Fig. 3

p53 is not required for dsP21-322-induced p21 expression. a The p21, p53 and 18S rRNA expression levels were assessed using RT-qPCR in Saos2, MDA-MB-157 and NCI-H1299 cells after dsP21-322, dsControl, or mock transfections. The p21 and p53 expression levels were normalized to that of 18S rRNA and plotted as fold change relative to the mock treatment. The results are expressed as the mean ± S.D. of three independent experiments. b Induction of p21 and p53 protein expression was confirmed using Western blot analysis in Saos2, MDA-MB-157 and NCI-H1299 cells. GAPDH levels were also detected and served as a loading control. c U2-OS and 5637 cells were transfected with 50 nM control siRNA (siCon) or dsP21-322. Combination treatments of dsP21-322 and control siRNA or p53-specific siRNA (sip53) were performed with 50 nM of each RNA duplex. Mock samples were transfected in the absence of dsRNA. Control siRNA consists of scrambled dsRNA based on the p53 siRNA. p21, p53 and 18S rRNA expression levels were assessed using standard RT–qPCR. Data were plotted as the fold change relative to the mock cells. The results are expressed as the mean ± S.D. of three independent experiments. d p53 and p21 protein expression levels were confirmed using immunoblot analysis in U2-OS cells. GAPDH levels were also detected and served as a loading control