Silencing of p53 and overexpression of p65 diminish the effect of NAC on PDK1 promoter activity and protein expression. A-B, A549 cells (1 × 105 cells) were cotransfected with a wild type PDK1 promoter construct and an internal control phRL-TK Renilla Luciferase Reporter Vector, and control or p53 siRNA (100 nM) for 40 h (A) or co-transfected with control or pCMV6 p65 expression vector (B) for 24 h, followed by NAC for an additional 24 h. Afterwards, luciferase assays were performed to detect PDK1 promoter activity. C-D, A549 cells were transfected with control or p53 siRNA (100 nM) for 40 h (C), and control or p65 overexpression vector for 24 h (D), followed by NAC for an additional 24 h. Afterwards, Western blot was performed to detect p53, p65 and PDK1 proteins. The bar graphs represent the mean ± SD of PDK1/GAPDH of at least three independent experiments. *indicates significance as compared with controls (CTR). **indicates significance of combination treatment as compared with NAC alone (p < 0.05).