Dual‐Stage Light Amplified Photodynamic Therapy against Hypoxic Tumor Based on an O₂ Self‐Sufficient Nanoplatform

Abstract

Tumor hypoxia severely limits the efficacy of traditional photodynamic therapy (PDT). Here, a liposome-based nanoparticle (designated as LipoMB/CaO ) with O self-sufficient property for dual-stage light-driven PDT is demonstrated to address this problem. Through a short time irradiation, O activated by the photosensitizer methylene blue (MB) can induce lipid peroxidation to break the liposome, and enlarge the contact area of CaO with H O, resulting in accelerated O production. Accelerated O level further regulates hypoxic tumor microenvironment and in turn improves O generation by MB under another long time irradiation. In vitro and in vivo experiments also demonstrate the superior competence of LipoMB/CaO to alleviate tumor hypoxia, suppress tumor growth and antitumor metastasis with low side-effect. The O self-sufficient LipoMB/CaO nanoplatform with dual-stage light manipulation is a successful attempt for PDT against hypoxic tumor.

A Mesoporous Nanoenzyme Derived from Metal–Organic Frameworks with Endogenous Oxygen Generation to Alleviate Tumor Hypoxia for Significantly Enhanced Photodynamic Therapy

“…Interestingly, tumors often over‐express hydrogen peroxide (H 2 O 2 , usually at a generation rate of 5 nmol per 10 5 cells h −1 ), and H 2 O 2 could be a source for O 2 production within tumors . Thus, various kinds of nanoparticle‐based catalysts/enzymes have been constructed to catalyze the decomposition of H 2 O 2 to generate O 2 for ameliorating tumor hypoxia, including MnO 2 , CaO 2 , carbon nitride, carbon dots, biological catalase, and others . These reported nanoplatforms have shown outstanding catalytic activity for in situ endogenous O 2 generation, consequently leading to high therapeutic effect on account of the production of highly cytotoxic 1 O 2 under near‐infrared (NIR) light irradiation .…”

Expandable Immunotherapeutic Nanoplatforms Engineered from Cytomembranes of Hybrid Cells Derived from Cancer and Dendritic Cells

“…Intracellular ROS production was next examined by CLSM using 2′,7′‐dichlorofluorescin diacetate (DCFH‐DA) as the ROS probe (Figure E) . The three cytomembrane coated NPs were co‐cultured with cells at the identical dosage of PCN.…”

Fighting Hypoxia to Improve PDT

“…The PDT effect of the battery after NIR irradiation (660 nm, 30 mW•cm −2 , 30 + 60 s) during 15 days (two times each day) led to a better oxygenation and a tumour volume decrease (Figure 24). A liposome-based NP containing MB and the O2 supplier CaO2 were synthetized by Liu et al [137]. After a short irradiation time (30 s), photobleaching of the NPs occurred inducing the formation of O2 by release of CaO2 in water.…”