Alveolar macrophage-derived vascular endothelial growth factor contributes to allergic airway inflammation in a mouse asthma model

Vascular endothelial growth factor (VEGF) is a potent proangiogenic factor that correlates with vascular permeability and remodelling in asthma. Recently, alveolar macrophages (AM) were shown to be an important source of VEGF during lung injury. Our previous studies demonstrated that AM are an important subset of macrophages in the initiation of asthmatic symptoms. Here, we further investigated whether AM-derived VEGF was required for allergic airway inflammation in asthma. In this study, we reported that the expression of VEGF in AM was significantly increased after allergen challenge. Depleting AM or neutralizing VEGF in alveolus prevented ovalbumin (OVA)-induced asthma-related inflammation by inhibiting the infiltration of inflammatory cells in the lung, reduced the level of the cytokines, IL-4, IL-5, and IL-13, in the bronchoalveolar lavage fluid (BALF) and decreased airway hyperresponsiveness (AHR). Moreover, the inhibition of miR-20b increased the protein level of VEGF in normal AM; conversely, increasing miR-20b in asthmatic AM resulted in decreased VEGF protein levels. These findings suggest that AM-derived VEGF is necessary for allergic airway inflammation in asthmatic mice and miR-20b negatively regulates this expression.

IL-12 and IL-10 production are differentially regulated by phosphatidylinositol 3-kinase in mast cells

The cellular mechanisms that directly regulate the production of pro- and anti-inflammatory cytokines after lipopolysaccharide (LPS) stimulation in mast cells are currently unresolved. The aim of this study was to clarify the role of phosphatidylinositol 3-kinase (PI3K) in the production of IL-12 and IL-10 in mouse bone marrow-derived mast cells (BMMCs), stimulated with Escherichia coli-derived LPS. LPS activates the PI3K signalling pathway; analysis of cytokine production following LPS stimulation of BMMCs revealed that inhibition of the PI3K pathway differentially regulated IL-10 and IL-12 syntheses. IL-12 production was enhanced, whereas IL-10 levels were suppressed. Inhibition of LPS-mediated activation of the PI3K pathway resulted in a pronounced reduction of NF-κB activity that was dependent on IκBα phosphorylation. These findings demonstrate a regulatory function for PI3K in modulating IL-10 and IL-12 production in mast cells and provide insight into how engagement of the PI3K pathway affects the induction of key immunoregulatory cytokines that control both qualitative and quantitative aspects of early inflammation.

Preparation, characterization and in vivo evaluation of pH-sensitive oral insulin-loaded poly(lactic-co-glycolicacid) nanoparticles

AIM

Oral administration of insulin is a promising drug delivery system for diabetic patients as it is convenient and reduces pain, two of the major contributors to non-compliance.

METHODS

In this study, insulin was encapsulated in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) by using double-emulsion/solvent evaporation technique and analyses on its release kinetics were carried out using both in vitro and in vivo methods.

RESULTS

First, only by this simple methods, release speed of insulin from NPs can be controlled in different pH solution. The rate of release of insulin was found to be slower in acidic pH; about 90% of insulin was released in 11 days at pH 1.0. In alkaline conditions, the release was faster; about 90% release was observed to occur within 3 days at pH 7.8. The insulin-loaded poly (lactic-co-glycolic acid) nanoparticles (PINPs) were administered orally to diabetes mellitus-induced rats and the response of blood glucose and insulin levels was estimated. Blood glucose decreased and the concentration of insulin in animal blood increased. In diabetic animals which were administered intermittent insulin, every 8 h, blood glucose levels were maintained equivalently with those of healthy rats.

CONCLUSION

These experimental results indicated that oral PINPs are able to deliver insulin effectively and decrease animal blood sugar; in conclusion, this may be a promising delivery system for the treatment of diabetes.

Origin of strong white electroluminescence from dense Si nanodots embedded in silicon nitride

Strong white electroluminescence (EL) from SiN-based devices containing Si nanodots with a density of more than 4.6×10(12)cm(2) was investigated. The white EL illustrates enhanced light emission with increasing applied voltage and can be divided into two components, a dominant peak at ~710 nm and weak one at ~550 nm, which are close to those of the PL spectra optically pumped by the 325 and 488 nm lines, respectively. Based on the PL characteristics, we propose that the dominant EL band arises from the band-to-band recombination in the dense Si nanodots where quantum confinement plays a decisive role in the light emission, whereas the weak EL band originates from the radiative Si dangling bond (K⁰) centers in the silicon nitride matrix.

Overexpression of Arabidopsis dehydration- responsive element-binding protein 2C confers tolerance to oxidative stress

Dehydration-responsive element-binding proteins (DREBs)regulate plant responses to environmental stresses. In the current study, transcription of DREB2C, a class 2 Arabidopsis DREB, was induced by a superoxide anion propagator, methyl viologen (MV). The oxidative stress tolerance of DREB2C-overexpressing transgenic plants was significantly greater than that of wild-type plants, as measured by ion leakage and chlorophyll fluorescence under light conditions. The transcriptional activity of several ascorbate peroxidase (APX) genes as well as APX protein activity was induced in DREB2C overexpressors. Additionally, the level of H2O2 in the overexpressors was lower than in wt plants under similar oxidative stress conditions. An electrophoretic mobility shift assay and transient activator reporter assay showed that APX2 expression was regulated by heat shock factor A3 (HsfA3) and that HsfA3 is regulated at the transcriptional level by DREB2C. These results suggest that DREB2C plays an important role in promoting oxidative stress tolerance in Arabidopsis.

A genome-wide survey of copy number variation regions in various chicken breeds by array comparative genomic hybridization method

The discovery of copy number variation (CNV) in the genome has provided new insight into genomic polymorphism. Studies with chickens have identified a number of large CNV segments using a 385k comparative genomic hybridization (CGH) chip (mean length >140 kb). We present a detailed CNV map for local Chinese chicken breeds and commercial chicken lines using an Agilent 400k array CGH platform with custom-designed probes. We identified a total of 130 copy number variation regions (CNVRs; mean length = 25.70 kb). Of these, 104 (80.0%) were novel segments reported for the first time in chickens. Among the 104 novel CNVRs, 56 (53.8%) of the segments were non-coding sequences, 65 (62.5%) showed the gain of DNA and 40 (38.5%) showed the loss of DNA (one locus showed both loss and gain). Overlapping with the formal selective sweep data and the quantitative trait loci data, we identified four loci that might be considered to be high-confidence selective segments that arose during the domestication of chickens. Compared with the CNVRs reported previously, genes for the positive regulation of phospholipase A2 activity were discovered to be significantly over-represented in the novel CNVRs reported here by gene ontology analysis. Availability of our results should facilitate further research in the study of the genetic variability in chicken breeds.

The mechanism of memory impairment induced by Aβ chronic administration involves imbalance between cytokines and neurotrophins in the rat hippocampus

It has been demonstrated that the onset and progression of Alzheimer's disease (AD) are associated with inflammatory disorders in the brain. Although the interactions of inflammatory cytokines with neurotrophins have been reported in vitro, the balance change between inflammatory cytokines and neurotrophic factors (NTFs), such as nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), and glial cell line-derived neurotrophic factor (GDNF), due to amyloid β (Aβ) chronic administration in vivo is still unclear. The hypothesis of the present study was that the accumulation of Aβ activated glial cells to produce inflammatory mediators and NTFs to maintain the neurons survival, however the failure of crosstalk between NTFs and inflammatory cytokines might occur in the brain and the NTFs expressions would decrease after Aβ chronic treatment, which, therefore, would contribute to the neuronal death and memory impairments. Thus, the present study measured the learning and memory behavior, glial cells activities, cytokines (IL-1α, IL-1β and TNF-α) concentrations and NTFs (NGF, BDNF and GDNF) gene and protein levels in rats after i.c.v injection of Aβ(25-35) for 14 days. The results showed that Aβ (25-35)-treated animals exhibited failure of balance between inflammatory cytokines and NTFs system (increased cytokines levels, decreased NGF protein expression and reduced NTFs gene transcriptions), which might contribute to the cognitive impairments. The findings from this study provide valuable evidence that correct regulation of the crosstalk between inflammatory cytokines and NTFs could be a direction for AD therapy in the future.

P1-12-13: Comparative Pharmacokinetics (PK) of Trastuzumab Emtansine (T-DM1) in Patients Who Have or Who Have Not Received Prior Treatment for Human Epidermal Growth Factor 2 (HER2)-Positive Metastatic Breast Cancer (MBC)

Background: T-DM1, an antibody-drug conjugate composed of trastuzumab, a stable linker, and the cytotoxic agent DM1, is in development for the treatment of HER2−positive cancers. Single-agent T-DM1 3.6 mg/kg every 3 weeks (q3w) has demonstrated clinical activity in 2 phase II studies (TDM4258g and TDM4374g) in patients with pretreated HER2−positive MBC. The efficacy and safety of T-DM1 vs trastuzumab + docetaxel was investigated in patients with no prior MBC treatment in the randomized phase II study TDM4450g/BO21976. Here we report the PK of T-DM1 from that study and compare these data with those from studies that enrolled pretreated patients.

Methods: In all 3 studies, PK parameters, including maximum concentration (Cmax), area under the concentration-time curve (AUC), terminal half-life (t½), steady-state volume of distribution (Vss), and clearance (CL) were estimated by noncompartmental analysis (NCA) for serum T-DM1, serum total trastuzumab (conjugated and unconjugated), and plasma DM1. The effects of baseline trastuzumab and HER2 extracellular domain (ECD) concentration on T-DM1 exposure were explored and the relationship between T-DM1 exposure and clinical response (objective response rate [ORR] and progression-free survival [PFS]) was modeled.

Results: T-DM1 PK from evaluable patients enrolled in 3 studies are shown in Table 1. No significant correlations were observed between efficacy (as measured by ORR) and T-DM1 exposure (AUC, Cmax) after administration of T-DM1 to pretreated patients; efficacy-exposure analyses (ORR and PFS) for previously untreated patients will be presented. Patients with measurable concentrations of trastuzumab at baseline had a greater AUC during cycle 1; however, this did not impact ORR. Baseline circulating HER2 ECD concentrations also had no effect on ORR for pretreated patients. The impact of baseline trastuzumab and HER2 ECD concentrations on ORR and PFS in previously untreated patients will be presented.

Proximity induced enhancement of the Curie temperature in hybrid spin injection devices

We investigate the increase of the Curie temperature T(C) in a lateral spin injection geometry where the ferromagnetic (Ga,Mn)As injector and detector contacts are capped by a thin iron film. Because of interlayer coupling between Fe and (Ga,Mn)As T(C) gets enhanced by nearly 100% for the thinnest (Ga,Mn)As films. The use of the proximity effect might pave the way for practical implementation of spintronic devices.

Paraquat induces epigenetic changes by promoting histone acetylation in cell culture models of dopaminergic degeneration

Environmental neurotoxic exposure to agrochemicals has been implicated in the etiopathogenesis of Parkinson's disease (PD). The widely used herbicide paraquat is among the few environmental chemicals potentially linked with PD. Since epigenetic changes are beginning to emerge as key mechanisms in neurodegenerative diseases, herein we examined the effects of paraquat on histone acetylation, a major epigenetic change in chromatin that can regulate gene expression, chromatin remodeling, cell survival and cell death. Exposure of N27 dopaminergic cells to paraquat induced histone H3 acetylation in a time-dependent manner. However, paraquat did not alter acetylation of another core histone H4. Paraquat-induced histone acetylation was associated with decreased total histone deacetylase (HDAC) activity and HDAC4 and 7 protein expression levels. To determine if histone acetylation plays a role in paraquat-induced apoptosis, the novel HAT inhibitor anacardic acid was used. Anacardic acid treatment significantly attenuated paraquat-induced caspase-3 enzyme activity, suppressed proteolytic activation and kinase activity of protein kinase C delta (PKCδ) and also blocked paraquat-induced cytotoxicity. Together, these results demonstrate that the neurotoxic agent paraquat induced acetylation of core histones in cell culture models of PD and that the inhibition of HAT activity by anacardic acid protects against apoptotic cell death, indicating that histone acetylation may represent key epigenetic changes in dopaminergic neuronal cells during neurotoxic insults.

Coenzyme Q plays opposing roles on bacteria/fungi and viruses in Drosophila innate immunity

Coenzyme Q (CoQ or ubiquinone) is a lipid-soluble component of virtually all types of cell membranes and has been shown to play multiple metabolic functions. Several clinical diseases including encephalomyopathy, cerebellar ataxia and isolated myopathy were shown to be associated with CoQ deficiency. However, the role of CoQ in immunity has not been defined. In the present study, we showed that flies defective in CoQ biosynthetic gene coq2 were more susceptible to bacterial and fungal infections, while were more resistant to viruses. We found that Drosophila contained both CoQ9 and CoQ10, and food supplement of CoQ10 could partially rescue the impaired immune functions of coq2 mutants. Surprisingly, wild-type flies fed CoQ10 became more susceptible to viral infection, which suggested that extra caution should be taken when using CoQ10 as a food supplement. We further showed that CoQ was essential for normal induction of anti-microbial peptides and amplification of viruses. Our work determined CoQ content in Drosophila and described its function in immunity for the first time.

Prognostic factors and survial of advanced renal cell carcinoma with predominant sarcomatoid histology

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Background: Sarcomatoid renal cell carcinoma (SRCC) is known to have aggressive clinical course and poor response to treatment. Very limited data of clinical feature, prognostic factor, and survival are available for advanced disease with predominant sarcomatoid histology. We evaluated clinical features, response to treatment, and prognostic factors for survival.

Methods: Between 2001 and 2010, 30 patients with metastatic or recurrent RCC with predominant sarcomatoid histology (sarcomatoid component 30% or more for resected kidney or exclusive sarcomatoid carcinoma on needle biopsy) were treated at our institution. We reviewed these patients' records to identify clinical and pathologic features which could affect survival. The role of nephrectomy and systemic therapy on patient outcome was also investigated.

Results: There were 20 male and 10 female patients with a median age of 58 years (range, 43–83). Twenty patients had initially metastatic disease and 16 patients (53%) had ECOG performance status (PS) of 0–1. The most frequent metastatic site was lung (57%) followed by bone (43%) and distant lymph nodes (23%). Fourteen (70%) out of 20 patients with initially metastatic disease underwent primary nephrectomy and six patients also underwent metastasectomy. The median % of sarcomatoid component was 80% (range, 30–100%). All patients (N=10) who received immunotherapy had progressive disease as their best response and only one out of 5 patients treated with sunitinib or everolimus had a partial response. With a median follow-up duration of 22 months, the median survival was 3.6 months (95% CI, 0∼7.5) with 6-month survival rate of 43%. Only ECOG PS had impact on survival (P<0.001: ECOG=0, 14.1 months; ECOG=1, 7.4 months; ECOG=2, 3.2 months, and ECOG=3, 1.64 months). Survivals for initially metastatic disease were not significantly different whether patients underwent nephrectomy or not (2.0 months vs. 3.4 months, HR=0.62, 95% CI, 0.16–2.44 after correcting for potential prognostic factors).

Conclusions: Patients with SRCC have a fulminant clinical course and the majority of patients had disease progression irrespective of any treatment. Only performance status dose have impact on overall survival.

No significant financial relationships to disclose.

Phase II study of a polyethoxylated castor oil–free, polymeric micelle formulation of paclitaxel for patients with advanced urothelial cancer previously treated with gemcitabine and platinum

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Background: Paclitaxel-loaded polymeric micelle (Genexol-PM; G-PM) is a novel polyethoxylated castor oil (Cremophor EL [CrEL])-free formulation of paclitaxel. This multicenter phase II study was designed to evaluate the efficacy and safety of the G-PM monotherapy for the treatment of gemcitabine- and cisplatin-refractory advanced urothelial cancer.

Methods: Patients with advanced urothelial cancer received G-PM 240 mg/m2 intravenously over 3 hours every 3 weeks without premedication as salvage chemotherapy after failure to gemcitabine and cisplatin combination chemotherapy. Intrapatient dose escalation of G-PM to 300 mg/m2 was carried out from the second cycle if the prespecified toxicities were not observed after the first cycle.

Results: Thirty-seven patients were enrolled in this study. Platinum-free interval was less than 6 months in 72% of patients and 64% of patients were categorized into intermediate or poor prognostic group. Overall response rate was 19% including one complete response. When response occurs it is long lasting with a median response duration of 7.8 months (range 1.5∼19.3+). The median progression-free survival was 2.7 months (95% CI, 09-4.6) with a median overall survival of 5.7 months (95% CI, 3.1-8.3). The most common major grade 3-4 non-hematologic toxicity was peripheral neuropathy (sensory type 5.6% and motor type 8.3%) followed by infection (5.6%). Grade 3 or worse hematologic toxicities were observed in only one patient.

Conclusions: G-PM showed modest activity with favorable toxicity profiles when used as salvage therapy after gemcitabine-cisplatin failure in advanced urothelial cancer.

No significant financial relationships to disclose.