Recent strategies for nano-based PTT combined with immunotherapy: from a biomaterial point of view

Abstract

Cancer has been a great threat to humans for decades. Due to the limitations of monotherapy, combinational therapies such as photothermal therapy (PTT) and immunotherapy have gained increasing attention with expectation to overcome the shortfalls of each other and obtain satisfactory therapeutic outcomes. PTT can inhibit primary tumors by thermal ablation but usually fails to achieve complete eradication and cannot prevent metastasis and recurrence. Meanwhile, the efficacy of immunotherapy is usually attenuated by the weak immunogenicity of tumor and the immunosuppressive tumor microenvironment (ITM). Therefore, many recent studies have attempted to synergize PTT with immunotherapy in order to enhance the therapeutic efficacy. In this review, we aim to summarize the cutting-edge strategies in combining nano-based PTT with immunotherapy for cancer treatment. Herein, the combination strategies were mainly classified into four categories, including 1) nano-based PTT combined with antigens to induce host immune responses; 2) nano-based PTT in combination with immune adjuvants acting as in situ vaccines; 3) nano-based PTT synergized with immune checkpoint blockade or other regulators to relieve the ITM; 4) nano-based PTT combined with CAR-T therapy or cytokine therapy for tumor treatment. The characteristics of various photothermal agents and nanoplatforms as well as the immunological mechanisms for the synergism were also introduced in detail. Finally, we discussed the existing challenges and future prospects in combined PTT and immunotherapy.

Docetaxel-Loaded Novel Nano-Platform for Synergistic Therapy of Non-Small Cell Lung Cancer

“…As expected, the apoptosis ratio of cells treated by MDPMH under laser irradiation was higher than that of other groups, which could probably be attributed to the effect of PTT. Previous studies had confirmed that PTT could further enhance the permeability of the tumor cell membrane and thus improve the internalization of nanoparticles ( Liu et al, 2019 ; Huang et al, 2021 ).…”

Dual Functional Alginate and Collagen-Based Injectable Hydrogel for Treatment of Cancer and Its Metastasis

“…Cancer treatment using hydrogels is being attempted because they can effectively supply drugs. In a recent study, immunostimulatory molecules or immune checkpoint inhibitors were incorporated into hydrogels and showed preventive effects against metastatic cancer [42][43][44][45] . However, when applying the hydrogel, the rst transplanted tumor was surgically removed, and the hydrogel was attached to the surgical site, which effectively prevented second-challenged metastatic cancer growth 42 .…”

Exosome-based delivery nanoplatforms: next-generation theranostic platforms for breast cancer

“…Common photothermal agents include inorganic photothermal agents such as gold nanomaterials and carbon-based materials and organic photothermal agents such as ICG and IR780. 175,176…”

“…Common photothermal agents include inorganic photothermal agents such as gold nanomaterials and carbon-based materials and organic photothermal agents such as ICG and IR780. 175,176 The combined therapeutic strategy of exosome-mimetic nanoparticles with chemotherapy and photothermal therapy represent a new approach to antitumor therapy. Tian et al constructed porous silica nanoparticles (E-MSNs) camouflaged by tumor cellderived exosomes (ID@E-MSNs) coloaded with ICG and DOX to achieve the synergistic treatment of breast cancer with chemotherapy and photothermal therapy.…”