Rational nanocarrier design towards clinical translation of cancer nanotherapy

Evodiamine and its nano-based approaches for enhanced cancer therapy: recent advances and challenges

Evodiamine is a bioactive alkaloid extracted from the Evodia rutaecarpa plant. It has various pharmacological effects including anti-cancer, anti-bacterial, anti-obesity, anti-neurodegenerative, anti-depressant, and cardiac protective properties. Evodiamine demonstrates potent anti-cancer activity by inhibiting the proliferation of cancer cells in vitro and in vivo. Despite the health-promoting properties of evodiamine, its clinical use is hindered by low water solubility, poor bioavailability, and toxicity. Thus, there is a need to develop alternative drug delivery systems for evodiamine to enhance its solubility, permeability, and stability, as well as to facilitate targeted, prolonged, and controlled drug release. Nanocarriers can increase the therapeutic potential of evodiamine in cancer therapy while reducing adverse side effects. To date, numerous attempts have been made through the development of smart nanocarriers to overcome the drawbacks of evodiamine. This review focuses on the pharmacological applications, anti-cancer mechanisms, and limitations of evodiamine. Various nanocarriers, including lipid-based nanoparticles, polymeric nanoparticles, cyclodextrins, and so forth, have been discussed extensively for evodiamine delivery. Nano-drug delivery systems could increase the solubility, bioavailability, stability, and therapeutic efficacy of evodiamine. This review aims to present a comprehensive and critical evaluation of several nano-formulations of evodiamine for cancer therapy. © 2024 Society of Chemical Industry.

Navigating Neurotoxicity and Safety Assessment of Nanocarriers for Brain Delivery: Strategies and Insights

Nanomedicine, an area that uses nanomaterials for theragnostic purposes, is advancing rapidly, particularly in the detection and treatment of neurodegenerative diseases. The design of nanocarriers can be optimized to enhance drug bioavailability and targeting to specific organs, improving therapeutic outcomes. However, clinical translation hinges on biocompatibility and safety. Nanocarriers can cross the blood-brain barrier (BBB), potentially causing neurotoxic effects through mechanisms such as oxidative stress, DNA damage, and neuroinflammation. Concerns about their accumulation and persistence in the brain make it imperative to carry out a nanotoxicological risk assessment. Generally, this involves identifying exposure sources and routes, characterizing physicochemical properties, and conducting cytotoxicity assays both in vitro and in vivo. The lack of a specialized regulatory framework creates substantial gaps, making it challenging to translate findings across development stages. Additionally, there is a pressing need for innovative testing methods due to constraints on animal use and the demand for high-throughput screening. This review examines the mechanisms of nanocarrier-induced neurotoxicity and the challenges in risk assessment, highlighting the impact of physicochemical properties and the advantages and limitations of current neurotoxicity evaluation models. Future perspectives are also discussed. Additional guidance is crucial to improve the safety of nanomaterials and reduce associated uncertainty. STATEMENT OF SIGNIFICANCE: Nanocarriers show tremendous potential for theragnostic purposes in neurological diseases, enhancing drug targeting to the brain, and improving biodistribution and pharmacokinetics. However, their neurotoxicity is still a major field to be explored, with only 5% of nanotechnology-related publications addressing this matter. This review focuses on the issue of neurotoxicity and safety assessment of nanocarriers for brain delivery. Neurotoxicity-relevant exposure sources, routes, and molecular mechanisms, along with the impact of the physicochemical properties of nanomaterials, are comprehensively described. Moreover, the different experimental models used for neurotoxicity evaluation are explored at length, including their main advantages and limitations. To conclude, we discuss current challenges and future perspectives for a better understanding of risk assessment of nanocarriers for neurobiomedical applications.

Development and Characterization of Curcumin-Loaded TPGS/F127/P123 Polymeric Micelles as a Potential Therapy for Colorectal Cancer

Colorectal cancer (CRC) is the third most prominent cancer worldwide, and the second leading cause of cancer death. Poor outcomes and limitations of current treatments fuel the search for new therapeutic options. Curcumin (CUR) is often presented as a safer alternative for cancer treatment with a staggering number of molecular targets involved in tumor initiation, promotion, and progression. Despite being promising, its therapeutic potential is hindered due to its hydrophobic nature. Hence, the ongoing development of optimal delivery strategies based on nanotechnology, such as polymeric micelles (PMs), to overcome issues in CUR solubilization and delivery to tumor cells. In this sense, this study aimed to optimize the development and stability of CUR-loaded P123:F127:TPGS PMs (PFT:CUR) based on the thin-film approach and evaluate their therapeutic potential in CRC. Overall, the results revealed that the solubility of CUR was improved when room temperature was used to hydrate the film. The PFT-CUR hydrated at room temperature presents an average hydrodynamic diameter of 15.9 ± 0.3 nm with a polydispersity index (PDI) of 0.251 ± 0.103 and a zeta potential of -1.5 ± 1.9 mV, and a 35.083 ± 1.144 encapsulation efficiency (EE%) and 3.217 ± 0.091 drug loading (DL%) were observed. To ensure the stability of the optimized PFT-CUR nanosystems, different lyophilization protocols were tested, the use of 1% of glycine (GLY) being the most promising protocol. Regarding the critical micellar concentration (CMC), it was shown that the cryoprotectant and the lyophilization process could impact it, with an increase from 0.064 mg/mL to 0.119 mg/mL. In vitro results showed greater cytotoxic effects when CUR was encapsulated compared to its free form, yet further analysis revealed the heightened cytotoxicity could be attributed to the system itself. Despite challenges, the developed CUR-loaded PM shows potential as an effective therapeutic agent for CRC. Nonetheless, the system must undergo refinements to enhance drug entrapment as well as improve overall stability.

"Click" amphotericin B in prodrug nanoformulations for enhanced systemic fungemia treatment

Severe nephrotoxicity and infusion-related side effects pose significant obstacles to the clinical application of Amphotericin B (AmB) in life-threatening systemic fungal infections. In pursuit of a cost-effective and safe formulation, we have introduced multiple phenylboronic acid (PBA) moieties onto a linear dendritic telodendrimer (TD) scaffold, enabling effective AmB conjugation via boronate chemistry through a rapid, high yield, catalysis-free and dialysis-free "Click" drug loading process. Optimized AmB-TD prodrugs self-assemble into monodispersed micelles characterized by small particle sizes and neutral surface charges. AmB prodrugs sustain drug release in circulation, which is accelerated in response to the acidic pH and Reactive Oxygen Species (ROS) in the infection and inflammation. Prodrugs mitigate the AmB aggregation status, reduce cytotoxicity and hemolytic activity compared to Fungizone®, and demonstrate superior antifungal activity to AmBisome®. AmB-PEG5kBA4 has a comparable maximum tolerated dose (MTD) to AmBisome®, while over 20-fold increase than Fungizone®. A single dose of AmB-PEG5kBA4 demonstrates superior efficacy to Fungizone® and AmBisome® in treating systemic fungal infections in both immunocompetent and immunocompromised mice.

A systematic review of nanocarriers for treatment of urologic cancers

Nanocarriers (NCs) are a form of nanotechnology widely investigated in cancer treatment to improve the safety and efficacy of systemic therapies by increasing tumor specificity. Numerous clinical trials have explored the use of NCs in urologic cancers since the approval of the first NCs for cancer treatment over 20 years ago. The objective of this systematic review is to examine the effectiveness and safety of NCs in treating urological cancers. This paper summarizes the state of the field by investigating peer-reviewed, published results from 43 clinical trials involving the use of NCs in bladder, prostate, and kidney cancer patients with a focus on safety and efficacy data. Among the 43 trials, 16 were phase I, 20 phase II, and 4 phase I/II. No phase III trials have been reported. While both novel and classic NCs have been explored in urologic cancers, NCs already approved for the treatment of other cancers were more widely represented. Trials in prostate cancer and mixed trials involving both urologic and non-urologic cancer patients were the most commonly reported trials. Although NCs have demonstrable efficacy with adequate safety in non-urologic cancer patient populations, current clinical stage NC options appear to be less beneficial in the urologic cancer setting. For example, nab-paclitaxel and liposomal doxorubicin have proven ineffective in the treatment of urologic cancers despite successes in other cancers. However, several ongoing pre-clinical studies using targeted and locally applied improved NCs may eventually improve their utility.

Catalytic MnWO4 Nanorods for Chemodynamic Therapy Synergized Radiotherapy of Triple Negative Breast Cancer

Nanomedicine‐based synergy of chemodynamic therapy (CDT) and radiotherapy (RT) modulated by tumor microenvironment enables rapid tumor ablation, which holds great hope for the refractory and recurrent cancers, such as triple negative breast cancer (TNBC). The clinical translation of hafnium oxide (HfO2), commercially named as NBTXR3, has aroused new research focus on single‐component inorganic nanomedicines as clinical candidates. Herein, the single‐component MnWO4 is first reported as a new kind of Fenton‐like agent yet radiosensitizer for TNBC treatment undergoing the synergistic CDT/RT mechanism. MnWO4 nanorods are synthesized via a simple one‐pot hydrothermal method and then undergo a layer‐by‐layer PEGylation to obtain bioavailable MnWO4‐PEG (MWP). MWP‐based Fenton‐like reaction efficacy depends on reaction time, temperatures, pH values, and MWP concentrations. Mn‐triggered chemodynamic effect delays RT‐induced DNA damage repair and sorts cell cycles distribution toward radiosensitive phases, while W‐mediated radiosensitization improves the tumoral H2O2 overexpression to enhance CDT, remarkably amplifying of the intracellular oxidative stress to boost 4T1 cell apoptosis. In vitro and in vivo evaluations further demonstrate the effectiveness and biosafety of MWP‐based synergistic therapy. Considering the potential magnetic resonance and computed tomography imaging capabilities, MWP can be expected as an intelligent cancer theranostics for imaging‐guided cancer therapy in clinic in the future.

Metastatic Breast Cancer: Review of Emerging Nanotherapeutics

Metastases of breast cancer (BC) are often referred to as stage IV breast cancer due to their severity and high rate of mortality. The median survival time of patients with metastatic BC is reduced to 3 years. Currently, the treatment regimens for metastatic BC are similar to the primary cancer therapeutics and are limited to conventional chemotherapy, immunotherapy, radiotherapy, and surgery. However, metastatic BC shows organ-specific complex tumor cell heterogeneity, plasticity, and a distinct tumor microenvironment, leading to therapeutic failure. This issue can be successfully addressed by combining current cancer therapies with nanotechnology. The applications of nanotherapeutics for both primary and metastatic BC treatments are developing rapidly, and new ideas and technologies are being discovered. Several recent reviews covered the advancement of nanotherapeutics for primary BC, while also discussing certain aspects of treatments for metastatic BC. This review provides comprehensive details on the recent advancement and future prospects of nanotherapeutics designed for metastatic BC treatment, in the context of the pathological state of the disease. Furthermore, possible combinations of current treatment with nanotechnology are discussed, and their potential for future transitions in clinical settings is explored.

Engineering Telodendrimer Nanocarriers for Monomeric Amphotericin B Delivery

Systemic fungal infections are an increasingly prevalent health problem. Amphotericin B (AmB), a hydrophobic polyene antibiotic, remains the drug of choice for life-threatening invasive fungal infections. However, it has dose-limiting side effects, including nephrotoxicity. The efficacy and toxicity of AmB are directly related to its aggregation state. Here, we report the preparation of a series of telodendrimer (TD) nanocarriers with the freely engineered core structures for AmB encapsulation to fine-tune AmB aggregation status. The reduced aggregation status correlates well with the optimized antifungal activity, attenuated hemolytic properties, and reduced cytotoxicity to mammalian cells. The optimized TD nanocarrier for monomeric AmB encapsulation significantly increases the therapeutic index, reduces the in vivo toxicity, and enhances antifungal effects in mouse models with Candida albicans infection in comparison to two common clinical formulations, i.e., Fungizone and AmBisome.

Influence of lung cancer model characteristics on tumor targeting behavior of nanodrugs

Evidence is mounting that there is a significant gap between the antitumor efficacy of nanodrugs in preclinical mouse tumor models and in clinical human tumors, and that differences in tumor models are likely to be responsible for this gap. Herein, we investigated the enhanced permeability and retention (EPR) effect in mouse lung cancer models with different tumor growth rates, volumes and locations, and analyzed the nanodrug tumor targeting behaviors limited by tumor vascular pathophysiological characteristics in various tumor models. The results showed that the fast-growing tumors were characterized by lower vascular tight junctions, leading to higher vascular paracellular transport activity and nanodrug tumor accumulation. The paracellular transport activity increased with the growth of tumor, but the vascular density and transcellular transport activity decreased, and as a result, the average tumor accumulation of passive targeting nanodrugs decreased. Orthotopic tumors were rich in blood vessels, but had low vascular transcellular and paracellular transport activities, making it difficult for nanodrug accumulation in orthotopic tumors via passive targeting strategies. The antitumor efficacy of passive targeting nanodrugs in various lung cancer-bearing mice validated the aforementioned nanodrug accumulation behavior, and nanodrugs based on the angiogenesis-tumor sequential targeting strategy achieved obviously improved efficacy in orthotopic lung cancer-bearing mice. These results suggest that the EPR effect varies in different tumor models and should not be used as a universal targeting strategy for antitumor nanodrugs. Besides, attention should be paid to the animal tumor models in the evaluation of nanodrugs so as to avoid exaggerating the antitumor efficacy.

Temperature-Responsive Nano-Biomaterials from Genetically Encoded Farnesylated Disordered Proteins

Despite broad interest in understanding the biological implications of protein farnesylation in regulating different facets of cell biology, the use of this post-translational modification to develop protein-based materials and therapies remains underexplored. The progress has been slow due to the lack of accessible methodologies to generate farnesylated proteins with broad physicochemical diversities rapidly. This limitation, in turn, has hindered the empirical elucidation of farnesylated proteins' sequence-structure-function rules. To address this gap, we genetically engineered prokaryotes to develop operationally simple, high-yield biosynthetic routes to produce farnesylated proteins and revealed determinants of their emergent material properties (nano-aggregation and phase-behavior) using scattering, calorimetry, and microscopy. These outcomes foster the development of farnesylated proteins as recombinant therapeutics or biomaterials with molecularly programmable assembly.

Tumor-Microenvironment-Activated NIR-II Nanotheranostic Platform for Precise Diagnosis and Treatment of Colon Cancer

Rational design of tumor-microenvironment (TME)-activated nanoformulation for precisely targeted cancer treatment has recently attracted an enormous attention. However, the all-in-one TME-activated theranostic nanosystems with a simple preparation and high biocompatibility are still rarely reported. Herein, catalase nanocrystals (CatCry) are first introduced as a tumor microenvironment activatable nanoplatform for selective theranostics of colon cancer. They are engaged as (i) a "nanoreactor" for silver nanoparticles (AgNP) synthesis, (ii) a nanovehicle for tumor delivery of anticancer drug doxorubicin (DOX), and (iii) an in situ O2 generator to relief tumor hypoxia. When CatCry-AgNP-DOX nanoformulation is within a tumor, the intratumoral H2S turns AgNP into Ag2S nanoparticles, inducing a photothermal effect and NIR-II emission under 808 nm laser irradiation and also triggering DOX release. Simultaneously, CatCry catalyzes intratumoral H2O2 into O2, relieving hypoxia and enhancing chemotherapy. In contrast, when delivered to healthy tissue without increased concentration of H2S, the developed nanoformulation remains in the "off" state and no theranostic action takes place. Studies with colon cancer cells in vitro and a murine colon cancer model in vivo demonstrated that CatCry-AgNP-DOX delivered a synergistic combination of PTT and enhanced chemotherapy, enabling complete eradication of tumor with minimal side effects. This work not only introduces nanoplatform for theranostics of H2S-rich tumors but also suggests a general strategy for protein-crystal-based nanomedicine.

Development of targeted micelles and polymersomes prepared from degradable RAFT-based diblock copolymers and their potential role as nanocarriers for chemotherapeutics

Modern polymerisation techniques allow synthesis of functional block copolymers that can self-assemble into degradable nanoparticles (NPs) of different sizes and conformations.

Peptide dendrimers as potentiators of conventional chemotherapy in the treatment of pancreatic cancer in a mouse model

Chemotherapy is the recommended treatment for patients with advanced pancreatic ductal adenocarcinoma (PDAC). However, efficacy of traditional chemotherapy is not satisfactory due to the presence of a dense dysplastic tumor stroma which prevents drug accumulation in and deep penetration into tumors. To overcome these obstacles, we designed and synthesized peptide dendrimers as potentiators of conventional chemotherapy. The dendrimers markedly promoted free doxorubicin accumulation and penetration deeply into 3D multicellular PDAC tumor cultures upon co-incubation. Co-administration of the dendrimer and doxorubicin into PDAC tumor xenograft-bearing mice greatly increased the doxorubicin concentration in the tumor. In addition, the dendrimer also promoted free doxorubicin internalization into PDAC cells upon co-incubation in media mimicking tumor microenvironment. Finally, a significant enhancement in the anticancer efficacy of doxorubicin and gemcitabine when either of the drugs was individually co-administered with the dendrimer into PDAC tumor xenograft-bearing mice was observed. This was especially pronounced for the combination treatment with the dendrimer and gemcitabine, resulting in a tumor weight decrease to 12.9% compared to the treatment with gemcitabine alone. This can be attributed to the combination of the multi-functionalities of the dendrimer, i.e., promoting free drug accumulation and penetration deeply into tumors and internalization into cancer cells.

Advances in Non-Animal Testing Approaches towards Accelerated Clinical Translation of Novel Nanotheranostic Therapeutics for Central Nervous System Disorders

Nanotheranostics constitute a novel drug delivery system approach to improving systemic, brain-targeted delivery of diagnostic imaging agents and pharmacological moieties in one rational carrier platform. While there have been notable successes in this field, currently, the clinical translation of such delivery systems for the treatment of neurological disorders has been limited by the inadequacy of correlating in vitro and in vivo data on blood-brain barrier (BBB) permeation and biocompatibility of nanomaterials. This review aims to identify the most contemporary non-invasive approaches for BBB crossing using nanotheranostics as a novel drug delivery strategy and current non-animal-based models for assessing the safety and efficiency of such formulations. This review will also address current and future directions of select in vitro models for reducing the cumbersome and laborious mandate for testing exclusively in animals. It is hoped these non-animal-based modelling approaches will facilitate researchers in optimising promising multifunctional nanocarriers with a view to accelerating clinical testing and authorisation applications. By rational design and appropriate selection of characterised and validated models, ranging from monolayer cell cultures to organ-on-chip microfluidics, promising nanotheranostic particles with modular and rational design can be screened in high-throughput models with robust predictive power. Thus, this article serves to highlight abbreviated research and development possibilities with clinical translational relevance for developing novel nanomaterial-based neuropharmaceuticals for therapy in CNS disorders. By generating predictive data for prospective nanomedicines using validated in vitro models for supporting clinical applications in lieu of requiring extensive use of in vivo animal models that have notable limitations, it is hoped that there will be a burgeoning in the nanotherapy of CNS disorders by virtue of accelerated lead identification through screening, optimisation through rational design for brain-targeted delivery across the BBB and clinical testing and approval using fewer animals. Additionally, by using models with tissue of human origin, reproducible therapeutically relevant nanomedicine delivery and individualised therapy can be realised.

Photoacoustic Properties of Polypyrrole Nanoparticles

Photoacoustic imaging, an emerging modality, provides supplemental information to ultrasound imaging. We investigated the properties of polypyrrole nanoparticles, which considerably enhance contrast in photoacoustic images, in relation to the synthesis procedure and to their size. We prepared polypyrrole nanoparticles by water-based redox precipitation polymerization in the presence of ammonium persulphate (ratio nPy:nOxi 1:0.5, 1:1, 1:2, 1:3, 1:5) or iron(III) chloride (nPy:nOxi 1:2.3) acting as an oxidant. To stabilize growing nanoparticles, non-ionic polyvinylpyrrolidone was used. The nanoparticles were characterized and tested as a photoacoustic contrast agent in vitro on an imaging platform combining ultrasound and photoacoustic imaging. High photoacoustic signals were obtained with lower ratios of the oxidant (nPy:nAPS ≥ 1:2), which corresponded to higher number of conjugated bonds in the polymer. The increasing portion of oxidized structures probably shifted the absorption spectra towards shorter wavelengths. A strong photoacoustic signal dependence on the nanoparticle size was revealed; the signal linearly increased with particle surface. Coated nanoparticles were also tested in vivo on a mouse model. To conclude, polypyrrole nanoparticles represent a promising contrast agent for photoacoustic imaging. Variations in the preparation result in varying photoacoustic properties related to their structure and allow to optimize the nanoparticles for in vivo imaging.

Facial Solid-Phase Synthesis of Well-Defined Zwitterionic Amphiphiles for Enhanced Anticancer Drug Delivery

Serum protein adsorption on the nanoparticle surface determines the biological identity of polymeric nanocarriers and critically impacts the in vivo stability following intravenous injection. Ultrahydrophilic surfaces are desired in delivery systems to reduce the serum protein corona formation, prolong drug pharmacokinetics, and improve the in vivo performance of nanotherapeutics. Zwitterionic polymers have been explored as alternative stealth materials for biomedical applications. In this study, we employed facial solid-phase peptide chemistry (SPPC) to synthesize multifunctional zwitterionic amphiphiles for application as a drug delivery vehicle. SPPC facilitates synthesis and purification of the well-defined dendritic amphiphiles, yielding high-purity and precise architecture. Zwitterionic glycerylphosphorylcholine (GPC) was selected as a surface moiety for the construction of a ultrahydrophilic dendron, which was coupled on solid phase to a hydrophobic dendron using multiple rhein (Rh) molecules as drug-binding moieties (DBMs) for doxorubicin (DOX) loading via pi-pi stacking and hydrogen bonding. The resulting zwitterionic amphiphilic Janus dendrimer (denoted as GPC₈-Rh₄) showed improved stabilities and sustained drug release compared to the analogue with poly(ethylene glycol) (PEG) surface (PEG^5k-Rh₄). In vivo studies in xenograft mouse tumor models demonstrated that the DOX-GPC₈-Rh₄ nanoformulation significantly improved anticancer effects compared to DOX-PEG^5k-Rh₄, owing to the improved in vivo pharmacokinetics and increased tumor accumulation.