Emerging photodynamic nanotherapeutics for inducing immunogenic cell death and potentiating cancer immunotherapy

Single Component Organic Photosensitizer with NIR-I Emission Realizing Type-I Photodynamic and GSH-Depletion Caused Ferroptosis Synergistic Theranostics

Phototheranostic agents have thrived as prominent tools for tumor luminescence imaging and therapies. Herein, a series of organic photosensitizers (PSs) with donor-acceptors (D-A) are elaborately designed and synthesized. In particular, PPR-2CN exhibits stable near infrared-I (NIR-I) emission, excellent free radicals generation and phototoxicity. Experimental analysis and calculations imply that a small singlet-triplet energy gap (ΔES1-T1 ) and large spin-orbit coupling (SOC) constant boost the intersystem crossing (ISC), leading to type-I photodynamic therapy (PDT). Additionally, the specific glutamate (Glu) and glutathione (GSH) consumption abilities of PPR-2CN inhibit the intracellular biosynthesis of GSH, resulting in redox dyshomeostasis and GSH-depletion causing ferroptosis. This work first realizes that single component organic PS could be simultaneously used as a type-I photodynamic agent and metal-free ferroptosis inducer for NIR-I imaging-guided multimodal synergistic therapy.

Harnessing Nanomaterials for Cancer Sonodynamic Immunotherapy

Immunotherapy has made remarkable strides in cancer therapy over the past decade. However, such emerging therapy still suffers from the low response rates and immune-related adverse events. Various strategies have been developed to overcome these serious challenges. Therein, sonodynamic therapy (SDT), as a non-invasive treatment, has received ever-increasing attention especially in the treatment of deep-seated tumors. Significantly, SDT can effectively induce immunogenic cell death to trigger systemic anti-tumor immune response, termed sonodynamic immunotherapy. The rapid development of nanotechnology has revolutionized SDT effects with robust immune response induction. As a result, more and more innovative nanosonosensitizers and synergistic treatment modalities are established with superior efficacy and safe profile. In this review, the recent advances in cancer sonodynamic immunotherapy are summarized with a particular emphasis on how nanotechnology can be explored to harness SDT for amplifying anti-tumor immune response. Moreover, the current challenges in this field and the prospects for its clinical translation are also presented. It is anticipated that this review can provide rational guidance and facilitate the development of nanomaterials-assisted sonodynamic immunotherapy, helping to pave the way for next-generation cancer therapy and eventually achieve a durable response in patients.

Inorganic nanoparticle-integrated mesenchymal stem cells: A potential biological agent for multifaceted applications

Mesenchymal stem cell (MSC)-based therapies are flourishing. MSCs could be used as potential therapeutic agents for regenerative medicine due to their own repair function. Meanwhile, the natural predisposition toward inflammation or injury sites makes them promising carriers for targeted drug delivery. Inorganic nanoparticles (INPs) are greatly favored for their unique properties and potential applications in biomedical fields. Current research has integrated INPs with MSCs to enhance their regenerative or antitumor functions. This model also allows the in vivo fate tracking of MSCs in multiple imaging modalities, as many INPs are also excellent contrast agents. Thus, INP-integrated MSCs would be a multifunctional biologic agent with great potential. In this review, the current roles performed by the integration of INPs with MSCs, including (i) enhancing their repair and regeneration capacity via the improvement of migration, survival, paracrine, or differentiation properties, (ii) empowering tumor-killing ability through agent loaded or hyperthermia, and (iii) conferring traceability are summarized. An introduction of INP-integrated MSCs for simultaneous treatment and tracking is also included. The promising applications of INP-integrated MSCs in future treatments are emphasized and the challenges to their clinical translation are discussed.

Research development of porphyrin-based metal-organic frameworks: targeting modalities and cancer therapeutic applications

Porphyrins are naturally occurring organic molecules that have attracted widespread attention for their potential in the field of biomedical research. Porphyrin-based metal-organic frameworks (MOFs) that utilize porphyrin molecules as organic ligands have gained attention from researchers due to their excellent results as photosensitizers in tumor photodynamic therapy (PDT). Additionally, MOFs hold significant promise and potential for other tumor therapeutic approaches due to their tunable size and pore size, excellent porosity, and ultra-high specific surface area. Active delivery of nanomaterials via targeted molecules for tumor therapy has demonstrated greater accumulation, lower drug doses, higher therapeutic efficacy, and reduced side effects relative to passive targeting through the enhanced permeation and retention effect (EPR). This paper presents a comprehensive review of the targeting methods employed by porphyrin-based MOFs in tumor targeting therapy over the past few years. It further discusses the applications of porphyrin-based MOFs for targeted cancer therapy through various therapeutic methods. The objective of this paper is to provide a valuable reference and source of ideas for targeted therapy using porphyrin-based MOF materials and to inspire further exploration of their potential in the field of cancer therapy.

Multifunctional Nanoplatform-Mediated Chemo-Photothermal Therapy Combines Immunogenic Cell Death with Checkpoint Blockade to Combat Triple-Negative Breast Cancer and Distant Metastasis

Background

Breast cancer has become the most common cancer in women. Compare with other subtypes of breast cancer, triple-negative breast cancer (TNBC) is more likely to relapse and metastasize. Highly effective therapeutic strategies are desperately needed to be explored. In this study, a multifunctional nanoplatform is expected to mediate chemo-photothermal therapy, which can combine immunogenic cell death with checkpoint blockade to combat TNBC and distant metastasis.

Methods

Poly (lactic acid-glycolic acid)-Poly (ethylene glycol) (PLGA-PEG) nanoparticles (NPs), a type of polymeric NPs, loaded with IR780, a near-infrared (NIR) dye, and doxorubicin (DOX) as the chemotherapeutic drug, were assembled by an improved double emulsification method (designated as IDNPs). The characterization, intracellular uptake, biosafety, photoacoustic (PA) imaging performance, and biodistribution of IDNPs were studied. Chemo-photothermal therapeutic effect and immunogenic cell death (ICD) were evaluated both in vitro and in vivo. The potency of chemo-photothermal therapy-triggered ICD in combination with anti-PD-1 immune checkpoint blockade (ICB) immunotherapy in eliciting immune response and treating distant tumors was further investigated.

Results

IR780 and DOX were successfully loaded into PLGA-PEG to form the IDNPs, with size of 243.87nm and Zeta potential of -6.25mV. The encapsulation efficiency of IR780 and DOX was 83.44% and 5.98%, respectively. IDNPs demonstrated remarkable on-site accumulation and PA imaging capability toward 4T1 TNBC models. Chemo-photothermal therapy demonstrated satisfactory therapeutic effects both in vitro and in vivo, and triggered ICD efficiently. ICD, in combination with anti-PD-1, provoked a systemic antitumor immune response against distant tumors.

Conclusion

Multifunctional IDNPs were successfully synthesized to mediate chemo-photothermal therapy, which combines immunogenic cell death with checkpoint blockade to combat TNBC and distant metastasis, showing great promise preclinically and clinically.

Biomaterials Facilitating Dendritic Cell-Mediated Cancer Immunotherapy

Dendritic cell (DC)-based cancer immunotherapy has exhibited remarkable clinical prospects because DCs play a central role in initiating and regulating adaptive immune responses. However, the application of traditional DC-mediated immunotherapy is limited due to insufficient antigen delivery, inadequate antigen presentation, and high levels of immunosuppression. To address these challenges, engineered biomaterials have been exploited to enhance DC-mediated immunotherapeutic effects. In this review, vital principal components that can enhance DC-mediated immunotherapeutic effects are first introduced. The parameters considered in the rational design of biomaterials, including targeting modifications, size, shape, surface, and mechanical properties, which can affect biomaterial optimization of DC functions, are further summarized. Moreover, recent applications of various engineered biomaterials in the field of DC-mediated immunotherapy are reviewed, including those serve as immune component delivery platforms, remodel the tumor microenvironment, and synergistically enhance the effects of other antitumor therapies. Overall, the present review comprehensively and systematically summarizes biomaterials related to the promotion of DC functions; and specifically focuses on the recent advances in biomaterial designs for DC activation to eradicate tumors. The challenges and opportunities of treatment strategies designed to amplify DCs via the application of biomaterials are discussed with the aim of inspiring the clinical translation of future DC-mediated cancer immunotherapies.

Using host-guest interactions at the interface of quantum dots to load drug molecules for biocompatible, safe, and effective chemo-photodynamic therapy against cancer

Combining photodynamic therapy (PDT) and chemotherapy (CHT) by loading an anti-cancer drug and a photosensitizer (PS) into the same delivery nanosystem has been proposed as an effective approach to achieve synergistic effects for a safe cancer treatment. However, exploring an ideal delivery nanosystem has been challenging, because the noncovalent interactions must be maintained between the multiple components to produce a stable yet responsive nanostructure that takes into account the encapsulation of drug molecules. We addressed this issue by engineering the interfacial interaction between Ag₂S quantum dots (QDs) using a pillararene derivative to direct the co-self-assembly of the entire system. The high surface area-to-volume ratio of the Ag₂S QDs provided ample hydrophobic space to accommodate the anti-drug molecule doxrubicine. Moreover, Ag₂S QDs served as PSs triggered by 808 nm near-infrared (NIR) light and also as carriers for high-efficiency delivery of drug molecules to the tumor site. Drug release experiments showed smart drug release under the acidic microenvironments (pH 5.5) in tumor cells. Additionally, the Ag₂S QDs demonstrated outstanding PDT ability under NIR light, as confirmed by extracellular and intracellular reactive oxygen species generation. Significant treatment efficacy of the chemo-photodynamic synergistic therapy for cancer using the co-delivery system was demonstrated via in vitro and in vivo studies. These findings suggest that our system offers intelligent control of CHT and PDT, which will provide a promising strategy for constructing hybrid systems with synergistic effects for advanced applications in biomedicine, catalysis, and optoelectronics.

Activating Nanomedicines with Electromagnetic Energy for Deep-Tissue Induction of Immunogenic Cell Death in Cancer Immunotherapy

Immunotherapy is an attractive approach for cancer therapy, while its antitumor efficacy is still limited, especially for non-immunogenic tumors. Nanomedicines can be utilized to convert the non-immunogenic "cold" tumors to immunogenic "hot" tumors via inducing immunogenic cell death (ICD), thereby promoting the antitumor immune response. Some nanomedicines that can produce local heat and reactive oxygen species upon the stimulation of electromagnetic energy are the main candidates for inducing the ICD effect. However, their applications are often restricted due to the poor tissue penetration depths of electromagnetic energy, such as light. By contrast, ultrasound, X-ray, alternating magnetic field, and microwave show excellent tissue penetration depths and thereby can be used for sonodynamic therapy, radiotherapy, magnetic hyperthermia therapy, and microwave ablation therapy, all of which can effectively induce ICD. Herein, the combination of deep-tissue electromagnetic energy with nanomedicines for inducing ICD and cancer immunotherapy are summarized. In particular, the designs of nanomedicines to amplify ICD effect in the presence of deep-tissue electromagnetic energy and sensitize tumors to various immunotherapies will be discussed. At the end of this review, a brief conclusion and discussion of current challenges and further perspectives in this subfield are provided.

Cancer Immunotherapy Elicited by Immunogenic Cell Death Based on Smart Nanomaterials

Cancer immunotherapy has been a revolutionary cancer treatment modality because it can not only eliminate primary tumors but also prevent metastases and recurrent tumors. Immunogenic cell death (ICD) induced by various treatment modalities, including chemotherapy, phototherapy, and radiotherapy, converts dead cancer cells into therapeutic vaccines, eliciting a systemic antigen-specific antitumor. However, the outcome effect of cancer immunotherapy induced by ICD has been limited due to the low accumulation efficiency of ICD inducers in the tumor site and concomitant damage to normal tissues. The boom in smart nanomaterials is conducive to overcoming these hurdles owing to their virtues of good stability, targeted lesion site, high bioavailability, on-demand release, and good biocompatibility. Herein, the design of targeted nanomaterials, various ICD inducers, and the applications of nanomaterials responsive to different stimuli, including pH, enzymes, reactive oxygen species, or dual responses are summarized. Furthermore, the prospect and challenges are briefly outlined to provide reference and inspiration for designing novel smart nanomaterials for immunotherapy induced by ICD.

Multifunctional Nano-Biomaterials for Cancer Therapy via Inducing Enhanced Immunogenic Cell Death

Immunotherapy is considered to be one of the most promising methods to overcome cancer. Immunogenic cell death (ICD), as a special form of cell death that can trigger an antitumor immune response, has attracted increasing attention for cancer immunotherapy. Presently, ICD-mediating immunotherapy needs to overcome many hurdles including a lack of targeted delivery systems for ICD inducers, insufficient antitumor immunity, and the immunosuppressive tumor microenvironment. Recent research has demonstrated that nano-biomaterials exhibit unique biochemphysical properties at the nanoscale, providing a prospective approach to overcoming these obstacles. In this review, the authors first survey the occurrence, processes, and detection methods of ICD. Subsequently, the recent advances of nano-biomaterials applied to enhance ICD according to the key steps in the process of ICD, particularly with a focus on the mechanisms and lifting schemes are investigated. Finally, based on the achievement in the representative studies, the prospects and challenges of nanotechnology in ICD for cancer therapy are discussed to enable clinical translation.

Bimetallic infinite coordination nanopolymers via phototherapy and STING activation for eliciting robust antitumor immunity

Phototherapy can trigger immunogenic cell death of tumors in situ, whereas it is virtually impossible to eradicate the tumor due to the intrinsic resistance and inefficient anti-tumor immunity. To overcome these limitations, novel bimetallic infinite coordination nanopolymers (TA-Fe/Mn-OVA@MB NPs) were synthesized using model antigen ovalbumin (OVA) as a template to assemble tannic acid (TA) and bi-metal, supplemented with methylene blue (MB) surface absorption. The formulated TA-Fe/Mn-OVA@MB NPs possess excellent photothermal and photodynamic therapy (PTT/PDT) performance, which is adequate to destroy tumor cells by physical and chemical attack. Especially, these TA-Fe/Mn-OVA@MB NPs are capability of promoting the dendritic cells (DCs) maturation and antigen presentation via manganese-mediated cGAS-STING pathway activation, finally activating cytotoxicity T lymphocyte and promoting memory T lymphocyte differentiation in the peripheral lymphoid organs. In conclusion, this research offers a versatile metal-polyphenol nanoplatform to integrate functional metals and therapeutic molecule for topical phototherapy and robust anti-tumor immune activation.

A CaCO3-based synergistic immunotherapy strategy for treating primary and distal tumors

Low response rate limits the widespread application of cancer immunotherapy. To improve the response rate of immunotherapy, a CaCO₃-based composite nanomaterial was developed to induce immunogenic cell death for enhancing immunotherapy against 4T1 primary and distal tumors.

Metal-Organic Frameworks Applications in Synergistic Cancer Photo-Immunotherapy

Conventional cancer therapies, such as radiotherapy and chemotherapy, can have long-term side effects. Phototherapy has significant potential as a non-invasive alternative treatment with excellent selectivity. Nevertheless, its applicability is restricted by the availability of effective photosensitizers and photothermal agents, and its low efficacy when it comes to avoiding metastasis and tumor recurrence. Immunotherapy can promote systemic antitumoral immune responses, acting against metastasis and recurrence; however, it lacks the selectivity displayed by phototherapy, sometimes leading to adverse immune events. The use of metal-organic frameworks (MOFs) in the biomedical field has grown significantly in recent years. Due to their distinct properties, including their porous structure, large surface area, and inherent photo-responsive properties, MOFs can be particularly useful in the fields of cancer phototherapy and immunotherapy. MOF nanoplatforms have successfully demonstrated their ability to address several drawbacks associated with cancer phototherapy and immunotherapy, enabling an effective and low-side-effect combinatorial synergistical treatment for cancer. In the coming years, new advancements in MOFs, particularly regarding the development of highly stable multi-function MOF nanocomposites, may revolutionize the field of oncology.

Nanodrug constructed using dietary antioxidants for immunotherapy of metastatic tumors

Immunogenic cell death (ICD) induced by reactive oxygen species (ROS) represents a particular form of tumor cell death for approaching the problem of low immunogenicity of tumors in immunotherapy, while the oxidative damage to normal cells of current ICD inducers hinders their clinical application. Herein, a new ICD inducer VC@cLAV constructed solely by dietary antioxidants, lipoic acid (LA) and vitamin C (VC), is developed, which could promote heavy intracellular ROS production in cancer cells for ICD induction while acting as an anti-oxidant in non-cancer cells for cytoprotection, and thus hold high biosafety. In vitro studies show that VC@cLAV induced a release of antigens and a maturation rate of DCs up to 56.5%, approaching the positive control (58.4%). In vivo combined with αPD-1, VC@cLAV showed excellent antitumor activity against both primary and distant metastatic tumors with an inhibition rate of 84.8% and 79.0% compared to 14.2% and 10.0% in the αPD-1 alone group. Notably, VC@cLAV established a long-term antitumor immune memory effect against tumor rechallenging. This study not only presents a new kind of ICD inducer but also provides an impetus for the development of dietary antioxidant-based cancer drugs.

Titanium-Based Nanoarchitectures for Sonodynamic Therapy-Involved Multimodal Treatments

Sonodynamic therapy (SDT) has considerably revolutionized the healthcare sector as a viable noninvasive therapeutic procedure. It employs a combination of low-intensity ultrasound and chemical entities, known as a sonosensitizer, to produce cytotoxic reactive oxygen species (ROS) for cancer and antimicrobial therapies. With nanotechnology, several unique nanoplatforms are introduced as a sonosensitizers, including, titanium-based nanomaterials, thanks to their high biocompatibility, catalytic efficiency, and customizable physicochemical features. Additionally, developing titanium-based sonosensitizers facilitates the integration of SDT with other treatment modalities (for example, chemotherapy, chemodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy), hence increasing overall therapeutic results. This review summarizes the most recent developments in cancer therapy and tissue engineering using titanium nanoplatforms mediated SDT. The synthesis strategies and biosafety aspects of Titanium-based nanoplatforms for SDT are also discussed. Finally, various challenges and prospects for its further development and potential clinical translation are highlighted.

A nanodrug combining CD47 and sonodynamic therapy efficiently inhibits osteosarcoma deterioration

Treatments for osteosarcoma (OS) with pulmonary metastases reach a bottleneck with a survival rate of 10-20%. The suppressive tumor associated macrophages(TAMs) and CD47 over-expression greatly lead to the treatment failure. Sonodynamic therapy (SDT) can generate ROS with deep tumor penetration to induce tumor cell apoptosis, which is reported to further induce M1 macrophage polarization. CD47 inhibition combined with SDT to synergistically modulate TAMs may induce superior effects for OS treatment. In this work, for the first time, a biomimetic nanodrug named MPIRx was deveploped by loading IR780 (a sonosensitizer) and RRx-001 (a CD47 inhibitor) in PEG-PCL nanomicelles and then coating with OS cell membranes. After ultrasound activation, the nanodrug significantly inhibited OS proliferation and migration, induced apoptosis and immunogenic cell death in OS cells. Furthermore, MPIRx could guide macrophage migrating towards tumor cells and promote M1-type polarization while increasing the phagocytosis activity of macrophages on OS cells. Ultimately, MPIRx showed good tumor accumulation in vivo and successfully inhibited subcutaneous OS and orthotopic tumor with deterioration of pulmonary metastasis. Overall, by creating a local oxidative microenvironment and modulating the TAMs/CD47 in tumor tissue, the MPIRx nanodrug presents a novel strategy for macrophage-related immunotherapy to successfully eliminate OS and inhibit the intractable pulmonary metastasis.

Integrated Nanorod-Mediated PD-L1 Downregulation in Combination with Oxidative-Stress Immunogene Therapy against Cancer

It is an engaging program for tumor treatment that rationalizes the specific microenvironments, activation of suppressed immune system (immune resistance/escape reversion), and synergistic target therapy. Herein, a biomimetic nanoplatform that combines oxidative stress with genetic immunotherapy to strengthen the therapeutic efficacy is developed. Ru-TePt nanorods, small interfering RNA (PD-L1 siRNA), and biomimetic cellular membrane vesicles with the targeting ability to design a multifunctional Ru-TePt@siRNA-MVs system are rationally integrated. Notably, the Fenton-like activity significantly enhances Ru-TePt nanorods sonosensitization, thus provoking stronger oxidative stress to kill cells directly. Meanwhile, immunogenic cell death is triggered to secrete numerous cytokines and activate T cells. The effective catalase characteristics of Ru-TePt enable the in situ oxygen-producing pump to improve tumor oxygen level and coordinately strengthen the therapeutic effect of SDT followed. More importantly, anti-PD-L1-siRNA mediated immune checkpoint silence of the PD-L1 gene creates an environment conducive to activating cytotoxic T lymphocytes, synergistic with boosted reactive oxygen species-triggered antitumor immune response. The experimental results in vitro and in vivo reveal that the Ru-TePt@siRNA-MVs nanosystems can effectively activate the oxidative stress-triggered immune response and inhibit PD-1/PD-L1 axis-mediated immune resistance. Consequently, this orchestrated treatment paradigm provides valuable insights for developing potential oxidative stress and genetic immunotherapy.

A mitochondria-localized iridium(iii) photosensitizer for two-photon photodynamic immunotherapy against melanoma

Conventional photodynamic therapy mainly causes a therapeutic effect on the primary tumor through the localized generation of reactive oxygen species, while metastatic tumors remain poorly affected. Complementary immunotherapy is effective in eliminating small, non-localized tumors distributed across multiple organs. Here, we report the Ir(iii) complex Ir-pbt-Bpa as a highly potent immunogenic cell death inducing photosensitizer for two-photon photodynamic immunotherapy against melanoma. Ir-pbt-Bpa can produce singlet oxygen and superoxide anion radicals upon light irradiation, causing cell death by a combination of ferroptosis and immunogenic cell death. In a mouse model with two physically separated melanoma tumors, although only one of the primary tumors was irradiated, a strong tumor reduction of both tumors was observed. Upon irradiation, Ir-pbt-Bpa not only induced the immune response of CD8⁺ T cells and the depletion of regulatory T cells, but also caused an increase in the number of the effector memory T cells to achieve long-term anti-tumor immunity.

Polymeric nanoparticle-based nanovaccines for cancer immunotherapy

Therapeutic cancer vaccines, which are designed to amplify tumor-specific T cell responses, have been envisioned as one of the most powerful tools for effective cancer immunotherapy. However, increasing the potency, quality and durability of the vaccine response remains a big challenge. In recent years, materials-based delivery systems focusing on the co-delivery of antigens and adjuvants to enhance cancer vaccination therapy have attracted increasing interest. Among various materials, polymeric nanoparticles (NPs) with different physicochemical properties which can incorporate multiple immunological cues are of great interest. In this review, the recent progress in the design and construction of both ex vivo subunit and in situ cancer vaccines using polymeric NPs is summarized. Especially, we will focus on how these NPs improve the adjuvanticity of vaccines. The design principles of polymeric NPs for ex vivo subunit cancer vaccines and in situ cancer vaccination are also discussed. Finally, we want to briefly discuss molecular chaperones in cancer immunity and the applications of our unique self-assembly mixed shell polymeric micelle-based nanochaperones for cancer vaccines.

Identification of Key Biomarkers Associated with Immunogenic Cell Death and Their Regulatory Mechanisms in Severe Acute Pancreatitis Based on WGCNA and Machine Learning

Immunogenic cell death (ICD) is a form of programmed cell death with a strong sense of inflammatory detection, whose powerful situational awareness can cause the reactivation of aberrant immunity. However, the role of ICD in the pathogenesis of severe acute pancreatitis (SAP) has yet to be investigated. This study aims to explore the pivotal genes associated with ICD in SAP and how they relate to immune infiltration and short-chain fatty acids (SCFAs), in order to provide a theoretical foundation for further, in-depth mechanistic studies. We downloaded GSE194331 datasets from the Gene Expression Omnibus (GEO). The use of differentially expressed gene (DEG) analysis; weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression analysis allowed us to identify a total of three ICD-related hub genes (LY96, BCL2, IFNGR1) in SAP. Furthermore, single sample gene set enrichment analysis (ssGSEA) demonstrated that hub genes are closely associated with the infiltration of specific immune cells, the activation of immune pathways and the metabolism of SCFAs (especially butyrate). These findings were validated through the analysis of gene expression patterns in both clinical patients and rat animal models of SAP. In conclusion, the first concept of ICD in the pathogenesis of SAP was proposed in our study. This has important implications for future investigations into the pro-inflammatory immune mechanisms mediated by damage-associated molecular patterns (DAMPs) in the late stages of SAP.

Tumor Cell-Responsive Photodynamic Immunoagent for Immunogenicity-Enhanced Orthotopic and Remote Tumor Therapy

Combining photodynamic therapy (PDT) and immune checkpoint blockades is an efficient method to maximize immunotherapeutic outcome by boosting tumor immunogenicity and modulating the immunosuppressive tumor microenvironment. However, the always-on bioactivity of photosensitizers or immune checkpoint inhibitors leads to uncontrollable side effects, limiting the in vivo therapeutic efficacy of treatments. An activatable strategy is of great importance for improving the selectivity during cancer therapy. In this study, a photodynamic immunomodulator, ICy-NLG, is developed by conjugating the photosensitizer ICy-NH2 with the indoleamine 2,3-dioxygenase 1 inhibitor NLG919 through a glutathione (GSH)-cleavable linker to achieve activatable photodynamic immunotherapy. The conjugation considerably suppresses both the PDT effect and the activity of the inhibitor. After ICy-NLG is activated by high levels of GSH in tumor cells, the PDT effect is restored and leads to immunogenic tumor cell death. The released tumor-associated antigens in conjunction with the activated immune checkpoint inhibitor induce a synergistic antitumor immune response, resulting in the growth inhibition of primary and distant tumors and the prevention of lung metastasis in mouse xenograft models.

Targeted implementation strategies of precise photodynamic therapy based on clinical and technical demands

With the development of materials science, photodynamic-based treatments have gradually entered clinics. Photodynamic therapy is ideal for cancer treatment due to its non-invasive and spatiotemporal properties and is the first to be widely promoted in clinical practice. However, the shortcomings resulting from the gap between technical and clinical demands, such as phototoxicity, low tissue permeability, and tissue hypoxia, limit its wide applications. This article reviews the available data regarding the pharmacological and clinical factors affecting the efficacy of photodynamic therapy, such as photosensitizers and oxygen supply, disease diagnosis, and other aspects of photodynamic therapy. In addition, the synergistic treatment of photodynamic therapy with surgery and nanotechnology is also discussed, which is expected to provide inspiration for the design of photodynamic therapy strategies.

Carrier-Free Nanoplatform via Evoking Pyroptosis and Immune Response against Breast Cancer

Pyroptosis, as a novel mode of cell death, has been proven to have impressive antitumor effects. Dying cells undergoing pyroptosis can elicit antitumor immunity by the release of tumor-associated antigens (TAAs) and damage-associated molecular patterns (DAMPs). Accordingly, developing an effective, stable, and controllable nanoplatform that can promote these two side effects is a promising option for cancer therapy. In this study, we designed a carrier-free chemo-photodynamic nanoplatform (A-C/NPs) using a co-assembly strategy with cytarabine (Ara-C) and chlorin e6 (Ce6) to induce pyroptosis and a subsequent immune response against breast cancer. Mechanistically, A-C/NPs can trigger GSDME-mediated pyroptosis in a controllable manner through reactive oxygen species (ROS) accumulation, causing immunogenic cell death (ICD), in which dying cells release high-mobility group box 1 (HMGB1), adenosine triphosphate (ATP), and calcitonin (CRT). Additionally, Ara-C can stimulate the maturation of cytotoxic T lymphocytes to act synergistically with Ce6-mediated immunogenic cell death (ICD), collectively augmenting the anticancer effect of A-C/NPs. The A-C/NPs showed excellent suppressive effects on the growth of orthotopic, abscopal, and recurrent tumors in a breast cancer mouse model. The chemo-photodynamic therapy (PDT) using the proposed nanomedicine strategy could be a novel strategy for triggering pyroptosis and improving the global anticancer immune response.

Carrier-Free Immunotherapeutic Nano-Booster with Dual Synergistic Effects Based on Glutaminase Inhibition Combined with Photodynamic Therapy

The immunotherapeutic effect elicited by photodynamic therapy (PDT) is attenuated by tumor defense mechanisms associated with glutamine metabolism, including the metabolic regulation of redox homeostasis and the limitation of the immunosuppressive tumor microenvironment (ITM). Herein, a carrier-free immunotherapeutic nanobooster C9SN with dual synergistic effects was constructed by the self-assembly of glutaminase (GLS) inhibitor compound 968 (C968) and photosensitizer Chlorin e6. C968-mediated GSH deprivation through inhibiting glutamine metabolism prevented PDT-generated reactive oxygen species from being annihilated by GSH, amplifying intracellular oxidative stress, which caused severe cell death and also enhanced the immunogenic cell death (ICD) effect. In addition, genome-wide analysis was carried out using RNA-sequencing to evaluate the changes in cell transcriptome induced by amplifying oxidative stress. Thereafter, neoantigens generated by the enhanced ICD effect promoted the maturation of dendritic cells, thereby recruiting and activating cytotoxic T lymphocytes (CTLs). Meanwhile, C9SN remodeled the ITM by blocking glutamine metabolism to polarize M2-type tumor-associated macrophages (TAMs) into M1-type TAMs, which further recruited and activated the CTLs. Ultimately, this immunotherapeutic nanobooster suppressed primary and distant tumors. This "kill two birds with one stone" strategy would shed light on enhancing tumor immunogenicity and alleviating tumor immunosuppression to improve the immunotherapeutic effect of PDT.

Immunomodulatory activity of manganese dioxide nanoparticles: Promising for novel vaccines and immunotherapeutics

Manganese (Mn), a nutrient inorganic trace element, is necessary for a variety of physiological processes of animal body due to their important roles in oxidative regulation effects and other aspects of activities. Moreover, manganese ion (Mn²⁺) has widely reported to be crucial for the regulations of different immunological responses, thus showing promising application as potential adjuvants and immunotherapeutics. Taking the advantages of Mn-based biological and immunological activities, Manganese dioxide nanoparticles (MnO₂ NPs) are a new type of inorganic nanomaterials with numerous advantages, including simple preparation, low cost, environmental friendliness, low toxicity, biodegradable metabolism and high bioavailability. MnO₂ NPs, as a kind of drug carrier, have also shown the ability to catalyze hydrogen peroxide (H₂O₂) to produce oxygen (O₂) under acidic conditions, which can enhance the efficacy of radiotherapy, chemotherapy and other therapeutics for tumor treatment by remodeling the tumor microenvironment. More importantly, MnO₂ NPs also play important roles in immune regulations both in innate and adaptive immunity. In this review, we summarize the biological activities of Manganese, followed by the introduction for the biological and medical functions and mechanisms of MnO₂ NPs. What's more, we emphatically discussed the immunological regulation effects and mechanisms of MnO₂ NPs, as well as their potentials to serve as adjuvants and immunomodulators, which might benefit the development of novel vaccines and immunotherapies for more effective disease control.

Aggregation-Induced-Emission Photosensitizer-Loaded Nano-Superartificial Dendritic Cells with Directly Presenting Tumor Antigens and Reversed Immunosuppression for Photodynamically Boosted Immunotherapy

The success of tumor immunotherapy highlights the potential of harnessing immune system to fight cancer. Activating both native T cells and exhausted T cells is a critical step for generating effective antitumor immunity, which is determined based on the efficient presentation of tumor antigens and co-stimulatory signals by antigen-presenting cells, as well as immunosuppressive reversal. However, strategies for achieving an efficient antigen presentation process and improving the immunosuppressive microenvironment remain unresolved. Here, aggregation-induced-emission (AIE) photosensitizer-loaded nano-superartificial dendritic cells (saDC@Fs-NPs) are developed by coating superartificial dendritic cells membranes from genetically engineered 4T1 tumor cells onto nanoaggregates of AIE photosensitizers. The outer cell membranes of saDC@Fs-NPs are derived from recombinant lentivirus-infected 4T1 tumor cells in which peptide-major histocompatibility complex class I, CD86, and anti-LAG3 antibody are simultaneously anchored. These saDC@Fs-NPs could directly stimulate T-cell activation and reverse T-cell exhaustion for cancer immunotherapy. The inner AIE-active photosensitizers induce immunogenic cell death to activate dendritic cells and enhance T lymphocyte infiltration by photodynamic therapy, promoting the transformation of "cold tumors" into "hot tumors," which further boosts immunotherapy efficiency. This work presents a powerful photoactive and artificial antigen-presenting platform for activating both native T cells and exhausted T cells, as well as facilitating tumor photodynamic immunotherapy.

Biomaterial-assisted tumor therapy: A brief review of hydroxyapatite nanoparticles and its composites used in bone tumors therapy

Malignant bone tumors can inflict significant damage to affected bones, leaving patients to contend with issues like residual tumor cells, bone defects, and bacterial infections post-surgery. However, hydroxyapatite nanoparticles (nHAp), the principal inorganic constituent of natural bone, possess numerous advantages such as high biocompatibility, bone conduction ability, and a large surface area. Moreover, nHAp's nanoscale particle size enables it to impede the growth of various tumor cells via diverse pathways. This article presents a comprehensive review of relevant literature spanning the past 2 decades concerning nHAp and bone tumors. The primary goal is to explore the mechanisms responsible for nHAp's ability to hinder tumor initiation and progression, as well as to investigate the potential of integrating other drugs and components for bone tumor diagnosis and treatment. Lastly, the article discusses future prospects for the development of hydroxyapatite materials as a promising modality for tumor therapy.

Reversing ferroptosis resistance by MOFs through regulation intracellular redox homeostasis

As a non-apoptotic cell death form, ferroptosis offers an alternative approach to overcome cancer chemotherapy resistance. However, accumulating evidence indicates cancer cells can develop ferroptosis resistance by evolving antioxidative defense mechanisms. To address this issue, we prepared a Buthionine-(S,R)-sulfoximine (BSO) loaded metal organic framework (MOF) of BSO-MOF-HA (BMH) with the combination effect of boosting oxidative damage and inhibiting antioxidative defense. MOF nanoparticle was constructed by the photosensitizer of [4,4,4,4-(porphine-5,10,15,20-tetrayl) tetrakis (benzoic acid)] (TCPP) and the metal ion of Zr6, which was further decorated with hyaluronic acid (HA) in order to impart active targeting to CD44 receptors overexpressed cancer cells. BMH exhibited a negative charge and spherical shape with average particle size about 162.5 nm. BMH was found to restore the susceptibility of 4T1 cells to ferroptosis under irradiation. This was attributed to the combination of photodynamic therapy (PDT) and γ-glutamylcysteine synthetase inhibitor of BSO, shifting the redox balance to oxidative stress. Enhanced ferroptosis also induced the release of damage associated molecular patterns (DAMPs) to maturate dendritic cells and activated T lymphocytes, leading to superior anti-tumor performance in vivo. Taken together, our findings demonstrated that boosting oxidative damage with photosensitizer serves as an effective strategy to reverse ferroptosis resistance.

Injectable versatile liquid-solid transformation implants alliance checkpoint blockade for magnetothermal dynamic-immunotherapy

The ongoing circulating energy loss, low reactive oxygen species (ROS) accumulation and poor immunogenicity of tumors make it difficult to induce sufficient immunogenic cell death (ICD) in the tumor immunosuppressive microenvironment (TIME), resulting in unsatisfactory immunotherapy efficacy. Furthermore, for highly malignant tumors, simply enhancing ICD is insufficient for exhaustively eliminating the tumor and inhibiting metastasis. Herein, we propose a unique magnetothermal-dynamic immunotherapy strategy based on liquid-solid transformation porous versatile implants (Fe₃O₄/AIPH@PLGA) that takes advantage of less energy loss and avoids ongoing circulating losses by minimally invasive injection into tumors. In addition, the magnetothermal effect regresses and eliminates tumors that are not limited by penetration to simultaneously trigger 2,2′-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH) decomposition and generate a large amount of oxygen-irrelevant free radicals and heat shock protein (HSP) accumulation by heating, evoking both intracellular oxidative stress and endoplasmic reticulum (ER) stress to induce large-scale ICD and enhance tumor immunogenicity. More importantly, in orthotopic bilateral breast tumor models, a significant therapeutic effect was obtained after combining amplified ICD with CTLA4 checkpoint blockade. The 21-day primary and distant tumor inhibition rates reached 90%, and the underlying mechanism of the effective synergetic strategy of inducing the T-cell-related response, the immune memory effect and TIME reprogramming in vivo was verified by immune cell analyses. This remarkable therapeutic effect provides a new direction for antitumor immunotherapy based on magnetothermally controlled oxygen-independent free radical release.

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Injectable versatile liquid-solid phase transformation Fe₃O₄/AIPH@PLGA gel implants are constructed for the first time.

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The implants triggered magnetothermal dynamic therapy and successfully addressed two key barriers limiting the efficacy of immunogenic cell death (ICD): low reactive oxygen species (ROS) accumulation and poor immunogenicity.

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The implants promoting DC maturation, recognition and presentation of antigens. Combined with CTLA4 blockade, the function of Treg cells was inhibited to transform the “cold” TIME into “hot”.

Molecularly engineering a dual-drug nanoassembly for self-sensitized photodynamic therapy via thioredoxin impairment and glutathione depletion

Photodynamic therapy (PDT) has been extensively investigated as a spatiotemporally noninvasive and controllable modality for cancer treatment. However, the intracellular antioxidant systems mainly consisting of thioredoxin (Trx) and glutathione (GSH) significantly counteract and prevent reactive oxygen species (ROS) accumulation, resulting in a serious loss of PDT efficiency. To address this challenge, we propose that PDT can be improved by precisely blocking antioxidant systems. After molecular engineering and synergistic cytotoxic optimization, a DSPE-PEG_2K-modified dual-drug nanoassembly (PPa@GA/DSPE-PEG_2K NPs) of pyropheophorbide a (PPa) and gambogic acid (GA) is successfully constructed. Interestingly, GA can effectively destroy intracellular antioxidant systems by simultaneously inhibiting Trx and GSH. Under laser irradiation, the cell-killing effects of PPa is significantly enhanced by GA-induced inhibition of the antioxidant systems. As expected, PPa@GA/DSPE-PEG_2K nanoparticles demonstrate potent antitumor activity in a 4T1 breast tumor-bearing BALB/c mouse xenograft model. Such a carrier-free self-sensitized nanotherapeutic offers a novel co-delivery strategy for effective PDT.

Multifunctional Hollow MnO2 @Porphyrin@Bromelain Nanoplatform for Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) has been showing great potential in cancer treatment. However, the efficacy of PDT is always limited by the intrinsic hypoxic tumor microenvironment (TME) and the low accumulation efficiency of photosensitizers in tumors. To address the issue, a multifunctional hollow multilayer nanoplatform (H-MnO₂ @TPyP@Bro) comprising manganese dioxide, porphyrin (TPyP) and bromelain (Bro), is developed for enhanced photodynamic therapy. MnO₂ catalyzes the intracellular hydrogen peroxide (H₂ O₂ ) to produce oxygen (O₂ ), reversing the hypoxic TME in vivo. The generated O₂ is converted into singlet oxygen (¹ O₂ ) by the TPyP shell under near-infrared light, which can inhibit tumor proliferation. Meanwhile, the Bro can digest collagen in the extracellular matrix around the tumor, and can promote the accumulation of H-MnO₂ @TPyP@Bro in the deeper tumor tissue, further improving the therapeutic effect of PDT. In addition, MnO₂ can react with the overexpressed glutathione in TME to release Mn²⁺ . Consequently, Mn²⁺ not only induces chemo-dynamic therapy based on Fenton reaction by converting H₂ O₂ into hydroxyl radicals, but also activates the Mn²⁺ -based magnetic resonance imaging. Therefore, the developed H-MnO₂ @TPyP@Bro nanoplatform can effectively modulate the unfavorable TME and overcome the limitations of conventional PDT for cancer diagnostic and therapeutic.

Combining PD-L1 blockade with immunogenic cell death induced by AIE photosensitizer to improve antitumor immunity

Immunogenic cell death (ICD) is considered an effective death mode to trigger immune response. However, the currently available efficient ICD inducers are quite limited. Endoplasmic reticulum (ER) stress is known as the precursor of ICD, which can be directly triggered by reactive oxygen species in situ. Herein, a novel photosensitizer (α-Th-TPA-PIO) based on phosphindole oxide, featuring aggregation-induced emission (AIE) is designed and prepared, which possesses good ability of hydroxyl radicals (HO^•) generation. Besides, α-Th-TPA-PIO can selectively accumulate in ER and trigger ER stress under white light irradiation, further leading to effective ICD. Combining with anti-programmed death-ligand 1 (anti-PD-L1), the synergistic effect of photodynamic therapy (PDT) and immune checkpoint blockade can achieve a significantly enhanced inhibition effect on the growth of tumors and simultaneously provoke a systemic antitumor immune response. Notably, by adopting this therapeutic strategy to bilateral and metastatic tumor models, the growth of both primary and distant subcutaneous tumors can be successfully suppressed, and metastatic tumor can also be inhibited to some degree. Taken together, this work not only provides a novel ICD photoinducer based on PDT, but also brings about a useful immunomodulatory strategy to realize superior antitumor effect.

Photodynamic Opening of the Blood-Brain Barrier and the Meningeal Lymphatic System: The New Niche in Immunotherapy for Brain Tumors

Photodynamic therapy (PDT) is a promising add-on therapy to the current standard of care for patients with glioblastoma (GBM). The traditional explanation of the anti-cancer PDT effects involves the PDT-induced generation of a singlet oxygen in the GBM cells, which causes tumor cell death and microvasculature collapse. Recently, new vascular mechanisms of PDT associated with opening of the blood-brain barrier (OBBB) and the activation of functions of the meningeal lymphatic vessels have been discovered. In this review, we highlight the emerging trends and future promises of immunotherapy for brain tumors and discuss PDT-OBBB as a new niche and an important informative platform for the development of innovative pharmacological strategies for the modulation of brain tumor immunity and the improvement of immunotherapy for GBM.

Injectable Carbon Dots-Based Hydrogel for Combined Photothermal Therapy and Photodynamic Therapy of Cancer

Hydrogel has been widely used in modern biotherapeutics due to its excellent biocompatibility, degradability, and high drug loading capacity. Among them, the construction of a phototherapy system including photosensitizer and hydrogel has aroused great interest in tumor therapy. Unfortunately, complex modifications are necessary to integrate different photosensitizers into the hydrogel. In this work, an injectable hydrogel was proposed by the Schiff base reaction between HA-CHO and carbon dots (CDs), which can realize PTT and PTT simultaneously. Notably, the CDs with rich -NH2 can be used not only as a photosensitizer but also as an efficient cross-linking agent for the Schiff base reaction to form a hydrogel network. The CD@Hydrogel with outstanding biosafety showed a high antitumor effect after 660 nm laser irradiation in in vitro and in vivo experiments. In summary, the CD@Hydrogel can not only realize PTT and PDT synergistic treatment under one light source but also act as a cross-linking agent to react with HA-CHO to form hydrogel, which is simple and efficient, providing a new strategy for cancer phototherapy.

Constructing Hypoxia-Tolerant and Host Tumor-Enriched Aggregation-Induced Emission Photosensitizer for Suppressing Malignant Tumors Relapse and Metastasis

Photodynamic immunotherapy is a promising treatment strategy that destroys primary tumors and inhibits the metastasis and relapse of distant tumors. As reactive oxygen species are an intermediary for triggering immune responses, photosensitizers (PSs) that can actively target and efficiently trigger oxidative stress are urgently required. Herein, pyrrolo[3,2-b]pyrrole as an electronic donor is introduced in acceptor-donor-acceptor skeleton PSs (TP-IS1 and TP-IS2) with aggregation-induced emission properties and high absorptivity. Meanwhile, pyrrolo[3,2-b]pyrrole derivatives innovatively prove their ability of type I photoreaction, indicating their promising hypoxia-tolerant advantages. Moreover, M1 macrophages depicting an ultrafast delivery through the cell-to-cell tunneling nanotube pathway emerge to construct TP-IS1@M1 by coating the photosensitizer TP-IS1. Under low concentration of TP-IS1@M1, an effective immune response of TP-IS1@M1 is demonstrated by releasing damage-associated molecular patterns, maturating dendritic cells, and vanishing the distant tumor. These findings reveal insights into developing hypoxia-tolerant PSs and an efficient delivery method with unprecedented performance against tumor metastasis.

Lymph node-targeting nanovaccines for cancer immunotherapy

Cancer immunotherapies such as tumor vaccines, chimeric antigen receptor T cells and immune checkpoint blockades, have attracted tremendous attention. Among them, tumor vaccines prime immune response by delivering antigens and adjuvants to the antigen presenting cells (APCs), thus enhancing antitumor immunotherapy. Despite tumor vaccines have made considerable achievements in tumor immunotherapy, it remains challenging to efficiently deliver tumor vaccines to activate the dendritic cells (DCs) in lymph nodes (LNs). Rational design of nanovaccines on the basis of biomedical nanotechnology has emerged as one of the most promising strategies for boosting the outcomes of cancer immunotherapy. In recent years, great efforts have been made in exploiting various nanocarrier-based LNs-targeting tumor nanovaccines. In view of the rapid advances in this field, we here aim to summarize the latest progression in LNs-targeting nanovaccines for cancer immunotherapy, with special attention to various nano-vehicles developed for LNs-targeting delivery of tumor vaccines, including lipid-based nanoparticles, polymeric nanocarriers, inorganic nanocarriers and biomimetic nanosystems. Moreover, the recent trends in nanovaccines-based combination cancer immunotherapy are provided. Finally, the rationality, advantages and challenges of LNs-targeting nanovaccines for clinical translation and application are spotlighted.

Evoking tumor associated macrophages by mitochondria-targeted magnetothermal immunogenic cell death for cancer immunotherapy

Immunogenic cell death (ICD) based on endoplasmic reticulum (ER) stress has been widely studied as the fundamentals of cancer immunotherapy. However, the currently available ICD inducers are still very rare and mostly highly toxic chemotherapeutic drugs. Herein, a novel ICD modality based on mitochondrial heat stress by magnetic hyperthermia treatment (MHT), is proposed for effectively evoking tumor-associated macrophages (TAMs) against cancer cells. A monodisperse and biocompatible nanomedicine by grafting arginyl-glycyl-aspartic acid (RGD) and (3-carboxypropyl)triphenylphosphonium bromide (TPP) onto the surface of superparamagnetic ZnCoFe₂O₄@ZnMnFe₂O₄ nanoparticles (MNPs), named as MNPs-RGD-TPP (MRT), was synthesized for mitochondrial heat stress-induced oxidative damage of tumor cells under the magnetothermal manipulation. Such heat stress-damaged mitochondria can cause the immunogenic death of tumor cells to release damage-associated molecular patterns (DAMPs), including ATP and HSP 70, to M1-polarize TAMs, resulting in the reactivated immunoresponse of macrophages against cancer cells. The effectiveness and robustness of MRT nanomedicine in evoking TAMs-mediated extracellular killing or phagocytosis are verified both in vitro and in vivo. Such a therapeutic approach based on mitochondria-targeted magnetothermal ICD for activating TAMs may be instructive to future anticancer immunotherapy.

Molecularly Self-Engineered Nanoamplifier for Boosting Photodynamic Therapy via Cascade Oxygen Elevation and Lipid ROS Accumulation

Photodynamic therapy (PDT) has been extensively explored as a noninvasive cancer treatment modality. However, the dilemma of tumor hypoxia and short half-life of singlet oxygen (¹O₂) severely restrict the therapeutic efficacy of PDT. Herein, we develop a facile three-in-one PDT nanoamplifier (AA@PPa/Hemin NPs) assembled by pyropheophorbide a (PPa), hemin, and arachidonic acid (AA). Interestingly, AA not only acts as an enabler to facilitate the assembly of PPa and hemin in the construction of ternary hybrid nanoassemblies but also acts as a lipid reactive oxygen species (ROS) amplifier for robust PDT. In tumor cells, hemin plays the role of a catalase-like catalyst that accelerates the production of oxygen (O₂) from hydrogen peroxide (H₂O₂), significantly alleviating tumor hypoxia. Under laser irradiation, vast amounts of ¹O₂ generated by PPa trigger the peroxidation of AA to produce large amounts of cytotoxic lipid ROS, immensely amplifying the efficiency of PDT by promptly eliciting cellular oxidative stress. As expected, AA@PPa/Hemin NPs exert potent antitumor activity in a 4T1 breast-tumor-bearing BALB/c mice xenograft model. Such a cascade nanohybrid amplifier provides a novel codelivery platform for accurate and effective PDT of cancer.

Iodine-Rich Nanoadjuvants for CT Imaging–Guided Photodynamic Immunotherapy of Breast Cancer

Immunotherapy, which stimulates the body’s own immune system to kill cancer cells, has shown great promise in the field of cancer therapy. However, the uncontrolled biodistribution of immunotherapeutic drugs may cause severe side effects. Herein, we report an iodine-rich nanoadjuvant (INA) for photo-immunotherapy. INA is prepared by encapsulating a toll-like receptor 7 agonist (R837) and a photosensitizer (phthalocyanine) into an iodine-rich amphiphilic copolymer PEG-PHEMA-I. By virtue of the enhanced permeation and retention (EPR) effect, INA can effectively accumulate into the tumor site. Under light irradiation, photodynamic therapy (PDT) triggered by INA will induce immunogenic cell death (ICD) in the tumor region to trigger the release of immune-associated cytokines. Such a process may further induce the maturation of dendritic cells which will be accelerated by R837, leading to the proliferation of effector T cells for immunotherapy. The photo-immunotherapy mediated by INA shows good anticancer efficacy both in vitro and in vivo. Meanwhile, INA is also a CT contrast agent owing to its high density of iodine, which can successfully illuminate tumors by CT imaging. Thus, our study develops a light-triggered nanoadjuvant for CT imaging–guided enhanced photo-immunotherapy.

Ferroptosis, necroptosis, and pyroptosis in the occurrence and development of ovarian cancer

Ovarian cancer (OC) is one of the most common malignancies that causes death in women and is a heterogeneous disease with complex molecular and genetic changes. Because of the relatively high recurrence rate of OC, it is crucial to understand the associated mechanisms of drug resistance and to discover potential target for rational targeted therapy. Cell death is a genetically determined process. Active and orderly cell death is prevalent during the development of living organisms and plays a critical role in regulating life homeostasis. Ferroptosis, a novel type of cell death discovered in recent years, is distinct from apoptosis and necrosis and is mainly caused by the imbalance between the production and degradation of intracellular lipid reactive oxygen species triggered by increased iron content. Necroptosis is a regulated non-cysteine protease–dependent programmed cell necrosis, morphologically exhibiting the same features as necrosis and occurring via a unique mechanism of programmed cell death different from the apoptotic signaling pathway. Pyroptosis is a form of programmed cell death that is characterized by the formation of membrane pores and subsequent cell lysis as well as release of pro-inflammatory cell contents mediated by the abscisin family. Studies have shown that ferroptosis, necroptosis, and pyroptosis are involved in the development and progression of a variety of diseases, including tumors. In this review, we summarized the recent advances in ferroptosis, necroptosis, and pyroptosis in the occurrence, development, and therapeutic potential of OC.

Bifunctional scaffolds for tumor therapy and bone regeneration: Synergistic effect and interplay between therapeutic agents and scaffold materials

Bone tumor patients often face the problems with cancer cell residues and bone defects after the operation. Therefore, researchers have developed many bifunctional scaffolds with both tumor treatment and bone repair functions. Therapeutic agents are usually combined with bioactive scaffolds to achieve the "bifunctional". However, the synergistic effect of bifunctional scaffolds on tumor therapy and bone repair, as well as the interplay between therapeutic agents and scaffold materials in bifunctional scaffolds, have not been emphasized and discussed. This review proposes a promising design scheme for bifunctional scaffolds: the synergistic effect and interplay between the therapeutic agents and scaffold materials. This review summarizes the latest research progress in bifunctional scaffolds for therapeutic applications and regeneration. In particular, it summarizes the role of tumor therapeutic agents in bone regeneration and the role of scaffold materials in tumor treatment. Finally, a perspective on the future development of bifunctional scaffolds for tumor therapy and bone regeneration is discussed.

Progress of Nanomaterials in Photodynamic Therapy Against Tumor

Photodynamic therapy (PDT) is an advanced therapeutic strategy with light-triggered, minimally invasive, high spatiotemporal selective and low systemic toxicity properties, which has been widely used in the clinical treatment of many solid tumors in recent years. Any strategies that improve the three elements of PDT (light, oxygen, and photosensitizers) can improve the efficacy of PDT. However, traditional PDT is confronted some challenges of poor solubility of photosensitizers and tumor suppressive microenvironment. To overcome the related obstacles of PDT, various strategies have been investigated in terms of improving photosensitizers (PSs) delivery, penetration of excitation light sources, and hypoxic tumor microenvironment. In addition, compared with a single treatment mode, the synergistic treatment of multiple treatment modalities such as photothermal therapy, chemotherapy, and radiation therapy can improve the efficacy of PDT. This review summarizes recent advances in nanomaterials, including metal nanoparticles, liposomes, hydrogels and polymers, to enhance the efficiency of PDT against malignant tumor.