Nano Proteolysis Targeting Chimeras (PROTACs) with Anti‐Hook Effect for Tumor Therapy

Abstract Proteolysis targeting chimera (PROTAC) is an emerging pharmacological modality with innovated post‐translational protein degradation capabilities. However, off‐target induced unintended tissue effects and intrinsic “hook effect” hinder PROTAC biotechnology to be maturely developed. Herein, an intracellular fabricated nano proteolysis targeting chimeras (Nano‐PROTACs) modality with a center‐spoke degradation network for achieving efficient dose‐dependent protein degradation in tumor is reported. The PROTAC precursors are triggered by higher GSH concentrations inside tumor cells, which subsequently in situ self‐assemble into Nano‐PROTACs through intermolecular hydrogen bond interactions. The fibrous Nano‐PROTACs can form effective polynary complexes and E3 ligases degradation network with multi‐binding sites, achieving dose‐dependent protein degradation with “anti‐hook effect”. The generality and efficacy of Nano‐PROTACs are validated by degrading variable protein of interest (POI) such as epidermal growth factor receptor (EGFR) and androgen receptor (AR) in a wide‐range dose‐dependent manner with a 95 % degradation rate and long‐lasting potency up to 72 h in vitro. Significantly, Nano‐PROTACs achieve in vivo dose‐dependent protein degradation up to 79 % and tumor growth inhibition in A549 and LNCap xenograft mice models, respectively. Taking advantages of in situ self‐assembly strategy, the Nano‐PROTACs provide a generalizable platform to promote precise clinical translational application of PROTAC.