While good results are being obtained with the endocrine therapy in patients with tumors expressing ER and/or PR, as well as HER2-targeted therapies used against tumors with HER2 amplification, no efficacious drugs are available for the TNBC, the most aggressive breast neoplasm marked by early relapse and a predominance of distant metastases [3,19]. The gene discussed is PGR; the disease is breast neoplasm.