PIK3CA and central nervous system cancer: VEGFA, a key proangiogenic factor, is modulated by hsa-miR-26a-5p through pathways such as PI3K/Akt/HIF-1α, influencing tumor angiogenesis in glioma and hepatocellular carcinoma (HCC) (Chai et al., 2013; Qian et al., 2013 ).