Near-Infrared-Triggered Photodynamic Therapy with Multitasking Upconversion Nanoparticles in Combination with Checkpoint Blockade for Immunotherapy of Colorectal Cancer

Engineering peptide drug therapeutics through chemical conjugation and implication in clinics

The development of peptide drugs has made tremendous progress in the past few decades because of the advancements in modification chemistry and analytical technologies. The novel-designed peptide drugs have been modified through various biochemical methods with improved diagnostic, therapeutic, and drug-delivery strategies. Researchers found it a helping hand to overcome the inherent limitations of peptides and bring continued advancements in their applications. Furthermore, the emergence of peptide-drug conjugates (PDCs)-utilizes target-oriented peptide moieties as a vehicle for cytotoxic payloads via conjugation with cleavable chemical agents, resulting in the key foundation of the new era of targeted peptide drugs. This review summarizes the various classifications of peptide drugs, suitable chemical modification strategies to improve the ADME (adsorption, distribution, metabolism, and excretion) features of peptide drugs, and recent (2015-early 2024) progress/achievements in peptide-based drug delivery systems as well as their fruitful implication in preclinical and clinical studies. Furthermore, we also summarized the brief description of other types of PDCs, including peptide-MOF conjugates and peptide-UCNP conjugates. The principal aim is to provide scattered and diversified knowledge in one place and to help researchers understand the pinching knots in the science of PDC development and progress toward a bright future of novel peptide drugs.

NADPH Oxidases-Inspired Reactive Oxygen Biocatalysts with Electron-Rich Pt Sites to Potently Amplify Immune Checkpoint Blockade Therapy

Clinical immune checkpoint blockade (ICB)-based immunotherapy of malignant tumors only elicits durable responses in a minority of patients, primarily due to the highly immunosuppressive tumor microenvironment. Although inducing immunogenic cell death (ICD) through reactive oxygen biocatalyst represents an attractive therapeutic strategy to amplify ICB, currently reported biocatalysts encounter insurmountable challenges in achieving high ROS-generating activity to induce potent ICD. Here, inspired by the natural catalytic characteristics of NADPH oxidases, the design of efficient, robust, and electron-rich Pt-based redox centers on the non-stoichiometric W18O49 substrates (Pt─WOx) to serve as bioinspired reactive oxygen biocatalysts to potently activate the ICD, which eventually enhance cancer immune responses and amplifies the ICB-based immunotherapy is reported. These studies demonstrate that the Pt─WOx exhibits rapid electron transfer capability and can promote the formation of electron-rich and low oxophilic Pt redox centers for superior reactive oxygen biocatalysis, which enables the Pt─WOx-based inducers to trigger endoplasmic reticulum stress directly and stimulate immune responses potently for amplifying the anti-PD-L1-based ICB therapy. This bioinspired design provides a straightforward strategy to engineer efficient, robust, and electron-rich reactive oxygen biocatalysts and also opens up a new avenue to create efficient ICD inducers for primary/metastatic tumor treatments.

Multi-Enzyme Nanoparticles as Efficient Pyroptosis and Immunogenic Cell Death Inducers for Cancer Immunotherapy

Immunotherapy represents a widely employed modality in clinical oncology, leveraging the activation of the human immune system to target and eradicate cancer cells and tumor tissues via endogenous immune mechanisms. However, its efficacy remains constrained by inadequate immune responses within "cold" tumor microenvironment (TME). In this study, a multifunctional nanoscale pyroptosis inducer with cascade enzymatic activity (IMZF), comprising superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and glutathione oxidase (GSHOx), is dissociated within the acidic and glutathione-rich TME. The vigorous enzymatic activity not only generates oxygen (O2) to alleviate hypoxia and promote M2 to M1 macrophage polarization but also yields reactive oxygen species (ROS) and depletes glutathione (GSH) within the TME. Functioning as an immunogenic cell death (ICD) activator and pyroptosis inducer, IMZF synergistically triggers dendritic cell maturation and inflammatory lymphocyte infiltration via ICD-associated pyroptosis, thereby reversing immune suppression within the TMEs. Consequently, it exerts inhibitory effects on both primary and distal tumors. This cascade enzymatic platform-based pyroptosis inducer offers an intelligent strategy for effectively overcoming immune suppression within "cold" tumors, thereby providing a promising avenue for advanced immunotherapeutic interventions.

In vivo self-assembled albumin nanoparticle elicit antitumor immunity of PD-1 inhibitor by imaging and clearing tumor-associated macrophages

Eliciting anti-tumor immune responses and improving the tumor microenvironment crucial for boosting the effectiveness of anti-PD-1 immunotherapy. Tumor-associated macrophages (TAMs), the primary types of immune cells infiltrating tumors, play a critical role in the formation of an immunosuppressive microenvironment. In this study, we constructed a novel Evans Blue (EB)-based in vivo self-assembled nanocarrier system, mUNO-EB-ICG-Fc@Alb nanoparticles (designated as MA NPs), for targeted imaging and clearance of M2-TAMs to elicit antitumor immunotherapy of PD-1 inhibitor. In vitro experiments demonstrated the specific fluorescence imaging and killing effect of MA NPs on M2-TAMs. In vivo experiments shown that MA NPs-induced chemodynamic therapy (CDT) successfully reversed the tumor immunosuppressive microenvironment (ITM), promoted intratumoral infiltration of T lymphocytes, and ultimately enhancing the anti-tumor immunotherapy effect of PD-1 inhibitors. This study might provide good inspiration for improving the therapeutic efficacy of cancer immunotherapy.

Light-Triggered PROTAC Nanoassemblies for Photodynamic IDO Proteolysis in Cancer Immunotherapy

While proteolysis-targeting chimeras (PROTACs) hold great potential for persistently reprogramming the immunosuppressive tumor microenvironment via targeted protein degradation, precisely activating them in tumor tissues and preventing uncontrolled proteolysis at off-target sites remain challenging. Herein, a light-triggered PROTAC nanoassembly (LPN) for photodynamic indoleamine 2,3-dioxygenase (IDO) proteolysis is reported. The LPN is derived from the self-assembly of prodrug conjugates, which comprise a PROTAC, cathepsin B-specific cleavable peptide linker, and photosensitizer, without any additional carrier materials. In colon tumor models, intravenously injected LPNs initially silence the activity of PROTACs and accumulate significantly in targeted tumor tissues due to an enhanced permeability and retention effect. Subsequently, the cancer biomarker cathepsin B begins to trigger the release of active PROTACs from the LPNs through enzymatic cleavage of the linkers. Upon light irradiation, tumor cells undergo immunogenic cell death induced by photodynamic therapy to promote the activation of effector T cells, while the continuous IDO degradation of PROTAC simultaneously blocks tryptophan metabolite-regulated regulatory-T-cell-mediated immunosuppression. Such LPN-mediated combinatorial photodynamic IDO proteolysis effectively inhibits tumor growth, metastasis, and recurrence. Collectively, this study presents a promising nanomedicine, designed to synergize PROTACs with other immunotherapeutic modalities, for more effective and safer cancer immunotherapy.

Exploring the role of m7G modification in Cancer: Mechanisms, regulatory proteins, and biomarker potential

The dysregulation of N(7)-methylguanosine (m7G) modification is increasingly recognized as a key factor in the pathogenesis of cancers. Aberrant expression of these regulatory proteins in various cancers, including lung, liver, and bladder cancers, suggests a universal role in tumorigenesis. Studies have established a strong correlation between the expression levels of m7G regulatory proteins, such as Methyltransferase like 1 (METTL1) and WD repeat domain 4 (WDR4), and clinical parameters including tumor stage, grade, and patient prognosis. For example, in hepatocellular carcinoma, high METTL1 expression is associated with advanced tumor stage and poor prognosis. Similarly, WDR4 overexpression in colorectal cancer correlates with increased tumor invasiveness and reduced patient survival. This correlation underscores the potential of these proteins as valuable biomarkers for cancer diagnosis and prognosis. Additionally, m7G modification regulatory proteins influence cancer progression by modulating the expression of target genes involved in critical biological processes, including cell proliferation, apoptosis, migration, and invasion. Their ability to regulate these processes highlights their significance in the intricate network of molecular interactions driving tumor development and metastasis. Given their pivotal role in cancer biology, m7G modification regulatory proteins are emerging as promising therapeutic targets. Targeting these proteins could offer a novel approach to disrupt the malignant behavior of cancer cells and enhance treatment outcomes. Furthermore, their diagnostic and prognostic value could aid in the early detection of cancer and the selection of appropriate therapeutic strategies, ultimately enhancing patient management and survival rates. This review aims to explore the mechanisms of action of RNA m7G modification regulatory proteins in tumors and their potential applications in cancer progression and treatment. By delving into the roles of these regulatory proteins, we intend to provide a theoretical foundation for the development of novel cancer treatment strategies.

Enhanced Osteosarcoma Immunotherapy via CaCO3 Nanoparticles: Remodeling Tumor Acidic and Immune Microenvironment for Photodynamic Therapy

Osteosarcoma (OS) is a "cold" tumor enriched in noninflammatory M2 phenotype tumor-associated macrophages (TAMs), which limits the efficacy of immunotherapy. The acidic tumor microenvironment (TME), generated by factors such as excess hydrogen (H+) ions and high lactate levels, activates immunosuppressive cells, further promoting a suppressive tumor immune microenvironment (TIME). Therefore, a multitarget synergistic combination strategy that neutralizes the acidic TME and reprograms TAMs can be beneficial for OS therapy. Here, a calcium carbonate (CaCO3)/polydopamine (PDA)-based nanosystem (A-NPs@(SHK+Ce6)) is developed. CaCO3 nanoparticles are used to neutralize H+ ions and alleviate the suppressive TIME, and the loaded SHK not only synergizes with photodynamic therapy (PDT) but also inhibits lactate production, further reversing the acidic TME and repolarizing TAMs to consequently lead to enhanced PDT-induced tumor suppression and comprehensive beneficial effects on antitumor immune responses. Importantly, A-NPs@(SHK+Ce6), in combination with programmed cell death protein 1 (PD-1) checkpoint blockade, shows a remarkable ability to eliminate distant tumors and promote long-term immune memory function to protect against rechallenged tumors. This work presents a novel multiple-component combination strategy that coregulates the acidic TME and TAM polarization to reprogram the TIME.

G4-Hemin-loaded 2D nanosheets for combined and targeted chemo-photodynamic cancer therapy

Synergetic combination therapy is emerging as one of the most promising approaches for cancer treatment. Among the various therapeutic approaches, PDT has received particular attention due to its non-invasive nature. However, the therapeutic performance of PDT is severely affected by tumour hypoxia. Herein, we report a supramolecular strategy for the fabrication of a PDT-active 2D nanosheet loaded with a POD mimicking DNAzyme for the synergetic combination of PDT and CDT for targeted cancer therapy. Assembly of biotin-functionalized BODIPY (1) and cationic β-cyclodextrin (β-CD+) leads to the formation of a 1/β-CD+ nanosheet with positively charged β-CD+ on the surface of the sheet. The cationic face of the 1/β-CD+ sheet was then loaded with a POD-mimicking Hem-loaded G-quadruplex aptamer (Hem/DNA1) via electrostatic interactions (1/β-CD+/Hem/DNA1). Cellular internalization of the 1/β-CD+/Hem/DNA1 nanosheet occurs via a receptor-mediated endocytic pathway, which then undergoes lysosomal escape. Subsequently, Hem/DNA1 on the surface of 1/β-CD+/Hem/DNA1 reacts with endogenous H2O2via the Fenton pathway to produce ˙OH and O2. Moreover, under cellular conditions, Hem inside the 1/β-CD+/Hem/DNA1 nanosheet produces Fe2+, which then undergoes another Fenton reaction to produce ˙OH and O2. The Fe3+ generated after the Fenton reaction is then reduced in situ to Fe2+ by glutathione for the next Fenton cycle. At the same time, photoirradiation of the 1/β-CD+ nanosheet using a 635 nm laser produces 1O2via the PDT pathway by using endogenous O2. The most remarkable feature of the present nanoformulation is the cooperativity in its therapeutic action, wherein O2 produced during the CDT pathway was used by the 1/β-CD+ sheet for improving its PDT efficacy in the hypoxic tumor microenvironment. This work represents a unique combination of CDT and PDT for targeted cancer therapy, wherein the CDT action of the nanoagent enhances the PDT efficacy and we strongly believe that this approach would encourage researchers to design similar combination therapy for advancements in the treatment of cancer.

Glutathione-Sensitive Photosensitizer-Drug Conjugates Target the Mitochondria to Overcome Multi-Drug Resistance in Cancer

Multi-drug resistance (MDR) is a major cause of cancer therapy failure. Photodynamic therapy (PDT) is a promising modality that can circumvent MDR and synergize with chemotherapies, based on the generation of reactive oxygen species (ROS) by photosensitizers. However, overproduction of glutathione (GSH) by cancer cells scavenges ROS and restricts the efficacy of PDT. Additionally, side effects on normal tissues are unavoidable after PDT treatment. Here, to develop organic systems that deliver effective anticancer PDT and chemotherapy simultaneously with very little side effects, three GSH-sensitive photosensitizer-drug conjugates (CyR-SS-L) are designed and synthesized. CyR-SS-L localized in the mitochondria then is cleaved into CyR-SG and SG-L parts by reacting with and consuming high levels of intracellular GSH. Notably, CyR-SG generates high levels of ROS in tumor cells instead of normal cells and be exploited for PDT and the SG-L part is used for chemotherapy. CyR-SS-L inhibits better MDR cancer tumor inhibitory activity than indocyanine green, a photosensitizer (PS) used for PDT in clinical applications. The results appear to be the first to show that CyR-SS-L may be used as an alternative PDT agent to be more effective against MDR cancers without obvious damaging normal cells by the combination of PDT, GSH depletion, and chemotherapy.

CaCO3-Encapsulated polydopamine with an adsorbed TLR7 agonist for improved tumor photothermal immunotherapy

Because of the tumor's recurrence and significant metastasis, the standard single-therapy paradigm has failed to meet clinical requirements. Recently, researchers have focused their emphasis on phototherapy and immunogenic cell death (ICD) techniques. In response to the current problems of immunotherapy, a multifunctional drug delivery nanosystem (PDA-IMQ@CaCO3-blinatumomab, PICB) was constructed by using high physiological compatibility of polydopamine (PDA) and calcium carbonate (CaCO3). Toll-like receptor 7 (TLR7) agonist imiquimod (IMQ) and bispecific antibody (BsAb) blinatumomab were loaded onto PDA-CaCO3 nanoparticles (NPs). The findings revealed that the system exhibited the advantages of good dispersion, high stability, excellent physiological compatibility, low toxicity, and high drug loading rate. Compared to the control group, it resulted in a 2.4-fold decrease in FOXP3+ regulatory T-cells within the tumor and a 5.0-fold increase in CD4+ effector T-cells, and promoted the production of damage-related molecular patterns to reinvigorate the ICD effect. PICB had a strong inhibitory effect on tumor growth in 4T1 tumor-bearing mice, and has no toxicity to other organs. Therefore, the multifunctional drug delivery nanosystem constructed in this study could effectively exert the properties of various components in vivo, fully demonstrate the synergistic effect between immunotherapy and photothermal therapy, thus significantly improving the tumor therapeutic efficacy, and has a promising clinical application.

An Electron Donor-Acceptor Structured Rhenium(I) Complex Photo-Sensitizer Evokes Mutually Reinforcing "Closed-Loop" Ferroptosis and Immunotherapy

The hypoxic microenvironment of solid tumors severely lowers the efficacy of oxygen-dependent photodynamic therapy (PDT). The development of hypoxia-tolerant photosensitizers for PDT is an urgent requirement. In this study, a novel rhenium complex (Re-TTPY) to develop a "closed-loop" therapy based on PDT-induced ferroptosis and immune therapy is reported. Due to its electron donor-acceptor (D-A) structure, Re-TTPY undergoes energy transfer and electron transfer processes under 550 nm light irradiation and displays hypoxia-tolerant type I/II combined PDT capability, which can generate 1O2, O2 -, and ·OH simultaneously. Further, the reactive oxygen species (ROSs) leads to the depletion of 1,4-dihydronicotinamide adenine dinucleotide (NADH), glutathione peroxidase 4 (GPX4), and glutathione (GSH). As a result, ferroptosis occurs in cells, simultaneously triggers immunogenic cell death (ICD), and promotes the maturation of dendritic cells (DCs) and infiltration of T cells. The release of interferon-γ (IFN-γ) by CD8+ T cells downregulates the expression of GPX4, further enhancing the occurrence of ferroptosis, and thereby, forming a mutually reinforcing "closed-loop" therapeutic approach.

Sensitize Tumor Immunotherapy: Immunogenic Cell Death Inducing Nanosystems

Low immunogenicity of tumors poses a challenge in the development of effective tumor immunotherapy. However, emerging evidence suggests that certain therapeutic approaches, such as chemotherapy, radiotherapy, and phototherapy, can induce varying degrees of immunogenic cell death (ICD). This ICD phenomenon leads to the release of tumor antigens and the maturation of dendritic cells (DCs), thereby enhancing tumor immunogenicity and promoting immune responses. However, the use of a single conventional ICD inducer often fails to achieve in situ tumor ablation and establish long-term anti-tumor immune responses. Furthermore, the induction of ICD induction varies among different approaches, and the distribution of the therapeutic agent within the body influences the level of ICD and the occurrence of toxic side effects. To address these challenges and further boost tumor immunity, researchers have explored nanosystems as inducers of ICD in combination with tumor immunotherapy. This review examines the mechanisms of ICD and different induction methods, with a specific focus on the relationship between ICD and tumor immunity. The aim is to explore the research advancements utilizing various nanomaterials to enhance the body's anti-tumor effects by inducing ICD. This paper aims to contribute to the development and clinical application of nanomaterial-based ICD inducers in the field of cancer immunotherapy by providing important theoretical guidance and practical references.

ROS-responsive and triple-synergistic mitochondria-targeted polymer micelles for efficient induction of ICD in tumor therapeutics

Immunogenic cell death (ICD) represents a modality of apoptosis distinguished by the emanation of an array of damage-related molecular signals. This mechanism introduces a novel concept in the field of contemporary tumor immunotherapy. The inception of reactive oxygen species (ROS) within tumor cells stands as the essential prerequisite and foundation for ICD induction. The formulation of highly efficacious photodynamic therapy (PDT) nanomedicines for the successful induction of ICD is an area of significant scientific inquiry. In this work, we devised a ROS-responsive and triple-synergistic mitochondria-targeted polymer micelle (CAT/CPT-TPP/PEG-Ce6, CTC) that operates with multistage amplification of ROS to achieve the potent induction of ICD. Utilizing an "all-in-one" strategy, we direct both the PDT and chemotherapeutic units to the mitochondria. Concurrently, a multistage cyclical amplification that caused by triple synergy strategy stimulates continuous, stable, and adequate ROS generation (domino effect) within the mitochondria of cells. Conclusively, influenced by ROS, tumor cell-induced ICD is effectively activated, remodeling immunogenicity, and enhancing the therapeutic impact of PDT when synergized with chemotherapy. Empirical evidence from in vitro study substantiates that CTC micelles can efficiently provoke ICD, catalyzing CRT translocation, the liberation of HMGB1 and ATP. Furthermore, animal trials corroborate that polymer micelles, following tail vein injection, can induce ICD, accumulate effectively within tumor tissues, and markedly inhibit tumor growth subsequent to laser irradiation. Finally, transcriptome analysis was carried out to evaluate the changes in tumor genome induced by CTC micelles. This work demonstrates a novel strategy to improve combination immunotherapy using nanotechnology.

A review of biomolecules conjugated lanthanide up-conversion nanoparticles-based fluorescence probes in food safety and quality monitoring applications

Upconversion nanoparticles (UCNPs) are known to possess unique characteristics, which allow them to overcome a number of issues that plague traditional fluorescence probes. UCNPs have been employed in a variety of applications, but it is arguably in the realm of optical sensors where they have shown the most promise. Biomolecule conjugated UCNPs-based fluorescence probes have been developed to detect and quantify a wide range of analytes, from metal ions to biomolecules, with great specificity and sensitivity. In this review, we have given much emphasis on the recent trends and progress in the preparation strategies of bioconjugated UCNPs and their potential application as fluorescence sensors in the trace level detection of food industry-based toxicants and adulterants. The paper discusses the preparation and functionalisation strategies of commonly used biomolecules over the surface of UCNPs. The use of different sensing strategies namely heterogenous and homogenous assays, underlying fluorescence mechanisms in the detection process of food adulterants are summarized in detail. This review might set a precedent for future multidisciplinary research including the development of novel biomolecules conjugated UCNPs for potential applications in food science and technology.

"Three Musketeers" Enhances Photodynamic Effects by Reducing Tumor Reactive Oxygen Species Resistance

Photodynamic therapy (PDT) based on upconversion nanoparticles (UCNPs) has been widely used in the treatment of a variety of tumors. Compared with other therapeutic methods, this treatment has the advantages of high efficiency, strong penetration, and controllable treatment range. PDT kills tumors by generating a large amount of reactive oxygen species (ROS), which causes oxidative stress in the tumor. However, this killing effect is significantly inhibited by the tumor's own resistance to ROS. This is because tumors can either deplete ROS by high concentration of glutathione (GSH) or stimulate autophagy to eliminate ROS-generated damage. Furthermore, the tumor can also consume ROS through the lactic acid metabolic pathway, ultimately hindering therapeutic progress. To address this conundrum, we developed a UCNP-based nanocomposite for enhanced PDT by reducing tumor ROS resistance. First, Ce6-doped SiO2 encapsulated UCNPs to ensure the efficient energy transfer between UCNPs and Ce6. Then, the biodegradable tetrasulfide bond-bridged mesoporous organosilicon (MON) was coated on the outer layer to load chloroquine (CQ) and α-cyano4-hydroxycinnamic acid (CHCA). Finally, hyaluronic acid was utilized to modify the nanomaterials to realize an active-targeting ability. The obtained final product was abbreviated as UCNPs@MON@CQ/CHCA@HA. Under 980 nm laser irradiation, upconverted red light from UCNPs excited Ce6 to produce a large amount of singlet oxygen (1O2), thus achieving efficient PDT. The loaded CQ and CHCA in MON achieved multichannel enhancement of PDT. Specifically, CQ blocked the autophagy process of tumor cells, and CHCA inhibited the uptake of lactic acid by tumor cells. In addition, the coated MON consumed a high level of intracellular GSH. In this way, these three functions complemented each other, just as the "three musketeers" punctured ROS resistance in tumors from multiple angles, and both in vitro and in vivo experiments had demonstrated the elevated PDT efficacy of nanomaterials.

Nanocarrier-Integrated Microneedles: Divulging the Potential of Novel Frontiers for Fostering the Management of Skin Ailments

The various kinds of nanocarriers (NCs) have been explored for the delivery of therapeutics designed for the management of skin manifestations. The NCs are considered as one of the promising approaches for the skin delivery of therapeutics attributable to sustained release and enhanced skin penetration. Despite the extensive applications of the NCs, the challenges in their delivery via skin barrier (majorly stratum corneum) have persisted. To overcome all the challenges associated with the delivery of NCs, the microneedle (MN) technology has emerged as a beacon of hope. Programmable drug release, being painless, and its minimally invasive nature make it an intriguing strategy to circumvent the multiple challenges associated with the various drug delivery systems. The integration of positive traits of NCs and MNs boosts therapeutic effectiveness by evading stratum corneum, facilitating the delivery of NCs through the skin and enhancing their targeted delivery. This review discusses the barrier function of skin, the importance of MNs, the types of MNs, and the superiority of NC-loaded MNs. We highlighted the applications of NC-integrated MNs for the management of various skin ailments, combinational drug delivery, active targeting, in vivo imaging, and as theranostics. The clinical trials, patent portfolio, and marketed products of drug/NC-integrated MNs are covered. Finally, regulatory hurdles toward benchtop-to-bedside translation, along with promising prospects needed to scale up NC-integrated MN technology, have been deliberated. The current review is anticipated to deliver thoughtful visions to researchers, clinicians, and formulation scientists for the successful development of the MN-technology-based product by carefully optimizing all the formulation variables.

Boosted photo-immunotherapy via near-infrared light excited phototherapy in tumor sites and photo-activation in sentinel lymph nodes

Phototherapy is a promising modality that could eradicate tumor and trigger immune responses via immunogenic cell death (ICD) to enhance anti-tumor immunity. However, due to the lack of deep-tissue-excitable phototherapeutic agents and appropriate excitation strategies, the utility of phototherapy for efficient activation of the immune system is challenging. Herein, we report functionalized ICG nanoparticles (NPs) with the capture capability of tumor-associated antigens (TAAs). Under near-infrared (NIR) light excitation, the ICG NPs exhibited high-performance phototherapy, i.e., synergistic photothermal therapy and photodynamic therapy, thereby efficiently eradicating primary solid tumor and inducing ICD and subsequently releasing TAAs. The ICG NPs also captured TAAs and delivered them to sentinel lymph nodes, and then the sentinel lymph nodes were activated with NIR light to trigger efficient T-cell immune responses through activation of dendritic cells with the assistance of ICG NP generated reactive oxygen species, inhibiting residual primary tumor recurrence and controlling distant tumor growth. The strategy of NIR light excited phototherapy in tumor sites and photo-activation in sentinel lymph nodes provides a powerful platform for active immune systems for anti-tumor photo-immunotherapy.

Enhancing cancer immunotherapy with photodynamic therapy and nanoparticle: making tumor microenvironment hotter to make immunotherapeutic work better

Cancer immunotherapy has made tremendous advancements in treating various malignancies. The biggest hurdle to successful immunotherapy would be the immunosuppressive tumor microenvironment (TME) and low immunogenicity of cancer cells. To make immunotherapy successful, the 'cold' TME must be converted to 'hot' immunostimulatory status to activate residual host immune responses. To this end, the immunosuppressive equilibrium in TME should be broken, and immunogenic cancer cell death ought to be induced to stimulate tumor-killing immune cells appropriately. Photodynamic therapy (PDT) is an efficient way of inducing immunogenic cell death (ICD) of cancer cells and disrupting immune-restrictive tumor tissues. PDT would trigger a chain reaction that would make the TME 'hot' and have ICD-induced tumor antigens presented to immune cells. In principle, the strategic combination of PDT and immunotherapy would synergize to enhance therapeutic outcomes in many intractable tumors. Novel technologies employing nanocarriers were developed to deliver photosensitizers and immunotherapeutic to TME efficiently. New-generation nanomedicines have been developed for PDT immunotherapy in recent years, which will accelerate clinical applications.

Bimetallic nanoparticles as cascade sensitizing amplifiers for low-dose and robust cancer radio-immunotherapy

Radiotherapy (RT) is one of the most feasible and routinely used therapeutic modalities for treating malignant tumors. In particular, immune responses triggered by RT, known as radio-immunotherapy, can partially inhibit the growth of distantly spreading tumors and recurrent tumors. However, the safety and efficacy of radio-immunotherapy is impeded by the radio-resistance and poor immunogenicity of tumor. Herein, we report oxaliplatin (IV)-iron bimetallic nanoparticles (OXA/Fe NPs) as cascade sensitizing amplifiers for low-dose and robust radio-immunotherapy. The OXA/Fe NPs exhibit tumor-specific accumulation and activation of OXA (II) and Fe2+ in response to the reductive and acidic microenvironment within tumor cells. The cascade reactions of the released metallic drugs can sensitize RT by inducing DNA damage, increasing ROS and O2 levels, and amplifying the immunogenic cell death (ICD) effect after RT to facilitate potent immune activation. As a result, OXA/Fe NPs-based low-dose RT triggered a robust immune response and inhibited the distant and metastatic tumors effectively by a strong abscopal effect. Moreover, a long-term immunological memory effect to protect mice from tumor rechallenging is observed. Overall, the bimetallic NPs-based cascade sensitizing amplifier system offers an efficient radio-immunotherapy regimen that addresses the key challenges.

Enhancing photodynamic immunotherapy by reprograming the immunosuppressive tumor microenvironment with hypoxia relief

Tumor hypoxia impairs the generation of reactive oxygen species and the induction of immunogenic cell death (ICD) for photodynamic therapy (PDT), thus impeding its efficacy and the subsequent immunotherapy. In addition, hypoxia plays a critical role in forming immunosuppressive tumor microenvironments (TME) by regulating the infiltration of immunosuppressive tumor-associated macrophages (TAMs) and the expression of programmed death ligand 1 (PD-L1). To simultaneously tackle these issues, a MnO2-containing albumin nanoplatform co-delivering IR780, NLG919, and a paclitaxel (PTX) dimer is designed to boost photodynamic immunotherapy. The MnO2-catalyzed oxygen supply bolsters the efficacy of PDT and PTX-mediated chemotherapy, collectively amplifying the induction of ICD and the expansion of tumor-specific cytotoxic T lymphocytes (CTLs). More importantly, hypoxia releif reshapes the immunosuppressive TME via down-regulating the intratumoral infiltration of M2-type TAMs and the PD-L1 expression of tumor cells to enhance the infiltration and efficacy of CTLs in combination with immune checkpoint blockade (ICB) by NLG919, consequently eradicating primary tumors and almost completely preventing tumor relapse and metastasis. This study sets an example of enhanced immunotherapy for breast cancers through dual ICD induction and simultaneous immunosuppression modulation via both hypoxia relief and ICB, providing a strategy for the treatment of other hypoxic and immunosuppressive cancers.

Recent advances in light-triggered cancer immunotherapy

Light-triggered phototherapies, such as photodynamic therapy (PDT) and photothermal therapy (PTT), have shown strong therapeutic efficacy with minimal invasiveness and systemic toxicity, offering opportunities for tumor-specific therapies. Phototherapies not only induce direct tumor cell killing, but also trigger anti-tumor immune responses by releasing various immune-stimulating factors. In recent years, conventional phototherapies have been combined with cancer immunotherapy as synergistic therapeutic modalities to eradicate cancer by exploiting the innate and adaptive immunity. These combined photoimmunotherapies have demonstrated excellent therapeutic efficacy in preventing tumor recurrence and metastasis compared to phototherapy alone. This review covers recent advancements in combined photoimmunotherapy, including photoimmunotherapy (PIT), PDT-combined immunotherapy, and PTT-combined immunotherapy, along with their underlying anti-tumor immune response mechanisms. In addition, the challenges and future research directions for light-triggered cancer immunotherapy are discussed.

Ultrathin 2D As2Se3 Nanosheets for Photothermal-Triggered Cancer Immunotherapy

Arsenic trioxide (As2O3) has achieved groundbreaking success in the treatment of acute promyelocytic leukemia (APL). However, its toxic side effects seriously limit its therapeutic application in the treatment of solid tumors. To detoxify the severe side effects of arsenic, herein we synthesized innovative 2D ultrathin As2Se3 nanosheets (As2Se3 NSs) with synergistic photothermal-triggered immunotherapy effects. As2Se3 NSs are biocompatible and biodegradable under physiological conditions and can release As(III) and Se(0). Furthermore, selenium increases the immunomodulatory efficacy of arsenic treatments, facilitating reprogramming of the tumor microenvironment by As2Se3 NSs by enhancing the infiltration of natural killer cells and effector tumor-specific CD8+ T cells. The synergistic combination of photothermal therapy and immunotherapy driven by As2Se3 NSs via a simple but effective all-in-one strategy achieved efficient anticancer effects, addressing the key limitations of As2O3 for solid tumor treatment. This work demonstrates not only the great potential of selenium for detoxifying arsenic but also the application of 2D As2Se3 nanosheets for cancer therapy.

Near-Infrared-Responsive Rare Earth Nanoparticles for Optical Imaging and Wireless Phototherapy

Near-infrared (NIR) light is well-suited for the optical imaging and wireless phototherapy of malignant diseases because of its deep tissue penetration, low autofluorescence, weak tissue scattering, and non-invasiveness. Rare earth nanoparticles (RENPs) are promising NIR-responsive materials, owing to their excellent physical and chemical properties. The 4f electron subshell of lanthanides, the main group of rare earth elements, has rich energy-level structures. This facilitates broad-spectrum light-to-light conversion and the conversion of light to other forms of energy, such as thermal and chemical energies. In addition, the abundant loadable and modifiable sites on the surface offer favorable conditions for the functional expansion of RENPs. In this review, the authors systematically discuss the main processes and mechanisms underlying the response of RENPs to NIR light and summarize recent advances in their applications in optical imaging, photothermal therapy, photodynamic therapy, photoimmunotherapy, optogenetics, and light-responsive drug release. Finally, the challenges and opportunities for the application of RENPs in optical imaging and wireless phototherapy under NIR activation are considered.

Macrophage Membrane-Camouflaged Aggregation-Induced Emission Nanoparticles Enhance Photodynamic-Immunotherapy to Delay Postoperative Tumor Recurrence

Surgery is a traditional tumor treatment, and immunotherapy can reduce the postoperative recurrence of tumors. However, the intrinsic limits of low responsive rate and non-tumor specificity of immunotherapy agents are still insufficient to address therapeutic demands. Herein, the macrophages membrane camouflaged nanoparticles (NPs), named M@PFC, consisting of the aggregation-induced emission photosensitizer (PF3-PPh3 ) and immune adjuvant (CpG), are reported. As the protein on the membrane interacts with the vascular cell adhesion molecule 1 (VCAM-1) of cancer cells, M@PFC efficiently transports CpG to the tumor. Meanwhile, M@PFC can evade clearance by the immune system and prolong the circulation time in vivo; thus, enhancing their accumulation in tumors. PF3-PPh3 promotes high production of reactive oxygen species (ROS) and triggers immune cell death (ICD) in tumor cells under light exposure. Importantly, CpG enrichment in tumors can stimulate tumor cells to produce immune factors to assist in enhancing ICD effects. The synergistic effect combining the PDT properties of the aggregation-induced emission (AIE)-active photosensitizer and immunotherapy properties of CpG significantly delays tumor recurrence after surgery. In conclusion, this strategy achieves the synergistic activation of the immune system for anti-tumor activity, providing a novel paradigm for the development of therapeutic nanodrugs to delay postoperative tumor recurrence.

Bibliometric analysis of photodynamic therapy and immune response from 1989-2023

Objective: Photodynamic therapy (PDT) is a minimally invasive treatment approach for precancerous and cancerous lesions, known for its ability to activate the host immune response. This study conducted a bibliometric analysis to identify the research trends and hotspots related to the immune response in PDT. Methods: We analyzed articles and reviews published from 1989 to 2023, retrieved from the Web of Science database. Using Citespace and VOSviewer, we visualized the distribution patterns of these studies in time and space. Results: The analysis revealed a substantial increase in the number of publications on PDT-related immune response since 1989. A total of 1,688 articles from 1,701 institutions were included in this analysis. Among thei nstitutions, the Chinese Academy of Sciences demonstrated exceptional productivity and a willingness to collaborate with others. Additionally, 8,567 authors contributed to the field, with Mladen Korbelik, Michael R. Hamblin, and Wei R. Chen being the most prolific contributors. The current research focus revolves around novel strategies to enhance antitumor immunity in PDT, including PDT-based dendritic cell vaccines, combination therapies with immune checkpoint inhibitors (ICIs), and the use of nanoparticles for photosensitizer delivery. Furthermore, genes such as CD8A, TNF, CD4, IFNG, CD274, IL6, IL10, CALR, HMGB1, and CTLA4 have been evaluated in the context of PDT-related immunity. Conclusion: PDT not only achieves tumor ablation but also stimulates the immune response, bolstering antitumor immunity. This study highlights the emerging hotspots in PDT-related immune response research and provides valuable insights for future investigations aimed at further enhancing antitumor immunity.

Immunotherapy for colorectal cancer: Rational strategies and novel therapeutic progress

There are increasing incidences and mortality rates for colorectal cancer in the world. It is common for chemotherapy and radiation given to patients with colorectal cancer to cause toxicities that limit their effectiveness and cause cancer cells to become resistant to these treatments. Additional targeted treatments are needed to improve patient's quality of life and outcomes. Immunotherapy has rapidly emerged as an incredibly exciting and promising avenue for cancer treatment in recent years. This innovative approach provides novel options for tackling solid tumors, effectively establishing itself as a new cornerstone in cancer treatment. Specifically, in the realm of colorectal cancer (CRC), there is great promise in developing new drugs that target immune checkpoints, offering a hopeful and potentially transformative solution. While immunotherapy of CRC has made significant advances, there are still obstacles and limitations. CRC patients have a poor response to treatment because of the immune-suppressing function of their tumor microenvironment (TME). In addition to blocking inhibitory immune checkpoints, checkpoint-blocking antibodies may also boost immune responses against tumors. The review summarizes recent advances in immune checkpoint inhibitors (ICIs) for CRC, including CTLA-4, PD-1, PD-L1, LAG-3, and TIM-3.

Nanoplatform-enhanced photodynamic therapy for the induction of immunogenic cell death

As an efficient, non-invasive, low-side-effect, and highly selective cancer therapy, photodynamic therapy (PDT) is used to treat various malignant tumors. However, the inefficiency of dealing with deep tumors and metastatic lesions highly limits the use of PDT. Immunogenic cell death (ICD) is a particular form of tumor cell death that could elicit a tumor-special immune response, leading to a systemic anti-tumor effect and providing therapeutic benefits for metastatic lesions. In this regard, it is crucial to enhance the ability of PDT to induce ICD. Luckily, advanced nanotechnology created many promising ways to improve the immunogenicity of PDT and achieve photoimmunotherapy. This review summarizes the emerging strategies for triggering immunogenic cell death via nanoplatform-enhanced PDT, with particular emphasis on their advantages in photoimmunotherapy. We highlight the nanoplatforms classified according to the basic principles of photodynamic therapy and immunogenic cell death, which provides a valuable reference for the design of nanoplatform for photoimmunotherapy. In addition, we also discuss the current situation and prospect of nano-based photoimmunotherapy in clinical studies.

Dynamic immuno-nanomedicines in oncology

Anti-cancer therapeutics have achieved significant advances due to the emergence of immunotherapies that rely on the identification of tumors by the patients' immune system and subsequent tumor eradication. However, tumor cells often escape immunity, leading to poor responsiveness and easy tolerance to immunotherapy. Thus, the potentiated anti-tumor immunity in patients resistant to immunotherapies remains a challenge. Reactive oxygen species-based dynamic nanotherapeutics are not new in the anti-tumor field, but their potential as immunomodulators has only been demonstrated in recent years. Dynamic nanotherapeutics can distinctly enhance anti-tumor immune response, which derives the concept of the dynamic immuno-nanomedicines (DINMs). This review describes the pivotal role of DINMs in cancer immunotherapy and provides an overview of the clinical realities of DINMs. The preclinical development of emerging DINMs is also outlined. Moreover, strategies to synergize the antitumor immunity by DINMs in combination with other immunologic agents are summarized. Last but not least, the challenges and opportunities related to DINMs-mediated immune responses are also discussed.

Bacterial Magnetosome-Hitchhiked Quick-Frozen Neutrophils for Targeted Destruction of Pre-Metastatic Niche and Prevention of Tumor Metastasis

Premetastatic niche (PMN) is a prerequisite for tumor metastasis. Destruction of PMN can significantly suppress the tumor metastasis. Bone marrow-derived cells are usually recruited into the premetastatic organs to support PMN formation, which can be orchestrated by tumor-derived secreted factors. Neutrophils can chemotactically migrate towards the inflammatory sites and consume tumor-derived secreted factors, capable of acting as therapeutic agents for a broad-spectrum suppression of PMN formation and metastasis. However, neutrophils in response to inflammatory signals can release neutrophil extracellular traps (NETs), promoting the tumor metastasis. Herein, live neutrophils are converted into dead neutrophils (C NE) through a quick-frozen process to maintain PMN-targeting and tumor-derived secreted factor-consuming abilities but eliminate NET-releasing shortcomings. Considering macrophages-regulated remodeling of the extracellular matrix in PMN, bacterial magnetosomes (Mag) are further hitchhiked on the surface of C NE to form C NEMag , which can repolarize macrophages from M2 to M1 phenotype for further disruption of PMN formation. A series of in vitro and in vivo assessments have been applied to confirm the effectiveness of C NEMag in suppression of PMN formation and metastasis. This study presents a promising strategy for targeted anti-metastatic therapy in clinics.

Near-Infrared-II Fluorophore with Inverted Dependence of Fluorescence Quantum Yield on Polarity as Potent Phototheranostics for Fluorescence-Image-Guided Phototherapy of Tumors

Organic phototheranostics simultaneously having fluorescence in the second near-infrared (NIR-II, 1000-1700 nm) window, and photothermal and photodynamic functions possess great prospects in tumor diagnosis and therapy. However, such phototheranostics generally suffer from low brightness and poor photodynamic performance due to severe solvatochromism. Herein, an organic NIR-II fluorophore AS1, which possesses an inverted dependence of fluorescence quantum yield on polarity, is reported to serve as potent phototheranostics for tumor diagnosis and therapy. After encapsulation of AS1 into nanostructures, the obtained phototheranostics (AS1R ) exhibit high extinction coefficients (e.g., 68200 L mol-1  cm-1 at 808 nm), NIR-II emission with high fluorescence quantum yield up to 4.7% beyond 1000 nm, photothermal conversion efficiency of ≈65%, and 1 O2 quantum yield up to 4.1%. The characterization of photophysical properties demonstrates that AS1R is superior to other types of organic phototheranostics in brightness, photothermal effect, and photodynamic performance at the same mass concentration. The excellent phototheranostic performance of AS1R enables clear visualization and complete elimination of tumors using a single and low injection dose. This study demonstrates the merits and prospects of NIR-II fluorophore with inverted polarity dependence of fluorescence quantum yield as high-performance phototheranostic agents for fluorescence imaging and phototherapy of tumors.

Drug-drug conjugates self-assembled nanomedicines triggered photo-/immuno- therapy for synergistic cancer treatments

Although immunotherapies have made progress in cancer treatment, their clinical response rates vary widely and are typically low due to sparse immune cell infiltration (immune "cold") and suppressive tumor immune microenvironment (TIME). A simple yet effective approach that integrates a variety of immune-stimulating and TIME-modulating functions could potentially address this clinical challenge. Herein, we conjugate two small molecules, including a photosensitizer (pyropheophorbide-a, PA) and a Toll-like receptor 7/8 agonist (resiquimod, R848), into prodrug (PA-R848) that self-assembles into PA-R848 esterase responsive nanoparticles (PARE NPs) with 100% drug composition and synergistic photo-/immune- therapeutic effects. In PARE NPs, PA exhibits strong phototherapeutic effects which ablate the primary tumor directly and elicits immunogenic cell death (ICD) to promote the immune response. R848 effectively polarizes the M2-type tumor-associated macrophage (TAM) to M1-type TAM, consequently reversing the "cold" and suppressive TIME when working together with phototherapy. The PARE NPs can efficiently pare down the tumor development by two synergisms, including i) synergistic immunotherapy between ICD and TAM polarization; ii) and the antitumor effects between phototherapy and immunotherapy. On a head-neck squamous cell carcinoma mouse model, PARE NPs combined with PD-1 antibody eliminate primary tumors, and significantly inhibit the progress of distant tumors thanks to the robust antitumor immunity enhanced by the PARE NPs.

Photoactivatable base editors for spatiotemporally controlled genome editing in vivo

CRISPR-based base editors (BEs) are powerful tools for precise nucleotide substitution in a wide range of organisms, but spatiotemporal control of base editing remains a daunting challenge. Herein, we develop a photoactivatable base editor (Mag-ABE) for spatiotemporally controlled genome editing in vivo for the first time. The base editing activity of Mag-ABE can be activated by blue light for spatiotemporal regulation of both EGFP reporter gene and various endogenous genes editing. Meanwhile, the Mag-ABE prefers to edit A4 and A5 positions rather than to edit A6 position, showing the potential to decrease bystander editing of traditional adenine base editors. After integration with upconversion nanoparticles as a light transducer, the Mag-ABE is further applied for near-infrared (NIR) light-activated base editing of liver in transgenic reporter mice successfully. This study opens a promising way to improve the operability, safety, and precision of base editing.

Sono-Immunotherapy Mediated Controllable Composite Nano Fluorescent Probes Reprogram the Immune Microenvironment of Hepatocellular Carcinoma

Background

Despite the clinical efficacy of immunotherapy in treating malignant tumors, its effectiveness is often hampered by the immunosuppressive nature of the tumor microenvironment (TME). In this study, we propose the design of a nanoscale ultrasound contrast agent capable of triggering macrophage polarization and immunogenic cell death (ICD) for the treatment of hepatocellular carcinoma (HCC) through sonodynamic treatment (SDT) and immunotherapy.

Methods

The re-educator (designated as ICG@C3F8-R848 NBs) is composed of the Toll-like receptor agonist resiquimod (R848) and the sonosensitizer Indocyanine green (ICG), utilizing nanobubbles (NBs) as carriers. The technique known as ultrasound-targeted nanobubble destruction (UTND) employs nanosized microbubbles and low-frequency ultrasound (LFUS) to ensure accurate drug delivery and enhance safety.

Results

Following intravenous delivery, ICG@C3F8-R848 NBs have the potential to selectively target and treat primary tumors using SDT in conjunction with ultrasonography. Importantly, R848 can enhance antitumor immunity by inducing the polarization of macrophages from an M2 to an M1 phenotype.

Conclusion

The SDT-initiated immunotherapy utilizing ICG@C3F8-R848 NBs demonstrates significant tumor suppression effects with minimal risk of systemic toxicity. The utilization of this self-delivery re-education technique would contribute to advancing the development of nanomedicine for the treatment of hepatocellular carcinoma.

Liposomes for Cancer Theranostics

Cancer is one of the most well-studied diseases and there have been significant advancements over the last few decades in understanding its molecular and cellular mechanisms. Although the current treatments (e.g., chemotherapy, radiotherapy, gene therapy and immunotherapy) have provided complete cancer remission for many patients, cancer still remains one of the most common causes of death in the world. The main reasons for the poor response rates for different cancers include the lack of drug specificity, drug resistance and toxic side effects (i.e., in healthy tissues). For addressing the limitations of conventional cancer treatments, nanotechnology has shown to be an important field for constructing different nanoparticles for destroying cancer cells. Due to their size (i.e., less than 1 μm), nanoparticles can deliver significant amounts of cancer drugs to tumors and are able to carry moieties (e.g., folate, peptides) for targeting specific types of cancer cells (i.e., through receptor-mediated endocytosis). Liposomes, composed of phospholipids and an interior aqueous core, can be used as specialized delivery vehicles as they can load different types of cancer therapy agents (e.g., drugs, photosensitizers, genetic material). In addition, the ability to load imaging agents (e.g., fluorophores, radioisotopes, MRI contrast media) enable these nanoparticles to be used for monitoring the progress of treatment. This review examines a wide variety of different liposomes for cancer theranostics, with the different available treatments (e.g., photothermal, photodynamic) and imaging modalities discussed for different cancers.

Revolutionizing cancer treatment: nanotechnology-enabled photodynamic therapy and immunotherapy with advanced photosensitizers

Nanotechnology-enhanced photodynamic therapy (PDT) and immunotherapy are emerging as exciting cancer therapeutic methods with significant potential for improving patient outcomes. By combining these approaches, synergistic effects have been observed in preclinical studies, resulting in enhanced immune responses to cancer and the capacity to conquer the immunosuppressive tumor microenvironment (TME). Despite challenges such as addressing treatment limitations and developing personalized cancer treatment strategies, the integration of nanotechnology-enabled PDT and immunotherapy, along with advanced photosensitizers (PSs), represents an exciting new avenue in cancer treatment. Continued research, development, and collaboration among researchers, clinicians, and regulatory agencies are crucial for further advancements and the successful implementation of these promising therapies, ultimately benefiting cancer patients worldwide.

Radiotherapy, photodynamic therapy, and cryoablation-induced abscopal effect: Challenges and future prospects

Local therapy modalities such as radiation therapy, photodynamic therapy, photothermal therapy, and cryoablation have been used to treat localized tumors for decades. The discovery of the abscopal effect causes a paradigm shift where local therapy also causes systemic effects and leads to the remission of nonirradiated tumors. The abscopal effect of radiation therapy, alone or in combination with other treatments, has been extensively studied over the last six decades. However, the results are unsatisfactory in producing robust, reproducible, and long-lasting systemic effects. Although immunotherapy and radiation therapy are promising in producing the abscopal effect, the abscopal effect's mechanism is still unclear, owing to various factors such as irradiation type and dose and cancer type. This article reviews the research progress, clinical and preclinical evidence of the abscopal effect by various local therapies alone and in combination with chemotherapy and immunotherapy, case reports, and the current challenges in producing the abscopal effect by various local therapies, focusing on radiotherapy, photodynamic therapy, cryoablation, and the prospects for obtaining a robust, reproducible, and long-lasting abscopal effect.

The dynamic therapeutic effect of a targeted photothermal nanovaccine incorporating toll-like receptor 7 agonist enhanced cancer immunotherapy

Photothermal therapy (PTT) is a noninvasive and effective thermal therapeutic approach. Near-infrared (NIR) light responsive organic nanoparticles (NPs) have been shown to enhance the efficacy of cancer PTT. However, photothermal ablation induced NPs are currently more effective in treating primary and metastatic cancer. Herein, we designed a NIR light responsive theranostic nanosystem that combines PTT with immunotherapy. The caffeic acid doped polyaniline NPs (CA-PANi) were explored for their potential as PTT agents and their ability to mediate immunogenic cell death (ICD). The nano-theranostic agent of CA-PANi functionalized with the RGD (Arg-Gly-Asp) peptide plays a functional role in targeting integrin receptor overexpressed cancer cells. Furthermore, to enhance the immune response in the immune suppressive tumor microenvironment (iTME), imiquimod (R837) a Toll-like receptor 7 agonist that can promote dendritic cell (DC) maturation greatly inhibits tumor growth and tumor recurrence by initiating a strong antitumor immune response. Therefore, combination of PTT and immunotherapy involving CA-PANi-R837-RGD (denoted as CPRR) to improve the therapeutic effect will provide a nanovaccine strategy for targeted antitumor therapy.

Applications of Degradable Hydrogels in Novel Approaches to Disease Treatment and New Modes of Drug Delivery

Hydrogels are particularly suitable materials for loading drug delivery agents; their high water content provides a biocompatible environment for most biomolecules, and their cross-linked nature protects the loaded agents from damage. During delivery, the delivered substance usually needs to be released gradually over time, which can be achieved by degradable cross-linked chains. In recent years, biodegradable hydrogels have become a promising technology in new methods of disease treatment and drug delivery methods due to their many advantageous properties. This review briefly discusses the degradation mechanisms of different types of biodegradable hydrogel systems and introduces the specific applications of degradable hydrogels in several new methods of disease treatment and drug delivery methods.

Nano-immunotherapy: overcoming delivery challenge of immune checkpoint therapy

Immune checkpoint (ICP) molecules expressed on tumor cells can suppress immune responses against tumors. ICP therapy promotes anti-tumor immune responses by targeting inhibitory and stimulatory pathways of immune cells like T cells and dendritic cells (DC). The investigation into the combination therapies through novel immune checkpoint inhibitors (ICIs) has been limited due to immune-related adverse events (irAEs), low response rate, and lack of optimal strategy for combinatorial cancer immunotherapy (IMT). Nanoparticles (NPs) have emerged as powerful tools to promote multidisciplinary cooperation. The feasibility and efficacy of targeted delivery of ICIs using NPs overcome the primary barrier, improve therapeutic efficacy, and provide a rationale for more clinical investigations. Likewise, NPs can conjugate or encapsulate ICIs, including antibodies, RNAs, and small molecule inhibitors. Therefore, combining the drug delivery system (DDS) with ICP therapy could provide a profitable immunotherapeutic strategy for cancer treatment. This article reviews the significant NPs with controlled DDS using current data from clinical and pre-clinical trials on mono- and combination IMT to overcome ICP therapeutic limitations.

A tumor targeted antifouling upconversion nanoplatform for fluorescence imaging and precise photodynamic therapy triggered by NIR laser

Photodynamic therapy (PDT) has been considered as a promising treatment in the biomedical field because of low toxicity to normal tissues and minor trauma area. However, the PDT effect of materials is greatly affected by many factors, such as nonspecific adsorption and poor light penetration, etc. In this work, an intelligent nano platform has been constructed based on upconversion nanoparticles (UCNPs) loaded with a large amount of photosensitizers Ce6, which could specifically light up tumor tissues and stimulate the production of reactive oxygen species (ROS) under 980 nm near-infrared (NIR) irradiation, exhibiting a conspicuous imaging and therapeutic effect of PDT treatment for deep tumors. An excellent anti-fouling performance in complex biological substrate was obtained upon the judicious introduction of anti-fouling peptide, which also contributed to the improved PDT efficiency. In addition, the specificity of nanoplatform to malignant breast cancer cells was realized by modification of polypeptide targeting for HER2. This anti-fouling nanoplatform provided an original paradigm for the development of fluorescence imaging and PDT for deep tumor tissue with high targeting and therapeutic efficacy, promising to be used in the early therapy of malignant breast cancer specifically.

Biomimetic Metal-Chalcogenide Agents Enable Synergistic Cancer Therapy via Microwave Thermal-Dynamic Therapy and Immune Cell Activation

Microwave thermal dynamic therapy (MTDT), which combines thermal effects and reactive oxygen species (ROS) by microwave activation, seems to be a promising anticancer therapeutic method. A multifunctional agent for achieving synergistic localized cancer treatment is the key to exploit the strategy to inhibit tumor cell recurrence and metastasis. In the study, a ZIF-67 based theranostic agent loaded with metal-chalcogenide open framework 3 (MCOF3) and heat shock protein 70 (HSP70) as the inner component was studied, coupled with targeting cancer cell membrane (TCM) as the biomimetic outer shell. We found that metal ions in MCOF3 enabled the composite agents to show peroxide-like activity to produce •OH and destroy cancer cells. And then, the microwave (MW) thermal sensitizer of ZIF-67 was used to specifically convert the MW energy into thermal energy and selectively heat the tumor via the cell's targeting. Additionally, the effect of continuous MW thermal therapy has been shown to promote the expression of HSP70, and further activate the effector of CD4 T cell and CD8α T cell. As such, the agents effectively inhibit the tumor cell growth under MW irradiation in vitro and in vivo due to the synergistic effects of MTDT and immune cell activation. The study provides an emerging strategy to ablation cancer effectively.

Fused Cytomembrane-Camouflaged Nanoparticles for Tumor-Specific Immunotherapy

Tumor immunotherapy is commonly hindered by inefficient delivery and presentation of tumor antigens as well as immunosuppressive tumor microenvironment. To overcome these barriers, a tumor-specific nanovaccine capable of delivering tumor antigens and adjuvants to antigen-presenting cells and modulating the immune microenvironment to elicit strong antitumor immunity is reported. This nanovaccine, named FCM@4RM, is designed by coating the nanocore (FCM) with a bioreconstituted cytomembrane (4RM). The 4RM, which is derived from fused cells of tumorous 4T1 cells and RAW264.7 macrophages, enables effective antigen presentation and stimulation of effector T cells. FCM is self-assembled from Fe(II), unmethylated cytosine-phosphate-guanine oligodeoxynucleotide (CpG), and metformin (MET). CpG, as the stimulator of toll-like receptor 9, induces the production of pro-inflammatory cytokine and the maturation of cytotoxic T lymphocytes (CTLs), thereby enhancing antitumor immunity. Meanwhile, MET functions as the programmed cell death ligand 1 inhibitor and can restore the immune responses of T cells against tumor cells. Therefore, FCM@4RM exhibits high targeting capabilities toward homologous tumors that develop from 4T1 cells. This work offers a paradigm for developing a nanovaccine that systematically regulates multiple immune-related processes to achieve optimal antitumor immunotherapy.

Nanoparticles with transformable physicochemical properties for overcoming biological barriers

In recent years, tremendous progress has been made in the development of nanomedicines for advanced therapeutics, yet their unsatisfactory targeting ability hinders the further application of nanomedicines. Nanomaterials undergo a series of processes, from intravenous injection to precise delivery at target sites. Each process faces different or even contradictory requirements for nanoparticles to pass through biological barriers. To overcome biological barriers, researchers have been developing nanomedicines with transformable physicochemical properties in recent years. Physicochemical transformability enables nanomedicines to responsively switch their physicochemical properties, including size, shape, surface charge, etc., thus enabling them to cross a series of biological barriers and achieve maximum delivery efficiency. In this review, we summarize recent developments in nanomedicines with transformable physicochemical properties. First, the biological dilemmas faced by nanomedicines are analyzed. Furthermore, the design and synthesis of nanomaterials with transformable physicochemical properties in terms of size, charge, and shape are summarized. Other switchable physicochemical parameters such as mobility, roughness and mechanical properties, which have been sought after most recently, are also discussed. Finally, the prospects and challenges for nanomedicines with transformable physicochemical properties are highlighted.

A transformable nanoplatform with multiple therapeutic and immunostimulatory properties for treatment of advanced cancers

Cancer is a complex pathological phenomenon that needs to be treated from different aspects. Herein, we developed a size/charge dually transformable nanoplatform (PDR NP) with multiple therapeutic and immunostimulatory properties to effectively treat advanced cancers. The PDR NPs exhibit three different therapeutic modalities (chemotherapy, phototherapy and immunotherapy) that can be used to effectively treat primary and distant tumors, and reduce recurrent tumors; the immunotherapy is simultaneously activated by three major pathways, including toll-like receptor, stimulator of interferon genes and immunogenic cell death, effectively suppresses the tumor development in combination with an immune checkpoint inhibitor. In addition, PDR NPs show size and charge responsive transformability in the tumor microenvironment, which overcomes various biological barriers and efficiently delivers the payloads into tumor cells. Taking these unique characteristics together, PDR NPs effectively ablate primary tumors, activate strong anti-tumor immunity to suppress distant tumors and reduce tumor recurrence in bladder tumor-bearing mice. Our versatile nanoplatform shows great potential for multimodal treatments against metastatic cancers.

In Situ Tumor Vaccine for Lymph Nodes Delivery and Cancer Therapy Based on Small Size Nanoadjuvant

Tumor vaccine is a promising cancer treatment modality, however, the convenient antigens loading in vivo and efficient delivery of vaccines to lymph nodes (LNs) still remain a formidable challenge. Herein, an in situ nanovaccine strategy targeting LNs to induce powerful antitumor immune responses by converting the primary tumor into whole-cell antigens and then delivering these antigens and nanoadjuvants simultaneously to LNs is proposed. The in situ nanovaccine is based on a hydrogel system, which loaded with doxorubicin (DOX) and nanoadjuvant CpG-P-ss-M. The gel system exhibits ROS-responsive release of DOX and CpG-P-ss-M, generating abundant in situ storage of whole-cell tumor antigens. CpG-P-ss-M adsorbs tumor antigens through the positive surface charge and achieves charge reversal, forming small-sized and negatively charged tumor vaccines in situ, which are then primed to LNs. Eventually, the tumor vaccine promotes antigens uptake by dendritic cells (DCs), maturation of DCs, and proliferation of T cells. Moreover, the vaccine combined with anti-CTLA4 antibody and losartan inhibits tumor growth by 50%, significantly increasing the percentage of splenic cytotoxic T cells (CTLs), and generating tumor-specific immune responses. Overall, the treatment effectively inhibits primary tumor growth and induces tumor-specific immune response. This study provides a scalable strategy for in situ tumor vaccination.

Photodynamic Therapy for Colorectal Cancer: An Update and a Look to the Future

This review provides an update on the current state of photodynamic therapy (PDT) for colorectal cancer (CRC) and explores potential future directions in this field. PDT has emerged as a promising minimally invasive treatment modality that utilizes photosensitizers and specific light wavelengths to induce cell death in targeted tumor tissues. In recent years, significant progress has been made in understanding the underlying mechanisms, optimizing treatment protocols, and improving the efficacy of PDT for CRC. This article highlights key advancements in PDT techniques, including novel photosensitizers, light sources, and delivery methods. Furthermore, it discusses ongoing research efforts and potential future directions, such as combination therapies and nanotechnology-based approaches. By elucidating the current landscape and providing insights into future directions, this review aims to guide researchers and clinicians in harnessing the full potential of PDT for the effective management of CRC.

Understanding the Photodynamic Therapy Induced Bystander and Abscopal Effects: A Review

Photodynamic therapy (PDT) is a clinically approved minimally/non-invasive treatment modality that has been used to treat various conditions, including cancer. The bystander and abscopal effects are two well-documented significant reactions involved in imparting long-term systemic effects in the field of radiobiology. The PDT-induced generation of reactive oxygen and nitrogen species and immune responses is majorly involved in eliciting the bystander and abscopal effects. However, the results in this regard are unsatisfactory and unpredictable due to several poorly elucidated underlying mechanisms and other factors such as the type of cancer being treated, the irradiation dose applied, the treatment regimen employed, and many others. Therefore, in this review, we attempted to summarize the current knowledge regarding the non-targeted effects of PDT. The review is based on research published in the Web of Science, PubMed, Wiley Online Library, and Google Scholar databases up to June 2023. We have highlighted the current challenges and prospects in relation to obtaining clinically relevant robust, reproducible, and long-lasting antitumor effects, which may offer a clinically viable treatment against tumor recurrence and metastasis. The effectiveness of both targeted and untargeted PDT responses and their outcomes in clinics could be improved with more research in this area.

Endogenous/Exogenous Nanovaccines Synergistically Enhance Dendritic Cell-Mediated Tumor Immunotherapy

Traditional dendritic cell (DC)-mediated immunotherapy is usually suppressed by weak immunogenicity in tumors and generally leads to unsatisfactory outcomes. Synergistic exogenous/endogenous immunogenic activation can provide an alternative strategy for evoking a robust immune response by promoting DC activation. Herein, Ti3 C2 MXene-based nanoplatforms (termed MXP) are prepared with high-efficiency near-infrared photothermal conversion and immunocompetent loading capacity to form endogenous/exogenous nanovaccines. Specifically, the immunogenic cell death of tumor cells induced by the photothermal effects of the MXP can generate endogenous danger signals and antigens release to boost vaccination for DC maturation and antigen cross-presentation. In addition, MXP can deliver model antigen ovalbumin (OVA) and agonists (CpG-ODN) as an exogenous nanovaccine (MXP@OC), which further enhances DC activation. Importantly, the synergistic strategy of photothermal therapy and DC-mediated immunotherapy by MXP significantly eradicates tumors and enhances adaptive immunity. Hence, the present work provides a two-pronged strategy for improving immunogenicity and killing tumor cells to achieve a favorable outcome in tumor patients.

Cancer Nanomedicine: Emerging Strategies and Therapeutic Potentials

Cancer continues to pose a severe threat to global health, making pursuing effective treatments more critical than ever. Traditional therapies, although pivotal in managing cancer, encounter considerable challenges, including drug resistance, poor drug solubility, and difficulties targeting tumors, specifically limiting their overall efficacy. Nanomedicine's application in cancer therapy signals a new epoch, distinguished by the improvement of the specificity, efficacy, and tolerability of cancer treatments. This review explores the mechanisms and advantages of nanoparticle-mediated drug delivery, highlighting passive and active targeting strategies. Furthermore, it explores the transformative potential of nanomedicine in tumor therapeutics, delving into its applications across various treatment modalities, including surgery, chemotherapy, immunotherapy, radiotherapy, photodynamic and photothermal therapy, gene therapy, as well as tumor diagnosis and imaging. Meanwhile, the outlook of nanomedicine in tumor therapeutics is discussed, emphasizing the need for addressing toxicity concerns, improving drug delivery strategies, enhancing carrier stability and controlled release, simplifying nano-design, and exploring novel manufacturing technologies. Overall, integrating nanomedicine in cancer treatment holds immense potential for revolutionizing cancer therapeutics and improving patient outcomes.

High-efficiency upconversion process in cobalt and neodymium doped graphene QDs for biomedical applications

Multiphoton absorbing upconversion nanoparticles are emerging as bioimaging materials but are limited by the low quantum yield of their visible fluorescence. This article contains colloids of graphene quantum dots (GQDs), Neodymium, and Cobalt doped Graphene Quantum dots (Co-GQDs and Nd-GQDs) surrounded by carboxylic acids are synthesized which especially are suitable for bio applications; in this way, carboxylic acid groups exchanged by Amoxicillin as an antibiotic with bactericidal activity. The XRD diffraction method, TEM microscope, UV-Vis, and photoluminescence spectroscopies characterize the synthesized materials. The synthesized Quantum dots (QDs) exhibit upconversion properties and their emission is centered at 480 nm, but a red shift was observed with the increase of the excitation wavelength. In the emission spectra of synthesized QDs that can be related to the defect levels introduced by passivation of the QDs in the structure, the results show that with the interaction of the surface QDs with more carboxylic groups, the redshift is not observed. As the results indicate an increase in the intensity of upconversion emission is recorded for Co-GQDs and Nd-GQDs. The absolute quantum efficiency (QY) for Co-GQDs and Nd-GQDs were determined to be 41% and 100% more than GQDs respectively. DFT calculations indicate a strong bond between graphene and cobalt and Neodymium atoms. In doped materials, there are trap levels between the band gap of the GQDs which are responsible for increasing the intensity of the upconversion phenomenon.