A NO/ROS/RNS cascaded-releasing nano-platform for gas/PDT/PTT/immunotherapy of tumors

Advances in herbal polysaccharides-based nano-drug delivery systems for cancer immunotherapy

The boom in cancer immunotherapy has provided many patients with a better chance of survival, but opportunities often come with challenges. Single immunotherapy is not good enough to eradicate tumours, and often fails to achieve the desired therapeutic effect because of the low targeting of immunotherapy drugs, and causes more side effects. As a solution to this problem, researchers have developed several nano Drug Delivery Systems (NDDS) to deliver immunotherapeutic agents to achieve good therapeutic outcomes. However, traditional drug delivery systems (DDS) have disadvantages such as poor bioavailability, high cytotoxicity, and difficulty in synthesis, etc. Herbal Polysaccharides (HPS), derived from natural Chinese herbs, inherently possess low toxicity. Furthermore, the biocompatibility, biodegradability, hydrophilicity, ease of modification, and immunomodulatory activities of HPS offer unique advantages in substituting traditional DDS. This review initially addresses the current developments and challenges in immunotherapy. Subsequently, it focuses on the immunomodulatory mechanisms of HPS and their design as nanomedicines for targeted drug delivery in tumour immunotherapy. Our findings reveal that HPS-based nanomedicines exhibit significant potential in enhancing the efficacy of cancer immunotherapy, providing crucial theoretical foundations and practical guidelines for future clinical applications.

Hybrid nano-stimulator for specific amplification of oxidative stress and precise tumour treatment

BACKGROUND

The use of reactive oxygen species (ROS) to target cancer cells has become a hot topic in tumor therapy.

PURPOSE

Although ROS has strong cytotoxicity against tumor cells, the key issue currently is how to generate a large amount of ROS within tumor cells.

METHODS

Organic/inorganic hybrid nanoreactor materials combine the advantages of organic and inorganic components and can amplify cancer treatment by increasing targeting and material self-action. The multifunctional organic / inorganic hybrid nanoreactor is helpful to overcome the shortcomings of current reactive oxygen species in cancer treatment. It can realize the combination of in situ dynamic therapy and immunotherapy strategies, and has a synergistic anti-tumor effect.

RESULTS

This paper reviews the research progress of organic/inorganic hybrid nanoreactor materials using tumor components to amplify reactive oxygen species for cancer treatment. The article reviews the tumor treatment strategies of nanohybrids from the perspectives of cancer cells, immune cells, tumor microenvironment, as well as 3D printing and electrospinning techniques, which are different from traditional nanomaterial technologies, and will arouse interest among scientists in tumor therapy and nanomedicine.

A dual responsive nitric oxide / β-lapachone co-delivery platform for redox imbalance-enhanced tumor therapy

Nitric oxide (NO) / β-Lapachone (Lap) combined therapy by causing oxidative stress is an effective tumor therapy strategy. Herein, a dual-responsive lipid nanoparticles (LNPs) LSNO for NO / Lap co-delivery were constructed from the zinc-coordinated lipid (DSNO(Zn)) and the hydrophobic drug Lap in the presence of helper lipids (DOPE and DSPE-PEG2000). The zinc-coordinated structure in LSNO might elevate the Zn2+ content in tumor cells, contributing to antioxidant imbalance. The fluorescent assays proved the light-triggered NO release and fluorescent self-reporting abilities of LSNO. In addition, the LNPs had good drug release behavior under high concentration of GSH, indicating the NO / drug co-delivery capacity. In vitro antitumor assays showed that the NO / Lap combination treatment group could induce more significant tumor cell growth inhibition and cell apoptosis than individual NO or Lap treatment. The following mechanism studies revealed that NO / Lap combination treatment led to distinct oxidative stress by producing reactive oxygen species (ROS) and peroxynitrite anion (ONOO-). On the other hand, the intracellular redox balance could be further disrupted by Lap-induced NADPH consumption and Zn2+ / NO-induced reductase activities downregulation, thus promoting the degree of cell damage. Besides, it was also found that NO and Lap could directly damage nuclear DNA and induce mitochondrial dysfunction, thereby leading to caspase-3 activation and tumor cell death. These results proved that LSNO could serve as a promising multifunctional tumor therapy platform.

Photodynamic therapy for cancer: mechanisms, photosensitizers, nanocarriers, and clinical studies

Photodynamic therapy (PDT) is a temporally and spatially precisely controllable, noninvasive, and potentially highly efficient method of phototherapy. The three components of PDT primarily include photosensitizers, oxygen, and light. PDT employs specific wavelengths of light to active photosensitizers at the tumor site, generating reactive oxygen species that are fatal to tumor cells. Nevertheless, traditional photosensitizers have disadvantages such as poor water solubility, severe oxygen-dependency, and low targetability, and the light is difficult to penetrate the deep tumor tissue, which remains the toughest task in the application of PDT in the clinic. Here, we systematically summarize the development and the molecular mechanisms of photosensitizers, and the challenges of PDT in tumor management, highlighting the advantages of nanocarriers-based PDT against cancer. The development of third generation photosensitizers has opened up new horizons in PDT, and the cooperation between nanocarriers and PDT has attained satisfactory achievements. Finally, the clinical studies of PDT are discussed. Overall, we present an overview and our perspective of PDT in the field of tumor management, and we believe this work will provide a new insight into tumor-based PDT.

Advances in porphyrins and chlorins associated with polysaccharides and polysaccharides-based materials for biomedical and pharmaceutical applications

Over the last decade, the convergence of advanced materials and innovative applications has fostered notable scientific progress within the biomedical and pharmaceutical fields. Porphyrins and their derivatives, distinguished by an extended conjugated π-electron system, have a relevant role in propelling these advancements, especially in drug delivery systems, photodynamic therapy, wound healing, and (bio)sensing. However, despite their promise, the practical clinical application of these macrocycles is hindered by their inherent challenges of low solubility and instability under physiological conditions. To address this limitation, researchers have exploited the synergistic association of porphyrins and chlorins with polysaccharides by engineering conjugated systems and composite/hybrid materials. This review compiles the principal advances in this growing research field, elucidating fundamental principles and critically examining the applications of such materials within biomedical and pharmaceutical contexts. Additionally, the review addresses the eventual challenges and outlines future perspectives for this poignant research field. It is expected that this review will serve as a comprehensive guide for students and researchers dedicated to exploring state-of-the-art materials for contemporary medicine and pharmaceutical applications.

Oxygen-Evolving Radiotherapy-Radiodynamic Therapy Synergized with NO Gas Therapy by Cerium-Based Rare-Earth Metal-Porphyrin Framework

The efficacy of traditional radiotherapy (RT) has been severely limited by its significant side effects, as well as tumor hypoxia. Here, the nanoscale cerium (Ce)-based metaloxo clusters (Ce(IV)6)-porphyrin (meso-tetra (4-carboxyphenyl) porphyrin, TCPP) framework loaded with L-arginine (LA) (denoted as LA@Ce(IV)6-TCPP) is developed to serve as a multifarious radio enhancer to heighten X-ray absorption and energy transfer accompanied by O2/NO generation for hypoxia-improved RT-radiodynamic therapy (RDT) and gas therapy. Within tumor cells, LA@Ce(IV)6-TCPP will first react with endogenous H2O2 and inducible NO synthase (iNOS) to produce O2 and NO to respectively increase the oxygen supply and reduce oxygen consumption, thus alleviating tumor hypoxia. Then upon X-ray irradiation, LA@Ce(IV)6-TCPP can significantly enhance hydroxyl radical (•OH) generation from Ce(IV)6 metaloxo clusters for RT and synchronously facilitate singlet oxygen (1O2) generation from adjacently-coordinated TCPP for RDT. Moreover, both the •OH and 1O2 can further react with NO to generate more toxic peroxynitrite anions (ONOO-) to inhibit tumor growth for gas therapy. Benefitting from the alleviation of tumor hypoxia and intensified RT-RDT synergized with gas therapy, LA@Ce(IV)6-TCPP elicited superior anticancer outcomes. This work provides an effective RT strategy by using low doses of X-rays to intensify tumor suppression yet reduce systemic toxicity.

In Situ Photoactivated Antibacterial and Antioxidant Composite Materials to Promote Bone Repair

Trauma and tumor removal usually cause bone defects; in addition, the related postoperative infection also shall be carefully considered clinically. In this study, polylactic acid (PLLA) composite fibers containing Cerium oxide (CeO2) are first prepared by electrospinning technology. Then, the PLLA/CeO2@PDA/Ag composite materials are successfully prepared by reducing silver ion (Ag+) to nano-silver (AgNPs)  coating in situ and binding AgNPs to the materials surface by mussel structure liked polydopamine (PDA). In the materials, Ag+ can be slowly released in simulated body fluids. Based on the photothermal performance of AgNPs, the photothermal conversion efficiency of the materials is 21%, under NIR 808 nm illumination. The effective photothermal conversion can help materials fighting with E. coli and S. aureus in 3 h, with an antibacterial rate of 100%. Additionally, the sustained Ag+ release contributes to the antibacterial in long term. Meanwhile, the materials can mimic the bio-behavior of superoxide dismutase and catalase in decreasing the singlet oxygen level and removing the excess reactive oxygen species. Furthermore, the materials are beneficial for cell proliferation and osteogenic differentiation in vitro. In this study, a promising bone-regenerated material with high photothermal conversion efficiency and antibacterial and anti-oxidation properties, is successfully constructed.

Gastric acid-responsive deformable sodium alginate/Bletilla striata polysaccharide in situ gel for the protection and treatment of alcohol-induced peptic ulcers

First-line drugs for peptic ulcer (PU) treatment are typically limited by poor targeting and adverse effects associated with long-term use. Despite recent advancements in novel therapeutic approaches for PU, the development of sustained-release delivery systems tailored to specific pathological characteristics remains challenging. Persistent inflammation, particularly gastric inflammatory microenvironment imbalance, characterizes the PU. In this study, we prepared an in situ gel composed of sodium alginate, deacetylated gellan gum, calcium citrate, and Bletilla striata polysaccharide (BSP) to achieve sustained release of BSP. The BSP in situ gel demonstrated favorable fluidity in vitro and completed self-assembly in vivo in response to the acidic milieu at a pH of 1.5. Furthermore, the shear, extrusion, and deformation properties increased by 26.4 %, 103.7 %, and 46.3 %, respectively, with long-term gastric retention (4 h) and mucosal adaptation. Animal experiments confirmed that the BSP in situ gel could attenuate necrotic injury and inflammatory cell infiltration, maintain mucosal barrier integrity, regulate cytokine imbalance and inflammation-associated hyperapoptosis, thus effectively alleviate the inflammatory microenvironmental imbalance in PU without significant side effects. Overall, our findings demonstrated that the BSP in situ gel is a promising therapeutic strategy for PU and opens avenues for developing self-assembled formulations targeting the pathological features of PUs.

Dual properties of pharmacological activities and preparation excipient: Bletilla striata polysaccharides

Bletilla striata has been used for thousands of years and shows the functions of stopping bleeding, reducing swelling, and promoting healing in traditional applications. For Bletilla striata, Bletilla striata polysaccharides (BSP) is the main active ingredient, exhibiting biological functions of anti-inflammatory, anti-oxidant, anti-fibrotic, immune modulation, anti-glycation, and so on. In addition, BSP has exhibited the characteristics of excipient such as bio-adhesion, bio-degradability, and bio-safety and has been prepared into a series of preparations such as nanoparticles, microspheres, microneedles, hydrogels, etc. BSP, as both a drug and an excipient, has already aroused more and more attention. In this review, publications in recent years related to the extraction and identification, biological activities, and excipient application of BSP are reviewed. Specifically, we focused on the advances in the application of BSP as a formulation excipient. We hold opinion that BSP not only needed more researches in the mechanisms, but also the development into hydrogels, nano-formulations, tissue engineering, and so on. And we believe that this paper provides a beneficial reference for further BSP innovation and in-depth research and promotes the use of these natural products in pharmaceutical applications.

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.

Carboxylated graphene quantum dots-mediated photothermal therapy enhances drug-membrane permeability, ROS production, and the immune system recruitment on 3D glioblastoma models

Graphene quantum dots (GQDs) are biocompatible nanoparticles employed in biomedical field, thanks to their size and photophysical properties. GQDs have shown the capability to cross biological barriers, including the blood–brain barrier, which makes them promising agents for brain diseases therapy. It has been shown that surface-functionalized GQDs enhance membrane fluidity and intracellular uptake, exerting a synergistic effect with antitumor drugs at subtherapeutic doses. Here, we tested GQDs effects in combination with chemotherapeutic agents doxorubicin and temozolomide, on a complex 3D spheroid model of glioblastoma. We observed that the capability of GQDs to absorb and convert near-infrared light into heat is a key factor in membrane permeability enhancement on 3D model. This non-invasive therapeutic strategy named photothermal therapy (PTT), combined to chemotherapy at subtherapeutic doses, significantly increased the effect of antitumor drugs by reducing tumor growth and viability. Furthermore, the increase in membrane permeability due to GQDs-mediated PTT enhanced the release of reactive oxygen species with strong migration of the immune system towards irradiated cancer spheroids. Our data indicate that the increase in membrane permeability can enhance the efficacy of antitumor drugs at subtherapeutic doses against glioblastoma, reducing side effects, and directing immune response, ultimately improving quality of life for patients.

Polysaccharide-based tumor microenvironment-responsive drug delivery systems for cancer therapy

The biochemical indicators of tumor microenvironment (TME) that are different from normal tissues provide the possibility for constructing intelligent drug delivery systems (DDSs). Polysaccharides with good biocompatibility, biodegradability, and unique biological properties are ideal materials for constructing DDSs. Nanogels, micelles, organic-inorganic nanocomposites, hydrogels, and microneedles (MNs) are common polysaccharide-based DDSs. Polysaccharide-based DDSs enable precise control of drug delivery and release processes by incorporating TME-specific biochemical indicators. The classification and design strategies of polysaccharide-based TME-responsive DDSs are comprehensively reviewed. The advantages and challenges of current polysaccharide-based DDSs are summarized and the future directions of development are foreseen. The polysaccharide-based TME-responsive DDSs are expected to provide new strategies and solutions for cancer therapy and make important contributions to the realization of precision medicine.

Nitrogen-phosphorous co-doped carbonized chitosan nanoparticles for chemotherapy and ROS-mediated immunotherapy of intracellular Staphylococcus aureus infection

Staphylococcus aureus (S. aureus) residing in host macrophages is hard to clear because intracellular S. aureus has evolved mechanisms to hijack and subvert the immune response to favor intracellular infection. To overcome this challenge, nitrogen-phosphorous co-doped carbonized chitosan nanoparticles (NPCNs), which possess the polymer/carbon hybrid structures, were fabricated to clear intracellular S. aureus infection through chemotherapy and immunotherapy. Multi-heteroatom NPCNs were fabricated through the hydrothermal method, where chitosan and imidazole were used as the C and N sources and phosphoric acid as the P source. NPCNs can not only be used as a fluorescent probe for bacteria imaging but also kill extracellular and intracellular bacteria with low cytotoxicity. NPCNs could generate ROS and polarize macrophages into classically activated (M1) phenotypes to increase antibacterial immunity. Furthermore, NPCNs could accelerate intracellular S. aureus-infected wound healing in vivo. We envision that these carbonized chitosan nanoparticles may provide a new platform for clearing intracellular bacterial infection through chemotherapy and ROS-mediated immunotherapy.

Gas-assisted phototherapy for cancer treatment

Phototherapies, mainly including photodynamic and photothermal therapy, have made considerable strides in the field of cancer treatment. With the aid of phototherapeutic agents, reactive oxygen species (ROS) or heat are generated under light irradiation to selectively damage cancer cells. However, sole-modality phototherapy faces certain drawbacks, such as limited penetration of phototherapeutic agents into tumor tissues, inefficient ROS generation due to hypoxia, treatment-induced inflammation and resistance of tumor to treatment (e.g., high levels of antioxidants, expression of heat shock protein). Gas therapy, an emerging therapy approach that damages cancer cells by improving the level of certain gas at the tumor site, shows potential to overcome the challenges associated with phototherapies. In addition, with the rapid development of nanotechnology, gas-assisted phototherapy based on nanomedicines has emerged as a promising strategy to enhance the treatment efficacy. This review summarizes recent advances in gas-assisted phototherapy and discusses the prospects and challenges of this strategy in cancer phototherapy.

Polysaccharide-Based Stimulus-Responsive Nanomedicines for Combination Cancer Immunotherapy

Cancer immunotherapy is a promising antitumor approach, whereas nontherapeutic side effects, tumor microenvironment (TME) intricacy, and low tumor immunogenicity limit its therapeutic efficacy. In recent years, combination immunotherapy with other therapies has been proven to considerably increase antitumor efficacy. However, achieving codelivery of the drugs to the tumor site remains a major challenge. Stimulus-responsive nanodelivery systems show controlled drug delivery and precise drug release. Polysaccharides, a family of potential biomaterials, are widely used in the development of stimulus-responsive nanomedicines due to their unique physicochemical properties, biocompatibility, and modifiability. Here, the antitumor activity of polysaccharides and several combined immunotherapy strategies (e.g., immunotherapy combined with chemotherapy, photodynamic therapy, or photothermal therapy) are summarized. More importantly, the recent progress of polysaccharide-based stimulus-responsive nanomedicines for combination cancer immunotherapy is discussed, with the focus on construction of nanomedicine, targeted delivery, drug release, and enhanced antitumor effects. Finally, the limitations and application prospects of this new field are discussed.

Advanced Nitric Oxide Generating Nanomedicine for Therapeutic Applications

Nitric oxide (NO), a gaseous transmitter extensively present in the human body, regulates vascular relaxation, immune response, inflammation, neurotransmission, and other crucial functions. Nitrite donors have been used clinically to treat angina, heart failure, pulmonary hypertension, and erectile dysfunction. Based on NO's vast biological functions, it further can treat tumors, bacteria/biofilms and other infections, wound healing, eye diseases, and osteoporosis. However, delivering NO is challenging due to uncontrolled blood circulation release and a half-life of under five seconds. With advanced biotechnology and the development of nanomedicine, NO donors packaged with multifunctional nanocarriers by physically embedding or chemically conjugating have been reported to show improved therapeutic efficacy and reduced side effects. Herein, we review and discuss recent applications of NO nanomedicines, their therapeutic mechanisms, and the challenges of NO nanomedicines for future scientific studies and clinical applications. As NO enables the inhibition of the replication of DNA and RNA in infectious microbes, including COVID-19 coronaviruses and malaria parasites, we highlight the potential of NO nanomedicines for antipandemic efforts. This review aims to provide deep insights and practical hints into design strategies and applications of NO nanomedicines.

Three-dimension chitosan hydrogel loading melanin composite nanoparticles for wound healing by anti-bacteria, immune activation and macrophage autophagy promotion

Application of Combined photodynamic therapy (PDT) and photothermal therapy (PTT) has become one of the most promising strategy to replace antibiotics and avoid the epidemic of drug-resistant strains during wound healing. However, high amount of reactive oxygen species (ROS) and high temperature cause severe stress response to normal tissues, leading to potential risks of wound healing. Herein, a three-dimension chitosan hydrogel melanin-glycine-C60 nanoparticles (MGC NPs) were prepared to realized effective anti-bacterial activity, immune activation and macrophage autophagy promotion in three-dimensional wound space without triggering stress response. MGC NP is a composite polymer material composed of natural melanin polymer, oligopeptide and carbon-based material, which showed excellent biological safety. By regulating the peptide length between melanin and C60 and nanoparticle content, a high ROS/heat environment at the upper wound site and a low ROS/heat environment at the lower region adjacent to the wound tissue were established to obtain a three-dimension hydrogel with precise PDT and PTT efficiency in different regions. Highly effective PDT/PTT was used to kill microorganisms in upper region, thus providing a barrier to reduce microbial infection. Mild PDT/PTT in lower region promoted the polarization of M1 macrophage to M2 macrophage and activated autophagy of M2 macrophages, regulating the immune microenvironment and promoting wound repair. In conclusion, the novel three-dimensional PDT/PTT therapy based on natural macromolecules proposed in this study accelerates wound healing through dual pathways on the premise of avoiding wound stress response, which is of great significance for the development of clinical strategies for phototherapy.

Reactive oxygen species-upregulating nanomedicines towards enhanced cancer therapy

Reactive oxygen species (ROS) play a crucial role in physiological and pathological processes, emerging as a therapeutic target in cancer. Owing to the high concentration of ROS in solid tumor tissues, ROS-based treatments, such as photodynamic therapy and chemodynamic therapy, and ROS-responsive drug delivery systems have been widely explored to powerfully and specifically suppress tumors. However, their anticancer efficacy is still hampered by the heterogeneous ROS levels, and thus comprehensively upregulating the ROS levels in tumor tissues can ensure an enhanced therapeutic effect, which can further sensitize and/or synergize with other therapies to inhibit tumor growth and metastasis. Herein, we review the recently emerging drug delivery strategies and technologies for increasing the H₂O₂, ˙OH, ¹O₂, and ˙O₂^- concentrations in cancer cells, including the efficient delivery of natural enzymes, nanozymes, small molecular biological molecules, and nanoscale Fenton-reagents and semiconductors and neutralization of intracellular antioxidant substances and localized input of mechanical and electromagnetic waves (such as ultrasound, near infrared light, microwaves, and X-rays). The applications of these ROS-upregulating nanosystems in enhancing and synergizing cancer therapies including chemotherapy, chemodynamic therapy, phototherapy, and immunotherapy are surveyed. In addition, we discuss the challenges of ROS-upregulating systems and the prospects for future studies.

Fluorescent Self-Reporting Lipid Nanoparticles for Nitric Oxide/Gene Co-Delivery and Combination Therapy

The combination cancer therapy of nitric oxide (NO) with gene therapy is a promising method for tumor treatment. However, efficient co-delivery of gas and therapeutic genes to tumor cells remains a challenge. Herein, we designed a nano-sized ultraviolet (UV) light-responsive cationic lipid vector DPNO(Zn). Fluorescence spectroscopy and confocal imaging experiments revealed that DPNO(Zn) lipid nanoparticles (LNPs) could rapidly release NO under low-power UV light irradiation. Moreover, the fluorescence turn-on might take place along with the release of NO, indicating the self-reporting ability. Gene delivery experiments showed that DPNO(Zn) LNPs had good gene transfection ability, making such materials a good candidate for gas/gene combination therapy. In vitro antitumor assay demonstrated that the co-delivery system was more effective in inhibiting tumor cell proliferation than individual NO or pTrail treatment. Studies on the mechanism of tumor cell apoptosis induced by NO/pTrail co-delivery showed that NO could not only effectively increase the accumulation of p53 protein in tumor cells, thereby promoting the activation of caspase-3, but also induce mitochondrial damage. On the other hand, the Trail protein expressed by pTrail gene could enhance the degree of NO-induced caspase-3 activation, indicating the synergistic effect. These results proved that DPNO(Zn) LNP may serve as a multifunctional nanocarrier for potential tumor therapy.

PpIX/IR-820 Dual-Modal Therapeutic Agents for Enhanced PDT/PTT Synergistic Therapy in Cervical Cancer

High treatment accuracy is the key to efficient cancer treatment. Photodynamic therapy (PDT) and photothermal therapy (PTT) are two kinds of popular, precise treatment methods. The combination of photodynamic and photothermal therapy (PDT/PTT) can greatly enhance the precise therapeutic efficacy. In this work, protoporphyrin IX (PpIX) was selected as the PDT agent (photosensitizer), and new indocyanine green (IR-820) was selected as the PTT agent. Further, the two kinds of theranostic agents were encapsulated by biological-membrane-compatible liposomes to form PpIX-IR-820@Lipo nanoparticles (NPs), a new kind of PDT/PTT agent. The PpIX-IR-820@Lipo NPs exhibited good water solubility, a spherical shape, and high fluorescence peak emission in the near-infrared spectral region (700-900 nm, NIR). The cellular toxicity of PpIX-IR-820@Lipo NPs for human cervical cancer cells (HeLa) and human cervical epithelial cells (H8) was detected by the CCK-8 method, and low cytotoxicity was observed for the PpIX-IR-820@Lipo NPs. Then, the excellent cellular uptake of PpIX-IR-820@Lipo NPs was confirmed by laser scanning confocal microscopy. Moreover, the PDT/PTT property of PpIX-IR-820@Lipo NPs was illustrated via 2',7'-dichlorofluorescin diacetate (DCFH-DA) and annexin V-fluorescein isothiocyanate (annexin V-FITC), as indicator probes. The PDT/PTT synergistic efficiency of PpIX-IR-820@Lipo NPs on HeLa cells was verified, exhibiting a high efficiency of 70.5%. Thus, the novel theranostic PpIX-IR-820@Lipo NPs can be used as a promising PDT/PTT synergistic theranostic nanoplatform in future cervical cancer treatment.

Supramolecular Coassembled Peptide Hydrogels for Efficient Anticancer Therapy by RNS-Based PDT and Immune Microenvironment Regulation

Photodynamic therapy (PDT) has attracted much attention in cancer treatment due to its tumor selectivity and noninvasive nature. Recent studies have demonstrated that PDT mediated reactive oxygen species (ROS) generation in tumor microenvironment (TME) synergistically improves the efficacy of immune checkpoint blockade (ICB) therapy. However, the instability and short half-life of the ROS generated by PDT limit its clinical applications. Herein, a coassembled peptide hydrogel comprising two short peptides that contained the same assembly unit, Ce6-KKFKFEFEF (KEF-Ce6) and RRRRRRRR-KFKFEFEF (KEF-R8) is developed. When exposed to 635 nm laser irradiation, KEF-Ce6 released ROS, while KEF-R8 plays as nitric oxide (NO) donor. Subsequently, ROS reacts with NO to produce reactive nitrogen species (RNS). Both in vitro and in vivo experiments prove that converting ROS into more cytotoxic RNS caused intense cell death. Importantly, it is observed that tumor-associated macrophages (TAMs) are polarized to proinflammatory types (M1-type) by the RNS-based PDT. The increase of M1 macrophages relieves the immunosuppressive situation in TME. Thus, when combined with αPD-L1 treatment, the survival time of tumor-bearing mice is prolonged. Overall, a simple yet efficient coassembled hydrogel that can cascade release ROS/NO/RNS and strengthen antitumor T cell responses to boost cancer immunotherapy by reprogramming TAMs is provided.

Water-Soluble Salts Based on Benzofuroxan Derivatives-Synthesis and Biological Activity

A series of novel water-soluble salts of benzofuroxans was achieved via aromatic nucleophilic substitution reaction of 4,6-dichloro-5-nitrobenzofuroxan with various amines. The salts obtained showed good effectiveness of the pre-sowing treatment of seeds of agricultural crops at concentrations of 20-40 mmol. In some cases, the seed treatment with salts leads not only to improved seed germination, but also to the suppression of microflora growth. Additionally, their anti-cancer activityin vitrohas been researched. The compounds with morpholine fragments or a fragment of N-dimethylpropylamine, demonstrated the highest cytotoxic activity, which is in good correlation with the ability to inhibit the glycolysis process in tumor cells. Two compounds 4e and 4g were selected for further experiments using laboratory animals. It was found that the lethal dose of 50% (LD₅₀) is 22.0 ± 1.33 mg/kg for 4e and 13.75 ± 1.73 mg/kg for 4g, i.e., compound 4e is two times less toxic than 4g, according to the mouse model in vivo. It was shown that the studied compounds exhibit antileukemia activity after a single intraperitoneal injection at doses from 1.25 to 5 mg/kg, as a result of which the average lifespan of animals with a P388 murine leukemia tumor increases from 20 to 28%. Thus, the water-soluble salts of benzofuroxans can be considered as promisingcandidates for further development, both as anti-cancer agents and as stimulants for seed germination and regulators of microflora crop growth.

Nanomaterials-mediated photodynamic therapy and its applications in treating oral diseases

Oral diseases, such as dental caries, periodontitis and oral cancer, have a very high morbidity over the world. Basically, many oral diseases are commonly related to bacterial infections or cell malignant proliferation, and usually located on the superficial positions. These features allow the convenient and efficient application of photodynamic therapy (PDT) for oral diseases, since PDT is ideally suitable for the diseases on superficial sites and has been widely used for antimicrobial and anticancer therapy. Photosensitizers (PSs) are an essential element in PDT, which induce the generation of a large number of reactive oxygen species (ROS) upon absorption of specific lights. Almost all the PSs are small molecules and commonly suffered from various problems in the PDT environment, such as low solubility and poor stability. Recently, reports on the nanomedicine-based PDT have been well documented. Various functionalized nanomaterials can serve either as the PSs carriers or the direct PSs, thus enhancing the PDT efficacy. Herein, we aim to provide a comprehensive understanding of the features of different oral diseases and discuss the potential applications of nanomedicine-based PDT in the treatment of some common oral diseases. Also, the concerns and possible solutions for nanomaterials-mediated PDT are discussed.

Melanin-like nanoparticles: advances in surface modification and tumour photothermal therapy

Currently, tumor treatments are characterized by intelligence, diversity and personalization, but the therapeutic reagents used are often limited in clinical efficacy due to problems with water solubility, targeting, stability and multidrug resistance. To remedy these shortcomings, the application of multifunctional nanotechnology in the biomedical field has been widely studied. Synthetic melanin nanoparticles (MNPs) surfaces which contain highly reactive chemical groups such as carboxyl, hydroxyl and amine groups, can be used as a reaction platform on which to graft different functional components. In addition, MNPs easily adhere to substrate surface, and serve as a secondary reaction platform to modify it. The multifunctionality and intrinsic biocompatibility make melanin-like nanoparticles promising as a multifunctional and powerful nanoplatform for oncological applications. This paper first reviews the preparation methods, polymerization mechanisms and physicochemical properties of melanin including natural melanin and chemically synthesized melanin to guide scholars in MNP-based design. Then, recent advances in MNPs especially synthetic polydopamine (PDA) melanin for various medical oncological applications are systematically and thoroughly described, mainly focusing on bioimaging, photothermal therapy (PTT), and drug delivery for tumor therapy. Finally, based on the investigated literature, the current challenges and future directions for clinical translation are reasonably discussed, focusing on the innovative design of MNPs and further elucidation of pharmacokinetics. This paper is a timely and comprehensive and detailed study of the progress of MNPs in tumor therapy, especially PTT, and provides ideas for the design of personalized and customizable oncology nanomedicines to address the heterogeneity of the tumor microenvironment.

Bacteria-based nanodrug for anticancer therapy

Bacteria-based immunotherapy has become a promising strategy to induce innate and adaptive responses for fighting cancer. The advantages of bacteriolytic tumor therapy mainly lie in stimulation of innate immunity and colonization of some bacteria targeting the tumor microenvironment (TME). These bacteria have cytotoxic proteins and immune modulating factors that can effectively restrain tumor growth. However, cancer is a multifactorial disease and single therapy is typically unable to eradicate tumors. Rapid progress has been made in combining bacteria with nanotechnology. Using the nanomolecular properties of bacterial products for tumor treatment preserves many features from the original bacteria while providing some unique advantages. Nano-bacterial therapy can enhance permeability and retention of drugs, increase the tolerability of the targeted drugs, promote the release of immune cell mediators, and induce immunogenic cell death pathways. In addition, combining nano-bacterial mediated antitumor therapeutic systems with modern therapy is an effective strategy for overcoming existing barriers in antitumor treatment and can achieve satisfactory therapeutic efficacy. Overall, exploring the immune antitumor characteristics of adjuvant clinical treatment with bacteria can provide potential efficacious treatment strategies for combatting cancer.

Tumor-Selective Biodegradation-Regulated Photothermal H2 S Donor for Redox Dyshomeostasis- and Glycolysis Disorder-Enhanced Theranostics

H₂ S-mediated tumor therapy has received great attention due to its unique physiological activity and synergistical enhancement, but suffers from limited H₂ S donors with promised biosafety to regulate the H₂ S delivery and subsequently the elusive pathway to augment the combined therapy. Herein, a PEGylated porous molybdenum disulfide nanoflower (MSP) with abundant defects is facilely synthesized for tumor-targeted theranostics. MSP possesses good water-dispersity and high photothermal ability, which is used for photoacoustic imaging and photothermal therapy. Interestingly, MSP is selectively degraded upon exposure to superfluous glutathione (GSH) within tumor cells, the mechanism of which is investigated, as a reduction-coordination reaction. This special degradation induces redox dyshomeostasis via GSH depletion for reactive oxygen species-accumulated chemodynamic therapy. Meanwhile, the selective biodegradation of MSP regulates a sustained H₂ S release within tumor and achieves a targeted H₂ S gas therapy via enhancing the glycolysis to acidify the tumor cells (glycolysis disorder). Synergistically, these performances are further enhanced via near-infrared photothermal heating, where excellent therapeutic outcomes with good biosafety are accomplished in vitro and in vivo. These characteristics, together with the unique biodegradation and no obvious side-effects of the nanoparticles, suggest a potential therapeutic strategy for precise tumor treatments.

NIR light‐triggered peroxynitrite anion production via direct lanthanide‐triplet photosensitization for enhanced photodynamic therapy

Peroxynitrite anion (ONOO−), a product derived from reaction between reactive oxygen species (ROS) and nitric oxide (NO), is considered to be a more toxic reactive specie than most ROS for...