Self-adaptive nanoassembly enabling turn-on hypoxia illumination and periphery/center closed-loop tumor eradication

Therapeutic types and advantages of functionalized nanoparticles in inducing ferroptosis in cancer therapy

BACKGROUND

The clinical efficacy of cancer treatment protocols remains unsatisfactory; however, the emergence of ferroptosis-driven therapy strategies has renewed hope for tumor treatment, owing to their remarkable tumor suppression effects. Biologically based small-molecule inducers are used in conventional method to induce ferroptosis. Nevertheless, some molecular drugs have limited solubility, poor ability to target cells, and fast metabolism, which hinder their ability to induce ferroptosis over a prolonged period. Fortunately, further investigations of ferroptosis and the development of nanotechnology have demonstrated that nanoparticles (NPs) are more efficient in inducing ferroptosis than drugs alone, which opens up new perspectives for cancer therapy.

OBJECTIVE

In order to organize a profile of recent advance in NPs for inducing ferroptosis in cancer therapy, and NPs were comprehensively classified in a new light.Materials and methods: We comprehensively searched the databases such as PubMed and Embase. The time limit for searching was from the establishment of the database to 2023.11. All literatures were related to "ferroptosis", "nanoparticles", "nanodelivery systems", "tumors", "cancer".

RESULTS

We summarized and classified the available NPs from a new perspective. The NPs were classified into six categories based on their properties: (1) iron oxide NPs (2) iron - based conversion NPs (3) core-shell structure (4) organic framework (5) silica NPs (6) lipoprotein NPs. According to the therapeutic types of NPs, they can be divided into categories: (1) NPs induced ferroptosis-related immunotherapy (2) NPs loaded with drugs (3) targeted therapy of NPs (4) multidrug resistance therapy (5) gene therapy with NPs (6) energy conversion therapy.

CONCLUSIONS

The insights gained from this review can provide ideas for the development of original NPs and nanodelivery systems, pave the way for related nanomaterials application in clinical cancer therapy, and advance the application and development of nanotechnology in the medical field.

Self-assembled hyaluronic acid nanomicelle for enhanced cascade cancer chemotherapy via self-sensitized ferroptosis

The clinical utility of chemotherapy is often compromised by its limited efficacy and significant side effects. Addressing these concerns, we have developed a self-assembled nanomicelle, namely SANTA FE OXA, which consists of hyaluronic acid (HA) conjugated with ferrocene methanol (FC), oxaliplatin prodrug (OXA(IV)) and ethylene glycol-coupled linoleic acid (EG-LA). Targeted delivery is achieved by HA binding to the CD44 receptors that are overexpressed on tumor cells, facilitating drug uptake. Once internalized, hyaluronidase (HAase) catalyzes the digestion of the SANTA FE OXA, releasing FC and reducing OXA(IV) into an active form. The active oxaliplatin (OXA) induces DNA damage and increases intracellular hydrogen peroxide (H2O2) levels via cascade reactions. Simultaneously, FC disrupts the redox balance within tumor cells, inducing ferroptosis. Both in vivo and in vitro experiments confirmed that SANTA FE OXA inhibited tumor growth by combining cascade chemotherapy and self-sensitized ferroptosis, achieving a tumor inhibition rate of up to 76.61 %. Moreover, this SANTA FE OXA significantly mitigates the systemic toxicity commonly associated with platinum-based chemotherapeutics. Our findings represent a compelling advancement in nanomedicine for enhanced cascade cancer therapy.

Paclitaxel Prodrug Enables Glutathione Depletion to Boost Cancer Treatment

Herein, we constructed a paclitaxel (PTX) prodrug (PA) by conjugating PTX with acrylic acid as a cysteine-depleting agent. The as-synthesized PA can assemble with diacylphosphatidylethanolamine-PEG2000 to form stable nanoparticles (PA NPs). After endocytosis into cells, PA NPs can specifically react with cysteine and trigger release of PTX for chemotherapy. On the other hand, the depletion of cysteine can greatly downregulate the intracellular content of glutathione and lead to oxidative stress outburst-provoking ferroptosis. The released PTX can elicit antitumor immune response by inducing immunogenic cell death, thus promoting dendritic cells maturation and cascaded cytotoxic T lymphocytes activation, which not only produces a robust immunotherapy effect but also synergizes the ferroptosis therapy by inhibiting cysteine transport via the release of interferon-γ in the activated immune system. As a result, PA NPs exhibit favorable in vitro and in vivo antitumor performance with reduced systemic toxicity. Our work highlights the potential of simple molecular design of prodrugs for enhancing the therapeutic efficacy toward malignant cancer.

Modular Prodrug-Engineered Oxygen Nano-Tank With Outstanding Nanoassembly Performance, High Oxygen Loading, and Closed-Loop Tumor Hypoxia Relief

The clinical translation of tumor hypoxia intervention modalities still falls short of expectation, restricted by poor biocompatibility of oxygen-carrying materials, unsatisfactory oxygen loading performance, and abnormally high cellular oxygen consumption-caused insufficient hypoxia relief. Herein, a carrier-free oxygen nano-tank based on modular fluorination prodrug design and co-assembly nanotechnology is elaborately exploited, which is facilely fabricated through the molecular nanoassembly of a fluorinated prodrug (FSSP) of pyropheophorbide a (PPa) and an oxygen consumption inhibitor (atovaquone, ATO). The nano-tank adeptly achieves sufficient oxygen enrichment while simultaneously suppressing oxygen consumption within tumors for complete tumor hypoxia alleviation. Significant, the fluorination module in FSSP not only confers favorable co-assemblage of FSSP and ATO, but also empowers the nanoassembly to readily carry oxygen. As expected, it displays excellent oxygen carrying capacity, favorable pharmacokinetics, on-demand laser-triggerable ATO release, closed-loop tumor hypoxia relief, and significant enhancement to PPa-mediated PDT in vitro and in vivo. This study provides a novel nanotherapeutic paradigm for tumor hypoxia intervention-enhanced cancer therapy.

A metal-coordination stabilized small-molecule nanomedicine with high drug-loading capacity and synergistic photochemotherapy for cancer treatment

Conventional nanomedicines typically employ a significant amount of excipients as carriers for therapeutic delivery, resulting in generally low drug-loading and compromised anti-cancer efficacy. Here, we propose a small-molecule nanomedicine (CMC NP) directly assembled using a chemotherapeutic drug (chlorambucil, CBL) and a phototherapeutic agent (chlorin e6, Ce6), and stabilized by metal coordination. The CMC NP exhibits exceptionally high drug loading (89.21%), robust stability, and smart disassembly in response to glutathione (GSH). Such a straightforward yet multifunctional delivery strategy could be a better alternative to overcome the above shortcomings of conventional nanomedicines while achieving enhanced efficacy. The CMC NP not only directly induces CBL-induced chemotherapy but also elicits synergistic antitumor responses through Ce6-mediated photodynamic and photothermal therapies. Owing to the multifaceted efforts from photodynamic, photothermal and chemo-therapies, the CMC NP exhibits excellent antitumor efficacy with negligible systemic toxicity which is untenable in traditional CBL-induced chemotherapy. Therefore, this study provides a feasible strategy for overcoming existing challenges and presents a potential opportunity to augment the clinical therapeutic effectiveness associated with conventional nanomedicine.

Comparative In Vitro Study between Biocompatible Chitosan-Based Magnetic Nanocapsules and Liposome Formulations with Potential Application in Anti-Inflammatory Therapy

This study describes the comparison between the interaction of a series of peptide-functionalized chitosan-based nanocapsules and liposomes with two cell lines, i.e., mouse macrophages RAW 264.7 and human endothelial cells EA.hy926. Both types of nanocarriers are loaded with magnetic nanoparticles and designed for anti-inflammatory therapy. The choice of these magnetic nanostructures is argued based on their advantages in terms of size, morphology, chemical composition, and the multiple possibilities of modifying their surface. Moreover, active targeting might be ensured by using an external magnetic field. To explore the impact of chitosan-based nanocapsules and liposomes on cell cytophysiology, the cell viability, using the MTT assay, and cell morphology were investigated. The results revealed low to moderate cytotoxicity of free nanocapsules and significant cytotoxicity induced by chitosan-coated liposomes loaded with dexamethasone, confirming its release from the delivery system. Thus, after 48 h of treatment with nanocapsules, the viability of RAW 264.7 cells varied between 88.18% (OCNPM-1I, 3.125 µg/mL) and 76.37% (OCNPM-1, 25 µg/mL). In the same conditions, EA.hy926 cell viability was between 99.91% (OCNPM-3, 3.125 µg/mL) and 75.15% (OCNPM-3, 25 µg/mL) at the highest dose (25 µg/mL), the values being comparable for both cell lines. Referring to the cell reactivity after dexamethasone-loaded liposome application, the lowest viability of RAW 264.7 cells was 41.25% (CLDM5CP-1, 25 µg/mL) and 58.20% (CLDMM2CP-1 1.25 µg/mL) in the endothelial cell line, proving a selective character of action of nanocarriers. The cell morphology test, performed to support and confirm the results obtained by the MTT test, revealed a differentiated response for the two types of nano-carriers. As expected, an intense cytotoxic effect in the case of dexamethasone-loaded liposomes and a lack of cytotoxicity for drug-free nanocapsules were noticed. Therefore, our study demonstrated the biocompatible feature of the studied nanocarriers, which highlights them for future research as potential drug delivery systems for pharmacological applications, including anti-inflammatory therapy.

Small molecule-engineered nanoassembly for lipid peroxidation-amplified photodynamic therapy

Photodynamic therapy (PDT), extensively explored as a non-invasive and spatio-temporal therapeutic modality for cancer treatment, encounters challenges related to the brief half-life and limited diffusion range of singlet oxygen. Lipid peroxides, formed through the oxidation of polyunsaturated fatty acids by singlet oxygen, exhibit prolonged half-life and potent cytotoxicity. Herein, we employed small molecule co-assembly technology to create nanoassemblies of pyropheophorbide a (PPa) and docosahexaenoic acid (DHA) to bolster PDT. DHA, an essential polyunsaturated fatty acid, co-assembled with PPa to generate nanoparticles (PPa@DHA NPs) without the need for additional excipients. To enhance the stability of these nanoassemblies, we introduced 20% DSPE-PEG2k as a stabilizing agent, leading to the formation of PPa@DHA PEG2k NPs. Upon laser irradiation, PPa-produced singlet oxygen swiftly oxidized DHA, resulting in the generation of cytotoxic lipid peroxides. This process significantly augmented the therapeutic efficiency of PDT. Consequently, tumor growth was markedly suppressed, attributed to the sensitizing and amplifying impact of DHA on PDT in a 4T1 tumor-bearing mouse model. In summary, this molecule-engineered nanoassembly introduces an innovative co-delivery approach to enhance PDT with polyunsaturated fatty acids.

Metal organic framework-based variable-size nanoparticles for tumor microenvironment-responsive drug delivery

Nanoparticles (NPs) have been designed for the treatment of tumors increasingly. However, the drawbacks of single-size NPs are still worth noting, as their circulation and metabolism in the blood are negatively correlated with their accumulation at the tumor site. If the size of single-size NPs is too small, it will be quickly cleared in the blood circulation, while, the size is too large, the distribution of NPs in the tumor site will be reduced, and the widespread distribution of NPs throughout the body will cause systemic toxicity. Therefore, a class of variable-size NPs with metal organic frameworks (MOFs) as the main carrier, and size conversion in compliance with the characteristics of the tumor microenvironment (TME), was designed. MOF-based variable-size NPs can simultaneously extend the time of blood circulation and metabolism, then enhance the targeting ability of the tumor site. In this review, MOF NPs are categorized and exemplified from a new perspective of NP size variation; the advantages, mechanisms, and significance of MOF-based variable-size NPs were summarized, and the potential and challenges in delivering anti-tumor drugs and multimodal combination therapy were discussed.

Natural gambogic acid-tuned self-assembly of nanodrugs towards synergistic chemophototherapy against breast cancer

Gambogic acid (GA) as a naturally derived chemotherapeutic agent is of increasing interest for antitumor therapy. However, current research mainly focuses on improving the pharmacological properties to overcome the shortcomings in clinical applications or as a synergistic anticancer agent in combination with chemotherapy and chemophototherapy. Yet, the material properties of GA (e.g., self-assembly) are often neglected. Herein, we validated the self-assembly function of GA and its huge potential as a single-component active carrier for synergistic delivery using pyropheophorbide-a (PPa) as a drug model. The results showed that self-assembled GA drives the formation of nano-GA/PPa mainly through noncovalent interactions such as π-π stacking, hydrophobic interactions, and hydrogen bonding. Additionally, although no significant differences in cytotoxicity were found between the individual in vitro chemotherapy and combined chemophototherapy, the as-prepared nano-GA/PPa exhibits remarkably improved water solubility and multiple favorable therapeutic features, leading to a prominent in vivo photochemotherapy efficiency of 89.3% inhibition rate with reduced hepatotoxicity of GA. This work highlights the potential of self-assembled GA as a drug delivery carrier for synergistic biomedical applications.

Nanotechnology in inflammation: cutting-edge advances in diagnostics, therapeutics and theranostics

Inflammatory dysregulation is intimately associated with the occurrence and progression of many life-threatening diseases. Accurate detection and timely therapeutic intervention on inflammatory dysregulation are crucial for the effective therapy of inflammation-associated diseases. However, the clinical outcomes of inflammation-involved disorders are still unsatisfactory. Therefore, there is an urgent need to develop innovative anti-inflammatory strategies by integrating emerging technological innovations with traditional therapeutics. Biomedical nanotechnology is one of the promising fields that can potentially transform the diagnosis and treatment of inflammation. In this review, we outline recent advances in biomedical nanotechnology for the diagnosis and treatment of inflammation, with special attention paid to nanosensors and nanoprobes for precise diagnosis of inflammation-related diseases, emerging anti-inflammatory nanotherapeutics, as well as nanotheranostics and combined anti-inflammatory applications. Moreover, the prospects and challenges for clinical translation of nanoprobes and anti-inflammatory nanomedicines are highlighted.