PIK3CA and colorectal cancer: Concomitant mutations in APC that are observed in most cell lines with BRAF mutations with or without PIK3CA mutations, as well as the fact that CTNNB1 gene, encoding for β-catenin, is a recurrent preferential essential gene in these cell lines suggest that BRAF mutated colorectal cancers remain dependent on the activity of WNT/APC/β-catenin pathway [48,49].