Controlled decoration of nanoceria on the surface of MoS2nanoflowers to improve the biodegradability and biocompatibility inDrosophila melanogastermodel.

In recent years, nanozymes based on two-dimensional (2D) nanomaterials have been receiving great interest for cancer photothermal therapy. 2D materials decorated with nanoparticles (NPs) on their surface are advantageous over conventional NPs and 2D material based systems because of their ability to synergistically improve the unique properties of both NPs and 2D materials. In this work, we report a nanozyme based on flower-like MoS2nanoflakes (NFs) by decorating their flower petals with NCeO2using polyethylenimine (PEI) as a linker molecule. A detailed investigation on toxicity, biocompatibility and degradation behavior of fabricated nanozymes in wild-typeDrosophila melanogastermodel revealed that there were no significant effects on the larval size, morphology, larval length, breadth and no time delay in changing larvae to the third instar stage at 7-10 d for MoS2NFs before and after NCeO2decoration. The muscle contraction and locomotion behavior of third instar larvae exhibited high distance coverage for NCeO2decorated MoS2NFs when compared to bare MoS2NFs and control groups. Notably, the MoS2and NCeO2-PEI-MoS2NFs treated groups at 100µg ml-1covered a distance of 38.2 mm (19.4% increase when compared with control) and 49.88 mm (no change when compared with control), respectively. High-resolution transmission electron microscopy investigations on the new born fly gut showed that the NCeO2decoration improved the degradation rate of MoS2NFs. Hence, nanozymes reported here have huge potential in various fields ranging from biosensing, cancer therapy and theranostics to tissue engineering and the treatment of Alzheimer's disease and retinal therapy.

MicroSPECT Imaging-Guided Treatment of Idiopathic Pulmonary Fibrosis in Mice with a Vimentin-Targeting 99mTc-Labeled N-Acetylglucosamine-Polyethyleneimine.

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with poor prognosis. Evidence has shown that vimentin is a key regulator of lung fibrogenesis. 99mTc-labeled N-acetylglucosamine-polyethyleneimine (NAG-PEI), a vimentin-targeting radiotracer, was used for the early diagnosis of IPF, and NAG-PEI was also used as a therapeutic small interfering RNA (siRNA) delivery vector for the treatment of IPF in this study. Single-photon emission-computed tomography (SPECT) imaging of bleomycin (BM)- and silica-induced IPF mice with 99mTc-labeled NAG-PEI was performed to visualize pulmonary fibrosis and monitor the treatment efficiency of siRNA-loaded NAG-PEI, lipopolysaccharide (LPS, a tolerogenic adjuvant), or zymosan (ZYM, an immunostimulant). The lung uptakes of 99mTc-NAG-PEI in the BM- and silica-induced IPF mice were clearly and directly correlated with IPF progression. The lung uptake of 99mTc-NAG-PEI in the NAG-PEI/TGF-ß1-siRNA treatment group or LPS treatment group was evidently lower than that in the control group, while the lung uptake of 99mTc-NAG-PEI was significantly higher in the ZYM treatment group compared to that in the control group. These results demonstrate that NAG-PEI is a potent MicroSPECT imaging-guided theranostic platform for IPF diagnosis and therapy.

A Radiolabeled Self-assembled Nanoparticle Probe for Diagnosis of Lung-Metastatic Melanoma.

Melanoma is a highly malignant skin cancer that frequently metastasizes to the lung, bone, and brain at an early phase. Therefore, noninvasive detection of metastasized melanoma could be beneficial to determine suitable therapeutic strategies. We previously reported a biocompatible ternary anionic complex composed of plasmid DNA (pDNA), polyethyleneimine (PEI), and γ-polyglutamic acid (γ-PGA) based on an electrostatic interaction, which was highly taken up by melanoma cells (B16-F10), even if it was negatively charged. Here, we developed a radiolabeled γ-PGA complex by using indium-111 (111In)-labeled polyamidoamine dendrimer (4th generation; G4) instead of pDNA and iodine-125 (125I)-labeled PEI instead of native PEI, and evaluated its effectiveness as a melanoma-targeted imaging probe. This ternary complex was synthesized at a theoretical charge ratio; carboxyl groups of 111In-diethylenetriaminepentaacetic acid (DTPA)-G4 : amino groups of 125I-PEI : carboxyl groups of γ-PGA was 1 : 8 : 16, and the size and zeta potential were approximately 29 nm and -33 mV, respectively. This complex was taken up by B16-F10 cells with time. Furthermore, a biodistribution study, using normal mice, demonstrated its accumulation in the liver, spleen, and lung, where macrophage cells are abundant. Almost the same level of radioactivity derived from both 111In and 125I was observed in these organs at an early phase after probe injection. Compared with the normal mice, significantly higher lung-to-blood ratios of radioactivity were observed in the B16-F10-lung metastatic cancer model. In conclusion, the radiolabeled γ-PGA complex would hold potentialities for nuclear medical imaging of lung metastatic melanoma.

Novel targets for sensitizing breast cancer cells to TRAIL-induced apoptosis with siRNA delivery.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in variety of cancer cells without affecting most normal cells, which makes it a promising agent for cancer therapy. However, TRAIL therapy is clinically not effective due to resistance induction. To identify novel regulators of TRAIL that can aid in therapy, protein targets whose silencing sensitized breast cancer cells against TRAIL were screened with an siRNA library against 446 human apoptosis-related proteins in MDA-231 cells. Using a cationic lipopolymer (PEI-αLA) for delivery of library members, 16 siRNAs were identified that sensitized the TRAIL-induced death in MDA-231 cells. The siRNAs targeting BCL2L12 and SOD1 were further evaluated based on the novelty and their ability to sensitize TRAIL induced cell death. Silencing both targets sensitized TRAIL-mediated cell death in MDA-231 cells as well as TRAIL resistant breast cancer cells, MCF-7. Combination of TRAIL and siRNA silencing BCL2L12 had no effect in normal human umbilical vein cells and human bone marrow stromal cell. The silencing of BCL2L12 and SOD1 enhanced TRAIL-mediated apoptosis in MDA-231 cells via synergistically activating capsase-3 activity. Hence, here we report siRNAs targeting BCL2L12 and SOD1 as a novel regulator of TRAIL-induced cell death in breast cancer cells, providing a new approach for enhancing TRAIL therapy for breast cancer. The combination of siRNA targeting BCL2L12 and TRAIL can be a highly effective synergistic pair in breast cancer cells with minimal effect on the non-transformed cells.

Intranasal delivery of Duox2 DNA using cationic polymer can prevent acute influenza A viral infection in vivo lung.

We studied the contribution of Duox2 in mucosal host defense against influenza A virus (IAV) infection in in vivo lung. We found that Duox2 was required for the induction of type I and III interferon (IFN)s and transient Duox2 overexpression using cationic polymer polyethyleneimine (PEI) leads to suppression of IAV infection in in vivo lung. Twenty mice (C57BL/6J) were anesthetized and challenged by intranasal administration of 213 pfu/30 µl of IAV (WS/33/H1N1), and IAV-infected mice were euthanized at 1, 3, 5, 7, 10, 14 days post infection (dpi). Duox2 small hairpin RNA (shRNA) and pCMV-Duox2 formulated with PEI were inoculated to mice to assess the regulatory mechanism between Duox2 and IFN secretion. Following intranasal IAV inoculation, viral infection was significantly aggravated from 3 dpi in in vivo lung and viral titer was highest at 7 dpi. Consistent with this, Duox2 messenger RNA (mRNA) and protein expressions were significantly induced from 3 dpi in the lung tissue of IAV-infected mice. Viral titer was much higher in IAV-infected mice that were inoculated with Duox2 shRNA accompanied with lower survival rate and extensive lung pathologies. Interestingly, severe lung pathologies in IAV-infected mice were not observed and viral titer was significantly reduced in mice with pulmonary administration of pCMV-Duox2 formulated with PEI before IAV inoculation. Both mRNA and secreted protein levels of IFN-ß and IFN-λ2/3 were highly elevated in IAV-infected mice with pCMV-Duox2 formulated with PEI. Duox2 is necessary for the regulation of IFN secretion in in vivo lung, and pulmonary administration of Duox2 DNA using cationic polymer triggers the induction of type I and III IFNs resulting in more complete suppression of IAV infection.

Enhanced delivery of naproxen to the viable epidermis from an activated poly N-isopropylacrylamide (PNIPAM) Nanogel: Skin penetration, modulation of COX-2 expression and rat paw oedema.

Stimulus-responsive drug-loaded poly (N-isopropylacrylamide) nanogels were examined as a means of enhancing the delivery of naproxen into skin ex vivo. Following massaging into skin, the epidermis was probed (with and without base activation) for depth penetration and transdermal delivery of drug, and anti-inflammatory activity in the relative levels of COX-2 expression. Rat paw oedema testing was used to determine anti-inflammatory effects in vivo. When activated by sodium carbonate, particle size reduced by 19%. Tape stripping revealed significantly greater delivery of naproxen into the epidermis for the activated nanogel and the steady state flux was enhanced 2.8-fold. With base-activation COX-2 was 50% lower than non-activated, and this trend was confirmed by immunostaining, and by the reduction of rat paw swelling which provided ex vivo - in vivo corroboration. A mechanism of action is proposed. In conclusion, stimulus-responsive nanogels have potential for enhancing dermal drug delivery and therapeutic outcomes in inflammatory skin diseases.

Polyethyleneimine and Chitosan Polymer-Based Mucoadhesive Liquid Crystalline Systems Intended for Buccal Drug Delivery.

The buccal mucosa is accessible, shows rapid repair, has an excellent blood supply, and shows the absence of the first-pass effect, which makes it a very attractive drug delivery route. However, this route has limitations, mainly due to the continuous secretion of saliva (0.5 to 2 L/day), which may lead to dilution, possible ingestion, and unintentional removal of the active drug. Nanotechnology-based drug delivery systems, such as liquid crystalline systems (LCSs), can increase drug permeation through the mucosa and thereby improve drug delivery. This study aimed at developing and characterizing the mechanical, rheological, and mucoadhesive properties of four liquid crystalline precursor systems (LCPSs) composed of four different aqueous phases (i) water (FW), (ii) chitosan (FC), (iii) polyethyleneimine (FP), or (iv) both polymers (FPC); oleic acid was used as the oil phase, and ethoxylated and propoxylated cetyl alcohol was used as the surfactant. Polarized light microscopy and small-angle X-ray scattering indicated that all LCPSs formed liquid crystalline states after incorporation of saliva. Rheological, texture, and mucoadhesive assays showed that FPC had the most suitable characteristics for buccal application. In vitro release study showed that FPC could act as a controlled drug delivery system. Finally, based on in vitro cytotoxicity data, FPC is a safe buccal drug delivery system for the treatment of several buccal diseases.

Intracellular delivery and passive tumor targeting of a self-assembled nanogel containing carborane clusters for boron neutron capture therapy.

Boron neutron capture therapy, based on the release of thermal neutron irradiation from boron, is a targeted radiation therapy for cancer. Targeted and sufficient accumulation of boron in tumor cells to achieve cytotoxic efficacy and reduce off-target effects remains a challenge. Carborane has been investigated for use as a delivery agent in boron neutron capture therapy because of its high boron content and chemical stability; however, it is cytotoxic, making safe delivery difficult. The aim of this study was to investigate the potential of carborane-bearing pullulan nanogels to safely and effectively deliver boron to tumor cells in vitro and in vivo and, consequently, assess their potential as a boron neutron capture therapeutic. Murine fibrosarcoma cells (CMS5a) were used for in vitro investigations of nanogel cytotoxicity, cell uptake. A mouse fibrosarcoma xenograft model was used to investigate the bio-distribution of nanogels after intravenous administration. The nanogels produced no apparent cytotoxicity and underwent cell uptake in CMS5a cells after a 24 h incubation at up to 2000 µg/mL and 400 µg/mL, respectively. The internalized nanogels were localized around the nuclear membrane. The nanogels were administered intravenously to mice bearing fibrosarcoma xenografts. Nanogel tumor localization likely occurred through the enhanced permeation and retention effect. The nanogels successfully reduced the cytotoxicity of carborane, were internalized into tumor cells, acted as a dual-delivery therapeutic and accumulated in tumors in vivo. Consequently, they demonstrate significant potential as a boron neutron capture therapeutic.

PEGylated Cationic Vectors Containing a Protease-Sensitive Peptide as a miRNA Delivery System for Treating Breast Cancer.

Several targeted drug delivery systems have recently been developed to increase the bioavailability of a drug at its site of action, allowing simultaneous reduction of the total necessary drug dose as well as side effects. Here, we designed a cationic gene vector containing matrix metalloproteinase-2 (MMP2)-cleavable substrate peptides that specifically target tumor sites where MMP2 levels are high. The targeted delivery system is fabricated by linking enzyme-cleavable polyethylene glycol (PEG) derivatives to cationic ß-cyclodextrin-polyethylenimine conjugates, which reduce the toxicity of polyethylenimine and condense the therapeutic cargo. In the present study, tumor suppressor microRNA miR-34a, which suppresses onset and progression of many types of cancers, was investigated for its therapeutic potential for treating breast cancer. The PEG coating markedly reduces nonspecific interaction between cationic particles and serum proteins, permitting accumulation at the target site; subsequent peptide cleavage by MMP2 facilitates miR-34a delivery into tumor cells. The nanopreparation shows excellent stability, and its internalization, tumor targeting, and antitumor efficacy in vitro and in vivo are better than those of a nanopreparation containing MMP2-uncleavable peptide.

A phase I trial of intraperitoneal GEN-1, an IL-12 plasmid formulated with PEG-PEI-cholesterol lipopolymer, administered with pegylated liposomal doxorubicin in patients with recurrent or persistent epithelial ovarian, fallopian tube or primary peritoneal cancers: An NRG Oncology/Gynecologic Oncology Group study.

OBJECTIVE: The study's purpose was to assess safety and efficacy of escalating doses of weekly GEN-1 with pegylated liposomal doxorubicin (PLD) in patients with recurrent or persistent epithelial ovarian, fallopian tube or primary peritoneal cancers (EOC). METHODS: Patients had persistent or recurrent platinum-resistant EOC. The trial was a standard 3+3 phase I dose escalation design with patients receiving intravenous PLD 40mg/m2 (dose level 1 and 2) or 50mg/m2 (dose level 3) every 28days and intraperitoneal GEN-1 at 24mg/m2 (dose level 1) or 36mg/m2 (dose level 2 and 3) on days 1, 8, 15, and 22 of a 28day cycle. Cycles were repeated every 28days until disease progression. Patients were monitored for toxicity, clinical efficacy, and evidence of systemic and intraperitoneal immunologic effect. RESULTS: Sixteen evaluable patients received a median of 4cycles (range 1-8). No dose limiting toxicities were found. The adverse side effects were 4 grade 3 anemia, 2 grade 3 abdominal pain, 7 grade 3 neutropenia, and 2 grade 4 neutropenia. A clinical benefit of 57.1% (PR=21.4%; SD=35.7%) was found in the 14 patients with measurable disease. The highest number of partial responses (28.6%) and stable disease (57.1%) were found at dose level 3. The maximum tolerated dose was not reached. Increases in IL-12, IFN-γ, and TNF-α levels were found in peritoneal fluid following GEN-1 treatment. CONCLUSIONS: GEN-1 in combination with PLD has encouraging clinical benefit and biological activity in recurrent or persistent EOC and warrants further investigation with escalating doses of GEN-1.

Cutting Edge: Nanogel-Based Delivery of an Inhibitor of CaMK4 to CD4+ T Cells Suppresses Experimental Autoimmune Encephalomyelitis and Lupus-like Disease in Mice.

Treatment of autoimmune diseases is still largely based on the use of systemically acting immunosuppressive drugs, which invariably cause severe side effects. Calcium/calmodulin-dependent protein kinase IV is involved in the suppression of IL-2 and the production of IL-17. Its pharmacologic or genetic inhibition limits autoimmune disease in mice. In this study, we demonstrate that KN93, a small-molecule inhibitor of calcium/calmodulin-dependent protein kinase IV, targeted to CD4(+) T cells via a nanolipogel delivery system, markedly reduced experimental autoimmune encephalomyelitis and was 10-fold more potent than the free systemically delivered drug in the lupus mouse models. The targeted delivery of KN93 did not deplete T cells but effectively blocked Th17 cell differentiation and expansion as measured in the spinal cords and kidneys of mice developing experimental autoimmune encephalomyelitis or lupus, respectively. These results highlight the promise of cell-targeted inhibition of molecules involved in the pathogenesis of autoimmunity as a means of advancing the treatment of autoimmune diseases.

Polyethyleneimine-treated polyacrylonitrile membrane hemofilter for critically ill patients receiving anticoagulant-free prolonged intermittent renal replacement therapy: a single-center, prospective, self-controlled pilot study.

BACKGROUND: Critically ill patients requiring renal replacement therapy (RRT) are at risk of disease-related bleeding. Systemic heparinization should be avoided. AN69ST, a polyethyleneimine-treated polyacrylonitrile (AN69) membrane hemofilter, can be primed with heparin, improving its local anticoagulative activity. Prolonged intermittent RRT (PI-RRT) is of shorter duration and cheaper, considered as an alternative to continuous RRT. This study was performed to compare the success rate of anticoagulant-free PI-RRT using AN69ST versus AN69 membrane hemofilter. We also evaluated risk factors for filter clotting. METHODS: This crossover, double-blind, randomized study included patients requiring PI-RRT but at high bleeding risk treated with AN69ST and AN69 hemo filters. The success rate of RRT, filter lifespan and severity of filter clotting were compared between the hemo filters. Factors associated with the filter clotting risk were analyzed with a Cox proportional hazards model. RESULTS: This study included 60 patients (mean age, 68.1 ± 15.8 years). Thirty-three (55.0%) patients were in the intensive care unit, 34 (56.8%) had disease-related thrombocytopenia, and 14 (23.3%) had local hemorrhagic diseases. The success rate of PI-RRT with the AN69ST and AN69 hemofilter was 51.7% and 50.9%, respectively (P > 0.05). The mean PI-RRT duration was 543.1 ± 119.0 min in the completed sessions and 387.3 ± 140.8 min in the prematurely terminated sessions, without significant difference between AN69ST and AN69 hemofilters. Cox regression analysis showed that age (odds ratio [OR], 1.023 per year), platelet count (OR, 1.07 per 10 × 109/L), hemoglobin concentration (OR, 1.035 per 1 g/L), and activated partial thromboplastin time (aPTT; OR, 0.973 per second) were associated with a hemofilter clotting risk. The AN69ST hemofilter lifespan was significantly prolonged averaging an extra 251.7 min in patients with an aPTT of <35.3 s, hemoglobin concentration of >83 g/L and platelet count of <70 × 109/L. CONCLUSIONS: Anticoagulant-free PI-RRT by a heparin-primed AN69ST hemofilter reached a 51.7% success rate. The risk of premature clotting of the extracorporeal circuit remains unsatisfactory. For select patients at high risk of bleeding, the heparin-primed AN69ST hemofilter may be more appropriate for anticoagulation-free PI-RRT. TRIAL REGISTRATION: https://www.clinicaltrials.gov ; study number: NCT02355873 . Release Date 01/21/2015.

Efficacy, safety and mechanism of HP-ß-CD-PEI polymers as absorption enhancers on the intestinal absorption of poorly absorbable drugs in rats.

CONTEXT: Oral bioavailability of some hydrophilic therapeutic macromolecules was very poor, thus leading to their limited application in clinic. OBJECTIVE: To investigate the efficacy, safety and mechanism of HP-ß-CD-PEI polymers on the intestinal absorption of some poorly absorbable drugs in rats. METHODS: Effects of HP-ß-CD-PEI polymers on the intestinal absorptions of drugs were investigated by an in situ closed loop method in rats. The safety of HP-ß-CD-PEI polymer was evaluated by measurement of lactate dehydrogenase (LDH) activity and amount of protein released from rat intestinal perfusate. The absorption enhancing mechanisms were explored by the measurement of zeta potential, transepithelial electrical resistance (TEER) and in vitro transport of FD4 (a paracellular marker) across rat intestinal membranes, respectively. RESULTS: HP-ß-CD-PEI polymers, especially HP-ß-CD-PEI1800, demonstrated excellent absorption enhancing effects on drug absorption in a concentration-dependent manner and the enhancing effect was more efficient in the small intestine than that in the large intestine. Five percent (w/v) HP-ß-CD-PEI1800 obviously decreased the TEER, accompanied with increase in the intestinal transport of FD4, indicating that absorption enhancing actions of HP-ß-CD-PEI polymers were possibly performed by loosening tight junctions of intestinal epithelium cells, thereby increasing drug permeation via a paracellular pathway. A good liner relationship between absorption enhancing effects of HP-ß-CD-PEI polymers and their zeta potentials suggested the contribution of positive charge on the surface of these polymers to their absorption enhancing effects. CONCLUSION: HP-ß-CD-PEI polymers might be potential and safe absorption enhancers for improving oral delivery of poorly absorbable macromolecules including peptides and proteins.

Delivery of Thermoresponsive-Tailored Mixed Micellar Nanogel of Lidocaine and Prilocaine with Improved Dermatokinetic Profile and Therapeutic Efficacy in Topical Anaesthesia.

The topical delivery of local anaesthetics has always been a difficult task due to the limited percutaneous absorption of local anaesthetic drugs across the various barriers of the skin. In this pursuit, a thermoresponsive mixed micellar nanogel (MMNG) system of lidocaine and prilocaine has been attempted in the current piece of work. The system relies on the ability to alter its phase state (sol-to-gel) for feasibility of the topical application in response to change in temperature. The composition of MMNG entails majorly of Pluronic® F127 and Tween 80 in a fixed combination so as to provide the desired thermoreversibility for the skin application. The gels were optimized with respect to phase transition temperature (T sol/gel), turbidity and viscosity. The optimized systems were then characterized for particle size, spreadability, syringeability, bioadhesive strength, ex vivo skin permeation, retention and dermatokinetic studies. The skin compatibility revealed that no histological changes were observed for optimized formulation, while the conventional system showed changes in the skin-tissues. Further, the enhanced intensity of anaesthetic effect was noted in an in vivo rabbit model and tail flick model in mice. The overall results suggest that the prepared MMNG system possesses the potential in providing an efficacious, safe and acceptable alternative therapeutic system for topical anaesthesia.

The effects of transfection reagent polyethyleneimine (PEI) and non-targeting control siRNAs on global gene expression in human aortic smooth muscle cells.

BACKGROUND: RNA interference (RNAi) is a powerful platform utilized to target transcription of specific genes and downregulate the protein product. To achieve effective silencing, RNAi is usually applied to cells or tissue with a transfection reagent to enhance entry into cells. A commonly used control is the same transfection reagent plus a "noncoding RNAi". However, this does not control for the genomic response to the transfection reagent alone or in combination with the noncoding RNAi. These control effects while not directly targeting the gene in question may influence expression of other genes that in turn alter expression of the target. The current study was prompted by our work focused on prevention of vascular bypass graft failure and our experience with gene silencing in human aortic smooth muscle cells (HAoSMCs) where we suspected that off target effects through this mechanism might be substantial. We have used Next Generation Sequencing (NGS) technology and bioinformatics analysis to examine the genomic response of HAoSMCs to the transfection reagent alone (polyethyleneimine (PEI)) or in combination with commercially obtained control small interfering RNA (siRNAs) (Dharmacon and Invitrogen). RESULTS: Compared to untreated cells, global gene expression of HAoSMcs after transfection either with PEI or in combination with control siRNAs displayed significant alterations in gene transcriptome after 24 h. HAoSMCs transfected by PEI alone revealed alterations of 213 genes mainly involved in inflammatory and immune responses. HAoSMCs transfected by PEI complexed with siRNA from either Dharmacon or Invitrogen showed substantial gene variation of 113 and 85 genes respectively. Transfection of cells with only PEI or with PEI and control siRNAs resulted in identification of 20 set of overlapping altered genes. Further, systems biology analysis revealed key master regulators in cells transfected with control siRNAs including the cytokine, Interleukin (IL)-1, transcription factor GATA Binding Protein (GATA)-4 and the methylation enzyme, Enhancer of zeste homolog 2 (EZH-2) a cytokine with an apical role in initiating the inflammatory response. CONCLUSIONS: Significant off-target effects in HAoSMCs transfected with PEI alone or in combination with control siRNAs may lead to misleading conclusions concerning the effectiveness of a targeted siRNA strategy. The lack of structural information about transfection reagents and "non coding" siRNA is a hindrance in the development of siRNA based therapeutics.

Folate Receptor Targeted Delivery of siRNA and Paclitaxel to Ovarian Cancer Cells via Folate Conjugated Triblock Copolymer to Overcome TLR4 Driven Chemotherapy Resistance.

This paper focuses on the ability of a folate-decorated triblock copolymer to deliver a targeted dose of siRNA in order to overcome chemotherapy resistance which can commonly cause complications in ovarian cancer patients. The micelleplexes that are formed upon electrostatic interaction with siRNA are used to deliver siRNA in a targeted manner to SKOV-3 ovarian cancer cells that overexpress folate receptor-α (FRα). The triblock copolymer consists of polyethylenimine-graft-polycaprolactone-block-poly(ethylene glycol) (PEI-g-PCL-b-PEG-Fol). In this work, polymers of different molecular weights of PEG, as well as different grafting degrees of the (g-PCL-b-PEG-Fol) chains to PEI, were analyzed to optimize targeted siRNA delivery. The polymers, their micelleplexes, and the in vitro performance of the latter were characterized by nuclear magnetic resonance, dynamic light scattering, transmission electron microscopy, flow cytrometry, western blot, confocal microscopy, and in luciferase assays. The different PEI-g-PCL-b-PEG-Fol conjugates showed suitable sizes below 260 nm, especially at N/P 5, which also allowed for full siRNA condensation. Furthermore, flow cytometry and Western blot analysis demonstrated that our best polymer was able to effectively deliver siRNA and that siRNA delivery resulted in efficient protein knockdown of toll-like receptor 4 (TLR4). Consequently, TLR4 knock down within SKOV-3 cells resensitized them toward paclitaxel (PTX) treatment, and apoptotic events increased. This study demonstrates that PEI-g-PCL-b-PEG-Fol conjugates are a reliable delivery system for siRNA and are able to mediate therapeutic protein knockdown within ovarian cancer cells. Additionally, this study provides further evidence to link TLR4 levels to chemotherapy resistance.

Vitamin E-Labeled Polyethylenimine for in vitro and in vivo Gene Delivery.

A series of Vitamin E (vitE)-labeled PEIs (PEI-vitEn) were synthesized and showed excellent complexation ability with plasmid DNA (pDNA). The cellular uptake of PEI-vitEn/pDNA complexes was greatly enhanced with the increase of vitE labeling, which is much better than that of control PEI25 in three different cell lines. PEI-vitE6 showed the best performance in gfp pDNA delivery and following GFP expression in HEK-293A cells. In addition, in vivo gene delivery in living mice also confirmed that PEI-vitE6 showed low toxicity and efficiently delivered gfp pDNA to the cells of liver and lung tissues for gene expression.

Delivery of tanshinone IIA and α-mangostin from gold/PEI/cyclodextrin nanoparticle platform designed for prostate cancer chemotherapy.

A new anti-cancer drug delivery system, based on gold nanoparticles, has been designed for hydrophobic active compounds. The system is a conjugate of gold/polyethyleneimine (AuNPs/PEI) nanoparticles and sulphated ß-cyclodextrin (CD). Anionic cyclodextrin was attached to the positively charged AuNPs/PEI nanoparticles by ionic bonds. Tanshinone IIA and α-mangostin were extracted, purified and encapsulated into the AuNPs/PEI/CD nanoparticles. In vitro preliminary cell viability assays against prostate cancer cell lines PC-3 and DU145 showed that encapsulation resulted in increased cytotoxicity.

Inhibition of breast cancer with transdermal tamoxifen-encapsulated lipoplex.

BACKGROUND: Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER) positive breast cancer in pre- and post-menopausal women. However, using tamoxifen routinely to inhibit endogenous or exogenous estrogen effects is occasionally difficult because of its potential side effects. OBJECTIVES: The aim of this study is to design a local drug delivery system to encapsulate tamoxifen for observing their efficacy of skin penetration, drug accumulation and cancer therapy. METHODS: A cationic liposome-PEG-PEI complex (LPPC) was used as a carrier for the encapsulation of tamoxifen and forming 'LPPC/TAM' for transdermal release. The cytotoxicity of LPPC/TAM was analyzed by MTT. The skin penetration, tumor growth inhibition and organ damages were measured in xenograft mice following transdermal treatment. RESULTS: LPPC/TAM had an average size less than 270 nm and a zeta-potential of approximately 40 mV. LPPC/TAM displayed dramatically increased the cytotoxic activity in all breast cancer cells, especially in ER-positive breast cancer cells. In vivo, LPPC drug delivery helped the fluorescent dye penetrating across the skim and accumulating rapidly in tumor area. Administration of LPPC/TAM by transdermal route inhibited about 86 % of tumor growth in mice bearing BT474 tumors. This local treatment of LPPC/TAM did not injury skin and any organs. CONCLUSION: LPPC-delivery system provided a better skin penetration and drug accumulation and therapeutic efficacy. Therefore, LPPC/TAM drug delivery maybe a useful transdermal tool of drugs utilization for breast cancer therapy.

Development, optimization, and characterization of a novel tea tree oil nanogel using response surface methodology.

PURPOSE: To develop and optimize nanoemulsion (NE)-based emulgel (EG) formulation as a potential vehicle for topical delivery of tea tree oil (TTO). METHODOLOGY: Central composite design was adopted for optimizing the processing conditions for NE preparation by high energy emulsification method viz. surfactant concentration, co-surfactant concentration, and stirring speed. The optimized NE was developed into emulgel (EG) using pH sensitive polymer Carbopol 940 and triethanolamine as alkalizer. The prepared EG was evaluated for its pH, viscosity, and texture parameters, ex vivo permeation at 37 °C and stability. Antimicrobial evaluation of EG in comparison to conventional gel and pure TTO was also carried out against selected microbial strains. RESULTS AND DISCUSSION: Optimized NE had particle size and zeta potential of 16.23 ± 0.411 nm and 36.11 ± 1.234 mV, respectively. TEM analysis revealed the spherical shape of droplets. The pH of EG (5.57 ± 0.05 ) was found to be in accordance with the range of human skin pH. EG also illustrated efficient permeation (79.58 µL/cm(2)) and flux value (JSS) of 7.96 µL cm(2)/h through skin in 10 h. Viscosity and texture parameters, firmness (9.3 ± 0.08 g), spreadability (2.26 ± 0.06 mJ), extrudability (61.6 ± 0.05 mJ), and adhesiveness (8.66 ± 0.08 g) depict its suitability for topical application. Antimicrobial evaluation of EG with same amount of TTO as conventional gel revealed broader zones of growth inhibitions against all the selected microbial strains. Moreover, EG was also found to be nonirritant (PII 0.0833). These parameters were consistent over 90 d. CONCLUSION: TTO EG turned out to be a promising vehicle for the topical delivery of TTO with enhanced therapeutic efficacy.