Boosting ferroptosis and microtubule inhibition for antitumor therapy via a carrier-free supermolecule nanoreactor

Tannins in cancer prevention and therapy

Tannins are a heterogenous class of polyphenolic natural products with promising cancer chemopreventive and therapeutic potential. Studies undertaken over the last 30 years have demonstrated their capacity to target many cellular pathways and molecules important in the development of cancer. Recently, new mechanisms that might be important in anti-carcinogenic activity, such as inhibition of epithelial-to-mesenchymal transition, reduction of cancer stem cell creation, and modulation of cancer cells metabolism have been described. Along with the mechanisms underlying the anti-cancer activity of tannins, this review focuses on their possible application as chemosensitizers in adjuvant therapy and countering multidrug resistance. Furthermore, characteristic physicochemical properties of some tannins, particularly tannic acid, are useful in the formation of nanovehicles for anticancer drugs or the isolation of circulating cancer cells. These new potential applications of tannins deserve further studies. Well-designed clinical trials, which are scarce, are needed to assess the therapeutic effects of tannins themselves or as adjuvants in cancer treatment. LINKED ARTICLES: This article is part of a themed issue Natural Products and Cancer: From Drug Discovery to Prevention and Therapy. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.10/issuetoc.

Oncogenic KRAS Promotes Ferroptosis in Pancreatic Cancer Through Regulation of the Fosl1-Tfrc Axis

ABSTRACT

Mutant KRAS activation occurs in most of pancreatic ductal adenocarcinoma (PDAC), which induce the sensitivity to ferroptosis of PDAC cells, but the underlying mechanism is still poorly understood. Here, we show how KRAS acts in signaling to activate transcription factor FOSL1, which promotes the expression of the iron uptake receptor TFRC. In PDAC cells, repression of TFRC by KRAS/FOSL1 signaling inhibited intracellular iron levels, thereby restricting the occurrence of ferroptosis. Furthermore, the KRAS/FOSL1/TFRC axis can make the PDAC cells vulnerable to alteration of the iron level in the tumor microenvironment. Our study highlights a pivotal mechanism of PDAC ferroptosis through iron metabolism and supports a new therapeutic strategy for PDAC with superior potential.

WWOX-mediated p53/SAT1 and NRF2/FPN1 axis contribute to toosendanin-induced ferroptosis in hepatocellular carcinoma

Although ferroptosis as an emerging way exhibits tremendous promising in the therapy of hepatocellular carcinoma (HCC), the novel therapeutic agents targeting ferroptosis are still scarce. In our previous study, we found that the natural products toosendanin (TSN) possessed significant anti-proliferative efficacy by regulating WW domain-containing oxidoreductase (WWOX) in HCC. However, there is very limited understanding about TSN-induced ferroptosis, and the role of WWOX in ferroptosis has not been studied. In present study, we investigated the effect and underlying molecular mechanisms of TSN in WWOX-mediated ferroptosis in HCC. We found that TSN induced ferroptosis in HCC cells and its effect was dependent on WWOX. RNA-seq and RT-qPCR assay identified that TSN significantly increased spermidine/spermine N1-acetyltransferase 1 (SAT1) expression while decreased solute carrier family 40 member 1 (SLC40A1) expression, which play vital roles in ferrous ion transport. Further dual-luciferase reporter assay and Co-IP assay revealed that TSN-induced WWOX activation controlled the transcriptional activity of p53 and NF-E2-related factor 2 (NRF2) by regulating their interaction. Meanwhile, IF assay and WB assay confirmed that TSN increased the nuclear distribution of p-WWOX and p-p53 dimers, but impeded the nuclear translocation of NRF2 by inducing its ubiquitination degradation, ultimately regulating the transcription of their downstream target genes. In addition, the results from cell viability assay and the tumor xenograft model verified that co-treatment of TSN, ML385 (NRF2 inhibitor), and MIRA-1 (p53 activator) could effectively inhibit HCC cells growth in the presence of Fer-1 (ferroptosis inhibitor) in vitro and in vivo. Overall, our study contributes to the necessary understanding of the molecular mechanisms of WWOX-mediated ferroptosis regulation, and identifies TSN as a potential therapeutic agent targeting ferroptosis for HCC.

Chemical Design of Magnetic Nanomaterials for Imaging and Ferroptosis-Based Cancer Therapy

Ferroptosis, an iron-dependent form of regulatory cell death, has garnered significant interest as a therapeutic target in cancer treatment due to its distinct characteristics, including lipid peroxide generation and redox imbalance. However, its clinical application in oncology is currently limited by issues such as suboptimal efficacy and potential off-target effects. The advent of nanotechnology has provided a new way for overcoming these challenges through the development of activatable magnetic nanoparticles (MNPs). These innovative MNPs are designed to improve the specificity and efficacy of ferroptosis induction. This Review delves into the chemical and biological principles guiding the design of MNPs for ferroptosis-based cancer therapies and imaging-guided therapies. It discusses the regulatory mechanisms and biological attributes of ferroptosis, the chemical composition of MNPs, their mechanism of action as ferroptosis inducers, and their integration with advanced imaging techniques for therapeutic monitoring. Additionally, we examine the convergence of ferroptosis with other therapeutic strategies, including chemodynamic therapy, photothermal therapy, photodynamic therapy, sonodynamic therapy, and immunotherapy, within the context of nanomedicine strategies utilizing MNPs. This Review highlights the potential of these multifunctional MNPs to surpass the limitations of conventional treatments, envisioning a future of drug-resistance-free, precision diagnostics and ferroptosis-based therapies for treating recalcitrant cancers.

Dietary polyphenols for tumor therapy: bioactivities, nano-therapeutic systems and delivery strategies

Various dietary polyphenols have demonstrated potent anti-tumor properties and are being evaluated as potential adjuncts in cancer treatment. Although several reviews have offered extensive insights into the anti-tumor activities of dietary polyphenols, they frequently lack a detailed discussion on the design of therapeutic protocols and targeted delivery strategies of these compounds, which impedes the translation of their biological activity into clinical practice. This article aims to deliver a comprehensive review of the anti-tumor properties of dietary polyphenols, while also examining the design and implementation of nanotherapy systems based on these compounds. Additionally, given the challenges of low water solubility and stability of dietary polyphenols, this article outlines the current methodologies for the formulation and delivery of nano-preparations to enhance tumor targeting and therapeutic efficacy. This comprehensive review aspires to deepen our understanding of the operational mechanisms of dietary polyphenols and expand their clinical applications, thereby facilitating the development of polyphenol-based dietary supplements and food additives, and promoting the progress of dietary polyphenol-related nanomedicine.

Mitochondria-Targeting Virus-Like Gold Nanoparticles Enhance Chemophototherapeutic Efficacy Against Pancreatic Cancer in a Xenograft Mouse Model

Background

The dense and fibrotic nature of the pancreatic tumor microenvironment significantly contributes to tumor invasion and metastasis. This challenging environment acts as a formidable barrier, hindering effective drug penetration and delivery, which ultimately limits the efficacy of conventional cancer treatments. Gold nanoparticles (AuNPs) have emerged as promising nanocarriers to overcome the extracellular matrix barrier; however, their limited targeting precision, poor delivery efficiency, and insufficient photothermal conversion present challenges.

Methods

We developed triphenyl phosphonium-functionalized high-branch gold nanoparticles, denoted as Dox@TPAu, to enhance drug delivery and targeting capabilities. The targeted penetration, biopharmaceutical and pharmacokinetic properties of Dox@TPAu were characterized, and the synergistic therapeutic effect was evaluated by the BxPC-3 xenograft tumor mouse model.

Results

Dox@TPAu exhibits superior photothermal conversion efficiency (91.0%) alongside a high drug loading efficiency (26%) and effective photo-triggered drug-release potential. This Dox@TPAu drug delivery system adeptly accumulates at tumor sites due to its unique properties, enabling targeted localization within cancer cells and the mitochondria of stromal fibroblasts. This localization disrupts mitochondrial function and transfer-processes crucial for energy production, metabolism, and cell signaling within the tumor microenvironment. Pharmacokinetic analyses revealed an optimal spatiotemporal distribution of Dox@TPAu at the tumor site. This strategic accumulation enables precise disruption of both the physical barrier and cancer cells, enhancing treatment efficacy through near-infrared light-triggered local chemo-photothermal synergistic therapy.

Conclusion

Our findings demonstrate that this innovative strategy effectively leverages the unique properties of mitochondria-targeting, virus-like AuNPs for precise and efficient stromal depletion, presenting a promising approach to enhance the efficacy of pancreatic cancer treatment.

Reprogramming the Tumor Immune Microenvironment Through Activatable Photothermal Therapy and GSH depletion Using Liposomal Gold Nanocages to Potentiate Anti-Metastatic Immunotherapy

Cancer immunotherapy offers significant clinical benefits for patients with advanced or metastatic tumors. However, immunotherapeutic efficacy is often hindered by the tumor microenvironment's high redox levels, leading to variable patient outcomes. Herein, a therapeutic liposomal gold nanocage (MGL) is innovatively developed based on photo-triggered hyperthermia and a releasable strategy by combining a glutathione (GSH) depletion to remodel the tumor immune microenvironment, fostering a more robust anti-tumor immune response. MGL comprises a thermosensitive liposome shell and a gold nanocage core loaded with maleimide. The flexible shell promotes efficient uptake by cancer cells, enabling targeted destruction through photothermal therapy while triggering immunogenic cell death and the maturation of antigen-presenting cells. The photoactivated release of maleimide depletes intracellular GSH, increasing tumor cell sensitivity to oxidative stress and thermal damage. Conversely, GSH reduction also diminishes immunosuppressive cell activity, enhances antigen presentation, and activates T cells. Moreover, photothermal immunotherapy decreases elevated levels of heat shock proteins in tumor cells, further increasing their sensitivity to hyperthermia. In summary, MGL elicited a robust systemic antitumor immune response through GSH depletion, facilitating an effective photothermal immunotherapeutic strategy that reprograms the tumor microenvironment and significantly inhibits primary and metastatic tumors. This approach demonstrates considerable translational potential and clinical applicability.

Systemic delivery of tannic acid-ferric-masked oncolytic adenovirus reprograms tumor microenvironment for improved therapeutic efficacy in glioblastoma

Glioblastoma (GBM) represents the most aggressive primary brain tumor, and urgently requires effective treatments. Oncolytic adenovirus (OA) shows promise as a potential candidate for clinical antitumor therapy, including in the treatment of GBM. Nevertheless, the systemic delivery of OA continues to face challenges, leading to significantly compromised antitumor efficacy. In this study, we developed an innovative approach by encapsulating CXCL11-armed OA with tannic acid and Fe3+ (TA-Fe3+) to realize the systemic delivery of OA. The nanocarrier's ability to protect the OA from elimination by host immune response was evaluated in vitro and in vivo. We evaluated the antitumor effect and safety profile of OA@TA-Fe3+ in a GBM-bearing mice model. OA@TA-Fe3+ effectively safeguarded the virus from host immune clearance and extended its circulation in vivo. After targeting tumor sites, TA-Fe3+ could dissolve and release Fe3+ and OA. Fe3+-induced O2 production from H2O2 relieved the hypoxic state, and promoted OA replication, leading to a remarkable alteration of tumor immune microenvironment and enhancement in antitumor efficacy. Moreover, the systemic delivery of OA@TA-Fe3+ was safe without inflammation or organ damage. Our findings demonstrated the promising potential of systemically delivering the engineered OA for effective oncolytic virotherapy against GBM.

ALKBH5 insufficiency protects against ferroptosis-driven cisplatin-induced renal cytotoxicity

In the clinical setting, cisplatin-induced nephrotoxicity primarily manifests as acute kidney injury (AKI). Recent studies have indicated that ferroptosis, a type of iron-dependent cell death, is closely involved in the cisplatin nephrotoxicity. AlkB homologue 5 (ALKBH5), an N6-methyladenosine (m6A) eraser protein expressed in various tissues, including the kidneys, has been implicated in this process. However, the specific role of ALKBH5 in cisplatin-induced nephrotoxicity remains unknown. Our findings indicated that ALKBH5 was upregulated in cisplatin-induced AKI, and the in vivo study results were consistent with the results of the in vitro study. Additionally, ALKBH5 knockout in transgenic animals was found to mitigate cisplatin-induced renal dysfunction, whereas its knock-in exacerbated the effects. Our study revealed that ALKBH5 controls the traditional ferroptosis metabolic pathway, leading to worsening of AKI in experiments conducted both in vivo and in vitro. The efficacy of pharmacological intervention targeting ALKBH5 in AKI animal models was demonstrated, and ALKBH5-based gene therapy confirmed these findings and displayed renoprotective effects against AKI. In conclusion, this study highlighted the crucial role of ALKBH5 as a key regulator of AKI. Overall, our research demonstrates the significant impact of ALKBH5 in controlling ferroptosis in cisplatin-induced AKI, suggesting that focusing on ALKBH5 could be a promising approach for treating cisplatin-related kidney damage.

Augmented the sensitivity of photothermal-ferroptosis therapy in triple-negative breast cancer through mitochondria-targeted nanoreactor

Ferroptosis primarily relies on reactive oxygen (ROS) production and lipid peroxide (LPO) accumulation, which opens up new opportunities for tumor therapy. However, a standalone ferroptosis process is insufficient in inhibiting tumor progression. Unlike previously reported Fe-based nanomaterials, we have engineered a novel nanoreactor named IR780/Ce@EGCG/APT, which uses metal-polyphenols network (Ce@EGCG) based on rare-earth cerium and epigallocatechin gallate (EGCG) to encapsulate IR780 and modified with the aptamer (AS1411). The intricately designed nanoreactor is specifically taken up by tumor cells, releasing Ce3+, EGCG, and IR780. On the one hand, Ce3+ triggers ROS production via a Fenton-like reaction, inducing ferroptosis in tumor cells. On the other hand, IR780 accumulates in mitochondria and disrupts mitochondrial function upon laser irradiation, leading to tumor cell apoptosis. EGCG serves as a sensitizer, simultaneously enhancing the sensitivity of tumor cells to ferroptosis and photothermal therapy. After a single dose and three times of 808 nm laser irradiation for treatment, it has been observed that the nanoreactor induces dendritic cells (DCs) maturation, facilitates cytotoxic T lymphocyte infiltration, improves immunosuppressive microenvironment, activates the systemic immune system, and generates long-term immune memory.

Gene Expression Regulation and the Signal Transduction of Programmed Cell Death

Cell death is of great significance in maintaining tissue homeostasis and bodily functions. With considerable research coming to the fore, it has been found that programmed cell death presents in multiple modalities in the body, which is not only limited to apoptosis, but also can be divided into autophagy, pyroptosis, ferroptosis, mitotic catastrophe, entosis, netosis, and other ways. Different forms of programmed cell death have disparate or analogous characteristics with each other, and their occurrence is accompanied by multiple signal transduction and the role of a myriad of regulatory factors. In recent years, scholars across the world have carried out considerable in-depth research on programmed cell death, and new forms of cell death are being discovered continually. Concomitantly, the mechanisms of intricate signaling pathways and regulators have been discovered. More critically, cancer cells tend to choose distinct ways to evade cell death, and different tumors adapt to different manners of death. Therefore, targeting the cell death network has been regarded as an effective tumor treatment strategy for a long time. The objective of our paper is to review the signaling pathways and gene regulation in several typical types of programmed cell death and their correlation with cancer.

π-π Stacking Network-Based Supramolecular Peptide Nanoprobe for Visualization of the ICB-Enhanced Ferroptosis Process

The construction of coassembled peptide nanoprobes based on structural adaptation provides an effective template for stable monitoring of the molecular events in physiological and pathological processes. This also greatly expands their applications in biomedicine, such as multimodal combined diagnosis and treatment. However, the insufficient understanding of the physicochemical properties and structural features of different molecules still makes it difficult to construct the coassembled probes with mutually reinforcing functions, leading to unpredictable effects. Here, we showed how to utilize the π-π stacking network on β-sheets formed by PD-L1-targeting peptides to capture small molecules with ferroptosis functions, thus, coassembling them into a visual probe with synergistic effects. Compared with individual components, the coassembled strategy could significantly improve the stability of the nanoprobe, inducing stronger ferroptosis effects and immune checkpoint blocking effects, and track and reflect the process. This study provides new insights into the design of multicomponent collaborative coassembly systems with biological effects.

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.

NIR Absorbing Organic Chromophores Combination with NSAIDs for Remodeling of the Inflammatory Microenvironment to Amplify Tumor Ferroptosis-Photothermal Synergistic Therapy

Photothermal therapy has emerged as a promising approach for cancer treatment, which can cause ferroptosis to enhance immunotherapeutic efficacy. However, excessively generated immunogenicity will induce serious inflammatory response syndrome, resulting in a discounted therapeutic effect. Herein, a kind of NIR absorption small organic chromophore nanoparticles (TTHM NPs) with high photothermal conversion efficiency (68.33%) is developed, which can induce mitochondria dysfunction, generate mitochondrial superoxide, and following ferroptosis. TTHM NPs-based photothermal therapy is combined with Sulfasalazine (SUZ), a kind of nonsteroidal anti-inflammatory drugs, to weaken inflammation and promote ferroptosis through suppressing glutamate/cystine (Glu/Cys) antiporter system Xc- (xCT). Additionally, the combination of SUZ with PTT can induce immunogenic cell death (ICD), followed by promoting the maturation of DCs and the attraction of CD8+ T cell, which will secrete IFN-γ and trigger self-amplified ferroptosis via inhibiting xCT and simulating Acyl-CoA synthetase long-chain family member 4 (ACSL4). Moreover, the in vivo results demonstrate that this combination therapy can suppress the expression of inflammatory factors, enhance dendritic cell activation, facilitate T-cell infiltration, and realize effective thermal elimination of primary tumors and distant tumors. In general, this work provides an excellent example of combined medication and stimulates new thinking about onco-therapy and inflammatory response.

An iron-containing nanomedicine for inducing deep tumor penetration and synergistic ferroptosis in enhanced pancreatic cancer therapy

Pancreatic cancer is an aggressive and challenging malignancy with limited treatment options, largely attributed to the dense tumor stroma and intrinsic drug resistance. Here, we introduce a novel iron-containing nanoparticle formulation termed PTFE, loaded with the ferroptosis inducer Erastin, to overcome these obstacles and enhance pancreatic cancer therapy. The PTFE nanoparticles were prepared through a one-step assembly process, consisting of an Erastin-loaded PLGA core stabilized by a MOF shell formed by coordination between Fe3+ and tannic acid. PTFE demonstrated a unique capability to repolarize tumor-associated macrophages (TAMs) into the M1 phenotype, leading to the regulation of dense tumor stroma by modulating the activation of tumor-associated fibroblasts (TAFs) and reducing collagen deposition. This resulted in enhanced nanoparticle accumulation and deep penetration, as confirmed by in vitro multicellular tumor spheroids and in vivo mesenchymal-rich subcutaneous pancreatic tumor models. Moreover, PTFE effectively combated tumor resistance by synergistically employing the Fe3+-induced Fenton reaction and Erastin-induced ferroptosis, thereby disrupting the redox balance. As a result, significant tumor growth inhibition was achieved in mice-bearing tumor model. Comprehensive safety evaluations demonstrated PTFE's favorable biocompatibility, highlighting its potential as a promising therapeutic platform to effectively address the formidable challenges in pancreatic cancer treatment.

Cell cycle associated protein 1 associates with immune infiltration and ferroptosis in gastrointestinal cancer

Background

Cell Cycle-Associated Protein 1 (CAPRIN1) play an important role in cell proliferation, oxidative stress, and inflammatory response. Nonetheless, its role in tumor immunity and ferroptosis is largely unknown in gastrointestinal cancer patients.

Methods

Through comprehensive bioinformatics, we investigate CAPRIN1 expression patterns and its role in diagnosis, functional signaling pathways, tumor immune infiltration and ferroptosis of different gastrointestinal cancer subtypes. Besides, immunohistochemistry (IHC) and immune blot were used to validate our esophagus cancer clinical data. The ferroptotic features of CAPRIN1 in vitro were assessed through knockdown assays in esophagus cancer cells.

Results

CAPRIN1 expression was significantly upregulated, correlated with poor prognosis, and served as an independent risk factor for most gastrointestinal cancer. Moreover, CAPRIN1 overexpression positively correlated with gene markers of most infiltrating immune cells, and immune checkpoints. CAPRIN1 knockdown significantly decreased the protein level of major histocompatibility complex class I molecules. We also identified a link between CAPRIN1 and ferroptosis-related genes in gastrointestinal cancer. Knockdown of CAPRIN1 significantly increased the production of lipid reactive oxygen species and malondialdehyde. Inhibition of CAPRIN1 expression promoted ferroptotic cell death induced by RAS-selective lethal 3 and erastin in human esophagus cancer cells.

Conclusion

Collectively, our results demonstrate that CAPRIN1 is aberrantly expressed in gastrointestinal cancer, is associated with poor prognosis, and could potentially influence immune infiltration and ferroptosis.

Nanoreactor based on single-atom nanoenzymes promotes ferroptosis for cancer immunotherapy

Immunotherapy is a promising mainstream approach in anti-tumor therapy. It boasts advantages such as durable responses and lower side effects. However, there are still some limitations to be addressed. Current cancer immunotherapy has shown low response rates due to inadequate immunogenicity of certain tumor cells. To address these challenges, an acid-specific nanoreactor was developed, designed to induce immunogenicity by triggering ferroptosis in tumor cells. The nanoreactor integrates glucose oxidase (GOx) with a single-atom nanoenzyme (SAE), which exhibits high peroxidase (POD)-like activity in the acidic tumor microenvironment (TME). This specific acid-sensitivity transforms endogenous hydrogen peroxide (H2O2) into cytotoxic hydroxyl radicals (•OH). GOx enhances the POD-like SAE activity in the nanoreactor by metabolizing glucose in tumor cells, producing gluconic acid and H2O2. This nanoreactor induces high levels of oxidative stress within tumor cells through the synergistic action of SAE and GOx, leading to depletion of GSH and subsequently triggering ferroptosis. The resulting nanoreactor-induced ferroptosis leads to immunogenic cell death (ICD) and significantly recruits T lymphocyte infiltration in tumor tissues. This study was designed with the concept of triggering ferroptosis-dependent ICD mechanism in bladder cancer cells, and developed an acid-specific nanoreactor to enhance the immunotherapy efficacy for bladder cancer, which introduces a novel approach for immunotherapy of bladder cancer.

Iron-Based Nanovehicle Delivering Fin56 for Hyperthermia-Boosted Ferroptosis Therapy Against Osteosarcoma

Background

Although systemic chemotherapy is a standard approach for osteosarcoma (OS) treatment, its efficacy is limited by the inherent or acquired resistance to apoptosis of tumor cells. Ferroptosis is considered as an effective strategy capable of stimulating alternative pathways of cancer cell demise. The purpose of this study is to develop a novel strategy boosting ferroptotic cascade for synergistic cancer therapy.

Methods and Results

A novel nanovehicle composed of arginine-glycine-aspartate (RGD) modified mesoporous silica-coated iron oxide loading Fin56 was rationally prepared (FSR-Fin56). With the RGD-mediated targeting affinity, FSR-Fin56 could achieve selective accumulation and accurate delivery of cargos into cancer cells. Upon exposure to NIR light, the nanovehicle could generate localized hyperthermia and disintegrate to liberate the therapeutic payload. The released Fin56 triggered the degradation of GPX4, while Fe3+ depleted the intracellular GSH pool, producing Fe2+ as a Fenton agent. The local rise in temperature, in conjunction with Fe2+-mediated Fenton reaction, led to a rapid and significant accumulation of ROS, culminating in LPOs and ferroptotic death. The outstanding therapeutic efficacy and safety of the nanovehicle were validated both in vitro and in vivo.

Conclusion

The Fin56-loaded FSR nanovehicle could effectively disturb the redox balance in cancer cells. Coupled with NIR laser irradiation, the cooperative CDT and PTT achieved a boosted ferroptosis-inducing therapy. Taken together, this study offers a compelling strategy for cancer treatment, particularly for ferroptosis-sensitive tumors like osteosarcoma.

Hydralazine represses Fpn ubiquitination to rescue injured neurons via competitive binding to UBA52

A major impedance to neuronal regeneration after peripheral nerve injury (PNI) is the activation of various programmed cell death mechanisms in the dorsal root ganglion. Ferroptosis is a form of programmed cell death distinguished by imbalance in iron and thiol metabolism, leading to lethal lipid peroxidation. However, the molecular mechanisms of ferroptosis in the context of PNI and nerve regeneration remain unclear. Ferroportin (Fpn), the only known mammalian nonheme iron export protein, plays a pivotal part in inhibiting ferroptosis by maintaining intracellular iron homeostasis. Here, we explored in vitro and in vivo the involvement of Fpn in neuronal ferroptosis. We first delineated that reactive oxygen species at the injury site induces neuronal ferroptosis by increasing intracellular iron via accelerated UBA52-driven ubiquitination and degradation of Fpn, and stimulation of lipid peroxidation. Early administration of the potent arterial vasodilator, hydralazine (HYD), decreases the ubiquitination of Fpn after PNI by binding to UBA52, leading to suppression of neuronal cell death and significant acceleration of axon regeneration and motor function recovery. HYD targeting of ferroptosis is a promising strategy for clinical management of PNI.

Autophagy/ferroptosis in colorectal cancer: Carcinogenic view and nanoparticle-mediated cell death regulation

The cell death mechanisms have a long history of being evaluated in diseases and pathological events. The ability of triggering cell death is considered to be a promising strategy in cancer therapy, but some mechanisms have dual functions in cancer, requiring more elucidation of underlying factors. Colorectal cancer (CRC) is a disease and malignant condition of colon and rectal that causes high mortality and morbidity. The autophagy targeting in CRC is therapeutic importance and this cell death mechanism can interact with apoptosis in inhibiting or increasing apoptosis. Autophagy has interaction with ferroptosis as another cell death pathway in CRC and can accelerate ferroptosis in suppressing growth and invasion. The dysregulation of autophagy affects the drug resistance in CRC and pro-survival autophagy can induce drug resistance. Therefore, inhibition of protective autophagy enhances chemosensitivity in CRC cells. Moreover, autophagy displays interaction with metastasis and EMT as a potent regulator of invasion in CRC cells. The same is true for ferroptosis, but the difference is that function of ferroptosis is determined and it can reduce viability. The lack of ferroptosis can cause development of chemoresistance in CRC cells and this cell death mechanism is regulated by various pathways and mechanisms that autophagy is among them. Therefore, current review paper provides a state-of-art analysis of autophagy, ferroptosis and their crosstalk in CRC. The nanoparticle-mediated regulation of cell death mechanisms in CRC causes changes in progression. The stimulation of ferroptosis and control of autophagy (induction or inhibition) by nanoparticles can impair CRC progression. The engineering part of nanoparticle synthesis to control autophagy and ferroptosis in CRC still requires more attention.

Polyphenol-Based Nanosystems for Next-Generation Cancer Therapy: Multifunctionality, Design, and Challenges

With the continuous updating of cancer treatment methods and the rapid development of precision medicine in recent years, there are higher demands for advanced and versatile drug delivery systems. Scientists are committed to create greener and more effective nanomedicines where the carrier is no longer limited to a single function of drug delivery. Polyphenols, which can act as both active ingredients and fundamental building blocks, are being explored as potential multifunctional carriers that are efficient and safe for design purposes. Due to their intrinsic anticancer activity, phenolic compounds have shown surprising expressiveness in ablation of tumor cells, overcoming cancer multidrug resistance (MDR), and enhancing immunotherapeutic efficacy. This review provides an overview of recent advances in the design, synthesis, and application of versatile polyphenol-based nanosystems for cancer therapy in various modes. Moreover, the merits of polyphenols and the challenges for their clinical translation are also discussed, and it is pointed out that the novel polyphenol delivery system requires further optimization and validation.

Lipid-Polymer Hybrid Nanoparticles with Both PD-L1 Knockdown and Mild Photothermal Effect for Tumor Photothermal Immunotherapy

In developing countries, the incidence of colorectal cancer (CRC) is on the rise. The combination of programmed cell death ligand-1 (PD-L1) siRNA (siPD-L1) and mild photothermal therapy (PTT) is a promising strategy for CRC treatment. In this study, dopamine-modified polyethylenimine (PEI) was prepared to fabricate an IR780 and siPD-L1 codelivery lipid-polymer hybrid nanoparticle (lip@PSD-siP) for the photothermal immunotherapy of CRC. The modification of dopamine can significantly reduce the cytotoxicity of PEI. lip@PSD-siP can be effectively taken up by CT26 cells and successfully escaped from lysosomes after entering the cells for 4 h. After CT26 cells were transfected with lip@PSD-siP, the PD-L1 positive cell rate decreased by 82.4%, and its PD-L1 knockdown effect was significantly stronger than the positive control Lipo3000-siP. In vivo studies showed that lip@PSD-siP-mediated mild PTT and efficient PD-L1 knockdown exhibited primary and distal tumor inhibition, metastasis delay, and rechallenged tumor inhibition. The treatment with lip@PSD-siP significantly promoted the maturation of dendritic cells in lymph nodes. The amount of T cell infiltration in the tumor tissues increased significantly, and the frequency of CD8+ T cells and CD4+ T cells was significantly higher than that of other groups. The percentage of immunosuppressive regulatory cells (Tregs) in the tumor tissue on the treatment side decreased by 88% compared to the PBS group, and the proportion of CD8+CD69+ T cells in the distal tumor tissue was 2.8 times that of the PBS group. The memory T cells of mice in the long-term antitumor model were analyzed. The results showed that after treatment with lip@PSD-siP, the frequency of effector memory T cells (Tem cells) significantly increased, suggesting the formation of immune memory.

Advancements in pH-responsive nanocarriers: enhancing drug delivery for tumor therapy

INTRODUCTION

Tumors pose a significant global economic and health burden, with conventional cancer treatments lacking tumor specificity, leading to limited efficiency and undesirable side effects. Targeted tumor therapy is imminent. Tumor cells produce lactate and hydrogen ions (H+) by Warburg effect, forming an acidic tumor microenvironment (TME), which can be employed to design targeted tumor therapy. Recently, progress in nanotechnology has led to the development of pH-responsive nanocarriers, which have gathered significant attention. Under acidic tumor conditions, they exhibit targeted accumulation within tumor sites and controlled release profiles of therapeutic reagents, enabling precise tumor therapy.

AREAS COVERED

This review comprehensively summarize the principles underlying pH-responsive features, discussing various types of pH-responsive nanocarriers, their advantages, and limitations. Innovative therapeutic drugs are also examined, followed by an exploration of recent advancements in applying various pH-responsive nanocarriers as delivery systems for enhanced tumor therapy.

EXPERT OPINIONS

pH-responsive nanocarriers have garnered significant attention for their capability to achieve targeted accumulation of therapeutic agents at tumor sites and controlled drug delivery profiles, ultimately increasing the efficiency of tumor eradication. It is anticipated that the employment of pH-responsive nanocarriers will elevate the effectiveness and safety of tumor therapy, contributing to improved overall outcomes.