Biomimetic Metal-Organic Framework Nanoparticles for Cooperative Combination of Antiangiogenesis and Photodynamic Therapy for Enhanced Efficacy

Manganese-derived biomaterials for tumor diagnosis and therapy

Manganese (Mn) is widely recognized owing to its low cost, non-toxic nature, and versatile oxidation states, leading to the emergence of various Mn-based nanomaterials with applications across diverse fields, particularly in tumor diagnosis and therapy. Systematic reviews specifically addressing the tumor diagnosis and therapy aspects of Mn-derived biomaterials are lacking. This review comprehensively explores the physicochemical characteristics and synthesis methods of Mn-derived biomaterials, emphasizing their role in tumor diagnostics, including magnetic resonance imaging, photoacoustic and photothermal imaging, ultrasound imaging, multimodal imaging, and biodetection. Moreover, the advantages of Mn-based materials in tumor treatment applications are discussed, including drug delivery, tumor microenvironment regulation, synergistic photothermal, photodynamic, and chemodynamic therapies, tumor immunotherapy, and imaging-guided therapy. The review concludes by providing insights into the current landscape and future directions for Mn-driven advancements in the field, serving as a comprehensive resource for researchers and clinicians.

Prepared MW-Immunosensitizers Precisely Release NO to Downregulate HIF-1α Expression and Enhance Immunogenic Cell Death

Microwave thermotherapy (MWTT) has limited its application in the clinic due to its high rate of metastasis and recurrence after treatment. Nitric oxide (NO) is a gaseous molecule that can address the high metastasis and recurrence rates after MWTT by increasing thermal sensitivity, down-regulating the expression of hypoxia-inducible factor-1 (HIF-1), and inducing the immunogenic cell death (ICD). Therefore, GaMOF-Arg is designed, a gallium-based organic skeleton material derivative loaded with L-arginine (L-Arg), and coupled the mitochondria-targeting drug of triphenylphosphine (TPP) on its surface to obtain GaMOF-Arg-TPP (GAT) MW-immunosensitizers. When GAT MW-immunosensitizers are introduced into mice through the tail vein, reactive oxygen species (ROS) are generated and L-Arg is released under MW action. Then, L-Arg reacts with ROS to generate NO, which not only downregulates HIF-1 expression to improve tumor hypoxia exacerbated by MW, but also enhances immune responses by augment calreticulin (CRT) exposure, high mobility group box 1 (HMGB1) release, and T-cell proliferation to achieve prevention of tumor metastasis and recurrence. In addition, NO can induce mitochondria damage to increase their sensitivity to MWTT. This study provides a unique insight into the use of metal-organic framework MW-immunosensitizers to enhance tumor therapy and offers a new way to treat cancer efficiently.

Nanomedicine Targeting Myeloid-Derived Suppressor Cells Enhances Anti-Tumor Immunity

Cancer immunotherapy, a field within immunology that aims to enhance the host's anti-cancer immune response, frequently encounters challenges associated with suboptimal response rates. The presence of myeloid-derived suppressor cells (MDSCs), crucial constituents of the tumor microenvironment (TME), exacerbates this issue by fostering immunosuppression and impeding T cell differentiation and maturation. Consequently, targeting MDSCs has emerged as crucial for immunotherapy aimed at enhancing anti-tumor responses. The development of nanomedicines specifically designed to target MDSCs aims to improve the effectiveness of immunotherapy by transforming immunosuppressive tumors into ones more responsive to immune intervention. This review provides a detailed overview of MDSCs in the TME and current strategies targeting these cells. Also the benefits of nanoparticle-assisted drug delivery systems, including design flexibility, efficient drug loading, and protection against enzymatic degradation, are highlighted. It summarizes advances in nanomedicine targeting MDSCs, covering enhanced treatment efficacy, safety, and modulation of the TME, laying the groundwork for more potent cancer immunotherapy.

Nanomaterials-Induced Redox Imbalance: Challenged and Opportunities for Nanomaterials in Cancer Therapy

Cancer cells typically display redox imbalance compared with normal cells due to increased metabolic rate, accumulated mitochondrial dysfunction, elevated cell signaling, and accelerated peroxisomal activities. This redox imbalance may regulate gene expression, alter protein stability, and modulate existing cellular programs, resulting in inefficient treatment modalities. Therapeutic strategies targeting intra- or extracellular redox states of cancer cells at varying state of progression may trigger programmed cell death if exceeded a certain threshold, enabling therapeutic selectivity and overcoming cancer resistance to radiotherapy and chemotherapy. Nanotechnology provides new opportunities for modulating redox state in cancer cells due to their excellent designability and high reactivity. Various nanomaterials are widely researched to enhance highly reactive substances (free radicals) production, disrupt the endogenous antioxidant defense systems, or both. Here, the physiological features of redox imbalance in cancer cells are described and the challenges in modulating redox state in cancer cells are illustrated. Then, nanomaterials that regulate redox imbalance are classified and elaborated upon based on their ability to target redox regulations. Finally, the future perspectives in this field are proposed. It is hoped this review provides guidance for the design of nanomaterials-based approaches involving modulating intra- or extracellular redox states for cancer therapy, especially for cancers resistant to radiotherapy or chemotherapy, etc.

Cancer cell membrane-coated nanoparticles: a promising anti-tumor bionic platform

Nanoparticle (NP) drug delivery systems have shown promise in tumor therapy. However, limitations such as susceptibility to immune clearance and poor targeting in a complex intercellular environment still exist. Recently, cancer cell membrane-encapsulated nanoparticles (CCM-NPs) constructed using biomimetic nanotechnology have been developed to overcome these problems. Proteins on the membrane surface of cancer cells can provide a wide range of activities for CCM-NPs, including immune escape and homologous cell recognition properties. Meanwhile, the surface of the cancer cell membrane exhibits obvious antigen enrichment, so that CCM-NPs can transmit tumor-specific antigen, activate a downstream immune response, and produce an effective anti-tumor effect. In this review, we first provided an overview of the functions of cancer cell membranes and summarized the preparation techniques and characterization methods of CCM-NPs. Then, we focused on the application of CCM-NPs in tumor therapy. In addition, we summarized the functional modifications of cancer cell membranes and compiled the patent applications related to CCM-NPs in recent years. Finally, we proposed the future challenges and directions of this technology in order to provide guidance for researchers in this field.

Advances in tumor vascular growth inhibition

Tumor growth and metastasis require neovascularization, which is dependent on a complex array of factors, such as the production of various pro-angiogenic factors by tumor cells, intercellular signaling, and stromal remodeling. The hypoxic, acidic tumor microenvironment is not only conducive to tumor cell proliferation, but also disrupts the equilibrium of angiogenic factors, leading to vascular heterogeneity, which further promotes tumor development and metastasis. Anti-angiogenic strategies to inhibit tumor angiogenesis has, therefore, become an important focus for anti-tumor therapy. The traditional approach involves the use of anti-angiogenic drugs to inhibit tumor neovascularization by targeting upstream and downstream angiogenesis-related pathways or pro-angiogenic factors, thereby inhibiting tumor growth and metastasis. This review explores the mechanisms involved in tumor angiogenesis and summarizes currently used anti-angiogenic drugs, including monoclonal antibody, and small-molecule inhibitors, as well as the progress and challenges associated with their use in anti-tumor therapy. It also outlines the opportunities and challenges of treating tumors using more advanced anti-angiogenic strategies, such as immunotherapy and nanomaterials.

Dressing and undressing MOF nanophotosensitizers to manipulate phototoxicity for precise therapy of tumors

Photodynamic therapy (PDT) is a clinically approved treatment for tumors, and it relies on the phototoxicity of photosensitizers by producing reactive oxygen species (ROS) to destroy cancer cells under light irradiation. However, such phototoxicity is a double-edged sword, which is also harmful to normal tissues. To manipulate phototoxicity and improve the therapy effect, herein we have proposed a dressing-undressing strategy for de-activating and re-activating therapy functions of photosensitizer nanoparticles. One kind of metal organic framework (PCN-224), which is composed of Zr(IV) cation and tetrakis (4-carboxyphenyl) porphyrin (TCPP), has been prepared as a model of photosensitizer, and it has size of ∼70 nm. These PCN-224 nanoparticles are subsequently coated with a mesoporous organic silica (MOS) shell containing tetrasulfide bonds (-S-S-S-S-), realizing the dressing of PCN-224. MOS shell has the thickness of ∼20 nm and thus can block 1O2 (diffusion distance: <10 nm), deactivating the phototoxicity and preventing the damage to skin and eyes. Furthermore, PCN-224@MOS can be used to load chemotherapy drug (DOX·HCl). When PCN-224@MOS-DOX are mixed with glutathione (GSH), MOS shell with -S-S-S-S- bonds can be reduced by GSH and then be decomposed, which results in the undressing and then confers the exposure of PCN-224 with good PDT function as well as the release of DOX. When PCN-224@MOS-DOX dispersion is injected into the mice and accumulated in the tumor, endogenous GSH also confers the undressing of PCN-224@MOS-DOX, realizing the in-situ activation of PDT and chemotherapy for tumor. Therefore, the present study not only demonstrates a general dressing-undressing strategy for manipulating phototoxicity of photosensitizers, but also provide some insights for precise therapy of tumors without side-effects. STATEMENT OF SIGNIFICANCE: Photosensitizers can generate reactive oxygen species (ROS) under light radiation to destroy cancer cells. However, this phototoxicity is a double-edged sword and also harmful to normal tissues such as the skin and eyes. To control phototoxicity and improve therapeutic efficacy, we prepared a PCN-224@MOS-DOX nanoplatform and proposed a dressing and undressing strategy to deactivate and reactivate the therapeutic function of the photosensitizer nanoparticles. The MOS shell can block the diffusion of 1O2, eliminate phototoxicity, and prevent damage to the skin and eyes. When injected into mice and accumulated in tumors, PCN-224@MOS-DOX dispersions are endowed with an endogenous GSH-driven undressing effect, achieving in situ activation of PDT and tumor chemotherapy.

PLGA nanomedical consignation: A novel approach for the management of prostate cancer

The malignancy of the prostate is a complicated ailment which impacts millions of male populations around the globe. Despite the multitude of endeavour accomplished within this domain, modalities that are involved in the ameliorative management of predisposed infirmity are still relent upon non-specific and invasive procedures, thus imposing a detrimental mark on the living standard of the individual. Also, the orchestrated therapeutic interventions are still incompetent in substantiating a robust and unabridged therapeutic end point owing to their inadequate solubility, low bioavailability, limited cell assimilation, and swift deterioration, thereby muffling the clinical application of these existing treatment modalities. Nanotechnology has been employed in an array of modalities for the medical management of malignancies. Among the assortment of available nano-scaffolds, nanocarriers composed of a bio-decomposable and hybrid polymeric material like PLGA hold an opportunity to advance as standard chemotherapeutic modalities. PLGA-based nanocarriers have the prospect to address the drawbacks associated with conventional cancer interventions, owing to their versatility, durability, nontoxic nature, and their ability to facilitate prolonged drug release. This review intends to describe the plethora of evidence-based studies performed to validate the applicability of PLGA nanosystem in the amelioration of prostate malignancies, in conjunction with PLGA focused nano-scaffold in the clinical management of prostate carcinoma. This review seeks to explore numerous evidence-based studies confirming the applicability of PLGA nanosystems in ameliorating prostate malignancies. It also delves into the role of PLGA-focused nano-scaffolds in the clinical management of prostate carcinoma, aiming to provide a comprehensive perspective on these advancements.

Recent advances in metal-organic frameworks for stimuli-responsive drug delivery

After entering the human body, drugs for treating diseases, which are prone to delivery and release in an uncontrolled manner, are affected by various factors. Based on this, many researchers utilize various microenvironmental changes encountered during drug delivery to trigger drug release and have proposed stimuli-responsive drug delivery systems. In recent years, metal-organic frameworks (MOFs) have become promising stimuli-responsive agents to release the loaded therapeutic agents at the target site to achieve more precise drug delivery due to their high drug loading, excellent biocompatibility, and high stimuli-responsiveness. The MOF-based stimuli-responsive systems can respond to various stimuli under pathological conditions at the site of the lesion, releasing the loaded therapeutic agent in a controlled manner, and improving the accuracy and safety of drug delivery. Due to the changes in different physical and chemical factors in the pathological process of diseases, the construction of stimuli-responsive systems based on MOFs has become a new direction in drug delivery and controlled release. Based on the background of the rapidly increasing attention to MOFs applied in drug delivery, we aim to review various MOF-based stimuli-responsive drug delivery systems and their response mechanisms to various stimuli. In addition, the current challenges and future perspectives of MOF-based stimuli-responsive drug delivery systems are also discussed in this review.

Design strategies for enhancing antitumor efficacy through tumor microenvironment exploitation using albumin-based nanosystems: A review

The tumor microenvironment (TME) is a complex and dynamic system that plays a crucial role in regulating cancer progression, treatment response, and the emergence of acquired resistance mechanisms. The TME is usually featured by severe hypoxia, low pH values, high hydrogen peroxide (H2O2) concentrations, and overproduction of glutathione (GSH). The current development of intelligent nanosystems that respond to TME has shown great potential to enhance the efficacy of cancer treatment. As one of the functional macromolecules explored in this field, albumin-based nanocarriers, known for their inherent biocompatibility, serves as a cornerstone for constructing diverse therapeutic platforms. In this paper, we present a comprehensive overview of the latest advancements in the design strategies of albumin nanosystems, aiming to enhance cancer therapy by harnessing various features of solid tumors, including tumor hypoxia, acidic pH, the condensed extracellular matrix (ECM) network, excessive GSH, high glucose levels, and tumor immune microenvironment. Furthermore, we highlight representative designs of albumin-based nanoplatforms by exploiting the TME that enhance a broad range of cancer therapies, such as chemotherapy, phototherapy, radiotherapy, immunotherapy, and other tumor therapies. Finally, we discuss the existing challenges and future prospects in direction of albumin-based nanosystems for the practical applications in advancing enhanced cancer treatments.

Nanoplatform-Mediated Autophagy Regulation and Combined Anti-Tumor Therapy for Resistant Tumors

The overall cancer incidence and death toll have been increasing worldwide. However, the conventional therapies have some obvious limitations, such as non-specific targeting, systemic toxic effects, especially the multidrug resistance (MDR) of tumors, in which, autophagy plays a vital role. Therefore, there is an urgent need for new treatments to reduce adverse reactions, improve the treatment efficacy and expand their therapeutic indications more effectively and accurately. Combination therapy based on autophagy regulators is a very feasible and important method to overcome tumor resistance and sensitize anti-tumor drugs. However, the less improved efficacy, more systemic toxicity and other problems limit its clinical application. Nanotechnology provides a good way to overcome this limitation. Co-delivery of autophagy regulators combined with anti-tumor drugs through nanoplatforms provides a good therapeutic strategy for the treatment of tumors, especially drug-resistant tumors. Notably, the nanomaterials with autophagy regulatory properties have broad therapeutic prospects as carrier platforms, especially in adjuvant therapy. However, further research is still necessary to overcome the difficulties such as the safety, biocompatibility, and side effects of nanomedicine. In addition, clinical research is also indispensable to confirm its application in tumor treatment.

Synergistic reinforcement of immunogenic cell death and transformation of tumor-associated macrophages via an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform

The immune system's role in tumor growth and spread has led to the importance of activating immune function in tumor therapy. We present a strategy using an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform (M1mDDTF) to synergistically reinforce immunogenic cell death (ICD) and transform tumor-associated macrophages (TAMs) against tumors. The M1mDDTF nanoparticles consist of doxorubicin-loaded dendritic mesoporous silica nanoparticles chelated with FeIII-tannic acid (FeIIITA) and coated with M1-type macrophage membranes. In the acidic tumor microenvironment, FeIIITA releases Fe2+ and generates ·OH, aided by near infrared irradiation for enhanced doxorubicin release. Furthermore, the M1mDDTF nanoplatform not only directly kills tumor cells but stimulates ICD, which can increase the proportion of CD86+ CD80+ cells and promote dendritic cell maturation. Particularly, the M1mDDTF nanoplatform can also promote the gradual polarization of TAMs into the M1-type and promote tumor cell killing. This study demonstrates the safety and multifunctionality of M1mDDTF nanoparticles, highlighting their potential for clinical tumor treatment. STATEMENT OF SIGNIFICANCE: Malignant tumors are a global concern and a major cause of death. Nanoparticles' passive targeting is ineffective and hindered by reticuloendothelial system clearance. Therefore, enhancing nanoparticle accumulation in tumors while minimizing toxicity is a challenge. Coating nanoparticles with cell membranes enhances biocompatibility, immune evasion, and specific targeting. This approach has led to the development of numerous cell membrane-mimicking nanomaterials with remarkable properties and functions. This study developed an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform, boosting immunogenic cell death and transforming tumor-associated macrophages. Tannic acid in the tumor microenvironment reduced Fe3+ to Fe2+, generating ·OH. M1mDDTF nanosystem induced M1-type macrophage polarization, inhibiting tumor growth and triggering immune cell death. Safe and versatile, these M1mDDTF nanoparticles hold promise for clinical tumor treatment.

Porphyrin Derivative with Binary Properties of Photodynamic Therapy and Water-Dependent Reversible Photoacidity Therapy for Treating Hypoxic Tumor

Porphyrin photosensitizers are the classic drugs in clinical photodynamic therapy (PDT), but the hypoxia of tumor environment and the rapid oxygen consumption of PDT severely weaken their therapeutic effect. A recently reported water-dependent reversible photoacidity therapy (W-RPAT) is O2 -independence, providing a solution for the treatment of hypoxic tumors. In this work, TPP-O-PEG5, a porphyrin derivative with binary properties of PDT and W-RPAT, is designed and synthesized for the first time. The nanoparticles (NPs) of TPP-O-PEG5 encapsulated with DSPE-mPEG2000, an amphiphilic polymer approved by Food and Drug Administration, can simultaneously produce reactive oxygen species and H+ under irradiation of a 660 nm laser, and revert the H+ back under darkness, presenting strong phototoxicity to multiple tumor cell lines with no obvious difference between the IC50 values tested under normoxic (≈20% O2 ) and hypoxic (<0.5% O2 ) conditions. Excitingly, in vivo experiments show that the therapeutic effect of TPP-O-PEG5 NPs on large hypoxic tumors is better than that of NPe6, a clinical porphin PDT drug. This work provides a novel strategy for porphyrin photosensitizers to break through the limitation of hypoxic environment, and significantly improve the phototherapeutic effect on hypoxic tumors.

Tumor Targeting with Apatinib-loaded Nanoparticles and Sonodynamic Combined Therapy

INTRODUCTION

This study implies the enhancement of apatinib killing effect in 4T1 tumor cells through constructing drug-loaded nanoparticles apatinib/Ce6@ZIF- 8@Membranes (aCZM) to enhance tumor therapeutic targeting and reduce toxic side following sonodynamic therapy (SDT).

METHODS

apatinib/Ce6@ZIF-8 (aCZ) were synthesized by in situ encapsulation, and aCZM were constructed by encapsulating the nanoparticles with extracted breast cancer 4T1 cell membranes. aCZM were characterized and tested for the stability by electron microscopy, and the membrane proteins on the nanoparticles' surface were assessed using SDS-PAGE gel electrophoresis. The cell viability of 4T1 cells following treatment with aCZM was tested using cell counting kit-8 (CCK-8). The uptake of nanoparticles was detected by laser confocal microscopy and flow cytometry, and the SDT-mediated production of reactive oxygen species (ROS) was verified by singlet oxygen sensor green (SOSG), electron spin resonance (ESR), and DCFH-DA fluorescent probes. The CCK-8 assay and flow cytometry using Calcein/PI were used to assess the antitumoral effect of aCZM nanoparticles under SDT. The biosafety of aCZM was further verified in vitro and in vivo using the hemolysis assay, routine blood test and H&E staining of vital organs in Balb/c mice.

RESULTS

aCZM with an average particle size of about 210.26 nm were successfully synthesized. The results of the SDS-PAGE gel electrophoresis experiment showed that aCZM have a band similar to that of pure cell membrane proteins. The CCK-8 assay demonstrated the absence of effects on cell viability at a low concentration range, and the relative cell survival rate reached more than 95%. Laser confocal microscopy and flow cytometry analysis showed that aCZM treated group has the strongest fluorescence and the highest cellular uptake of nanoparticles. SOSG, ESR, and DCFH-DA fluorescent probes all indicated that the aCZM + SDT treated group has the highest ROS production. The CCK-8 assay also showed that when the ultrasound intensity was fixed at 0.5 W/cm2, the relative cell survival rates in the medium concentration group (10 μg/ml) (5.54 ± 1.26%) and the high concentration group (20 μg/ml) (2.14 ± 1.63%) were significantly lower than those in the low concentration group (5 μg/ml) (53.40 ± 4.25%). Moreover, there was a concentration and intensity dependence associated with the cellkilling effect. The mortality rate of the aCZM in the ultrasound group (44.95 ± 3.03%) was significantly higher than that of the non-ultrasound (17.00 ± 2.26%) group and aCZ + SDT group (24.85 ± 3.08%) (P<0.0001). The live and dead cells' staining (Calcein/PI) also supported this result. Finally, in vitro hemolysis test at 4 and 24 hours showed that the hemolysis rate of the highest concentration group was less than 1%. The blood routine, biochemistry, and H&E staining results of major organs in Balb/c mice undergoing nano-treatments showed no obvious functional abnormalities and tissue damage in 30 days.

CONCLUSION

In this study, a multifunctional bionic drug delivery nanoparticles (aCZM) system with good biosafety and compatibility in response to acoustic dynamics was successfully constructed and characterized. This system enhanced apatinib killing effect on tumor cells and reduced toxic side effects under SDT.

pH-Responsive NIR-II phototheranostic agents for in situ tumor vascular monitoring and combined anti-vascular/photothermal therapy

Developing nanoplatforms integrating superior fluorescence imaging ability in second near-infrared (NIR-II) window and tumor microenvironment responsive multi-modal therapy holds great potential for real-time feedback of therapeutic efficacy and optimizing tumor inhibition. Herein, we developed a pH-sensitive pyrrolopyrrole aza-BODIPY-based amphiphilic molecule (PTG), which has a balanced NIR-II fluorescence brightness and photothermal effect. PTG is further co-assembled with a vascular disrupting agent (known as DMXAA) to prepare PTDG nanoparticles for combined anti-vascular/photothermal therapy and real-time monitoring of the tumor vascular disruption. Each PTG molecule has an active PT-3 core which is linked to two PEG chains via pH-sensitive ester bonds. The cleavage of ester bonds in the acidic tumor environment would tricker releases of DMXAA for anti-vascular therapy and further assemble PT-3 cores into micrometer particles for long term monitoring of the tumor progression. Furthermore, benefiting from the high brightness in the NIR-II region (119.61 M-1 cm-1) and long blood circulation time (t1/2 = 235.6 min) of PTDG nanoparticles, the tumor vascular disrupting process can be in situ visualized in real time during treatment. Overall, this study demonstrates a self-assembly strategy to build a pH-responsive NIR-II nanoplatform for real-time monitoring of tumor vascular disruption, long-term tracking tumor progression and combined anti-vascular/photothermal therapy.

Rationally Integrated Precise ER-Targeted and Oxygen-Compensated Photodynamic Immunostimulant for Immunogenicity-Boosted Tumor Therapy

Notwithstanding that immunotherapy has made eminent clinical breakthroughs, activating the immunogenicity and breaking the immunosuppressive tumor microenvironment (ITME) remains tempting yet challenging. Herein, a customized-designed immunostimulant is engineered for attenuating ITME and eliciting an immune response to address this challenge head-on. This immunostimulant is equipped with dual silica layers coated upconversion nanoparticles (UCNPs) as nanocarriers modified with endoplasmic reticulum (ER)-targeted molecular N-p-Tosylglycine, in which the dense silica for chlorin e6 (Ce6) and the glutathione (GSH)-responsive degradable silica for loading resveratrol (RES) - (UCSMRER ). On the one hand, this precise ER-targeted photodynamic therapy (PDT) can generate reactive oxygen species (ROS) in situ under the 980 nm laser irradiation, which not only induced severe cell death directly but also caused intense ER stress-based immunogenic cell death (ICD). On the other hand, tumor hypoxia aggravated by the PDT is alleviated by RES released on-demand, which reduced oxygen consumption by impairing the mitochondrial electron transport chain (ETC). This integrated precise ER-targeted and oxygen-compensated strategy maximized the PDT effect and potentiated ICD-associated immunotherapy, which availed to attenuate ITME, activate tumor immunogenicity, and further magnify the anti-tumor effect. This innovative concept about PDT and immunotherapy sheds light on cancer-related clinical application.

Redox-active polyphenol nanoparticles deprive endogenous glutathione of electrons for ROS generation and tumor chemodynamic therapy

Chemodynamic therapy (CDT) based on generating reactive oxygen species (ROS) is promising for cancer treatment. However, the intrinsic H2O2 is deficient for CDT, and glutathione (GSH) eliminates ROS to protect tumor cells from ROS cytotoxicity. Herein, we propose a strategy to switch the electron flow direction of GSH for O2 reduction and ROS generation rather than ROS clearance by using P(DA-Fc) nanoparticles, which are polymerized from ferrocenecarboxylic acid (Fc) coupled dopamine. P(DA-Fc) NPs with phenol-quinone conversion ability mimic NOX enzyme to deprive electrons from GSH to reduce O2 for H2O2 generation; the following •OH release can be triggered by Fc. Semiquinone radicals in P(DA-Fc) are significantly enhanced after GSH treatment, further demonstrated with strong single-electron reduction ability by calculation. In vitro and in vivo experiments indicate that P(DA-Fc) can consume intrinsic GSH to produce endogenous ROS; ROS generation strongly depends on GSH/pH level and eventually causes tumor cell death. Our work makes the first attempt to reverse the function of GSH from ROS scavenger to ROS producer, explores new roles of PDA-based nanomaterials in CDT beyond photothermal reagents and drug carriers, and provides a new strategy to improve the efficiency of CDT. STATEMENT OF SIGNIFICANCE: P(DA-Fc) nanoparticles performing tumor microenvironment response capacity and tumor reductive power utilize ability were fabricated for CDT tumor suppression. After endocytosis by tumor cells, P(DA-Fc) deprived GSH of electrons for H2O2 and •OH release, mimicking the intrinsic ROS production conducted by NADPH, further inducing tumor cell necrosis and apoptosis. Our work makes the first attempt to reverse the function of GSH from ROS scavenger to producer, explores new functions of PDA-based nanomaterials in CDT beyond photothermal reagents and drug carriers, and provides a new strategy to improve CDT efficiency.

DNA-Functionalized Porphyrinic Metal-Organic Framework-Based Drug Delivery System for Targeted Bimodal Cancer Therapy

A DNA-functionalized porphyrinic MOF (porMOF) drug delivery system was successfully constructed. porMOF as a photosensitizer and drug delivery carrier can integrate photodynamic therapy (PDT) and chemotherapy. Via the strong coordination interaction between the zirconium cluster of porMOF and the terminal phosphate group of DNA, the stable modification of the DNA layer on the porMOF surface is achieved. Meanwhile, the introduction of C/G-rich base pairs into the DNA double-stranded structure provides more binding sites of chemotherapeutic drug doxorubicin (DOX). AS1411, an aptamer of nucleolin proteins that are overexpressed by cancer cells, is introduced in the double-stranded terminal, which can endow the nanosystem with the ability to selectively recognize cancer cells. C-rich sequences in DNA double strands form an i-motif structure under acidic conditions to promote the highly efficient release of DOX in cancer cells. In vitro and in vivo experiments demonstrate that the synergistic PDT/chemotherapy modality achieves highly efficient cancer cell killing and tumor ablation without undesirable side effects.

Construction of Core-Shell MOF CSMnP with Enzyme-Like Activity for Chemotherapy and Chemodynamic Therapy

Materials with enzyme-like activity have received a lot of attention in the field of tumor catalytic therapy. Here, biocompatible core-shell MOF CSMnP with two valence states of Mn ion, which could process chemodynamic therapy (CDT), was designed and synthesized. Besides, it could also promote a series of catalytic processes in the tumor microenvironment (TME). CSMnP catalyzed endogenous hydrogen peroxide (H2O2) to oxygen (O2) via catalase-like activity and then combined with the outer layer Mn(II)-PBC to convert O2 into superoxide radicals (•O2-), exhibiting oxidase-like activity. Besides, intracellular glutathione (GSH) could be effectively consumed through the glutathione oxidase-like activity of Mn3+. The occurrence of the cascade reactions effectively amplified the enzymatic production to enhance CDT. Furthermore, the therapeutic effect of CSMnP was improved through the loading of cationic drug DOX. The loading capacity was 11.10 wt %, which was 2.2 times that of Mn(III)-PBC (4.95 wt %), and the release of DOX showed a characteristic response. Therefore, the core-shell MOF with enzyme-like activity had a potential application for tumor combination therapy.

Nanoscale Metal-Organic Frameworks Combined with Metal Nanoparticles and Metal Oxide/Peroxide to Relieve Tumor Hypoxia for Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) is a clinically approved noninvasive tumor therapy that can selectively kill malignant tumor cells, with promising use in the treatment of various cancers. PDT is typically composed of three important parts: the specific wavelength of light, photosensitizer (PS), and oxygen. With the progressing investigation on PDT treatment, the most recent attention has focused on improving photodynamic efficiency. Tumor hypoxia has always been a critical factor hindering the efficacy of PDT. Nanoscale metal-organic frameworks (nMOF), the fourth generation of PS, present great potential in photodynamic therapy. In particular, nMOF combined with metal nanoparticles and metal oxide/peroxide has demonstrated unique properties for enhanced PDT. The metal and metal oxide nanoparticles can catalyze H2O2 to generate oxygen or automatically produces oxygen, alleviating the hypoxia and improving the photodynamic efficiency. Metal peroxide nanoparticles can spontaneously produce oxygen in water or under acidic conditions. Therefore, this Review summarizes the recent development of nMOF combined with metal nanoparticles (platinum nanoparticles and gold nanoparticles) and metal oxide/peroxide (manganese dioxide, ferric oxide, cerium oxide, calcium peroxide, and magnesium peroxide) for enhanced photodynamic therapy by alleviating tumor hypoxia. Finally, future perspectives of nMOF combined nanomaterials in PDT are put forward.

MnO2 Decorated Metal-Organic Framework-Based Hydrogel Relieving Tumor Hypoxia for Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) has emerged as a promising cancer treatment modality; however, its therapeutic efficacy is greatly limited by tumor hypoxia. In this study, a metal-organic framework (MOF)-based hydrogel (MOF Gel) system that synergistically combines PDT with the supply of oxygen is designed. Porphyrin-based Zr-MOF nanoparticles are synthesized as the photosensitizer. MnO2 is decorated onto the surface of the MOF, which can effectively convert H₂O₂ into oxygen. Simultaneously, the incorporation of MnO2 -decorated MOF (MnP NPs) into a chitosan hydrogel (MnP Gel) serves to enhance its stability and retention at the tumor site. The results show that this integrated approach significantly improves tumor inhibition efficiency by relieving tumor hypoxia and enhancing PDT. Overall, the findings underscore the potential for employing nano-MOF-based hydrogel systems as promising agents for cancer therapy, thus advancing the application of multifunctional MOFs in cancer treatment.

Genetically engineered nanovesicles mobilize synergistic antitumor immunity by ADAR1 silence and PDL1 blockade

Growing evidence has proved that RNA editing enzyme ADAR1, responsible for detecting endogenous RNA species, was significantly associated with poor response or resistance to immune checkpoint blockade (ICB) therapy. Here, a genetically engineered nanovesicle (siAdar1-LNP@mPD1) was developed as an RNA interference nano-tool to overcome tumor resistance to ICB therapies. Small interfering RNA against ADAR1 (siAdar1) was packaged into a lipid nanoparticle (LNP), which was further coated with plasma membrane extracted from the genetically engineered cells overexpressing PD1. siAdar1-LNP@mPD1 could block the PD1/PDL1 immune inhibitory axis by presenting the PD1 protein on the coating membranes. Furthermore, siAdar1 could be effectively delivered into cancer cells by the designed nanovesicle to silence ADAR1 expression, resulting in an increased type I/II interferon (IFN-β/γ) production and making the cancer cells more sensitive to secreted effector cytokines such as IFN-γ with significant cell growth arrest. These integrated functions confer siAdar1-LNP@mPD1 with robust and comprehensive antitumor immunity, as evidenced by significant tumor growth regression, abscopal tumor prevention, and effective suppression of lung metastasis, through a global remodeling of the tumor immune microenvironment. Overall, we provided a promising translatable strategy to simultaneously silence ADAR1 and block PDL1 immune checkpoint to boost robust antitumor immunity.

Intelligent nanomaterials for cancer therapy: recent progresses and future possibilities

Intelligent nanomedicine is currently one of the most active frontiers in cancer therapy development. Empowered by the recent progresses of nanobiotechnology, a new generation of multifunctional nanotherapeutics and imaging platforms has remarkably improved our capability to cope with the highly heterogeneous and complicated nature of cancer. With rationally designed multifunctionality and programmable assembly of functional subunits, the in vivo behaviors of intelligent nanosystems have become increasingly tunable, making them more efficient in performing sophisticated actions in physiological and pathological microenvironments. In recent years, intelligent nanomaterial-based theranostic platforms have showed great potential in tumor-targeted delivery, biological barrier circumvention, multi-responsive tumor sensing and drug release, as well as convergence with precise medication approaches such as personalized tumor vaccines. On the other hand, the increasing system complexity of anti-cancer nanomedicines also pose significant challenges in characterization, monitoring and clinical use, requesting a more comprehensive and dynamic understanding of nano-bio interactions. This review aims to briefly summarize the recent progresses achieved by intelligent nanomaterials in tumor-targeted drug delivery, tumor immunotherapy and temporospatially specific tumor imaging, as well as important advances of our knowledge on their interaction with biological systems. In the perspective of clinical translation, we have further discussed the major possibilities provided by disease-oriented development of anti-cancer nanomaterials, highlighting the critical importance clinically-oriented system design.

Mesenchymal Stem Cell Membrane-Coated TPCS2a-Loaded Nanoparticles for Breast Cancer Photodynamic Therapy

Despite substantial improvements in breast cancer (BC) treatment there is still an urgent need to find alternative treatment options to improve the outcomes for patients with advanced-stage disease. Photodynamic therapy (PDT) is gaining a lot of attention as a BC therapeutic option because of its selectivity and low off-target effects. However, the hydrophobicity of photosensitizers (PSs) impairs their solubility and limits the circulation in the bloodstream, thus representing a major challenge. The use of polymeric nanoparticles (NPs) to encapsulate the PS may represent a valuable strategy to overcome these issues. Herein, we developed a novel biomimetic PDT nanoplatform (NPs) based on a polymeric core of poly(lactic-co-glycolic)acid (PLGA) loaded with the PS meso-tetraphenylchlorin disulfonate (TPCS_2a). TPCS_2a@NPs of 98.89 ± 18.56 nm with an encapsulation efficiency percentage (EE%) of 81.9 ± 7.92% were obtained and coated with mesenchymal stem cells-derived plasma membranes (mMSCs) (mMSC-TPCS_2a@NPs, size of 139.31 ± 12.94 nm). The mMSC coating armed NPs with biomimetic features to impart long circulation times and tumor-homing capabilities. In vitro, biomimetic mMSC-TPCS_2a@NPs showed a decrease in macrophage uptake of 54% to 70%, depending on the conditions applied, as compared to uncoated TPCS_2a@NPs. Both NP formulations efficiently accumulated in MCF7 and MDA-MB-231 BC cells, while the uptake was significantly lower in normal breast epithelial MCF10A cells with respect to tumor cells. Moreover, encapsulation of TPCS_2a in mMSC-TPCS_2a@NPs effectively prevents its aggregation, ensuring efficient singlet oxygen (¹O₂) production after red light irradiation, which resulted in a considerable in vitro anticancer effect in both BC cell monolayers (IC₅₀ < 0.15 µM) and three-dimensional spheroids.

Smart Nanomaterials in Cancer Theranostics: Challenges and Opportunities

Cancer is ranked as the second leading cause of death globally. Traditional cancer therapies including chemotherapy are flawed, with off-target and on-target toxicities on the normal cells, requiring newer strategies to improve cell selective targeting. The application of nanomaterial has been extensively studied and explored as chemical biology tools in cancer theranostics. It shows greater applications toward stability, biocompatibility, and increased cell permeability, resulting in precise targeting, and mitigating the shortcomings of traditional cancer therapies. The nanoplatform offers an exciting opportunity to gain targeting strategies and multifunctionality. The advent of nanotechnology, in particular the development of smart nanomaterials, has transformed cancer diagnosis and treatment. The large surface area of nanoparticles is enough to encapsulate many molecules and the ability to functionalize with various biosubstrates such as DNA, RNA, aptamers, and antibodies, which helps in theranostic action. Comparatively, biologically derived nanomaterials perceive advantages over the nanomaterials produced by conventional methods in terms of economy, ease of production, and reduced toxicity. The present review summarizes various techniques in cancer theranostics and emphasizes the applications of smart nanomaterials (such as organic nanoparticles (NPs), inorganic NPs, and carbon-based NPs). We also critically discussed the advantages and challenges impeding their translation in cancer treatment and diagnostic applications. This review concludes that the use of smart nanomaterials could significantly improve cancer theranostics and will facilitate new dimensions for tumor detection and therapy.

Cloaking Mesoporous Polydopamine with Bacterial Membrane Vesicles to Amplify Local and Systemic Antitumor Immunity

As adjuvants or antigens, bacterial membranes have been widely used in recent antibacterial and antitumor research, but they are often injected multiple times to achieve therapeutic outcomes, with limitations in biosafety and clinical application. Herein, we leverage the biocompatibility and immune activation capacity of Salmonella strain VNP20009 to produce double-layered membrane vesicles (DMVs) for enhanced systemic safety and antitumor immunity. Considering the photothermal effect of polydopamine upon irradiation, VNP20009-derived DMVs are prepared to coat the surface of mesoporous polydopamine (MPD) nanoparticles, leading to the potential synergies between photothermal therapy mediated by MPD and immunotherapy magnified by DMVs. The single dose of MPD@DMV can passively target tumors and activate the immune system with upregulated T cell infiltration and secretion levels of pro-inflammatory factors as well as antitumor related cytokines. All of these promoted immune responses result in malignant melanoma tumor regression and extended survival time on local or distant tumor-bearing mouse models. Importantly, we further explore the advantages of intravenous injection of the MPD@DMV agent compared with its intratumoral injection, and the former demonstrates better long-term immune effects on animal bodies. Overall, this formulation design brings broader prospects for the autologous vaccine adjuvant by bacterial membrane vesicles in cancer therapy.

Engineering Cell Membrane-Cloaked Catalysts as Multifaceted Artificial Peroxisomes for Biomedical Applications

Artificial peroxisomes (APEXs) or peroxisome mimics have caught a lot of attention in nanomedicine and biomaterial science in the last decade, which have great potential in clinically diagnosing and treating diseases. APEXs are typically constructed from a semipermeable membrane that encloses natural enzymes or enzyme-mimetic catalysts to perform peroxisome-/enzyme-mimetic activities. The recent rapid progress regarding their biocatalytic stability, adjustable activity, and surface functionality has significantly promoted APEXs systems in real-life applications. In addition, developing a facile and versatile system that can simulate multiple biocatalytic tasks is advantageous. Here, the recent advances in engineering cell membrane-cloaked catalysts as multifaceted APEXs for diverse biomedical applications are highlighted and commented. First, various catalysts with single or multiple enzyme activities have been introduced as cores of APEXs. Subsequently, the extraction and function of cell membranes that are used as the shell are summarized. After that, the applications of these APEXs are discussed in detail, such as cancer therapy, antioxidant, anti-inflammation, and neuron protection. Finally, the future perspectives and challenges of APEXs are proposed and outlined. This progress review is anticipated to provide new and unique insights into cell membrane-cloaked catalysts and to offer significant new inspiration for designing future artificial organelles.

Nanomaterial-Based Antivascular Therapy in the Multimodal Treatment of Cancer

Abnormal tumor vasculature and a hypoxic tumor microenvironment (TME) limit the effectiveness of conventional cancer treatment. Recent studies have shown that antivascular strategies that focus on antagonizing the hypoxic TME and promoting vessel normalization effectively synergize to increase the antitumor efficacy of conventional therapeutic regimens. By integrating multiple therapeutic agents, well-designed nanomaterials exhibit great advantages in achieving higher drug delivery efficiency and can be used as multimodal therapy with reduced systemic toxicity. In this review, strategies for the nanomaterial-based administration of antivascular therapy combined with other common tumor treatments, including immunotherapy, chemotherapy, phototherapy, radiotherapy, and interventional therapy, are summarized. In particular, the administration of intravascular therapy and other therapies with the use of versatile nanodrugs is also described. This review provides a reference for the development of multifunctional nanotheranostic platforms for effective antivascular therapy in combined anticancer treatments.

Metal-Organic Frameworks Applications in Synergistic Cancer Photo-Immunotherapy

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

DDTC-Cu(I) based metal-organic framework (MOF) for targeted melanoma therapy by inducing SLC7A11/GPX4-mediated ferroptosis

Disulfiram (DSF), a drug for alcohol withdrawal, has attracted extensive scientific attention due to its potential to treat cancer. The metabolite of DSF, diethyl dithiocarbamate (DDTC), forms a Cu-DDTC complex in vivo with copper ions, which has been shown to be a proteasome inhibitor with high antitumor activity. However, the in vivo stability of Cu-DDTC complexes remains a challenge. In this study, the nanomedicine Cu-BTC@DDTC with high antitumor activity was prepared by using the nanoscale metal-organic framework (MOF) Cu-BTC as a carrier and loading diethyldithiocarbamate (DDTC) through coordination interaction. The results showed that Cu-BTC@DDTC had high drug loading and adequate stability, and exhibited DDTC-Cu(I) chemical valence characteristics and polycrystalline structure features. In vitro cytocompatibility investigation and animal xenograft tumor model evaluation demonstrated the anti-cancer potential of Cu-BTC@DDTC, especially the combination of Cu-BTC@DDTC with low-dose cisplatin showed significant antitumor effect and biosafety. This study provides a feasible protocol for developing antitumor drugs based on the drug repurposing strategy.

Biodegradable silica nanocapsules enable efficient nuclear-targeted delivery of native proteins for cancer therapy

Cell nucleus is the desired subcellular organelle of many therapeutic drugs. Although numerous nanomaterial-based methods have been developed which could facilitate nuclear-targeted delivery of small-molecule drugs, few are known to be capable of delivering exogenous native proteins. Herein, we report a convenient and highly robust approach for effective nuclear-targeted delivery of native proteins/antibodies by using biodegradable silica nanocapsules (BSNPs) that were surface-modified with different nuclear localization signals (NLS) peptides. We found that, upon gaining entry to mammalian cells via endocytosis, such nanocapsules (protein@BSNP-NLS) could effectively escape from endolysosomal vesicles with the assistance of an endosomolytic peptide (i.e., L17E), accumulate in cell nuclei and release the encapsulated protein cargo with biological activities. Cloaked with HeLa cell membrane, DNase@BSNP-NLS/L17E-M (with L17E encapsulated) homologously delivered functional proteins to cancer cell nuclei in tumor-xenografted mice. In vitro and in vivo anti-tumor properties, such as long blood circulation time and effective tumor growth inhibition, indicate that the nuclear-targeted cell-membrane-cloaked BSNPs (DNase@BSNP-NLS/L17E-M) platform is a promising therapeutic approach to nuclear related diseases.

Ratiometric singlet oxygen self-detecting and oxygen self-supplying nanosensor for real-time photodynamic therapy feedback and therapeutic effect enhancement

Integration of singlet oxygen (¹O₂) detection that provides necessary therapeutic feedback into nanotheranostics for hypoxic tumor photodynamic therapy (PDT) is desirable but still challenging. Herein, we report a nanosensor (denominated PAPD) by combining dual-channel ratiometric sensing and oxygen-augmenting strategies, which synergistically realizes real-time ¹O₂ self-detection, O₂ self-supply and enhanced phototherapy. PAPD nanosensor is constructed by encapsulating anthracene-based ¹O₂ sensitive fluorophore (DPA) into porphyrin metal-organic frameworks (PCN-224), decorating gold nanoparticles (AuNPs) as nanoenzymes, and coating polyethylene glycol thiol (PEG-SH) by the Au-S bond. PCN-224 serves as ¹O₂ reference fluorescence (FL) agent and photosensitizer. Once PCN-224-induced ¹O₂ is synthesized, the dual-channel ratiometric FL signal of PAPD actualizes sensitive, accurate and dynamic ¹O₂ visualization and gives real-time therapeutic information correlated with the therapeutic progression. Additionally, the catalase-like activity of PAPD possesses in situ O₂ production via intracellular H₂O₂ decomposition and accelerates ¹O₂ yields for amplifying the tumor cell killing efficiency. Moreover, the ratiometric ¹O₂ self-detection affords the capacity to evaluate the O₂ self-supplying effect in tumor 4T1 cells. Consequently, the rational-designed nanosensor PAPD provides a paradigm for real-time therapeutic evaluation and precise hypoxic tumor treatment clinically.

Photothermal Enhanced and Tumor Microenvironment Responsive Nanozyme for Amplified Cascade Enzyme Catalytic Therapy

Nanocatalysts, a class of nanomaterials with intrinsic enzyme-like activities, have been widely investigated for cancer catalytic therapy in recent years. However, precise construction of nanocatalysts with excellent enzyme catalytic activity and biosafety for tumor therapy still remains challenging. Here, a biodegradable nanocatalyst, PEGylated Cu_x Mn_y S_z (PCMS), is reported that can promote cascade catalytic reactions in tumor microenvironment (TME) while confining off-target side effects on normal tissues. PCMS not only catalyzes the cascade conversion of endogenous hydrogen peroxide (H₂ O₂ ) to oxygen (O₂ ) via catalase-like activity and then to superoxide radical (·O₂ ^- ) via oxidase-like activity in the TME, but also effectively depletes intracellular glutathione via glutathione oxidase-like activity. The cascade catalytic reactions, by taking advantage of high H₂ O₂ level in tumor cells, result in an enhanced enzyme catalytic effect in generation of ·O₂ ^- . More importantly, PCMS exhibits prominent photothermal effect under NIR-II 1064 nm laser irradiation that can further enhance chemodynamic therapy (CDT) efficacy in tumors. In addition, the biodegradation in TME and excellent photothermal effect of PCMS are beneficial to magnetic resonance imaging, photoacoustic imaging and infrared thermal imaging, resulting in tracing the fate of PCMS in vivo. This study provides a new tool for rational design of TME-responsive nanocatalysts with high biocompatibility for tumor catalytic therapy.

In situ forming oxygen/ROS-responsive niche-like hydrogel enabling gelation-triggered chemotherapy and inhibition of metastasis

Though the development of the diverse hypoxia-activated prodrugs (HAPs) has made great progresses in the last several decades, current cancer therapy based on HAPs still suffers many obstacles, e.g., poor therapeutic outcome owing to hard deep reaching to hypoxic region, and the occurrence of metastasis due to hypoxia. Inspired by engineered niches, a novel functional chitosan polymer (CS-FTP) is synthesized for construction of a hydrogel-based bio-niche (CS-FTP-gel) in aiming at remodeling tumor hypoxic microenvironment. The CS-FTP polymers are crosslinked to form a niche-like hydrogel via enzyme-mediated oxygen-consumable dimerization after injected into tumor, in which a HAP (i.e., AQ4N) could be physically encapsulated, resulting in enhanced tumor hypoxia to facilitate AQ4N-AQ4 toxic transformation for maximizing efficacy of chemotherapy. Furthermore, Pazopanib (PAZ) conjugated onto the CS backbone via ROS-sensitive linker undergoes a stimuli-responsive release behavior to promote antiangiogenesis for tumor starvation, eventually contributing to the inhibition of lung metastasis and synergistic action with AQ4N-based chemotherapy for an orthotopic 4T1 breast tumor model. This study provides a promising strategy for hypoxia-based chemotherapy and demonstrates an encouraging clinical potential for multifunctional hydrogel applicable for antitumor treatment.

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CS-FTP shows enzyme-mediated hypoxia-inducible gelation and reactive oxygen species (ROS)-responsive drug release.

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CS-FTP gel formed intratumorally can be used as a bio-niche to enhance tumor hypoxic microenvironment.

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In vivo PET/CT directly monitors the tumor hypoxia changes and confirm the ability of CS-FTP to enhance tumor hypoxia.

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Oxygen-consumable gelation of ROS-responsive CS-FTP triggers chemotherapy and starvation therapy for antimetastasis.

Manipulate tumor hypoxia for improved photodynamic therapy using nanomaterials

Due to its low adverse effects, minimal invasiveness, and outstanding patient compliance, photodynamic therapy (PDT) has drawn a great deal of interest, which is achieved through incomplete reduction of O₂ by a photosensitizer under light illumination that produces amounts of reactive oxygen species (ROS). However, tumor hypoxia significantly hinders the therapeutic effect of PDT so that tumor cells cannot be eliminated, which results in tumor cells proliferating, invading, and metastasizing. Additionally, O₂ consumption during PDT exacerbates hypoxia in tumors, leading to several adverse events after PDT treatment. In recent years, various investigations have focused on conquering or using tumor hypoxia by nanomaterials to amplify PDT efficacy, which is summarized in this review. This comprehensive review's objective is to present novel viewpoints on the advancement of oxygenation nanomaterials in this promising field, which is motivated by hypoxia-associated anti-tumor therapy.

Multifunctional biomimetic nanoplatform based on photodynamic therapy and DNA repair intervention for the synergistic treatment of breast cancer

Photodynamic therapy (PDT) is a minimally invasive and locally effective treatment method, which has been used in the clinical treatment of a variety of superficial tumors. In recent years, PDT has received extensive attention due to its induction of immunogenic cell death (ICD). However, the repair mechanism of tumor cells and low immune response limit the further development of PDT. To this end, a multifunctional biomimetic nanoplatform 4T1Mem@PGA-Ce6/Ola (MPCO) is developed to co-deliver the photosensitizer Chlorin e6 (Ce6) and Olaparib (Ola) with the function of preventing DNA repair. The nanoplatform shows efficient tumor targeting and cellular internalization properties due to cell membrane camouflage, and Ce6 and Ola produce a significant synergistic anti-tumor effect under laser irradiation. Meanwhile, the nanoplatform can also activate the cyclic guanosine monophosphate-adenosine monophosphate synthase-interferon gene stimulator signaling (cGAS-STING) pathway to produce cytokines. The damage-associated molecular patterns induced by ICD can work with these cytokines to recruit and stimulate the maturation of dendritic cells and induce the systemic anti-tumor immune response. Overall, this multifunctional biomimetic nanoplatform integrating PDT, chemotherapy, and immunotherapy is highlighted here to boost anti-tumor therapy. STATEMENT OF SIGNIFICANCE: Self-repair of DNA damage is the most important reason for the failure of primary tumor eradication and the formation of secondary and metastatic tumors. To address this issue, a multifunctional biomimetic nanoplatform 4T1Mem@PGA-Ce6/Ola (MPCO) was developed to integrate a photosensitizer Chlorine a6 and a poly (ADP-ribose) polymerase inhibitor Olaparib. With tumor targeting ability and controlled release of drugs, the MPCO was expected to enhance tumor immunogenicity and facilitate antitumor immunity through the induction of immunogenic cell death as well as the activation of the cGAS-STING pathway. This study develops a promising combination strategy against tumors and has substantial implications for the prognosis of patients with breast cancer.

Innovative nanotheranostics: Smart nanoparticles based approach to overcome breast cancer stem cells mediated chemo- and radioresistances

The alarming increase in the number of breast cancer patients worldwide and the increasing death rate indicate that the traditional and current medicines are insufficient to fight against it. The onset of chemo- and radioresistances and cancer stem cell-based recurrence make this problem harder, and this hour needs a novel treatment approach. Competent nanoparticle-based accurate drug delivery and cancer nanotheranostics like photothermal therapy, photodynamic therapy, chemodynamic therapy, and sonodynamic therapy can be the key to solving this problem due to their unique characteristics. These innovative formulations can be a better cargo with fewer side effects than the standard chemotherapy and can eliminate the stability problems associated with cancer immunotherapy. The nanotheranostic systems can kill the tumor cells and the resistant breast cancer stem cells by novel mechanisms like local hyperthermia and reactive oxygen species and prevent tumor recurrence. These theranostic systems can also combine with chemotherapy or immunotherapy approaches. These combining approaches can be the future of anticancer therapy, especially to overcome the breast cancer stem cells mediated chemo- and radioresistances. This review paper discusses several novel theranostic systems and smart nanoparticles, their mechanism of action, and their modifications with time. It explains their relevance and market scope in the current era. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Targeting drugs to tumours using cell membrane-coated nanoparticles

Traditional cancer therapeutics, such as chemotherapies, are often limited by their non-specific nature, causing harm to non-malignant tissues. Over the past several decades, nanomedicine researchers have sought to address this challenge by developing nanoscale platforms capable of more precisely delivering drug payloads. Cell membrane-coated nanoparticles (CNPs) are an emerging class of nanocarriers that have demonstrated considerable promise for biomedical applications. Consisting of a synthetic nanoparticulate core camouflaged by a layer of naturally derived cell membranes, CNPs are adept at operating within complex biological environments; depending on the type of cell membrane utilized, the resulting biomimetic nanoformulation is conferred with several properties typically associated with the source cell, including improved biocompatibility, immune evasion and tumour targeting. In comparison with traditional functionalization approaches, cell membrane coating provides a streamlined method for creating multifunctional and multi-antigenic nanoparticles. In this Review, we discuss the history and development of CNPs as well as how these platforms have been used for cancer therapy. The application of CNPs for drug delivery, phototherapy and immunotherapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CNPs.

A hybrid metal-organic framework nanomedicine-mediated photodynamic therapy and hypoxia-activated cancer chemotherapy

The hypoxic tumor microenvironment and photodynamic therapy (PDT)-aggravated hypoxia compromise the anticancer efficacy of chemotherapy, immunotherapy, and PDT. Thus, sophisticated nanomedicines that can activate their anticancer capability in situ in response to specific stimuli need to be developed. This study aimed to construct a hybrid nanomedicine that activated chemotherapy by inducing hypoxia, which synergized with PDT to promote antitumor outcomes, contrary to the strategies focusing on reversing tumor hypoxia. The hybridization of a porphyrin metal-organic framework (MOF) and gold nanoparticles (AuNPs) enhanced the stability of the hybrid nanomedicine against the phosphate in blood, thereby preventing the premature drug release during blood circulation. The surface modification with polyethylene glycol (PEG) markedly increased the tumor accumulation of the hybrid MOF nanomedicine, which encapsulated a hypoxia-activated prodrug (tirapazamine, TPZ), by enhancing its colloidal stability and pharmacokinetics. The loaded TPZ was rapidly released from the nanomedicine in response to the concentrated intracellular phosphate after cellular uptake, and was then converted into a potent anticancer drug in a hypoxic microenvironment exacerbated by continuous O2 consumption during PDT. In vitro and in vivo experiments demonstrated that the synergistic PDT and hypoxia-activated chemotherapy exhibited enhanced antitumor therapeutic efficiency and superior antimetastatic effect, and effectively ablated the tumor without recurrence. Therefore, the sophisticated nanomedicine reported here, which eliminated cancer cells by inducing a hypoxic tumor microenvironment, showed translational potential in future therapeutic development.

Tumor Antigen Loaded Nanovaccine Induced NIR-Activated Inflammation for Enhanced Antigen Presentation During Immunotherapy of Tumors

Although anticancer vaccines have achieved certain effects in early clinical practice, T cell immunity as the most common responsive pattern of anticancer vaccines is still limited by unsatisfied tumor recognition and inhibition efficiency. As the critical step of T cell immunity, uptake and presentation of specific antigen by antigen-presenting cells (APC) can be activated by inflammation for enhancing the response of T cells to the antigen source. Here, a hybrid nanovaccine named PTh/MnO₂ @M activated with a near-infrared ray (NIR) is prepared by coating an autologous tumor cell membrane on the surface of a polythiophene/MnO₂ composite core. The photoelectrical material polythiophene can produce local microinflammation under NIR radiation and activate specific T cell antitumor immunity by promoting APC maturation and autologous tumor antigens presentation. Moreover, the synthesized nanovaccine PTh/MnO₂ @M is shown to induce a significant antitumor immune response, effectively inhibit the progression of melanoma in mice, and significantly prolong the survival time of mice in vivo. This strategy aims to enhance T-cell immune responses by promoting antigen presentation, leading to effective and specific cancer therapy.

A Novel Instantaneous Self-Assembled Hollow MOF-Derived Nanodrug for Microwave Thermo-Chemotherapy in Triple-Negative Breast Cancer

Hollow materials derived from metal-organic frameworks (MOFs) have emerged in the biomedical field due to their unique properties, and different synthesis methods have been proposed. However, so far, the large-scale use of hollow MOFs is mostly limited by the timeliness of synthesis methods. Herein, we propose a new ultrasonic aerosol flow strategy for the instantaneous synthesis of a Zr-MOF-derived hollow sphere complex (ZC-HSC) in only one step. Through rapid transient heating, the coordination between metal salts and organic ligands occurs along with prompt evaporation of the solvent. The whole process lasts for only about 21 s, compared with several steps that take hours or even days for conventional synthesis methods. Based on the ZC-HSC, we designed a nanodrug with the functions of manipulating the tumor microenvironment, which can reshape the tumor microenvironment by improving tumor hypoxia and inflammatory microenvironment and promoting antiangiogenic therapy. Combined with microwave thermo-chemotherapy, the nanodrugs effectively treat triple-negative breast cancer (the tumor cell survival rate was only 34.76 and 31.05% in normoxic and hypoxic states, respectively, and the tumor inhibition rate reached 87.9% at the animal level), providing a new theoretical basis for the treatment of triple-negative breast cancer. This rapid, one-step, and continuous ultrasonic aerosol flow strategy has bright prospects in the synthesis of MOF-derived hollow materials and promotes the further development of large-scale applications of biological nanomaterials.

Nanoscale MOFs: From synthesis to drug delivery and theranostics applications

Since the first report in 1989, Metal-Organic Frameworks (MOFs) self-assembled from metal ions or clusters, as well as organic linkers, have attracted extensive attention. Due to their flexible composition, large surface areas, modifiable surface properties, and their degradability, there has been an exponential increase in the study of MOFs materials, specifically in drug delivery system areas such as infection, diabetes, pulmonary disease, ocular disease, imaging, tumor therapy, and especially cancer theranostics. In this review, we discuss the trends in MOFs biosafety, from "green" synthesis to applications in drug delivery systems. Firstly, we present the different "green" synthesis approaches used to prepare MOFs materials. Secondly, we detail the methods for the functional coating, either through grafting targeting units, poly(ethylene glycol) (PEG) chains or by using cell membranes. Then, we discuss drug encapsulation strategies, host-guest interactions, as well as drug release mechanisms. Lastly, we report on the drug delivery applications of nanoscale MOFs. In particular, we discuss MOFs-based imaging techniques, including magnetic resonance imaging (MRI), photoacoustic imaging (PAI), positron emission tomography (PET), and fluorescence imaging. MOFs-based cancer therapy methods are also presented, such as photothermal therapy (PTT), photodynamic therapy (PDT), radiotherapy (RT), chemotherapy, and immunotherapy.

Biomineralized hybrid nanodots for tumor therapy via NIR-II fluorescence and photothermal imaging

Chemodynamic therapy (CDT) is an emerging and promising therapeutic strategy that suppresses tumor growth by catalytically converting intracellular hydrogen peroxide (H2O2) into highly-reactive hydroxyl radicals (•OH). However, the inherent substrate of H2O2 is relatively insufficient to achieve desirable CDT efficacy. Therefore, searching for integrated therapeutic methods with synergistic therapeutic modality is especially vital to augment therapeutic outcomes. Herein, we reported nanodot- CuxMnySz @BSA@ICG (denoted as CMS@B@I) and bovine serum albumin (BSA)-based biomineralization CuxMnySz (CMS) loaded with photodynamic agent-indocyanine green (ICG). CMS@B@I converts endogenous hydrogen peroxide (H2O2) into highly active hydroxyl radical (•OH) via Fenton reaction, and effectively produces reactive oxygen species (ROS) after being exposed to 808 nm laser irradiation, attributable to the excellent photodynamic agent-ICG. This results in eliciting a ROS storm. Additionally, CMS@B@I exhibits a superior photothermal effect under NIR-II 1064 nm laser irradiation to enhance tumor CDT efficacy. The NIR-II fluorescence imaging agent of ICG and the excellent photothermal effect of CMS@B@I are highly beneficial to NIR-II fluorescence and infrared thermal imaging, respectively, resulting in tracing the fate of CMS@B@I. This study attempts to design a bimodal imaging-guided and photothermal-enhanced CDT nanoagent for augmenting tumor catalytic therapy.

A Microneedle Patch with Self-Oxygenation and Glutathione Depletion for Repeatable Photodynamic Therapy

Photodynamic therapy (PDT) has attained extensive attention as a noninvasive tumor treatment modality. However, the hypoxia in solid tumors, skin phototoxicity of "always on" photosensitizers (PSs), and abundant supply of glutathione (GSH) in cancer cells severely hampered the clinical applications of PDT. Herein, a self-oxygenation nanoplatform (denoted as CZCH) with GSH depletion ability was encapsulated into the hyaluronic acid microneedle patch (MN-CZCH) to simultaneously improve the biosafety and therapeutic efficacy of PDT. The Cu²⁺-doped porous zeolitic imidazolate framework incorporated with catalase (CAT) is capable of efficiently loading PS 2-(1-hexyloxyethyl)-2-divinylpyropheophorbic-a (HPPH). The CZCH intermingled MN patch (MN-CZCH) could effectively penetrate the stratum corneum, topically transport HPPH to the target tumor site, achieve a long tumor retention time, and enhance the efficacy of PDT via the simultaneously synergistic effect of CAT-catalyzed self-supplying O₂ and Cu²⁺-mediated GSH depletion. Using traceable fluorescence (FL) imaging of the released HPPH from CZCH, the FL imaging-guided repeatable PDT can be achieved for enhanced antitumor efficacy. As a result, the MN-CZCH patch exhibited excellent therapeutic efficacy against melanoma with minimal toxicity, which has promising potential for cancer theranostics.

Rational Modulation of BODIPY Photosensitizers to Design Metal-Organic Framework-Based NIR Nanocomposites for High-Efficiency Photodynamic Therapy in a Hypoxic Environment

Photodynamic therapy (PDT) is a promising noninvasive treatment that has drawn great attention. However, the hypoxic environment in tumors seriously limits the therapeutic effect of oxygen-dependent chemicals and PDT. Herein, a versatile nanocomposite DF-BODIPY@ZIF-8 with oxygen-generating ability was developed based on zeolitic imidazolate framework-8 (ZIF-8) by loading the near-infrared photosensitizer DF-BODIPY to overcome hypoxia-induced drug resistance in cancer therapy. ZIF-8 can catalyze the decomposition of hydrogen peroxide in tumors and increase the dissolved oxygen concentration, resulting in a significant improvement in PDT efficacy. Additionally, we found that enhancing the electronegativity of substituents can effectively reduce the energy level difference (ΔE_st) between the minimum singlet state (S₁) and the lowest triplet state (T₁), leading to the enhancement of the singlet oxygen quantum yield. In vitro experiments suggested that DF-BODIPY@ZIF-8 indeed had a higher singlet oxygen quantum yield and better tumor cell phototoxicity than free DF-BODIPY. In vivo experiments also demonstrated that DF-BODIPY@ZIF-8 could effectively eliminate 4T1 tumors under light irradiation. Thus, we conclude that increasing the electronegativity of substituents and introducing a ZIF-8 material can effectively improve the singlet oxygen quantum yield and overcome the hypoxia limitations for high-efficiency PDT.

Molecularly Targeted Photothermal Ablation of Epidermal Growth Factor Receptor-Expressing Cancer Cells with a Polypyrrole-Iron Oxide-Afatinib Nanocomposite

Simple Summary

In this manuscript, we describe the design and synthesis of a nanocomposite containing afatinib, polypyrrole, and iron oxide (PIA-NC) to molecularly target epidermal growth factor receptor (EGFR)-overexpressing cancer cells for photothermal conversion. In addition to physical and chemical characterization, we also showed that PIA-NC induces selective reactive oxygen species surge and apoptosis in response to sublethal near-infrared light only in EGFR-overexpressing cancer cells, not in EGFR-negative fibroblasts. The work demonstrates the feasibility of photothermal therapy with cellular precision.

Abstract

Near-infrared–photothermal therapy (NIR-PTT) is a potential modality for cancer treatment. Directing photothermal effects specifically to cancer cells may enhance the therapeutic index for the best treatment outcome. While epithelial growth factor receptor (EGFR) is commonly overexpressed/genetically altered in human malignancy, it remains unknown whether targeting EGFR with tyrosine kinase inhibitor (TKI)-conjugated nanoparticles may direct NIR-PTT to cancers with cellular precision. In the present study, we tested this possibility through the fabrication of a polypyrrole–iron oxide–afatinib nanocomposite (PIA-NC). In the PIA-NC, a biocompatible and photothermally conductive polymer (polypyrrole) was conjugated to a TKI (afatinib) that binds to overexpressed wild-type EGFR without overt cytotoxicity. A Fenton catalyst (iron oxide) was further encapsulated in the NC to drive the intracellular ROS surge upon heat activation. Diverse physical and chemical characterization experiments were conducted. Particle internalization, cytotoxicity, ROS production, and apoptosis in EGFR-positive and -negative cell lines were investigated in the presence and absence of NIR. We found that the PIA-NCs were stable with a size of 243 nm and a zeta potential of +35 mV. These PIA-NCs were readily internalized close to the cell membrane by all types of cells used in the study. The Fourier transform infrared spectra showed 3295 cm⁻¹ peaks; substantial O–H stretching was seen, with significant C=C stretching at 1637 cm⁻¹; and a modest appearance of C–O–H bending at 1444 cm⁻¹ confirmed the chemical conjugation of afatinib but not iron oxide to the NC. At a NIR-PTT energy level that has a minimal cytotoxic effect, PIA-NC significantly sensitizes EGFR-overexpressing A549 lung cancer cells to NIR-PTT-induced cytotoxicity at a rate of 70%, but in EGFR-negative 3T3 fibroblasts the rate was 30%. Within 1 min of NIR-PTT, a surge of intracellular ROS was found in PIA-NC-treated A549 cells. This was followed by early induction of cellular apoptosis for 54 ± 0.081% of A549 cells. The number of viable cells was less than a quarter of a percent. Viability levels of A549 cells that had been treated with NIR or PIA were only 50 ± 0.216% and 80 ± 0.216%, respectively. Only 10 ± 0.816% of NIH3T3 cells had undergone necrosis, meaning that 90 ± 0.124% were alive. Viability levels were 65 ± 0.081% and 81 ± 0.2%, respectively, when only NIR and PIA were used. PIA binding was effective against A549 cells but not against NIH3T3 cells. The outcome revealed that higher levels of NC + NIR exposure caused cancer cells to produce more ROS. In summary, our findings proved that a molecularly targeted NC provides an orchestrated platform for cancer cell-specific delivery of NIR-PTT. The geometric proximity design indicates a novel approach to minimizing the off-target biological effects of NIR-PTT. The potential of PIA-NC to be further developed into real-world application warrants further investigation.

Polymeric nanoparticles—Promising carriers for cancer therapy

Polymeric nanoparticles (NPs) play an important role in controlled cancer drug delivery. Anticancer drugs can be conjugated or encapsulated by polymeric nanocarriers, which are known as polymeric nanomedicine. Polymeric nanomedicine has shown its potential in providing sustained release of drugs with reduced cytotoxicity and modified tumor retention, but until now, few delivery systems loading drugs have been able to meet clinical demands, so more efforts are needed. This research reviews the current state of the cancer drug-loading system by exhibiting a series of published articles that highlight the novelty and functions from a variety of different architectures including micelles, liposomes, dendrimers, polymersomes, hydrogels, and metal–organic frameworks. These may contribute to the development of useful polymeric NPs to achieve different therapeutic purposes.

2D Copper(II) Metalated Metal-Organic Framework Nanocomplexes for Dual-enhanced Photodynamic Therapy and Amplified Antitumor Immunity

The immunosuppressive tumor microenvironment (TME) poses tremendous challenges for efficient immunotherapy. Smart nanomedicine is designed to modulate immunosuppressive TMEs based on the combination of dual-enhanced photodynamic therapy (PDT) triggered immunogenic cell death (ICD) and relieved hypoxic microenvironment. Copper(II) metalated metal-organic framework nanosheets (Cu-TCPP(Al)) are the foundation of the nanomedicine, and platinum nanoparticles (Pt NPs) and folate are subsequently introduced onto the Cu-TCPP(Al) surface (Cu-TCPP(Al)-Pt-FA). Upon targeted cellular uptake, intracellular GSH concentration is decreased because of the specific adsorption between GSH and Cu^II; meanwhile, Pt NPs possess catalase-like activity, which can continuously depose intracellular H₂O₂ to O₂ to alleviate the hypoxic TME. The two factors synergistically improve the ROS concentration for dual-enhanced PDT. The highly toxic ROS can correspondingly cause amplified oxidative stress and then trigger the ICD. The ICD process stimulates antigen-presenting cells and activates the systemic antitumor immune response. Furthermore, the relieved hypoxic TME increases the infiltration of cytotoxic T lymphocytes (CTLs) at the tumor site, which can promote the transformation of the immunosuppressive M2 macrophage to immunoactive M1 phenotype. The easily prepared yet versatile nanomedicine possesses an excellent antitumor effect with the cooperation of dual-enhanced PDT and immunotherapy.