Endoplasmic reticulum and mitochondrial double-targeted NIR photosensitizer synergistically promote tumor cell death

The excessive production of reactive oxygen species (ROS) can damage the mitochondrial membrane and induce apoptosis, causing endoplasmic reticulum stress and triggering immunogenic cell death. Therefore, the combination of apoptosis and immunogenic death by the dual-targeted ROS generator has great potential to address inefficient cancer treatment. A near-infrared photosensitizer was developed for efficient ROS production and dual-targeted cancer treatment. Due to the modulation of electron structure, the reduced transition energy barrier affords TCy5-I-3F the highest efficiency to produce ROS. TCy5-I-3F has excellent mitochondrial and endoplasmic reticulum targeting ability, causing cell apoptosis and stress of the endoplasmic reticulum for destroying cancer cells. In the dual-targeted mode, high expression of GRP780, activation of heat shock protein (HSP70), the outflow of high mobility group protein B1, efflux of Calreticulin, and massive efflux of adenosine triphosphate are evaluated in the pharmacological experiments. In vivo experiments, the maturation of dendritic cells (DC, CD80+, CD86+), CD8+ T cells and CD3+ T cells also highlights the effectiveness. The tumors of mice treated with TCy5-I-3F and near-infrared (NIR) light are significantly inhibited. The multifunctional targeting design and corresponding mechanisms prove a new insight for exploring efficient photodynamic therapy drugs.