Our 2016 report in Oncogene[2] was the first to document D1R overexpression in BC, to identify its coupling to the cGMP/PKG apoptotic pathway, and to demonstrate the efficacy of D1R activators in the induction of apoptosis in cultured BCC, and the suppression of BC xenografts in athymic mice. The gene discussed is PRKG1; the disease is breast cancer.