Simultaneous and Real-Time Imaging of Mitochondrial and Lysosomal ATP with Inducible Excessive Mitophagy for Antitumor Therapy via a Multifunctional Fluorescent Probe

Abstract

Mitophagy is essential for mitochondrial quality control and cellular homeostasis, while its aberrant hyperactivation has emerged as a promising strategy to selectively eliminate cancer cells. This process depends on the adenosine triphosphate (ATP) interplay between mitochondria and lysosomes, yet probes that simultaneously enable dual-organelle ATP imaging and mitophagy regulation are still lacking. Herein, we report MLA, a powerful fluorescent probe that integrates spectrally resolved ATP imaging in both organelles with inducible excessive mitophagy. Bearing pH-adapted fluorophores and a glutathione (GSH)-cleavable disulfide, MLA operates in two modes: at low doses, it serves as a biocompatible reporter to map ATP fluctuations under various perturbations; at high doses, it depletes mitochondrial GSH, thereby triggering a reactive oxygen species (ROS) burst that induces excessive mitophagy and cancer cell death. Mechanistically, it was discovered that this process consumes the transmembrane glycoprotein Mucin 1 (MUC1) whose degradation blocks autophagic flux, and thus leads to lethal accumulation of undegraded autophagosomes, markedly suppressing proliferation. In vivo, MLA enables specific imaging of intratumoral ATP and exhibits tumor-inhibitory capacity. Co-administration with the ATP synthase inhibitor oligomycin A (Omy A) further amplifies the tumor-suppressive effect, validating a simultaneous and drastic ATP/GSH dual-depletion strategy as a feasible combination therapy. MLA represents the first fluorescent probe to synergize dual-organelle ATP imaging with mitophagy regulation, offering a powerful tool for fundamental research and a new paradigm for the design of versatile fluorescent probes.