Multifunctional Envelope-Type siRNA Delivery Nanoparticle Platform for Prostate Cancer Therapy

Stimuli-Responsive Polymer-Prodrug Hybrid Nanoplatform for Multistage siRNA Delivery and Combination Cancer Therapy

Nanoparticles (NPs) formulated with cationic lipids and/or polymers have shown substantial potential for systemic delivery of RNA therapeutics such as small interfering RNA (siRNA) for the treatment of cancer and other diseases. While both cationic lipids and polymers have demonstrated the promise to facilitate siRNA encapsulation and endosomal escape, they could also hamper cytosolic siRNA release due to charge interaction and induce potential toxicities. Herein, a unique polymer-prodrug hybrid NP platform was developed for multistage siRNA delivery and combination cancer therapy. This NP system is composed of (i) a hydrophilic polyethylene glycol (PEG) shell, (ii) a hydrophobic NP core made with a tumor microenvironment (TME) pH-responsive polymer, and (iii) charge-mediated complexes of siRNA and amphiphilic cationic mitoxantrone (MTO)-based prodrug that are encapsulated in the NP core. After intravenous administration, the long-circulating NPs accumulate in tumor tissues and then rapidly release the siRNA-prodrug complexes via TME pH-mediated NP disassociation for subsequent tissue penetration and cytosolic transport. With the overexpressed esterase in tumor cells to hydrolyze the amphiphilic structure of the prodrug and thereby induce destabilization of the siRNA-prodrug complexes, the therapeutic siRNA and anticancer drug MTO can be efficiently released in the cytoplasm, ultimately leading to the combinational inhibition of tumor growth via concurrent RNAi-mediated gene silencing and MTO-mediated chemotherapy.

Selective Cell Penetrating Peptide-Functionalized Envelope-Type Chimeric Lipopepsomes Boost Systemic RNAi Therapy for Lung Tumors

Small interfering RNA (siRNA) is considered a highly specific and potent biotherapeutic that holds tremendous potential for the treatment of various diseases. The clinical translation of siRNA is, however, greatly impeded by the lack of safe and efficient delivery vehicles in vivo. Here, the development of selective cell penetrating peptide (CPP33)-functionalized chimeric lipopepsomes (CPP33-CLP) for efficient encapsulation and selective delivery of polo-like kinase 1 specific siRNA (siPLK1) to orthotopic A549 human lung tumor in vivo is reported. Interestingly, siRNA is tightly encapsulated into CPP33-CLP with a superb encapsulation efficiency of over 95% owing to the thick strong electrostatic interactions. Notably, siPLK1-loaded CPP33-CLP (siPLK1-CPP33-CLP) is selectively internalized by A549 human lung cancer cells, efficiently escapes from endosomes, and swiftly releases siRNA into the cytoplasm, affording a significant sequence-specific gene silencing in vitro. Moreover, siPLK1-CPP33-CLP exhibits prolonged blood circulation, enhanced tumor accumulation, effective suppression of tumor growth, and considerably elevated survival time of orthotopic A549 human lung tumor-bearing nude mice. These chimeric lipopepsomes appear as an attractive and potent nanoplatform for safe and targeted siRNA delivery.

RNA-silencing nanoprobes for effective activation and dynamic imaging of neural stem cell differentiation

To achieve the clinical potential of neural stem cells (NSCs), it is crucial to activate NSC differentiation into neurons and simultaneously monitor the process of NSC differentiation. However, there are many challenges associated with regulating and tracking NSC differentiation.

Methods: We developed a redox-responsive multifunctional nanocomplex with a disulfide bond—cvNC—for the delivery of siRNAs to induce NSC differentiation through sequence-specific RNA interference (RNAi) and real-time imaging of sequential mRNA expression during differentiation. The stability and specificity of cvNCs were studied in vitro. Controlled release of siRNA, gene silencing efficiency, as well as real-time imaging of cvNCs on Tubb3 and Fox3 mRNAs during NSC differentiation were evaluated.

Results: The introduction of a redox-sensitive disulfide bond not only ensures the remarkable performance of cvNC, such as high stability, controlled siRNA release, and enhanced gene silencing efficiency, but also effectively stimulates NSC differentiation into neurons. More importantly, the cvNC can track NSC differentiation in real-time by monitoring the sequential expression of mRNAs.

Conclusion: Our study indicates that cvNC can serve as a robust system for exploring NSCs differentiation process as well as other biological events in living cells.

Nanobuffering of pH-Responsive Polymers: A Known but Sometimes Overlooked Phenomenon and Its Biological Applications

With recent advances in polymer chemistry, materials science, and nanotechnology, pH-responsive polymers have a significant impact in a number of diverse fields. Fundamental studies of these polymers are thus highly desirable as they may lead to new insights into the rational design of pH-responsive polymers with specific effects. In this Perspective, we focus on the nanobuffering of pH-responsive polymers (NBPRP). Although researchers have known of such buffering effects for more than a century, for example, in the context of the Henderson-Hasselbalch equation, modern synthesis and analysis routes now enable us to analyze these effects on the nanometer scale. In this way, the NBPRP phenomenon was explicitly defined and described by Gauthier and colleagues in the February issue of ACS Nano. Here, we highlight several potential areas in which the NBPRP could enable innovative classes of biological applications. We expect deeper mechanistic understanding of nanobuffering effects induced by pH-responsive polymers to have a significant impact on the future development and applications of these polymers.

Quick synthesis of a novel combinatorial delivery system of siRNA and doxorubicin for a synergistic anticancer effect

Purpose: Combining siRNA and other chemotherapeutic agents into one nanocarrier can overcome the multidrug resistance (MDR) phenomenon by synergistically MDR relative genes silencing and elevated chemotherapeutic activity. Most of these systems are typically fabricated through complicated procedures, which involves materials preparation, drug loading and modifications. Herein, the purpose of this study is to develop a new and fast co-delivery system of siRNA and doxorubicin for potentially synergistic cancer treatment.

Methods: The co-delivery system is constructed conveniently by a stable complex consisting of doxorubicin bound to siRNA via intercalation firstly, followed by interacting with (3-Aminopropyl)triethoxysilane (APTES) electrostatically and Tetraethyl orthosilicate (TEOS) co-condensed, and the characterizations of the resultant nanocarrier are also investigated. Furthermore, this study evaluates the synergistic anti-cancer efficacy in MCF-7/MDR cells after treatment of siRNA and doxorubicin ‘two in one’ nanocarriers.

Results: We establish a new and fast method to craft a co-delivery system of siRNA and doxorubicin with controllable and nearly uniform size, and the entire fabrication process only costs in about 10 minutes. The resultant co-delivery system presents high loading capacities of siRNA and doxorubicin, and the encapsulated doxorubicin plays a pH-responsive control release. Further, biological functionality tests of the synthesized co-delivery nanocarriers show high inhibition of P-gp protein encoded by MDR-1 gene in MCF-7/MDR cells (a variant of human breast cancer cell line with drug resistance) after transfection of these nanocarriers carrying MDR-1 siRNA and doxorubicin simultaneously, which sensitize the MCF-7/MDR cells to doxorubicin, overall leading to improved cell suppression.

Conclusion: Collectively, this co-delivery system not only serves as potent therapeutics for synergistic cancer therapy, it also may facilitate the bench-to-bedside translation of combinatorial delivery system as a robust drug nanocarrier by allowing for fabricating a simply and fast nanocarrier for co-delivery of siRNA and doxorubicin with predictable high production rate.

Nanoparticle Therapy for Prostate Cancer: Overview and Perspectives

Traditional prostate cancer therapy and especially chemotherapy has faced many challenges. Low accumulation levels, rapid clearance or drug resistance at the tumor site have been central to why the effect of chemotherapy drugs has declined. Applications of nanotechnology to biomedicine have enabled the development of nanoparticle therapeutic carriers suited for the delivery of chemotherapeutics in cancer therapy. This review describes the current nature of nanoparticle therapeutic carriers for prostate cancer. It describes typical nanocarriers commonly used for the delivery of chemotherapy or for imaging examination. Targeting strategies and related influencing factors are investigated to find ways of enhancing treatment effects of nanoparticles. The overall purpose of this review is to further understanding and to offer recommendations on the design and development of therapeutic nanoparticles for prostate cancer.

AIE Featured Inorganic-Organic Core@Shell Nanoparticles for High-Efficiency siRNA Delivery and Real-Time Monitoring

RNA interference (RNAi) is demonstrated as one of the most powerful technologies for sequence-specific suppression of genes in disease therapeutics. Exploration of novel vehicles for small interfering RNA (siRNA) delivery with high efficiency, low cytotoxicity, and self-monitoring functionality is persistently pursued. Herein, by taking advantage of aggregation-induced emission luminogen (AIEgen), we developed a novel class of Ag@AIE core@shell nanocarriers with regulable and uniform morphology. It presented excellent efficiencies in siRNA delivery, target gene knockdown, and cancer cell inhibition in vitro. What's more, an anticancer efficacy up to 75% was achieved in small animal experiments without obvious toxicity. Attributing to the unique AIE properties, real-time intracellular tracking of siRNA delivery and long-term tumor tissue imaging were successfully realized. Compared to the commercial transfection reagents, significant improvements were obtained in biocompatibility, delivery efficiency, and reproducibility, representing a promising future of this nanocarrier in RNAi-related cancer therapeutics.

Self-Assembling RNA Nanoparticle for Gene Expression Regulation in a Model System

In the search for enzymatically processed RNA fragments, we found the novel three-way junction motif. The structure prediction suggested the arrangement of helices at acute angle approx. 60°. This allows the design of a trimeric RNA nanoparticle that can be functionalized with multiple regulatory fragments. Such RNA nano-object of equilateral triangular shape was applied for gene expression regulation studies in two independent cellular systems. Biochemical and functional studies confirmed the predicted shape and structure of the nanoparticle. The regulatory siRNA fragments incorporated into the nanoparticle were effectively released and triggered gene silencing. The regulatory effect was prolonged when induced with structuralized RNA compared to unstructured siRNAs. In these studies, the enzymatic processing of the motif was utilized for function release from the nanoparticle, enabling simultaneous delivery of different regulatory functions. This methodology of sequence search, RNA structural prediction, and application for rational design opens a new way for creating enzymatically processed RNA nanoparticles.

Multifunctional Nanobiohybrid Material Composed of Ag@Bi2Se3/RNA Three-Way Junction/miRNA/Retinoic Acid for Neuroblastoma Differentiation

Nanoparticle-based cell differentiation therapy has attracted increasing research interest as it is a promising substitute for conventional cancer treatment methods. Here, the topological insulator bismuth selenide nanoparticle (Bi₂Se₃ NP) was core-shelled with silver (Ag@Bi₂Se₃) to represent remarkable biocompatibility and plasmonic features (ca. 2.3 times higher than those of Ag nanoparticle). Moreover, a newly developed RNA three-way junction (3WJ) structure was designed for the quad-functionalization of any type of nanoparticle and surface. One leg of the 3WJ was attached to the Ag@Bi₂Se₃, and the other leg harbored a cell-penetrating RNA and a florescence tag. The third leg was designed to inhibit micro-RNA-17 (miR-17) and to further release retinoic acid (RA). A new drug delivery mechanism was developed for the slow release of RA inside the cytosol based on the prerequisite inhibition of miR-17 using a strand displacement strategy. In this paper, we report a simple methodology for resolving the hydrophobicity challenges of RA by its conjugation with a RNA strand (RA/R) through a stimulus-responsive cross-linker. The developed nanobiohybrid material could fully differentiate SH-SY5Y cancer cells into neurons and stop their growth in 6 days without requiring sequential treatments which has not been reported yet. Using a surface-enhanced Raman spectroscopy technique, the RA delivery and the cell differentiation process were monitored nondestructively in real time. The fabricated nanobiohybrid material could open the new horizons in the fabrication of different diagnostic/therapeutic agents.

Prospective treatment of Parkinson's disease by a siRNA-LDH nanoconjugate

In the world, among the neurodegenerative diseases, Parkinson's is the second most common disease. Although several medications are available in the market, this disease still remains incurable and only the symptoms are controlled to a certain extent with severe side effects. For these reasons we decided to search for a novel therapeutic measure. The objective of this publication was to find a therapeutic procedure to cure this devastating disease. In this study, a biocompatible, easily permeable, cationic nanoparticle-layered double hydroxide was synthesized. Within the layers of these nanoparticles we intercalated α synuclein siRNA, which helps to silence the α synuclein gene. After the intercalation, which was optimized at a 1 : 40 ratio of siRNA : (LDH), we studied its stability in blood by a RNase protection test and serum protection assay. Both proved that LDH was an excellent nanocarrier that can protect intercalated molecules within its layers. After that, several cellular studies were performed by FACS to evaluate its biocompatibility after intercalation and cellular internalization. Results of the biocompatibility studies found it to be nontoxic and in the cellular internalization study, 51.55% of cells were taken into the nanoconjugate and confocal microscopy supported the data from FACS. Lastly, ELISA was performed to discover protein levels in the control, overexpressed, and treated groups of the SH-SY5Y cell line. These results verified that this nanoconjugate is a protective treatment procedure for Parkinson's disease.

Synthesis, characterization, and formulation of poly-puerarin as a biodegradable and biosafe drug delivery platform for anti-cancer therapy

Poly-puerarin, a novel biodegradable biomaterial as a drug delivery platform in anti-tumour therapy.

A “self-accelerating endosomal escape” siRNA delivery nanosystem for significantly suppressing hyperplasia via blocking the ERK2 pathway

Highly efficient ERK2 silencing in VSMCs via a “self-accelerating endosomal escape” siRNA transport nanosystem.

Engineering mannosylated nanogels with membrane-disrupting properties

In this work, mannosylated core-cross-linked nanogels are designed that contain cationic moieties in their core.

Structural exploration of hydrophobic core in polycationic micelles for improving siRNA delivery efficiency and cell viability

Improving siRNA delivery efficiency often encounters a dilemma with poor or decreased biocompatibility for polycationic micelles.

Cancer nanomedicine: focus on recent developments and self-assembled peptide nanocarriers

The applications of nanoparticulate drug delivery have received abundant interest in the field of cancer diagnosis and treatment.

Recent Development of pH-Responsive Polymers for Cancer Nanomedicine

Cancer remains a leading cause of death worldwide with more than 10 million new cases every year. Tumor-targeted nanomedicines have shown substantial improvements of the therapeutic index of anticancer agents, addressing the deficiencies of conventional chemotherapy, and have had a tremendous growth over past several decades. Due to the pathophysiological characteristics that almost all tumor tissues have lower pH in comparison to normal healthy tissues, among various tumor-targeted nanomaterials, pH-responsive polymeric materials have been one of the most prevalent approaches for cancer diagnosis and treatment. In this review, we summarized the types of pH-responsive polymers, describing their chemical structures and pH-response mechanisms; we illustrated the structure-property relationships of pH-responsive polymers and introduced the approaches to regulating their pH-responsive behaviors; we also highlighted the most representative applications of pH-responsive polymers in cancer imaging and therapy. This review article aims to provide general guidelines for the rational design of more effective pH-responsive nanomaterials for cancer diagnosis and treatment.

A strategy using mesoporous polymer nanospheres as nanocarriers of Bcl-2 siRNA towards breast cancer therapy

Small interference RNA (siRNA) has demonstrated unprecedented potential as a therapy for drug-resistant cancer. However, efficient cellular delivery is still a challenge due to hydrolytic sensitivity and poor cellular uptake of siRNA. Strategies to conjugate siRNA to the delivery vehicle and activate innate immunity have shown low in vivo efficacy. Therefore, nanomedicine approaches have become the main focus in this field. B-cell lymphoma 2 (Bcl-2) is the founding member of the Bcl-2 family of regulatory proteins that regulate cell death (apoptosis), by either inducing (pro-apoptotic) or inhibiting (anti-apoptotic) apoptosis. In this report, a nanomedicine system is constructed using Bcl-2 siRNA as the therapeutic agent and mesoporous polymer nanosphere (MPN) carriers to both improve cellular internalization and achieve Bcl-2 silencing and cell apoptosis. MPNs were prepared through a two-stage hydrothermal process at two different temperatures, which was deliberately designed to form nanospheres via self-assembly and create mesoporous structures by removing the pore-forming templates. Such MPNs were proved to be biodegradable. Without any carbonization process, MPNs still keep many active groups which endow them with excellent properties for functionalization purposes. Finally, the FA-targeted-Bcl-2-siRNA-loaded nanoparticles were constructed by a layer-by-layer assembly by electrostatic interactions after nitrification. These nanoparticles were efficiently delivered into breast cancer (BC) cells, showing a significant sequence-specific inhibition of Bcl-2 mRNA expression in BC cells, enhanced tumor cell apoptosis and tumor therapeutic efficacy. Taken together, this study establishes a novel therapeutic system for cancer therapy.

A Robust Nanoparticle Platform for RNA Interference in Macrophages to Suppress Tumor Cell Migration

Macrophages are one of the most abundant immune cells in the solid tumor and their increased density is associated with the specific pathological features of cancers, including invasiveness, metastasis, immunosuppression, neovascularization, and poor response to therapy. Therefore, reprogramming macrophage behavior is emerging as a promising therapeutic modality for cancer treatment. RNA interference (RNAi) technology is one of the powerful strategies for the regulation of macrophage activities by silencing specific genes. However, as polyanionic biomacromolecules, RNAi therapeutics such as small interfering RNA (siRNA) cannot readily cross cell membrane and thus specific delivery vehicles are required to facilitate the cytosolic siRNA delivery. Herein, we developed a robust nanoparticle (NP) platform for efficient siRNA delivery and gene silencing in macrophages. This NP platform is composed of biodegradable poly (ethylene glycol)-b-poly (𝜀-caprolactone) (PEG-b-PCL), poly (𝜀-caprolactone)-b-poly (2-aminoethyl ethylene phosphate) (PCL-b-PPEEA), and PCL homopolymer. We chose CC-chemokine ligand 18 (CCL-18) as a proof of concept therapeutic target and our results demonstrate that the CCL-18 silencing in macrophages can significantly inhibit the migration of breast cancer cells. The successful regulation of the macrophage behavior demonstrated herein shows great potential as an effective strategy for cancer therapy.

In vivo hepatocellular expression of interleukin-22 using penetratin-based hybrid nanoparticles as potential anti-hepatitis therapeutics

Hepatocellular injury is the pathological hallmark of hepatitis and a crucial driver for the progression of liver diseases, while the treatment options are commonly restricted. Interleukin-22 (IL-22) has attracted special attention as a potent survival factor for hepatocytes that both prevents and repairs the injury of hepatocytes through activation of STAT3 signaling pathway. We hypothesized that the ability to generate potent expression of IL-22 locally for the treatment of severe hepatocellular injury in hepatitis was a promising strategy to enhance efficacy and overcome off-target effects. Accordingly, we developed a polypeptide penetratin-based hybrid nanoparticle system (PDPIA) carrying IL-22 gene by a self-assembly process. This nanocomplex modified with penetratin featured direct translocation across the cellular or endosomal membrane but mild zeta-potential to facilitate the high cellular internalization and endosomal escape of the gene cargos as well as scarcely Kupffer cells uptake. More importantly, PDPIA afforded preferential liver accumulation and predominant hepatocytes internalization following systemic administration, which showed pharmacologically suitable organ and sub-organ-selective properties. Subsequent studies confirmed a considerable protective role of PDPIA in a model of severe hepatitis induced by concanavalin A, evidenced by reduced hepatocellular injury and evaded immune response. The locally expressed IL-22 by PDPIA activated STAT3/Erk signal transduction, and thus promoted hepatocyte regeneration, inhibited reactive oxygen species (ROS) accumulation as well as prevented the dysfunction of mitochondrial. In addition, this system did not manifest side effects or systemic toxicity in mice. Collectively, the high versatility of PDPIA rendered its promising applications might be an effective agent to treat various hepatic disorders.

Self-Assembled Metal-Phenolic Nanoparticles for Enhanced Synergistic Combination Therapy against Colon Cancer

Engineering functional nanomaterials to have both high therapeutic efficacy and minimal side-effects has become a promising strategy for next-generation cancer treatments. Herein, an adenosine triphosphate (ATP) depletion and reactive oxygen species-enhanced combination chemotherapy platform is introduced whereby therapeutic samarium (Sm³⁺ ) ions and (-)-epicatechin (EC) are integrated via a metal-phenolic network (Sm^III -EC). The independent pathway between Sm³⁺ and EC can achieve a synergistic therapeutic effect through the mitochondrial dysfunction process. Sm^III -EC nanoparticles cause a significant reduction of viability of C26 murine colon carcinoma cells while with lower systemic toxic effects on normal cell lines. Sm^III -EC nanoparticles are used to directly compare with a clinic anticancer drug 5-fluorouracil. Sm^III -EC nanoparticles not only decrease the tumor volume but also do not affect the body weight of mice and normal organs, showing significant advantages over clinic counterpart. These facts suggest that Sm^III -EC nanoparticles represent a clinically promising candidate for colon cancer treatment with a targeted therapeutic effect and minimum side toxicity.

Nanoparticles targeting extra domain B of fibronectin-specific to the atherosclerotic lesion types III, IV, and V-enhance plaque detection and cargo delivery

Extra domain B of fibronectin (FN-EDB) is upregulated in the extracellular matrix during tissue remodeling and has been postulated as a potential biomarker for atherosclerosis, yet no systematic test for FN-EDB in plaques has been reported. We hypothesized that FN-EDB expression would intensify in advanced plaques. Furthermore, engineering of FN-EDB-targeted nanoparticles (NPs) could enable imaging/diagnosis and local delivery of payloads to plaques.

Methods: The amount of FN-EDB in human atherosclerotic and normal arteries (ages: 40 to 85 years) was assessed by histological staining and quantification using an FN-EDB-specific aptide (APT_FN-EDB). FN-EDB-specific NPs that could serve as MRI beacons were constructed by immobilizing APT_FN-EDB on the NP surface containing DTPA[Gd]. MRI visualized APT_FN-EDB-[Gd]NPs administered to atherosclerotic apolipoprotein E-deficient mice in the brachiocephalic arteries. Analysis of the ascending-to-descending thoracic aortas and the aortic roots of the mice permitted quantitation of Gd, FN-EDB, and APT_FN-EDB-[Gd]NPs. Cyanine, a model small molecule drug, was used to study the biodistribution and pharmacokinetics of APT_FN-EDB-NPs to evaluate their utility for drug delivery.

Results: Atherosclerotic tissues had significantly greater FN-EDB-positive areas than normal arteries (P < 0.001). This signal pertained particularly to Type III (P < 0.01), IV (P < 0.01), and V lesions (P < 0.001) rather than Type I and II lesions (AHA classification). FN-EDB expression was positively correlated with macrophage accumulation and neoangiogenesis. Quantitative analysis of T1-weighted images of atherosclerotic mice revealed substantial APT_FN-EDB-[Gd]NPs accumulation in plaques compared to control NPs, conventional MRI contrast agent (Gd-DTPA) or accumulation in wild-type C57BL/6J mice. Additionally, the APT_FN-EDB-NPs significantly prolonged the blood-circulation time (t_1/2: ~ 6 h) of a model drug and increased its accumulation in plaques (6.9-fold higher accumulation vs. free drug).

Conclusions: Our findings demonstrate augmented FN-EDB expression in Type III, IV, and V atheromata and that APT_FN-EDB-NPs could serve as a platform for identifying and/or delivering agents locally to a subset of atherosclerotic plaques.

pH-triggered charge-reversal and redox-sensitive drug-release polymer micelles codeliver doxorubicin and triptolide for prostate tumor therapy

AIM

To significantly promote cancer cell uptake and to achieve combination therapy and on-demand drug release, a pH-triggered charge-switchable and redox-responsive drug-release nanovehicle was developed in this study.

MATERIALS AND METHODS

The nanocarrier was constructed by conjugating 3,3'-dithiodipropionic acid-modified doxorubicin (DTPA-DOX) and 2,3-dimethylmaleic anhydride (DMA) to the side amino groups of poly(ethylene glycol)-b-poly(L-lysine) (PEG-b-PLL) and by encapsulating triptolide (TRI) into the hydrophobic core. The surface charge of the obtained nanocarriers (DA-ss-DT) can change from negative to positive in response to tumor extracellular acidity pH, and the nanocarriers capably release two drugs in response to intracellular high glutathione (GSH) environment.

RESULTS

Compared to the control group, the in vitro cellular uptake of DA-ss-DT by human prostate cancer PC-3 cells was significantly promoted in slightly acidic conditions, and the drug could be rapidly released in the high concentration of GSH conditions. The in vitro and in vivo antitumor experiments exhibited that the DA-ss-DT nanoparticles have a great antitumor effect in comparison to the control group.

CONCLUSION

These findings demonstrated that the DA-ss-DT nanoparticles supply a useful strategy for promoting cellular uptake and synergetic anticancer therapy.

Functional Nanoparticles for Tumor Penetration of Therapeutics

Theranostic nanoparticles recently received great interest for uniting unique functions to amplify therapeutic efficacy and reduce side effects. Despite the enhanced permeability and retention (EPR) effect, which amplifies the accumulation of nanoparticles at the site of a tumor, tumor heterogeneity caused by the dense extracellular matrix of growing cancer cells and the interstitial fluid pressure from abnormal angiogenesis in the tumor inhibit drug/particle penetration, leading to inhomogeneous and limited treatments. Therefore, nanoparticles for penetrated delivery should be designed with different strategies to enhance efficacy. Many strategies were developed to overcome the obstacles in cancer therapy, and they can be divided into three main parts: size changeability, ligand functionalization, and modulation of the tumor microenvironment. This review summarizes the results of ameliorated tumor penetration approaches and amplified therapeutic efficacy in nanomedicines. As the references reveal, further study needs to be conducted with comprehensive strategies with broad applicability and potential translational development.

Tumor-Associated Fibronectin Targeted Liposomal Nanoplatform for Cyclophilin A siRNA Delivery and Targeted Malignant Glioblastoma Therapy

Malignant glioblastoma (GBM) is the most aggressive brain cancer that has a very low survival rate. With the rapid development of nanotechnology in the past few decades, the use of nanoparticles (NPs) for nucleic acid delivery is expected to have a revolutionary impact on GBM therapy. However, clinical success in GBM therapy remains a formidable challenge, mainly due to suboptimal in vivo delivery of therapeutics to glioma cells. Herein, we developed an aptamer-like peptide (aptide)-decorated liposomal nanoplatform for systemic small interfering RNA (siRNA) delivery and targeted GBM therapy. This nanoplatform is mainly composed of the following key components: (i) classic liposome structure with an aqueous core that can encapsulate therapeutic siRNA; (ii) hydrophilic polyethylene glycol (PEG) chains on the outer shell to prolong blood circulation; and (iii) surface-encoded aptide to specifically target the extra-domain B (EDB) of fibronectin that over-expressed on glioma cells. After systemic administration of these new siRNA delivery NPs, they can target the glioma cells and efficiently inhibit the GBM tumor growth by silencing the expression of cyclophilin A (CypA), which is up-regulated in brain cancer and plays an important role in malignant transformation of brain cancer and maintaining glioma cell stemness. These results suggest that the reported RNA interference (RNAi) NP platform herein could become an effective tool for targeted GBM therapy.

Mitochondria-targeted zirconium metal-organic frameworks for enhancing the efficacy of microwave thermal therapy against tumors

Although microwave (MW) thermal therapy has been widely studied for the treatment of tumors due to its less invasiveness, recurrence of tumors is still observed because of the relatively low bioavailability of MW sensitizers. For enhancing the bioavailability of MW sensitizers, triphenyl phosphate (TPP)-conjugated and doxorubicin (DOX)-loaded porous zirconium metal-organic framework nanocubes (ZrMOF NCs) modified with polyethylene glycol (PEG), ZrMOF-PEG-TPP@DOX NCs, were prepared as a MW sensitizer with mitochondrial-targeting ability. Moreover, the mitochondria are more susceptible to heat than the tumor tissues; this leads to improved tumor cell apoptosis. The results of this study indicate that ZrMOF NCs exhibit excellent heating effects due to the increased collisions of ions in the micropores of ZrMOFs under MW irradiation. In addition, ZrMOF-PEG-TPP@DOX NCs show preferential aggregation in the mitochondria, confirmed by confocal microscopy images. In vivo MW thermal therapeutic efficacy of ZrMOF-PEG-TPP@DOX NCs + MW is also better without recurrence during treatment than that of ZrMOF-PEG@DOX NCs + MW at a similar thermal therapeutic temperature; this reveals that the mitochondrial-targeting strategy can enhance the MW thermal therapeutic efficacy. This study provides a new biosafe MW sensitizer with mitochondrial-targeting ability for enhancing the efficacy of MW thermal therapy against tumors.

Redox-Responsive Nanoparticle-Mediated Systemic RNAi for Effective Cancer Therapy

Biodegradable polymeric nanoparticles (NPs) have demonstrated significant potential to improve the systemic delivery of RNA interference (RNAi) therapeutics, such as small interfering RNA (siRNA), for cancer therapy. However, the slow and inefficient siRNA release inside tumor cells generally observed for most biodegradable polymeric NPs may result in compromised gene silencing efficacy. Herein, a biodegradable and redox-responsive NP platform, composed of a solid poly(disulfide amide) (PDSA)/cationic lipid core and a lipid-poly(ethylene glycol) (lipid-PEG) shell for systemic siRNA delivery to tumor cells, is developed. This newly generated NP platform can efficiently encapsulate siRNA under extracellular environments and can respond to the highly concentrated glutathione (GSH) in the cytoplasm to induce fast intracellular siRNA release. By screening a library of PDSA polymers with different structures and chain lengths, the optimized NP platform shows the unique features of i) long blood circulation, ii) high tumor accumulation, iii) fast GSH-triggered intracellular siRNA release, and iv) exceptionally effective gene silencing. Together with the facile polymer synthesis technique and robust NP formulation enabling scale-up, this new redox-responsive NP platform may become an effective tool for RNAi-based cancer therapy.

Biomedical applications of mRNA nanomedicine

As an attractive alternative to plasmid DNA, messenger RNA (mRNA) has recently emerged as a promising class of nucleic acid therapeutics for biomedical applications. Advances in addressing the inherent shortcomings of mRNA and in the development of nanoparticle-based delivery systems have prompted the development and clinical translation of mRNA-based medicines. In this review, we discuss the chemical modification strategies of mRNA to improve its stability, minimize immune responses, and enhance translational efficacy. We also highlight recent progress in nanoparticle-based mRNA delivery. Considerable attention is given to the increasingly widespread applications of mRNA nanomedicine in the biomedical fields of vaccination, protein-replacement therapy, gene editing, and cellular reprogramming and engineering.

Charge and Assembly Reversible Micelles Fueled by Intracellular ATP for Improved siRNA Transfection

Hydrophobic modification on polycations were commonly used to improve the stability and transfection efficiency of polyplexes. However, the improved stability often means undesired release of the encapsulated siRNA, limiting the application of cationic micelles for siRNA delivery. The current strategy of preparing bioresponsive micelles based on the cleavage of sensitive linkages between polycation and hydrophobic part was far from sufficient, owing to the siRNA binding of the separated polycations from micelles leading to the incomplete release of siRNA. In this study, we propose a new strategy by the combination of micelles disassembly and separated polycations charge reversal. FPBA (3-fluoro-4-carboxyphenylboronic acid) grafted PEI 1.8 k (polyethylenimine) as the polycations of PEI-FPBA and dopamine (with diol-containing moiety) conjugated with cholesterol as the hydrophobic part (Chol-Dopa). The PFCDM micelles was assembled by PEI-FPBA and Chol-Dopa, based on the FPBA-Dopa conjugation. The prepared PFCDM showed strong siRNA loading ability and superior stability in the presence of PBS or serum. Besides, the PFCDM exhibited excellent ATP sensibility. The intracellular ATP could effectively trigger the disassembly of micelles and charge reversal of PEI-FPBA, resulting in the burst release of siRNA in the cytosol. With the property of extracellular stability and intracellular instability, PFCDM displayed good performance on in vitro and in vivo luciferase silencing on 4T1 cells. It should also be noted that the assembly of low molecular weight PEI was relatively safe to cells compared with 25 k PEI. To sum up, the ATP-fueled assembly and charge reversible micelles gave examples for polyplexes to achieve better stability and on demand cargo release at the same time and shows potential to be used for in vitro and in vivo siRNA transfection.

Bifunctional Au@Bi2 Se3 Core-Shell Nanoparticle for Synergetic Therapy by SERS-Traceable AntagomiR Delivery and Photothermal Treatment

For the first time, topological insulator bismuth selenide nanoparticles (Bi₂ Se₃ NP) are core-shelled with gold (Au@Bi₂ Se₃ ) i) to represent considerably small-sized (11 nm) plasmonic nanoparticles, enabling accurate bioimaging in the near-infrared region; ii) to substantially improve Bi₂ Se₃ biocompatibility, iii) water dispersibility, and iv) surface functionalization capability through straightforward gold-thiol interaction. The Au@Bi₂ Se₃ is subsequently functionalized for v) effective targeting of SH-SY5Y cancer cells, vi) disrupting the endosome/lysosome membrane, vii) traceable delivery of antagomiR-152 and further synergetic oncomiR knockdown and photothermal therapy (PTT). Unprecedentedly, it is observed that the Au shell thickness has a significant impact on evoking the exotic plasmonic features of Bi₂ Se₃ . The Au@Bi₂ Se₃ possesses a high photothermal conversion efficiency (35.5%) and a remarkable surface plasmonic effect (both properties are approximately twofold higher than those of 50 nm Au nanoparticles). In contrast to the siRNA/miRNA delivery methods, the antagomiR delivery is based on strand displacement, in which the antagomiR-152 is displaced by oncomiR-152 followed by a surface-enhanced Raman spectroscopy signal drop. This enables both cancer cell diagnosis and in vitro real-time monitoring of the antagomiR release. This selective PTT nanoparticle can also efficiently target solid tumors and undergo in vivo PTT, indicating its potential clinical applications.

Targeted siRNA delivery using aptamer-siRNA chimeras and aptamer-conjugated nanoparticles

The sequence-specific gene-silencing ability of small interfering RNA (siRNA) has been exploited as a new therapeutic approach for the treatment of a variety of diseases. However, efficient and safe delivery of siRNA into target cells is still a challenge in the clinical development of siRNA-based therapeutics. Recently, nucleic acid-based aptamers that target cell surface proteins have emerged as a new class of targeting moieties due to their high specificity and avidity. To date, various aptamer-mediated siRNA delivery systems have been developed to enhance the RNA interference (RNAi) efficacy of siRNA via targeted delivery. In this review, we summarize recent advances in developing aptamer-mediated siRNA delivery systems for RNAi therapeutics, mainly aptamer-siRNA chimeras and aptamer-functionalized nanocarriers incorporating siRNA, with a focus on their molecular designs and formulations. In addition, the challenges and engineering strategies of aptamer-mediated siRNA delivery systems for clinical translation are discussed. This article is categorized under: Biology-Inspired Nanomaterials > Nucleic Acid-Based Structures Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Self-assembly of peptide amphiphiles for drug delivery: the role of peptide primary and secondary structures

Peptide amphiphiles (PAs), functionalized with alkyl chains, are capable of self-assembling into various nanostructures. Recently, PAs have been considered as ideal drug carriers due to their good biocompatibility, specific biological functions, and hypotoxicity to normal cells and tissues. Meanwhile, the nanocarriers formed by PAs are able to achieve controlled drug release and enhanced cell uptake in response to the stimulus of the physiological environment or specific biological factors in the location of the lesion. However, the underlying detailed drug delivery mechanism, especially from the aspect of primary and secondary structures of PAs, has not been systematically summarized or discussed. Focusing on the relationship between the primary and secondary structures of PAs and stimuli-responsive drug delivery applications, this review highlights the recent advances, challenges, and opportunities of PA-based functional drug nanocarriers, and their potential pharmaceutical applications are discussed.

Improved Cell Transfection of siRNA by pH-Responsive Nanomicelles Self-Assembled with mPEG- b-PHis- b-PEI Copolymers

Here, the novel pH-responsive nanomicelles self-assembled with amphipathic meo-poly(ethylene glycol)- b-poly(l-histidine)- b-polyethylenimine (mPEG- b-PHis- b-PEI, EHE) copolymers based on hydrophobic interaction of PHis with deprotonation of imidazoles were developed for siRNA transfection. The cationic nanomicelles could electrostatically compact siRNA into stable EHE/siRNA nanoplexes with a hydrodynamic diameter of ∼190 nm and present a low toxicity in normal physiological condition (pH ∼ 7.4). Different from pH-irresponsive ECE/siRNA nanoplexes based on mPEG- b-poly(ε-caprolactone)- b-PEI (ECE), the EHE/siRNA nanoplexes exhibited a higher cellular uptake along with an increased ζ-potential (from +18 to +32 mV) when the pH changed from 7.4 to 6.8 (extracellular acidic microenvironments). After cell internalization, the EHE/siRNA nanoplexes also exhibited an enhanced nanostructural disassembling and release of siRNA from lysosomal acidic microenvironments (pH ∼ 5.5). Furthermore, it was demonstrated that the EHE/siEGFR nanoplexes downregulated the expression levels of the corresponding mRNA and protein more efficiently than ECE/siEGFR in HeLa cells. The improved siRNA silencing effects of EHE/siEGFR nanoplexes resulted from the higher cellular uptake and enhanced endosomal/lysosomal escape, which is associated with the pH-responsive disassembly of nanostructure as well as the synergistic "proton sponge" effects of PHis and PEI in EHE copolymers. Therefore, the pH-responsive EHE nanomicelles would be promising and potential carriers for cell transfection of siRNA.

Using porous magnetic iron oxide nanomaterials as a facile photoporation nanoplatform for macromolecular delivery

The intracellular delivery of exogenous macromolecules such as functional proteins, antibodies, polysaccharides and nucleic acids into living cells for biomedical applications is of great interest. Even though great efforts have been devoted to this task, universal delivery systems that provide excellent intracellular delivery performance combined with easy cell recovery are urgently needed. Magnetic iron oxide nanoparticles show promising potential for various biomedical applications because of their advantages such as high biocompatibility and cost-effectiveness. Herein, a new facile platform for macromolecular delivery was developed based on the photothermal properties of porous magnetic iron oxide nanoparticles (P-MNPs). The near-infrared radiation (NIR) absorption behavior of P-MNPs remarkably facilitates the delivery of macromolecules into cells while maintaining high cell viability. Furthermore, the assistance of polycationic polyethylenimine improves the efficiency of DNA delivery. Most importantly, the cells could be easily recovered after macromolecular delivery by trypsinization, which is of great significance for further practical application of the delivery system. The facile and cost-effective platform proposed in this work provides a new avenue for the utilization of P-MNPs in macromolecular delivery.

Human Albumin Fragments Nanoparticles as PTX Carrier for Improved Anti-cancer Efficacy

For enhanced anti-cancer performance, human serum albumin fragments (HSAFs) nanoparticles (NPs) were developed as paclitaxel (PTX) carrier in this paper. Human albumins were broken into fragments via degradation and crosslinked by genipin to form HSAF NPs for better biocompatibility, improved PTX drug loading and sustained drug release. Compared with crosslinked human serum albumin NPs, the HSAF-NPs showed relative smaller particle size, higher drug loading, and improved sustained release. Cellular and animal results both indicated that the PTX encapsulated HSAF-NPs have shown good anti-cancer performance. And the anticancer results confirmed that NPs with fast cellular internalization showed better tumor inhibition. These findings will not only provide a safe and robust drug delivery NP platform for cancer therapy, but also offer fundamental information for the optimal design of albumin based NPs.

Poly (amidoamine) (PAMAM) dendrimer mediated delivery of drug and pDNA/siRNA for cancer therapy

Poly (amidoamine) (PAMAM) dendrimers are well-defined, highly branched macromolecules with numerous active amine groups on the surface. Because of their unique properties, PAMAM dendrimers have steadily grown in popularity in drug delivery, gene therapy, medical imaging and diagnostic application. This review focuses on the recent developments on the application in PAMAM dendrimers as effective carriers for drug and gene (pDNA, siRNA) delivery in cancer therapy, including: a) PAMAM for anticancer drug delivery; b) PAMAM and gene therapy; c) PAMAM used in overcoming tumor multidrug resistance; d) PAMAM used for hybrid nanoparticles; and e) PAMAM linked or loaded in other nanoparticles.

Photo-tearable tape close-wrapped upconversion nanocapsules for near-infrared modulated efficient siRNA delivery and therapy

RNA interference (RNAi) has become an appealing therapeutic approach for cancer and other diseases. One key challenge is the effective protection of these small fragile biomolecules against complicated physiological environments as well as efficient on-demand release. Here we design a photo-tearable polymer tape close-wrapped nanocapsule for efficient NIR modulated siRNA delivery. The photo-tearable nanocapsules comprise core-shell upconversion nanoparticles (UCNPs) coated with mesoporous silica layer for loading of photosensitizer hypocrellin A (HA) and small interfering RNA (siRNA) against polo-like kinase 1 (PLK1), and covalently bound thin membranes of polyethylene glycol (PEG) via a synthesized photocleavable linker (PhL). Upon irradiation at 980 nm, the UCNPs produce UV emissions to break PhL and tear out PEG membrane for siRNA release, and blue emissions to activate HA for generating reactive oxygen species (ROS). The close PEG membrane wrapping not only guarantees the efficient intracellular photocleavage, but also extends the circulation time and protects the loaded cargos from leakage and degradation. The ROS assists endosomal escape of the loaded cargos, therefore effectively improves the gene silencing efficiency and the suppressions of cell proliferation in vitro and tumor growth in vivo. The proposed photo-tearable tape-wrapped nanocapsules have promising potential application in precision medicine.

Computational approaches in design of nucleic acid-based therapeutics

Recent advances in computational and experimental methods have led to novel avenues for therapeutic development. Utilization of nucleic acids as therapeutic agents and/or targets has been recently gaining attention due to their potential as high-affinity, selective molecular building blocks for various therapies. Notably, development of computational algorithms for predicting accessible RNA binding sites, identifying therapeutic target sequences, modeling delivery into tissues, and designing binding aptamers have enhanced therapeutic potential for this new drug category. Here, we review trends in drug development within the pharmaceutical industry and ways by which nucleic acid-based drugs have arisen as effective therapeutic candidates. In particular, we focus on computational and experimental approaches to nucleic acid-based drug design, commenting on challenges and outlooks for future applications.

Polydopamine-Functionalized CA-(PCL-ran-PLA) Nanoparticles for Target Delivery of Docetaxel and Chemo-photothermal Therapy of Breast Cancer

Current limitations of cancer therapy include the lack of effective strategy for target delivery of chemotherapeutic drugs, and the difficulty of achieving significant efficacy by single treatment. Herein, we reported a synergistic chemo-photothermal strategy based on aptamer (Apt)-polydopamine (pD) functionalized CA-(PCL-ran-PLA) nanoparticles (NPs) for effective delivery of docetaxel (DTX) and enhanced therapeutic effect. The developed DTX-loaded Apt-pD-CA-(PCL-ran-PLA) NPs achieved promising advantages, such as (i) improved drug loading content (LC) and encapsulation efficiency (EE) initiated by star-shaped copolymer CA-(PCL-ran-PLA); (ii) effective target delivery of drugs to tumor sites by incorporating AS1411 aptamers; (iii) significant therapeutic efficacy caused by synergistic chemo-photothermal treatment. In addition, the pD coating strategy with simple procedures could address the contradiction between targeting modification and maintaining formerly excellent bio-properties. Therefore, with excellent bio-properties and simple preparation procedures, the DTX-loaded Apt-pD-CA-(PCL-ran-PLA) NPs effectively increased the local drug concentration in tumor sites, minimized side effects, and significantly eliminated tumors, indicating the promising application of these NPs for cancer therapy.

Inhibitor-GCPII Interaction: Selective and Robust System for Targeting Cancer Cells with Structurally Diverse Nanoparticles

Glutamate carboxypeptidase II (GCPII) is a membrane protease overexpressed by prostate cancer cells and detected in the neovasculature of most solid tumors. Targeting GCPII with inhibitor-bearing nanoparticles can enable recognition, imaging, and delivery of treatments to cancer cells. Compared to methods based on antibodies and other large biomolecules, inhibitor-mediated targeting benefits from the low molecular weight of the inhibitor molecules, which are typically stable, easy-to-handle, and able to bind the enzyme with very high affinity. Although GCPII is established as a molecular target, comparing previously reported results is difficult due to the different methodological approaches used. In this work, we investigate the robustness and limitations of GCPII targeting with a diverse range of inhibitor-bearing nanoparticles (various structures, sizes, bionanointerfaces, conjugation chemistry, and surface densities of attached inhibitors). Polymer-coated nanodiamonds, virus-like particles based on bacteriophage Qβ and mouse polyomavirus, and polymeric poly(HPMA) nanoparticles with inhibitors attached by different means were synthesized and characterized. We evaluated their ability to bind GCPII and interact with cancer cells using surface plasmon resonance, inhibition assay, flow cytometry, and confocal microscopy. Regardless of the diversity of the investigated nanosystems, they all strongly interact with GCPII (most with low picomolar K_i values) and effectively target GCPII-expressing cells. The robustness of this approach was limited only by the quality of the nanoparticle bionanointerface, which must be properly designed by adding a sufficient density of hydrophilic protective polymers. We conclude that the targeting of cancer cells overexpressing GCPII is a viable approach transferable to a broad diversity of nanosystems.

Dual-responsive polyplexes with enhanced disassembly and endosomal escape for efficient delivery of siRNA

Despite the extracellular barriers for siRNA delivery have been overcome by utilizing advanced nanoparticle delivery systems, the key intracellular barriers after internalization including efficient disassembly of siRNA and endosomal escape still remains challenging. To address the issues, we developed a unique pH- and redox potential-responsive polyplex delivery system based on the copolymer of mPEG-b-PLA-PHis-ssPEI1.8 k, which is composed of a pH-responsive copolymer of PEG-b-PLA-PHis (Mw 5 k) and a branched PEI (Mw1.8 k) linked with redox cleavable disulfide bond. The copolymer showed excellent siRNA complexation and protection abilities against endogenous substances at the relatively low N/P ratio of 6. The siRNA release from the polyplexes (N/P 6) was markedly increased from 13.62% to 58.67% under conditions simulating the endosomal microenvironment. Fluorescence resonance energy transfer (FRET) test also indicated a higher disassembly extent of siRNA from the copolymer. The accelerated siRNA release from the polyplexes was markedly restrained when the N/P ratio was raised above 10 due to the increasing of electrostatic interactions. The efficient endosomal escape of siRNA after internalization was confirmed by confocal microscopy, which was attributed to the cleavaged PEI chains inducing membrane destabilization, the "proton sponge effect" of PHis and PEI as well as the relative small size of after disassembly. The enhanced disassembly and endosomal escape were elucidated as the leading cause for polyplexes (N/P 6) showed more efficient Bcl-2 silencing (85.45%) than those polyplexes with higher N/P ratios (N/P 10 and 15). In vivo results further demonstrated that polyplexes (N/P 6) delivery of siBcl-2 significantly inhibited the MCF-7 breast tumor growth as compared to its counterparts. The incorporation of convertible non-electrical interactions at a balance with electrostatic interactions in complexation siRNA has been demonstrated as an effective strategy to achieve efficient disassembly from stable polyplexes. Moreover, polyplexes equipped with the enhanced disassembly and endosomal escape provides a new potential way to tackle the intracellular delivery bottleneck for siRNA delivery.

Polymer-Based Nanocarriers for Co-Delivery and Combination of Diverse Therapies against Cancers

Cancer gives rise to an enormous number of deaths worldwide nowadays. Therefore, it is in urgent need to develop new therapies, among which combined therapies including photothermal therapy (PTT) and chemotherapy (CHT) using polymer-based nanocarriers have attracted enormous interest due to the significantly enhanced efficacy and great progress has been made so far. The preparation of such nanocarriers is a comprehensive task involving the cooperation of nanomaterial science and biomedicine science. In this review, we try to introduce and analyze the structure, preparation and synergistic therapeutic effect of various polymer-based nanocarriers composed of anti-tumor drugs, nano-sized photothermal materials and other possible parts. Our effort may bring benefit to future exploration and potential applications of similar nanocarriers.

Nucleolin-Targeting AS1411-Aptamer-Modified Graft Polymeric Micelle with Dual pH/Redox Sensitivity Designed To Enhance Tumor Therapy through the Codelivery of Doxorubicin/TLR4 siRNA and Suppression of Invasion

In this article, a novel graft polymeric micelle with targeting function ground on aptamer AS1411 was synthesized. The micelle was based on chitosan-ss-polyethylenimine-urocanic acid (CPU) with dual pH/redox sensitivity and targeting effects. This micelle was produced for codelivering Toll-like receptor 4 siRNA (TLR4-siRNA) and doxorubicin (Dox). In vitro investigation revealed the sustained gene and drug release from Dox-siRNA-loaded micelles under physiological conditions, and this codelivery nanosystem exhibited high dual pH/redox sensitivity, rapid intracellular drug release, and improved cytotoxicity against A549 cells in vitro. Furthermore, the micelles loaded with TLR4-siRNA inhibited the migration and invasion of A549. Excellent tumor penetrating efficacy was also noted in the A549 tumor spheroids and solid tumor slices. In vivo, multiple results demonstrated the excellent tumor-targeting ability of AS1411-chitosan-ss-polyethylenimine-urocanic acid (ACPU) micelle in tumor tissues. The micelles exhibited excellent antitumor efficacy and low toxicity in the systemic circulation in lung-tumor-bearing BALB/c mice. These results conclusively demonstrated the great potential of the new graft copolymer micelle with targeting function for the targeted and efficient codelivery of chemotherapeutic drugs and genes in cancer treatment.

Fabrication of PEGylated Fe@Bi2S3 nanocomposites for dual-mode imaging and synergistic thermoradiotherapy

Multifunctional magnetic nanocomposites are fabricated for synergistic thermoradiotherapy and simultaneously MRI/CT dual-mode imaging.