Surface modification of lipid nanoparticles for gene therapy.

Gene therapies have the potential to target and effectively treat a variety of diseases including cancer as well as genetic, neurological, and autoimmune disorders. Although we have made significant advances in identifying non-viral strategies to deliver genetic cargo, certain limitations remain. In general, gene delivery is challenging for several reasons including the instabilities of nucleic acids to enzymatic and chemical degradation and the presence of restrictive biological barriers such as cell, endosomal and nuclear membranes. The emergence of lipid nanoparticles (LNPs) helped overcome many of these challenges. Despite its success, further optimization is required for LNPs to yield efficient gene delivery to extrahepatic tissues, as LNPs favor accumulation in the liver after systemic administration. In this mini-review, we provide an overview of current preclinical approaches in that LNP surface modification was leveraged for cell and tissue targeting by conjugating aptamers, antibodies, and peptides among others. In addition to their cell uptake and efficiency-enhancing effects, we outline the (dis-)advantages of the different targeting moieties and commonly used conjugation strategies.

Cyanine- and Rhodamine-Derived Alkynes for the Selective Targeting of Cancerous Mitochondria through Radical Thiol-Yne Coupling in Live Cells.

Despite their long history and their synthetic potential underlined by various recent advances, radical thiol-yne coupling reactions have so far only rarely been exploited for the functionalization of biomolecules, and no examples yet exist for their application in live cells - although natural thiols show widespread occurrence therein. By taking advantage of the particular cellular conditions of mitochondria in cancer cells, we have demonstrated that radical thiol-yne coupling represents a powerful reaction principle for the selective targeting of these organelles. Within our studies, fluorescently labeled reactive alkyne probes were investigated, for which the fluorescent moiety was chosen to enable both mitochondria accumulation as well as highly sensitive detection. After preliminary studies under cell-free conditions, the most promising alkyne-dye conjugates were evaluated in various cellular experiments comprising analysis by flow cytometry and microscopy. All in all, these results pave the way for improved future therapeutic strategies relying on live-cell compatibility and selectivity among cellular compartments.

Functionalization of curcumin nanomedicines: a recent promising adaptation to maximize pharmacokinetic profile, specific cell internalization and anticancer efficacy against breast cancer.

Owing to its diverse heterogeneity, aggressive nature, enormous metastatic potential, and high remission rate, the breast cancer (BC) is among the most prevalent types of cancer associated with high mortality. Curcumin (Cur) is a potent phytoconstituent that has gained remarkable recognition due to exceptional biomedical viability against a wide range of ailments including the BC. Despite exhibiting a strong anticancer potential, the clinical translation of Cur is restricted due to intrinsic physicochemical properties such as low aqueous solubility, chemical instability, low bioavailability, and short plasma half-life. To overcome these shortcomings, nanotechnology-aided developments have been extensively deployed. The implication of nanotechnology has pointedly improved the physicochemical properties, pharmacokinetic profile, cell internalization, and anticancer efficacy of Cur; however, majority of Cur-nanomedicines are still facing grandeur challenges. The advent of various functionalization strategies such as PEGylation, surface decoration with different moieties, stimuli-responsiveness (i.e., pH, light, temperature, heat, etc.), tethering of specific targeting ligand(s) based on the biochemical targets (e.g., folic acid receptors, transferrin receptors, CD44, etc.), and multifunctionalization (multiple functionalities) has revolutionized the fate of Cur-nanomedicines. This study ponders the biomedical significance of various Cur-nanomedicines and adaptable functionalizations for amplifying the physicochemical properties, cytotoxicity via induction of apoptosis, cell internalization, bioavailability, passive and active targeting to the tumor microenvironment (TME), and anticancer efficacy of the Cur while reversing the multidrug resistance (MDR) and reoccurrence in BC. Nevertheless, the therapeutic outcomes of Cur-nanomedicines against the BC have been remarkably improved after adaptation of various functionalizations; however, this evolving strategy still demands extensive research for scalable clinical translation.

Development of Novel Pt(IV)-Carbohydrate Derivatives as Targeted Anticancer Agents against Osteosarcoma.

Despite the enormous importance of cisplatin as a chemotherapeutic agent, its application is impacted by dose-limiting side effects and lack of selectivity for cancer cells. Researchers can overcome these issues by taking advantage of the pro-drug nature of the platinum(IV) oxidation state, and by modifying the coordination sphere of the metal centre with specific vectors whose receptors are overexpressed in tumour cell membranes (e.g., carbohydrates). In this paper we report the synthesis of four novel carbohydrate-modified Pt(IV) pro-drugs, based on the cisplatin scaffold, and their biological activity against osteosarcoma (OS), a malignant tumour which is most common in adolescents and young adults. The carbohydrate-targeting vectors and Pt scaffold are linked using copper-catalysed azide-alkyne cycloaddition (CuAAC) chemistry, which is synonymous with mild and robust reaction conditions. The novel complexes are characterised using multinuclear 1D-2D NMR (1H, 13C and 195Pt), IR, HR-MS, Elem. Analyses, and CV. Cytotoxicity on 2D and 3D and cell morphology studies on OS cell lines, as well as non-cancerous human foetal osteoblasts (hFOBs), are discussed.

Selective Integrin α5ß1 Targeting through Spatially Constrained Multivalent DNA-Based Nanoparticles.

Targeting cells specifically based on receptor expression levels remains an area of active research to date. Selective binding of receptors cannot be achieved by increasing the individual binding strength, as this does not account for differing distributions of receptor density across healthy and diseased cells. Engaging receptors above a threshold concentration would be desirable in devising selective diagnostics. Integrins are prime target candidates as they are readily available on the cell surface and have been reported to be overexpressed in diseases. Insights into their spatial organization would therefore be advantageous to design selective targeting agents. Here, we investigated the effect of activation method on integrin α5ß1 clustering by immunofluorescence and modeled the global neighbor distances with input from an immuno-staining assay and image processing of microscopy images. This data was used to engineer spatially-controlled DNA-scaffolded bivalent ligands, which we used to compare trends in spatial-selective binding observed across HUVEC, CHO and HeLa in resting versus activated conditions in confocal microscopy images. For HUVEC and CHO, the data demonstrated an improved selectivity and localisation of binding for smaller spacings ~7 nm and ~24 nm, in good agreement with the model. A deviation from the mode predictions for HeLa was observed, indicative of a clustered, instead of homogeneous, integrin organization. Our findings demonstrate how low-technology imaging methods can guide the design of spatially controlled ligands to selectively differentiate between cell type and integrin activation state.

Nanotechnology applications for cardiovascular disease treatment: Current and future perspectives.

A large majority of cardiovascular nanomedicine research has focused on fabricating designer nanoparticles for improved targeting as a means to overcome biological barriers. For cardiac related disorders, such as atherosclerosis, hypertension, and myocardial infarction, designer micro or nanoparticles are often administered into the vasculature or targeted vessel with the hope to circumvent problems associated with conventional drug delivery, including negative systemic side effects. Additionally, novel nano-drug carriers that enter circulation can be selectively uptaken by immune cells with the intended purpose that they modulate inflammatory processes and migrate locally to plaque for therapeutic payload delivery. Indeed, innovative design in nanoparticle composition, formulation, and functionalization has advanced the field as a means to achieve therapeutic efficacy for a variety of cardiac disease indications. This perspective aims to discuss these advances and provide new interpretations of how nanotechnology can be best applied to aid in cardiovascular disease treatment. In an effort to spark discussions on where the field of research should go, we share our outlook in new areas of nanotechnological inclusion and integration, such as in vascular, implantable, or wearable device technologies as well as nanocomposites and nanocoatings. Further, as cardiovascular diseases (CVD) increasingly claim a number of lives globally, we propose more attention should be placed by researchers on nanotechnological approaches for risk factor treatment to aid in early prevention and treatment of CVD.

Black Phosphorus-Based Multimodal Nanoagent: Showing Targeted Combinatory Therapeutics against Cancer Metastasis.

In breast cancer chemophotothermal therapy, it is a great challenge for the development of multifunctional nanoagents for precision targeting and the effective treatment of tumors, especially for metastasis. Herein, we successfully design and synthesize a multifunctional black phosphorus (BP)-based nanoagent, BP/DTX@PLGA, to address this challenge. In this composite nanoagent, BP quantum dots (BPQDs) are loaded into poly(lactic-co-glycolic acid) (PLGA) with additional conjugation of a chemotherapeutic agent, docetaxel (DTX). The in vivo distribution results demonstrate that BP/DTX@PLGA shows striking tropism for targeting both primary tumors and lung metastatic tumors. Moreover, BP/DTX@PLGA exhibits outstanding controllable chemophotothermal combinatory therapeutics, which dramatically improves the efficacy of photothermal tumor ablation when combined with near-light irradiation. Mechanistically, accelerated DTX release from the nanocomplex upon heating and thermal treatment per se synergistically incurs apoptosis-dependent cell death, resulting in the elimination of lung metastasis. Meanwhile, in vitro and in vivo results further confirm that BP/DTX@PLGA possesses good biocompatibility. This study provides a promising BP-based multimodal nanoagent to constrain cancer metastasis.

Tumor mechanosensing and its therapeutic potential.

Cancer mechanics have lately emerged as a distinct tumor feature that promotes tumor development, invasion, and metastasis. Tumor mechanosensing involves a mechanical interplay between cancer cells, extracellular matrix, and cells of the surrounding stroma. Mechanoreceptors sense alterations of the extracellular mechanical cues and activate signaling molecules, which mediate oncogenic transcription in favor of cancer initiation, survival, growth, and metastasis. Furthermore, alterations of the matrix rigidity and activation of mechano-induced transcriptional regulators has been strongly associated with resistance to anti-cancer agents. In this context, new mechanosensitive molecules arise as potential therapeutic targets. Therefore, tumor mechanosignaling represents a promising field that can potentially offer new combination regimens to overcome drug resistance, but also suggest novel targeting strategies.

Selective targeting and degradation of doxorubicin-loaded folate-functionalized DNA nanocages.

Selective targeting is a crucial property of nanocarriers used for drug delivery in cancer therapy. We generated biotinylated octahedral DNA nanocages functionalized with folic acid through bio-orthogonal conjugation chemistry. Molecular modelling indicated that a distance of about 2.5 nm between folic acid and DNA nanocage avoids steric hindrance with the folate receptor. HeLa cells, a folate receptor positive tumour cell line, internalize folate-DNA nanocages with efficiency greater than 40 times compared to cells not expressing the folate receptors. Functionalized DNA nanocages are highly stable, not cytotoxic and can be efficiently loaded with the chemotherapeutic agent doxorubicin. After entry into cells, doxorubicin-loaded nanoparticles are confined in vesicular structures, indicating that DNA nanocages traffic through the endocytic pathway. Doxorubicin release from loaded DNA cages, facilitated by low pH of endocytic vesicles, induces toxic pathways that, besides selectively killing folate receptor-positive cancer cells, leads to cage degradation avoiding nanoparticles accumulation inside cells.

Targeting lipodisks enable selective delivery of anticancer peptides to tumor cells.

Issues concerning non-specificity, degradation and hemolysis severely hamper the development of membranolytic amphiphilic peptides into safe and efficient anticancer agents. To increase the therapeutic potential, we have previously developed a strategy based on formulation of the peptides in biocompatible nanosized lipodisks. Studies using melittin as model peptide show that the proteolytic degradation and hemolytic effect of the peptide are substantially reduced upon loading in lipodisks. Here, we explored the possibilities to increase the specificity and boost the cytotoxicity of melittin to tumor cells by use of targeting lipodisk. We demonstrate that small (~20 nm) EGF-targeted lipodisks can be produced and loaded with substantial amounts of peptide (lipid/peptide molar ratio >7) by means of a simple and straightforward preparation protocol. In vitro cell studies confirm specific binding of the peptide-loaded disks to tumor cells and suggest that cellular internalization of the disks results in a significantly improved cell-killing effect.

Mesoporous Silica Nanoparticles for Drug Delivery: Current Insights.

This manuscript reviews the recent progress on mesoporous silica nanoparticles as drug delivery systems. Their intrinsic structural, textural and chemical features permit to design versatile multifunctional nanosystems with the capability to target the diseased tissue and release the cargo on demand upon exposition to internal or external stimuli. The degradation rate of these nanocarriers in diverse physiological fluids is overviewed obeying their significance for their potential translation towards clinical applications. To conclude, the balance between the benefits and downsides of this revolutionary nanotechnological tool is also discussed.

Nanomedicines: Emerging Platforms in Smart Chemotherapy Treatment-A Recent Review.

Cancer continues to pose one of the most critical challenges in global healthcare. Despite the wide array of existing cancer drugs, the primary obstacle remains in selectively targeting and eliminating cancer cells while minimizing damage to healthy ones, thereby reducing treatment side effects. The revolutionary approach of utilizing nanomaterials for delivering cancer therapeutic agents has significantly enhanced the efficacy and safety of chemotherapeutic drugs. This crucial shift is attributed to the unique properties of nanomaterials, enabling nanocarriers to transport therapeutic agents to tumor sites in both passive and active modes, while minimizing drug elimination from delivery systems. Furthermore, these nanocarriers can be designed to respond to internal or external stimuli, thus facilitating controlled drug release. However, the production of nanomedications for cancer therapy encounters various challenges that can impede progress in this field. This review aims to provide a comprehensive overview of the current state of nanomedication in cancer treatment. It explores a variety of nanomaterials, focusing on their unique properties that are crucial for overcoming the limitations of conventional chemotherapy. Additionally, the review delves into the properties and functionalities of nanocarriers, highlighting their significant impact on the evolution of nanomedicine. It also critically assesses recent advancements in drug delivery systems, covering a range of innovative delivery methodologies. Finally, the review succinctly addresses the challenges encountered in developing nanomedications, offering insightful perspectives to guide future research in this field.

Bioinspired extracellular vesicle-coated silica nanoparticles as selective delivery systems.

In recent years, there has been a breakthrough in the integration of artificial nanoplatforms with natural biomaterials for the development of more efficient drug delivery systems. The formulation of bioinspired nanosystems, combining the benefits of synthetic nanoparticles with the natural features of biological materials, provides an efficient strategy to improve nanoparticle circulation time, biocompatibility and specificity toward targeted tissues. Among others biological materials, extracellular vesicles (EVs), membranous structures secreted by many types of cells composed by a protein rich lipid bilayer, have shown a great potential as drug delivery systems themselves and in combination with artificial nanoparticles. The reason for such interest relays on their natural properties, such as overcoming several biological barriers or migration towards specific tissues. Here, we propose the use of mesoporous silica nanoparticles (MSNs) as efficient and versatile nanocarriers in combination with tumor derived extracellular vesicles (EVs) for the development of selective drug delivery systems. The hybrid nanosystems demonstrated selective cellular internalization in parent cells, indicating that the EV targeting capabilities were efficiently transferred to MSNs by the developed coating strategy. As a result, EVs-coated MSNs provided an enhanced and selective intracellular accumulation of doxorubicin and a specific cytotoxic activity against targeted cancer cells, revealing these hybrid nanosystems as promising candidates for the development of targeted treatments.

Highly Selective Targeting of Pancreatic Cancer in the Liver with a Near-Infrared Anti-MUC5AC Probe in a PDOX Mouse Model: A Proof-of-Concept Study.

Accurately identifying metastatic disease is critical to directing the appropriate treatment in pancreatic cancer. Mucin 5AC is overexpressed in pancreatic cancer but absent in normal pancreas tissue. The present proof-of-concept study demonstrates the efficacy of an anti-mucin 5AC antibody conjugated to an IR800 dye (MUC5AC-IR800) to preferentially label a liver metastasis of pancreatic cancer (Panc Met) in a unique patient-derived orthotopic xenograft (PDOX) model. In orthotopic models, the mean tumor to background ratio was 1.787 (SD ± 0.336), and immunohistochemistry confirmed the expression of MUC5AC within tumor cells. MUC5AC-IR800 provides distinct visualization of pancreatic cancer liver metastasis in a PDOX mouse model, demonstrating its potential utility in staging laparoscopy and fluorescence-guided surgery.

Brain-wide circuit-specific targeting of astrocytes.

Astrocytes are integral components of brain circuitry. They enwrap synapses, react to neuronal activity, and regulate synaptic transmission. Astrocytes are heterogeneous and exhibit distinct features and functions in different circuits. Selectively targeting the astrocytes associated with a given neuronal circuit would enable elucidation of their circuit-specific functions but has been technically challenging to date. Recently, we constructed anterograde transneuronal viral vectors based on yellow fever vaccine YFV-17D. Among them, the replication-incompetent YFVΔNS1-Cre can selectively turn on reporter genes in postsynaptic neurons if the viral gene NS1 is expressed in postsynaptic neurons. Here we show that without exogenous expression of NS1 at the postsynaptic sites, locally injected YFVΔNS1-Cre selectively turns on reporter genes in astrocytes in downstream brain regions. The targeting of astrocytes can occur across the whole brain but is specific for the neuronal circuits traced. Therefore, YFVΔNS1-Cre provides a tool for selective genetic targeting of astrocytes to reveal their circuit-specific roles.

Protein-imprinted polymers: How far have "plastic antibodies" come?

Antibodies are highly selective and sensitive, making them the gold standard for recognition affinity tools. However, their production cost is high and their downstream processing is time-consuming. Molecularly imprinted polymers (MIPs) are tailor-made by incorporating specific molecular recognition sites in their structure, thus translating into receptor-like activity mode of action. The interest in molecular imprinting technology, applied to biomacromolecules, has increased in the past decade. MIPs, produced using biomolecules as templates, commonly referred to as "plastic antibodies" or "artificial receptors", have been considered as suitable cheaper and easy to produce alternatives to antibodies. Research on MIPs, designed to recognize proteins or peptides is particularly important, with potential contributions towards biomedical applications, namely biosensors and targeted drug delivery systems. This mini review will cover recent advances on (bio)molecular imprinting technology, where proteins or peptides are targeted or mimicked for sensing and therapeutic applications. Polymerization methods are reviewed elsewhere, being out of the scope of this review. Template selection and immobilization approaches, monomers and applications will be discussed, highlighting possible drawbacks and gaps in research.

Full-Length Transcript Phasing with Third-Generation Sequencing.

Haplotyping individual full-length transcripts can be important in diagnosis and treatment of certain genetic diseases. One set of diseases, repeat expansions of simple tandem repeat sequences are the cause of over 40 neurological disorders. In many of these conditions, expanding a polymorphic repeat beyond a given threshold has been strongly associated with disease onset and severity. Given that most repeat expansions are inherited in an autosomal dominant pattern, repeat expansion disorders are typically characterized by a heterozygous expansion locus associated with a single haplotype. Precision genetic medicines can be used to selectively target expansion-containing sequences in a haplotype-specific manner.However, repeat expansion lengths often exceed the capacity of next-generation sequencing (NGS) reads. Therefore, the accurate length and haplotype determination of repeat expansions requires special considerations and requires the development of custom methods. Here we highlight a method for targeted haplotype phasing of the HTT gene, which can be adopted for use with other full-length transcripts and in other repeat expansion disorders.

CRISPR-Cas9 for selective targeting of somatic mutations in pancreatic cancers.

Somatic mutations are desirable targets for selective elimination of cancer, yet most are found within the noncoding regions. We propose a novel, cancer-specific killing approach using CRISPR-Cas9 which exploits the requirement of a protospacer adjacent motif (PAM) for Cas9 activity. Through whole genome sequencing (WGS) of paired tumor minus normal (T-N) samples from three pancreatic cancer patients (Panc480, Panc504, and Panc1002), we identified an average of 417 somatic PAMs per tumor produced from single base substitutions. We analyzed 591 paired T-N samples from The International Cancer Genome Consortium and discovered medians of ~455 somatic PAMs per tumor in pancreatic, ~2800 in lung, and ~3200 in esophageal cancer cohorts. Finally, we demonstrated >80% selective cell death of two targeted pancreatic cancer cell lines in co-cultures using 4-9 sgRNAs, targeting noncoding regions, designed from the somatic PAM discovery approach. We also showed no off-target activity from these tumor-specific sgRNAs through WGS.

Radiolabeled Iron Oxide Nanoparticles as Dual Modality Contrast Agents in SPECT/MRI and PET/MRI.

During the last decades, the utilization of imaging modalities such as single photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI) in every day clinical practice has enabled clinicians to diagnose diseases accurately at early stages. Radiolabeled iron oxide nanoparticles (RIONs) combine their intrinsic magnetic behavior with the extrinsic character of the radionuclide additive, so that they constitute a platform of multifaceted physical properties. Thus, at a practical level, RIONs serve as the physical parent of the so-called dual-modality contrast agents (DMCAs) utilized in SPECT/MRI and PET/MRI applications due to their ability to combine, at real time, the high sensitivity of SPECT or PET together with the high spatial resolution of MRI. This review focuses on the synthesis and in vivo investigation of both biodistribution and imaging efficacy of RIONs as potential SPECT/MRI or PET/MRI DMCAs.

Present and future of microglial pharmacology.

Microglia, brain resident immune cells, modulate development, activity, and plasticity of the central nervous system. Mechanistically implicated in numerous neurological pathologies, microglia emerge as strong contenders for novel neurotherapies. Shifting away from merely an attenuation of excessive microglial inflammatory and phagocytic activities, current therapies aim toward targeting the complex context-dependent microglial heterogeneity, unveiled by large-scale genetic studies and emerging single-cell analyses. Although lacking the necessary selectivity, initial therapies attempting to target specific state-associated microglial properties and functions (e.g., inflammatory activity, phagocytosis, proliferation, metabolism, or surveillance) are currently under pre- or even clinical (Phase I-IV) investigation. Here, we provide an update on current microglial therapeutic research and discuss what the future in the field might look like.