PIK3CA and neoplasm: Sensitivity to both ipatasertib and taselisib was more evident in HER2+ cell lines and in PI3KCA mutated cell lines, thus confirming previous preclinical studies [48, 56, 60–62], while TNBC cell lines resulted, overall, less sensitive to both drugs, in keeping with previous findings that TNBC tumours are associated with resistance to PI3K/AKT inhibitors [13].