PIK3CA and cancer: When we choose a more stringent cut-off of p < 10–5, 17 of the 29 (58.6%) positively selected genes are known cancer genes, according to the CGC, and the work of Lawrence et al. [20] and Kandoth et al. [35], such as the well-known cancer drivers TP53, KRAS, PIK3CA, and BRAF. (Supplementary Table 2).