Synergy of hypoxia relief and chromatin remodeling to overcome tumor radiation resistance.

Radiotherapy (RT) is one of the most extensive and effective approaches available for clinical tumor treatment. However, tumor microenvironments including hypoxia and histone deacetylase (HDAC) overexpression could induce radiation resistance, leading to tumor recurrence. Herein, nanoparticles (CAT-SAHA@PLGA) encapsulating catalase and HDAC inhibitor SAHA exhibited protected catalytic activity of catalase and prolonged the pharmacokinetic exposure of the HDAC inhibitor. Overall, the established CAT-SAHA@PLGA nanoparticles could overcome radiation resistance by synergistically increasing tumor oxygenation and inhibiting HDAC activity.