Figure 4.

Effect of EESP on CDK4 and cyclin D1 expression in HT-29 cells. The cells were treated with the indicated concentrations of EESP for 24 h. (A) The mRNA levels of CDK4 and cyclin D1 were determined using RT-PCR. (B) The protein expression levels of CDK4 and cyclin D1 were analyzed by western blotting. GAPDH and β-actin were used as the internal controls for the RT-PCR and western blotting assays, respectively. The data are representative of three independent experiments. (C and D) Densitometric analysis. The data were normalized to the mean mRNA or protein expression of the untreated control cells (100%).^*P<0.05, vs. the control cells. EESP, ethanol extract of Spica Prunellae; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; CDK4, cyclin-dependent kinase 4.