PHGDH as a therapeutic node: Natural modulators from TCM, degradation pathways, and emerging TPD strategies

Phosphoglycerate dehydrogenase (PHGDH) has emerged as a promising therapeutic target due to its critical roles in the pathogenesis of cancer and neurological disorders. Targeting PHGDH holds significant theoretical and translational potential for cancer therapy and the amelioration of cognitive impairments. However, currently available PHGDH inhibitors are limited in number and primarily function through inhibition of the enzyme's catalytic activity. This review systematically summarizes PHGDH modulators identified from traditional Chinese medicine, including both inhibitors and activators, and presents a detailed analysis of their structure-activity relationships (SAR) and mechanisms of action. It also comprehensively outlines the signaling pathways that regulate PHGDH degradation through the ubiquitin-proteasome system and autophagy-lysosome pathway. Importantly, it also discusses emerging targeted protein degradation (TPD) technologies, including PROTACs, LYTACs, AUTACs, and ATTECs. The development of these frontier technologies has opened new pathways for mitigating the limitations of existing inhibitors.