previously developed and validated LC-MS/MS method. Protein concentration was measured by the Bradford assay and the uptake quantity was expressed as nmol/mg protein. (TIF) Figure S3 p53 and NQO1 protein expression after exposure to TSA. A549 cells were exposed to TSA of gradient concentrations (4, 10, and 40 mM) with or without pretreatment with 10 mM DIC for 30 min. whole cell lysates were prepared and western blot were conducted using anti-p53, anti-NQO1 and anti- GAPDH antibodies. The relative density value of each band is References 1. Ramalingam S, Belanib C (2008) Systemic chemotherapy for advanced non- small cell lung cancer: recent advances and future directions. The Oncologist 13: 5–13. 2. Rudd RM, Gower NH, Spiro SG, Eisen TG, Harper PG, et al. (2005) Gemcitabine plus carboplatin versus mitomycin, ifosfamide, and cisplatin in patients with stage IIIB or IV non-small-cell lung cancer: a phase III randomized study of the London Lung Cancer Group. J Clin Oncol 23: 142–153. 3. 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