Inhibition of the Wnt pathway by SFRP2 reduced mCSCs’ resistance to H₂O₂-induced apoptosis.

<p>(A) Total mRNA was isolated from mCSCs treated with a range of concentrations of the SFRP2 protein (0, 3, 10, 15, 20, 50, 100 and 150 nM) for 24 h in serum-free medium. Real-time PCR was performed to quantify Wnt1 mRNA. (B) Representative annexin V/PI flow cytometry analysis of mCSCs. (C) Analysis of annexinV⁺/PI⁻ and annexin V⁺/PI⁺ mCSCs by flow cytometry. (D) Representative immunoblot images of cleaved caspase 3 and p-GSK3β proteins. Caspase 3 was activated after H₂O₂ treatment, but was decreased in C3-CSCs. (E) Densitometric analysis of cleaved caspase 3 protein from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058883#pone-0058883-g004" target="_blank">Figure 4D</a>. (F) Densitometric analysis of p-GSK3β protein from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058883#pone-0058883-g004" target="_blank">Figure 4D</a>. (G) Representative immunoblot images of β-catenin proteins. (H) Densitometric analysis of β-catenin protein from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058883#pone-0058883-g004" target="_blank">Figure 4G</a>. (C, E, F and H) Bar graphs represent the mean values of triplicate measurements ± SD. *P<0.01 vs. the C3-CSCs group; #P<0.01, vs. SFRP2+Wnt1-CSCs.