Luteolin inhibits IGF-I-induced ERK1/2 and CDC25c activation in HT-29 cells. Cells were plated and treated as described in Figure 4. Total lysates were prepared and immunoblot analyses were conducted with antibodies raised against P-ERK1/2, ERK1/2, P-CDC25c, CDC25c, or β-actin. (A) Photographs of the chemiluminescent detection of the blots, which were representative of three independent experiments, were shown. (B, C) The levels of P-ERK1/2 to its own ERK1/2 control band (B) and those of P-CDC25c to its own CDC25c control band (C) on immunoblots were quantified via densitometric scanning of the exposed films, and the control levels (0 μmol/L luteolin, without IGF-I stimulation) were set at 1. Each bar represents the mean ± SEM (n = 3). *Different from 0 μmol/L of luteolin at a stimulation time, P < 0.05.