrations ranging from 20 to 100 µM. MCF-7 cells were treated with PMI-HIF1-1 and SPMI-HIF2-1 at various concentrations and the protein levels of MDM2, MDMX, p53, and p21 were analyzed by western blot analysis. Data are shown as the mean ± SEM of three independent experiments. P-values were calculated using the t-test (*P < 0.05; **P < 0.01).