Figure 3. Small interfering RNA knockdown of REGγ increases p21 and decreases proliferating cell nuclear antigen (PCNA) protein expression. Total proteins were extracted from parental cells (mock), cells treated with scrambled vector (pSV) and cells treated with proteasome activator (pREGγ). Expression of p21, p27 and PCNA proteins was assessed by Western blot. β-actin was used as an internal control. Data are reported as means ± SD of three independent experiments. ^*P < 0.05 compared to other groups (ANOVA).