Blocking NF-κB restores elevated Nrf2 levels to normal. (A) THP-1 cells were transfected with 30nM of control, p50 or p65 siRNA, or p50 and p65 combined and incubated for 48 hours. Extracts were separated by SDS-PAGE and Western blot analysis was conducted for p50 and p65 total protein or nuclear protein levels. Blots were reprobed for β-actin and TBP to confirm equal sample loading. (B) THP-1 cells were transfected with 30nM of control, p50 or p65-siRNA, or p50 and p65 combined and incubated for 24, 48, and 72 hours, then examined for the nuclear binding of p65 and p50 to specific κB sites. (C) AML cells were transfected with 30 nM of control, p50, or p65-siRNA, or p50 and p65 combined and incubated for 24 hours. RNA was extracted and examined for Nrf2 mRNA expression by real-time PCR. Data presented as percent of control. *P < .05 between the different treatment groups. (D) THP-1 cells were transfected with 30nM of control, p50 or p65-siRNA, or p50 and p65 combined and incubated for 48 hours. Nuclear and cytosolic extracts were separated by SDS-PAGE and Western blot analysis was conducted for Nrf2 and Keap1 protein levels were measured.