Stimuli-Responsive Nanocarrier for Co-delivery of MiR-31 and Doxorubicin To Suppress High MtEF4 Cancer

A detailed review on the role of miRNAs in mitochondrial-nuclear cross talk during cancer progression

MicroRNAs (miRNAs) are a class of small non-coding RNAs that are associated with biochemical pathways through the post-transcriptional regulation of gene expression in different cell types. Based on their expression pattern and function, miRNAs can have oncogenic and tumor suppressor activities in different cancer cells. Altered mitochondrial function and bioenergetics are known hallmarks of cancer cells. Mitochondria play a central role in metabolic reprogramming during cancer progression. Cancer cells exploit mitochondrial function for cell proliferation, invasion, migration and metastasis. Genetic and epigenetic changes in nuclear genome contribute to altered mitochondrial function and metabolic reprogramming in cancer cells. Recent studies have identified the role of miRNAs as major facilitators of anterograde and retrograde signaling between the nucleus and mitochondria in cancer cells. Detailed analysis of the miRNA-mediated regulation of mitochondrial function in cancer cells may provide new avenues for the diagnosis, prognosis, and therapeutic management of the disease. Our review aims to discuss the role of miRNAs in nuclear-mitochondrial crosstalk regulating mitochondrial functions in different cancer types. We further discussed the potential application of mitochondrial miRNAs (mitomiRs) targeting mitochondrial biogenesis and metabolism in developing novel cancer therapy.

Mapping the function of MicroRNAs as a critical regulator of tumor-immune cell communication in breast cancer and potential treatment strategies

Among women, breast cancer ranks as the most prevalent form of cancer, and the presence of metastases significantly reduces prognosis and diminishes overall survival rates. Gaining insights into the biological mechanisms governing the conversion of cancer cells, their subsequent spread to other areas of the body, and the immune system's monitoring of tumor growth will contribute to the advancement of more efficient and targeted therapies. MicroRNAs (miRNAs) play a critical role in the interaction between tumor cells and immune cells, facilitating tumor cells' evasion of the immune system and promoting cancer progression. Additionally, miRNAs also influence metastasis formation, including the establishment of metastatic sites and the transformation of tumor cells into migratory phenotypes. Specifically, dysregulated expression of these genes has been associated with abnormal expression of oncogenes and tumor suppressor genes, thereby facilitating tumor development. This study aims to provide a concise overview of the significance and function of miRNAs in breast cancer, focusing on their involvement as tumor suppressors in the antitumor immune response and as oncogenes in metastasis formation. Furthermore, miRNAs hold tremendous potential as targets for gene therapy due to their ability to modulate specific pathways that can either promote or suppress carcinogenesis. This perspective highlights the latest strategies developed for miRNA-based therapies.

Engineered mesoporous silica nanoparticles, new insight nanoplatforms into effective cancer gene therapy

The use of nucleic acid to control the expression of genes relevant to tumor progression is a key therapeutic approach in cancer research. Therapeutics based on nucleic acid provide novel concepts for untreatable targets. Nucleic acids as molecular medications must enter the target cell to be effective and obstacles in the systemic delivery of DNA or RNA limit their use in a clinical setting. The creation of nucleic acid delivery systems based on nanoparticles in order to circumvent biological constraints is advancing quickly. The ease of synthesis and surface modification, biocompatibility, biodegradability, cost-effectiveness and high loading capability of nucleic acids have prompted the use of mesoporous silica nanoparticles (MSNs) in gene therapy. The unique surface features of MSNs facilitate their design and decoration for high loading of nucleic acids, immune system evasion, cancer cell targeting, controlled cargo release, and endosomal escape. Reports have demonstrated successful therapeutic outcomes with the administration of a variety of engineered MSNs capable of delivering genes to tumor sites in laboratory animals. This comprehensive review of studies about siRNA, miRNA, shRNA, lncRNA and CRISPR/Cas9 delivery by MSNs reveals engineered MSNs as a safe and efficient system for gene transfer to cancer cells and cancer mouse models.

Natural Biopolymers as Smart Coating Materials of Mesoporous Silica Nanoparticles for Drug Delivery

In recent years, the functionalization of mesoporous silica nanoparticles (MSNs) with different types of responsive pore gatekeepers have shown great potential for the formulation of drug delivery systems (DDS) with minimal premature leakage and site-specific controlled release. New nanotechnological approaches have been developed with the objective of utilizing natural biopolymers as smart materials in drug delivery applications. Natural biopolymers are sensitive to various physicochemical and biological stimuli and are endowed with intrinsic biodegradability, biocompatibility, and low immunogenicity. Their use as biocompatible smart coatings has extensively been investigated in the last few years. This review summarizes the MSNs coating procedures with natural polysaccharides and protein-based biopolymers, focusing on their application as responsive materials to endogenous stimuli. Biopolymer-coated MSNs, which conjugate the nanocarrier features of mesoporous silica with the biocompatibility and controlled delivery provided by natural coatings, have shown promising therapeutic outcomes and the potential to emerge as valuable candidates for the selective treatment of various diseases.

Hyaluronic Acid-Based Nanomaterials Applied to Cancer: Where Are We Now?

Cancer cells normally develop the ability to rewire or reprogram themselves to become resistant to treatments that were previously effective. Despite progress in understanding drug resistance, knowledge gaps remain regarding the underlying biological causes of drug resistance and the design of cancer treatments to overcome it. So, resistance acquisition remains a major problem in cancer treatment. Targeted therapeutics are considered the next generation of cancer therapy because they overcome many limitations of traditional treatments. Numerous tumor cells overexpress several receptors that have a high binding affinity for hyaluronic acid (HA), while they are poorly expressed in normal body cells. HA and its derivatives have the advantage of being biocompatible and biodegradable and may be conjugated with a variety of drugs and drug carriers for developing various formulations as anticancer therapies such as micelles, nanogels, and inorganic nanoparticles. Due to their stability in blood circulation and predictable delivery patterns, enhanced tumor-selective drug accumulation, and decreased toxicity to normal tissues, tumor-targeting nanomaterial-based drug delivery systems have been shown to represent an efficacious approach for the treatment of cancer. In this review, we aim to provide an overview of some in vitro and in vivo studies related to the potential of HA as a ligand to develop targeted nanovehicles for future biomedical applications in cancer treatment.

Recent Trends in Nanomedicine-Based Strategies to Overcome Multidrug Resistance in Tumors

Cancer is the leading cause of economic and health burden worldwide. The commonly used approaches for the treatment of cancer are chemotherapy, radiotherapy, and surgery. Chemotherapy frequently results in undesirable side effects, and cancer cells may develop resistance. Combating drug resistance is a challenging task in cancer treatment. Drug resistance may be intrinsic or acquired and can be due to genetic factors, growth factors, the increased efflux of drugs, DNA repair, and the metabolism of xenobiotics. The strategies used to combat drug resistance include the nanomedicine-based targeted delivery of drugs and genes using different nanocarriers such as gold nanoparticles, peptide-modified nanoparticles, as well as biomimetic and responsive nanoparticles that help to deliver payload at targeted tumor sites and overcome resistance. Gene therapy in combination with chemotherapy aids in this respect. siRNA and miRNA alone or in combination with chemotherapy improve therapeutic response in tumor cells. Some natural substances, such as curcumin, quercetin, tocotrienol, parthenolide, naringin, and cyclosporin-A are also helpful in combating the drug resistance of cancer cells. This manuscript summarizes the mechanism of drug resistance and nanoparticle-based strategies used to combat it.

Core-shell alum-borneol fiber for high bioavailability

Currently, the treatment of burns poses a significant challenge to clinical surgical. The use of nanofibers combined with drugs provides an entirely new option for treating burns. Alum-borneol combination has been shown as a promising alternative in clinical burn treatment. However, the utilization of the alum-borneol combination is not optimistic due to the low solubility of borneol. In this study, alum-borneol incorporated polyvinyl pyrrolidone fibers with a core-shell structure were fabricated through coaxial electrospinning. In vitro Borneol release behavior of fibers with different ratios of alum to borneol was explored. Scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimeter, in vitro drug release, and in vitro release mechanism were evaluated. The results showed that the fiber membranes maintained an integrated morphology. In vitro dissolution data showed an improved solubility of borneol, which reached more than 82% at 240 min in alum-borneol fibers. It was 4.8 times higher than borneol powder, and the ratio of alum to borneol was 2:1 for the best results. Therefore, alum-borneol incorporated polyvinyl pyrrolidone fibers can significantly improve the dissolution rate of borneol, which opens up a new way for the combined application of the alum and borneol.

Role of microRNA alternation in the pathogenesis of gouty arthritis

Gouty arthritis is a common inflammatory disease. The condition is triggered by a disorder of uric acid metabolism, which causes urate deposition and gout flares. MicroRNAs are a class of conserved small non-coding RNAs that bind to the 3' untranslated region (UTR) of mRNA and regulate the expression of a variety of proteins at the post-transcriptional level. In recent years, attention has been focused on the role of miRNAs in various inflammatory diseases, including gouty arthritis. It is thought that miRNAs may regulate immune function and inflammatory responses, thereby influencing the onset and progression of the disease. This article mainly reviewed the roles of miRNAs in the pathogenesis of gouty arthritis and prospected their potential as diagnostic and prognostic relevant biomarkers and as possible therapeutic targets.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

Polysaccharide/mesoporous silica nanoparticle-based drug delivery systems: A review

Mesoporous silica nanoparticles (MSNs) have been well-researched in the design and fabrication of advanced drug delivery systems (DDSs) due to their advantages such as good biocompatibility, large specific surface area and pore volume for drug loading, easily surface modification, adjusted size and good thermal/chemical stability. For MSN-based DDSs, gate materials are also necessary. And natural polysaccharides, one kind of the most abundant natural resource, have been widely applied as the "gatekeepers" in MSN-based DDSs. Polysaccharides are cheap and rich in sources with good biocompatibility, and some of them have important biological functions. In this review article, polysaccharides including chitosan, hyaluronic acid, sodium alginate and dextran, et al. are briefly introduced. And the preparation processes and properties such as controlled drug release, cancer targeting and disease diagnosis of functional polysaccharide/MSN-based DDSs are discussed.

Nano-Coated si-SNHG14 Regulated PD-L1 Expression and Decreased Epithelial-Mesenchymal Transition in Nasopharyngeal Carcinoma Cells

To investigate the expression characteristics of long non-coding RNA SNHG14 in nasopharyngeal carcinoma (NPC) and its effects on epithelial-mesenchymal transition and development of nano-coated si-SNHG14 as an anti-tumor agent. The SNHG14 expression in cancerous and adjacent non-cancerous tissues was monitored using reverse transcriptionpolymerase chain reaction (RT-PCR). Gain- and loss-of-function experiments tested the regulation of SNHG14, miR- 5590-3p, and ZEB1 on PD-L1. The binding association between the above three factors was verified using bioinformatics analysis. EMT-related E-cadherin, N-cadherin, and Vimentin were tested using Western blot. Animal experiments in nude mice verified the function of SNHG14 in the EMT of NPC in vivo. The nano-coated si-SNHG14 was developed as an anti-tumor agent and was verified NPC cell in vitro. SNHG14 was upregulated in NPC tissues. Knocking down SNHG14 markedly inhibited the EMT of NPC. Additionally, the expression of ZEB1 was positively related to that of the SNHG14, while it was inversely correlated with that of miR-5590-3p. Moreover, ZEB1 transcription upregulated PD-L1 and promoted the EMT, while SNHG14 could accelerate the EMT of NPC in vivo by regulating the PD-1 and PD-L1. SNHG14-miR-5590- 3p-ZEB1 positively regulated PD-L1 and facilitate the EMT of NPC. Nano-coated si-SNHG14 significantly downregulated PD-L1 expression and decreased EMT.

Recent Developments in Delivery of MicroRNAs Utilizing Nanosystems for Metabolic Syndrome Therapy

Metabolic syndrome (MetS) is a set of complex, chronic inflammatory conditions that are characterized by central obesity and associated with an increased risk of cardiovascular diseases. In recent years, microRNAs (miRNAs) have become an important type of endocrine factors, which play crucial roles in maintaining energy balance and metabolic homeostasis. However, its unfavorable properties such as easy degradation in blood and off-target effect are still a barrier for clinical application. Nanosystem based delivery possess strong protection, high bioavailability and control release rate, which is beneficial for success of gene therapy. This review first describes the current progress and advances on miRNAs associated with MetS, then provides a summary of the therapeutic potential and targets of miRNAs in metabolic organs. Next, it discusses recent advances in the functionalized development of classic delivery systems (exosomes, liposomes and polymers), including their structures, properties, functions and applications. Furthermore, this work briefly discusses the intelligent strategies used in emerging novel delivery systems (selenium nanoparticles, DNA origami, microneedles and magnetosomes). Finally, challenges and future directions in this field are discussed provide a comprehensive overview of the future development of targeted miRNAs delivery for MetS treatment. With these contributions, it is expected to address and accelerate the development of effective NA delivery systems for the treatment of MetS.

Multifunctional hierarchical nanohybrids perform triple antitumor theranostics in a cascaded manner for effective tumor treatment

Gene therapy based on transfection of RNAs/DNAs offers tremendous promise for tumor treatment. However, the relatively weak therapeutic efficiency of current genetic nanohybrids in vivo has limited the application of this strategy. Herein, we fabricated multifunctional core-shell-corona nanohybrids by combining cascaded theranostics for enhanced gene therapy. The nanohybrids consist of polydopamine-modified Fe₃O₄ nanoparticles as core, anti-miRNA-21 oligonucleotides (anti-miRNA) strands as shell, and doxorubicin (DOX)-conjugated DNA-8pb (DOX-DNA-8bp) as corona. The polydopamine/Fe₃O₄ core not only serves as an active agent for local photothermal therapy under NIR irradiation, but it also provides magnetic targeting to tumor tissue for accurate treatment, which could enhance the therapeutic effect and reduce the undesired side effects to healthy tissues. The DOX-DNA-8bp corona was grafted on the anti-miRNA shell through base pairing, which could be replaced by overexpressed miRNA-21 in tumor cells due to the strong interaction between miRNA-21 and anti-miRNA, resulting in tumor-specific gene therapy through tumorigenic miRNA-21 consumption and tumor selective chemotherapy through miRNA-21-triggered DOX-DNA-8bp release in tumor cells. Moreover, the intelligent controlled release system can gradually stop the release of DOX to prevent side effects caused by drug overdose, once sufficient damage of tumor cells has occurred, due to the downregulation of miRNA-21. The results of both in vitro and in vivo analyses showed that the nanohybrids combining cascaded chemo-photo-gene therapy could effectively inhibit tumor growth, promote the survival of tumor-bearing mice, and show no visible adverse effects on these mice, resulting in a promising nanoplatform for tumor treatment. STATEMENT OF SIGNIFICANCE: Gene therapy based on transfection of RNAs/DNAs offers tremendous promise for cancer treatment. However, the relatively weak therapeutic efficiency of current genetic nanovectors in vivo that results in insufficient tumor targeting and easy decomposition/elimination of RNAs/DNAs during therapy has limited its application. Although some approaches have combined photothermal agents or antitumor drugs with RNA/DNA nanocarriers to achieve better treatment, the spatiotemporal differences in photothermal therapy, chemotherapy, and gene therapy using current nanohybrids may hinder their synergistic effect. In the present study, we fabricated multifunctional core-shell-corona nanohybrids (Fe₃O₄@PDA@anti-miRNA/DNA) to simultaneously perform on-demand photothermal therapy, miR-21-triggered chemotherapy, and miR-21-dependent gene therapy at the same location, which can achieve an efficient synergistic effect for precise and effective tumor treatment.

Nanobody: A Small Antibody with Big Implications for Tumor Therapeutic Strategy

The development of monoclonal antibody treatments for successful tumor-targeted therapies took several decades. However, the efficacy of antibody-based therapy is still confined and desperately needs further improvement. Nanobodies are the recombinant variable domains of heavy-chain-only antibodies, with many unique properties such as small size (~15kDa), excellent solubility, superior stability, ease of manufacture, quick clearance from blood, and deep tissue penetration, which gain increasing acceptance as therapeutical tools and are considered also as building blocks for chimeric antigen receptors as well as for targeted drug delivery. Thus, one of the promising novel developments that may address the deficiency of monoclonal antibody-based therapies is the utilization of nanobodies. This article provides readers the significant factors that the structural and biochemical properties of nanobodies and the research progress on nanobodies in the fields of tumor treatment, as well as their application prospect.

Therapeutic Targeting of MicroRNAs in the Tumor Microenvironment

The tumor-microenvironment (TME) is an amalgamation of various factors derived from malignant cells and infiltrating host cells, including cells of the immune system. One of the important factors of the TME is microRNAs (miRs) that regulate target gene expression at a post transcriptional level. MiRs have been found to be dysregulated in tumor as well as in stromal cells and they emerged as important regulators of tumorigenesis. In fact, miRs regulate almost all hallmarks of cancer, thus making them attractive tools and targets for novel anti-tumoral treatment strategies. Tumor to stroma cell cross-propagation of miRs to regulate protumoral functions has been a salient feature of the TME. MiRs can either act as tumor suppressors or oncogenes (oncomiRs) and both miR mimics as well as miR inhibitors (antimiRs) have been used in preclinical trials to alter cancer and stromal cell phenotypes. Owing to their cascading ability to regulate upstream target genes and their chemical nature, which allows specific pharmacological targeting, miRs are attractive targets for anti-tumor therapy. In this review, we cover a recent update on our understanding of dysregulated miRs in the TME and provide an overview of how these miRs are involved in current cancer-therapeutic approaches from bench to bedside.

Reactive oxygen species and glutathione dual responsive nanoparticles for enhanced prostate cancer therapy

Docetaxel (DTX)-based chemotherapy of prostate cancer is still confronted with significant challenges due to insufficient drug accumulation at the tumor sites and the systemic side effects on normal cells and organs. Tumor microenvironment-responsive nanosized drug delivery systems have shown enormous potential to improve the anticancer efficacy and minimize the systemic side effects of chemotherapeutics. However, most of the currently redox-responsive nanoparticles respond only to single stimuli, which compromise the treatment effect. Hence, inspired by the abundance of reactive oxygen species (ROS) and intracellular glutathione (GSH) in cancer cells, we proposed a unique ROS and GSH dual responsive nanocarrier (PCL-SS) for DTX delivery. The DTX-loaded PCL-SS nanoparticles (PCL-SS@DTX NPs) were not only stable in a normal physiological environment but also rapidly triggered DTX release in prostate cancer cells. In vitro experiments showed that PCL-SS@DTX NPs had robust prostate cancer cell cytotoxicity, induced cell apoptosis, inhibited cell migration and invasion and exhibited satisfactory biocompatibility. In mice bearing orthotopic prostate cancer, PCL-SS@DTX NPs could accumulate in orthotopic tumor sites and then significantly weaken tumor growth by inhibiting prostate cancer cell proliferation and inducing cell apoptosis, without obvious damages to major organs. Overall, this dual responsive nanosized drug delivery system may act as a promising therapeutic option for prostate cancer chemotherapy.

Mesoporous Silica Nanoparticles as Carriers for Biomolecules in Cancer Therapy

Mesoporous silica nanoparticles (MSNs) offer many advantageous properties for applications in the field of nanobiotechnology. Loading of small molecules into MSNs is straightforward and widely applied, but with the upswing of both research and commercial interest in biological drugs in recent years, also biomacromolecules have been loaded into MSNs for delivery purposes. MSNs possess many critical properties making them a promising and versatile carrier for biomacromolecular delivery. In this chapter, we review the effects of the various structural parameters of MSNs on the effective loading of biomacromolecular therapeutics, with focus on maintaining stability and drug delivery performance. We also emphasize recent studies involving the use of MSNs in the delivery of biomacromolecular drugs, especially for cancer treatment.

Hierarchical Gold Mesoflowers in Enzyme Engineering: An Environmentally Friendly Strategy for the Enhanced Enzymatic Performance and Biodiesel Production

To expand the field of nanomaterial and engineering of enzyme in eco-friendly processes, gold mesoflower (Au-MF) nanostructure was applied for preparation of three series of immobilized lipase (Au-MF/SAM 1-3) through biofunctionalization of surface by Ugi multicomponent reaction. The synthesized Au-MF/SAM 1-3/lipase as unique biocatalysts was confirmed by different analytical tools and techniques. Compared to the free lipase, the Au-MF/SAM 1-3/lipase showed more stability at high temperature and pH. Also, these biocatalysts showed high storage stability and reusability after 2 months and eight cycles, respectively. Moreover, the kinetic behavior was investigated and the results showed a minimal impairment of catalytic activity of immobilized lipase. The kinetic constants of the immobilized lipase, Au-MF/SAM 2/lipase, are K_m = 0.37 mM, V_max = 0.22 mM min^-1, and k_cat = 154 min^-1. The immobilized lipase showed smaller activation energy (E_a) than that of free enzyme, indicating that the immobilized enzyme is less sensitive to temperature. In the following, the biodiesel production from palmitic acid was studied in the presence of Au-MF/SAM 2/lipase as an efficient biocatalyst. The influence of different reaction parameters such as temperature, molar ratio of alcohol to palmitic acid, water content, and lipase amount was deeply investigated.

Preparation and Applications of Organo-Silica Hybrid Mesoporous Silica Nanoparticles for the Co-Delivery of Drugs and Nucleic Acids

Combination therapies rely on the administration of more than one drug, with independent mechanisms of action, aiming to enhance the efficiency of the treatment. For an optimal performance, the implementation of such therapies requires the delivery of the correct combination of drugs to a specific cellular target. In this context, the use of nanoparticles (NP) as platforms for the co-delivery of multiple drugs is considered a highly promising strategy. In particular, mesoporous silica nanoparticles (MSN) have emerged as versatile building blocks to devise complex drug delivery systems (DDS). This review describes the design, synthesis, and application of MSNs to the delivery of multiple drugs including nucleic acids for combination therapies.

Mesoporous silica nanoparticles: facile surface functionalization and versatile biomedical applications in oncology

Mesoporous silica nanoparticles (MSNs) have received increasing interest due to their tunable particle size, large surface area, stable framework, and easy surface modification. They are increasingly being used in varying applications as delivery vehicles including bio-imaging, drug delivery, biosensors and tissue engineering etc. Precise structure control and the ability to modify surface properties of MSNs are important for their applications. This review summarises the different synthetic methods for the preparation of well-ordered MSNs with tunable pore volume as well as the approaches of drugs loading, especially highlighting the facile surface functionalization for various purposes and versatile biomedical applications in oncology. Finally, the challenges of clinical transformation of MSNs-based nanomedicines are further discussed.

Rational design and latest advances of codelivery systems for cancer therapy

Current treatments have limited effectiveness in treating tumors. The combination of multiple drugs or treatment strategies is widely studied to improve therapeutic effect and reduce adverse effects of cancer therapy. The codelivery system is the key to realize combined therapies. It is necessary to design and construct different codelivery systems in accordance with the variable structures and properties of cargoes and vectors. This review presented the typical design considerations about codelivery vectors for cancer therapy and described the current state of codelivery systems from two aspects: different types of vectors and collaborative treatment strategies. The commonly used loading methods of cargoes into the vectors, including physical and chemical processes, are discussed in detail. Finally, we outline the challenges and perspectives about the improvement of codelivery systems.

Ligand-Installed Nanocarriers toward Precision Therapy

Development of drug-delivery systems that selectively target neoplastic cells has been a major goal of nanomedicine. One major strategy for achieving this milestone is to install ligands on the surface of nanocarriers to enhance delivery to target tissues, as well as to enhance internalization of nanocarriers by target cells, which improves accuracy, efficacy, and ultimately enhances patient outcomes. Herein, recent advances regarding the development of ligand-installed nanocarriers are introduced and the effect of their design on biological performance is discussed. Besides academic achievements, progress on ligand-installed nanocarriers in clinical trials is presented, along with the challenges faced by these formulations. Lastly, the future perspectives of ligand-installed nanocarriers are discussed, with particular emphasis on their potential for emerging precision therapies.

Nanogel: A Versatile Nano-Delivery System for Biomedical Applications

Nanogel-based nanoplatforms have become a tremendously promising system of drug delivery. Nanogels constructed by chemical crosslinking or physical self-assembly exhibit the ability to encapsulate hydrophilic or hydrophobic therapeutics, including but not limited to small-molecule compounds and proteins, DNA/RNA sequences, and even ultrasmall nanoparticles, within their 3D polymer network. The nanosized nature of the carriers endows them with a specific surface area and inner space, increasing the stability of loaded drugs and prolonging their circulation time. Reactions or the cleavage of chemical bonds in the structure of drug-loaded nanogels have been shown to trigger the controlled or sustained drug release. Through the design of specific chemical structures and different methods of production, nanogels can realize diverse responsiveness (temperature-sensitive, pH-sensitive and redox-sensitive), and enable the stimuli-responsive release of drugs in the microenvironments of various diseases. To improve therapeutic outcomes and increase the precision of therapy, nanogels can be modified by specific ligands to achieve active targeting and enhance the drug accumulation in disease sites. Moreover, the biomembrane-camouflaged nanogels exhibit additional intelligent targeted delivery features. Consequently, the targeted delivery of therapeutic agents, as well as the combinational therapy strategy, result in the improved efficacy of disease treatments, though the introduction of a multifunctional nanogel-based drug delivery system.

Overview of stimuli-responsive mesoporous organosilica nanocarriers for drug delivery

The application of nanomaterials is regarded nowadays as a highly promising approach for overcoming the limitations of the currently available cancer treatments, contributing for the creation of more effective, precise, and safer therapies. In the last years, organosilica nanoparticles arisen as alternatives to the most common mesoporous silica nanoparticles. The organosilica nanoparticles combine the advantages of the mesoporous silica, such as structural stability and mesoporous structure, with the increased biocompatibility and biodegradability of organic materials. Therefore, the variety of organic bridges that can be incorporated into the silica matrix allowed the development of new and exciting compositions, properties, and functions for improving the therapeutic effectiveness of the anticancer nanomedicines. In this review, the strategies that have been explored to create stimuli-responsive organosilica-based drug delivery systems are highlighted, describing the practical approaches and mechanisms controlling the drug release. Additionally, the organosilica nanoparticles surface modifications aimed for increasing the blood circulation time and the tumor targeting are also described.

Nanoscale delivery systems for microRNAs in cancer therapy

Concomitant with advances in research regarding the role of miRNAs in sustaining carcinogenesis, major concerns about their delivery options for anticancer therapies have been raised. The answer to this problem may come from the world of nanoparticles such as liposomes, exosomes, polymers, dendrimers, mesoporous silica nanoparticles, quantum dots and metal-based nanoparticles which have been proved as versatile and valuable vehicles for many biomolecules including miRNAs. In another train of thoughts, the general scheme of miRNA modulation consists in inhibition of oncomiRNA expression and restoration of tumor suppressor ones. The codelivery of two miRNAs or miRNAs in combination with chemotherapeutics or small molecules was also proposed. The present review presents the latest advancements in miRNA delivery based on nanoparticle-related strategies.

Advances in the discovery of microRNA-based anticancer therapeutics: latest tools and developments

Introduction: MicroRNAs (miRNAs) are small endogenous non-coding RNAs that repress the expression of their target genes by reducing mRNA stability and/or inhibiting translation. miRNAs are known to be aberrantly regulated in cancers. Modulators of miRNA (mimics and antagonists) have emerged as novel therapeutic tools for cancer treatment.Areas covered: This review summarizes the various strategies that have been applied to correct the dysregulated miRNA in cancer cells. The authors also discuss the recent advances in the technical development and preclinical/clinical evaluation of miRNA-based therapeutic agents.Expert opinion: Application of miRNA-based therapeutics for cancer treatment is appealing because they are able to modulate multiple dysregulated genes and/or signaling pathways in cancer cells. Major obstacles hindering their clinical development include drug delivery, off-target effects, efficacious dose determination, and safety. Tumor site-specific delivery of novel miRNA therapeutics may help to minimize off-target effects and toxicity. Combination of miRNA therapeutics with other anticancer treatment modalities could provide a synergistic effect, thus allowing the use of lower dose, minimizing off-target effects, and improving the overall safety profile in cancer patients. It is critical to identify individual miRNAs with cancer type-specific and context-specific regulation of oncogenes and tumor-suppressor genes in order to facilitate the precise use of miRNA anticancer therapeutics.

MicroRNAs and Metastasis

Metastasis, the development of secondary malignant growths at a distance from the primary site of a cancer, is associated with almost 90% of all cancer deaths, and half of all cancer patients present with some form of metastasis at the time of diagnosis. Consequently, there is a clear clinical need for a better understanding of metastasis. The role of miRNAs in the metastatic process is beginning to be explored. However, much is still to be understood. In this review, we present the accumulating evidence for the importance of miRNAs in metastasis as key regulators of this hallmark of cancer.

Nanomedicine in treatment of breast cancer - A challenge to conventional therapy

Amongst the various types of cancer, breast cancer is a highly heterogeneous disease and known as the leading cause of death among women globally. The extensive interdisciplinary investigation in nanotechnology and cancer biomedical research has been evolved over the years for its effective treatment. However, the advent of chemotherapeutic resistance in breast cancer is one of the major confront researchers are facing in achieving successful chemotherapy. Research in the area of cancer nanotechnology over the years have now been revolutionized through the development of smart polymers, lipids, inorganic materials and eventually their surface-engineering with targeting ligands. Moreover, nanotechnology further extended and brings in the notice the new theranostic approach which combining the therapy and imaging simultaneously. Currently, research is being envisaged in the area of novel nano-pharmaceutical design viz. liposome, nanotubes, polymer lipid hybrid system, which focuses to make the chemotherapy curative and long-lasting. In this review, we aimed to discuss the recent advancement of different surface-engineered/targeted nanomedicines that improved the drug efficacy in breast cancer.

Dual Stimuli-Responsive Controlled Release Nanocarrier for Multidrug Resistance Cancer Therapy

Multidrug resistance of cancer cells is a major obstacle for cancer chemotherapy. Herein, we present a nanocarrier that can release chemotherapeutic agents to induce tumor cell death and generate NO under NIR to overcome multidrug resistance in cancer chemotherapy. Owing to the unique structure of the water channel in this controlled release system for chemotherapeutic agents, the nanocarrier surface is equipped with more active sites to graft NO donor molecules. The released NO performs very well in reversing multidrug resistance by inhibiting P-gp expression. Our findings provide new insight into multidrug resistance cancer therapy and controlled release nanocarriers for multiple drugs.

Core-Shell Biopolymer Nanoparticles for Co-Delivery of Curcumin and Piperine: Sequential Electrostatic Deposition of Hyaluronic Acid and Chitosan Shells on the Zein Core

Curcumin and piperine are natural nutraceuticals that exhibit synergistic biological activities, but have different polarities, which can make their encapsulation within a single delivery system challenging. In this study, the two bioactive components were encapsulated within core-shell nanoparticles formed by a combination of antisolvent precipitation and layer-by-layer deposition. Initially, strongly hydrophobic curcumin (log P = 4.12) was embedded in the hydrophobic core of zein-hyaluronic acid nanoparticles using the antisolvent precipitation method. Then, the weakly hydrophobic piperine (log P = 2.78) was adsorbed to the outer biopolymer shell of these nanoparticles. Finally, the nutraceutical-loaded particles were coated with a layer of chitosan by the electrostatic deposition method. The surface charge and coating thickness depended on the number of adsorbed layers and the nature of the outer layer, being negative for hyaluronic acid and positive for chitosan. Low-, medium-, and high-molecular weight chitosan were utilized to modify the surface properties. Chitosan with a low-molecular weight was selected to fabricate the core-shell nanoparticles because it produced small highly charged cationic particles (d = 599 nm; ζ = +38.1 mV). The encapsulation efficiency and loading capacities were 90.4 and 5.7% for curcumin, and 86.4 and 5.4% for piperine, respectively. The core-shell nanoparticles protected the nutraceuticals from chemical degradation during light exposure, thermal processing, and storage for 2 months. Moreover, the nanoparticles were able to control the release of the bioactive components in simulated gastrointestinal conditions. Our results should facilitate the development of more effective nanodelivery systems for nutraceuticals that exhibit synergistic activities, but have different molecular characteristics.

Single-Molecule Characterization of Drug Delivery Systems

Delivery of the drug to a desired point of body and controlled release of the therapeutic agent are important features, provided by drug delivery systems (DDSs), for development of today's effective medicines. A variety of nanomaterials or nanomolecules such as lipids/liposomes, nucleic acids, peptides/proteins, composites, polymers, or carbon nanotubes can be used as DDSs. Single-molecule characterization of these small materials in terms of their size, shape, surface, encapsulation efficiency, as well as interaction with the drug-receiving cell has importance for their efficiency. The loading, distribution, or leakage of the drug as well as its interaction with DDS should also be characterized. Although diverse techniques are present for characterization of specific DDS material, methods such as electron microscopy and fluorescence microscopy are widely used. In this review, the current methodologies utilized for the single-molecule characterization of mostly preferred DDS materials were presented.

Coaxial Electrospinning Formation of Complex Polymer Fibers and their Applications

The formation of fibers by electrospinning has experienced explosive growth in the past decade, recently reaching 4,000 publications and 1,500 patents per year. This impressive growth of interest is due to the ability to form fibers with a variety of materials, which lend themselves to a large and rapidly expanding set of applications. In particular, coaxial electrospinning, which forms fibers with multiple core-sheath layers from different materials in a single step, enables the combination of properties in a single fiber that are not found in nature in a single material. This article is a detailed review of coaxial electrospinning: basic mechanisms, early history and current status, and an in-depth discussion of various applications (biomedical, environmental, sensors, energy, catalysis, textiles). We aim to provide readers who are currently involved in certain aspects of coaxial electrospinning research an appreciation of other applications and of current results.

Smart Collagen Hydrogels Based on 1-Ethyl-3-methylimidazolium Acetate and Microbial Transglutaminase for Potential Applications in Tissue Engineering and Cancer Therapy

For the first time, collagen-based hydrogels were fabricated in the presence of a biocompatible ionic liquid, 1-ethyl-3-methylimidazolium acetate ([EMIM] [Ac]), by a simple biopolymer cross-linking process facilitated by the strong catalytic hydrolysis of microbial transglutaminase (MTGase). Phosphate buffer solution (PBS)-encapsulated human-like collagen (HLC) or fish bone collagen (FBC) for the composite hydrogels was simply prepared by the codissolution of biopolymers in [EMIM] [Ac] or, in the absence of the ionic liquid, by the dispersion of MTGase in the biopolymer solution, leading to the formation of MTGase-aided hydrogels (Gel1 and Gel4) and [EMIM] [Ac]/MTGase-aided hydrogels (Gel2, Gel3, and Gel5). The effects of different contents of [EMIM] [Ac] and collagens of different origins (HLC and FBC) during fabrication on a range of structural and material characteristics, including the synthesis mechanism, three-dimensional structure, swelling behavior, mechanical strength, enzymatic hydrolysis rate, cytotoxicity, fibroblast cell proliferation rate, in vitro inhibition of cancer cells and cell adhesion, and in vivo histocompatibility, were investigated. Surprisingly, fabrication with [EMIM] [Ac] had significant effects on the structure and properties of the collagen/MTGase-based hydrogels. In other words, [EMIM] [Ac] changed the underlying mechanism responsible for the advantageous properties of the hydrogels by changing the three-dimensional structure of HLC or FBC, which improved their effects on fibroblast proliferation (3T3-L1 and L929 cells) and their in vitro inhibition of cancer cells (HepG2 and MKN45 cells). The use of the ionic liquid also imbued the hydrogels with degradation resistance and anti-inflammatory properties after subcutaneous injection into mice (in vivo). The catalytic hydrolysis by MTGase and the [EMIM] [Ac] content were the major factors that influenced the properties of the collagen. This result suggests the potential application of ionic liquid-enzymatic hydrolysis in the fabrication of collagen hydrogels in circumstances where the control of the properties by an ionic liquid is desirable. Therefore, [EMIM] [Ac] could be a promising solvent for the development of collagen into smart biomaterials with controlled biodegradation rates that can meet the needs of specific potential applications, such as tissue engineering and cancer therapy.

Fabrication and Characterization of Layer-by-Layer Composite Nanoparticles Based on Zein and Hyaluronic Acid for Codelivery of Curcumin and Quercetagetin

The utilization of layer-by-layer composite nanoparticles fabricated from zein and hyaluronic acid (HA) for the codelivery of curcumin and quercetagetin was investigated. A combination of hydrophobic effects and hydrogen bonding was responsible for the interaction of zein with both curcumin and quercetagetin inside the nanoparticles. Electrostatic attraction and hydrogen bonding were mainly responsible for the layer-by-layer deposition of hyaluronic acid on the surfaces of the nanoparticles. The secondary structure of zein was altered by the presence of the two nutraceuticals and HA. The optimized nanoparticle formulation contained relatively small particles ( d = 231.2 nm) that were anionic (ζ = -30.5 mV). The entrapment efficiency and loading capacity were 69.8 and 2.5% for curcumin and 90.3 and 3.5% for quercetagetin, respectively. Interestingly, the morphology of the nanoparticles depended on their composition. In particular, they changed from coated nanoparticles to nanoparticle-filled microgels as the level of HA increased. The nanoparticles were effective at reducing light and thermal degradation of the two encapsulated nutraceuticals and remained physically stable throughout 6 months of long-term storage. In addition, the nanoparticles were shown to slowly release the nutraceuticals under simulated gastrointestinal tract conditions, which may help improve their oral bioavailability. In summary, we have shown that layer-by-layer composite nanoparticles based on zein and HA are an effective codelivery system for two bioactive compounds.

New insights towards mesoporous silica nanoparticles as a technological platform for chemotherapeutic drugs delivery

Mesoporous silica nanoparticles (MSNs) displays interesting properties for biomedical applications such as high chemical stability, large surface area and tunable pores diameters and volumes, allowing the incorporation of large amounts of drugs, protecting them from deactivation and degradation processes acting as an excellent nanoplatform for drug delivery. However, the functional MSNs do not present the ability to transport the therapeutics without any leakage until reach the targeted cells causing side effects. On the other hand, the hydroxyls groups available on MSNs surface allows the conjugation of specific molecules which can binds to the overexpressed Enhanced Growth Factor Receptor (EGFR) in many tumors, representing a potential strategy for the cancer treatment. Beyond that, the targeting molecules conjugate onto mesoporous surface increase its cell internalization and act as gatekeepers blocking the mesopores controlling the drug release. In this context, multifunctional MSNs emerge as stimuli-responsive controlled drug delivery systems (CDDS) to overcome drawbacks as low internalization, premature release before to reach the region of interest, several side effects and low effectiveness of the current treatments. This review presents an overview of MSNs fabrication methods and its properties that affects drug delivery as well as stimuli-responsive CDDS for cancer treatment.

Advances in Therapeutic Implications of Inorganic Drug Delivery Nano-Platforms for Cancer

Numerous nanoparticles drug delivery systems for therapeutic implications in cancer treatment are in preclinical development as conventional chemotherapy has several drawbacks. A chemotherapeutic approach requires high doses of chemotherapeutic agents with low bioavailability, non-specific targeting, and above all, development of multiple drug resistance. In recent years, inorganic nano-drug delivery platforms (NDDPs; with a metal core) have emerged as potential chemotherapeutic systems in oncology. One of the major goals of developing inorganic NDDPs is to effectively address the targeted anti-cancer drug(s) delivery related problems by carrying the therapeutic agents to desired tumors sites. In this current review, we delve into summarizing the recent developments in targeted release of anti-cancer drugs loaded in inorganic NDDPs such as mesoporous silica nanoparticles, carbon nanotubes, layered double hydroxides, superparamagnetic iron oxide nanoparticles and calcium phosphate nanoparticles together with highlighting their therapeutic performance at tumor sites.

Non-viral nanocarriers for intracellular delivery of microRNA therapeutics

MicroRNAs are small regulatory noncoding RNAs that regulate various biological processes. Herein, we will present the development of the strategies for intracellular miRNAs delivery, and specially focus on the rational designed routes, their mechanisms of action, as well as potential therapeutics used in the host cells orin vivostudies.