Non-Covalently Functionalized of Single-Walled Carbon Nanotubes by DSPE-PEG-PEI for SiRNA Delivery

Multifunctional Mesoporous Silica-Coated Gold Nanorods Mediate Mild Photothermal Heating-Enhanced Gene/Immunotherapy for Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related deaths in the world. It is urgent to search for safe and effective therapies to address the CRC crisis. The siRNA-based RNA interference targeted silencing of PD-L1 has extensive potential in CRC treatment but is limited by the lack of efficient delivery vectors. In this work, the novel cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODNs)/siPD-L1 co-delivery vectors AuNRs@MS/CpG ODN@PEG-bPEI (ASCP) were successfully prepared by two-step surface modification of CpG ODNs-loading and polyethylene glycol-branched polyethyleneimine-coating around mesoporous silica-coated gold nanorods. ASCP promoted dendritic cells (DCs) maturation by delivering CpG ODNs, exhibiting excellent biosafety. Next, mild photothermal therapy (MPTT) mediated by ASCP killed tumor cells and released tumor-associated antigens, further promoting DC maturation. Furthermore, ASCP exhibited mild photothermal heating-enhanced performance as gene vectors, resulting in an increased PD-L1 gene silencing effect. Enhanced DCs maturity and enhanced PD-L1 gene silencing significantly promoted the anti-tumor immune response. Finally, the combination of MPTT and mild photothermal heating-enhanced gene/immunotherapy effectively killed MC38 cells, leading to strong inhibition of CRC. Overall, this work provided new insights into the design of mild photothermal/gene/immune synergies for tumor therapy and may contribute to translational nanomedicine for CRC treatment.

Novel Pharmaceutical Strategies for Enhancing Skin Penetration of Biomacromolecules

Skin delivery of biomacromolecules holds great advantages in the systemic and local treatment of multiple diseases. However, the densely packed stratum corneum and the tight junctions between keratinocytes stand as formidable skin barriers against the penetration of most drug molecules. The large molecular weight, high hydrophilicity, and lability nature of biomacromolecules pose further challenges to their skin penetration. Recently, novel penetration enhancers, nano vesicles, and microneedles have emerged as efficient strategies to deliver biomacromolecules deep into the skin to exert their therapeutic action. This paper reviews the potential application and mechanisms of novel skin delivery strategies with emphasis on the pharmaceutical formulations.

Effects of carbon nanotube-mediated Caspase3 gene silencing on cardiomyocyte apoptosis and cardiac function during early acute myocardial infarction

RNA interference (RNAi) technology can achieve efficient and specific silencing of Caspase3 gene expression, thus providing new options for anti-apoptosis treatment. However, delivering siRNA to specific cells and tissues in the body is a significant challenge. Therefore, we aim to construct a functionalized single-walled carbon nanotube (F-CNT) bound to siRNA from Caspase3. The obtained gene transfer carrier F-CNT-siCas3 not only demonstrated a good water solubility and biocompatibility, but also had a high transfection efficiency of up to 82%, which significantly downregulated the expression level of the Caspase3 gene miRNA and protein in primary cardiomyocytes. Furthermore, it was verified by in vivo experiments that Caspase3 gene silencing had obvious protective effects on myocardial cell apoptosis, ventricular remodeling, and cardiac function in Sprague-Dawley (SD) rats after coronary artery ligation. This study may provide an important theoretical basis for the application of F-CNT in vivo siRNA gene therapy to treat cardiovascular diseases.

Therapeutic efficacy of nanoparticles and routes of administration

In modern-day medicine, nanotechnology and nanoparticles are some of the indispensable tools in disease monitoring and therapy. The term “nanomaterials” describes materials with nanoscale dimensions (< 100 nm) and are broadly classified into natural and synthetic nanomaterials. However, “engineered” nanomaterials have received significant attention due to their versatility. Although enormous strides have been made in research and development in the field of nanotechnology, it is often confusing for beginners to make an informed choice regarding the nanocarrier system and its potential applications. Hence, in this review, we have endeavored to briefly explain the most commonly used nanomaterials, their core properties and how surface functionalization would facilitate competent delivery of drugs or therapeutic molecules. Similarly, the suitability of carbon-based nanomaterials like CNT and QD has been discussed for targeted drug delivery and siRNA therapy. One of the biggest challenges in the formulation of drug delivery systems is fulfilling targeted/specific drug delivery, controlling drug release and preventing opsonization. Thus, a different mechanism of drug targeting, the role of suitable drug-laden nanocarrier fabrication and methods to augment drug solubility and bioavailability are discussed. Additionally, different routes of nanocarrier administration are discussed to provide greater understanding of the biological and other barriers and their impact on drug transport. The overall aim of this article is to facilitate straightforward perception of nanocarrier design, routes of various nanoparticle administration and the challenges associated with each drug delivery method.

Multi-Drug/Gene NASH Therapy Delivery and Selective Hyperspectral NIR Imaging Using Chirality-Sorted Single-Walled Carbon Nanotubes

Single-walled carbon nanotubes (SWCNTs) can serve as drug delivery/biological imaging agents, as they exhibit intrinsic fluorescence in the near-infrared, allowing for deeper tissue imaging while providing therapeutic transport. In this work, CoMoCAT (Cobalt Molybdenum Catalyst) SWCNTs, chirality-sorted by aqueous two-phase extraction, are utilized for the first time to deliver a drug/gene combination therapy and image each therapeutic component separately via chirality-specific SWCNT fluorescence. Each of (7,5) and (7,6) sorted SWCNTs were non-covalently loaded with their specific payload: the PI3 kinase inhibitor targeting liver fibrosis or CCR5 siRNA targeting inflammatory pathways with the goal of addressing these processes in nonalcoholic steatohepatitis (NASH), ultimately to prevent its progression to hepatocellular carcinoma. PX-866-(7,5) SWCNTs and siRNA-(7,6) SWCNTs were each imaged via characteristic SWCNT emission at 1024/1120 nm in HepG2 and HeLa cells by hyperspectral fluorescence microscopy. Wavelength-resolved imaging verified the intracellular transport of each SWCNT chirality and drug release. The therapeutic efficacy of each formulation was further demonstrated by the dose-dependent cytotoxicity of SWCNT-bound PX-866 and >90% knockdown of CCR5 expression with SWCNT/siRNA transfection. This study verifies the feasibility of utilizing chirality-sorted SWCNTs for the delivery and component-specific imaging of combination therapies, also suggesting a novel nanotherapeutic approach for addressing the progressions of NASH to hepatocellular carcinoma.

Epigenetics in cancer therapy and nanomedicine

The emergence of nanotechnology applied to medicine has revolutionized the treatment of human cancer. As in the case of classic drugs for the treatment of cancer, epigenetic drugs have evolved in terms of their specificity and efficiency, especially because of the possibility of using more effective transport and delivery systems. The use of nanoparticles (NPs) in oncology management offers promising advantages in terms of the efficacy of cancer treatments, but it is still unclear how these NPs may be affecting the epigenome such that safe routine use is ensured. In this work, we summarize the importance of the epigenetic alterations identified in human cancer, which have led to the appearance of biomarkers or epigenetic drugs in precision medicine, and we describe the transport and release systems of the epigenetic drugs that have been developed to date.

Carbon nanotubes (CNTs) based advanced dermal therapeutics: current trends and future potential

The search for effective and non-invasive delivery modules to transport therapeutic molecules across skin has led to the discovery of a number of nanocarriers (viz.: liposomes, ethosomes, dendrimers, etc.) in the last few decades. However, available literature suggests that these delivery modules face several issues including poor stability, low encapsulation efficiency, and scale-up hurdles. Recently, carbon nanotubes (CNTs) emerged as a versatile tool to deliver therapeutics across skin. Superior stability, high loading capacity, well-developed synthesis protocol as well as ease of scale-up are some of the reason for growing interest in CNTs. CNTs have a unique physical architecture and a large surface area with unique surface chemistry that can be tailored for vivid biomedical applications. CNTs have been thus largely engaged in the development of transdermal systems such as tuneable hydrogels, programmable nonporous membranes, electroresponsive skin modalities, protein channel mimetic platforms, reverse iontophoresis, microneedles, and dermal buckypapers. In addition, CNTs were also employed in the development of RNA interference (RNAi) based therapeutics for correcting defective dermal genes. This review expounds the state-of-art synthesis methodologies, skin penetration mechanism, drug liberation profile, loading potential, characterization techniques, and transdermal applications along with a summary on patent/regulatory status and future scope of CNT based skin therapeutics.

Combinatorial therapeutic approaches with RNAi and anticancer drugs using nanodrug delivery systems

RNA interference (RNAi) is emerging as a powerful approach in cancer treatment. siRNA is an important RNAi tool that can be designed to specifically silence the expression of genes involved in drug resistance and chemotherapeutic inactivity. Combining siRNA and other therapeutic agents can overcome the multidrug resistance (MDR) phenomenon by simultaneously silencing genes and enhancing chemotherapeutic activity. Moreover, the therapeutic efficiency of anticancer drugs can be significantly improved by additive or synergistic effects induced by siRNA and combined therapies. Co-delivery of these diverse anticancer agents, however, requires specially designed nanocarriers. This review highlights the recent trends in siRNA/anticancer drug co-delivery systems under the major categories of liposomes/lipid, polymeric and inorganic nanoplatforms. The objective is to discuss the strategies for nanocarrier-based co-delivery systems using siRNA/anticancer drug combinations, emphasizing various siRNA targets that help overcome MDR and enhance therapeutic efficiency.

Synergistic Enhancement of Antitumor Efficacy by PEGylated Multi-walled Carbon Nanotubes Modified with Cell-Penetrating Peptide TAT

In the present study, a cell-penetrating peptide, the transactivating transcriptional factor (TAT) domain from HIV, was linked to PEGylated multi-walled carbon nanotubes (MWCNTs) to develop a highly effective antitumor drug delivery system. FITC was conjugated on MWCNTs-polyethylene glycol (PEG) and MWCNTs-PEG-TAT to provide fluorescence signal for tracing the cellular uptake of the nanocarrier. After loaded with an anticancer agent, doxorubicin (DOX) via π - π stacking interaction, the physicochemical characteristics, release profile and biological evaluation of the obtained nano-sized drug carrier were investigated. The DOX loaded MWCNTs-PEG and MWCNTs-PEG-TAT drug carriers both displayed appropriate particle size, excellent stability, high drug loading, and pH-dependent drug release profile. Nevertheless, compared with DOX-MWCNTs-PEG, DOX-MWCNTs-PEG-TAT showed improved cell internalization, intracellular distribution and potentiated anticancer efficacy due to the TAT-mediated membrane translocation, endosomal escape and nuclear targeting. Furthermore, the therapeutic efficacy of DOX was not compromised after being conjugated with MWCNTs-PEG-TAT and the proposed nanocarrier was also confirmed to have a good biocompatibility. In conclusion, our results suggested that the unique combination of TAT and MWCNTs as a multifunctional drug delivery system might be a powerful tool for improved anticancer drug development.