DNA Nanoflowers Efficiently Encapsulate Photodynamic Agents and CRISPR/Cas9 for Synergistic Pancreatic Cancer Therapy.

Abstract

Photodynamic therapy (PDT) holds significant promise for treating pancreatic cancer by utilizing photosensitizers to generate reactive oxygen species (ROS) that induce tumor cell death. However, the therapeutic efficacy of PDT is hindered by inadequate ROS accumulation. Herein, we develop a DNA nanoflower that enables the controlled codelivery of Cas9 ribonucleoprotein (RNP), hemin, and chlorin e6 for synergistic PDT. The Cas9 RNP selectively knocks out the antioxidant regulator nuclear factor E2-related factor 2 (Nrf2), thereby increasing cancer cells' sensitivity to ROS. Simultaneously, the G-quadruplex/hemin complex catalyzes the conversion of endogenous H₂O₂ into O₂, alleviating tumor hypoxia and supplying additional oxygen for PDT. This synergistic approach substantially amplifies ROS accumulation by attenuating ROS elimination and enhancing ROS generation, demonstrating high gene editing efficiency, significant Nrf2 down-regulation, elevated apoptosis, and remarkable antitumor efficacy in pancreatic cancer cells and a mouse model, underscoring the potential for precision medicine.