Inhibiting the cGAS-STING Pathway in Ulcerative Colitis with Programmable Micelles

Ulcerative colitis is a chronic condition in which a dysregulated immune response contributes to the acute intestinal inflammation of the colon. Current clinical therapies often exhibit limited efficacy and undesirable side effects. Here, programmable nanomicelles were designed for colitis treatment and loaded with RU.521, an inhibitor of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. STING-inhibiting micelles (SIMs) comprise hyaluronic acid-stearic acid conjugates and include a reactive oxygen species (ROS)-responsive thioketal linker. SIMs were designed to selectively accumulate at the site of inflammation and trigger drug release in the presence of ROS. Our in vitro studies in macrophages and in vivo studies in a murine model of colitis demonstrated that SIMs leverage HA-CD44 binding to target sites of inflammation. Oral delivery of SIMs to mice in both preventive and delayed therapeutic models ameliorated colitis's severity by reducing STING expression, suppressing the secretion of proinflammatory cytokines, enabling bodyweight recovery, protecting mice from colon shortening, and restoring colonic epithelium. In vivo end points combined with metabolomics identified key metabolites with a therapeutic role in reducing intestinal and mucosal inflammation. Our findings highlight the significance of programmable delivery platforms that downregulate inflammatory pathways at the intestinal mucosa for managing inflammatory bowel diseases.

Predicting the onset of preeclampsia by longitudinal monitoring of metabolic changes throughout pregnancy with Raman spectroscopy

Preeclampsia is a life-threatening pregnancy disorder. Current clinical assays cannot predict the onset of preeclampsia until the late 2nd trimester, which often leads to poor maternal and neonatal outcomes. Here we show that Raman spectroscopy combined with machine learning in pregnant patient plasma enables rapid, highly sensitive maternal metabolome screening that predicts preeclampsia as early as the 1st trimester with >82% accuracy. We identified 12, 15 and 17 statistically significant metabolites in the 1st, 2nd and 3rd trimesters, respectively. Metabolic pathway analysis shows multiple pathways corresponding to amino acids, fatty acids, retinol, and sugars are enriched in the preeclamptic cohort relative to a healthy pregnancy. Leveraging Pearson's correlation analysis, we show for the first time with Raman Spectroscopy that metabolites are associated with several clinical factors, including patients' body mass index, gestational age at delivery, history of preeclampsia, and severity of preeclampsia. We also show that protein quantification alone of proinflammatory cytokines and clinically relevant angiogenic markers are inadequate in identifying at-risk patients. Our findings demonstrate that Raman spectroscopy is a powerful tool that may complement current clinical assays in early diagnosis and in the prognosis of the severity of preeclampsia to ultimately enable comprehensive prenatal care for all patients.

Tumor-targeting cell membrane-coated nanorings for magnetic-hyperthermia-induced tumor ablation

Magnetic hyperthermia has attracted considerable attention for efficient cancer therapy because of its noninvasive nature, deep tissue penetration, and minimal damage to healthy tissues. Herein, we have fused cancer cell membrane fragments with lipids and cloaked them on magnetic nanorings to form targeted Fe nanorings (TF) for tumor-targeted magnetic hyperthermia-induced tumor ablation. In our approach, cell membrane fragments from cancer cells were fused with lipids to form vesicles, which could efficiently encapsulate magnetic nanorings, thereby forming TF. We observed that TF have high tumor uptake via homotypic targeting, where cancer cells take up TF through membrane fusion. Under an external alternating magnetic field (AMF), TF accumulated in the tumors are heated, driving magnetic-hyperthermia-induced tumor cell death. Our in vitro studies show that self-targeting TF efficiently localized in cancer cells and induced cell death with an AMF, which was shown by a live/dead assay. Our findings demonstrate the potential of TF in tumor ablation, thereby making them promising and efficient nanosystems for tumor-targeted theranostics.

Monitoring Metabolic Changes in Response to Chemotherapies in Cancer with Raman Spectroscopy and Metabolomics

Resistance to clinical therapies remains a major barrier in cancer management. There is a critical need for rapid and highly sensitive diagnostic tools that enable early prediction of treatment response to allow accurate clinical decisions. Here, Raman spectroscopy was employed to monitor changes in key metabolites as early predictors of response in KRAS-mutant colorectal cancer (CRC) cells, HCT116, treated with chemotherapies. We show at the single cell level that HCT116 is resistant to cetuximab (CTX), the first-line treatment in CRC, but this resistance can be overcome with pre-sensitization of cells with oxaliplatin (OX). In combination treatment of CTX + OX, sequential delivery of OX followed by CTX rather than simultaneous administration of drugs was observed to be critical for effective therapy. Our results demonstrated that metabolic changes are well aligned to cellular mechanical changes where Young's modulus decreased after effective treatment, indicating that both changes in mechanical properties and metabolism in cells are likely responsible for cancer proliferation. Raman findings were verified with mass spectrometry (MS) metabolomics, and both platforms showed changes in lipids, nucleic acids, and amino acids as predictors of resistance/response. Finally, key metabolic pathways enriched were identified when cells are resistant to CTX but downregulated with effective treatment. This study highlights that drug-induced metabolic changes both at the single cell level (Raman) and ensemble level (MS) have the potential to identify mechanisms of response to clinical cancer therapies.

First Trimester Prediction of Preterm Birth in Patient Plasma with Machine-Learning-Guided Raman Spectroscopy and Metabolomics

Preterm birth (PTB) is the leading cause of infant deaths globally. Current clinical measures often fail to identify women who may deliver preterm. Therefore, accurate screening tools are imperative for early prediction of PTB. Here, we show that Raman spectroscopy is a promising tool for studying biological interfaces, and we examine differences in the maternal metabolome of the first trimester plasma of PTB patients and those that delivered at term (healthy). We identified fifteen statistically significant metabolites that are predictive of the onset of PTB. Mass spectrometry metabolomics validates the Raman findings identifying key metabolic pathways that are enriched in PTB. We also show that patient clinical information alone and protein quantification of standard inflammatory cytokines both fail to identify PTB patients. We show for the first time that synergistic integration of Raman and clinical data guided with machine learning results in an unprecedented 85.1% accuracy of risk stratification of PTB in the first trimester that is currently not possible clinically. Correlations between metabolites and clinical features highlight the body mass index and maternal age as contributors of metabolic rewiring. Our findings show that Raman spectral screening may complement current prenatal care for early prediction of PTB, and our approach can be translated to other patient-specific biological interfaces.

The Emerging Role of Raman Spectroscopy as an Omics Approach for Metabolic Profiling and Biomarker Detection toward Precision Medicine

Omics technologies have rapidly evolved with the unprecedented potential to shape precision medicine. Novel omics approaches are imperative toallow rapid and accurate data collection and integration with clinical information and enable a new era of healthcare. In this comprehensive review, we highlight the utility of Raman spectroscopy (RS) as an emerging omics technology for clinically relevant applications using clinically significant samples and models. We discuss the use of RS both as a label-free approach for probing the intrinsic metabolites of biological materials, and as a labeled approach where signal from Raman reporters conjugated to nanoparticles (NPs) serve as an indirect measure for tracking protein biomarkers in vivo and for high throughout proteomics. We summarize the use of machine learning algorithms for processing RS data to allow accurate detection and evaluation of treatment response specifically focusing on cancer, cardiac, gastrointestinal, and neurodegenerative diseases. We also highlight the integration of RS with established omics approaches for holistic diagnostic information. Further, we elaborate on metal-free NPs that leverage the biological Raman-silent region overcoming the challenges of traditional metal NPs. We conclude the review with an outlook on future directions that will ultimately allow the adaptation of RS as a clinical approach and revolutionize precision medicine.

Physicochemical Properties and Route of Systemic Delivery Control the In Vivo Dynamics and Breakdown of Radiolabeled Gold Nanostars

The in vivo dynamics of nanoparticles requires a mechanistic understanding of multiple factors. Here, for the first time, the surprising breakdown of functionalized gold nanostars (F-AuNSs) conjugated with antibodies and 64 Cu radiolabels in vivo and in artificial lysosomal fluid ex vivo, is shown. The short-term biodistribution of F-AuNSs is driven by the route of systemic delivery (intravenous vs intraperitoneal) and long-term fate is controlled by the tissue type in vivo. In vitro studies including endocytosis pathways, intracellular trafficking, and opsonization, are combined with in vivo studies integrating a milieu of spectroscopy and microcopy techniques that show F-AuNSs dynamics is driven by their physicochemical properties and route of delivery. F-AuNSs break down into sub-20 nm broken nanoparticles as early as 7 days postinjection. Martini coarse-grained simulations are performed to support the in vivo findings. Simulations suggest that shape, size, and charge of the broken nanoparticles, and composition of the lipid membrane depicting various tissues govern the interaction of the nanoparticles with the membrane, and the rate of translocation across the membrane to ultimately enable tissue clearance. The fundamental study addresses critical gaps in the knowledge regarding the fate of nanoparticles in vivo that remain a bottleneck in their clinical translation.

Effects of retinoid-loaded hyaluronic acid nanomicelles on vaginal epithelium in a murine menopause model

PURPOSE

This study aimed to develop hyaluronic acid (HA)-based, retinoic acid (RA)-containing nanomicelles and to investigate the effects of these newly developed nanomicelles on regeneration of the vaginal epithelium and aquaporin 3 (AQP3) expression in a murine menopause model.

MATERIALS AND METHODS

The HA-based, RA-loaded nanomicelles were developed, and the RA-loading rate, encapsulation efficiency, and hydrodynamic diameter were measured. Female BALB/c mice (8 weeks; n=30) were divided into control and experimental groups. Menopause was established in the experimental group by removing both ovaries. The experimental group was further divided into an ovariectomy group, an HA-C18 vehicle group, and an HA-C18-RA group (2.5 µg per mouse); vaginal administration of HA-C18 or HA-C18-RA was performed once daily. After 4 weeks of treatment, murine vaginal tissue was removed, and histological analysis was performed.

RESULTS

Three drug-loaded nanomicelles were synthesized: the RA content in HA-C18-RA-10, HA-C18-RA-20, and HA-C18-RA-30 was 3.13%, 2.52%, and 16.67%, respectively, and the RA encapsulation efficiency was 95.57%, 83.92%, and 93.24%, respectively. In the experimental versus control group, serum estrogen levels were significantly reduced, and the vaginal mucosal epithelial layer was significantly thinner. After 4 weeks of treatment, the thickness of the vaginal mucosal epithelial layer and AQP3 expression was increased in the HA-C18-RA group compared with the HA-C18 vehicle group.

CONCLUSIONS

The newly developed HA-based nanomicelles containing RA resulted in vaginal epithelial recovery and increased AQP3 expression. The results may contribute to the development of functional vaginal lubricants or moisturizers for the treatment of vaginal dryness.

Nanomaterials for Natural Killer Cell-Based Immunoimaging and Immunotherapies in Cancer

Natural killer (NK) cells are an important component of the tumor immunosurveillance; activated NK cells can recognize and directly lyse tumor cells eliciting a potent antitumor immune response. Due to their intrinsic ability to unleash cytotoxicity against tumor cells, NK cell-based adoptive cell therapies have gained rapid clinical significance, and many clinical trials are ongoing. However, priming and activating NK cells, infiltration of activated NK cells in the immunosuppressive tumor microenvironment, and tracking the infiltrated NK cells in the tumors remain a critical challenge. To address these challenges, NK cells have been successfully interfaced with nanomaterials where the morphology, composition, and surface characteristics of nanoparticles (NPs) were leveraged to enable longitudinal tracking of NK cells in tumors or deliver therapeutics to prime NK cells. Distinct from other published reviews, in this tutorial review, we summarize the recent findings in the past decade where NPs were used to label NK cells for immunoimaging or deliver treatment to activate NK cells and induce long-term immunity against tumors. We discuss the NP properties that are key to surmounting the current challenges in NK cells and the different strategies employed to advance NK cells-based diagnostics and therapeutics. We conclude the review with an outlook on future directions in NP-NK cell hybrid interfaces, and overall clinical impact and patient response to such interfaces that need to be addressed to enable their clinical translation.

A Review of Different Vaccines and Strategies to Combat COVID-19

In December 2019, an unknown viral infection emerged and quickly spread worldwide, resulting in a global pandemic. This novel virus caused severe pneumonia and acute respiratory distress syndrome caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). It has caused 6.25 millions of deaths worldwide and remains a major concern for health, society, and the economy. As vaccination is one of the most efficient ways to combat this pandemic, different vaccines were developed in a short period. This review article discusses how coronavirus affected the top nations of the world and the vaccines being used for the prevention. Amongst the vaccines, some vaccines have already been approved, and some have been involved in clinical studies. The article also provides insight into different COVID-19 vaccine platforms, their preparation, working, efficacy, and side effects.

Inflammation-sensing catalase-mimicking nanozymes alleviate acute kidney injury via reversing local oxidative stress

Background

The reactive oxygen species (ROS) and inflammation, a critical contributor to tissue damage, is well-known to be associated with various disease. The kidney is susceptible to hypoxia and vulnerable to ROS. Thus, the vicious cycle between oxidative stress and renal hypoxia critically contributes to the progression of chronic kidney disease and finally, end-stage renal disease. Thus, delivering therapeutic agents to the ROS-rich inflammation site and releasing the therapeutic agents is a feasible solution.

Results

We developed a longer-circulating, inflammation-sensing, ROS-scavenging versatile nanoplatform by stably loading catalase-mimicking 1-dodecanethiol stabilized Mn₃O₄ (dMn₃O₄) nanoparticles inside ROS-sensitive nanomicelles (PTC), resulting in an ROS-sensitive nanozyme (PTC-M). Hydrophobic dMn₃O₄ nanoparticles were loaded inside PTC micelles to prevent premature release during circulation and act as a therapeutic agent by ROS-responsive release of loaded dMn₃O₄ once it reached the inflammation site.

Conclusions

The findings of our study demonstrated the successful attenuation of inflammation and apoptosis in the IRI mice kidneys, suggesting that PTC-M nanozyme could possess promising potential in AKI therapy. This study paves the way for high-performance ROS depletion in treating various inflammation-related diseases.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01410-z.

Light and immunostimulant mediated in-situ re-education of tumor-associated macrophages by photosensitizer conjugated mannan nanoparticles for boosting immuno-photodynamic anti-metastasis therapy

In an immunosuppressive tumor microenvironment, tumor-associated macrophages (TAMs) are the most abundant cells displaying pro-tumorigenic M2-like phenotypes, encouraging tumor growth and influencing the development of resistance against conventional therapies. TAMs...

Vimentin Targeted Nano-gene Carrier for Treatment of Renal Diseases

BACKGROUND

Chronic kidney disease (CKD) is a global health problem, and there is no permanent treatment for reversing kidney failure; thus, early diagnosis and effective treatment are required. Gene therapy has outstanding potential; however, the lack of safe gene delivery vectors, a reasonable transfection rate, and kidney targeting ability limit its application. Nanoparticles can offer innovative ways to diagnose and treat kidney diseases as they facilitate targetability and therapeutic efficacy.

METHODS

Herein, we developed a proximal renal tubule-targeting gene delivery system based on alternative copolymer (PS) of sorbitol and polyethyleneimine (PEI), modified with vimentin-specific chitobionic acid (CA), producing PS-conjugated CA (PSC) for targeting toward vimentin-expressing cells in the kidneys. In vitro studies were used to determine cell viability, transfection efficiency, serum influence, and specific uptake in the human proximal renal tubular epithelial cell line (HK-2). Finally, the targeting efficiency of the prepared PSC gene carriers was checked in a murine model of Alport syndrome.

RESULTS

Our results suggested that the prepared polyplex showed low cytotoxicity, enhanced transfection efficiency, specific uptake toward HK-2 cells, and excellent targeting efficiency toward the kidneys.

CONCLUSION

Collectively, from these results it can be inferred that the PSC can be further evaluated as a potential gene carrier for the kidney-targeted delivery of therapeutic genes for treating diseases.

Heat-Confined Tumor-Docking Reversible Thermogel Potentiates Systemic Antitumor Immune Response During Near-Infrared Photothermal Ablation in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) features immunologically "cold" tumor microenvironments with limited cytotoxic T lymphocyte (CTL) infiltration. Although ablation therapies have demonstrated modulation of "cold" TNBC tumors to inflamed "hot" tumors, recruitment of myeloid derived suppressor cells (MDSCs) at the tumors post ablation therapies prevents the infiltration of CTLs and challenge the antitumor potentials of T-cell therapies. Here, a thermal ablation immunotherapy strategy is developed to prevent the immune suppressive effects of MDSCs during photothermal ablation and induce a durable systemic antitumor immunity to eradicate TNBC tumors. An injectable pluronic F127/hyaluronic acid (HA)-based hydrogel embedded with manganese dioxide (BM) nanoparticles and TLR7 agonist resiquimod (R848) (BAGEL-R848), is synthesized to induce in situ laser-assisted gelation of the hydrogel and achieve desired ablation temperatures at a low laser-exposure time. Upon 808-nm laser irradiation, a significant reduction in the tumor burden is observed in BAGEL-R848-injected 4T1 tumor-bearing mice. The ablation induced immunogenic cell death and sustained release of R848 from BAGEL-R848 promotes dendritic cell maturation and reduced MDSCs localization in tumors. In addition, inflammatory M1 macrophages and CD8+IFN+ CTL are enriched in distant tumors in bilateral 4T1 tumor model, preventing metastatic tumor growth and signifying the potential of BAGEL-R848 to treat TNBC.

Glycol chitosan-based tacrolimus-loaded nanomicelle therapy ameliorates lupus nephritis

Background

Recently, we developed hydrophobically modified glycol chitosan (HGC) nanomicelles loaded with tacrolimus (TAC) (HGC-TAC) for the targeted renal delivery of TAC. Herein, we determined whether the administration of the HGC-TAC nanomicelles decreases kidney injury in a model of lupus nephritis. Lupus-prone female MRL/lpr mice were randomly assigned into three groups that received intravenous administration of either vehicle control, an equivalent dose of TAC, or HGC-TAC (0.5 mg/kg TAC) weekly for 8 weeks. Age-matched MRL/MpJ mice without Fas^lpr mutation were also treated with HGC vehicle and used as healthy controls.

Results

Weekly intravenous treatment with HGC-TAC significantly reduced genetically attributable lupus activity in lupus nephritis-positive mice. In addition, HGC-TAC treatment mitigated renal dysfunction, proteinuria, and histological injury, including glomerular proliferative lesions and tubulointerstitial infiltration. Furthermore, HGC-TAC treatment reduced renal inflammation and inflammatory gene expression and ameliorated increased apoptosis and glomerular fibrosis. Moreover, HGC-TAC administration regulated renal injury via the TGF-β1/MAPK/NF-κB signaling pathway. These renoprotective effects of HGC-TAC treatment were more potent in lupus mice compared to those of TAC treatment alone.

Conclusion

Our study indicates that weekly treatment with the HGC-TAC nanomicelles reduces kidney injury resulting from lupus nephritis by preventing inflammation, fibrosis, and apoptosis. This advantage of a new therapeutic modality using kidney-targeted HGC-TAC nanocarriers may improve drug adherence and provide treatment efficacy in lupus nephritis mice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00857-w.

Tumor Microenvironment-Regulating Immunosenescence-Independent Nanostimulant Synergizing with Near-Infrared Light Irradiation for Antitumor Immunity

The combination of photothermal therapy (PTT) and toll-like receptor (TLR)-mediated immunotherapy can elicit antitumor immunity and modulate the immunosuppressive tumor microenvironment (TME). Unlike other TLRs, TLR-5 is a promising target for immune activation, as its expression is well-maintained even during immunosenescence. Here, we developed a unique tumor microenvironment-regulating immunosenescence-independent nanostimulant consisting of TLR-5 adjuvant Vibrio vulnificus flagellin B (FlaB) conjugated onto the surface to an IR 780-loaded hyaluronic acid-stearylamine (HIF) micelles. These HIF micelles induced immune-mediated cell death via PTT when irradiated with a near-infrared laser. In comparison with PTT alone, the combination of in situ-generated tumor-associated antigens produced during PTT and the immune adjuvant FlaB demonstrated enhanced vaccine-like properties and modulated the TME by suppressing immune-suppressive regulatory cells (Tregs) and increasing the fraction of CD103+ migratory dendritic cells, which are responsible for trafficking tumor antigens to draining lymph nodes (DLNs). This combinatorial strategy (i.e., applying a TLR-5 adjuvant targeted to immunosenescence-independent TLR-5 and the in situ photothermal generation of tumor-associated antigens) is a robust system for next-generation immunotherapy and could even be applied in elderly patients, thus broadening the clinical scope of immunotherapy strategies.

External and Internal Stimuli-Responsive Metallic Nanotherapeutics for Enhanced Anticancer Therapy

Therapeutic, diagnostic, and imaging approaches based on nanotechnology offer distinct advantages in cancer treatment. Various nanotherapeutics have been presented as potential alternatives to traditional anticancer therapies such as chemotherapy, radiotherapy, and surgical intervention. Notably, the advantage of nanotherapeutics is mainly attributable to their accumulation and targeting ability toward cancer cells, multiple drug-carrying abilities, combined therapies, and imaging approaches. To date, numerous nanoparticle formulations have been developed for anticancer therapy and among them, metallic nanotherapeutics reportedly demonstrate promising cancer therapeutic and diagnostic efficiencies owing to their dense surface functionalization ability, uniform size distribution, and shape-dependent optical responses, easy and cost-effective synthesis procedure, and multiple anti-cancer effects. Metallic nanotherapeutics can remodel the tumor microenvironment by changing unfavorable therapeutic conditions into therapeutically accessible ones with the help of different stimuli, including light, heat, ultrasound, an alternative magnetic field, redox, and reactive oxygen species. The combination of metallic nanotherapeutics with both external and internal stimuli can be used to trigger the on-demand release of therapeutic molecules, augmenting the therapeutic efficacies of anticancer therapies such as photothermal therapy, photodynamic therapy, magnetic hyperthermia, sonodynamic therapy, chemodynamic therapy, and immunotherapy. In this review, we have summarized the role of different metallic nanotherapeutics in anti-cancer therapy, as well as their combinational effects with multiple stimuli for enhanced anticancer therapy.

Utilization of Polymer-Lipid Hybrid Nanoparticles for Targeted Anti-Cancer Therapy

Cancer represents one of the most dangerous diseases, with 1.8 million deaths worldwide. Despite remarkable advances in conventional therapies, these treatments are not effective to completely eradicate cancer. Nanotechnology offers potential cancer treatment based on formulations of several nanoparticles (NPs). Liposomes and polymeric nanoparticle are the most investigated and effective drug delivery systems (DDS) for cancer treatment. Liposomes represent potential DDS due to their distinct properties, including high-drug entrapment efficacy, biocompatibility, low cost, and scalability. However, their use is restricted by susceptibility to lipid peroxidation, instability, burst release of drugs, and the limited surface modification. Similarly, polymeric nanoparticles show several chemical modifications with polymers, good stability, and controlled release, but their drawbacks for biological applications include limited drug loading, polymer toxicity, and difficulties in scaling up. Therefore, polymeric nanoparticles and liposomes are combined to form polymer-lipid hybrid nanoparticles (PLHNPs), with the positive attributes of both components such as high biocompatibility and stability, improved drug payload, controlled drug release, longer circulation time, and superior in vivo efficacy. In this review, we have focused on the prominent strategies used to develop tumor targeting PLHNPs and discuss their advantages and unique properties contributing to an ideal DDS.

Self-Quenched Polysaccharide Nanoparticles with a Reactive Oxygen Species-Sensitive Cascade for Enhanced Photodynamic Therapy

Tumor microenvironment (TME)-responsive nanocarrier systems that keep the photosensitizer (PS) inactive during systemic circulation and then efficiently release or activate the PS in response to unique TME conditions have attracted much attention. Herein, we report novel TME-responsive, self-quenched polysaccharide nanoparticles (NPs) with a reactive oxygen species (ROS)-sensitive cascade. The PS, pheophorbide A (PhA), was conjugated to a water-soluble glycol chitosan (GC) through an ROS-sensitive thioketal (TK) linker. The amphiphilic GC-TK-PhA conjugates could arrange themselves into NPs and remain photoinactive due to their self-quenching effects. Upon reaching the ROS-rich hypoxic core of the tumor tissue, the NPs release the PS in a photoactive form by efficient, ROS-sensitive TK bond cleavage, thus generating potent phototoxic effects. Following near-infrared irradiation, the increase in locoregional ROS levels further accelerates the release and activation of PS. These cascade reactions caused a significant reduction in the tumor volume, demonstrating good antitumor potential.

Photo- and pH-Responsive Polycarbonate Block Copolymer Prodrug Nanomicelles for Controlled Release of Doxorubicin

Photo/pH dual-responsive amphiphilic diblock copolymers with alkyne functionalized pendant o-nitrobenzyl ester group are synthesized using poly(ethylene glycol) as a macroinitiator. The pendant alkynes are functionalized as aldehyde groups by the azide-alkyne Huisgen cycloaddition. The anticancer drug doxorubicin (DOX) molecules are then covalently conjugated through acid-sensitive Schiff-base linkage. The resultant prodrug copolymers self-assemble into nanomicelles in aqueous solution. The prodrug nanomicelles have a well-defined morphology with an average size of 20-40 nm. The dual-stimuli are applied individually or simultaneously to study the release behavior of DOX. Under UV light irradiation, nanomicelles are disassembled due to the ONB ester photocleavage. The light-controlled DOX release behavior is demonstrated using fluorescence spectroscopy. Due to the pH-sensitive imine linkage the DOX molecules are released rapidly from the nanomicelles at the acidic pH of 5.0, whereas only minimal amount of DOX molecules is released at the pH of 7.4. The DOX release rate is tunable by applying the dual-stimuli simultaneously. In vitro studies against colon cancer cells demonstrate that the nanomicelles show the efficient cellular uptake and the intracellular DOX release, indicating that the newly designed copolymers with dual-stimuli-response have significant potential applications as a smart nanomedicine against cancer.

Bioactivatable reactive oxygen species-sensitive nanoparticulate system for chemo-photodynamic therapy

Bioactivatable polymer nanoparticles (NPs) have attracted considerable attention as a prospective cancer therapy. Herein, we describe bioactivatable reactive oxygen species (ROS)-sensitive prodrug NPs designed to elicit spatiotemporally controlled, phototriggered chemo-photodynamic therapy. First, an effective anticancer agent, doxorubicin (DOX), was conjugated to poly(ethylene glycol) (PEG) via an ROS-responsive degradable thioketal (TK) linker. The resulting amphiphilic PEG-DOX conjugate (PEG-TK-DOX) self-assembled into a bioactivatable ROS-responsive NP system could efficiently encapsulate a hydrophobic photodynamic therapy (PDT) agent, pheophorbide A (PhA), with good colloidal stability and unimodal size distribution. Second, after the selective retention of NPs in the tumor, the site-specific release of DOX and PhA was spatiotemporally controlled, initially by endogenous ROS and subsequently by exogenous ROS produced during PDT. The locoregional treatment not only photoactivates PhA molecules to generate cytotoxic ROS but also triggers an ROS cascade, which accelerates the release of DOX and PhA via the ROS-mediated structural destruction of NPs, resulting in an enhanced anticancer therapeutic effect. This prodrug-NP system may function as an effective nanomedicine platform, working synergistically to maximize the efficacy of the combination of chemotherapy and photodynamic therapy with a remote-controlled release mechanism. STATEMENT OF SIGNIFICANCE: Photodynamic therapy (PDT) is a noninvasive therapy involving local ROS generation through the activation of photosensitizer (PS) molecules induced via external irradiation with near-infrared (NIR) light. Combinational therapies with PDT could synergistically enhance the therapeutic efficacy and overcome the limitations of monotherapy. In this study, we describe bioactivatable reactive oxygen species (ROS)-sensitive prodrug nanoparticles designed to elicit spatiotemporally controlled, photo triggered chemo-photodynamic therapy. Upon accumulation in tumor by enhanced permeation and retention (EPR) effect, the nanoparticles exhibited target-specific release of chemo-drug and photosensitizer in a spatiotemporally controlled cascade manner by endogenous ROS in the initial stage and the excessive production of exogenous ROS during PDT, leading to a further ROS cascade that accelerates the release of therapeutic cargo.

Long circulating photoactivable nanomicelles with tumor localized activation and ROS triggered self-accelerating drug release for enhanced locoregional chemo-photodynamic therapy

Although chemo-photodynamic therapy demonstrates promising synergetic therapeutic effect in malignant cancers, the currently available nanocarriers offer the limited capabilities for selective toxicity, drug release and tumor penetration. Herein, we developed photoactivatable nanomicelles, which are constructed by self-assembling of poly (ethylene glycol) (PEG)-stearamine (C18) conjugate (PTS) with a ROS-sensitive thioketal linker (TL) and co-loaded with doxorubicin (DOX) and photosensitizer pheophorbide A (PhA), for enhanced locoregional chemo-photodynamic therapy. Upon accumulation in tumor region, the resulting PTS nanomicelles loaded with Dox and PhA (PTS-DP) demonstrated reactive oxygen species (ROS) cascade responsive release of the DOX and PhA loaded inside. Initial intracellular release of DOX and PhA from the PTS-DP was triggered by the intrinsic presence of endogenous ROS within cancer cells. Furthermore, upon laser irradiation on the tumor region, enhanced singlet oxygen (¹O₂) was generated by PhA released initially in cancer cells, which in turns accelerated the cytoplasmic release of DOX through rapid dissociation of nanomicelles. The gradual elevation of local ROS level generated by light-activated PhA subsequent ROS-triggered release of DOX synergistically inhibited tumor growth and enhances the anti-tumor immunity. Findings of our study suggested that ROS-sensitive PTS nanomicelles could be a promising and innovative nanocarrier for locoregional chemo-photodynamic therapy.

Recent Advances in Nanovaccines Using Biomimetic Immunomodulatory Materials

The development of vaccines plays a vital role in the effective control of several fatal diseases. However, effective prophylactic and therapeutic vaccines have yet to be developed for completely curing deadly diseases, such as cancer, malaria, HIV, and serious microbial infections. Thus, suitable vaccine candidates need to be designed to elicit appropriate immune responses. Nanotechnology has been found to play a unique role in the design of vaccines, providing them with enhanced specificity and potency. Nano-scaled materials, such as virus-like particles, liposomes, polymeric nanoparticles (NPs), and protein NPs, have received considerable attention over the past decade as potential carriers for the delivery of vaccine antigens and adjuvants, due to their beneficial advantages, like improved antigen stability, targeted delivery, and long-time release, for which antigens/adjuvants are either encapsulated within, or decorated on, the NP surface. Flexibility in the design of nanomedicine allows for the programming of immune responses, thereby addressing the many challenges encountered in vaccine development. Biomimetic NPs have emerged as innovative natural mimicking biosystems that can be used for a wide range of biomedical applications. In this review, we discuss the recent advances in biomimetic nanovaccines, and their use in anti-bacterial therapy, anti-HIV therapy, anti-malarial therapy, anti-melittin therapy, and anti-tumor immunity.

Multimodal Composite Iron Oxide Nanoparticles for Biomedical Applications

Background

Iron oxide nanoparticles (IONPs) are excellent candidates for biomedical imaging because of unique characteristics like enhanced colloidal stability and excellent in vivo biocompatibility. Over the last decade, material scientists have developed IONPs with better imaging and enhanced optical absorbance properties by tuning their sizes, shape, phases, and surface characterizations. Since IONPs could be detected with magnetic resonance imaging, various attempts have been made to combine other imaging modalities, thereby creating a high-resolution imaging platform. Composite IONPs (CIONPs) comprising IONP cores with polymeric or inorganic coatings have recently been documented as a promising modality for therapeutic applications.

Methods

In this review, we provide an overview of the recent advances in CIONPs for multimodal imaging and focus on the therapeutic applications of CIONPs.

Result

CIONPs with phototherapeutics, IONP-based nanoparticles are used for theranostic application via imaging guided photothermal therapy.

Conclusion

CIONP-based nanoparticles are known for theranostic application, longstanding effects of composite NPs in in vivo systems should also be studied. Once such issues are fixed, multifunctional CIONP-based applications can be extended for theranostics of diverse medical diseases in the future.

"Navigate-dock-activate" anti-tumor strategy: Tumor micromilieu charge-switchable, hierarchically activated nanoplatform with ultrarapid tumor-tropic accumulation for trackable photothermal/chemotherapy

The delivery of therapeutics into tumors remains a challenge in nanoparticle-mediated drug delivery. However, effective therapies such as photothermal therapy (PTT) are limited by quick systemic clearance and non-specific biodistribution. Anti-tumor strategies tailored to accommodate both tumor accumulation/retention and cellular internalization under a single platform would be a promising strategy. This work demonstrates a hierarchical activating strategy that would exhibit enhanced circulation and rapid tumor-tropism as well as facilitate tumor penetration, followed by tumor-specific drug release to realize trackable photothermal/chemotherapy. Methods: We engineered a lithocholic acid-conjugated disulfide-linked polyethyleneimine micelle (LAPMi) loaded with paclitaxel (LAPMi-PTX, L), followed by the electrostatic adsorption of indocyanine green (ICG, I) on LAPMI-PTX and subsequently coated them with thermosensitive DPPC and DSPE-PEG-NH₂ lipids (L), producing Lipid/ICG/LAPMi-PTX (LIL-PTX) nanoparticles (NPs). The characteristics of NPs, including physicochemical characterization, photothermal & pH responsiveness, cell uptake, tumor spheroid penetration, anti-tumor efficacy and hierarchical activation of LIL-PTX NPs were investigated in vitro and in vivo by using CT26 cell line. The anti-metastatic potential of LIL-PTX NPs were demonstrated using 4T1 orthotopic tumor model. Results: The NPs synthesized possessed charge switchability in the mildly acidic pH, and were laser- and pH-responsive. Dual stimuli-responsive nature of LIL-PTX NPs improved the disposition of therapeutics to the tumor, reflected by enhanced intracellular uptake, tumor spheroid penetration and in vitro cytotoxicity studies. LIL-PTX NPs readily switched its surface charge from neutral to positive upon reaching the tumor milieu, thus resulting in rapid tumor tropism and accumulation. Under near-infrared laser irradiation, the thermosensitive lipids on LIL-PTX NPs were deshielded, and the tumor-penetrating LAPMi-PTX was subsequently exposed to the tumor milieu, thus resulting in enhanced intracellular internalization. Next, LAPMi-PTX evaded the endo-lysosomes, thereby releasing the PTX through the degradation of LAPMi mediated by intracellular GSH in the tumor. LIL-PTX NPs significantly improved the therapy by eradicating primary tumors completely and suppressing their subsequent lung metastasis. Conclusion: The improved therapeutic index is due to enhanced passive targeting by rapid tumor-tropic accumulation and tumor penetration by laser-driven exposure of LAPMi, thereby improving the therapeutic delivery for image-guided photothermal/chemotherapy.

Biopolymeric In Situ Hydrogels for Tissue Engineering and Bioimaging Applications

BACKGROUND

Biopolymeric in situ hydrogels play a crucial role in the regenerative repair and replacement of infected or injured tissue. They possess excellent biodegradability and biocompatibility in the biological system, however only a few biopolymeric in situ hydrogels have been approved clinically. Researchers have been investigating new advancements and designs to restore tissue functions and structure, and these studies involve a composite of biometrics, cells and a combination of factors that can repair or regenerate damaged tissue.

METHODS

Injectable hydrogels, cross-linking mechanisms, bioactive materials for injectable hydrogels, clinically applied injectable biopolymeric hydrogels and the bioimaging applications of hydrogels were reviewed.

RESULTS

This article reviews the different types of biopolymeric injectable hydrogels, their gelation mechanisms, tissue engineering, clinical applications and their various in situ imaging techniques.

CONCLUSION

The applications of bioactive injectable hydrogels and their bioimaging are a promising area in tissue engineering and regenerative medicine. There is a high demand for injectable hydrogels for in situ imaging.

Injectable Biomaterials in Plastic and Reconstructive Surgery: A Review of the Current Status

BACKGROUND

Injectable biomaterials have attracted increasing attention for volume restoration and tissue regeneration. The main aim of this review is to discuss the current status of the injectable biomaterials for correction of tissue defects in plastic and reconstructive surgery.

METHODS

Requirements of injectable biomaterials, mechanism of in situ gelation, characteristics, and the combinational usage of adipose-derived stem cells (ADSCs) and growth factors were reviewed.

RESULTS

The ideal injectable biomaterials should be biocompatible, non-toxic, easy to use, and cost-effective. Additionally, it should possess adequate mechanical properties and stability. In situ gelation method includes physical, chemical, enzymatic and photo-initiated methods. Natural and synthetic biomaterials carry their pros and cons due to their inherent properties. The combined use of ADSCs and growth factors provides enhanced potential for adipose tissue regeneration.

CONCLUSIONS

The usage of injectable biomaterials has been increasing for the tissue restoration and regeneration. The future of incorporating ADSCs and growth factors into the injectable biomaterials is promising.

Cell Membrane-Camouflaged Nanoparticles: A Promising Biomimetic Strategy for Cancer Theragnostics

Biomimetic functionalization of nanoparticles through camouflaging with cellular membranes has emerged as a promising strategy for cancer theragnostics. Cellular membranes used for camouflaging nanoparticles are generally isolated from blood cells, immune cells, cancer cells, and stem cells. The camouflaging strategy of wrapping nanoparticles with cellular membranes allows for superior tumor targeting through self-recognition, homotypic targeting and prolonged systematic circulation, thereby aiding in effective tumor therapy. In this review, we emphasized the various types of cellular membrane-camouflaged nanoparticles, their mechanisms in targeted therapy and various biomimetic strategies for anti-cancer therapy.

Tumor microenvironment-responsive nanoparticles for cancer theragnostic applications

BACKGROUND

Cancer is one of the deadliest threats to human health. Abnormal physiochemical conditions and dysregulated biosynthetic intermediates in the tumor microenvironment (TME) play a significant role in modulating cancer cells to evade or defend conventional anti-cancer therapy such as surgery, chemotherapy and radiotherapy. One of the most important challenges in the development of anti-tumor therapy is the successful delivery of therapeutic and imaging agents specifically to solid tumors.

MAIN BODY

The recent progresses in development of TME responsive nanoparticles offers promising strategies for combating cancer by making use of the common attributes of tumor such as acidic and hypoxic microenvironments. In this review, we discussed the prominent strategies utilized in the development of tumor microenvironment-responsive nanoparticles and mode of release of therapeutic cargo.

CONCLUSION

Tumor microenvironment-responsive nanoparticles offers a universal approach for anti-cancer therapy.

Dual-stimuli-responsive albumin-polyplex nanoassembly for spatially controlled gene release in metastatic breast cancer

Stimuli-responsive polymeric nanoparticles are useful for overcoming challenges such as transfection efficiency and the specific and safe delivery of genes to cancer cells. Transfection outcomes can be improved through spatially and temporally controlled gene release. We formulated a nanoassembly comprising a disulfide-crosslinked polyethylenimine (ssPEI) conjugated with a tumor-specific cell-penetrating peptide (DS 4-3) (SPD) polyplex and bovine serum albumin (BSA)-loaded IR780 (BI) nanoparticle, thereby forming a dual-stimulus-triggered, tumor-penetrating and gene-carrying nanoassembly (BI-SPD) via electrostatic complexing. BI-SPD nanoassembly were composed of highly stable nanosized complexes with an average size of 457 ± 27.5 nm, exhibiting an up to two-fold enhanced transfection efficiency with no sign of potential cytotoxicity in breast cancer cells. Moreover, upon laser irradiation, a four-fold increase in transfection efficiency was achieved due to the rapid endosomal escape of polyplexes triggered by the local heat induced by the BI-SPD nanoassembly. Additionally, the high redox environment in tumor cells facilitated the disassembly of the SPD polyplex for efficient plasmid release in the cytosol. The BI-SPD nanoassembly also exhibited high penetration and enhanced photothermally triggered gene expression in the 4T1 spheroid model. This BI-SPD nanoassembly has the potential to enhance the expression of therapeutic genes in tumor models without causing significant toxicity to surrounding healthy tissues, since it has shown higher tumor targeting and accumulation in the 4T1 tumor in mice model.

Synthesis and characterization of bioreducible cationic biarm polymer for efficient gene delivery

We synthesized a new cationic AB₂ miktoarm block copolymer consisting of one poly (ethylene glycol) (PEG) block and two cationic poly (l-lysine) (PLL) blocks, wherein the PLL blocks were conjugated to the PEG blocks with or without a bioreducible linker (disulfide bonds). Bioreducible and non-bioreducible miktoarm block copolymers (mPEG-(ss-PLL)₂ and mPEG-PLL₂) were prepared for efficient gene delivery as a non-viral gene delivery approach. Both cationic copolymers (bioreducible and nonbioreducible) efficiently formed the nanopolyplexes with plasmid DNA (pDNA) through electrostatic interaction at different weight ratio of polymer and pDNA. Gene condensation ability of the polymers and release of the DNA under reduction condition were measured by gel electrophoresis. Dynamic light scattering (DLS) and field-emission transmission electron microscopy (FE-TEM) were used to measure the average hydrodynamic diameter and morphology of the nanoparticles, respectively. The bioreducible nanopolyplexes showed lower cytotoxicity and higher gene expression than the non-reducible nanopolyplexes in cancer cells.

Injectable hydrogels for delivering biotherapeutic molecules

To date, numerous delivery systems based on either organic or inorganic material have been developed to achieve efficient and sustained delivery of therapeutics. Hydrogels, which are three dimensional networks of crosslinked hydrophilic polymers, have a significant role in solving the clinical and pharmacological limitations of present systems because of their biocompatibility, ease of preparation and unique physical properties such as a tunable porous nature and affinity for biological fluids. Development of an in situ forming injectable hydrogel system has allowed excellent spatial and temporal control, unlike systemically administered therapeutics. Injectable hydrogel systems can offset difficulties with conventional hydrogel-based drug delivery systems in the clinic by forming a drug/gene delivery or cell-growing depot in the body with a single injection, thereby enabling patient compliance and comfort. Carbohydrate polymers are widely used for the synthesis of injectable in situ-forming hydrogels because of ready availability, presence of modifiable functional groups, biocompatibility and other physiochemical properties. In this review, we discuss different aspects of injectable hydrogels, such as bulk hydrogels/macrogels, microgels, and nanogels derived from natural polymers, and their importance in the delivery of therapeutics such as genes, drugs, cells or other biomolecules and how these revolutionary systems can complement existing therapeutic delivery systems.

Green synthesis of bioactive polysaccharide-capped gold nanoparticles for lymph node CT imaging

The development of biologically targeted contrast agents for X-ray computed tomography (CT) imaging remains a major challenge. Here, we investigated a green chemistry-based synthesis of lymph node-targeted mannan-capped gold nanoparticles (M-GNPs) as a CT contrast agent. In this study, mannan was used as a reducing and stabilizing agent for gold nanoparticles (AuNPs). M-GNPs were readily internalized by antigen-presenting cells (APCs) through mannose receptors-mediated endocytosis. The M-GNPs, which had a spherical morphology, had an average diameter of 9.18±0.71nm and surface plasmon resonance (SPR) absorption spectra with maximal absorption at 522nm. The M-GNPs displayed a concentration-based X-ray attenuation property with a maximum Hounsfield unit (HU) value of 303.2±10.83. The local administration of M-GNPs led to significantly enhanced X-ray contrast for the imaging of popliteal lymph nodes. These findings demonstrated that M-GNPs can be used as biologically targeted contrast agents for CT imaging.

In vivo evaluation of cetuximab-conjugated poly(γ-glutamic acid)-docetaxel nanomedicines in EGFR-overexpressing gastric cancer xenografts

Epidermal growth factor receptor (EGFR), upregulated in gastric cancer patients, is an oncogene of interest in the development of targeted cancer nanomedicines. This study demonstrates in silico modeling of monoclonal antibody cetuximab (CET MAb)-conjugated docetaxel (DOCT)-loaded poly(γ-glutamic acid) (γ-PGA) nanoparticles (Nps) and evaluates the in vitro/in vivo effects on EGFR-overexpressing gastric cancer cells (MKN-28). Nontargeted DOCT-γ-PGA Nps (NT Nps: 110±40 nm) and targeted CET MAb-DOCT-γ-PGA Nps (T Nps: 200±20 nm) were prepared using ionic gelation followed by 1-Ethyl-3-(3-dimethyl aminopropyl)carbodiimide–N-Hydoxysuccinimide (EDC–NSH) chemistry. Increased uptake correlated with enhanced cytotoxicity induced by targeted Nps to EGFR +ve MKN-28 compared with nontargeted Nps as evident from MTT and flow cytometric assays. Nanoformulated DOCT showed a superior pharmacokinetic profile to that of free DOCT in Swiss albino mice, indicating the possibility of improved therapeutic effect in the disease model. Qualitative in vivo imaging showed early and enhanced tumor targeted accumulation of CET MAb-DOCT-γ-PGA Nps in EGFR +ve MKN-28–based gastric cancer xenograft, which exhibited efficient arrest of tumor growth compared with nontargeted Nps and free DOCT. Thus, actively targeted CET MAb-DOCT-γ-PGA Nps could be developed as a substitute to conventional nonspecific chemotherapy, and hence could become a feasible strategy for cancer therapy for EGFR-overexpressing gastric tumors.

pH/redox dual stimuli-responsive sheddable nanodaisies for efficient intracellular tumour-triggered drug delivery

A series of dual stimuli-responsive poly(l-histidine)_n-S-S-polyurethane-S-S-poly(l-histidine)_n [p(His)_n-SS-PU-SS-p(His)_n; n = 25, 35, 50, and 75] triblock copolymers that bear two pH-responsive p(His)_n end-blocks and PU middle-blocks tethered by a redox-responsive disulphide linker have been synthesized. The resulting triblock copolymers self-assemble to form micelles, nanodaisies (NDs), of uniform size (∼100 nm) and efficiently encapsulate the anticancer drug doxorubicin (Dox) with a high drug loading content (∼19%). The in vitro release profile shows an enhanced release of Dox in an acidic environment in the presence of 10 mM glutathione. The in vitro cell viability assays performed in various cell lines show that the NDs have no acute or intrinsic toxicity. Confocal microscopy images and flow cytometry results show the pH-responsive cellular uptake of Dox-loaded NDs, accelerated at pH ≤ 5.0. The tumour accumulation and in vivo bio-distribution studies of near-infrared dye (IR-820)-labeled NDs show higher tumour accumulation in CT26 tumour-bearing mice within 72 h. Furthermore, the Dox-loaded NDs effectively inhibit the CT26 tumours, suggesting that they are promising nanocarriers for cancer therapy.

Trigger-Responsive Gene Transporters for Anticancer Therapy

In the current era of gene delivery, trigger-responsive nanoparticles for the delivery of exogenous nucleic acids, such as plasmid DNA (pDNA), mRNA, siRNAs, and miRNAs, to cancer cells have attracted considerable interest. The cationic gene transporters commonly used are typically in the form of polyplexes, lipoplexes or mixtures of both, and their gene transfer efficiency in cancer cells depends on several factors, such as cell binding, intracellular trafficking, buffering capacity for endosomal escape, DNA unpacking, nuclear transportation, cell viability, and DNA protection against nucleases. Some of these factors influence other factors adversely, and therefore, it is of critical importance that these factors are balanced. Recently, with the advancements in contemporary tools and techniques, trigger-responsive nanoparticles with the potential to overcome their intrinsic drawbacks have been developed. This review summarizes the mechanisms and limitations of cationic gene transporters. In addition, it covers various triggers, such as light, enzymes, magnetic fields, and ultrasound (US), used to enhance the gene transfer efficiency of trigger-responsive gene transporters in cancer cells. Furthermore, the challenges associated with and future directions in developing trigger-responsive gene transporters for anticancer therapy are discussed briefly.

Stimuli-Regulated Smart Polymeric Systems for Gene Therapy

The physiological condition of the human body is a composite of different environments, each with its own parameters that may differ under normal, as well as diseased conditions. These environmental conditions include factors, such as pH, temperature and enzymes that are specific to a type of cell, tissue or organ or a pathological state, such as inflammation, cancer or infection. These conditions can act as specific triggers or stimuli for the efficient release of therapeutics at their destination by overcoming many physiological and biological barriers. The efficacy of conventional treatment modalities can be enhanced, side effects decreased and patient compliance improved by using stimuli-responsive material that respond to these triggers at the target site. These stimuli or triggers can be physical, chemical or biological and can be internal or external in nature. Many smart/intelligent stimuli-responsive therapeutic gene carriers have been developed that can respond to either internal stimuli, which may be normally present, overexpressed or present in decreased levels, owing to a disease, or to stimuli that are applied externally, such as magnetic fields. This review focuses on the effects of various internal stimuli, such as temperature, pH, redox potential, enzymes, osmotic activity and other biomolecules that are present in the body, on modulating gene expression by using stimuli-regulated smart polymeric carriers.

Bioreducible branched poly(modified nona-arginine) cell-penetrating peptide as a novel gene delivery platform

Cell-penetrating peptides (CPPs) have been widely used to deliver nucleic acid molecules. Generally, CPPs consisting of short amino acid sequences have a linear structure, resulting in a weak complexation and low transfection efficacy. To overcome these drawbacks, a novel type of CPP is required to enhance the delivery efficacy while maintaining its safe use at the same time. Herein, we report that a bioreducible branched poly-CPP structure capable of responding to reducing conditions attained both outstanding delivery effectiveness and selective gene release in carcinoma cells. Branched structures provide unusually strong electrostatic attraction between DNA and siRNA molecules, thereby improving the transfection capability through a tightly condensed form. We designed a modified type of nona-arginine (mR9) and synthesized a branched-mR9 (B-mR9) using disulfide bonds. A novel B-mR9/pDNA polyplex exhibited redox-cleavability and high transfection efficacy compared to conventional CPPs, with higher cell viability as well. B-mR9/VEGF siRNA polyplex exhibited significant serum stability and high gene-silencing effects in vitro. Furthermore, the B-mR9 polyplex showed outstanding tumor accumulation and inhibition ability in vivo. The results suggest that the bioreducible branched poly CPP has great potential as a gene delivery platform.