The tumor EPR effect for cancer drug delivery: Current status, limitations, and alternatives

Targeting lipid metabolism via nanomedicine: A prospective strategy for cancer therapy

Lipid metabolism has been increasingly recognized to play an influencing role in tumor initiation, progression, metastasis, and therapeutic drug resistance. Targeting lipid metabolic reprogramming represents a promising therapeutic strategy. Despite their structural complexity and poor targeting efficacy, lipid-metabolizing drugs, either used alone or in combination with chemotherapeutic agents, have been employed in clinical practice. The advent of nanotechnology offers new approaches to enhancing therapeutic effects, includingthe targeted delivery and integration of lipid metabolic reprogramming with chemotherapy, photodynamic therapy (PDT), and immunotherapy. The integrated nanoformulation, nanomedicine, could significantly advance the field of lipid metabolism therapy. In this review, we will briefly introduce the concept of cancer lipid metabolism reprogramming, then elaborate the latest advances in engineered nanomedicine for targeting lipid metabolism during cancer treatment, and finally provide our insights into future perspectives of nanomedicine for interference with lipid metabolism in the tumor microenvironment.

Regulating tumor cells to awaken T cell antitumor function and enhance melanoma immunotherapy

Tumor cells transmit various immunosuppressive signals and induce a dysfunctional state in T cells, which essentially leads to immune escape and tumor progression. However, developing effective strategies to counteract the domestication of T cells by tumor cells remains a challenge. Here, we prepared pH-responsive lipid nanoparticles (NL/PLDs) co-loaded with PCSK9 shRNA, lonidamine (LND), and low-dose doxorubicin (DOX). NL/PLDs can awaken domesticated T cells function by sending pro-activation, pro-recognition, and pro-killing signals by increasing tumor immunogenicity, increasing the expression of major histocompatibility complex I (MHC-I) on tumor cells, and alleviating the suppression effect of tumor-secreted lactic acid (LA) on the T cell effector function, respectively. In melanoma-bearing mice, NL/PLDs effectively relieved tumor immunosuppressive microenvironment (TIME) and enhanced the antitumor immunity mediated by CD8+ T cells. Furthermore, when combined with aPD-1, NL/PLDs demonstrated strong antitumor effects and increased immunotherapeutic efficacy. This regulatory strategy provides new insights for enhancing immunotherapy by regulating tumor immunosuppressive signals and shows significant potential for clinical tumor treatment.

Targeting tumor microenvironment with RGD-functionalized nanoparticles for precision cancer therapy

The need for precision therapies arises from the complexities associated with high-risk types of cancer, due to their aggressiveness and resistance to treatment. These diseases represent a global issue that requires transversal strategies involving cooperation among oncology specialists and experts from related fields, including nanomedicine. Nanoparticle-mediated active targeting of tumors has proven to be a revolutionary approach to address the most challenging neoplasms by overcoming the poor permeation at tumor site of untargeted, and nowadays questioned, strategies that rely solely on Enhanced Permeability and Retention (EPR) effects. The decoration of nanoparticles with Arg-Gly-Asp (RGD) peptides, which selectively target integrins on the cell membrane, marks a turning point in tumor microenvironment (TME) targeted strategies, enabling precision and efficiency in the delivery of chemotherapeutics. This review delves into the intricacies of the TME's features and targetable components (i.e. integrins), and the development of RGDs for nanoparticles' functionalization for active TME targeting. It provides a translational perspective on the integration of RGD-functionalized nanoparticles in oncology, highlighting their potential to overcome current therapeutic challenges, particularly in precision medicine. The current landscape of targeted nanomedicines in the clinic, and the development of RGD-nanomedicine for pediatric cancers are also discussed.

Pulmonary delivery of dual-targeted nanoparticles improves tumor accumulation and cancer cell targeting by restricting macrophage interception in orthotopic lung tumors

Despite the recognized potential of inhaled nanomedicines to enhance and sustain local drug concentrations for lung cancer treatment, the influence of macrophage uptake on targeted nanoparticle delivery to and within tumors remains unclear. Here, we developed three ligand-coated nanoparticles for pulmonary delivery in lung cancer therapy: phenylboronic acid-modified nanoparticles (PBA-NPs), PBA combined with folic acid (FA-PBA-NPs), and PBA with mannose (MAN-PBA-NPs). In vitro, MAN-PBA-NPs were preferentially internalized by macrophages, whereas FA-PBA-NPs exhibited superior uptake by cancer cells compared to macrophages. Following intratracheal instillation into mice with orthotopic Lewis lung carcinoma tumors, all three nanoparticles showed similar lung retention. However, MAN-PBA-NPs were more prone to interception by lung macrophages, which limited their accumulation in tumor tissues. In contrast, both PBA-NPs and FA-PBA-NPs achieved comparable high tumor accumulation (∼11.3% of the dose). Furthermore, FA-PBA-NPs were internalized by ∼30% of cancer cells, significantly more than the 10-18% seen with PBA-NPs or MAN-PBA-NPs. Additionally, FA-PBA-NPs loaded with icaritin effectively inhibited the Wnt/β-catenin pathway, resulting in superior anti-tumor efficacy through targeted cancer cell delivery. Overall, FA-PBA-NPs demonstrated advantageous competitive uptake kinetics by cancer cells compared to macrophages, enhancing tumor targeting and therapeutic outcomes.

Self-assembled HO-1i-Pt(IV) nanomedicine targeting p38/MAPK and MDR pathways for cancer chemo-immunotherapy

Platinum(II)-based antitumor drugs are widely used in clinics but limited by severe side effects and resistance. Multi-target Platinum(IV) complexes are emerging as ideal alternatives. Heme oxygenase-1 (HO-1) works as a rate-limiting step in heme degradation and is overexpressed in malignant tumors. Herein, HO-1i-based Platinum(IV) prodrugs are prepared and candidate complex 15 is further developed into self-assembled nanoparticles (15-NPs). 15 and 15-NPs significantly increase cytotoxicity, particularly in HepG2 (74.77- and 96.14-fold increases) and A549cisR (38.6- and 47.24-fold increases), while reducing toxicity towards normal cells compared to cisplatin. In vitro experiments show 15 and 15-NPs activated multiple pathways, including p38/MAPK- and MDR-related proteins, achieving multi-target synergistic chemosensitization and anti-resistance, further verified by RNA-sequencing analysis. In vivo tests demonstrate that 15 and 15-NPs efficiently inhibit tumor growth and systemic toxicity, especially 15-NPs with optimal tumor-inhibition rate and survival (80% and 100%), superior to cisplatin (40% and 50%), attributing to its extra endocytosis, EPR effect, and precisely tumor-targeted release besides the advantage of a free HO-1i-Pt(IV) prodrug. Additionally, 15 and 15-NPs distinctly regulate T-cell and macrophage functions, thereby exhibiting a chemoimmuno-combined action. This study highlights that multi-functional Platinum(IV) prodrug target-delivered to tumors via carrier-free nanoparticles may represent an effective modality for improving cancer therapy.

Hypoxia-responsive micelles deprive cofactor of stearoyl-CoA desaturase-1 and sensitize ferroptotic ovarian cancer therapy

Ferroptosis has been recognized as a promising therapeutic strategy for cancer due to its unique mechanism of action. However, the upregulation of stearoyl-CoA desaturase 1 (SCD1) in ovarian cancer leads to resistance to ferroptotic therapy. Zinc ion (Zn2+) serves as the cofactor of SCD1. It was hypothesized that selective deprivation of Zn2+ from SCD1 could sensitize ferroptotic ovarian cancer therapy. Here, we report a hypoxia-responsive polymer micelle for enhanced ferroptosis of ovarian cancer cells. A SCD1 inhibitor, PluriSIn 1 (Plu), and a ferroptosis inducer, Auranofin (Aur), were co-encapsulated in nitroimidazole-bearing micelles. Under the hypoxic tumor microenvironment, the conversion of nitroimidazole to aminoimidazole triggered the cargo release and induced the depletion of antioxidant molecules (e.g., glutathione, thioredoxin, and NADPH). Meanwhile, because of the strong coordination between aminoimidazole and Zn2+ compared to that of histidine and Zn2+, such conversion can deprive the metal cofactor of SCD1, hence sensitizing the action of Plu and Aur. The proof-of-concept was demonstrated in cell and animal models with minimal systemic toxicity. The current work integrates ferroptosis induction with SCD1 inhibition in a hypoxia-responsive vehicle, offering a promising strategy for addressing the ferroptosis resistance and opening novel avenues for managing the difficult-to-treat ovarian cancer.

The second phase of tumor invasion driven by immune cells: A study on doxorubicin-loaded PLG nanoparticles

Poly(lactide-co-glycolide) (PLG) nanoparticles loaded with doxorubicin have reached phase-I clinical trials for treating advanced solid tumors. This study explores cell hitchhiking, where nanoparticles associate with blood cells and investigates the impact on pharmacokinetics and tumor migration. Previous findings highlighted the early post-injection phase dominated by nonspecific nanoparticle-cell interactions and burst release. In contrast, this study examines the subsequent phase of tumor invasion, emphasizing the role of immune cells, mostly neutrophils, in redistributing the carrier to the tumor site via blood cell hitchhiking. We provide a detailed investigation of nanoparticle extravasation kinetics and mechanisms, showing qualitative and quantitative evidence of increased nanoparticle association with immune cells over time. By 30 min post-injection, approximately 15 % of monocytes and 15-19 % of neutrophils tested positive for nanoparticles, with significant differences observed between ex vivo and in vivo experiments, and between healthy and tumor-bearing animals. This study underscores the ambiguous role of immune cell-mediated tumor targeting. While the total accumulation of the carrier rises, this fraction is partially trapped in immune cells without any chance to escape.

Conversion therapy strategy: A novel GPC3-targeted multimodal organic phototheranostics platform for mid-late-stage hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is typically diagnosed at intermediate to advanced stage, making surgical treatment unfeasible. Conversion therapy aims to reduce tumor stage, improve hepatic resection feasibility, and lower recurrence rates. Since traditional therapies are often accompanied by uncertainty of efficacy, there is an urgent need to explore new treatment strategies. Near-infrared phototheranostics technology provides a new way for HCC diagnosis and treatment by its excellent optical properties. However, complex preparation and poor biocompatibility of phototheranostics probes limit clinical application. In this study, we developed a fluorescence/magnetic resonance dual-modality imaging (FLI/MRI) as well as photothermal/photodynamic therapy (PTT/PDT) GPC3-targeted multifunctional phototheranostics probe, IR820-GPC3-Gd NPs (IGD NPs), to improve the efficiency of conversion therapy for HCC. The IGD NPs were simply prepared with the IR820 as the core. Conjugating the HCC-specific targeting molecule GPC3 peptide and the MRI agent DOTA-Gd through click chemistry. IGD NPs target HCC cells through GPC3, releasing heat and reactive oxygen species (ROS) under noninvasive 808 nm laser irradiation to reduce tumor size and achieve downstaging. High-sensitivity FLI/MRI precisely delineates tumor boundaries, providing real-time surgical navigation and prognosis assessment. This novel probe offers a feasible and effective treatment option for advanced HCC.

Comparison of the accumulation manner of a macromolecular drug between two mouse tumour models: study with magnetic resonance imaging and the model macromolecular drug, gadolinium-conjugated dextran

A knowledge of the difference of spatio-temporal behaviour of nanomedicine in different type of tumour models is important to develop well-targeted nanomedicine for tumour. In this study, intratumoral accumulation of the model nanomedicine, gadolinium-conjugated dextran (Gd-Dex), was examined with magnetic resonance imaging in two tumour models; mouse sarcoma S180 and radiation-induced mouse fibrosarcoma RIF-1. From time-course of the distribution images, the plasma-to-tumour interstitial tissue transfer constant (Ktrans) and fractional plasma volume (Vp) were calculated and mapped. Gd-Dex preferentially distributed to the marginal region of S180 tumours immediately after its injection, and then started to accumulate in some parts of the central region. Ktrans and Vp values were large in the marginal region, while only Ktrans was large in some parts of the central region. In contrast, the distribution of Gd-Dex in RIF-1 tumours was fairly homogeneous, and may have resulted from the homogeneous distributions of Ktrans and Vp. The amounts of Gd-Dex that accumulated in entire tumours in both tumour models correlated with the volume of tumours; however, accumulation in large S180 tumours deviated from the correlation in the early phase. The differences in the manner and pharmacokinetics of nanomedicine among tumour models may affect the accumulation of the medicine.

Exploiting novel placental homing peptides for targeted drug delivery in breast cancer

More effective drug formulations are needed to increase the selectivity and efficacy of available chemotherapeutics. We have previously shown that nanoparticles decorated with the tumour homing peptide CGKRK can selectively deliver payloads to the placenta. In this study, we investigated whether two novel placental homing peptides NKGLRNK (NKG) and RSGVAKS (RSG) can be utilized to selectively deliver doxorubicin (DOX) to breast cancer cells. Fluorescence microscopy and flow cytometry showed that NKG and RSG bind to and accumulate in MDA-MB-231 and MCF-7 cells in a time-dependent manner, to a similar extent as CGKRK, but accumulate in healthy MCF-10A cells to a much lesser degree. NKG- and RSG-decorated liposomes facilitated equivalent delivery of DOX to MDA-MB-231 and MCF-7 cells, with a comparable efficacy to CGKRK-decorated liposomes. These findings suggest that NKG and RSG represent novel breast tumour-binding sequences that could be utilized to develop more efficacious targeted breast cancer therapies.

Tumor-Targeted Catalytic Immunotherapy

Cancer immunotherapy holds significant promise for improving cancer treatment efficacy; however, the low response rate remains a considerable challenge. To overcome this limitation, advanced catalytic materials offer potential in augmenting catalytic immunotherapy by modulating the immunosuppressive tumor microenvironment (TME) through precise biochemical reactions. Achieving optimal targeting precision and therapeutic efficacy necessitates a thorough understanding of the properties and underlying mechanisms of tumor-targeted catalytic materials. This review provides a comprehensive and systematic overview of recent advancements in tumor-targeted catalytic materials and their critical role in enhancing catalytic immunotherapy. It highlights the types of catalytic reactions, the construction strategies of catalytic materials, and their fundamental mechanisms for tumor targeting, including passive, bioactive, stimuli-responsive, and biomimetic targeting approaches. Furthermore, this review outlines various tumor-specific targeting strategies, encompassing tumor tissue, tumor cell, exogenous stimuli-responsive, TME-responsive, and cellular TME targeting strategies. Finally, the discussion addresses the challenges and future perspectives for transitioning catalytic materials into clinical applications, offering insights that pave the way for next-generation cancer therapies and provide substantial benefits to patients in clinical settings.

Recent Advances in Nanoenzymes Based Therapies for Glioblastoma: Overcoming Barriers and Enhancing Targeted Treatment

Glioblastoma multiforme (GBM) is a highly aggressive and malignant brain tumor originating from glial cells, characterized by high recurrence rates and poor patient prognosis. The heterogeneity and complex biology of GBM, coupled with the protective nature of the blood-brain barrier (BBB), significantly limit the efficacy of traditional therapies. The rapid development of nanoenzyme technology presents a promising therapeutic paradigm for the rational and targeted treatment of GBM. In this review, the underlying mechanisms of GBM pathogenesis are comprehensively discussed, emphasizing the impact of the BBB on treatment strategies. Recent advances in nanoenzyme-based approaches for GBM therapy are explored, highlighting how these nanoenzymes enhance various treatment modalities through their multifunctional capabilities and potential for precise drug delivery. Finally, the challenges and therapeutic prospects of translating nanoenzymes from laboratory research to clinical application, including issues of stability, targeting efficiency, safety, and regulatory hurdles are critically analyzed. By providing a thorough understanding of both the opportunities and obstacles associated with nanoenzyme-based therapies, future research directions are aimed to be informed and contribute to the development of more effective treatments for GBM.

Nanomaterial-enabled metabolic reprogramming strategies for boosting antitumor immunity

Immunotherapy has become a crucial strategy in cancer treatment, but its effectiveness is often constrained. Most cancer immunotherapies focus on stimulating T-cell-mediated immunity by driving the cancer-immunity cycle, which includes tumor antigen release, antigen presentation, T cell activation, infiltration, and tumor cell killing. However, metabolism reprogramming in the tumor microenvironment (TME) supports the viability of cancer cells and inhibits the function of immune cells within this cycle, presenting clinical challenges. The distinct metabolic needs of tumor cells and immune cells require precise and selective metabolic interventions to maximize therapeutic outcomes while minimizing adverse effects. Recent advances in nanotherapeutics offer a promising approach to target tumor metabolism reprogramming and enhance the cancer-immunity cycle through tailored metabolic modulation. In this review, we explore cutting-edge nanomaterial strategies for modulating tumor metabolism to improve therapeutic outcomes. We review the design principles of nanoplatforms for immunometabolic modulation, key metabolic pathways and their regulation, recent advances in targeting these pathways for the cancer-immunity cycle enhancement, and future prospects for next-generation metabolic nanomodulators in cancer immunotherapy. We expect that emerging immunometabolic modulatory nanotechnology will establish a new frontier in cancer immunotherapy in the near future.

Advances in Drug Targeting, Drug Delivery, and Nanotechnology Applications: Therapeutic Significance in Cancer Treatment

In the 21st century, thanks to advances in biotechnology and developing pharmaceutical technology, significant progress is being made in effective drug design. Drug targeting aims to ensure that the drug acts only in the pathological area; it is defined as the ability to accumulate selectively and quantitatively in the target tissue or organ, regardless of the chemical structure of the active drug substance and the method of administration. With drug targeting, conventional, biotechnological and gene-derived drugs target the body's organs, tissues, and cells that can be selectively transported to specific regions. These systems serve as drug carriers and regulate the timing of release. Despite having many advantageous features, these systems have limitations in thoroughly treating complex diseases such as cancer. Therefore, combining these systems with nanoparticle technologies is imperative to treat cancer at both local and systemic levels effectively. The nanocarrier-based drug delivery method involves encapsulating target-specific drug molecules into polymeric or vesicular systems. Various drug delivery systems (DDS) were investigated and discussed in this review article. The first part discussed active and passive delivery systems, hydrogels, thermoplastics, microdevices and transdermal-based drug delivery systems. The second part discussed drug carrier systems in nanobiotechnology (carbon nanotubes, nanoparticles, coated, pegylated, solid lipid nanoparticles and smart polymeric nanogels). In the third part, drug targeting advantages were discussed, and finally, market research of commercial drugs used in cancer nanotechnological approaches was included.

A water-soluble aggregation-induced emission luminogen for NIR-I/NIR-II fluorescence imaging of breast cancer bone metastases

Advanced breast cancer is prone to bone metastasis, which is the most common bone metastatic tumor. Current clinical methods for diagnosing breast cancer bone metastases rely on serological markers, computed tomography and magnetic resonance imaging. However, these technologies cannot meet patients' needs due to the delayed screening, complex procedures and expensive equipment. Optical imaging currently exhibits inexhaustible and vigorous vitality in the field of diagnosis thanks to its advantages of simplicity, good controllability and high resolution. Nevertheless, the development of prominent chromophores for the diagnosis of breast cancer bone metastases is an appealing yet significantly challenging task. In this contribution, we rationally designed and synthesized three water-soluble aggregation-induced emission (AIE) luminogens, named PEGTPA-BTD, PEGTPA-NTD, and PEGTPA-NSD, by introducing different moieties as electron acceptors and PEGylated triphenylamine derivatives as electron donors and hydrophilic moieties. In vitro experiments showed that PEGTPA-NSD has a longer absorption and emission wavelength, where the emission wavelength can extend into NIR-II region. Besides, PEGTPA-NSD could self-assemble into stable nanoparticles in aqueous solution. Cell experiments showed that PEGTPA-NSD had no obvious dark toxicity to tumor cells or normal cells, and were easily taken in by tumor cells for cell imaging. What's more, PEGTPA-NSD NPs possessed excellent fluorescence imaging performance and biocompatibility in vivo for breast cancer bone metastases in NIR-I and NIR-II region, respectively. In summary, PEGTPA-NSD is the first reported aggregation-induced emission luminogens (AIEgens) that can self-assemble to nanoparticles in aqueous solution for NIR-I/NIR-II fluorescence imaging of breast cancer bone metastases. These findings would provide new strategies for optical diagnostic imaging of breast cancer bone metastases to better advance clinical technology development.

Triggering multiple modalities of cell death via dual-responsive nanomedicines to address the narrow therapeutic window of β-lapachone

The clinical translation of the anticancer drug β-lapachone (LAP) has been limited by the narrow therapeutic window. Stimuli-responsive anticancer drug delivery systems have gained tremendous attention in recent years to alleviate adverse effects and enhance therapeutic efficacy. Here, we report a dual pH- and enzyme-responsive nanocarrier to address the above issue of LAP. In detail, the epigallocatechin gallate (EGCG) and ferric ions were employed to engineer nanoscale ferric ion-polyphenol complexes where LAP was physically encapsulated therein. The coordination bond between Fe3+ and the catechol moiety of EGCG was sensitive to the low pH, enabling the triggered cargo release in the acidic endosomes/lysosomes. Afterward, the released LAP was activated by the overexpressed NAD(P)H: quinone oxidoreductase 1 (NQO1) and ferroptosis suppressor protein 1 (FSP1) in the tumor cells, followed by the generation of reactive oxygen species (ROS), and the induction of oxidative stress and apoptotic cell death. Meanwhile, EGCG could upregulate gasdermin E (GSDME), and ferric ions were involved in the Fenton reaction. Hence, EGCG and ferric ions could sensitize the toxicity of LAP through the induction of multiple cell death pathways (e.g., pyroptosis, ferroptosis, apoptosis, and necroptosis). The current work enlarged the LAP's therapeutic window via controlled cargo release and vehicle sensitization.

A Turbo-Charging System-Like Contrast Agent for MRI-Guided STING Pathway-Activated Cancer Immunotherapy

To overcome the problems of Gd-based contrast agents (GBCAs) (nephrotoxicity and brain deposition) and stimulator of interferon genes (STING) agonists (poor stability, low delivery efficiency, and potential toxicity), in this study, a Turbo-charging system-like GBCA is designed and constructed for magnetic resonance imaging (MRI) guided STING pathway-activated cancer immunotherapy. Poly(acrylic acid) (PAA) is used to coordinate with Gd3+, forming a Gd/PAA macrochelate. Both Gd/PAA macrochelate and SR717 are conjugated to cystamine (CA) to obtain SR717-CA@Gd/PAA self-assembled nanoparticles (SAN), which are termed as Turbo S because of its similarity with the Turbo-charging system of cars. After accumulation in tumors and internalization in tumor cells, the disulfide linkage in Turbo S undergoes a cleavage process catalyzed by glutathione (GSH), leading to the release of Gd/PAA and SR717. The released Gd/PAA gain a high r1 value (17.11 mM-1 s-1 at 7.0 T; 57.81 mM-1 s-1 at 3.0 T), indicating its strong T1 imaging capability. Turbo S with a low dosage of SR717 (8.9 mg kg-1) achieved a higher tumor immunotherapeutic efficacy than free SR717 with a high dosage (30 mg kg-1). The excellent delivery efficiency, high tumor treatment efficacy, and superior biosafety demonstrate that the Turbo S can be used as a promising candidate for tumor immunotherapy.

Magnetic Resonance Imaging-Based Radiogenomic Analysis Reveals Genomic Determinants for Nanoparticle Delivery into Tumors

Even though the enhanced permeability and retention (EPR) effect is applicable for the passive targeting of solid tumors, many nanodrugs have failed to achieve meaningful clinical outcomes due to the heterogeneity of EPR effect. Therefore, understanding the mechanism of the EPR effect is crucial to overcome the obstacles nanomedicines face in clinical translation. The aim of this study was to establish a reliable method to increase awareness of the critical influencing factors of nanoparticle (NP) transport into tumors based on the EPR effect using a combined radiogenomics and clinical magnetic resonance imaging (MRI) technique and gene set pathway enrichment analysis. Employing poly(lactic-co-glycolic acid) (PLGA)-coated Fe3O4 NPs as the contrast agent, the monolayer and multilayer distribution of the NPs were observed and quantitatively analyzed by MRI, improving the accuracy of evaluating vascular permeability by MRI. By performing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of genes and pathways, we identified a variety of genes affecting vascular permeability, such as Cldn1, Dlg2, Bves, Prkag3, Cldn10, and Cldn8, which are related to tight junctions and control the permeability of blood vessels in tumors. The method presented here provides an MRI-supported approach to increase the breadth of data collected from genetic screens, reveals genetic evidence of the presence of NPs in tumors and lays a foundation for clinical patient stratification and personalized treatment.

Hyaluronic acid-functionalized supramolecular nanophotosensitizers for targeted photoimmunotherapy of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is recognized as a particularly aggressive subtype of breast cancer that is devoid of effective therapeutic targets. Immune checkpoint inhibitors (ICIs) have demonstrated promising results in TNBC treatment. Nonetheless, most patients either develop resistance to ICIs or fail to respond to them initially. Owing to its spatio-temporal precision and non-invasive nature, photoimmunotherapy offers a targeted therapeutic strategy for TNBC. Herein, we report hyaluronic acid (HA)-functionalized indocyanine green-based supramolecular nanoparticles (HGI NPs), with biodegradable characteristics, for high-performance photoacoustic imaging and targeted phototherapy for TNBC. Notably, HGI NPs can significantly gather in TNBC tissues because of the enhanced permeability and retention effect of the tumor, and the tumor-targeting properties of HA. The strong amplification of HGI nanoparticles triggers a significant immunogenic cell death (ICD) response when exposed to 808 nm light, thus shifting the immunosuppressive tumor microenvironment (iTME) into a tumor attack mode and 'hot' state. Antitumor experiments demonstrate the high efficiency of the supramolecular photosensitizers HGI NPs for TNBC elimination and good biosafety. This synergistic strategy reshapes the iTME and amplifies the antitumor immune response, providing a theoretical foundation for combining phototherapy and ICIs as potential treatments for TNBC.

Impact of inner hydrophobicity of dendrimer nanomicelles on biodistribution: a PET imaging study

Self-assembly is a powerful strategy for building nanosystems for biomedical applications. We have recently developed small amphiphilic dendrimers capable of self-assembling into nanomicelles for tumor imaging. In this context, we studied the impact of increased hydrophobicity of the amphiphilic dendrimer on hydrophilic/hydrophobic balance and consequently on the self-assembly and subsequent biodistribution. Remarkably, despite maintaining the exact same surface chemistry, similar zeta potential, and small size, the altered and enlarged hydrophobic component within the amphiphilic dendrimer led to enhanced stability of the self-assembled nanomicelles, with prolonged circulation time and massive accumulation in the liver. This study reveals that even structural alteration within the interior of nanomicelles can dramatically impact biodistribution profiles. This finding highlights the deeper complexity of rational design for nanomedicine and the need to consider factors other than surface charge and chemistry, as well as size, all of which significantly impact the biodistribution of self-assembling nanosystems.

Engineering the Hydrophilic-Hydrophobic Interface of Polymeric Micelles by Cationic Blocks for Enhanced Chemotherapy

The cationic surface charge critically influences the biological functions and therapeutic outcomes of the cancer nanomedicines. However, the basic correlation between the cationic group categories and their therapeutic efficacy has not been elucidated. In this study, cationic polymeric nanoparticles with amino groups (primary, tertiary, and quaternary amines) as the single variable were leveraged to investigate the various effects of amino species for enhanced antitumor chemotherapy. The nanoparticles were constructed from a series of triblock polymers with varying cationic repeating units at the hydrophilic-hydrophobic interface. Our results suggested that quaternary ammonium outperforms its primary and tertiary counterparts in destroying mitochondrial membranes to induce apoptosis, penetrating deep inside the tumor tissue, and damaging tumor vasculatures. As a result, we were able to effectively inhibit tumor growth in mice by a quaternary ammonium conjugate without causing significant toxicity. Our work demonstrated that the chemical structures played vital roles in regulating their biological functions and provided valuable information for designing cationic drug delivery systems.

Functionalities of pH-responsive DNA nanostructures in tumor-targeted strategies

Nanostructures integrating pH-sensitive DNA motifs have emerged as versatile platforms for active tumor targeting, owing to their ability to undergo conformation changes in response to the common acidic environment of the tumor extracellular matrix and endocytosis pathway. This review summarizes the latest advances in the design and application of various pH-responsive DNA nanostructures for tumor-targeted strategies, including tumor recognition, cell imaging, dynamic nanocarrier construction, and controlled drug release. A comprehensive framework for pH-controlled multi-stage tumor targeting is introduced, addressing the divergences in targeting strategies for extracellular and intracellular environments. The unique attributes, practical performance and application challenges of pH-responsive DNA nanostructures are also critically discussed to provide guidance for future development in this field.

Action Programmed Nanoantibiotics with pH-Induced Collapse and Negative-Charged-Surface-Induced Deformation against Antibiotic-Resistant Bacterial Peritonitis

The incorporation of well-designed antibiotic nanocarriers, along with an antibiotic adjuvant effect, in combination with various antibiotics, offers an opportunity to combat drug-resistant strains. However, precise control over morphology and encapsulated payload release can significantly impact their antibacterial efficacy and synergistic effects when used alongside antibiotics. Here, this study focuses on developing lipopeptide-based nanoantibiotics, which demonstrate an antibiotic adjuvant effect by inducing pH-induced collapse and negative-charged-surface-induced deformation. This enhances the disruption of the bacterial outer membrane and facilitates drug penetration, effectively boosting the antimicrobial activity against drug-resistant strains. The modulation regulations of the lipopeptide nanocarriers with modular design are governed by the authors. The nanoantibiotics, made from lipopeptide and ciprofloxacin (Cip), have a drug loading efficiency of over 80%. The combination with Cip results in a significantly low fractional inhibitory concentration index of 0.375 and a remarkable reduction in the minimum inhibitory concentration of Cip against multidrug-resistant (MDR) Escherichia coli (clinical isolated strains) by up to 32-fold. The survival rate of MDR E. coli peritonitis treated with nanoantibiotics is significantly higher, reaching over 87%, compared to only 25% for Cip and no survival for the control group. Meanwhile, the nanoantibiotic shows no obvious toxicity to major organs.

Advances in the delivery of anticancer drugs by nanoparticles and chitosan-based nanoparticles

Cancer is the leading cause of death globally, and conventional treatments have limited efficacy with severe side effects. The use of nanotechnology has the potential to reduce the side effects of drugs by creating efficient and controlled anticancer drug delivery systems. Nanoparticles (NPs) used as drug carriers offer several advantages, including enhanced drug protection, biodistribution, selectivity and, pharmacokinetics. Therefore, this review is devoted to various organic (lipid, polymeric) as well as inorganic nanoparticles based on different building units and providing a wide range of potent anticancer drug delivery systems. Within these nanoparticulate systems, chitosan (CS)-based NPs are discussed with particular emphasis due to the unique properties of CS and its derivatives including non-toxicity, biodegradability, mucoadhesivity, and tunable physico-chemical as well as biological properties allowing their alteration to specifically target cancer cells. In the context of streamlining the nanoparticulate drug delivery systems (DDS), innovative nanoplatform-based cancer therapy pathways involving passive and active targeting as well as stimuli-responsive DDS enhancing overall orthogonality of developed NP-DDS towards the target are included. The most up-to-date information on delivering anti-cancer drugs using modern dosage forms based on various nanoparticulate systems and, specifically, CSNPs, are summarised and evaluated concerning their benefits, limitations, and advanced applications.

Advancements in electron paramagnetic resonance (EPR) spectroscopy: A comprehensive tool for pharmaceutical research

Electron paramagnetic resonance (EPR) spectroscopy has long been established across various scientific disciplines for characterizing organic radicals, organometallic complexes, protein structures and dynamics, polymerization processes, and radical degradation phenomena. Despite its extensive utility in these areas, EPR spectroscopy's application within pharmaceutical science has historically been constrained, primarily due to factors such as high equipment costs, a steep learning curve, complex spectral deconvolution and analysis, and a traditional lack of emphasis on single-electron chemistry in pharmaceutical research. This review aims to provide a thorough examination of EPR spectroscopy's applications in analyzing a wide array of para-magnetic species relevant to pharmaceutical research. We detail how EPR spectroscopy can be employed to assess free radical scavenging properties in pharmaceutical compounds, elucidate drug mechanisms of action, and explore pharmacokinetics. Additionally, we investigate the role of free radicals in drug-induced toxicity and drug-membrane interactions, while also covering the application of EPR spectroscopy in drug delivery research, advanced studies of metallodrugs, and monitoring of oxygen levels in biological systems through EPR oximetry. The recent advancements in the miniaturization of EPR spectro meters have paved the way for their application in on-site and in-line mo nitoring during the manufacturing process and quality control of pharmaceutical substances and final drug formulations due to being the only direct and non-invasive detection technique for radical detection. Through these discussions, we highlight the substantial contributions of EPR spectroscopy to the advancement of pharmaceutical sciences.

Metabolic reprogramming and therapeutic resistance in primary and metastatic breast cancer

Metabolic alterations, a hallmark of cancer, enable tumor cells to adapt to their environment by modulating glucose, lipid, and amino acid metabolism, which fuels rapid growth and contributes to treatment resistance. In primary breast cancer, metabolic shifts such as the Warburg effect and enhanced lipid synthesis are closely linked to chemotherapy failure. Similarly, metastatic lesions often display distinct metabolic profiles that not only sustain tumor growth but also confer resistance to targeted therapies and immunotherapies. The review emphasizes two major aspects: the mechanisms driving metabolic resistance in both primary and metastatic breast cancer, and how the unique metabolic environments in metastatic sites further complicate treatment. By targeting distinct metabolic vulnerabilities at both the primary and metastatic stages, new strategies could improve the efficacy of existing therapies and provide better outcomes for breast cancer patients.

Enzyme/pH-sensitive nanoparticles based on poly(β-L-malic acid) for drug delivery with enhanced endocytosis

Nanoparticles (NPs) derived from branched copolymers of poly (β-L-malic acid) (PMLA) have been extensively investigated for drug delivery due to their high density of pendant carboxyl groups. This abundant functional group availability enhances their potential as effective drug delivery systems; however, the strong negative charge of PMLA poses a challenge in its uptake by cancer cells due to electrostatic repulsion. In this study, we developed novel enzyme- and pH-sensitive nanoparticles (EP-NPs) based on PMLA, demonstrating tumor-specific behavior and selective activation within tumor tissues. To enhance the cellular internalization of the nanoparticles, we incorporated transactivator of transcription (TAT). In summary, long-chain polyethylene glycol (PEG) was conjugated to PMLA to confer specificity to the TAT peptide. This was achieved using a tetrapeptide linker: alanine-alanine-asparagine-leucine (AANL), which serves as a substrate for legumain. Legumain is a highly conserved cysteine protease primarily found in lysosomes and blood vessels, initially discovered in legumes. It is markedly overexpressed in numerous solid tumors, as well as in endothelial cells and tumor-associated macrophages. The release of doxorubicin in tumor cells was sustained due to the low pH (5.0-5.5) and degradation of PMLA. The PEG modification optimized the particle size and shielded the nanoparticles from plasma proteins and detection by the reticuloendothelial system, thereby prolonging their long circulation time. Once the nanoparticles reached the tumor microenvironment, the AANL was cleaved by legumain, exposing the TAT peptide on the surface, which enhances cellular internalization. Both in vitro and in vivo efficacy studies demonstrated that these EP-NPs significantly inhibited tumor growth while exhibiting negligible systemic toxicity, thereby suggesting that the developed enzyme/pH-sensitive PMLA-based nanoparticle holds great promise as an anti-tumor drug delivery system.

Preparation of Disulfide/Trisulfide Core-Cross-Linked Polycarbonate Nanocarriers for Intracellular Reduction-Triggered Drug Release

Polymeric nanocarriers have attracted significant attention in the field of anticancer drug delivery due to their unique advantages. However, designing nanocarriers that can maintain stability in the bloodstream while achieving specific drug release within tumor cells remains a major challenge. To address this issue, constructing reversible cross-linked polymeric nanocarriers that are sensitive to the intracellular reducible glutathione (GSH) characteristic of the tumor microenvironment is a promising strategy. Based on this, we designed and synthesized two novel six-membered bicyclic carbonate monomers containing disulfide (DSBC) and trisulfide (TSBC) bonds. Through a one-step ring-opening polymerization, a series of reduction-sensitive polycarbonate copolymers (i.e., PEG-PDSBC and PEG-PTSBC) were prepared, and doxorubicin (DOX)-loaded nanoparticles were fabricated using a nanoprecipitation method. The in vitro drug release behaviors of these nanoparticles were systematically investigated. The results showed that these polymers, due to the cross-linked structure formed by the ring-opening polymerization of their bicyclic monomers, could self-assemble into stable nanoparticles. Under different concentrations of glutathione, DOX-loaded PEG-PTSBC nanoparticles demonstrated faster drug release, indicating more optimized intracellular drug release properties. Further cytotoxicity experiments revealed that both types of blank nanoparticles exhibited good biocompatibility with the 4T1 and NIH-3T3 cells. Fluorescence microscopy and flow cytometry results further indicated that DOX-loaded PEG-PTSBC nanoparticles released more drugs in 4T1 cells, significantly inhibiting tumor cell growth compared with DOX-loaded PEG-PDSBC nanoparticles, with no noticeable difference in NIH-3T3 normal cells. In conclusion, this study suggests that trisulfide cross-linked polycarbonate-based nanocarriers hold promise as an anticancer drug delivery system that combines stability in the bloodstream with specific intracellular drug release, offering new insights for the development of novel, efficient, and safe anticancer nanomedicines.

Nanotechnology in healthcare, and its safety and environmental risks

Nanotechnology holds immense promise in revolutionising healthcare, offering unprecedented opportunities in diagnostics, drug delivery, cancer therapy, and combating infectious diseases. This review explores the multifaceted landscape of nanotechnology in healthcare while addressing the critical aspects of safety and environmental risks associated with its widespread application. Beginning with an introduction to the integration of nanotechnology in healthcare, we first delved into its categorisation and various materials employed, setting the stage for a comprehensive understanding of its potential. We then proceeded to elucidate the diverse healthcare applications of nanotechnology, spanning medical diagnostics, tissue engineering, targeted drug delivery, gene delivery, cancer therapy, and the development of antimicrobial agents. The discussion extended to the current situation surrounding the clinical translation and commercialisation of these cutting-edge technologies, focusing on the nanotechnology-based healthcare products that have been approved globally to date. We also discussed the safety considerations of nanomaterials, both in terms of human health and environmental impact. We presented the in vivo health risks associated with nanomaterial exposure, in relation with transport mechanisms, oxidative stress, and physical interactions. Moreover, we highlighted the environmental risks, acknowledging the potential implications on ecosystems and biodiversity. Lastly, we strived to offer insights into the current regulatory landscape governing nanotechnology in healthcare across different regions globally. By synthesising these diverse perspectives, we underscore the imperative of balancing innovation with safety and environmental stewardship, while charting a path forward for the responsible integration of nanotechnology in healthcare.

Recent Advances in Degradable Biomedical Polymers for Prevention, Diagnosis and Treatment of Diseases

Biomedical polymers play a key role in preventing, diagnosing, and treating diseases, showcasing a wide range of applications. Their unique advantages, such as rich source, good biocompatibility, and excellent modifiability, make them ideal biomaterials for drug delivery, biomedical imaging, and tissue engineering. However, conventional biomedical polymers suffer from poor degradation in vivo, increasing the risks of bioaccumulation and potential toxicity. To address these issues, degradable biomedical polymers can serve as an alternative strategy in biomedicine. Degradable biomedical polymers can efficiently relieve bioaccumulation in vivo and effectively reduce patient burden in disease management. This review comprehensively introduces the classification and properties of biomedical polymers and the recent research progress of degradable biomedical polymers in various diseases. Through an in-depth analysis of their classification, properties, and applications, we aim to provide strong guidance for promoting basic research and clinical translation of degradable biomedical polymers.

Natural Phycocyanin/Paclitaxel Micelle Delivery of Therapeutic P53 to Activate Apoptosis for HER2 or ER Positive Breast Cancer Therapy

The P53 gene is commonly mutated in breast cancer, protein based the gene as anticancer drugs could provide efficient and stable advantages by restoring the function of the wild-type P53 protein. In this study, we describe the creation and utilization of a micelle composed by natural phycocyanin and paclitaxel and grafting anti-HER2 (PPH), which effectively packages and transports recombinant P53 protein with anti-ER (PE), resulting in a new entity designated as PE@PPH, to address localization obstacles and modify cellular tropism to the cell membrane or nucleus. The results indicate that PE@PPH has strong antitumor properties, even at low doses of PTX both in vitro and in vivo. These findings suggest that PE@PPH could be an enhancing micelle for delivering therapeutic proteins and promoting protein functional recovery, particularly in addressing the challenges posed by tumor heterogeneity in breast cancer.

The unexpected PD-L1 suppression function of celery-derived extracellular vesicles improves lung cancer chemotherapy efficacy

Aim: The article explores celery-derived extracellular vesicles (CDEVs), characterized by high cellular uptake, low immunogenicity, and high stability, as a therapeutic strategy for antitumor nanomedicines. Methods: The methods employed in this study include in vitro cell experiments such as co-culture, Western Blot, and flow cytometry. In vivo experiments were conducted in C57BL/6 tumor-bearing mice subcutaneously injected with Lewis lung carcinoma (LLC) cells. The experiments encompassed parameters such as survival rate, body weight, tumor size, flow cytometry, immunohistochemistry, and spectral live imaging system. Results: Our study revealed that CDEVs could be used as drugs to effectively downregulate the phosphorylated signal transducer and activator of transcription 3 (p-STAT3)/programmed cell death ligand 1 (PD-L1) axis in lung cancer cells. In co-culture experiments, CDEVs were observed to impede the expression of PD-L1, thereby interfering with the interaction between PD-L1 and programmed death 1 (PD-1) and subsequently preventing the suppression of T cells. In in vivo distribution experiments, CDEVs loaded with paclitaxel (PTX) demonstrated better tumor targeting capabilities. Remarkably, following CDEVs-PTX treatment, CD8+ T cell levels in mice were increased, presumably leading to improved antitumor effects. Conclusion: CDEVs not only serve as drug carriers but also function as drugs themselves; as such, through a single administration of CDEVs, it is possible to combine immunotherapy and chemotherapy to achieve better effects between the two, providing a more comprehensive and effective cancer treatment strategy that promises to improve treatment outcomes and reduce the adverse effects of therapy.

Harnessing Gene Editing Technology for Tumor Microenvironment Modulation: An Emerging Anticancer Strategy

Cancer is a multifaceted disease influenced by both intrinsic cellular traits and extrinsic factors, with the tumor microenvironment (TME) being crucial for cancer progression. To satisfy their high proliferation and aggressiveness, cancer cells always plunder large amounts of nutrients and release various signals to their surroundings, forming a dynamic TME with special metabolic, immune, microbial and physical characteristics. Due to the neglect of interactions between tumor cells and the TME, traditional cancer therapies often struggle with challenges such as drug resistance, low efficacy, and recurrence. Importantly, the development of gene editing technologies, particularly the CRISPR-Cas system, offers promising new strategies for cancer treatment. Combined with nanomaterial strategies, CRISPR-Cas technology exhibits precision, affordability, and user-friendliness with reduced side effects, which holds great promise for profoundly altering the TME at the genetic level, potentially leading to lasting anticancer outcomes. This review will delve into how CRISPR-Cas can be leveraged to manipulate the TME, examining its potential as a transformative anticancer therapy.

pH-Responsive Charge-Reversal Smart Nanoparticles for Co-Delivery of Mitoxantrone and Copper Ions to Enhance Breast Cancer Chemo-Chemodynamic Combination Therapy

Purpose

The poor delivery and limited penetration of nanoparticles into breast cancer tumors remain essential challenges for effective anticancer therapy. This study aimed to design a promising nanoplatform with efficient tumor targeting and penetration capability for effective breast cancer therapy.

Methods

A pH-sensitive mitoxantrone (MTO) and copper ion-loaded nanosystem functionalized with cyclic CRGDfK and r9 peptide (TPRN-CM) was rationally designed for chemo-chemodynamic combination therapy. TPRN-CM would be quiescent in blood circulation with the CRGDfK peptide on the surface of the nanoparticle to improve its targeting to the tumor. Then, the structure of TPRN-CM changes in the acidic tumor microenvironment, and the r9 peptide can be exposed to make a surface charge reversal to promote deep penetration in the tumor and facilitate their internalization by cancer cells, which was characterized using transmission electron microscopy, dynamic light scattering, flame atomic absorption, etc. The drug release behavior, anti-tumor effects in vivo and in vitro, and the biosafety of the nanoplatform were evaluated.

Results

TPRN-CM exhibited remarkable capability to load MTO and Cu2+ with good stability in serum. It can achieve pH-responsive charge reversal, MTO, and Cu2+ release, and can further generate toxic hydroxyl radicals in the presence of glutathione (GSH) and H2O2. In vitro experiments demonstrated that this nanoplatform significantly inhibited proliferation, migration, invasion activities and 3D-tumorsphere growth. In vivo experiments suggested that rationally designed TPRN-CM can be effectively delivered to breast cancer tumors with deep tumor penetration, thereby resulting in a notable reduction in tumor growth and suppression of lung metastasis without causing any apparent side effects.

Conclusion

The constructed TPRN-CM nanoplatform integrated tumor targeting, tumor penetration, drug-responsive release, and chemo-chemodynamic combination therapy, thereby providing an intelligent drug delivery strategy to improve the efficacy of breast cancer treatment.

Smart nanocarriers for enzyme-activated prodrug therapy

Exogenous enzyme-activated prodrug therapy (EPT) is a potential cancer treatment strategy that delivers non-human enzymes into or on the surface of the cell and subsequently converts a non-toxic prodrug into an active cytotoxic substance at a specific location and time. The development of several pharmacological pairs based on EPT has been the focus of anticancer research for more than three decades. Numerous of these pharmacological pairs have progressed to clinical trials, and a few have achieved application in specific cancer therapies. The current review highlights the potential of enzyme-activated prodrug therapy as a promising anticancer treatment. Different microbial, plant, or viral enzymes and their corresponding prodrugs that advanced to clinical trials have been listed. Additionally, we discuss new trends in the field of enzyme-activated prodrug nanocarriers, including nanobubbles combined with ultrasound (NB/US), mesoscopic-sized polyion complex vesicles (PICsomes), nanoparticles, and extracellular vesicles (EVs), with special emphasis on smart stimuli-triggered drug release, hybrid nanocarriers, and the main application of nanotechnology in improving prodrugs.

Rational design of pH-responsive nano-delivery system with improved biocompatibility and targeting ability from cellulose nanocrystals via surface polymerization for intracellular drug delivery

Cellulose nanocrystals (CNCs), derived from diverse sources and distinguished by their inherent biodegradability, excellent biocompatibility, and facile cellular engulfment due to their rod-like structure, hold great promise as carriers for the development of nano-delivery systems. In this work, highly efficient rod-like CNCs were employed as substrates for grafting glycidyl onto their surfaces through ring-opening polymerization, forming hyperbranched polymers with superior cell uptake properties. Subsequently, 4-vinylbenzeneboronic acid (VB) and poly (ethylene glycol) methyl ether methacrylate (PEGMA) were employed as monomers in the polymerization process to fabricate a pH-responsive targeted nano-delivery system, denoted as CNCs-VB-PEGMA, via single electron transfer reactive radical polymerization (SET-LRP) reaction. The CNCs-VB-PEGMA was successfully prepared and used for the loading of curcumin (Cur) to form a pH-responsive nano-delivery system (CNCs-VB-PEGMA-Cur), and the loading rate of Cur was as high as 70.0 %. Studies showed that this drug delivery system could actively targeting liver cancer cells with the 2D cells model and 3D tumor microsphere model, showing efficient liver cancer cell-killing ability. Collectively, the CNCs-VB-PEGMA drug delivery system has potential applications in liver cancer therapy as an actively targeting and pH-responsive drug delivery system.

The future of genetic medicines delivered via targeted lipid nanoparticles to leukocytes

Genetic medicines hold vast therapeutic potential, offering the ability to silence or induce gene expression, knock out genes, and even edit DNA fragments. Applying these therapeutic modalities to leukocytes offers a promising path for treating various conditions yet overcoming the obstacles of specific and efficient delivery to leukocytes remains a major bottleneck in their clinical translation. Lipid nanoparticles (LNPs) have emerged as the leading delivery system for nucleic acids due to their remarkable versatility and ability to improve their in vivo stability, pharmacokinetics, and therapeutic benefits. Equipping LNPs with targeting moieties can promote their specific cellular uptake and internalization to leukocytes, making targeted LNPs (tLNPs) an inseparable part of developing leukocyte-targeted gene therapy. However, despite the significant advancements in research, genetic medicines for leukocytes using targeted delivery approaches have not been translated into the clinic yet. Herein, we discuss the important aspects of designing tLNPs and highlight the considerations for choosing an appropriate bioconjugation strategy and targeting moiety. Furthermore, we provide our insights on limiting challenges and identify key areas for further research to advance these exciting therapies for patient care.

Challenges and opportunities of poly(amino acid) nanomedicines in cancer therapy

Poly(amino acid) nanomedicines hold significant promise for cancer therapy. However, their clinical translation has not matched the extensive efforts of scientists or the burgeoning body of research. The therapeutic outcomes with most nanomedicines often fall short of the promising results observed in animal experiments. This review explores the challenges faced in cancer therapy using poly(amino acid) nanomedicines, particularly addressing the controversies surrounding the enhanced permeability and retention effect and the lack of methods for controlled and reproducible mass production of poly(amino acid) nanomedicines. Furthermore, this review examines the opportunities emerging in this field due to the rapid advancements in artificial intelligence.

The Chemo-Immunotherapeutic Roles of Tumor-Derived Extracellular Vesicle-Based Paclitaxel Delivery System in Hepatocarcinoma

As a first-line chemotherapeutic agent, albumin-bound paclitaxel (PA) has a considerable effect on the treatment of various cancers. However, in chemotherapy for hepatocarcinoma, the sensitivity to PA is low owing to the innate resistance of hepatocarcinoma cells; the toxicity and side effects are severe, and the clinical treatment impact is poor. In this study, we present a unique nanodrug delivery system. The ultraviolet (UV)-induced tumor-cell-derived extracellular vesicles (EVs) were isolated and purified by differential centrifugation. Then, PA was loaded by coextrusion to create a vesicle drug delivery system (EVPA). By employing the EV-dependent enhanced retention effect and specific homing effect, EVPA would passively and actively target tumor tissues, activate the immune response to release PA, and achieve the combination therapeutic effect of chemo-immunotherapy on hepatocarcinoma. We demonstrated that the tumor-killing effect of EVPA is superior to that of PA, both in vivo and in vitro and that EVPA can be effectively taken up by hepatocarcinoma and dendritic cells, activate the body's specific immune response, promote the infiltration of CD4+ and CD8+ T cells in tumor tissues, and exert a precise killing effect on hepatocarcinoma cells via chemo-immunotherapy.

Surface-engineered erythrocyte membrane-camouflage fluorescent bioprobe for precision ovarian cancer surgery

PURPOSE

Fluorescence imaging-guided surgery has been used in oncology. However, for tiny tumors, the current imaging probes are still difficult to achieve high-contrast imaging, leading to incomplete resection. In this study, we achieved precise surgical resection of tiny metastatic cancers by constructing an engineering erythrocyte membrane-camouflaged bioprobe (AR-M@HMSN@P).

METHODS

AR-M@HMSN@P combined the properties of aggregation-induced emission luminogens (AIEgens) named PF3-PPh3 (P), with functional erythrocyte membrane modified by a modular peptide (AR). Interestingly, AR was composed of an asymmetric tripodal pentapeptide scaffold (GGKGG) with three appended modulars: KPSSPPEE (A6) peptide, RRRR (R4) peptide and cholesterol. To verify the specificity of the probe in vitro, SKOV3 cells with overexpression of CD44 were used as the positive group, and HLF cells with low expression of CD44 were devoted as the control group. The AR-M@HMSN@P fluorescence imaging was utilized to provide surgical guidance for the removal of micro-metastatic lesions.

RESULTS

In vivo, the clearance of AR-M@HMSN@P by the immune system was reduced due to the natural properties inherited from erythrocytes. Meanwhile, the A6 peptide on AR-M@HMSN@P was able to specifically target CD44 on ovarian cancer cells, and the electrostatic attraction between the R4 peptide and the cell membrane enhanced the firmness of this targeting. Benefiting from these multiple effects, AR-M@HMSN@P achieved ultra-precise tumor imaging with a signal-to-noise ratio (SNR) of 15.2, making it possible to surgical resection of tumors < 1 mm by imaging guidance.

CONCLUSION

We have successfully designed an engineered fluorescent imaging bioprobe (AR-M@HMSN@P), which can target CD44-overexpressing ovarian cancers for precise imaging and guide the resection of minor tumors. Notably, this work holds significant promise for developing biomimetic probes for clinical imaging-guided precision cancer surgery by exploiting their externally specified functional modifications.

Graphene oxide nanoribbons conjugated with 1, 2-distearoyl-sn-glycero-3 phosphoethanolamine-poly (ethylene glycol)-transferrin enhanced targeted delivery and cytotoxicity of raloxifene against breast cancer

The clinical utility of raloxifene (RLX), a selective estrogen receptor modulator (SERM), has been compromised by severe side effects and unfavorable drug properties. To address these, a transferrin (Tf) conjugated graphene oxide nanoribbon (GONR) platform was tried for RLX. The stability of GONRs in biological media was improved by surface modification with 1, 2-Distearoyl-sn-glycero-3 phosphoethanolamine-Poly (ethylene glycol) (DSPE-PEG). The Tf molecule was covalently attached to DSPE-PEG (DPT) using EDC-NHS chemistry. The surface of GONR was then modified with DSPE-PEG (DP) or DPT and loaded with RLX (GDP-RLX and GDPT-RLX). The final formulations were characterized for drug loading and stability. The anticancer activities of pure RLX, GDP-RLX, and GDPT-RLX were evaluated and compared in all the in vitro and in vivo studies. In vitro cell line studies showed that GDPT-RLX have significantly high cytotoxicity, cellular uptake, apoptosis induction, G2/M phase arrest, anti-migration properties, and apoptotic protein expression, followed by GDP-RLX and RLX. Pharmacokinetics and tumor biodistribution were also found to be excellent with GDPT-RLX. The in vivo tumor therapy and tumor evaluation outcomes were also consistent with the in vitro data. The Tf conjugated GDPT-RLX represents a promising approach for targeted and sustained delivery of RLX with enhanced therapeutic efficacy.

Natural compounds-based nanomedicines for cancer treatment: Future directions and challenges

Several efforts have been extensively accomplished for the amelioration of the cancer treatments using different types of new drugs and less invasives therapies in comparison with the traditional therapeutic modalities, which are widely associated with numerous drawbacks, such as drug resistance, non-selectivity and high costs, restraining their clinical response. The application of natural compounds for the prevention and treatment of different cancer cells has attracted significant attention from the pharmaceuticals and scientific communities over the past decades. Although the use of nanotechnology in cancer therapy is still in the preliminary stages, the application of nanotherapeutics has demonstrated to decrease the various limitations related to the use of natural compounds, such as physical/chemical instability, poor aqueous solubility, and low bioavailability. Despite the nanotechnology has emerged as a promise to improve the bioavailability of the natural compounds, there are still limited clinical trials performed for their application with various challenges required for the pre-clinical and clinical trials, such as production at an industrial level, assurance of nanotherapeutics long-term stability, physiological barriers and safety and regulatory issues. This review highlights the most recent advances in the nanocarriers for natural compounds secreted from plants, bacteria, fungi, and marine organisms, as well as their role on cell signaling pathways for anticancer treatments. Additionally, the clinical status and the main challenges regarding the natural compounds loaded in nanocarriers for clinical applications were also discussed.

Ultrasmall Metal TPZ Complexes with Deep Tumor Penetration for Enhancing Radiofrequency Ablation Therapy and Inducing Antitumor Immune Responses

Radiofrequency ablation (RFA) is one of the most common minimally invasive techniques for the treatment of solid tumors, but residual malignant tissues or small satellite lesions after insufficient RFA (iRFA) are difficult to remove, often leading to metastasis and recurrence. Here, Fe-TPZ nanoparticles are designed by metal ion and (TPZ) ligand complexation for synergistic enhancement of RFA residual tumor therapy. Fe-TPZ nanoparticles are cleaved in the acidic microenvironment of the tumor to generate Fe2+ and TPZ. TPZ, an anoxia-dependent drug, is activated in residual tumors and generates free radicals to cause tumor cell death. Elevated Fe2+ undergoes a redox reaction with glutathione (GSH), inducing a strong Fenton effect and promoting the production of the highly toxic hydroxyl radical (•OH). In addition, the ROS/GSH imbalance induced by this treatment promotes immunogenic cell death (ICD), which triggers the release of damage-associated molecular patterns, macrophage polarization, and lymphocyte infiltration, thus triggering a systemic antitumor immune response and noteworthy prevention of tumor metastasis. Overall, this integrated treatment program driven by multiple microenvironment-dependent pathways overcomes the limitations of the RFA monotherapy approach and thus improves tumor prognosis. Furthermore, these findings aim to provide new research ideas for regulating the tumor immune microenvironment.

Development of dual-crosslinked Pluronic F127/Chitosan injectable hydrogels incorporating graphene nanosystems for breast cancer photothermal therapy and antibacterial applications

Nanomaterials with responsiveness to near-infrared light can mediate the photoablation of cancer cells with an exceptional spatio-temporal resolution. However, the therapeutic outcome of this modality is limited by the nanostructures' poor tumor uptake. To address this bottleneck, it is appealing to develop injectable in situ forming hydrogels due to their capacity to perform a tumor-confined delivery of the nanomaterials with minimal off-target leakage. In particular, injectable in situ forming hydrogels based on Pluronic F127 have been emerging due to their FDA-approval status, biocompatibility, and thermosensitive sol-gel transition. Nevertheless, the application of Pluronic F127 hydrogels has been limited due to their fast dissociation in aqueous media. Such limitation may be addressed by combining the thermoresponsive sol-gel transition of Pluronic F127 with other polymers with crosslinking capabilities. In this work, a novel dual-crosslinked injectable in situ forming hydrogel based on Pluronic F127 (thermosensitive gelation) and Chitosan (ionotropic gelation in the presence of NaHCO3), loaded with Dopamine-reduced graphene oxide (DOPA-rGO; photothermal nanoagent), was developed for application in breast cancer photothermal therapy. The dual-crosslinked hydrogel incorporating DOPA-rGO showed a good injectability (through 21 G needles), in situ gelation capacity and cytocompatibility (viability > 73 %). As importantly, the dual-crosslinking improved the hydrogel's porosity and prevented its premature degradation. After irradiation with near-infrared light, the dual-crosslinked hydrogel incorporating DOPA-rGO produced a photothermal heating (ΔT ≈ 22 °C) that reduced the breast cancer cells' viability to just 32 %. In addition, this formulation also demonstrated a good antibacterial activity by reducing the viability of S. aureus and E. coli to 24 and 33 %, respectively. Overall, the dual-crosslinked hydrogel incorporating DOPA-rGO is a promising macroscale technology for breast cancer photothermal therapy and antimicrobial applications.

Exploring the therapeutic potential of lipid-based nanoparticles in the management of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a highly malignant and invasive tumor with significant mortality and morbidity. Current treatment modalities such as surgery, radiotherapy, and chemotherapy encounter significant limitations, such as poor targeting, systemic toxicity, and drug resistance. There is an urgent need for novel therapeutic strategies that offer targeted delivery, enhanced efficacy, and reduced side effects. The advent of lipid-based nanoparticles (LNPs) offers a promising tool for OSCC therapy, potentially overcoming the limitations of current therapeutic approaches. LNPs are composed of biodegradable and biocompatible lipids, which minimize the risk of toxicity and adverse effects. LNPs can encapsulate hydrophobic drugs, improving their solubility and stability in the biological environment, thereby enhancing their bioavailability. LNPs demonstrate significantly higher ability to encapsulate lipophilic drugs than other nanoparticle types. LNPs offer excellent storage stability, minimal drug leakage, and controlled drug release, making them highly effective nanoplatforms for the delivery of chemotherapeutic agents. Additionally, LNPs can be modified by complexing them with specific target ligands on their surface. This surface modification allows the active targeting of LNPs to the tumors in addition to the passive targeting mechanism. Furthermore, the PEGylation of LNPs improves their hydrophilicity and enhances their biological half-life by reducing clearance by the reticuloendothelial system. This review aims to discuss current treatment approaches and their limitations, as well as recent advancements in LNPs for better management of OSCC.

Hybrid cell membranes camouflage liposomes containing payloads to improve breast cancer chemo and photodynamic therapy

The treatment of unresectable locally advanced triple-negative breast cancer (TNBC) and TNBC with metastasis is challenging. Many anticancer drugs, such as doxorubicin, still hinder positive therapeutic outcomes due to severe side effects. Photodynamic therapy (PDT) has an anticancer effect, and combining PDT with chemotherapy may improve breast cancer therapy. The use of cargo-loaded biomimetic PEGylated liposomes for cancer therapy may enhance efficacy and reduce side effects. In this study, liposomes were formulated to accommodate doxorubicin (Dox) and IR780. Breast cancer cells (4T1 cells) and macrophage cell membranes were isolated and camouflaged onto the PEGylated liposomes, creating a new biomimetic platform called Dox-IR780@Lip@Ms. The Dox-IR780@Lip@Ms platform was characterized and tested in vitro and in vivo. The results showed that the Dox-IR780@Lip@Ms had an ovoid shape with a double lamina structure, monodispersity, and uniform distribution. The size was 132.37 ± 1.22 nm, the PDI was 0.044 ± 0.067, and the zeta potential was -9.67 ± 1.08 mV. The encapsulation efficiency of Dox and IR780 in Dox-IR780@Lip@Ms was 89.36% ± 3.07% and 92.34% ± 0.66%, respectively. The release rate of Dox from Dox-IR780@Lip@Ms was good after laser irradiation. At pH 7.4, the release rate of Dox was 23.85% ± 0.62% at 3 h without laser irradiation and 36.62% ± 1.32% at 3.5 h with laser irradiation. At pH 6.5, the release rate of Dox was 32.54% ± 0.32% at 3 h without laser irradiation and 62.79% ± 2.15% at 3.5 h with laser irradiation. The cytotoxicity of IR780@Lip@Ms was lower than that of Dox-IR780@Lip@Ms. The cell uptake and generation of reactive oxygen species of Dox-IR780@Lip@Ms were significant. Dox-IR780@Lip@Ms exhibited immune escaping ability in vitro, homotypic targeting ability to cancer cells, high capability to kill cancer cells after laser irradiation, minimal cardiotoxicity, increased accumulation of Dox and IR780 in the tumor, and an increased anticancer effect in a tumor-bearing animal model. In conclusion, hybrid cell membranes of breast cancer and macrophages camouflaging PEGylated liposomes loaded with Dox and IR780 can significantly improve breast cancer therapy after laser irradiation in murine models.

Transvascular transport of nanocarriers for tumor delivery

Nanocarriers (NCs) play a crucial role in delivering theranostic agents to tumors, making them a pivotal focus of research. However, the persistently low delivery efficiency of engineered NCs has been a significant challenge in the advancement of nanomedicine, stirring considerable debate. Transvascular transport is a critical pathway for NC delivery from vessels to tumors, yet a comprehensive understanding of the interactions between NCs and vascular systems remains elusive. In recent years, considerable efforts have been invested in elucidating the transvascular transport mechanisms of NCs, leading to promising advancements in tumor delivery and theranostics. In this context, we highlight various delivery mechanisms, including the enhanced permeability and retention effect, cooperative immune-driven effect, active transcytosis, and cell/bacteria-mediated delivery. Furthermore, we explore corresponding strategies aimed at enhancing transvascular transport of NCs for efficient tumor delivery. These approaches offer intriguing solutions spanning physicochemical, biological, and pharmacological domains to improve delivery and therapeutic outcomes. Additionally, we propose a forward-looking delivery framework that relies on advanced tumor/vessel models, high-throughput NC libraries, nano-bio interaction datasets, and artificial intelligence, which aims to guide the design of next-generation carriers and implementation strategies for optimized delivery.

Thiophene assisted cellular uptake enhancement for highly efficient NIR-II cancer phototheranostics

We designed two series of NIR-II PTAs with D-A or D-A-D structures, in which the introduction of thiophene promotes a bathochromic shift of emission into the NIR-II region, helps to improve the cellular uptake of the PTAs and facilitates NIR-II imaging-guided PDT/PTT cancer phototherapy.

Recent advances in near-infrared stimulated nanohybrid hydrogels for cancer photothermal therapy

Nanomedicine has emerged as a promising avenue for advancing cancer treatment, but the challenge of mitigating its in vivo side effects necessitates the development of innovative structures and materials. Recent investigation has unveiled nanogels as particularly compelling candidates, characterized by a porous, three-dimensional network architecture that exhibits exceptional drug loading capacity. Beyond this, nanogels boast a substantial specific surface area and can be tailored with specific chemical functionalities. Consequently, nanogels are frequently engineered as a multi-modal synergistic platform for combating cancer, wherein photothermal therapy stands out due to its capacity to penetrate deep tissues and achieve localized tumor eradication through the application of elevated temperatures. In this review, we delve into the synthesis of diverse varieties of photothermal nanogels capable of controlled drug release triggered by either chemical or physical stimuli. It also summarizes their potential for synergistic integration with photothermal therapy alongside other therapeutic modalities to realize effective tumor ablation. Moreover, we analyze the primary mechanisms underlying the contribution of photothermal nanogels to cancer treatment while underscoring their adeptness in regulating therapeutic temperatures for repairing bone defects resulting from tumor-associated trauma. Envisioned as an auspicious strategy in the realm of cancer therapy, photothermal nanogels hold promise for furnishing controlled drug delivery and precise thermal ablation capabilities.