Functionalized nanoparticles with targeted antibody to enhance imaging of breast cancer in vivo

Recent emerging trends in dendrimer research: Electrochemical sensors and their multifaceted applications in biomedical fields or healthcare

Dendrimers enhance the selectivity and sensitivity of sensors through their synthetic, highly branched, three-dimensional structures and large surface area. This unique architecture enables precise functionalization with various recognition elements, significantly improving the specificity and sensitivity of electrochemical sensors for detecting disease markers, biomolecules, and environmental pollutants. Dendrimer-based electrochemical sensors offer promising advancements in healthcare, such as detecting biomarkers for heart disease, monitoring blood glucose levels, and sensitively determining cancer-related proteins. Additionally, incorporating metals and conductive polymers into dendrimer nanocomposites can further enhance sensor performance. This review article provides a detailed overview of dendrimer's history, structure, properties, electrochemical properties, and synthesis methods. Particular attention has been paid to recent developments in the applications of dendrimers including electrochemical sensors, drug delivery, gene therapy and bioimaging. Recent progress in various applications of dendrimer-based electrochemical sensors developed over the last seven years, focusing on their healthcare applications and discussing the primary goals and challenges that will shape future research in this field, is also critically analyzed. These advances in dendrimer technology hold great potential for the development of novel therapeutics and expanded applications in sensor design.

JR, Xu Z, Wang S. Ultrasound-Guided Histotripsy Triggers the Release of Tumor-Associated Antigens from Breast Cancers

Background/Objectives: There is increasing evidence to indicate that histotripsy treatment can enhance the host anti-tumor immune responses both locally at the targeting tumor site as well as systemically from abscopal effects. Histotripsy is a non-invasive ultrasound ablation technology that mechanically disrupts target tissue via cavitation. A key factor contributing to histotripsy-induced abscopal effects is believed to be the release of tumor-specific antigens (TSAs) or tumor-associated antigens (TAAs) that induce a systemic immune response. In this study, we studied the effect of histotripsy treatment on the release of HER2, a well-defined TAA target for cancer immunotherapy. Methods: A range of doses of histotripsy administered to HER2-postive mammary tumor cells in an in vitro cell culture system and an ex vivo tumor were applied. In addition, a single dose of histotripsy was used for an in vivo murine tumor model. The released proteins, and specifically HER2, in both tumor cell-free supernatants and tumor cell pellets were analyzed by a BCA protein assay, an ultra-performance liquid chromatography (UPLC) assay, and Western blot. Results: Our results showed that histotripsy could significantly trigger the release of HER2 proteins in the current study. The level of HER2 proteins was actually higher in tumor cell-free supernatants than in tumor cell pellets, suggesting that HER2 was released from the intracellular domain into the extracellular compartment. Furthermore, proportionally more HER2 protein was released at higher histotripsy doses, indicating free HER2 was histotripsy-dose-dependent. Conclusions: In conclusion, we have qualitatively and quantitatively demonstrated that histotripsy treatment triggers the release of HER2 from the tumor cells into the extracellular compartment. The histotripsy-mediated release of HER2 antigens provides important insights into the mechanism underlying its immunostimulation and suggests the potential of TSA/TAA-based immunotherapies in numerous cancer types.

Advances in Dendritic Systems and Dendronized Nanoparticles: Paradigm Shifts in Cancer Targeted Therapy and Diagnostics

Cancer has emerged as a global health crisis, claiming millions of lives annually. Dendrimers and dendronized nanoparticles, a novel class of nanoscale molecules with highly branched three-dimensional macromolecular structures, have gained significant attention in cancer treatment and diagnosis due to their unique properties. These dendritic macromolecules offer a precisely controlled branching architecture, enabling functionalization with specific targeting molecules to enhance the selective delivery of therapeutic agents to tumor cells while minimizing systemic toxicity. Through surface modifications and the incorporation of various components, dendrimers demonstrate remarkable adaptability as nanocarriers for biomedical imaging and theranostic applications. Surface functionalization strategies, including PEGylation and ligand attachment (e.g., folic acid, RGD peptide, lactobionic acid), further enhance biocompatibility and facilitate targeted tumor cell imaging. Leveraging their improved biocompatibility and target specificity, dendritic nanosystems offer heightened sensitivity and precision in cancer diagnostics. Notably, the encapsulation of metal nanoparticles within dendrimers, such as gold nanoparticles, has shown promise in enhancing tumor imaging capabilities. Ongoing advancements in nanotechnology are poised to increase the sophistication and complexity of dendrimer-based systems, highlighting their potential as nanocarriers in drug delivery platforms, with a growing number of clinical trials on the horizon. This review provides a comprehensive overview of the potential and future prospects of dendrimers and dendrimer-based nanocarriers in targeted cancer therapy and diagnosis, exploring their ability to enhance biocompatibility, reduce toxicity, and improve therapeutic outcomes across various malignancies.

A review on dendrimer-based nanoconjugates and their intracellular trafficking in cancer photodynamic therapy

Nanotechnology-based cancer treatment has received considerable attention, and these treatments generally use drug-loaded nanoparticles (NPs) to target and destroy cancer cells. Nanotechnology combined with photodynamic therapy (PDT) has demonstrated positive outcomes in cancer therapy. Combining nanotechnology and PDT is effective in targeting metastatic cancer cells. Nanotechnology can also increase the effectiveness of PDT by targeting cells at a molecular level. Dendrimer-based nanoconjugates (DBNs) are highly stable and biocompatible, making them suitable for drug delivery applications. Moreover, the hyperbranched structures in DBNs have the capacity to load hydrophobic compounds, such as photosensitizers (PSs) and chemotherapy drugs, and deliver them efficiently to tumour cells. This review primarily focuses on DBNs and their potential applications in cancer treatment. We discuss the chemical design, mechanism of action, and targeting efficiency of DBNs in tumour metastasis, intracellular trafficking in cancer treatment, and DBNs' biocompatibility, biodegradability and clearance properties. Overall, this study will provide the most recent insights into the application of DBNs and PDT in cancer therapy.

Albumin incorporation into recognising layer of HER2-specific magnetic nanoparticles as a tool for optimal targeting of the acidic tumor microenvironment

Cancer is unquestionably a global healthcare challenge, spurring the exporation of novel treatment approaches. In recent years, nanomaterials have garnered significant interest with the greatest hopes for targeted nanoformulations due to their cell-specific delivery, improved therapeutic efficacy, and reduced systemic toxicity for the organism. The problem of successful clinical translation of nanoparticles may be related to the fact that most in vitro tests are performed at pH values of normal cells and tissues, ranging from 7.2 to 7.4. The extracellular pH values of tumors are characterized by a shift to a more acidic region in the range of 5.6-7.0 and represent a crucial target for enhancing nanoparticle delivery to cancer cells. Here we show the method of non-active protein incorporation into the surface of HER2-targeted nanoparticles to achieve optimal cellular uptake within the pH range of the tumor microenvironment. The method efficacy was confirmed in vitro and in vivo showing the maximum binding of nanoparticles to cells at a pH value 6.4. Namely, fluorescent magnetic nanoparticles, modified with HER2-recognising affibody ZHER2:342, with proven specificity in terms of HER2 recognition (with 62-fold higher cellular uptake compared to control nanoparticles) were designed for targeting cancer cells at slightly acidic pH values. The stabilizing protein, namely, bovine serum albumin, one of the major blood components with widespread availability and biocompatibility, was used for the decoration of the nanoparticle surface to alter the pH response of the targeting magnetic conjugates. The optimally designed nanoparticles showed a bell-shaped dependency of interaction with cancer cells in the pH range of 5.6-8.0 with maximum cellular uptake at pH value 6.4 close to that of the tumor microenvironment. In vivo experiments revealed that after i.v. administration, BSA-decorated nanoparticles exhibited 2 times higher accumulation in tumors compared to magnetic nanoparticles modified with affibody only. Thus, we demonstrated a valid method for enhancing the specificity of targeted nanoparticle delivery to cancer cells without changing the functional components of nanoparticles.

In Vivo Applications of Dendrimers: A Step toward the Future of Nanoparticle-Mediated Therapeutics

Over the last few years, the development of nanotechnology has allowed for the synthesis of many different nanostructures with controlled sizes, shapes, and chemical properties, with dendrimers being the best-characterized of them. In this review, we present a succinct view of the structure and the synthetic procedures used for dendrimer synthesis, as well as the cellular uptake mechanisms used by these nanoparticles to gain access to the cell. In addition, the manuscript reviews the reported in vivo applications of dendrimers as drug carriers for drugs used in the treatment of cancer, neurodegenerative diseases, infections, and ocular diseases. The dendrimer-based formulations that have reached different phases of clinical trials, including safety and pharmacokinetic studies, or as delivery agents for therapeutic compounds are also presented. The continuous development of nanotechnology which makes it possible to produce increasingly sophisticated and complex dendrimers indicates that this fascinating family of nanoparticles has a wide potential in the pharmaceutical industry, especially for applications in drug delivery systems, and that the number of dendrimer-based compounds entering clinical trials will markedly increase during the coming years.

Magnetic Particle Imaging-Guided Hyperthermia for Precise Treatment of Cancer: Review, Challenges, and Prospects

Magnetic particle imaging (MPI) is a novel quantitative imaging technique using the nonlinear magnetization behavior of magnetic nanoparticles (MNPs) to determine their local concentration. Magnetic fluid hyperthermia (MFH) is a promising non-invasive therapy using the heating effects of MNPs. MPI-MFH is expected to enable real-time MPI guidance, localized MFH, and non-invasive temperature monitoring, which shows great potential for precise treatment of cancer. In this review, we introduce the fundamentals of MPI and MFH and their applications in the treatment of cancer. Also, we discuss the challenges and prospects of MPI-MFH.

Non-invasive Diagnosis and Postoperative Evaluation of Carotid Artery Stenosis by BSA-Gd2O3 Nanoparticles-Based Magnetic Resonance Angiography

Contrast-enhanced magnetic resonance angiography is a powerful and effective method to accurately diagnose carotid artery stenosis. Small molecular gadolinium (Gd)-based agents have reliable signal enhancement, but their short circulating time may result in a loss of image resolution due to insufficient vascular filling or contrast agent emptying. Here, we report an MRA imaging approach to diagnose carotid artery stenosis using long-circulating bovine serum albumin (BSA)-Gd2O3 nanoparticles (NPs). The BSA-Gd2O3 NPs synthesized by a simple biomineralization approach exhibit admirable monodispersity, uniform size, favorable aqueous solubility, good biocompatibility, and high relaxivity (14.86 mM-1 s-1 in water, 6.41 mM-1 s-1 in plasma). In vivo MRA imaging shows that outstanding vascular enhancement of BSA-Gd2O3 NPs (0.05 mmol Gd/kg, half the dose in the clinic) can be maintained for at least 2 h, much longer than Gd-DTPA. Vessels as small as 0.3 mm can be clearly observed in MRA images with high resolution. In a rat carotid artery stenosis model, the BSA-Gd2O3 NPs-based MRA enables the precise diagnosis of the severity and location and the therapeutic effect following the surgery of carotid artery stenosis, which provides a method for the theranostics of vascular diseases.

CT and X-ray contrast agents: Current clinical challenges and the future of contrast

Computed tomography (CT) is a powerful and widely used imaging technique in modern medicine. However, it often requires the use of contrast agents to visualize structures with similar radiographic density. Unfortunately, current clinical contrast agents (CAs) for CT have remained largely unchanged for decades and come with several significant drawbacks, including serious nephrotoxicity and short circulation half-lives. The next generation of CT radiocontrast agents should strive to be long-circulating, non-toxic, and non-immunogenic. Nanoparticle contrast agents have shown promise in recent years and are likely to comprise the majority of next-generation CT contrast agents. This review highlights the fundamental mechanism and background of X-ray and contrast agents. It also focuses on the challenges associated with current clinical contrast agents and provides a brief overview of potential future agents that are based on various materials such as lipids, polymers, dendrimers, metallic, and non-metallic inorganic nanoparticles (NPs). STATEMENT OF SIGNIFICANCE: We realized a need for clarification on a number of concerns related to the use of iodinated contrast material as debates regarding the safety of these agents with patients with kidney disease, shellfish allergies, and thyroid dysfunction remain ongoing in medical practice. This review was partially inspired by debates witnessed in medical practice regarding outdated misconceptions of contrast material that warrant clarification in translational and clinical arenas. Given that conversation around currently available agents is at somewhat of a high water mark, and nanoparticle research has now reached an unprecedented number of readers, we find that this review is timely and unique in the context of recent discussions in the field.

Study of Gold Nanoparticles Conjugated with SARS-CoV-2 S1 Spike Protein Fragments

This study reports on the successful conjugation of SARS-CoV-2 S1 spike protein fragments with gold nanoparticles (AuNPs) that were synthesised with Ultrasonic Spray Pyrolysis (USP). This method enables the continuous synthesis of AuNPs with a high degree of purity, round shapes, and the formation of a surface that allows various modifications. The conjugation mechanism of USP synthesized AuNPs with SARS-CoV-2 S1 spike protein fragments was investigated. A gel electrophoresis experiment confirmed the successful conjugation of AuNPs with SARS-CoV-2 S1 fragments indirectly. X-ray Photoelectron Spectroscopy (XPS) analysis confirmed the presence of characteristic O1s and N1s peaks, which indicated that specific binding between AuNPs and SARS-CoV-2 S1 spike protein fragments takes place via a peptide bond formed with the citrate stabiliser. This bond is coordinated to the AuNP's surface and the N-terminals of the protein, with the conjugate displaying the expected response within a prototype LFIA test. This study will help in better understanding the behaviour of AuNPs synthesised with USP and their potential use as sensors in colorimetric or electrochemical sensors and LFIA tests.

Cancer Treatment Using Different Shapes of Gold-Based Nanomaterials in Combination with Conventional Physical Techniques

The conventional methods of cancer treatment and diagnosis, such as radiotherapy, chemotherapy, and computed tomography, have developed a great deal. However, the effectiveness of such methods is limited to the possible failure or collateral effects on the patients. In recent years, nanoscale materials have been studied in the field of medical physics to develop increasingly efficient methods to treat diseases. Gold nanoparticles (AuNPs), thanks to their unique physicochemical and optical properties, were introduced to medicine to promote highly effective treatments. Several studies have confirmed the advantages of AuNPs such as their biocompatibility and the possibility to tune their shapes and sizes or modify their surfaces using different chemical compounds. In this review, the main properties of AuNPs are analyzed, with particular focus on star-shaped AuNPs. In addition, the main methods of tumor treatment and diagnosis involving AuNPs are reviewed.

Recent advances in PAMAM dendrimer-based CT contrast agents for molecular imaging and theranostics of cancer

Recent advances and some key developments in the construction of PAMAM dendrimer-based nanoplatforms for tumor CT imaging and theranostics have been reviewed.

The role of imaging in targeted delivery of nanomedicine for cancer therapy

Nanomedicines overcome the pharmacokinetic limitations of traditional drug formulations and have promising prospect in cancer treatment. However, nanomedicine delivery in vivo is still facing challenges from the complex physiological environment. For the purpose of effective tumor therapy, they should be designed to guarantee the five features principle, including long blood circulation, efficient tumor accumulation, deep matrix penetration, enhanced cell internalization and accurate drug release. To ensure the excellent performance of the designed nanomedicine, it would be better to monitor the drug delivery process as well as the therapeutic effects by real-time imaging. In this review, we summarize strategies in developing nanomedicines for efficiently meeting the five features of drug delivery, and the role of several imaging modalities (fluorescent imaging (FL), magnetic resonance imaging (MRI), computed tomography (CT), photoacoustic imaging (PAI), positron emission tomography (PET), and electron microscopy) in tracing drug delivery and therapeutic effect in vivo based on five features principle.

Nanoparticle-Based Inhalation Therapy for Pulmonary Diseases

The lung is exposed to various pollutants and is the primary site for the onset of various diseases, including infections, allergies, and cancers. One possible treatment approach for such pulmonary diseases involves direct administration of therapeutics to the lung so as to maintain the topical concentration of the drug. Particles with nanoscale diameters tend to reach the pulmonary region. Nanoparticles (NPs) have garnered significant interest for applications in biomedical and pharmaceutical industries because of their unique physicochemical properties and biological activities. In this article, we describe the biological and pharmacological activities of NPs as well as summarize their potential in the formulation of drugs employed to treat pulmonary diseases. Recent advances in the use of NPs in inhalation chemotherapy for the treatment of lung diseases have also been highlighted.

Application of Dendrimers in Anticancer Diagnostics and Therapy

The application of dendrimeric constructs in medical diagnostics and therapeutics is increasing. Dendrimers have attracted attention due to their compact, spherical three-dimensional structures with surfaces that can be modified by the attachment of various drugs, hydrophilic or hydrophobic groups, or reporter molecules. In the literature, many modified dendrimer systems with various applications have been reported, including drug and gene delivery systems, biosensors, bioimaging contrast agents, tissue engineering, and therapeutic agents. Dendrimers are used for the delivery of macromolecules, miRNAs, siRNAs, and many other various biomedical applications, and they are ideal carriers for bioactive molecules. In addition, the conjugation of dendrimers with antibodies, proteins, and peptides allows for the design of vaccines with highly specific and predictable properties, and the role of dendrimers as carrier systems for vaccine antigens is increasing. In this work, we will focus on a review of the use of dendrimers in cancer diagnostics and therapy. Dendrimer-based nanosystems for drug delivery are commonly based on polyamidoamine dendrimers (PAMAM) that can be modified with drugs and contrast agents. Moreover, dendrimers can be successfully used as conjugates that deliver several substances simultaneously. The potential to develop dendrimers with multifunctional abilities has served as an impetus for the design of new molecular platforms for medical diagnostics and therapeutics.

HER-2-Targeted Nanoparticles for Breast Cancer Diagnosis and Treatment

Human epidermal growth factor receptor-2 (HER-2) overexpressing breast cancer is a breast cancer subtype characterized by high aggressiveness, high frequency of brain metastases and poor prognosis. HER-2, a glycoprotein belonging to the ErbB receptor family, is overexpressed on the outer membrane of cancer cells and has been an important therapeutic target for the development of targeted drugs, such as the monoclonal antibodies trastuzumab and pertuzumab. These therapies have been available in clinics for more than twenty years. However, despite the initial enthusiasm, a major issue emerged limiting HER-2 targeted therapy efficacy, i.e., the evolution of drug resistance, which could be tackled by nanotechnology. The aim of this review is to provide a first critical update on the different types of HER-2-targeted nanoparticles that have been proposed in the literature in the last decade for therapeutic purposes. We focus on the different targeting strategies that have been explored, their relative outcomes and current limitations that still need to be improved. Then, we review the nanotools developed as diagnostic kits, focusing on the most recent techniques, which allow accurate quantification of HER-2 levels in tissues, with the aim of promoting more personalized medicinal approaches in patients.

Dendrimer-based posaconazole nanoplatform for antifungal therapy

We examined formulating a new antifungal agent, posaconazole (POS) and its derivatives, with different molecular vehicles. Several combinations of drug and carrier molecules were synthesized, and their antifungal activities were evaluated against Aspergillus fumigatus. Posaconazole and four of its derivatives were conjugated to either generation 5 (G5) dendrimers or partially modified G5 dendrimers. The in vitro antifungal activities of these compounds suggest that conjugates with specific chemical linkages showed better fungistatic activity than direct conjugates to POS. In particular, a polyethylene glycol (PEG)-imidazole modified G5 dendrimer demonstrated improved antifungal efficacy relative to the parent G5 molecule. Further studies were then conducted with POS derived molecules coupled to PEG-imidazole modified G5 dendrimers to achieve a highly soluble and active conjugate of POS. This conjugated macromolecule averaged 23 POS molecules per G5 and had a high solubility with 50 mg/mL, which improved the molar solubility of POS from less than 0.03 mg/mL to as high as 16 mg/mL in water. The primary release profile of the drug in human plasma was extended to over 72 h, which is reflected in the in vitro inhibition of A. fumigatus growth of over 96 h. These POS–polymer conjugates appear to be novel and efficient antifungal agents.

Advances in antibody nanoconjugates for diagnosis and therapy: A review of recent studies and trends

Nowadays, the targeted imaging probe and drug delivery systems are the novel breakthrough area in the nanomedicine and treatment of various diseases. Conjugation of monoclonal antibodies and their fragments on nanoparticles (NPs) have a remarkable impact on personalized medicine, such that it provides specific internalization and accumulation in the tumor microenvironment. Targeted imaging and early detection of cancer is presumably the strong participant to a diminution in mortality and recurrence of cancer disease that will be the next generation of the imaging device in clinical application. These intelligent delivery systems can deliver therapeutic agents that target cancerous tissue with minimal side effects and a wide therapeutic window. Overall, the linkage between the antibody and NPs is a critical subject and requires precise design and development. The attachment of antibody nanoconjugates (Ab-NCs) on the antigen surface shouldn't affect the function of the antibody-antigen binding. Also, the stability of the antibody nanoconjugates in blood circulation is concerned to avoid the release of drug in non-targeted regions and the possible for specific toxicity while disposal to the desired site. Here, we update the recent progress of Ab-NCs to improve early detection and cancer therapy.