Fig. 2.

Effect of PEITC-NAC, DIM and MI, alone or in combination, on the proliferation of DMSO-pretreated HBEC, CSC-pretreated HBEC or A549 cells. (A) HBEC exposed to CSC (5 μg/ml, for 12 weeks, bottom) became elongated fibroblastoid-like cells instead of the normal epithelial cobblestone-like morphology of DMSO-treated HBEC (top). (B) Effect on cell growth. HBEC (treated with DMSO or 5 μg/ml CSC for 12 weeks) were exposed to PEITC-NAC (1 μM), DIM (2 μM) and MI (300 μM), alone or in combination, for 24, 48 and 72 h. A549 cells were treated with higher concentrations of PEITC-NAC (5 μM) and DIM (10 μM), but MI concentration was similar to that used for HBEC (300 μM). Cell proliferation was determined by MTT assay and the results were presented as mean ± SD of the percentage of the control.