Its translational importance is evidenced by two large randomized trials, BOLERO-2 and TAMRAD, which found a better progression-free survival of HR+ breast cancer with the addition of a TORC1 inhibitor, Everolimus, in patients who had earlier received the aromatase inhibitor Exmestane and showed an initial response but progressed later in the course of therapy [79,80,81]. The gene discussed is CYP19A1; the disease is breast cancer.