To understand the mechanism of action of BKM1644 in PCa cells, we examined the effect of BKM1644 on several known upstream regulators of survivin [27–30] and found that Stat3 phosphorylation at both Tyr705 and Ser727 was significantly reduced upon BKM1644 treatment (Figure 2A). This evidence concerns the gene STAT3 and posterior cortical atrophy.