Shortly afterwards, our group reported on yet another slightly more potent competitive PRODH inhibitor, S-5-oxo-2-tetrahydrofurancarboxylic acid (S-5-oxo); and based on structural studies from Tanner’s group (White et al. 2008; Srivastava et al. 2010) we synthesized a mechanism-based covalent inactivator of PRODH, N-propargylglycine (N-PPG), demonstrating its well tolerated systemic activity upon oral administration and its anticancer activity against a variety of human breast cancer models (Scott et al. 2019). The gene discussed is PRODH; the disease is breast cancer.