Based on the results of these preclinical studies, many clinical trials were conducted as described in Table 1, NeoPHOEBE (NCT01816594) showed that the HER2-targeted therapy trastuzumab was enhanced when the pan-PI3K inhibitor buparlisib was combined in HER2+ primary breast cancer (Loibl et al., 2017). This evidence concerns the gene PIK3CD and breast cancer.