A highly efficient synthetic vector: nonhydrodynamic delivery of DNA to hepatocyte nuclei in vivo

Amplifying Ca2+ overload by engineered biomaterials for synergistic cancer therapy

Ca2+ overload is one of the most widely causes of inducing apoptosis, pyroptosis, immunogenic cell death, autophagy, paraptosis, necroptosis, and calcification of tumor cells, and has become the most valuable therapeutic strategy in the field of cancer treatment. Nevertheless, several challenges remain in translating Ca2+ overload-mediated therapeutic strategies into clinical applications, such as the precise control of Ca2+ dynamics, specificity of Ca2+ homeostasis dysregulation, as well as comprehensive mechanisms of Ca2+ regulation. Given this, we comprehensively reviewed the Ca2+-driven intracellular signaling pathways and the application of Ca2+-based biomaterials (such as CaCO3-, CaP-, CaO2-, CaSi-, CaF2-, and CaH2-) in mediating cancer diagnosis, treatment, and immunotherapy. Meanwhile, the latest researches on Ca2+ overload-mediated therapeutic strategies, as well as those combined with multiple-model therapies in mediating cancer immunotherapy are further highlighted. More importantly, the critical challenges and the future prospects of the Ca2+ overload-mediated therapeutic strategies are also discussed. By consolidating recent findings and identifying future research directions, this review aimed to advance the field of oncology therapy and contribute to the development of more effective and targeted treatment modalities.

Rubicon siRNA-encapsulated liver-targeting nanoliposome is a promising therapeutic for non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a prevalent metabolic liver disorder worldwide, and effective therapeutic strategies for its treatment remains limited. In this article, we introduced Glipo-siRubi, a hepatocytes-targeting RNA interference (RNAi) nanoliposome for suppression of Rubicon expression, aiming to achieve precise regulation of autophagy in NAFLD. Autophagy activation induced by Rubicon suppression resulted in reduced endoplasmic reticulum stress and intracellular lipid accumulation in vitro. Moreover, Glipo-siRubi administration exhibited remarkable therapeutic efficacy, characterized by decreased liver lipid accumulation, ameliorated histopathology and improved insulin sensitivity in mice with western diet, indicating its notable potential against NAFLD. By inducing autophagy activation, the hepatocytes-targeting Glipo-siRubi provided a promising method for NAFLD treatment, addressing the limitations of current approaches. Our study highlighted the significance of Rubicon-specific suppression in NAFLD treatment, offering a specific, safe, and efficient approach to mitigate NAFLD.

Impact of Small Tumor Size on Prognosis in T3N1 Colon Cancer

BACKGROUND

Traditionally, large tumor size is associated with poor survival in colon cancer, but its impact remains limited and controversial. Recently, the impact of small tumor size on prognosis has gained attention. This study aimed to investigate whether small tumor size can be an additional parameter for T3N1 colon cancer prognosis.

METHODS

We retrospectively analyzed 162 consecutive patients with pT3N1 colon cancer between 2010 and 2021. The optimal cutoff value of tumor size was calculated through receiver operating characteristic curve analysis. We evaluated survival through the Kaplan-Meier method, and the risk of prognosis through multivariate Cox models.

RESULTS

The optimal cutoff value of tumor size was 45 mm. The recurrence rate was significantly higher in tumor size < 45 mm than in ≥ 45 mm (25.7% vs. 12.0%, p = 0.037). Tumor size < 45 mm also had lower overall survival (OS), recurrence-free survival (RFS), and cancer-specific survival (CSS) than its counterpart (p = 0.03 for all). In multivariate analyses, age ≥ 70 years, undifferentiated histological type, and tumor size < 45 mm were independent prognostic factors for OS (p = 0.025, p = 0.001, p < 0.04, respectively), whereas tumor size < 45 mm was the only independent prognostic factor for RFS (p = 0.043). Meanwhile, the independent prognostic factors for CSS were undifferentiated histological type and tumor size < 45 mm (p = 0.008 for both).

CONCLUSIONS

Small tumor size is associated with poor prognosis in pT3N1 colon cancer cases. Thus, small tumors potentially have biologically aggressive features.

Navigating the intricate in-vivo journey of lipid nanoparticles tailored for the targeted delivery of RNA therapeutics: a quality-by-design approach

RNA therapeutics, such as mRNA, siRNA, and CRISPR-Cas9, present exciting avenues for treating diverse diseases. However, their potential is commonly hindered by vulnerability to degradation and poor cellular uptake, requiring effective delivery systems. Lipid nanoparticles (LNPs) have emerged as a leading choice for in vivo RNA delivery, offering protection against degradation, enhanced cellular uptake, and facilitation of endosomal escape. However, LNPs encounter numerous challenges for targeted RNA delivery in vivo, demanding advanced particle engineering, surface functionalization with targeting ligands, and a profound comprehension of the biological milieu in which they function. This review explores the structural and physicochemical characteristics of LNPs, in-vivo fate, and customization for RNA therapeutics. We highlight the quality-by-design (QbD) approach for targeted delivery beyond the liver, focusing on biodistribution, immunogenicity, and toxicity. In addition, we explored the current challenges and strategies associated with LNPs for in-vivo RNA delivery, such as ensuring repeated-dose efficacy, safety, and tissue-specific gene delivery. Furthermore, we provide insights into the current clinical applications in various classes of diseases and finally prospects of LNPs in RNA therapeutics.

Lipid-nanoparticle-enabled nucleic acid therapeutics for liver disorders

Inherited genetic disorders of the liver pose a significant public health burden. Liver transplantation is often limited by the availability of donor livers and the exorbitant costs of immunosuppressive therapy. To overcome these limitations, nucleic acid therapy provides a hopeful alternative that enables gene repair, gene supplementation, and gene silencing with suitable vectors. Though viral vectors are the most efficient and preferred for gene therapy, pre-existing immunity debilitating immune responses limit their use. As a potential alternative, lipid nanoparticle-mediated vectors are being explored to deliver multiple nucleic acid forms, including pDNA, mRNA, siRNA, and proteins. Herein, we discuss the broader applications of lipid nanoparticles, from protein replacement therapy to restoring the disease mechanism through nucleic acid delivery and gene editing, as well as multiple preclinical and clinical studies as a potential alternative to liver transplantation.

Nuclear localization signal-tagged systems: relevant nuclear import principles in the context of current therapeutic design

Nuclear targeting of therapeutics provides a strategy for enhancing efficacy of molecules active in the nucleus and minimizing off-target effects. 'Active' nuclear-directed transport and efficient translocations across nuclear pore complexes provide the most effective means of maximizing nuclear localization. Nuclear-targeting systems based on nuclear localization signal (NLS) motifs have progressed significantly since the beginning of the current millennium. Here, we offer a roadmap for understanding the basic mechanisms of nuclear import in the context of actionable therapeutic design for developing NLS-therapeutics with improved treatment efficacy.

Lactosylated lipid calcium phosphate-based nanoparticles: A promising approach for efficient DNA delivery to hepatocytes

Objectives

For safe and effective gene therapy, the ability to deliver the therapeutic nucleic acid to the target sites is crucial. In this study, lactosylated lipid phosphate calcium nanoparticles (lac-LCP) were developed for targeted delivery of pDNA to the hepatocyte cells. The lac-LCP formulation contained lactose-modified cholesterol (CHL), a ligand that binds to the asialoglycoprotein receptor (ASGR) expressed on hepatocytes, and polyethyleneimine (PEI) in the core.

Materials and Methods

Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) were used to monitor the chemical modification, and the physicochemical properties of NPs were studied using dynamic light scattering (DLS) and transmission electron microscopy (TEM). To evaluate transfection efficiency, cellular uptake and GFP expression were assessed using fluorescence microscopy and flow cytometry.

Results

The results revealed that lactose-targeted particles (lac-LCP) had a significant increase in cellular uptake by hepatocytes. The inclusion of a low molecular weight PEI (1.8 KDa) with a low PEI/pDNA ratio of 1 in the core of LCP, elicited high degrees of GFP protein expression (by 5 and 6-fold), which exhibited significantly higher efficiency than PEI 1.8 KDa and Lipofectamine.

Conclusion

The successful functionalization and nuclear delivery of LCP NPs described here indicate its promise as an efficient delivery vector to hepatocyte nuclei.

Bioresponsive Chimaeric Polymersomes Mediate Sustained and Liver-Specific siRNA Transfection In Vivo

The silencing of disease-causing genes with small interfering RNA (siRNA) offers a particularly effective therapeutic strategy for different disorders; however, its clinical efficacy relies on the development of nontoxic and tissue-specific delivery vehicles. Herein, we report that bioresponsive chimaeric polymersomes (BCP) with short poly(ethylenimine) as inner shell mediate highly efficacious, sustained, and liver-specific siRNA transfection in vivo. BCP exhibited remarkable encapsulation efficiencies of siRNA (95-100%) at siRNA-feeding contents of 15-25 wt %, to afford stable, small-sized (55-64 nm), and neutral-charged BCP-siRNA. siApoB-Loaded BCP (BCP-siApoB) outperformed lipofectamine counterparts and silenced 93% of ApoB mRNA in HepG2 cells at 50 nM siApoB without inducing cytotoxicity. Intriguingly, the in vivo studies using wild-type C57BL/6 mice revealed that BCP-siApoB preferentially accumulated in the liver, and a single dose of 4.5 mg/kg achieved over 90% downregulation of ApoB mRNA for at least 10 days. The systemic administration of BCP-siApoB at 4.5 mg/kg every 2 weeks or 1.5 mg/kg weekly in diet-induced obese mice could also achieve up to 80% silencing of ApoB mRNA. The liver specificity and silencing efficacy of BCP-siApoB could further be improved by decorating it with the trivalent N-acetylgalactosamine (TriGalNAc) ligand. These bioresponsive and liver-specific chimaeric polymersomes provide an enabling technology for siRNA therapy of various liver-related diseases.

Self-Assembly of Peptide-Lipid Nanoparticles for the Efficient Delivery of Nucleic Acids

A transfection formulation is successfully developed to deliver nucleic acids by adding an auxiliary lipid (DOTAP) to the peptide, and the transfection efficiency of pDNA reaches 72.6%, which is close to Lipofectamine 2000. In addition, the designed KHL peptide-DOTAP complex exhibits good biocompatibility by cytotoxicity and hemolysis analysis. The mRNA delivery experiment indicates that the complex had a 9- or 10-fold increase compared with KHL or DOTAP alone. Intracellular localization shows that KHL/DOTAP can achieve good endolysosomal escape. Our design provides a new platform for improving the transfection efficiency of peptide vectors.

Acidification-Induced Structure Evolution of Lipid Nanoparticles Correlates with Their In Vitro Gene Transfections

The rational design of lipid nanoparticles (LNPs) for enhanced gene delivery remains challenging because of incomplete knowledge of their formulation-structure relationship that impacts their intracellular behavior and consequent function. Small-angle neutron scattering has been used in this work to investigate the structure of LNPs encapsulating plasmid DNA upon their acidification (from pH 7.4 to 4.0), as would be encountered during endocytosis. The results revealed the acidification-induced structure evolution (AISE) of the LNPs on different dimension scales, involving protonation of the ionizable lipid, volume expansion and redistribution of aqueous and lipid components. A similarity analysis using an LNP's structural feature space showed a strong positive correlation between function (measured by intracellular luciferase expression) and the extent of AISE, which was further enhanced by the fraction of unsaturated helper lipid. Our findings reveal molecular and nanoscale changes occurring during AISE that underpin the LNPs' formulation-nanostructure-function relationship, aiding the rational design of application-directed gene delivery vehicles.

A Precipitation-Enhanced Emission (PEE) Strategy for Increasing the Brightness and Reducing the Liver Retention of NIR-II Fluorophores

The lack of organic fluorophores with high quantum yields (QYs) and low liver retention in the second near-infrared (NIR-II) window has become a bottleneck in the bioimaging field. An approach to address these problems is proposed by encapsulating phosphorylated fluorescent dyes into biodegradable calcium phosphate nanoparticles. First, an NIR-II molecule, LJ-2P, is designed with increased water solubility by introducing two phosphate groups. Meanwhile, LJ-2P co-precipitates with calcium ions to form LJ-2P nanoparticles (NPs). The QYs of LJ-2P NPs in aqueous solution is increased by 36.57-fold to 5.12% compared with that of LJ-2P. This unique phenomenon is named as precipitation-enhanced emission (PEE), whose detailed mechanism is explored by femtosecond transient absorption. It is demonstrated that co-precipitation of LJ-2P with calcium ions changes the micro-environment, which restricts the molecular rotation and reduces the interaction of water molecules, especially the excited-state proton transfer. In addition, due to the pH-sensitive nature, more than 80% of the LJ-2P NPs are metabolized in the liver within 24 h. Based on the excellent optical properties and good biocompatibility, high-contrast vascular visualization and breast tumor detecting are achieved. This strategy can apply to other NIR-II fluorophores to achieve high QYs and low liver retention.

Nanotechnology-enabled immunoengineering approaches to advance therapeutic applications

Immunotherapy has reached clinical success in the last decade, with the emergence of new and effective treatments such as checkpoint blockade therapy and CAR T-cell therapy that have drastically improved patient outcomes. Still, these therapies can be improved to limit off-target effects, mitigate systemic toxicities, and increase overall efficacies. Nanoscale engineering offers strategies that enable researchers to attain these goals through the manipulation of immune cell functions, such as enhancing immunity against cancers and pathogens, controlling the site of immune response, and promoting tolerance via the delivery of small molecule drugs or biologics. By tuning the properties of the nanomaterials, such as size, shape, charge, and surface chemistry, different types of immune cells can be targeted and engineered, such as dendritic cells for immunization, or T cells for promoting adaptive immunity. Researchers have come to better understand the critical role the immune system plays in the progression of pathologies besides cancer, and developing nanoengineering approaches that seek to harness the potential of immune cell activities can lead to favorable outcomes for the treatment of injuries and diseases.

A Review of Brain-Targeted Nonviral Gene-Based Therapies for the Treatment of Alzheimer's Disease

Diseases of the central nervous system (CNS) are difficult to treat owing to the complexity of the brain and the presence of a natural blood-brain-barrier (BBB). Alzheimer's disease (AD) is one of the major progressive and currently incurable neurodegenerative disorders of the CNS, which accounts for 60-80% of cases of dementia. The pathophysiology of AD involves the accumulation of amyloid beta (Aβ) plaques and neurofibrillary tangles (NFTs) in the brain. Additionally, synaptic loss and imbalance of neuronal signaling molecules are characterized as important markers of AD. Existing treatments of AD help in the management of its symptoms and aim toward the maintenance of cognitive functions, behavior, and attenuation of gradual memory loss. Over the past decade, nonviral gene therapy has attracted increasing interest due to its various advantages over its viral counterparts. Moreover, advancements in nonviral gene technology have led to their increasing contributions in clinical trials. However, brain-targeted nonviral gene delivery vectors come across various extracellular and intracellular barriers, limiting their ability to transfer the therapeutic gene into the target cells. Chief barriers to nonviral gene therapy have been discussed briefly in this review. We have also highlighted the rapid advancement of several nonviral gene therapies for AD, which are broadly categorized into physical and chemical methods. These methods aim to modulate Aβ, beta-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1), apolipoprotein E, or neurotrophic factors' expression in the CNS. Overall, this review discusses challenges and recent advancements of nonviral gene therapy for AD.

Ultrasound image-guided gene delivery using three-dimensional diagnostic ultrasound and lipid-based microbubbles

Gene therapy is a promising technology for genetic and intractable diseases. Drug delivery carriers or systems for genes and nucleic acids have been studied to improve transfection efficiency and achieve sufficient therapeutic effects. Ultrasound (US) and microbubbles have also been combined for use in gene delivery. To establish a clinically effective gene delivery system, exposing the target tissues to US is important. The three-dimensional (3D) diagnostic probe can three-dimensionally scan the tissue with mechanical regulation, and homogenous US exposure to the targeted tissue can be expected. However, the feasibility of therapeutically applying 3D probes has not been evaluated, especially gene delivery. In this study, we evaluated the characteristics of a 3D probe and lipid-based microbubbles (LB) for gene delivery and determined whether the 3D probe in the diagnostic US device could be used for efficient gene delivery to the targeted tissue using a mouse model. The 3D probe RSP6-16 with LB delivered plasmid DNA (pDNA) to the kidney after systemic injection with luciferase activity similar to that of probes used in previously studies. No toxicity was observed after treatment and, therefore, the combined 3D probe and LB would deliver genes to targeted tissue safely and efficiently.

Understanding In Vivo Fate of Nucleic Acid and Gene Medicines for the Rational Design of Drugs

Nucleic acid and genetic medicines are increasingly being developed, owing to their potential to treat a variety of intractable diseases. A comprehensive understanding of the in vivo fate of these agents is vital for the rational design, discovery, and fast and straightforward development of the drugs. In case of intravascular administration of nucleic acids and genetic medicines, interaction with blood components, especially plasma proteins, is unavoidable. However, on the flip side, such interaction can be utilized wisely to manipulate the pharmacokinetics of the agents. In other words, plasma protein binding can help in suppressing the elimination of nucleic acids from the blood stream and deliver naked oligonucleotides and gene carriers into target cells. To control the distribution of these agents in the body, the ligand conjugation method is widely applied. It is also important to understand intracellular localization. In this context, endocytosis pathway, endosomal escape, and nuclear transport should be considered and discussed. Encapsulated nucleic acids and genes must be dissociated from the carriers to exert their activity. In this review, we summarize the in vivo fate of nucleic acid and gene medicines and provide guidelines for the rational design of drugs.

GALA-Modified Lipid Nanoparticles for the Targeted Delivery of Plasmid DNA to the Lungs

This study describes the development of lipid nanoparticles (LNPs) for the efficient and selective delivery of plasmid DNA (pDNA) to the lungs. The GALA peptide was used as a ligand to target the lung endothelium and as an endosomal escape device. Transfection activity in the lungs was significantly improved when pDNA was encapsulated in double-coated LNPs. The inner coat was composed of dioleoylphsophoethanolamine and a stearylated octaarginine (STR-R8) peptide, while the outer coat was largely a cationic lipid, di-octadecenyl-trimethylammonium propane, mixed with YSK05, a pH-sensitive lipid, and cholesterol. Optimized amounts of YSK05 and GALA were used to achieve an efficient and lung-selective system. The optimized system produced a high gene expression level in the lungs (>10⁷ RLU/mg protein) with high lung/liver and lung/spleen ratios. GALA/R8 modification and the double-coating design were indispensable for efficient gene expression in the lungs. Despite the fact that NPs prepared with 1-step or 2-step coating have the same lipid amount and composition and the same pDNA dose, the transfection activity was dramatically higher in the lungs in the case of 2-step coating. Surprisingly, 1-step or 2-step coatings had no effect on the amount of nanoparticles that were delivered to the lungs, suggesting that the double-coating strategy substantially improved the efficiency of gene expression at the intracellular level.

Synthetic multi-layer nanoparticles for CRISPR-Cas9 genome editing

The clustered regularly interspaced short palindromic repeat (CRISPR) has great potential to revolutionize biomedical research and disease therapy. The specific and efficient genome editing strongly depends on high efficiency of delivery of the CRISPR payloads. However, optimization of CRISPR delivery vehicles still remains a major obstacle. Recently, various non-viral vectors have been utilized to deliver CRISPR tools. Many of these vectors have multi-layer structures assembled. In this review, we will introduce the development of CRISPR-Cas9 systems and their general therapeutic applications by summarizing current CRISPR-Cas9 based clinical trials. We will highlight the multi-layer nanoparticles (NPs) that have been developed to deliver CRISPR cargos in vitro and in vivo for various purposes, as well the potential building blocks of multi-layer NPs. We will also discuss the challenges in making the CRISPR tools into viable pharmaceutical products and provide potential solutions on efficiency and biosafety issues.

A novel dual-targeted rosiglitazone-loaded nanoparticle for the prevention of diet-induced obesity via the browning of white adipose tissue

Adipose tissue in the body is classified as white adipose tissue (WAT); a fat-accumulating tissue, or brown adipose tissue (BAT); an energy-dissipating tissue. Transforming WAT-to-BAT (browning) is a promising strategy for the treatment of obesity, since it would lead to an increase in energy expenditure. Rosiglitazone (Rosi), an agonist of the peroxisome proliferator-activated receptor γ (PPARγ), is known to be a potent browning inducer in subcutaneous WAT. However, the effectiveness of Rosi has been quite limited because of several off-target effects. The objective of this study was to develop locally administered Rosi-loaded nanoparticles (Rs-NPs) with the ability to target adipocytes to achieve the adipose tissue-specific activation of PPARγ, thus causing the browning of WAT. We prepared dual targeted Rs-NPs that were modified with a specific peptide that targets prohibitin that are expressed in adipocytes, and a cell penetrating peptide for enhancing cellular uptake and controlling intracellular trafficking. The Rs-NPs modified with a single ligand were internalized into mature adipocytes and induced browning activity in vitro but they failed to significantly affect the body weight of the diet-induced obese mice model. The dual-targeted Rs-NPs induced a strong browning activity, both in vitro and in vivo, and successfully inhibited the progression of obesity, as evidenced by the shrinkage of hypertrophied adipocytes without any detectable systemic adverse effects. Meanwhile, free Rosi aggravated hepatic steatosis and did not cause adipose tissue browning nor the inhibition of body weight gain. We conclude that the increased energy expenditure via adipose tissue browning using dual-targeted Rs-NP is a promising strategy for the treatment of obesity and its related metabolic syndrome.

Nucleic Acid-Based Approaches for Tumor Therapy

Within the last decade, the introduction of checkpoint inhibitors proposed to boost the patients' anti-tumor immune response has proven the efficacy of immunotherapeutic approaches for tumor therapy. Furthermore, especially in the context of the development of biocompatible, cell type targeting nano-carriers, nucleic acid-based drugs aimed to initiate and to enhance anti-tumor responses have come of age. This review intends to provide a comprehensive overview of the current state of the therapeutic use of nucleic acids for cancer treatment on various levels, comprising (i) mRNA and DNA-based vaccines to be expressed by antigen presenting cells evoking sustained anti-tumor T cell responses, (ii) molecular adjuvants, (iii) strategies to inhibit/reprogram tumor-induced regulatory immune cells e.g., by RNA interference (RNAi), (iv) genetically tailored T cells and natural killer cells to directly recognize tumor antigens, and (v) killing of tumor cells, and reprograming of constituents of the tumor microenvironment by gene transfer and RNAi. Aside from further improvements of individual nucleic acid-based drugs, the major perspective for successful cancer therapy will be combination treatments employing conventional regimens as well as immunotherapeutics like checkpoint inhibitors and nucleic acid-based drugs, each acting on several levels to adequately counter-act tumor immune evasion.

Gene transfection of primary mouse hepatocytes in 384-well plates

We report the development of an improved in vitro transfection assay to test the efficiency of non-viral vector DNA nanoparticle transfection of primary hepatocytes. The protocol describes the isolation of viable hepatocytes from a mouse by collagenous perfusion. Primary mouse hepatocytes are plated in 384-well plates and cultured for 24 h prior to transfection with polyethylenimine (PEI) or peptide DNA nanoparticles. Luciferase expression is measured after 24 h following the addition of ONE-Glo substrate. The gene transfer assay for primary hepatocytes was optimized for cell plating number, DNA dose, and PEI to DNA ratio. The assay was applied to compare the expression mediated by mRNA relative to two plasmids possessing different promoters. The reported assay provides reliable in vitro expression results that allow direct comparison of the efficiency of different non-viral gene delivery vectors.

Tissue-Specific Delivery of Oligonucleotides

From the initial discovery of short-interfering RNA (siRNA) and antisense oligonucleotides for specific gene knockdown at the posttranscriptional level to the current CRISPR-Cas9 system offering gene editing at the genomic level, oligonucleotides, in addition to their biological functions in storing and conveying genetic information, provide the most prominent solutions to targeted gene therapies. Nonetheless, looking into the future of curing cancer and acute diseases, researchers are only cautiously optimistic as the cellular delivery of these polyanionic biomacromolecules is still the biggest hurdle for their therapeutic realization. To overcome the delivery obstacle, oligonucleotides have been encapsulated within or conjugated with delivery vehicles for enhanced membrane penetration, improved payload, and tissue-specific delivery. Such delivery systems include but not limited to virus-based vehicles, gold-nanoparticle vehicles, formulated liposomes, and synthetic polymers. In this chapter, delivery challenges imposed by biological barriers are briefly discussed; followed by recent advances in tissue-specific oligonucleotide delivery utilizing both viral and nonviral delivery vectors, discussing their advantages, and how judicious design and formulation could improve and expand their potential as delivery vehicles.

Dual-mechanism based CTLs infiltration enhancement initiated by Nano-sapper potentiates immunotherapy against immune-excluded tumors

The failure of immunotherapies in immune-excluded tumor (IET) is largely ascribed to the void of intratumoral cytotoxic T cells (CTLs). The major obstacles are the excessive stroma, defective vasculatures and the deficiency of signals recruiting CTLs. Here we report a dual-mechanism based CTLs infiltration enhancer, Nano-sapper, which can simultaneously reduce the physical obstacles in tumor microenvironment and recruiting CTLs to potentiate immunotherapy in IET. Nano-sapper consists a core that co-loaded with antifibrotic phosphates-modified α-mangostin and plasmid encoding immune-enhanced cytokine LIGHT. Through reversing the abnormal activated fibroblasts, decreasing collagen deposition, normalizing the intratumoral vasculatures, and in situ stimulating the lymphocyte-recruiting chemoattractants expression, Nano-sapper paves the road for the CTLs infiltration, induces the intratumoral tertiary lymphoid structures, thus reshapes tumor microenvironment and potentiates checkpoint inhibitor against IET. This study demonstrates that the combination of antifibrotic agent and immune-enhanced cytokine might represent a modality in promoting immunotherapy against IET.

The exclusion of cytotoxic T cells remains an important barrier to the efficacy of immunotherapies. Here the authors demonstrate that the combination anti-fibrosis agents and immune-enhanced cytokines can enhance T cell infiltration in a mouse model of pancreatic cancer.

Lipid-based nanoparticle technologies for liver targeting

Liver diseases such as hepatitis, cirrhosis, and hepatocellular carcinoma are global health problems accounting for approximately 800 million cases and over 2 million deaths per year worldwide. Major drawbacks of standard pharmacological therapies are the inability to deliver a sufficient concentration of a therapeutic agent to the diseased liver, and nonspecific drug delivery leading to undesirable systemic side effects. Additionally, depending on the specific liver disease, drug delivery to a subset of liver cells is required. In recent years, lipid nanoparticles have been developed to passively and actively target drugs to the liver. The success of this approach has been highlighted by the FDA-approval of the first liver-targeting lipid nanoparticle, ONPATTRO, in 2018 and many other promising candidate technologies are expected to follow. This review summarizes recent developments of various lipid-based liver-targeting technologies, namely solid-lipid nanoparticles, liposomes, niosomes and micelles, and discusses the challenges and future perspectives in this field.

Self-Illuminating Agents for Deep-Tissue Optical Imaging

Optical imaging plays an indispensable role in biology and medicine attributing to its noninvasiveness, high spatiotemporal resolution, and high sensitivity. However, as a conventional optical imaging modality, fluorescence imaging confronts issues of shallow imaging depth due to the need for real-time light excitation which produces tissue autofluorescence. By contrast, self-luminescence imaging eliminates the concurrent light excitation, permitting deeper imaging depth and higher signal-to-background ratio (SBR), which has attracted growing attention. Herein, this review summarizes the progress on the development of near-infrared (NIR) emitting self-luminescence agents in deep-tissue optical imaging with highlighting the design principles including molecular- and nano-engineering approaches. Finally, it discusses current challenges and guidelines to develop more effective self-illuminating agents for biomedical diagnosis and treatment.

Accumulation and cytotoxicity assessment of TAT-IONPs on cancerous mammalian cells

Nanotechnology is a fast-growing research technology. Nanoparticles have intensive scientific applications in many fields. Depending on the physical and chemical characteristics of a nanoparticle, it can be used either as a treatment agent to fight disease or as a delivery vehicle to transport the therapeutic drug to a specified biological organ, tissue, and cell. Cytotoxicity evaluation of nanoparticles is one of the primary concerns in clinical practices to avoid unpredicted or undesirable interactions that could worsen the case. Iron oxide nanoparticle (IONP) is the most utilized nanoparticle in medical fields for treatment, diagnostic, and imaging. This paper is designated to investigate the cytotoxicity of IONPs that decorated with Trans-Activator of Transcription (TAT) protein. WST-1 assay and flow cytometry were used to assess the cytotoxicity of TAT-IONPs, which showed no significant cytotoxic effect on mammalian breast cancer cells (MCF-7). Nanoparticles accumulation in the cell's cytoplasm was evaluated from TEM images by measuring the size of the endosome. The results indicate that TAT-IONPs can be used as a safe and non-toxic nanoplatform for targeted delivery at 50 µg/ml or less. Also, they present an approach by which the area of intracellular endosome can be assessed from the TEM images of fixed cells. In this study, the endosome size increased in a time-dependent manner.

Liposomal Nanostructures for Drug Delivery in Gastrointestinal Cancers

Gastrointestinal (GI) cancers like liver, pancreatic, colorectal, and gastric cancer remain some of the most difficult and aggressive cancers. Nanoparticles like liposomes had been approved in the clinic for cancer therapy dating as far back as 1995. Over the years, liposomal formulations have come a long way, facing several roadblocks and failures, and advancing by optimizing formulations and incorporating novel design approaches to navigate therapeutic delivery challenges. The first liposomal formulation for a GI cancer drug was approved recently in 2015, setting the stage for further clinical developments of liposome-based delivery systems for therapies against GI malignancies. This article reviews the design considerations and strategies that can be used to deliver drugs to GI tumors, the wide range of therapeutic agents that have been explored in preclinical as well as clinical studies, and the current therapies that are being investigated in the clinic against GI malignancies.

Calcium phosphate nanocarriers for drug delivery to tumors: imaging, therapy and theranostics

Calcium phosphate (CaP) was engineered as a drug delivery nanocarrier nearly 50 years ago due to its biocompatibility and biodegradability. In recent years, several approaches have been developed for the preparation of size-controllable, stable and multifunctional CaP nanocarriers, and several targeting moieties have also been decorated on the surface of these nanocarriers for active targeting. The CaP nanocarriers have been utilized for loading probes, nucleic acids, anticancer drugs and photosensitizers for cancer imaging, therapy and theranostics. Herein, we reviewed the recent advances in the preparation strategies of CaP nanocarriers and the applications of these nanocarriers in tumor diagnosis, gene delivery, drug delivery and theranostics and finally provided perspectives.

Triple-Targeting Delivery of CRISPR/Cas9 To Reduce the Risk of Cardiovascular Diseases

A high level of low-density lipoprotein cholesterol (LDL-C) in the blood is a major risk factor for coronary heart disease. Herein, we present a triple-targeting strategy to generate a loss-of-function mutation in Pcsk9, which regulates plasma cholesterol levels, using a nanocarrier-delivered CRISPR/Cas9 system. Nuclear localization signal (NLS)-tagged Cas9 and Pcsk9-targeted single guide RNA (sgPcsk9) were complexed with gold nanoclusters (GNCs) modified with cationic HIV-1-transactivating transcriptor (TAT) peptide and further encapsulated in a galactose-modified lipid layer to target the nanoclusters to the liver. The resulting nanoclusters had an in vitro Pcsk9-editing efficiency of about 60 % and resulting in a decrease in plasma LDL-C in mice of approximately 30%. No off-target mutagenesis was detected in 10 sites with high similarity. This approach may have therapeutic potential for the prevention and treatment of cardiovascular disease without side effects.

Biomolecule-assisted green synthesis of nanostructured calcium phosphates and their biomedical applications

Calcium phosphates (CaPs) are ubiquitous in nature and vertebrate bones and teeth, and have high biocompatibility and promising applications in various biomedical fields. Nanostructured calcium phosphates (NCaPs) are recognized as promising nanocarriers for drug/gene/protein delivery owing to their high specific surface area, pH-responsive degradability, high drug/gene/protein loading capacity and sustained release performance. In order to control the structure and surface properties of NCaPs, various biomolecules with high biocompatibility such as nucleic acids, proteins, peptides, liposomes and phosphorus-containing biomolecules are used in the synthesis of NCaPs. Moreover, biomolecules play important roles in the synthesis processes, resulting in the formation of various NCaPs with different sizes and morphologies. At room temperature, biomolecules can play the following roles: (1) acting as a biocompatible organic phase to form biomolecule/CaP hybrid nanostructured materials; (2) serving as a biotemplate for the biomimetic mineralization of NCaPs; (3) acting as a biocompatible modifier to coat the surface of NCaPs, preventing their aggregation and increasing their colloidal stability. Under heating conditions, biomolecules can (1) control the crystallization process of NCaPs by forming biomolecule/CaP nanocomposites before heating; (2) prevent the rapid and disordered growth of NCaPs by chelating with Ca2+ ions to form precursors; (3) provide the phosphorus source for the controlled synthesis of NCaPs by using phosphorus-containing biomolecules. This review focuses on the important roles of biomolecules in the synthesis of NCaPs, which are expected to guide the design and controlled synthesis of NCaPs. Moreover, we will also summarize the biomedical applications of NCaPs in nanomedicine and tissue engineering, and discuss their current research trends and future prospects.

Targeted Interleukin-22 Gene Delivery in the Liver by Polymetformin and Penetratin-Based Hybrid Nanoparticles to Treat Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is now a leading cause of chronic liver disease, and there is currently no available treatment strategy. Interleukin-22 (IL-22) has been recognized as a promising agent for alleviating NAFLD, but the efficacy of IL-22 is far from satisfactory because safe dose of IL-22 elicited limited improvement, whereas higher concentration might induce serious side effects and off-target toxicities. Thus, targeted and sustained expression of IL-22 in the liver is necessary. To meet the challenge, we elaborately developed a novel polymetformin carrier by conjugating biguanide to chitosan, termed chitosan-metformin (CM), which could exert advanced gene delivery efficiency and possess intrinsic therapeutic efficacy from metformin for NAFLD. CM accompanied with penetratin and DSPE-PEG2000 could self-assemble to form stable nanocomplexes with IL-22 gene via electrostatic interaction. This nanoparticle (CDPIA) exerted desirable particle size at ∼100 nm, fine morphology, and efficient cellular internalization. Furthermore, CDPIA also demonstrated a unique superiority in endosomal escape capacity and satisfactory biocompatibility as well as predominant liver accumulation. Most importantly, CDPIA distinctly alleviated hepatic steatosis, restored insulin sensitivity, and improved metabolic syndrome in high-fat-diet-fed mice model. This liver-targeted delivery of IL-22 activated STAT3/Erk1/2 and Nrf2/SOD1 signaling transductions as well as modulated lipid-metabolism-related gene expression. These findings altogether demonstrated that the polymetformin and penetratin-based hybrid nanoparticles could be exploited as a novel safe and efficient strategy for the improvement of NAFLD.

Porous Inorganic Carriers Based on Silica, Calcium Carbonate and Calcium Phosphate for Controlled/Modulated Drug Delivery: Fresh Outlook and Future Perspectives

Porous inorganic nanostructured materials are widely used nowadays as drug delivery carriers due to their adventurous features: suitable architecture, large surface area and stability in the biological fluids. Among the different types of inorganic porous materials, silica, calcium carbonate, and calcium phosphate have received significant attention in the last decade. The use of porous inorganic materials as drug carriers for cancer therapy, gene delivery etc. has the potential to improve the life expectancy of the patients affected by the disease. The main goal of this review is to provide general information on the current state of the art of synthesis of the inorganic porous particles based on silica, calcium carbonate and calcium phosphate. Special focus is dedicated to the loading capacity, controllable release of drugs under internal biological stimuli (e.g., pH, redox, enzymes) and external noninvasive stimuli (e.g., light, magnetic field, and ultrasound). Moreover, the diverse compounds to deliver with silica, calcium carbonate and calcium phosphate particles, ranging from the commercial drugs to genetic materials are also discussed.

Metabolically stabilized double-stranded mRNA polyplexes

The metabolic instability of mRNA currently limits its utility for gene therapy. Compared to plasmid DNA, mRNA is significantly more susceptible to digestion by RNase in the circulation following systemic dosing. To increase mRNA metabolic stability, we hybridized a complementary reverse mRNA with forward mRNA to generate double-stranded mRNA (dsmRNA). RNase A digestion of dsmRNA established a 3000-fold improved metabolic stability compared to single-stranded mRNA (ssmRNA). Formulation of a dsmRNA polyplex using a PEG-peptide further improved the stability by 3000-fold. Hydrodynamic dosing and quantitative bioluminescence imaging of luciferase expression in the liver of mice established the potent transfection efficiency of dsmRNA and dsmRNA polyplexes. However, hybridization of the reverse mRNA against the 5' and 3' UTR of forward mRNA resulted in UTR denaturation and a tenfold loss in expression. Repeat dosing of dsmRNA polyplexes produced an equivalent transient expression, suggesting the lack of an immune response in mice. Co-administration of excess uncapped dsmRNA with a dsmRNA polyplex failed to knock down expression, suggesting that dsmRNA is not a Dicer substrate. Maximal circulatory stability was achieved using a fully complementary dsmRNA polyplex. The results established dsmRNA as a novel metabolically stable and transfection-competent form of mRNA.

Tailoring Platinum(IV) Amphiphiles for Self-Targeting All-in-One Assemblies as Precise Multimodal Theranostic Nanomedicine

Drug, targeting ligand, and imaging agent are the three essential components in a nanoparticle-based drug delivery system. However, tremendous batch-to-batch variation of composition and drug content typically accompany the current approaches of building these components together. Herein, we report the design of photoactivatable platinum(IV) (Pt(IV)) amphiphiles containing one or two hydrophilic lactose targeting ligands per hydrophobic Pt(IV) prodrug for an all-in-one precise nanomedicine. Self-assembly of these Pt(IV) amphiphiles results in either micelle or vesicle formation with a fixed Pt/targeting moiety ratio and a constantly high content of Pt. The micelles and vesicles are capable of hepatoma cell-targeting, fluorescence/Pt-based CT imaging and have shown effective anticancer efficacy under laser irradiation in vitro and in vivo. This photoactivatable, active self-targeting, and multimodal theranostic amphiphile strategy shows great potential in constructing precise nanomedicine.

CCRK is a novel signalling hub exploitable in cancer immunotherapy

Cyclin-dependent kinase 20 (CDK20), or more commonly referred to as cell cycle-related kinase (CCRK), is the latest member of CDK family with strong linkage to human cancers. Accumulating studies have reported the consistent overexpression of CCRK in cancers arising from brain, colon, liver, lung and ovary. Such aberrant up-regulation of CCRK is clinically significant as it correlates with tumor staging, shorter patient survival and poor prognosis. Intriguingly, the signalling molecules perturbed by CCRK are divergent and cancer-specific, including the cell cycle regulators CDK2, cyclin D1, cyclin E and RB in glioblastoma, ovarian carcinoma and colorectal cancer, and KEAP1-NRF2 cytoprotective pathway in lung cancer. In hepatocellular carcinoma (HCC), CCRK mediates virus-host interaction to promote hepatitis B virus-associated tumorigenesis. Further mechanistic analyses reveal that CCRK orchestrates a self-reinforcing circuitry comprising of AR, GSK3β, β-catenin, AKT, EZH2, and NF-κB signalling for transcriptional and epigenetic regulation of oncogenes and tumor suppressor genes. Notably, EZH2 and NF-κB in this circuit have been recently shown to induce IL-6 production to facilitate tumor immune evasion. Concordantly, in a hepatoma preclinical model, ablation of Ccrk disrupts the immunosuppressive tumor microenvironment and enhances the therapeutic efficacy of immune checkpoint blockade via potentiation of anti-tumor T cell responses. In this review, we summarized the multifaceted tumor-intrinsic and -extrinsic functions of CCRK, which represents a novel signalling hub exploitable in cancer immunotherapy.

Galactose Derivative-Modified Nanoparticles for Efficient siRNA Delivery to Hepatocellular Carcinoma

Successful siRNA therapy requires suitable delivery systems with targeting moieties such as small molecules, peptides, antibodies, or aptamers. Galactose (Gal) residues recognized by the asialoglycoprotein receptor (ASGPR) can serve as potent targeting moieties for hepatocellular carcinoma (HCC) cells. However, efficient targeting to HCC via galactose moieties rather than normal liver tissues in HCC patients remains a challenge. To achieve more efficient siRNA delivery in HCC, we synthesized various galactoside derivatives and investigated the siRNA delivery capability of nanoparticles modified with those galactoside derivatives. In this study, we assembled lipid/calcium/phosphate nanoparticles (LCP NPs) conjugated with eight types of galactoside derivatives and demonstrated that phenyl β-d-galactoside-decorated LCP NPs (L4-LCP NPs) exhibited a superior siRNA delivery into HCC cells compared to normal hepatocytes. VEGF siRNAs delivered by L4-LCP NPs downregulated VEGF expression in HCC in vitro and in vivo and led to a potent antiangiogenic effect in the tumor microenvironment of a murine orthotopic HCC model. The efficient delivery of VEGF siRNA by L4-LCP NPs that resulted in significant tumor regression indicates that phenyl galactoside could be a promising HCC-targeting ligand for therapeutic siRNA delivery to treat liver cancer.

Charge reversible calcium phosphate lipid hybrid nanoparticle for siRNA delivery

Bcl-2 gene is an important target to treat lung cancer. The small interference RNA (siRNA) of Bcl-2 gene (siBcl-2) can specifically silence Bcl-2 gene. However, naked siBcl-2 is difficult to accumulate in the tumor tissue to exert its activity. In this paper, a calcium phosphate lipid hybrid nanoparticle that possessed charge reversible property was prepared to enhance the activity of siBcl-2 in vivo. The average diameter and zeta potential of siBcl-2 loaded calcium phosphate lipid hybrid nanoparticles (LNPS@siBcl-2) were 80 nm and −13 mV at pH7.4 whereas the diameter and zeta potential changed to 1506 nm and +9 mV at pH5.0. LNPS@siBcl-2 could efficiently deliver siBcl-2 to the cytoplasm and significantly decreased the expression of Bcl-2 in A549 cells. Moreover, the in vivo experimental results showed that most of the Cy5-siBcl-2 accumulated in tumor tissue after LNPS@Cy5-siBcl-2 was administered to tumor-bearing mice by tail vein injection. Meanwhile, the expression of Bcl-2 was decreased but the expression of the BAX and Caspase-3 was increased in tumor tissue. LNPS@siBcl-2 significantly inhibited the growth of tumor in tumor-bearing mice without any obvious systemic toxicity. Thus, the charge reversible calcium phosphate lipid hybrid nanoparticle was an excellent siBcl-2 delivery carrier to improve the activity of siBcl-2 in vivo. LNPS@siBcl-2 has potential in the treatment of lung cancer.

Calcium phosphate-based nanosystems for advanced targeted nanomedicine

Synthetic calcium phosphates (CaPs) are the most widely accepted bioceramics for the repair and reconstruction of bone tissue defects. The recent advancements in materials science have prompted a rapid progress in the preparation of CaPs with nanometric dimensions, tailored surface characteristics, and colloidal stability opening new perspectives in their use for applications not strictly related to bone. In particular, the employment of CaPs nanoparticles as carriers of therapeutic and imaging agents has recently raised great interest in nanomedicine. CaPs nanoparticles, as well as other kinds of nanoparticles, can be engineered to specifically target the site of the disease (cells or organs), thus minimizing their dispersion in the body and undesired organism-nanoparticles interactions. The most promising and efficient approach to improve their specificity is the 'active targeting', where nanoparticles are conjugated with a targeting moiety able to recognize and bind with high efficacy and selectivity to receptors that are highly expressed only in the therapeutic site. The aim of this review is to give an overview on advanced targeted nanomedicine with a focus on the most recent reports on CaP nanoparticles-based systems, specifically designed for the active targeting. The distinctive characteristics of CaP nanoparticles with respect to the other kinds of nanomaterials used in nanomedicine are also discussed.

Synergism between a cell penetrating peptide and a pH-sensitive cationic lipid in efficient gene delivery based on double-coated nanoparticles

We report on the development of a highly efficient gene delivery system based on synergism between octaarginine (R8), a representative cell penetrating peptide, and YSK05, a recently developed pH-sensitive cationic lipid. Attaching a high density of R8 on the surface of YSK05 nanoparticles (NPs) that contained encapsulated plasmid DNA resulted in the formation of positively charged NPs with improved transfection efficiency. To avoid the development of a net positive charge, we controlled the density and topology of the R8 peptide through the use of a two-step coating methodology, in which the inner lipid coat was modified with a low density of R8 which was then covered with an outer neutral YSK05 lipid layer. Although used in low amounts, the R8 peptide improved cellular uptake and endosomal escape of the DNA encapsulated in YSK05 NPs, which resulted in a high transfection efficiency. The two-step coating design was essential for achieving a high degree of transfection, as evidenced by the low activity of NPs modified with the same amount of R8 in a regular single-coated design. In addition, a high transfection efficiency was not observed when R8 or YSK05 were used alone, which confirms the existence of a synergistic effect between both components. The results of this study indicate that cationic cell penetrating peptides have the ability to improve transfection activities without imparting a net positive charge when used in the proper amount and in conjunction with the appropriate design. This is expected to significantly increase the potential applications of these peptides as tools for augmenting the activity of lipid nanoparticles used in gene delivery.

Microfluidic platforms for modeling biological barriers in the circulatory system

Microfluidic platforms have recently become popular as in vitro models because of their superiority in recapitulating microenvironments compared with conventional in vitro models. By providing various biochemical and biomechanical cues, healthy and diseased models at the organ level can be applied to disease progression and treatment studies. Microfluidic technologies are especially suitable for modeling biological barriers because the flow in the microchannels mimics the blood flow and body fluids at the interfaces of crucial organs, such as lung, intestine, liver, kidney, brain, and skin. These barriers have similar structures and can be studied with similar approaches for the testing of pharmaceutical compounds. Here, we review recent developments in microfluidic platforms for modeling biological barriers in the circulatory system.

Calcium-based biomaterials for diagnosis, treatment, and theranostics

Calcium-based (CaXs) biomaterials including calcium phosphates, calcium carbonates, calcium silicate and calcium fluoride have been widely utilized in the biomedical field owing to their excellent biocompatibility and biodegradability. In recent years, CaXs biomaterials have been strategically integrated with imaging contrast agents and therapeutic agents for various molecular imaging modalities including fluorescence imaging, magnetic resonance imaging, ultrasound imaging or multimodal imaging, as well as for various therapeutic approaches including chemotherapy, gene therapy, hyperthermia therapy, photodynamic therapy, radiation therapy, or combination therapy, even imaging-guided therapy. Compared with other inorganic biomaterials such as silica-, carbon-, and gold-based biomaterials, CaXs biomaterials can dissolve into nontoxic ions and participate in the normal metabolism of organisms. Thus, they offer safer clinical solutions for disease theranostics. This review focuses on the state-of-the-art progress in CaXs biomaterials, which covers from their categories, characteristics and preparation methods to their bioapplications including diagnosis, treatment, and theranostics. Moreover, the current trends and key problems as well as the future prospects and challenges of CaXs biomaterials are also discussed at the end.