Real-time reverse transcription polymerase chain reaction of GRP78 , CRT and ERp29 genes. HL-60 cells were treated with 20 μg/ml ZEA for indicated time of incubation. The levels of mRNA were normalized to the level of GAPDH mRNA. After the normalization, the mRNA level was expressed as the fold change compared to that in the basal group untreated with ZEA (at 0 h). Data are the mean ± S.E.M. of three independent experiments. * p < 0.05 compared to control, # p < 0.01 compared to control.