Autophagy-Activated Self-reporting Photosensitizer Promoting Cell Mortality in Cancer Starvation Therapy

Abstract

Cancer starvation therapy have received continuous attention as an efficient method to fight against wide-spectrum cancer. However, during cancer starvation therapy, the protective autophagy promotes cancer cells survival, compromising the therapeutic effect. Herein, a novel strategy by combination of autophagy-activated fluorescent photosensitizers (PSs) and cancer starvation therapy to realize the controllable and efficient ablation of tumor is conceived. Two dual-emissive self-reporting aggregation-induced emission luminogens (AIEgens), TPAQ and TPAP, with autophagy-activated reactive oxygen species (ROS) generation are prepared to fight against the protective autophagy in cancer starvation therapy. When protective autophagy occurs, a portion of TPAQ and TPAP will translocate from lipid droplets to acidic lysosomes with significant redshift in fluorescence emission and enhanced ROS generation ability. The accumulation of ROS induced by TPAQ-H and TPAP-H causes lysosomal membrane permeabilization (LMP), which further results in cell apoptosis and promotes cell death. In addition, TPAQ and TPAP can enable the real-time self-reporting to cell autophagy and cell death process by observing the change of red-emissive fluorescence signals. Particularly, the efficient ablation of tumor via the combination of cancer starvation therapy and photodynamic therapy (PDT) induced by TPAQ has been successfully confirmed in 3D tumor spheroid chip, suggesting the validation of this strategy.

Keywords: 3D tumor spheroid chip; autophagy-activated photosensitizer; cancer starvation therapy; dual-emissive self-reporting AIEgen; photodynamic therapy.