Association between toothbrushing and cardiovascular risk factors: a cross-sectional study using Korean National Health and Nutrition Examination Survey 2015-2017.

BACKGROUND: Previous studies have suggested that frequent toothbrushing is associated with a lower risk of future cardiovascular events. We sought to investigate further the relationship between toothbrushing, cardiovascular risk factors, and lifestyle behaviours. METHODS: We analysed a cross-sectional survey including 13,761 adults aged 30 years or older without a history of cardiovascular diseases from the Korean National Health and Nutritional Examination Survey. Conventional cardiovascular risk factors (blood pressure, lipid profiles, and fasting glucose), and inflammatory markers (high-sensitivity C-reactive protein [hsCRP], and white blood cell counts [WBC]) were investigated in relation to the frequency of toothbrushing. RESULTS: The estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk, calculated using the pooled cohort equations was 13.7%, 9.1%, and 7.3% for participants who reported toothbrushing 0-1, 2, and ≥ 3 times a day, respectively. Both conventional risk factors and inflammatory markers were significantly associated with frequent toothbrushing. However, after adjusting potential confounding factors such as age, sex, comorbidities, and lifestyle behaviours, only inflammatory markers were remained as significant factors. CONCLUSIONS: Oral hygiene behaviours are closely linked to cardiovascular risk factors. This study suggests that reduced systemic inflammatory burden may explain the benefit of improved oral hygiene in terms of cardiovascular risk.

Sustained Exosome-Guided Macrophage Polarization Using Hydrolytically Degradable PEG Hydrogels for Cutaneous Wound Healing: Identification of Key Proteins and MiRNAs, and Sustained Release Formulation.

Macrophages (Mφs) are characterized by remarkable plasticity, an essential component of chronic inflammation. Thus, an appropriate and timely transition from proinflammatory (M1) to anti-inflammatory (M2) Mφs during wound healing is vital to promoting resolution of acute inflammation and enhancing tissue repair. Herein, exosomes derived from M2-Mφs (M2-Exos), which contain putative key regulators driving Mφ polarization, are used as local microenvironmental cues to induce reprogramming of M1-Mφs toward M2-Mφs for effective wound management. As an injectable controlled release depot for exosomes, hydrolytically degradable poly(ethylene glycol) (PEG) hydrogels (Exogels) are designed and employed for encapsulating M2-Exos to maximize their therapeutic effects in cutaneous wound healing. The degradation time of the hydrogels is adjustable from 6 days or up to 27 days by controlling the crosslinking density and tightness. The localization of M2-Exos leads to a successful local transition from M1-Mφs to M2-Mφs within the lesion for more than 6 days, followed by enhanced therapeutic effects including rapid wound closure and increased healing quality in an animal model for cutaneous wound healing. Collectively, the hydrolytically degradable PEG hydrogel-based exosome delivery system may serve as a potential tool in regulating local polarization state of Mφs, which is crucial for tissue homeostasis and wound repair.

Improved oral hygiene care attenuates the cardiovascular risk of oral health disease: a population-based study from Korea.

AIMS: Oral health problems such as periodontal disease, dental caries, and tooth loss have been suggested to have associations with cardiovascular disease. This study aimed to evaluate whether oral hygiene behaviour can alleviate cardiovascular risk associated with oral health status using a nationwide population-based cohort. METHODS AND RESULTS: The data of 247 696 healthy adults aged 40 years or older who underwent an oral health screening programme and had no history of major cardiovascular events were extracted from the National Health Insurance System-National Health Screening Cohort. After a median follow-up of 9.5 years, 14 893 major cardiovascular events occurred including cardiac death, myocardial infarction, stroke, and heart failure. The risk of cardiovascular events was higher when a subject had periodontal disease, a higher number of dental caries, or more tooth loss. Performing one more tooth brushing a day was associated with a 9% significantly lower risk of cardiovascular events after multivariable adjustment. Regular dental visits (once a year or more) for professional cleaning were also shown to reduce cardiovascular risk by 14%. Improved oral hygiene behaviours were shown to attenuate the cardiovascular risk originating from periodontal disease, dental caries, and tooth loss. CONCLUSION: Oral hygiene care such as frequent tooth brushing and regular dental visits for professional cleaning reduced the risk of future cardiovascular events in healthy adults. This study also suggests that improved oral hygiene behaviour may modify the association between oral health and cardiovascular diseases.

Combination of bisacodyl suppository and 1 L polyethylene glycol plus ascorbic acid is a non-inferior and comfortable regimen compared to 2 L polyethylene glycol plus ascorbic acid.

BACKGROUND AND AIM: Appropriate bowel cleansing before colonoscopy is an important factor in increasing the detection rate of lesions. Low-volume polyethylene glycol (PEG) plus ascorbic acid (PEG-Asc) reduces the dosage of bowel preparation agent, but still presents discomfort to patients. The primary aim of the present study was to compare the efficacy of bowel cleansing between 2 L PEG-Asc (control) and 1 L PEG-Asc with bisacodyl suppository (suppository) groups, and the secondary aim was to investigate complications and tolerability between the two groups. METHODS: This was a single-center prospective randomized controlled study. We identified 168 patients scheduled for colonoscopy between August 2017 and January 2018 and randomly assigned them to the control or to the suppository groups. Efficacy of bowel cleansing was assessed using the Boston Bowel Preparation Scale (BBPS), and side-effects were surveyed using questionnaires. RESULTS: No significant difference was detected in baseline characteristics including insertion and withdrawal times, and adenoma detection rates between the two groups. Total BBPS score was 7.93 ± 1.06 and 7.74 ± 1.02 in the control and suppository groups, respectively (P = 0.22). Incidence of abdominal pain and nausea was not statistically different, whereas that of sleep disturbance and anal discomfort was higher in the control group. (P = 0.00). CONCLUSIONS: One liter PEG-Asc with bisacodyl suppository resulted in an equivalent bowel-cleansing outcome with reduced patient discomfort compared to 2 L PEG-Asc. Therefore, PEG-Asc with bisacodyl suppository represents a potential alternative and increases patient compliance with bowel preparation.

Sustained local delivery of oncolytic short hairpin RNA adenoviruses for treatment of head and neck cancer.

BACKGROUND: Oncolytic adenovirus (Ad)-mediated gene therapy is a promising approach for suppression of primary tumors. Therapeutic efficacy of Ad-mediated gene therapy has been limited by immunogenicity, rapid dissemination of viral progenies into systemic circulation and short duration of biological activity. Polymeric sustained local delivery can overcome many of these challenges to produce a viable therapy with improved outcomes. METHODS: Silk-elastinlike protein polymer (SELP) hydrogels were used for matrix-mediated delivery of oncolytic Ad, containing short hairpin RNA (shRNA) targeted to C-Met (sh-C-Met), to solid tumors in a nude mouse model of human head and neck cancer. The biological activity of Ad released from SELP hydrogels was examined as a function of time to investigate protective effects on viral activity. Antitumor efficacy and viral distribution were investigated for 3 weeks in tumor-bearing mice. RESULTS: The encapsulation of Ad with SELP hydrogels sustained biological activity longer than Ad alone. Ad in SELP matrix showed 1.5-fold greater antitumor efficacy compared to that of naked Ad in human xenograft tumor models. Histological analysis demonstrated that treatment with Ad in a SELP matrix resulted in apoptosis in a wider area of tumor tissue and higher density of Ad infection compared to Ad administered alone. CONCLUSIONS: Matrix-mediated delivery of Ad-containing shRNA with SELP hydrogels enhances therapeutic efficacy by tumor-selective infection, spatiotemporal control and preservation of biologic activity.

Hyaluronic acid-siRNA conjugate/reducible polyethylenimine complexes for targeted siRNA delivery.

The clinical applications of therapeutic siRNA remain as a challenge due to the lack of efficient delivery system. In the present study, hyaluronic acid-siRNA conjugate (HA-SS-siRNA)/reducible polyethylenimine (BPEI1.2k-SS) complexes were developed to efficiently deliver the siRNA to HA receptor abundant region with the improved siRNA stability. HA and siRNA were conjugated with disulfide bonds, which are cleavable in cytoplasm. The synthesized HA-SS-siRNA was further complexed with BPEI1.2k-SS, resulting in the formation of spherical nanostructures with approximately 190 nm of size and neutral surface charge. HA-SS-siRNA/BPEI1.2k-SS complexes exhibited the improved stability against serum proteins or polyanions. These complexes were successfully translocated into intracellular region via HA receptor-mediated endocytosis, and silenced target gene expression.

Design of PD-L1-Targeted Lipid Nanoparticles to Turn on PTEN for Efficient Cancer Therapy.

Lipid nanoparticles (LNPs) exhibit remarkable mRNA delivery efficiency, yet their majority accumulate in the liver or spleen after injection. Tissue-specific mRNA delivery can be achieved through modulating LNP properties, such as tuning PEGylation or varying lipid components systematically. In this paper, a streamlined method is used for incorporating tumor-targeting peptides into the LNPs; the programmed death ligand 1 (PD-L1) binding peptides are conjugated to PEGylated lipids via a copper-free click reaction, and directly incorporated into the LNP composition (Pep LNPs). Notably, Pep LNPs display robust interaction with PD-L1 proteins, which leads to the uptake of LNPs into PD-L1 overexpressing cancer cells both in vitro and in vivo. To evaluate anticancer immunotherapy mediated by restoring tumor suppressor, mRNA encoding phosphatase and tensin homolog (PTEN) is delivered via Pep LNPs to PTEN-deficient triple-negative breast cancers (TNBCs). Pep LNPs loaded with PTEN mRNA specifically promotes autophagy-mediated immunogenic cell death in 4T1 tumors, resulting in effective anticancer immune responses. This study highlights the potential of tumor-targeted LNPs for mRNA-based cancer therapy.

BioMatrix Versus Orsiro Stents for Coronary Artery Disease: A Multicenter, Randomized, Open-Label Study.

BACKGROUND: Comparative studies of ultrathin-strut biodegradable polymer sirolimus-eluting stent (BP-SES) have reported promising results and validated its excellent outcomes in terms of safety and efficacy. However, there are limited studies comparing BP drug-eluting stents with struts of different thicknesses. We compared the long-term clinical outcomes of patients treated with an ultrathin-strut BP-SES or a thick-strut biodegradable polymer biolimus-eluting stent (BP-BES). METHODS: The BIODEGRADE trial (Biomatrix and Orsiro Drug-Eluting Stents in Angiographic Result in Patients With Coronary Artery Disease) is a multicenter prospective randomized study comparing coronary revascularization in patients with ultrathin-strut BP-SES and thick-strut BP-BES with the primary end point of target lesion failure at 18 months posttreatment. We performed the prespecified analysis of 3-year clinical outcomes. RESULTS: In total, 2341 patients were randomized to receive treatment with ultrathin-strut BP-SES (N=1175) or thick-strut BP-BES (N=1166). The 3-year incidence rate of target lesion failure was 3.2% for BP-SES and 5.1% for BP-BES (P=0.023). The difference was primarily due to differences in ischemia-driven target lesion revascularization (BP-SES, 1.5%; BP-BES, 2.8%; P=0.035) between groups. A landmark analysis of the late follow-up period showed significant differences in target lesion failure, with outcomes being better in BP-SES. Cardiac death and target lesion revascularization were significantly lower in the BP-SES group. CONCLUSIONS: In a large, randomized trial, the long-term clinical outcome of target lesion failure at 3 years was significantly better among patients treated with the ultrathin-strut BP-SES. The results indicate the superiority of the ultrathin-strut BP-SES compared with the thick-strut BP-BES. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT02299011.

Bioreducible crosslinked polyelectrolyte complexes for MMP-2 siRNA delivery into human vascular smooth muscle cells.

PURPOSE: Bioreducible crosslinked polyplexes were prepared via disulfide bond formation after siRNA condensation with polyethylenimine-modified by deoxycholic acid (PEI-DA) to stabilize polyplex structure in an extracellular environment and to promote transfection efficiency in human smooth muscle cells (hSMCs). METHODS: The PEI-DA/siRNA polyplexes were further modified by crosslinking the primary amines of PEI with thiol-cleavable crosslinkers. The effect of disulfide crosslinked PEI-DA/siRNA (Cr PEI-DA/siRNA) polyplexes on target gene silencing was investigated by transfecting hSMCs with matrix metalloproteinase-2 (MMP-2) siRNA under serum conditions. The MMP-2 levels in the conditioned medium were examined using gelatin zymography. RESULTS: The Cr PEI-DA/siRNA polyplexes showed increased stability against heparin exchange reactions, while their disulfide linkages were successfully cleaved under reducing conditions. The polyplex crosslinking reaction led to a slight decrease in MMP-2 gene silencing activity in hSMCs due to the insufficient redox potential. However, the gene silencing efficiency of the Cr PEI-DA/siRNA polypexes was gradually improved in response to increasing intracellular reduction potential. The increased serum stability of the Cr PEI-DA/siRNA polyplexes resulted in significant enhancement of the intracellular delivery efficiency especially under serum conditions. CONCLUSION: The Cr PEI-DA/siRNA polyplex formulation may be a promising siRNA delivery system for the treatment of incurable genetic disorders.

Molecularly engineered siRNA conjugates for tumor-targeted RNAi therapy.

RNA interference (RNAi) is a major cellular mechanism regulating gene expression in which short double-stranded RNA molecules called small interfering RNA (siRNA) mediate sequence-specific mRNA degradation. RNAi technology has recently emerged as a promising therapeutic platform for the effective treatment of various diseases caused by inappropriate gene activity, such as cancer. However, the clinical translation of siRNA therapeutics has been hampered by the major hurdles associated with biological instability and limited delivery efficiency. Based on the various efforts, recent siRNA delivery strategies using cationic lipids and polymers allowed to enhance pharmacokinetics and delivery efficiency, resulting in potent and liver-targeted RNAi therapy. However, non-specific protein adsorption, high liver accumulation, and severe toxicity of cationic nanocarriers still limit the possibility of transfer of siRNA therapeutics from the laboratory to the clinic. One of the promising delivery strategies to overcome the limitations of siRNA therapeutics is carrier-free bioconjugation which is chemically modified and connected with biocompatible molecules such as lipids, peptides, antibodies, aptamers, and polymers. These molecularly engineered siRNA conjugates can be utilized for RNAi delivery to tissues beyond the liver, providing opportunities for clinical translation. This review focused on introducing the recent progress in molecularly engineered siRNA conjugates and their applications toward overcoming the limitations of siRNA for tumor-targeted delivery and therapy.

Self-assembled and nanostructured siRNA delivery systems.

A wide range of organic and inorganic materials have been used in the development of nano-scale self-assembling gene delivery systems to improve the therapeutic efficacy of nucleic acid drugs. Small interfering RNA (siRNA) has recently been recognized as a promising and potent nucleic acid medicine for the treatment of incurable genetic disorders including cancer; however, siRNA-based therapeutics suffer from the same delivery problems as conventional nucleic acid drugs such as plasmid DNA and antisense oligonucleotides. Many of the delivery strategies developed for nucleic acid drugs have been applied to siRNA therapeutics, but they have not produced satisfactory in vivo gene silencing efficiencies to warrant clinical trials. This review discusses recent progress in the development of self-assembled and nanostructured delivery systems for efficient siRNA-induced gene silencing and their potential application in clinical settings.

BioMatrix versus Orsiro biodegradable polymer stents in all-comer patients with coronary artery disease: the multicentre, randomised BIODEGRADE trial.

AIMS: The aim of this trial was to compare the safety and efficacy of a thin-strut biodegradable polymer sirolimus-eluting cobalt-chromium stent (Orsiro) to a thick-strut biodegradable polymer biolimus-eluting stent (BioMatrix). METHODS AND RESULTS: This randomised, open-label, non-inferiority trial was conducted among patients undergoing percutaneous coronary intervention. The primary endpoint was target lesion failure (TLF). Between July 2014 and September 2017, we randomly assigned 2,341 patients to BioMatrix stents (n=1,166) or Orsiro stents (n=1,175). We analysed 2,327 patients who completed 18-month follow-up. The mean patient age was 63.5 years, and 1,565 (67.3%) patients presented with acute coronary syndrome. At 18 months, 34 (2.9%) patients with BioMatrix stents and 24 (2.1%) with Orsiro stents experienced TLF (hazard ratio [HR] 0.70, upper limit of one-sided 95% confidence interval: 1.18, p for non-inferiority <0.0001). No significant differences were noted in rates of cardiac death (16 [1.4%] vs 12 [1.0%], p=0.558), target lesion-related myocardial infarction (0 [0%] vs 3 [0.3%], p=0.250), target lesion revascularisation (18 [1.6%] vs 10 [0.9%], p=0.124), or stent thrombosis (0 [0%] vs 2 [0.2%], p=0.50). CONCLUSIONS: In patients with a high prevalence of acute coronary syndrome, Orsiro stents were not inferior to BioMatrix stents. Both showed good clinical outcomes.

Reducible poly(amido ethylenimine)-based gene delivery system for improved nucleus trafficking of plasmid DNA.

In a nonviral gene delivery system, localization of a plasmid DNA in the nucleus is a prerequisite for expression of a desired therapeutic protein encoded in the plasmid DNA. In this study, a reducible polymer-based gene delivery system for improved intracellular trafficking and nuclear translocation of plasmid DNA is introduced. The system is consisted of two components, a plasmid DNA having repeated binding sequence for a karyophilic protein, NFkappaB, and a reducible polymer. A reducible poly(amido ethylenimine), poly(TETA-CBA), was synthesized by a Michael-type addition polymerization between cystamine bisacrylamide and triethyl tetramine. The polymer forming tight complexes with plasmid DNA could be degraded in the reductive cytosol to release the plasmid DNA. The triggered release mechanism in the cytosol could facilitate the interaction between cytosolic NFkappaB and the plasmid DNA having repeated NFkappaB biding motif. Upon activation of NFkappaB by interleukin-1beta (IL-1beta), most of the plasmid distributed in the cytoplasm was localized within the nucleus, resulting in significantly higher gene transfection efficiency than controls with nondegradable PEI. The current study suggests an alternative way of improving transfection efficiency by taking advantage of endogenous transport machinery for intracellular trafficking and nuclear translocation of a plasmid DNA.

Development of microRNA-21 mimic nanocarriers for the treatment of cutaneous wounds.

Rationale: Of the regulatory microRNAs expressed in the wounded skin, microRNA-21 (miR21) plays a pivotal role in wound repair by stimulating re-epithelialization, an essential feature to facilitate healing and reduce scar formation. Despite their crucial roles in wound healing, synthetic exogenous microRNAs have limited applications owing to the lack of an appropriate delivery system. Herein, we designed an miR21 mimic nanocarrier system using facial amphipathic bile acid-conjugated polyethyleneimines (BA-PEI) for the intracellular and transdermal delivery of synthetic miR21 molecules to accelerate wound repair. Methods: To design miR21 mimic nanocarriers, BA-conjugated PEIs prepared from three different types of BA at molar feed ratios of 1 and 3 were synthesized. The intracellular uptake efficiency of synthetic miR21 mimics was studied using confocal laser scanning microscopy and flow cytometry analysis. The optimized miR21/BA nanocarrier system was used to evaluate the wound healing effects induced by miR21 mimics in human HaCaT keratinocytes in vitro and a murine excisional acute wound model in vivo. Results: The cell uptake efficiency of miR21 complexed with BA-conjugated PEI was dramatically higher than that of miR21 complexed with PEI alone. Deoxycholic acid (DA)-modified PEI at a molar feed ratio of 3:1 (DA3-PEI) showed the highest transfection efficiency for miR21 without any increase in toxicity. After effective transdermal and intracellular delivery of miR21/DA3 nanocarriers, miR21 mimics promoted cell migration and proliferation through the post-transcriptional regulation of programmed cell death protein 4 (PDCD4) and matrix metalloproteinases. Thus, miR21 mimic nanocarriers improved both the rate and quality of wound healing, as evident from enhanced collagen synthesis and accelerated wound re-epithelialization. Conclusion: Our miRNA nanocarrier systems developed using DA3-PEI conjugates may be potentially useful for the delivery of synthetic exogenous miRNAs in various fields.

Intranasal delivery of cancer-targeting doxorubicin-loaded PLGA nanoparticles arrests glioblastoma growth.

Glioblastoma multiforme (GBM) is the most aggressive form of brain tumour and treatment is very challenging. Despite the recent advances in drug delivery systems, various approaches that allow sufficient deposition of anti-cancer drugs within the brain remain unsuccessful due to limited drug delivery throughout the brain. In this study, we utilised an intranasal (IN) approach to allow delivery of anti-cancer drug, encapsulated in PLGA nanoparticles (NPs). PLGA NPs were modified with the RGD ligand to enable Avß3 expressing tumour-specific delivery. IN delivery of RGD-conjugated-doxorubicin (DOX)-loaded-PLGA-nanoparticles (RGD-DOX-NP) showed cancer-specific delivery of NP and inhibition of brain tumour growth compared to the free-DOX or non-modified DOX-NP in the C6-implanted GBM model. Further, IN treatment with RGD-DOX-NP induces apoptosis in the tumour region without affecting normal brain cells. Our study provides therapeutic evidence to treat GBM using a non-invasive IN approach, which may further be translated to other brain-associated diseases.

Intravascular imaging analysis of a drug-eluting balloon followed by a bare metal stent compared to a drug-eluting stent for treatment of de novo lesions.

BACKGROUND/AIMS: After a study comparing drug-eluting stents (DESs) to sequential treatment with drug-eluting balloons (DEBs) and bare metal stents (BMSs), we retrospectively analysed strut malapposition and neointimal hyperplasia in de novo coronary lesions using optical coherence tomography (OCT) or intravascular ultrasonography (IVUS). METHODS: We obtained OCT data from 16 patients (eight per group) and IVUS data from 40 patients (20 per group). OCT or IVUS was performed after the index procedure and after 9 months. Parameters including obstruction volume due to neointimal hyperplasia (neointimal hyperplasia volume/stent volume, %), strut malapposition (% of malapposed struts), and intra-individual inhomogeneity of in-stent restenosis were compared. RESULTS: Although obstruction volume due to neointimal hyperplasia was significantly higher in the DEB-BMS group (14.90 ± 15.36 vs. DES 7.03 ± 11.39, p = 0.025), there was no difference in strut malapposition between the two groups (DEB-BMS 1.99 ± 5.37 vs. DES 0.88 ± 2.22, p = 0.856). The DEB-BMS group showed greater intra-individual inhomogeneity of in-stent restenosis pattern than the DES group. CONCLUSION: Treatment with DEB followed by BMS failed to improve strut malapposition despite higher in-stent neointimal growth, probably because of the inhomogeneous inhibition of in-stent neointimal hyperplasia by DEB. DEB technology should be improved to obtain even drug delivery to the vessel wall and homogeneous prevention of neointimal growth comparable to contemporary DES.

LHRH receptor-mediated delivery of siRNA using polyelectrolyte complex micelles self-assembled from siRNA-PEG-LHRH conjugate and PEI.

Polyelectrolyte complex (PEC) micelles modified with cancer cell targeting moieties were prepared for intracellular delivery of vascular endothelial growth factor (VEGF) small interfering RNA (siRNA). A luteinizing hormone-releasing hormone (LHRH) peptide analogue was coupled as a cancer targeting ligand to the distal end of the poly(ethylene glycol) (PEG)-siRNA conjugate. The siRNA-PEG-LHRH conjugate self-assembled to form nanosized PEC micelles upon mixing with poly(ethylenimine) (PEI) via ionic interactions. The PEC micelles showed spherical morphology with a hydrodynamic diameter of ca. 150 nm. For LHRH receptor overexpressing ovarian cancer cells (A2780), the PEC micelles with LHRH exhibited enhanced cellular uptake compared to those without LHRH, resulting in increased VEGF gene silencing efficiency via receptor-mediated endocytosis. This study showed that PEC micelles decorated with specific cell-recognizable targeting ligands could be used for targeted delivery of siRNA.

Amine-functionalized gold nanoparticles as non-cytotoxic and efficient intracellular siRNA delivery carriers.

Gold nanoparticles chemically modified with primary amine groups were developed as intracellular delivery vehicles for therapeutic small interfering RNA (siRNA). The positively charged gold nanoparticles could form stable polyelectrolyte complexes through electrostatic interactions with negatively charged siRNA-polyethylene glycol (PEG) conjugates having a cleavable di-sulfide linkage under reductive cytosol condition. The resultant core/shell type polyelectrolyte complexes surrounded by a protective PEG shell layer had a well-dispersed nanostructure with a hydrodynamic diameter of 96.3+/-25.9 nm, as determined by dynamic light scattering and transmission electron microscopy. Confocal laser scanning microscopy revealed that the nanosized polyelectrolyte complexes were efficiently internalized in human prostate carcinoma cells, and thus enhanced intracellular uptake of siRNA. Furthermore, the siRNA/gold complexes significantly inhibited the expression of a target gene within the cells without showing severe cytotoxicity. The current study demonstrated that positively charged gold nanoparticles could be potentially applied for intracellular delivery of siRNA.

Self-assembled PEGylated albumin nanoparticles (SPAN) as a platform for cancer chemotherapy and imaging.

Paclitaxel (PTX) is used as a major antitumor agent for the treatment of recurrent and metastatic breast cancer. For the clinical application of PTX, it needs to be dissolved in an oil/detergent-based solvent due to its poor solubility in an aqueous medium. However, the formulation often causes undesirable complications including hypersensitivity reactions and limited tumor distribution, resulting in a lower dose-dependent antitumor effect. Herein, we introduce a facile and oil-free method to prepare albumin-based PTX nanoparticles for efficient systemic cancer therapy using a conjugate of human serum albumin (HSA) and poly(ethyleneglycol) (PEG). PTX were efficiently incorporated in the self-assembled HSA-PEG nanoparticles (HSA-PEG/PTX) using a simple film casting and re-hydration procedure without additional processes such as application of high pressure/shear or chemical crosslinking. The spherical HSA-PEG nanoparticle with a hydrodynamic diameter of ca. 280 nm mediates efficient cellular delivery, leading to comparable or even higher cytotoxicity in various breast cancer cells than that of the commercially available Abraxane®. When systemically administered in a mouse xenograft model for human breast cancer, the HSA-PEG-based nanoparticle formulation exhibited an extended systemic circulation for more than 96 h and enhanced intratumoral accumulation, resulting in a remarkable anticancer effect and prolonged survival of the animals.