Effects of NAC on PEITC-induced tubulin reduction in DU145 (A), PC-3 (C), and LNCaP (D) cells. Cells were treated by PEITC (0 or 20 µM), NAC (0 or 5 mM) or PEITC plus NAC for 24 h. ERK1/2 was used as an internal control for protein loading and transfer efficiency, (B), (D), (F) Densitometric measurements of tubulin expression levels were normalized to internal controls and are expressed in relative units