Renilla luciferase activity and TNF-α mRNA expression in TNF-α targeted and non-targeted reporter cell lines. (a) Basal R-Luc reporter activity and TNF-α mRNA levels in the TNF-α targeted (Tg) cell line and in four non-targeted (nTg #1–4) cell lines. (b) Relative R-Luc activity in the targeted cell line (Tg) and in four non-targeted cell lines following treatment with the TNF-α transcriptional activator PMA (5 ng/ml), DOX (5 μM), TSA (100 ng/ml) or Aza-dC (5 mg/ml). (c) The drug-induction profiles of R-Luc activity (top), TNF-α mRNA expression (middle), and R-Luc mRNA expression (bottom) in the Tg cell line. Values represent the mean (+/-SEM, N = 4).