For example, the common PIK3CA hotspot mutations in our samples, namely H1047R, E545K and E542K are the targets of pan-PI3K inhibitors such as GDC-0941, BKM120, BYL719 and XL-147 which are being actively evaluated in combination with chemotherapy, endocrine therapy, and/or anti-HER2 agents in advanced breast cancers [14,15]. This evidence concerns the gene PIK3CA and breast cancer.