Targeted delivery systems for oligonucleotide therapeutics

The impact of lipidome on breast cancer: a Mendelian randomization study

OBJECTIVE

This study aims to investigate the association between specific lipidomes and the risk of breast cancer (BC) using the Two-Sample Mendelian Randomization (TSMR) approach and Bayesian Model Averaging Mendelian Randomization (BMA-MR) method.

METHOD

The study analyzed data from large-scale GWAS datasets of 179 lipidomes to assess the relationship between lipidomes and BC risk across different molecular subtypes. TSMR was employed to explore causal relationships, while the BMA-MR method was carried out to validate the results. The study assessed heterogeneity and horizontal pleiotropy through Cochran's Q, MR-Egger intercept tests, and MR-PRESSO. Moreover, a leave-one-out sensitivity analysis was performed to evaluate the impact of individual single nucleotide polymorphisms on the MR study.

RESULTS

By examining 179 lipidome traits as exposures and BC as the outcome, the study revealed significant causal effects of glycerophospholipids, sphingolipids, and glycerolipids on BC risk. Specifically, for estrogen receptor-positive BC (ER+ BC), phosphatidylcholine (P < 0.05) and phosphatidylinositol (OR: 0.916-0.966, P < 0.05) within glycerophospholipids play significant roles, along with the importance of glycerolipids (diacylglycerol (OR = 0.923, P < 0.001) and triacylglycerol, OR: 0.894-0.960, P < 0.05)). However, the study did not observe a noteworthy impact of sphingolipids on ER+BC. In the case of estrogen receptor-negative BC (ER- BC), not only glycerophospholipids, sphingolipids (OR = 1.085, P = 0.008), and glycerolipids (OR = 0.909, P = 0.002) exerted an influence, but the protective effect of sterols (OR: 1.034-1.056, P < 0.05) was also discovered. The prominence of glycerolipids was minimal in ER-BC. Phosphatidylethanolamine (OR: 1.091-1.119, P < 0.05) was an important causal effect in ER-BC.

CONCLUSIONS

The findings reveal that phosphatidylinositol and triglycerides levels decreased the risk of BC, indicating a potential protective role of these lipid molecules. Moreover, the study elucidates BC's intricate lipid metabolic pathways, highlighting diverse lipidome structural variations that may have varying effects in different molecular subtypes.

Splice-Modulating Antisense Oligonucleotides as Therapeutics for Inherited Metabolic Diseases

The last decade (2013-2023) has seen unprecedented successes in the clinical translation of therapeutic antisense oligonucleotides (ASOs). Eight such molecules have been granted marketing approval by the United States Food and Drug Administration (US FDA) during the decade, after the first ASO drug, fomivirsen, was approved much earlier, in 1998. Splice-modulating ASOs have also been developed for the therapy of inborn errors of metabolism (IEMs), due to their ability to redirect aberrant splicing caused by mutations, thus recovering the expression of normal transcripts, and correcting the deficiency of functional proteins. The feasibility of treating IEM patients with splice-switching ASOs has been supported by FDA permission (2018) of the first "N-of-1" study of milasen, an investigational ASO drug for Batten disease. Although for IEM, owing to the rarity of individual disease and/or pathogenic mutation, only a low number of patients may be treated by ASOs that specifically suppress the aberrant splicing pattern of mutant precursor mRNA (pre-mRNA), splice-switching ASOs represent superior individualized molecular therapeutics for IEM. In this work, we first summarize the ASO technology with respect to its mechanisms of action, chemical modifications of nucleotides, and rational design of modified oligonucleotides; following that, we precisely provide a review of the current understanding of developing splice-modulating ASO-based therapeutics for IEM. In the concluding section, we suggest potential ways to improve and/or optimize the development of ASOs targeting IEM.

miR-142: A Master Regulator in Hematological Malignancies and Therapeutic Opportunities

MicroRNAs (miRNAs) are a type of non-coding RNA whose dysregulation is frequently associated with the onset and progression of human cancers. miR-142, an ultra-conserved miRNA with both active -3p and -5p mature strands and wide-ranging physiological targets, has been the subject of countless studies over the years. Due to its preferential expression in hematopoietic cells, miR-142 has been found to be associated with numerous types of lymphomas and leukemias. This review elucidates the multifaceted role of miR-142 in human physiology, its influence on hematopoiesis and hematopoietic cells, and its intriguing involvement in exosome-mediated miR-142 transport. Moreover, we offer a comprehensive exploration of the genetic and molecular landscape of the miR-142 genomic locus, highlighting its mutations and dysregulation within hematological malignancies. Finally, we discuss potential avenues for harnessing the therapeutic potential of miR-142 in the context of hematological malignancies.

The mirrored cationic peptide as miRNA vehicle for efficient lung cancer therapy

Gene therapy has emerged as a potential approach for lung cancer therapy. However, the application of gene therapy is still limited by their properties, such as low specificity to the cancer cells, negatively charged groups, short systemic circulation time, and rapid degradation by nucleases. The progression of lung adenocarcinoma (LUAD) can be promoted through the methylation process of miR-148a-3p promoter, as confirmed by our previous research. In the current study, we are the first to design a mirrored Arg-Gly-Asp (RGD)-modified cationic peptide (RD24) as a microRNA (miRNA) vehicle, which enabled to pack the miRNA (miR-148a-3p) efficiently and generate RD24/miR-148a-3p nanoparticles (RPRIN) by self-assembling. RPRIN exhibited a high transfection efficiency in lung cancer cells via the conjugation between RGD and integrins on the surface of lung cancer cells. Furthermore, RD24 showed matrix metallopeptidase 2 (MMP2) responsiveness, which improved lung cancer cell inhibition induced by the miRNA intracellularly. In addition, RPRIN exhibits several advantages, such as prolonged circulation duration, reduced toxicity, and immune escape. Experiments conducted both in vitro and in vivo revealed that RPRIN effectively suppressed the growth and progression of lung cancer. Thus, the mirrored RGD-modified cationic peptide showed great potential in transducing miRNA for lung cancer therapy.

Breast cancer: miRNAs monitoring chemoresistance and systemic therapy

With a high mortality rate that accounts for millions of cancer-related deaths each year, breast cancer is the second most common malignancy in women. Chemotherapy has significant potential in the prevention and spreading of breast cancer; however, drug resistance often hinders therapy in breast cancer patients. The identification and the use of novel molecular biomarkers, which can predict response to chemotherapy, might lead to tailoring breast cancer treatment. In this context, accumulating research has reported microRNAs (miRNAs) as potential biomarkers for early cancer detection, and are conducive to designing a more specific treatment plan by helping analyze drug resistance and sensitivity in breast cancer treatment. In this review, miRNAs are discussed in two alternative ways-as tumor suppressors to be used in miRNA replacement therapy to reduce oncogenesis and as oncomirs to lessen the translation of the target miRNA. Different miRNAs like miR-638, miR-17, miR-20b, miR-342, miR-484, miR-21, miR-24, miR-27, miR-23 and miR-200 are involved in the regulation of chemoresistance through diverse genetic targets. For instance, tumor-suppressing miRNAs like miR-342, miR-16, miR-214, and miR-128 and tumor-promoting miRNAs like miR101 and miR-106-25 cluster regulate the cell cycle, apoptosis, epithelial to mesenchymal transition and other pathways to impart breast cancer drug resistance. Hence, in this review, we have discussed the significance of miRNA biomarkers that could assist in providing novel therapeutic targets to overcome potential chemotherapy resistance to systemic therapy and further facilitate the design of tailored therapy for enhanced efficacy against breast cancer.

Therapeutic Delivery of Tumor Suppressor miRNAs for Breast Cancer Treatment

The death rate from breast cancer (BC) has dropped due to early detection and sophisticated therapeutic options, yet drug resistance and relapse remain barriers to effective, systematic treatment. Multiple mechanisms underlying miRNAs appear crucial in practically every aspect of cancer progression, including carcinogenesis, metastasis, and drug resistance, as evidenced by the elucidation of drug resistance. Non-coding RNAs called microRNAs (miRNAs) attach to complementary messenger RNAs and degrade them to inhibit the expression and translation to proteins. Evidence suggests that miRNAs play a vital role in developing numerous diseases, including cancer. They affect genes critical for cellular differentiation, proliferation, apoptosis, and metabolism. Recently studies have demonstrated that miRNAs serve as valuable biomarkers for BC. The contrast in the expression of miRNAs in normal tissue cells and tumors suggest that miRNAs are involved in breast cancer. The important aspect behind cancer etiology is the deregulation of miRNAs that can specifically influence cellular physiology. The main objective of this review is to emphasize the role and therapeutic capacity of tumor suppressor miRNAs in BC and the advancement in the delivery system that can deliver miRNAs specifically to cancerous cells. Various approaches are used to deliver these miRNAs to the cancer cells with the help of carrier molecules, like nanoparticles, poly D, L-lactic-co-glycolic acid (PLGA) particles, PEI polymers, modified extracellular vesicles, dendrimers, and liposomes. Additionally, we discuss advanced strategies of TS miRNA delivery techniques such as viral delivery, self-assembled RNA-triple-helix hydrogel drug delivery systems, and hyaluronic acid/protamine sulfate inter-polyelectrolyte complexes. Subsequently, we discuss challenges and prospects on TS miRNA therapeutic delivery in BC management so that miRNAs will become a routine technique in developing individualized patient profiles.

Nanoparticle-Delivered Transforming Growth Factor-β1 siRNA Induces PD-1 against Gastric Cancer by Transforming the Phenotype of the Tumor Immune Microenvironment

Immune checkpoint blockade (ICB) is currently considered to be an important therapeutic method, which obtained FDA approval for clinical use in gastric cancer in 2017. As a new mechanism, it was found that the effect of αPDL1 could be improved by blocking the TGF-β1 signaling pathway, which converts the tumor immune microenvironment from the "immune-excluded phenotype" to the "immune-inflamed phenotype". Based on this phenomenon, this project was designed to prepare TGF-β1-siRNA-loaded PEG-PCL nanoparticles conjugated to αPDL1 (siTGF-β1-αPDL1-PEG-PCL) since we have linked similar antibodies to PEG-PCL previously. Therefore, MFC tumor-engrafted mice were established to simulate the biological characteristics of converting the phenotype of the immune microenvironment, and to study the anti-tumor effect and possible molecular mechanism. In this study, αPDL1 antibody conjugates markedly increased the cell uptake of NPs. The produced αPDL1-PEG-PCL NPs efficiently reduced the amounts of TGF-β1 mRNA in MFC cells, converting the immune microenvironment of MFC tumors engrafted mice from the "immune-excluded phenotype" to the "immune-inflamed phenotype". PDL1-harboring gastric cancer had increased susceptibility to αPDL1. The value of this drug-controlled release system targeting the tumor microenvironment in immune checkpoint therapy of gastric cancer would provide a scientific basis for clinically applying nucleic acid drugs.

Conformationally Restricted Dipeptide-Based Nanoparticles for Delivery of siRNA in Experimental Liver Cirrhosis

Liver cirrhosis is a major health problem with multiple associated complications. The presently available drug delivery systems showed moderate site-specific delivery of antifibrotic molecules to the diseased liver; therefore, research on more effective and selective delivery systems in the context of liver cirrhosis remains a necessity in clinical investigation. The aim of the present study was to develop a peptide-based targeted nanocarrier to deliver an oligonucleotide to the hepatic sinusoidal and perivascular regions of the cirrhotic liver. We have synthesized and characterized a conformationally restricted targeted pentapeptide (RΔFRGD), which contains an unnatural amino acid, α,β-dehydrophenylalanine (ΔF). The RΔFRGD self-assembled into spherical nanoparticles (NPs) and was characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Next, we investigated the delivery potential of the pentapeptide-based NPs to make a stable complex with a well-established small interference RNA and studied its site-specific delivery in experimental liver cirrhosis. We used siNR4A1 of the orphan nuclear receptor 4A1 (NR4A1), a well-known regulatory checkpoint for controlling liver fibrosis. Peptide NPs and their complex with siNR4A1 showed high biocompatibility against various mammalian cell lines. Hepatic tissue biodistribution analysis illustrated that targeted NPs predominantly accumulated in the cirrhotic liver compared to normal rats, specifically in sinusoidal and perivascular areas. A significant downregulation of the NR4A1 mRNA expression (-70%) andlower levels of the NR4A1/GAPDH ratio (-55%) were observed in the RΔFRGD-siNR4A1 nanocomplex-treated group in comparison to the RΔFRGD-vehicle group (RΔFRGD-Veh) at the gene and protein levels, respectively. In addition, in vivo inhibition of NR4A1 produced a significant aggravation in hepatic fibrosis compared with siRNA-vehicle-treated rats (+41% in the MT stain). The novel pentapeptide-based targeted delivery system can be further evaluated and validated for therapeutic purposes in various pathological conditions.

Aptamer-Functionalized Nanoparticles Mediate PD-L1 siRNA Delivery for Effective Gene Silencing in Triple-Negative Breast Cancer Cells

Small interfering RNA (siRNA) therapies require effective delivery vehicles capable of carrying the siRNA cargo into target cells. To achieve tumor-targeting, a drug delivery system would have to incorporate ligands that specifically bind to receptors expressed on cancer cells to function as portals via receptor-mediated endocytosis. Cell-targeting and internalizing aptamers are the most suitable ligands for functionalization of drug-loaded nanocarriers. Here, we designed a novel aptamer-based platform for the active delivery of siRNA targeting programmed cell death-ligand 1 (PD-L1) to triple-negative breast cancer (TNBC) cells. The generated nanovectors consist of PLGA-based polymeric nanoparticles, which were loaded with PD-L1 siRNA and conjugated on their surface with a new RNA aptamer, specific for TNBC and resistant to nucleases. In vitro results demonstrated that these aptamer-conjugated nanoparticles promote siRNA uptake specifically into TNBC MDA-MB-231 and BT-549 target cells, along with its endosomal release, without recognizing non-TNBC BT-474 breast cancer cells. Their efficiency resulted in an almost complete suppression of PD-L1 expression as early as 90 min of cell treatment. This research provides a rational strategy for optimizing siRNA delivery systems for TNBC treatments.

Enhanced anti-breast cancer efficacy of co-delivery liposomes of docetaxel and curcumin

The successful treatment of breast cancer is hampered by toxicity to normal cells, impaired drug accumulation at the tumor site, and multidrug resistance. We designed a novel multifunctional liposome, CUR-DTX-L, to co-deliver curcumin (CUR) and the chemotherapeutic drug docetaxel (DTX) for the treatment of breast cancer in order to address multidrug resistance (MDR) and the low efficacy of chemotherapy. The mean particle size, polydispersity index, zeta potential, and encapsulation efficiency of CUR-DTX-L were 208.53 ± 6.82 nm, 0.055 ± 0.001, -23.1 ± 2.1 mV, and 98.32 ± 2.37%, respectively. An in vitro release study and CCK-8 assays showed that CUR-DTX-L has better sustained release effects and antitumor efficacy than free drugs, the antitumor efficacy was verified by MCF-7 tumor-bearing mice, the CUR-DTX-L showed better antitumor efficacy than other groups, and the in vivo pharmacokinetic study indicated that the plasma concentration-time curve, mean residence time, and biological half-life time of CUR-DTX-L were significantly increased compared with free drugs, suggesting that it is a promising drug delivery system for the synergistic treatment of breast cancer.

Tumor necrosis factor alpha delivers exogenous inflammation-related microRNAs to recipient cells with functional targeting capabilities

Tumor necrosis factor alpha (TNF-α) is a critical pro-inflammatory cytokine in a wide range of tumors and infectious diseases. This study showed for the first time that TNF-α could specifically bind to certain intracellular or circulating inflammation-related microRNAs both in vitro and in vivo. The binding sites of TNF-α to microRNAs are located at the N-terminal of TNF-α and the 3'-GGUU motif of microRNAs. TNF-α could deliver exogenous unmodified single-stranded microRNAs into recipient cells through the TNF-α receptors (TNFRs) and stabilize them from being degraded by RNase in cells. Exogenous miR-146a or let-7c delivered into HCT116 cells by TNF-α could escape from lysosomes and specifically downregulate their target genes and then affect cell proliferation and migration in vitro, as well as tumorigenesis in vivo. Based on the above findings, the concept of "non-conjugated ligand-mediated RNA delivery (ncLMRD)" was proposed, which may serve as a promising strategy for therapeutic microRNA delivery in the future.

Nanomedicine for the Delivery of RNA in Cancer

Simple Summary

Cancer is a multifaceted, life-threatening, and genomically complex disease. The worldwide prevalence of cancer is so high that one in three people will develop cancer during their lifetime. Although the use of RNA therapy is promising to fight cancer, its efficient and safe delivery is still one of the significant challenges hampering its therapeutic application. Thus, the aim of the present review was to highlight the most recent developments in the field of nanomedicine RNA-associated therapies to fight cancer.

Abstract

The complexity, and the diversity of the different types of cancers allied to the tendency to form metastasis make treatment efficiency so tricky and often impossible due to the advanced stage of the disease in the diagnosis. In recent years, due to tremendous scientific breakthroughs, we have witnessed exponential growth in the elucidation of mechanisms that underlie carcinogenesis and metastasis. The development of more selective therapies made it possible to improve cancer treatment. Although interdisciplinary research leads to encouraging results, scientists still have a long exploration journey. RNA technology represents a promise as a therapeutic intervention for targeted gene silencing in cancer, and there are already some RNA-based formulations in clinical trials. However, the use of RNA as a therapeutic tool presents severe limitations, mainly related to its low stability and poor cellular uptake. Thus, the use of nanomedicine employing nanoparticles to encapsulate RNA may represent a suitable platform to address the major challenges hampering its therapeutic application. In this review, we have revisited the potential of RNA and RNA-associated therapies to fight cancer, also providing, as support, a general overview of nanoplatforms for RNA delivery.

Novel molecular approaches to combat vectors and vector-borne viruses: Special focus on RNA interference (RNAi) mechanisms

Vector-borne diseases, such as dengue, chikungunya, zika, yellow fever etc pose significant burden among the infectious diseases globally, especially in tropical and sub-tropical regions. Globalization, deforestation, urbanization, climate change, uncontrolled population growth, inadequate waste management and poor vector-management infrastructure have all contributed to the expansion of vector habitats and subsequent increase in vector-borne diseases throughout the world. Conventional vector control methods, such as use of insecticides, have significant negative environmental repercussions in addition to developing resistance in vectors. Till date, a very few vaccines or antiviral therapies have been approved for the treatment of vector borne diseases. In this review, we have discussed emerging molecular approaches like CRISPR (clustered regularly interspaced short palindromic repeats)/Cas-9, sterile insect technique (SIT), release of insects carrying a dominant lethal (RIDL), Wolbachia (virus transmission blocking) and RNA interference (RNAi) to combat vector and vector-borne viruses. Due to the extensive advancements in RNAi research, a special focus has been given on its types, biogenesis, mechanism of action, delivery and experimental studies evaluating their application as anti-mosquito and anti-viral agent. These technologies appear to be highly promising in terms of contributing to vector control and antiviral drug development, and hence can be used to reduce global vector and vector-borne disease burden.

Biomarkers in Pancreatic Cancer as Analytic Targets for Nanomediated Imaging and Therapy

As the increase in therapeutic and imaging technologies is swiftly improving survival chances for cancer patients, pancreatic cancer (PC) still has a grim prognosis and a rising incidence. Practically everything distinguishing for this type of malignancy makes it challenging to treat: no approved method for early detection, extended asymptomatic state, limited treatment options, poor chemotherapy response and dense tumor stroma that impedes drug delivery. We provide a narrative review of our main findings in the field of nanoparticle directed treatment for PC, with a focus on biomarker targeted delivery. By reducing drug toxicity, increasing their tumor accumulation, ability to modulate tumor microenvironment and even improve imaging contrast, it seems that nanotechnology may one day give hope for better outcome in pancreatic cancer. Further conjugating nanoparticles with biomarkers that are overexpressed amplifies the benefits mentioned, with potential increase in survival and treatment response.

Overcoming the Tumor Microenvironmental Barriers of Pancreatic Ductal Adenocarcinomas for Achieving Better Treatment Outcomes

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease with the lowest survival rate among all solid tumors. The lethality of PDAC arises from late detection and propensity of the tumor to metastasize and develop resistance against chemo and radiation therapy. A highly complex tumor microenvironment composed of dense stroma, immune cells, fibroblast, and disorganized blood vessels, is the main obstacle to current PDAC therapy. Despite the tremendous success of immune checkpoint inhibitors (ICIs) in cancers, PDAC remains one of the poorest responders of ICIs therapy. The immunologically "cold" phenotype of PDAC is attributed to the low mutational burden, high infiltration of myeloid-derived suppressor cells and T-regs, contributing to a significant immunotherapy resistance mechanism. Thus, the development of innovative strategies for turning immunologically "cold" tumor into "hot" ones is an unmet need to improve the outcome of PDAC ICIs therapies. Other smart strategies, such as nanomedicines, sonic Hedgehog inhibitor, or smoothened inhibitor, are discussed to enhance chemotherapeutic agents' efficiency by disrupting the PDAC stroma. This review highlights the current challenges and various preclinical and clinical strategies to overcome current PDAC therapy difficulties, thus significantly advancing PDAC research knowledge.

Extension in the approaches to treat cancer through siRNA system: a beacon of hope in cancer therapy

Along with the evolutionary breakthrough of RNA interference and the applicability for gene knockdown, a subsequent development in siRNA-based therapeutics has been attained. The gene therapy based on RNAi is in transition progress from the research aspects to clinical base. Being a potent tool, siRNA is used as therapeutic against several disorders. Cancer which is one of the deadliest diseases is now treated with an advanced mechanism of siRNA delivery inside the genome, leading to gene silencing; thereby, blocking translation of gene to form protein. siRNA tool delivers remedial effects with the advantages of safe delivery and efficiency. Despite its merits, barriers including instability at physiological conditions, lack of ability to cross biological membranes, off-targets, and safety are also associated with siRNA delivery system. The gene silencing efficiency values both in vitro and in vivo reported in the past years have been reviewed by material type (lipid, polymer, silica, porous silicon, and metal). This review presents a deep insight in the development of targeted delivery of siRNA. Since several clinical trials have also been performed regarding the siRNA delivery against cancer, it can also be stated that the delivery system should be good enough to achieve effective siRNA drug development.

Improved delivery of miR-1296 loaded cationic nanoliposomes for effective suppression of triple negative breast cancer

Nowadays, microRNA is considered an attractive strategy for the effective treatment of cancer. A significant delivery of microRNA for cancer therapy remains a significant obstacle to target cancer cells. The restoring microRNA-1296 (miR-1296) has immense therapeutic efficacy in triple-negative breast cancer (TNBC). TNBC is an aggressive subtype of breast tumors with the progression of malignant transformation. This study aimed to develop a cationic nanoliposome that can serve as a miR-1296 carrier and studied its efficiency in TNBC. The efficacy of miR-1296 liposomes was evaluated on its apoptotic effect, cellular uptake, and potential chemotherapy sensitization in the TNBC cell line (MDA-MB-231). For in vitro viability study, the apoptotic effect was performed to validate protein expression using Alamar blue kit and western blot. The transfection of miR-1296 into TNBC cells was also investigated using cisplatin as a TNBC resistance drug. The fluorescent miR-1296-cy3 liposome was used for cellular uptake study. The miR-liposome was successfully prepared with a particle size of 123.6 ± 1.3 nm and encapsulation efficiency of 94.33%. A dose of 0.5 uM has significantly reduced the viability of MDA-MB-231 to be 33.45%±5.29 (P < 0.001). This result was validated by down-expression of CCND1, and PARP1, the miR-1296 receptor, and apoptosis marker. The image of the miR-1296-cy3 liposome showed cytoplasmic intracellular localization. It was found high sensitization of TNBC cell line for miR-1296 liposome compared to cisplatin (P < 0.001). Future in vivo research may answer questions concerning safety and stability. This study demonstrates that miR-191 liposomes may have promising clinical applications for TNBC therapy.

MiRNAs and Muscle Regeneration: Therapeutic Targets in Duchenne Muscular Dystrophy

microRNAs (miRNAs) are small non-coding RNAs required for the post-transcriptional control of gene expression. MicroRNAs play a critical role in modulating muscle regeneration and stem cell behavior. Muscle regeneration is affected in muscular dystrophies, and a critical point for the development of effective strategies for treating muscle disorders is optimizing approaches to target muscle stem cells in order to increase the ability to regenerate lost tissue. Within this framework, miRNAs are emerging as implicated in muscle stem cell response in neuromuscular disorders and new methodologies to regulate the expression of key microRNAs are coming up. In this review, we summarize recent advances highlighting the potential of miRNAs to be used in conjunction with gene replacement therapies, in order to improve muscle regeneration in the context of Duchenne Muscular Dystrophy (DMD).

siRNA delivery to macrophages using aspherical, nanostructured microparticles as delivery system for pulmonary administration

The delivery of oligonucleotides such as siRNA to the lung is a major challenge, as this group of drugs has difficulties to overcome biological barriers due to its polyanionic character and the associated hydrophilic properties, resulting in inefficient delivery. Especially in diseases such as asthma, chronic obstructive pulmonary disease and cystic fibrosis, where increased proinflammation is present, a targeted RNA therapy is desirable due to the high potency of these oligonucleotides. To address these problems and to ensure efficient uptake of siRNA in macrophages, a microparticulate, cylindrical delivery system was developed. In the first step, this particle system was tested for its aerodynamic characteristics to evaluate the aerodynamic properties to optimize lung deposition. The mass median aerodynamic diameter of 2.52 ± 0.23 µm, indicates that the desired target should be reached. The inhibition of TNF-α release, as one of the main mediators of proinflammatory reactions, was investigated. We could show that our carrier system can be loaded with siRNA against TNF-α. Gel electrophoreses allowed to demonstrate that the load can be incorporated and released without being degraded. The delivery system was found to transport a mass fraction of 0.371% [%w/w] as determined by inductively coupled plasma mass spectroscopy. When investigating the release kinetics, the results showed that several days are necessary to release a major amount of the siRNA indicating a sustained release. The cylindrical microparticles with an aspect ratio of 3.3 (ratio of length divided by width) were then tested in vitro successfully reducing TNF-α release from human macrophages significantly by more than 30%. The developed formulation presents a possible oligonucleotide delivery system allowing due to its internal structure to load and protect siRNA.

The role of microRNAs in ovarian function and the transition toward novel therapeutic strategies in fertility preservation: from bench to future clinical application

BACKGROUND

New therapeutic approaches in oncology have converted cancer from a certain death sentence to a chronic disease. However, there are still challenges to be overcome regarding the off-target toxicity of many of these treatments. Oncological therapies can lead to future infertility in women. Given this negative impact on long-term quality of life, fertility preservation is highly recommended. While gamete and ovarian tissue cryopreservation are the usual methods offered, new pharmacological-based options aiming to reduce ovarian damage during oncological treatment are very attractive. In this vein, advances in the field of transcriptomics and epigenomics have brought small noncoding RNAs, called microRNAs (miRNAs), into the spotlight in oncology. MicroRNAs also play a key role in follicle development as regulators of follicular growth, atresia and steroidogenesis. They are also involved in DNA damage repair responses and they can themselves be modulated during chemotherapy. For these reasons, miRNAs may be an interesting target to develop new protective therapies during oncological treatment. This review summarizes the physiological role of miRNAs in reproduction. Considering recently developed strategies based on miRNA therapy in oncology, we highlight their potential interest as a target in fertility preservation and propose future strategies to make the transition from bench to clinic.

OBJECTIVE AND RATIONALE

How can miRNA therapeutic approaches be used to develop new adjuvant protective therapies to reduce the ovarian damage caused by cytotoxic oncological treatments?

SEARCH METHODS

A systematic search of English language literature using PubMed and Google Scholar databases was performed through to 2019 describing the role of miRNAs in the ovary and their use for diagnosis and targeted therapy in oncology. Personal data illustrate miRNA therapeutic strategies to target the gonads and reduce chemotherapy-induced follicular damage.

OUTCOMES

This review outlines the importance of miRNAs as gene regulators and emphasizes the fact that insights in oncology can inspire new adjuvant strategies in the field of onco-fertility. Recent improvements in nanotechnology offer the opportunity for drug development using next-generation miRNA-nanocarriers.

WIDER IMPLICATIONS

Although there are still some barriers regarding the immunogenicity and toxicity of these treatments and there is still room for improvement concerning the specific delivery of miRNAs into the ovaries, we believe that, in the future, miRNAs can be developed as powerful and non-invasive tools for fertility preservation.

Prospects for the potential of RNA interference in the treatment of autoimmune diseases: Small interfering RNAs in the spotlight

The identification of RNA interference (RNAi) has caused a growing interest in harnessing its potential in the treatment of different diseases. Modulation of dysregulated genes through targeting by RNAi represents a potential approach with which to alter the biological pathways at a post-transcriptional level, especially as it pertains to autoimmunity and malignancy. Short hairpin RNAs (shRNA), short interfering RNAs (siRNA), and microRNAs (miRNA) are mainly involved as effector mechanisms in the targeting of RNAi biological pathways. The manipulation and delivery of these molecules in an efficient way promotes the specificity and stability of RNAi-based systems, while minimizing the unwanted adverse reactions by the immune system and reducing cytotoxicity and off-target effects. Advances made to date in identifying the etiopathogenesis of autoimmune diseases has prompted the utilization of RNAi-based systems in vitro and in vivo. Future investigations aimed at deciphering the molecular basis of RNAi and optimizing the delivery of RNAi-based targeting systems will hopefully promote the applicability of such regulatory mechanisms and, ultimately, transfer the acquired knowledge from bench-to-bedside to ameliorate human diseases. In this review, we seek to clarify the potential of RNAi, with a focus on siRNAs, in designing therapeutics for potential treatment of human autoimmune disorders.

Development of MicroRNAs as Potential Therapeutics against Cancer

MicroRNAs (miRNAs) are small noncoding RNAs that function at the posttranscriptional level in the cellular regulation process. miRNA expression exerts vital effects on cell growth such as cell proliferation and survival. In cancers, miRNAs have been shown to initiate carcinogenesis, where overexpression of oncogenic miRNAs (oncomiRs) or reduced expression of tumor suppressor miRNAs has been reported. In this review, we discuss the involvement of miRNAs in tumorigenesis, the role of synthetic miRNAs as either mimics or antagomirs to overcome cancer growth, miRNA delivery, and approaches to enhance their therapeutic potentials.

Liposomes: Advancements and innovation in the manufacturing process

Liposomes are well recognised as effective drug delivery systems, with a range of products approved, including follow on generic products. Current manufacturing processes used to produce liposomes are generally complex multi-batch processes. Furthermore, liposome preparation processes adopted in the laboratory setting do not offer easy translation to large scale production, which may delay the development and adoption of new liposomal systems. To promote advancement and innovation in liposome manufacturing processes, this review considers the range of manufacturing processes available for liposomes, from laboratory scale and scale up, through to large-scale manufacture and evaluates their advantages and limitations. The regulatory considerations associated with the manufacture of liposomes is also discussed. New innovations that support leaner scalable technologies for liposome fabrication are outlined including self-assembling liposome systems and microfluidic production. The critical process attributes that impact on the liposome product attributes are outlined to support potential wider adoption of these innovations.

Skin Delivery of siRNA Using Sponge Spicules in Combination with Cationic Flexible Liposomes

We report the topical administration of sponge Haliclona sp. Spicules (SHS) combined with cationic flexible liposomes (CFL) to increase the delivery of small interfering RNA (siRNA) into viable skin cells in vitro and in vivo. SHS can be applied topically as novel microneedles to overcome skin barrier by creating plenty of new microchannels in stratum corneum. Subsequently, well-designed CFL can be also utilized topically as nanocarriers to overcome skin cells membrane by delivering siRNA to skin deep layers through these microchannels and thereby facilitating their cell internalization. The topical application of SHS in combination with CFL (0.05% of lipids, w/v), referred to as CFL(0.05%), enhanced siRNA skin penetration in vitro by 72.95 ± 2.97-fold compared to control group (p < 0.001). Further, the topical application of SHS in combination with CFL(0.05%) on female BALB/c mice skin resulted in 29.21% ± 1.41% of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knockdown at all application area in vivo, which was not significantly different from the GAPDH protein knockdown rate in the subcutaneous injection center. However, the high knockdown rate only appears in the vicinity (<0.5 cm) of the injection center. In sum, this study provides a promising strategy of topical delivery of siRNA by the combined used of SHS and well-designed CFL.

Targeted siRNA Delivery Using Lipid Nanoparticles

Efficient intracellular delivery of small-interfering ribonucleic acid (siRNA) to the target organ or tissues in the body is assumed as the main hurdle for a widespread use of siRNAs in the clinics. Solid lipid-based nanoparticles (SLNs) and derivatives can potentially fit this purpose by enabling to overcome the extracellular and intracellular physiological barriers affecting the delivery. For that, rational formulations and rational process designs are needed. This chapter addresses a comprehensive description and critical appraisal of the main production methods of this particular type of lipid nanoparticles and the leading strategies to prompt a targeted delivery of siRNA.

Efficient nanocarriers of siRNA therapeutics for cancer treatment

Nanocarriers as drug delivery systems are promising and becoming popular, especially for cancer treatment. In addition to improving the pharmacokinetics of poorly soluble hydrophobic drugs by solubilizing them in a hydrophobic core, nanocarriers allow cancer-specific combination drug deliveries by inherent passive targeting phenomena and adoption of active targeting strategies. Nanoparticle-drug formulations can enhance the safety, pharmacokinetic profiles, and bioavailability of locally or systemically administered drugs, leading to improved therapeutic efficacy. Gene silencing by RNA interference (RNAi) is rapidly developing as a personalized field of cancer treatment. Small interfering RNAs (siRNAs) can be used to switch off specific cancer genes, in effect, "silence the gene, silence the cancer." siRNA can be used to silence specific genes that produce harmful or abnormal proteins. The activity of siRNA can be used to harness cellular machinery to destroy a corresponding sequence of mRNA that encodes a disease-causing protein. At present, the main barrier to implementing siRNA therapies in clinical practice is the lack of an effective delivery system that protects the siRNA from nuclease degradation, delivers to it to cancer cells, and releases it into the cytoplasm of targeted cancer cells, without creating adverse effects. This review provides an overview of various nanocarrier formulations in both research and clinical applications with a focus on combinations of siRNA and chemotherapeutic drug delivery systems for the treatment of multidrug resistant cancer. The use of various nanoparticles for siRNA-drug delivery, including liposomes, polymeric nanoparticles, dendrimers, inorganic nanoparticles, exosomes, and red blood cells for targeted drug delivery in cancer is discussed.

Nanomedicine for Imaging and Therapy of Pancreatic Adenocarcinoma

Pancreatic adenocarcinoma has the worst outcome among all cancer types, with a 5-year survival rate as low as 10%. The lethal nature of this cancer is a result of its silent onset, resistance to therapies, and rapid spreading. As a result, most patients remain asymptomatic and present at diagnosis with an already infiltrating and incurable disease. The tumor microenvironment, composed of a dense stroma and of disorganized blood vessels, coupled with the dysfunctional signal pathways in tumor cells, creates a set of physical and biological barriers that make this tumor extremely hard-to-treat with traditional chemotherapy. Nanomedicine has great potential in pancreatic adenocarcinoma, because of the ability of nano-formulated drugs to overcome biological barriers and to enhance drug accumulation at the target site. Moreover, monitoring of disease progression can be achieved by combining drug delivery with imaging probes, resulting in early detection of metastatic patterns. This review describes the latest development of theranostic formulations designed to concomitantly treat and image pancreatic cancer, with a specific focus on their interaction with physical and biological barriers.

MicroRNA delivery through nanoparticles

MicroRNAs (miRNAs) are attracting a growing interest in the scientific community due to their central role in the etiology of major diseases. On the other hand, nanoparticle carriers offer unprecedented opportunities for cell specific controlled delivery of miRNAs for therapeutic purposes. This review critically discusses the use of nanoparticles for the delivery of miRNA-based therapeutics in the treatment of cancer and neurodegenerative disorders and for tissue regeneration. A fresh perspective is presented on the design and characterization of nanocarriers to accelerate translation from basic research to clinical application of miRNA-nanoparticles. Main challenges in the engineering of miRNA-loaded nanoparticles are discussed, and key application examples are highlighted to underline their therapeutic potential for effective and personalized medicine.

MicroRNA as novel biomarkers and therapeutic targets in diabetic kidney disease: An update

Diabetic kidney disease (DKD) is a life-limiting condition characterized by progressive and irreversible loss of renal function. Currently, the estimated glomerular filtration rate (eGFR) and albuminuria are used as key markers to define DKD. However, they may not accurately indicate the degree of renal dysfunction and injury. Current therapeutic approaches for DKD, including attainment of blood pressure goals, optimal control of blood glucose and lipid levels, and the use of agents to block the renin-angiotensin-aldosterone system (RAAS) can only slow the progression of DKD. Hence, early diagnosis and innovative strategies are needed to both prevent and treat DKD. In recent years, a novel class of noncoding RNA, microRNAs (miRNAs) are reported to be involved in all biological processes, including cellular proliferation, apoptosis, and differentiation. miRNAs are small noncoding RNAs that regulate gene expression by posttranscriptional and epigenetic mechanisms. They are found to be in virtually all body fluids and used successfully as biomarkers for various diseases. Urinary miRNAs correlate with clinical and histologic parameters in DKD and differential urinary miRNA expression patterns have been reported. Kidney fibrosis is the common end stage of various CKD including DKD. Transforming growth factor-β(TGF-β) is regarded as the master regulator of kidney fibrosis, which is likely at least in part through regulating miRNA expression. miRNA are widely involved in the progression of DKD via many molecular mechanisms. In this review, the involvement of miRNA in fibrosis, inflammation, hypertrophy, autophagy, endoplasmic reticulum (ER) stress, oxidative stress, insulin resistance, and podocyte injury will be discussed, as these mechanisms are believed to offer new therapeutic targets that can be exploited to develop important treatments for DKD over the next decade.

Tackling Aging by Using miRNA as a Target and a Tool

miRNA is a class of short noncoding RNA that regulates gene expression at the post-transcriptional level. Evidence of age-associated changes in miRNA expression has been collected in models ranging from nematodes to humans; however, there has been little discussion of how to turn our knowledge of miRNA biology into antiaging therapy. This opinion article provides a snapshot of our current understanding of the roles of miRNA in modulating the aging process. We discuss major chemical techniques for modifying the miRNA structure as well as developing delivery systems for intervention. Finally, technical needs to be met for bench-to-clinic translation of miRNA-based interventions are highlighted for future research.

MicroRNA replacement therapy in cancer

Despite the recent progress in cancer management approaches, the mortality rate of cancer is still growing and there are lots of challenges in the clinics in terms of novel therapeutics. MicroRNAs (miRNA) are regulatory small noncoding RNAs and are already confirmed to have a great role in regulating gene expression level by targeting multiple molecules that affect cell physiology and disease development. Recently, miRNAs have been introduced as promising therapeutic targets for cancer treatment. Regulatory potential of tumor suppressor miRNAs, which enables regulation of entire signaling networks within the cells, makes them an interesting option for developing cancer therapeutics. In this regard, over recent decades, scientists have aimed at developing powerful and safe targeting approaches to restore these suppressive miRNAs in cancerous cells. The present review summarizes the function of miRNAs in tumor development and presents recent findings on how miRNAs have served as therapeutic agents against cancer, with a special focus on tumor suppressor miRNAs (mimics). Moreover, the latest investigations on the therapeutic strategies of miRNA delivery have been presented.

Reprogramming Cells for Synergistic Combination Therapy with Nanotherapeutics against Uveal Melanoma

Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults and around half of the patients develop metastasis and die shortly after because of the lack of effective therapies for metastatic UM. Consequently, new therapeutic approaches to this disease are welcome. In this regard, microRNAs have been shown to have a key role in neoplasia progression and have the potential to be used as therapeutic tools. In addition, in different cancers including UM, a particular microRNA signature appears that is different from healthy cells. Thus, restoring the regular levels of microRNAs could restore the normal behavior of cells. In this study, four microRNAs downregulated in UM have been chosen to reprogram cancer cells, to promote cell death or increase their sensitivity to the chemotherapeutic SN38. Furthermore, to improve the internalization, stability and/or solubility of the therapeutic molecules employed in this approach, gold nanoparticles (AuNPs) were used as carriers. Remarkably, this study found a synergistic effect when the four oligonucleotides were employed and when the chemotherapeutic drug was added.

Gemcitabine-Incorporated G-Quadruplex Aptamer for Targeted Drug Delivery into Pancreas Cancer

Gemcitabine has been considered a first-line chemotherapy agent for the treatment of pancreatic cancer. However, the initial response rate of gemcitabine is low and chemoresistance occurs frequently. Aptamers can be effectively internalized into cancer cells via binding to target molecules with high affinity and specificity. In the current study, we constructed an aptamer-based gemcitabine delivery system, APTA-12, and assessed its therapeutic effects on pancreatic cancer cells in vitro and in vivo. APTA-12 was effective in vitro and in vivo in pancreatic cancer cells with high expression of nucleolin. The results of in vitro cytotoxicity assays indicated that APTA-12 inhibited the growth of pancreatic cancer cell lines. In vivo evaluation showed that APTA-12 effectively inhibited the growth of pancreatic cancer in Capan-1 tumor-bearing mice compared to mice that received gemcitabine alone or vehicle. These results suggest that the gemcitabine-incorporated APTA-12 aptamer may be a promising targeted therapeutic strategy for pancreatic cancer.

Recent applications of the combination of mesoporous silica nanoparticles with nucleic acids: development of bioresponsive devices, carriers and sensors

The discovery and control of the biological roles mediated by nucleic acids have turned them into a powerful tool for the development of advanced biotechnological materials. Such is the importance of these gene-keeping biomacromolecules that even nanomaterials have succumbed to the claimed benefits of DNA and RNA. Currently, there could be found in the literature a practically intractable number of examples reporting the use of combination of nanoparticles with nucleic acids, so boundaries are demanded. Following this premise, this review will only cover the most recent and powerful strategies developed to exploit the possibilities of nucleic acids as biotechnological materials when in combination with mesoporous silica nanoparticles. The extensive research done on nucleic acids has significantly incremented the technological possibilities for those biomacromolecules, which could be employed in many different applications, where substrate or sequence recognition or modulation of biological pathways due to its coding role in living cells are the most promising. In the present review, the chosen counterpart, mesoporous silica nanoparticles, also with unique properties, became a reference material for drug delivery and biomedical applications due to their high biocompatibility and porous structure suitable for hosting and delivering small molecules. Although most of the reviews dealt with significant advances in the use of nucleic acid and mesoporous silica nanoparticles in biotechnological applications, a rational classification of these new generation hybrid materials is still uncovered. In this review, there will be covered promising strategies for the development of living cell and biological sensors, DNA-based molecular gates with targeting, transfection or silencing properties, which could provide a significant advance in current nanomedicine.

Selection and Characterization of a DNA Aptamer Specifically Targeting Human HECT Ubiquitin Ligase WWP1

Nucleic acid aptamers hold promise as therapeutic tools for specific, tailored inhibition of protein targets with several advantages when compared to small molecules or antibodies. Nuclear WW domain containing E3 ubiquitin ligase 1 (WWP1) ubiquitin ligase poly-ubiquitinates Runt-related transcription factor 2 (Runx2), a key transcription factor associated with osteoblast differentiation. Since WWP1 and an adapter known as Schnurri-3 are negative regulators of osteoblast function, the disruption of this complex has the potential to increase bone deposition for osteoporosis therapy. Here, we develop new DNA aptamers that bind and inhibit WWP1 then investigate efficacy in an osteoblastic cell culture. DNA aptamers were selected against three different truncations of the HECT domain of WWP1. Aptamers which bind specifically to a C-lobe HECT domain truncation were observed to enrich during the selection procedure. One particular DNA aptamer termed C3A was further evaluated for its ability to bind WWP1 and inhibit its ubiquitination activity. C3A showed a low µM binding affinity to WWP1 and was observed to be a non-competitive inhibitor of WWP1 HECT ubiquitin ligase activity. When SaOS-2 osteoblastic cells were treated with C3A, partial localization to the nucleus was observed. The C3A aptamer was also demonstrated to specifically promote extracellular mineralization in cell culture experiments. The C3A aptamer has potential for further development as a novel osteoporosis therapeutic strategy. Our results demonstrate that aptamer-mediated inhibition of protein ubiquitination can be a novel therapeutic strategy.

Selection and Identification of Skeletal-Muscle-Targeted RNA Aptamers

Oligonucleotide gene therapy has shown great promise for the treatment of muscular dystrophies. Nevertheless, the selective delivery to affected muscles has shown to be challenging because of their high representation in the body and the high complexity of their cell membranes. Current trials show loss of therapeutic molecules to non-target tissues leading to lower target efficacy. Therefore, strategies that increase uptake efficiency would be particularly compelling. To address this need, we applied a cell-internalization SELEX (Systematic Evolution of Ligands by Exponential Enrichment) approach and identified a skeletal muscle-specific RNA aptamer. A01B RNA aptamer preferentially internalizes in skeletal muscle cells and exhibits decreased affinity for off-target cells. Moreover, this in vitro selected aptamer retained its functionality in vivo, suggesting a potential new approach for targeting skeletal muscles. Ultimately, this will aid in the development of targeted oligonucleotide therapies against muscular dystrophies.

Delivery of Antioxidant and Anti-inflammatory Agents for Tissue Engineered Vascular Grafts

The treatment of patients with severe coronary and peripheral artery disease represents a significant clinical need, especially for those patients that require a bypass graft and do not have viable veins for autologous grafting. Tissue engineering is being investigated to generate an alternative graft. While tissue engineering requires surgical intervention, the release of pharmacological agents is also an important part of many tissue engineering strategies. Delivery of these agents offers the potential to overcome the major concerns for graft patency and viability. These concerns are related to an extended inflammatory response and its impact on vascular cells such as endothelial cells. This review discusses the drugs that have been released from vascular tissue engineering scaffolds and some of the non-traditional ways that the drugs are presented to the cells. The impact of antioxidant compounds and gasotransmitters, such as nitric oxide and carbon monoxide, are discussed in detail. The application of tissue engineering and drug delivery principles to biodegradable stents is also briefly discussed. Overall, there are scaffold-based drug delivery techniques that have shown promise for vascular tissue engineering, but much of this work is in the early stages and there are still opportunities to incorporate additional drugs to modulate the inflammatory process.

Gene delivery nanoparticles to modulate angiogenesis

Angiogenesis is naturally balanced by many pro- and anti-angiogenic factors while an imbalance of these factors leads to aberrant angiogenesis, which is closely associated with many diseases. Gene therapy has become a promising strategy for the treatment of such a disordered state through the introduction of exogenous nucleic acids that express or silence the target agents, thereby engineering neovascularization in both directions. Numerous non-viral gene delivery nanoparticles have been investigated towards this goal, but their clinical translation has been hampered by issues associated with safety, delivery efficiency, and therapeutic effect. This review summarizes key factors targeted for therapeutic angiogenesis and anti-angiogenesis gene therapy, non-viral nanoparticle-mediated approaches to gene delivery, and recent gene therapy applications in pre-clinical and clinical trials for ischemia, tissue regeneration, cancer, and wet age-related macular degeneration. Enhanced nanoparticle design strategies are also proposed to further improve the efficacy of gene delivery nanoparticles to modulate angiogenesis.

The Role of miRNAs in Angiogenesis, Invasion and Metabolism and Their Therapeutic Implications in Gliomas

MicroRNAs (miRNAs) are small, non-coding, endogenous RNA molecules that function in gene silencing by post-transcriptional regulation of gene expression. The dysregulation of miRNA plays a pivotal role in cancer tumorigenesis, including the development and progression of gliomas. Their small size, stability and ability to target multiple oncogenes have simultaneously distinguished miRNAs as attractive candidates for biomarkers and novel therapeutic targets for glioma patients. In this review, we summarize the most frequently cited miRNAs known to contribute to gliomagenesis and progression by regulating the defining hallmarks of gliomas, including angiogenesis, invasion, and cell metabolism. We also discuss their promising potential as prognostic and predictive biomarkers and novel therapeutic targets, in addition to the challenges that must be overcome before their translation from bench to bedside.

In vitro 3D model and miRNA drug delivery to target calcific aortic valve disease

Calcific aortic valve disease (CAVD) is the most prevalent valvular heart disease in the Western population, claiming 17000 deaths per year in the United States and affecting 25% of people older than 65 years of age. Contrary to traditional belief, CAVD is not a passive, degenerative disease but rather a dynamic disease, where initial cellular changes in the valve leaflets progress into fibrotic lesions that induce valve thickening and calcification. Advanced thickening and calcification impair valve function and lead to aortic stenosis (AS). Without intervention, progressive ventricular hypertrophy ensues, which ultimately results in heart failure and death. Currently, aortic valve replacement (AVR), surgical or transcatheter, is the only effective therapy to treat CAVD. However, these costly interventions are often delayed until the late stages of the disease. Nonetheless, 275000 are performed per year worldwide, and this is expected to triple by 2050. Given the current landscape, next-generation therapies for CAVD are needed to improve patient outcome and quality of life. Here, we first provide a background on the aortic valve (AV) and the pathobiology of CAVD as well as highlight current directions and future outlook on the development of functional 3D models of CAVD in vitro We then consider an often-overlooked aspect contributing to CAVD: miRNA (mis)regulation. Therapeutics could potentially normalize miRNA levels in the early stages of the disease and may slow its progression or even reverse calcification. We close with a discussion of strategies that would enable the use of miRNA as a therapeutic for CAVD. This focuses on an overview of controlled delivery technologies for nucleic acid therapeutics to the valve or other target tissues.

Stimuli-Responsive Mesoporous Silica NPs as Non-viral Dual siRNA/Chemotherapy Carriers for Triple Negative Breast Cancer

Triple negative breast cancer (TNBC) is the most aggressive and lethal subtype of breast cancer. It is associated with a very poor prognosis and intrinsically resistant to several conventional and targeted chemotherapy agents and has a 5-year survival rate of less than 25%. Because the treatment options for TNBC are very limited and not efficient enough for achieving minimum desired goals, shifting toward a new generation of anti-cancer agents appears to be very critical. Among recent alternative approaches being proposed, small interfering RNA (siRNA) gene therapy can potently suppress Bcl-2 proto-oncogene and p-glycoprotein gene expression, the most important chemotherapy resistance inducers in TNBC. When resensitized, primarily ineffective chemotherapy drugs turn back into valuable sources for further intensive chemotherapy. Regrettably, siRNA's poor stability, rapid clearance in the circulatory system, and poor cellular uptake mostly hampers the beneficial outcomes of siRNA therapy. Considering these drawbacks, dual siRNA/chemotherapy drug encapsulation in targeted delivery vehicles, especially mesoporous silica nanoparticles (MSNs) appears to be the most reasonable solution. The literature is full of reports of successful treatments of multi-drug-resistant cancer cells by administration of dual drug/siRNA-loaded MSNs. Here we tried to answer the question of whether application of a similar approach with identical delivery devices in TNBC is rational.

Can colorectal delivery technology provide a platform for enteral oligonucleotide-based therapeutics?

Nucleic acid-based therapeutics including antisense and siRNA oligonucleotides has been expected as an innovative treatment for intractable diseases. Oral drug delivery is the most patient-friendly route of administration but developing an effective delivery system for oligonucleotides remains a major challenge. In this commentary, we discuss the potential benefits of the colorectal route as another platform for the development of oral oligonucleotide therapeutics. The importance of the targeting or the availability of oligonucleotides in targeted tissue is highlighted in contrast to systemic availability, while the liver-targeted enteral siRNA delivery technology that we recently developed is introduced.

Antihyperalgesic effect of CB1 receptor activation involves the modulation of P2X3 receptor in the primary afferent neuron

Cannabinoid system is a potential target for pain control. Cannabinoid receptor 1 (CB₁) activation play a role in the analgesic effect of cannabinoids once it is expressed in primary afferent neurons. This study investigates whether the anti-hyperalgesic effect of CB₁ receptor activation involves P2X₃ receptor in primary afferent neurons. Mechanical hyperalgesia was evaluated by electronic von Frey test. Cannabinoid effect was evaluated using anandamide or ACEA, a non-selective or a selective CB₁ receptor agonists, respectively; AM251, a CB₁ receptor antagonist, and antisense ODN for CB₁ receptor. Calcium imaging assay was performed to evaluated α,β-meATP-responsive cultured DRG neurons pretreated with ACEA. Anandamide or ACEA administered in peripheral tissue reduced the carrageenan-induced mechanical hyperalgesia. The reduction in the carrageenan-induced hyperalgesia induced by ACEA was completely reversed by administration of AM251 as well as by the intrathecal treatment with antisense ODN for CB₁ receptor. Also, ACEA reduced the mechanical hyperalgesia induced by bradykinin and by α,β-meATP, a P2X₃ receptor non-selective agonist, but not by tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β) and chemokine-induced chemoattractant-1 (CINC-1). Finally, CB₁ receptors are co-localized with P2X₃ receptors in DRG small-diameter neurons and the treatment with ACEA reduced the number of α,β-meATP-responsive cultured DRG neurons. Our data suggest that the analgesic effect of CB₁ receptor activation is mediated by a negative modulation of the P2X₃ receptor in the primary afferent neurons.

Size Specific Transfection to Mammalian Cells by Micropillar Array Electroporation

Electroporation serves as a promising non-viral gene delivery approach, while its current configuration carries several drawbacks associated with high-voltage electrical pulses and heterogeneous treatment on individual cells. Here we developed a new micropillar array electroporation (MAE) platform to advance the electroporation-based delivery of DNA and RNA probes into mammalian cells. By introducing well-patterned micropillar array texture on the electrode surface, the number of pillars each cell faces varies with its plasma membrane surface area, despite their large population and random locations. In this way, cell size specific electroporation is conveniently carried out, contributing to a 2.5~3 fold increase on plasmid DNA transfection and an additional 10–55% transgene knockdown with siRNA probes, respectively. The delivery efficiency varies with the number and size of micropillars as well as their pattern density. As MAE works like many single cell electroporation are carried out in parallel, the electrophysiology response of individual cells is representative, which has potentials to facilitate the tedious, cell-specific protocol screening process in current bulk electroporation (i.e., electroporation to a large population of cells). Its success might promote the wide adoption of electroporation as a safe and effective non-viral gene delivery approach needed in many biological research and clinical treatments.