Figure 4.
p27 protein expression is increased by selective inhibition of PFKFB3. HeLa cells were transfected with a control siRNA (Ctrl) or two PFKFB3 siRNA molecules (P31 and P32) and, after 48 h, Cip/Kip family members p57, p27 and p21 were assessed by western blot analysis (a) and densitometry (b). HCT-116 (c, d) and Panc-1 cells (e, f) were similarly transfected with the two PFKFB3 siRNA molecules (P31 and P32) and examined for p27 protein levels by western blot analysis and densitometry. HeLa cells were also separated into cytoplasmic (C) and nuclear (N) fractions, which were then assessed for PFKFB3, p27, Oct-1 (nuclear control) and a-Tubulin (cytoplasmic control) by western blot analysis (g) and densitometry (h). The Hela cells then were examined for cytoplasmic versus nuclear p27 expression by immunofluorescence using DAPI to localize the nuclei (i)