Mitochondrial dynamics and energy metabolism interference therapy for promoting photothermal sensitization

Abstract

Photothermal therapy (PTT) is minimally invasive, precisely controlled, and therapeutically effective treatment method. However, its efficacy is limited by the overexpression of heat shock proteins (HSP), which leads to cellular thermal blockade. Targeting mitochondria with PTT can enhance anticancer efficacy, as mitochondria encode genes related to HSP and provide energy for their production. Nevertheless, mitochondrial dynamics confer resistance to damage from external stimuli. Therefore, disrupting the balance of mitochondrial dynamics is essential to impede HSP production. Herein, we synthesized degradable Cu₃BiS₃ (CBS) nanosheets (NSs) with one face modified by carboxylated triphenylphosphonium (TPP) to target mitochondria. This modification increases the production of exogenous reactive oxygen species (ROS) and induces the overexpression of dynamin-related protein 1 (Drp1), disrupting mitochondrial dynamic homeostasis. The other face was modified with carboxylated β-cyclodextrin (CD) to load the glycolysis inhibitor (2-deoxyglucose, 2DG), thereby reducing adenosine triphosphate (ATP) production in the extra-mitochondrial space, as glycolysis also occurs in the cytoplasm. The resulting TPP-CBS-2DG Janus NSs (JNSs) not only disrupt mitochondrial energy production, leading to cell starvation, but also inhibit HSP production. Consequently, TPP-CBS-2DG JNSs can enhance tumor thermal sensitivity in PTT, improving its efficacy. This work holds great promise for overcoming tumor heat resistance in PTT and provides a feasible method for fabricating selectively modified multifunctional NSs.