New strategies for targeting PD-1/PD-L1:degraders,bifunctional molecules and covalent inhibitors / 中国药科大学学报

Programmed cell death protein-1(PD-1)/programmed cell death ligand-1(PD-L1)has been considered to be one of the most promising targets for tumor immunotherapy.At present,both monoclonal antibody drugs and small molecule inhibitors targeting PD-1/PD-L1 are facing bottlenecks.Numerous researchers have tried to explore different strategies to block the PD-L1/PD-L1 pathway,hoping to improve the effects of tumor immunotherapy.This review focuses on the degraders,bifunctional molecules and covalent inhibitors that target PD-L1,aiming to provide inspiring insights for the development of anti-PD-1/PD-L1 drugs.

A brief analysis of bifunctional molecules / 药学学报

Selectivity of drug action is a determinant for wide therapeutic window and less adverse response. From the viewpoint of molecular structure the conception and strategy of drug design are mainly embodied in raising selectivity. For the target-based drug discovery it is crucial to precisely obliterate detrimental targets in dimension of time and space, so as to efficaciously translate the in vitro active compounds into in vivo therapeutic medicines. To realize this translation drug molecules must be accurately transported to and destroy the harmful targets. To this end, chemical structures of drugs must be manipulated in multiple dimensions. This article attempts to concisely describe several kinds of bifunctional molecules for raising selectivity from the standpoint of medicinal chemistry. The bifunctionality of antibody-drug conjugates (ADCs) involves in the guidance and carrier of the antibody to guide ADC and reach to target cells, and simultaneously injury quality of the toxin moiety of ADC interacts with and destroys targets. Based upon target 3D structures design of irreversible inhibitors consist in connecting an appropriate electrophilic moiety to a well-defined ligand to endow the molecule with an additional ability to covalently bond to a specific amino acid residue. Hydrophobic tag (HyT), proteosis-targeting chimera (PROTAC), and degradation tag (dTAG) are new developed technologies, which are structurally characterized by bifunctionality, and mechanistically these compounds are capable of recruiting protein of interest (POI), inducing protein-protein interaction (PPI), and cleaving POI. In spite of large molecular size and the bottleneck of pharmacokinetic and physicochemical properties these technologies still have broad development prospect owing to high selectivity and wide adaptations.