Discovery of Novel Drug-like PHGDH Inhibitors to Disrupt Serine Biosynthesis for Cancer Therapy
Dingding Gao, Shuai Tang, Yixin Cen, Liang Yuan, Xiaojing Lan, Qinghua Li, Guo‐Qiang Lin, Min Huang, Ping Tian
Abstract
Being the rate-limiting enzyme within the serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH) is abnormally overexpressed in numerous malignant tumor cells and is a promising target for cancer treatment. Here, we report a series of novel PHGDH inhibitors using a focused compound screening and structural optimization approach. The lead compound D8 displayed good enzymatic inhibitory activity (IC 50 = 2.8 ± 0.1 μM), high binding affinity ( K d = 2.33 μM), and sensitivity to the cell lines with the PHGDH gene amplification or overexpression. Furthermore, D8 was proven to restrict the de novo serine synthesis from glucose within MDA-MB-468 cells. X-ray crystallographic analysis, molecular dynamics simulations, and mutagenesis experiments on PHGDH revealed the binding site at D175 inside the NAD + -binding pocket. Finally, D8 exhibited excellent in vivo pharmacokinetic properties ( F = 82.0%) and exerted evident antitumor efficacy in the PC9 xenograft mouse model.