Figure 5
Recombinant hGX sPLA 2 and OA activate the pro-survival Akt kinase and display similar effects in breast cancer cells. (A, B) MDA-MB-231, T-47D and MCF7 cell lines were grown in serum-free medium for 96 h in the presence of the indicated concentrations of OA complexed with 0.5% FAF BSA. LD content was determined by Nile red staining (A) and cell death was assessed in parallel samples using the TMRM/YO-PRO-1 apoptosis assay (B). (C) MDA-MB-231 cells were made quiescent by 48 h serum starvation, then washed and incubated with hGX (10 nM) or OA (100 μM) in serum-free medium for the times indicated. Cell lysates were analyzed for the presence of Ser473-phosphorylated Akt (p-Akt) kinase, total Akt protein and β-actin loading control by immunoblotting. The amount of p-Akt was normalized to total Akt protein and was quantified relative to untreated controls at each specific time point (D). Values on the graphs are means ± SD of at least two experiments performed in duplicate and results that are statistically significant over control samples are indicated (*, P < 0.05; **, P < 0.01; ***, P < 0.001; one-way ANOVA with Bonferroni adjustment).