Targeted Protein Degradation-mediated Regulation of Tumor Angiogenesis for Anticancer Therapy
- VernacularTitle:靶向蛋白降解调控肿瘤血管生成用于抗肿瘤治疗
- Author:
Yi-Ning ZHAO
1
;
Shi-Yu SONG
1
;
Ying-Qiu QI
2
;
Li WANG
1
Author Information
- Publication Type:Journal Article
- Keywords: targeted protein degradation; PROTAC; LYTAC; tumor angiogenesis; vascular normalization; tumor microenvironment
- From: Progress in Biochemistry and Biophysics 2026;53(10):2596-2608
- CountryChina
- Language:Chinese
- Abstract: Tumor angiogenesis is a core pathological driver of malignant growth, invasion, and metastasis, and represents a major obstacle to effective anticancer therapy. Conventional antiangiogenic agents, including neutralizing monoclonal antibodies and small-molecule tyrosine kinase inhibitors, are constrained by drug resistance, on-target toxicity, and the compensatory activation of alternative pro-angiogenic pathways. Targeted protein degradation (TPD) has emerged as a promising strategy that may overcome these limitations. Unlike traditional inhibitors that operate through an occupancy-driven mechanism, degraders function through an event-driven catalytic mechanism in which a single degrader molecule can catalytically promote the ubiquitination and subsequent proteasomal or lysosomal degradation of multiple molecules of the same target protein, thereby eliminating the target protein together with all of its functions rather than merely blocking a single active site. This review systematically delineates the pathophysiological basis of tumor angiogenesis, encompassing the angiogenic switch driven by hypoxia-inducible factor-1α (HIF-1α), the aberrant structural and functional features of the tumor vasculature, and the self-reinforcing vicious cycles that sustain malignant progression. We then categorize the principal TPD modalities, with particular emphasis on proteolysis-targeting chimeras (PROTACs) and lysosome-targeting chimeras (LYTACs), and describe their design principles and mechanisms of action. PROTACs recruit E3 ubiquitin ligases to direct intracellular targets to the ubiquitin-proteasome system for degradation, whereas LYTACs engage lysosome-targeting receptors to route extracellular and membrane proteins to the lysosome, thereby expanding the degradable target space beyond the intracellular proteome. We further summarize recent advances in the application of TPD to antiangiogenic intervention at four distinct levels. First, at the signaling initiation level, degradation of vascular endothelial growth factor (VEGF) and its receptor vascular endothelial growth factor receptor 2 (VEGFR2) by aptamer-engineered PROTACs, antibody-based LYTACs, and small-molecule VEGFR2 degraders blocks the upstream trigger of the angiogenic cascade. Second, at the signal transduction level, degradation of focal adhesion kinase (FAK), B-Raf proto-oncogene serine/threonine kinase (BRAF), phosphodiesterase 4 (PDE4), and bromodomain-containing protein 4 (BRD4) interrupts intracellular signaling cascades and transcriptional responses. Third, at the microenvironment level, degradation of proviral integration site for Moloney murine leukemia virus (PIM) kinases curtails the pro-angiogenic signals secreted by tumor-associated macrophages. Fourth, multi-target synergistic strategies, exemplified by bispecific degraders that simultaneously target human epidermal growth factor receptor 2 (HER2) and VEGF-A, represent a preliminary exploration of cooperative intervention. Representative degraders reviewed herein elicit diverse antiangiogenic phenotypes, ranging from the direct inhibition of endothelial cell proliferation, migration, and tube formation to reductions in microvessel density and the suppression of vasculogenic mimicry. Finally, we discuss the major challenges that remain, including the precise matching of degradation kinetics with the vascular normalization window, target selectivity and tissue specificity, and the activation of compensatory networks and the emergence of resistance. Since the application of TPD in this setting remains at an early stage, the clinical translation of these approaches will require careful optimization of degradation efficiency, spatiotemporal control, and delivery strategies. We also envision future directions toward immunotherapy-based combination regimens and precision-degradation approaches guided by single-cell and spatial transcriptomics. In our view, TPD should not be regarded merely as a substitute for conventional antiangiogenic drugs, but rather as a molecular tool capable of systematically remodeling the tumor vascular microenvironment. When precise control of degradation efficiency and spatiotemporal regulation are integrated with a thorough understanding of the heterogeneity and compensatory capacity of tumor vessels, the full clinical potential of this strategy can be realized.
