Recent Progress of Copper-Based Nanomaterials in Tumor-Targeted Photothermal Therapy/Photodynamic Therapy

Abstract

Nanotechnology, an emerging and promising therapeutic tool, may improve the effectiveness of phototherapy (PT) in antitumor therapy because of the development of nanomaterials (NMs) with light-absorbing properties. The tumor-targeted PTs, such as photothermal therapy (PTT) and photodynamic therapy (PDT), transform light energy into heat and produce reactive oxygen species (ROS) that accumulate at the tumor site. The increase in ROS levels induces oxidative stress (OS) during carcinogenesis and disease development. Because of the localized surface plasmon resonance (LSPR) feature of copper (Cu), a vital trace element in the human body, Cu-based NMs can exhibit good near-infrared (NIR) absorption and excellent photothermal properties. In the tumor microenvironment (TME), Cu2+ combines with H2O2 to produce O2 that is reduced to Cu1+ by glutathione (GSH), causing a Fenton-like reaction that reduces tumor hypoxia and simultaneously generates ROS to eliminate tumor cells in conjunction with PTT/PDT. Compared with other therapeutic modalities, PTT/PDT can precisely target tumor location to kill tumor cells. Moreover, multiple treatment modalities can be combined with PTT/PDT to treat a tumor using Cu-based NMs. Herein, we reviewed and briefly summarized the mechanisms of actions of tumor-targeted PTT/PDT and the role of Cu, generated from Cu-based NMs, in PTs. Furthermore, we described the Cu-based NMs used in PTT/PDT applications.

Nanomaterials modulate tumor-associated macrophages for the treatment of digestive system tumors

“…However, PDT efficacy is hindered by the hypoxic TME [ 100 ]. To address this issue, copper-based nanomaterials have been investigated because of their favorable NIR light absorption properties and ability to synergize with hydrogen peroxide (H 2 O 2 ) within the TME, resulting in oxygen production and ultimately enhancing PDT efficacy [ 101 ]. Furthermore, CaO 2 nanomaterials generate O 2 and H 2 O 2 while releasing Ca 2+ ions to induce calcium overload and facilitate apoptosis in tumor cells [ 102 ].…”

Transition Metal Oxide Nanomaterials: New Weapons to Boost Anti-Tumor Immunity Cycle

“…In the TME, Cu 2+ binds with H 2 O 2 to generate O 2 , which is then reduced to Cu 1+ by GSH, initiating a Fenton-like reaction. This reduces tumor hypoxia while generating ROS to eliminate tumor cells in conjunction with PTT and PDT, promoting ICD, and enhancing tumor immunogenicity [97]. To further address the issue of inadequate PDT efficiency, copper oxide can be designed into heterogeneous structures and loaded with immunoadjuvants to further amplify its efficacy.…”

“…In addition to enhancing immunogenicity, copper oxide NPs can also reverse tumor immune suppression through ferroptosis and cuproptosis mechanisms [97]. For instance, Ning and colleagues physically extruded a PTC system with AIE photosensitizer (TBP-2), Cu 2 O, and a platelet vesicle (PV).…”