PIK3CA and cancer: Patients carrying a PIK3CA mutation have a higher rate of disease relapse than patients lacking p110α mutations.8 Moreover, it has been reported that these mutations cause a gain of enzymatic fun,3,4 which in terms of cancer cell survival, may depend on the type of p110α mutations.5,6 These cancer-specific mutations in class IA PI3Ks are located in two specific ‘hotspot’ regions: in the helical domain or in the kinase domain of the p110α catalytic subunit.