Targeting Antitumor Immune Response for Enhancing the Efficacy of Photodynamic Therapy of Cancer: Recent Advances and Future Perspectives

Abstract

Photodynamic therapy (PDT) is a minimally invasive therapeutic strategy for cancer treatment, which can destroy local tumor cells and induce systemic antitumor immune response, whereas, focusing on improving direct cytotoxicity to tumor cells treated by PDT, there is growing interest in developing approaches to further explore the immune stimulatory properties of PDT. In this review we summarize the current knowledge of the innate and adaptive immune responses induced by PDT against tumors, providing evidence showing PDT facilitated-antitumor immunity. Various immunotherapeutic approaches on different cells are reviewed for their effectiveness in improving the treatment efficiency in concert with PDT. Future perspectives are discussed for further enhancing PDT efficiency via intracellular targetable drug delivery as well as optimized experimental model development associated with the study of antitumor immune response.

Porphyrin-based cationic amphiphilic photosensitisers as potential anticancer, antimicrobial and immunosuppressive agents

“…An effective nano-PDT system was constructed from mesoporus silica nanocarriers that were loaded with protoporphyrin IX and an imaging agent (FITC), then derivatised with folate on the phospholipid-capped nanocarriers for selective targeting (Teng et al 2013). Nanomaterials can also be loaded with immunostimulatory agents, together with a PS, to enhance PDT-induced immune responses (Yang et al 2016). However, systemic toxicity associated with nanomaterials is still an issue that needs to be fully addressed to ensure safe and successful clinical translation (Hong et al 2016).…”

Inhibition of IDO leads to IL-6-dependent systemic inflammation in mice when combined with photodynamic therapy

“…PDT is a clinically approved, noninvasive cancer treatment involving generation of cytotoxic reactive oxygen species (ROS) that result from photosensitizer activation by light of appropriate wavelength. PDT leads to direct tumor cell death, disruption of vasculature followed by induction of acute inflammation [8,9]. These events are associated with the release of various inflammatory mediators, recruitment and activation of innate immune cells and subsequent activation of a specific antitumor immune response.…”

Near-Infrared Light-Triggered Photodynamic Therapy and Apoptosis Using Upconversion Nanoparticles With Dual Photosensitizers

“…The damaged or dying tumor cells can be characterized by detecting damage-associated molecular patterns (DAMPs), such as heat shock protein 70 (HSP70) (Korbelik et al, 2005) and high mobility group box 1 (HMGB1) (Panzarini et al, 2013). In particular, HSPs have been known to inhabit in all blood cells and migrate to the cell surface membrane during apoptosis induced by PDT (Zhou et al, 2008;Yang et al, 2016). The expression of HSP70 and HMGB1 protein by PDT was confirmed by western blot.…”

“…The PDT-induced oxidative stress resulted in extended tumor apoptosis (Yang et al, 2016). The damaged or dying tumor cells can be characterized by detecting damage-associated molecular patterns (DAMPs), such as heat shock protein 70 (HSP70) (Korbelik et al, 2005) and high mobility group box 1 (HMGB1) (Panzarini et al, 2013).…”

“…Light-induced local PDT treatment reduces the side effects of normal cell death by administering non-specific anticancer drugs. PDT is also known to induce an immune response by damaged tumor cells, which releases tumor-associated antigens and elicit antitumor immune responses (Maeding et al, 2016;Yang et al, 2016). PDT is usually used to treat local lesions by irradiation with light and the induction of immune responses opens the possibility of treating metastatic tumors or distant sites that cannot be reached by light (Zheng et al, 2016;Xu et al, 2017a;Hwang et al, 2018;Yan et al, 2019).…”