PIK3CA and cancer: The drug panel used for response screening included 48 anti-cancer compounds of seven classes targeting angiogenesis (n = 3), the cell cycle (n = 8), DNA damage (n = 6), MAPK (n = 3), PI3K/AKT/mTOR (n = 3), protein tyrosine kinase (n = 7), and others (n = 18; see Additional file 2, Table S2).