Desmoglein 3 promotes cancer cell migration and invasion by regulating activator protein 1 and protein kinase C-dependent-Ezrin activation

Desmoglein 3 (Dsg3), the pemphigus vulgaris antigen, has recently been shown to be upregulated in squamous cell carcinoma (SCC) and has been identified as a good tumor-specific marker for clinical staging of cervical sentinel lymph nodes in head and neck SCC. However, little is known about its biological function in cancer. The actin-binding protein Ezrin and the activator protein 1 (AP-1) transcription factor are implicated in cancer progression and metastasis. Here, we report that Dsg3 regulates the activity of c-Jun/AP-1 as well as protein kinase C (PKC)-mediated phosphorylation of Ezrin-Thr567, which contributes to the accelerated motility of cancer cells. Ectopic expression of Dsg3 in cancer cell lines caused enhanced phosphorylation at Ezrin-Thr567 with concomitant augmented membrane protrusions, cell spreading and invasive phenotype. We showed that Dsg3 formed a complex with Ezrin at the plasma membrane that was required for its proper function of interacting with F-actin and CD44 as Dsg3 knockdown impaired these associations. The increased Ezrin phosphorylation in Dsg3-overexpressing cells could be abrogated substantially by various pharmacological inhibitors for Ser/Thr kinases, including PKC and Rho kinase that are known to activate Ezrin. Furthermore, a marked increase in c-Jun S63 phosphorylation, among others, was found in Dsg3-overexpressing cells and the activation of c-Jun/AP-1 was further supported by a luciferase reporter assay. Taken together, our study identifies a novel Dsg3-mediated c-Jun/AP-1 regulatory mechanism and PKC-dependent Ezrin phosphorylation that could be responsible for Dsg3-associated cancer metastasis.

Use of Cardioselective ß-Blockers in Patients with Chronic Obstructive Pulmonary Disease: A Meta-Analysis of Randomized, Placebo-controlled, Blinded Trials

Objective:

To assess the effect of cardioselective b-blockers on pulmonary function in patients with chronic obstructive pulmonary disease (COPD).

Methods:

The Embase and MEDLINE™ databases and the Cochrane Controlled Trials Register were searched comprehensively to identify all relevant clinical trials in humans published between January 1966 and May 2011. Randomized, blinded, placebo-controlled trials that studied the effects of cardioselective ß-blockers on the forced expiratory volume in 1 s (FEV1) and the responsiveness of the FEV1 to ß-agonist administration in patients with COPD were included in the analysis.

Results:

Five studies were identified: four of these assessed both cardioselective and nonselective ß-blockers; one assessed only cardioselective ß-blockers. The FEV1 was shown to decrease by 0.14 l with nonselective ß-blockers and by 0.03 l with cardioselective ß-blockers. The responsive -ness of the FEV1 to ß-agonist administration decreased significantly by 13.42% after nonselective ß-blockers, but did not change significantly after cardioselective -blocker administration.

Conclusion:

This meta-analysis suggests that the use of β-blockers, especially cardioselective β-blockers, should not be contraindicated in patients with COPD.

Pulmonary benign metastasizing leiomyoma: case report and review of the literature

We present a case of a middle-aged woman who was admitted to the hospital for abdominal pain and was found to have multiple nodules on her CT scan. After CT-guided biopsy, we finally diagnosed PBML case. The patient had a very effective response to bilateral oophorectomy and hysterectomy. A brief review of the literature for PBML is also included.

Circulatory and vascular changes after aneurysmal subarachnoid hemorrhage

Delayed cerebral ischemia (DCI) is a major complication that afflicts approximately 30% of patients who suffer an aneursymal subarachnoid hemorrhage (SAH). DCI is often associated with neurological infarction, poor outcome and mortality. Though the pathogenesis of DCI is not yet clear, it is traditionally been attributed to angiographic vasospasm. Unfortunately, clinical trials based on this premise have mostly been disappointing, predominantly unable to prevent ischemic damage and improve patient outcome despite reducing angiographic vasospasm. More recently, increasing concern that vasospasm could not fully account for DCI development has incited novel proposals as to the pathogenesis of DCI. A general theme exists among these theories (microcirculatory constriction, cortical spreading depression, blood brain barrier breakdown, microthrombosis) in that a majority seems to revolve around dysfunction and changes to the microvasculature. This purpose of this review was then to juxtapose macrovascular and microvascular changes after SAH, and provide an overview of current and prospective treatments.

RNAi-mediated inhibition of the desmosomal cadherin (desmoglein 3) impairs epithelial cell proliferation

OBJECTIVES

  Desmoglein 3 (Dsg3) is a desmosomal adhesion protein expressed in basal and immediate suprabasal layers of skin. Importance of Dsg3 in cell-cell adhesion and maintenance of tissue integrity is illustrated by findings of keratinocyte dissociation in the autoimmune disease, pemphigus vulgaris, where autoantibodies target Dsg3 on keratinocyte surfaces and cause Dsg3 depletion from desmosomes. However, recognition of possible participation of involvement of Dsg3 in cell proliferation remains controversial. Currently, available evidence suggests that Dsg3 may have both anti- and pro-proliferative roles in keratinocytes. The aim of this study was to use RNA interference (RNAi) strategy to investigate effects of silencing Dsg3 in cell-cell adhesion and cell proliferation in two cell lines, HaCaT and MDCK.

MATERIALS AND METHODS

  Cells were transfected with siRNA, and knockdown of Dsg3 was assessed by western blotting, fluorescence-activated cell sorting and confocal microscopy. Cell-cell adhesion was analysed using the hanging drop/fragmentation assay, and cell proliferation by colony forming efficiency, BrdU incorporation, cell counts and organotypic culture.

RESULTS

  Silencing Dsg3 caused defects in cell-cell adhesion and concomitant reduction in cell proliferation in both HaCaT and MDCK cells.

CONCLUSION

  These findings suggest that Dsg3 depletion by RNAi reduces cell proliferation, which is likely to be secondary to a defect in cell-cell adhesion, an essential function required for cell differentiation and morphogenesis.

The I/D polymorphism of angiotensin-converting enzyme gene and asthma risk: a meta-analysis

BACKGROUND

  The insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE) gene has been implicated in susceptibility to asthma, but a large number of studies have reported inconclusive results. The aim of this study is to investigate the association between the I/D polymorphism of ACE gene and asthma risk by meta-analysis.

METHODS

  We searched Medline (Ovid), Pubmed, CNKI, Wanfang, and Weipu database, covering all papers until March 12, 2010. Statistical analysis was performed by using the software revman 4.2 (The Cochrane Collaboration, http://www.cochrane.org) and stata 10.0 (StataCorp, College Station, TX, USA, http://www.stata.com).

RESULTS

  A total of 1946 cases and 2152 controls in 18 case-control studies were included in this meta-analysis. The results indicated that the DD homozygote carriers had a 59% increased risk of asthma, when compared with the homozygotes II and heterozygote DI [odds ratio (OR)=1.59, 95% confidence interval (CI): 1.16-2.18]. In the subgroup analysis by ethnicity, significant elevated risks were associated with DD homozygote carriers in Asians (OR=2.02 and 95% CI: 1.29-3.16 for DD vs DI+II) but not in Caucasians (OR=1.14 and 95% CI: 0.76-1.72 for DD vs DI+II). In the subgroup analysis by age, significant elevated risks were associated with DD homozygote carriers in children (OR=2.44 and 95% CI: 1.36-4.38 for DD vs II+DI) but not in adults (OR=1.54 and 95% CI: 0.94-2.51 for DD vs II+DI).

CONCLUSIONS

  This meta-analysis suggested that the I/D polymorphism of ACE gene would be a risk factor of asthma. To further evaluate gene-to-gene and gene-to-environment interactions between polymorphisms of ACE gene and asthma risk, more studies with large groups of patients are required.

Correlations between clinical and physiological consequences of the novel mutation R878C in a highly conserved pore residue in the cardiac Na+ channel

Aim:

We compared the clinical and physiological consequences of the novel mutation R878C in a highly conserved pore residue in domain II (S5-S6) of human, hNa_v1.5, cardiac Na⁺ channels.

Methods:

Full clinical evaluation of pedigree members through three generations of a Chinese family combined with SCN5A sequencing from genomic DNA was compared with patch and voltage-clamp results from two independent expression systems.

Results:

The four mutation carriers showed bradycardia, and slowed sino-atrial, atrioventricular and intraventricular conduction. Two also showed sick sinus syndrome; two had ST elevation in leads V1 and V2. Unlike WT-hNa_v1.5, whole-cell patch-clamped HEK293 cells expressing R878C-hNa_v1.5 showed no detectable Na⁺ currents (i_Na), even with substitution of a similarly charged lysine residue. Voltage-clamped Xenopus oocytes injected with either 0.04 or 1.5 μg μL⁻¹ R878C-hNa_v1.5 cRNA similarly showed no i_Na, yet WT-hNa_v1.5 cRNA diluted to 0.0004–0.0008 ng μL⁻¹resulted in expression of detectable i_Na. i_Na was simply determined by the amount of injected WT-hNa_v1.5: doubling the dose of WT-hNa_v1.5 cRNA doubled i_Na. i_Na amplitudes and activation and inactivation characteristics were similar irrespective of whether WT-hNa_v1.5 cRNA was given alone or combined with equal doses of R878C-hNa_v1.5 cRNA therefore excluding dominant negative phenotypic effects. Na⁺ channel function in HEK293 cells transfected with R878C-hNa_v1.5 was not restored by exposure to mexiletine (200 μm) and lidocaine (100 μm). Fluorescence confocal microscopy using E3-Nav1.5 antibody demonstrated persistent membrane expression of both WT and R878C-hNa_v1.5. Modelling studies confirmed that such i_Na reductions reproduced the SSS phenotype.

Conclusion:

Clinical consequences of the novel R878C mutation correlate with results of physiological studies.

Group II metabotropic glutamate receptors reduce excitatory but not inhibitory neurotransmission in rat barrel cortex in vivo

Group II metabotropic (mGlu) receptors are known to play an important role in regulating the release of excitatory transmitter in a number of brain areas. Previous experiments demonstrated that (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) depressed excitatory transmission in the adult rat barrel cortex. Here we show, using in vivo extracellular single unit recordings and iontophoretic application of drugs, that selective activation of Group II mGlu receptors depresses excitatory but not inhibitory transmission. The selective Group II receptor agonist (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC) had similar depressant effects to 1S,3R-ACPD on tactile evoked responses of rapidly adapting neurons. The depressant effects were seen on shorter latency (<12 ms) responses, were most pronounced in layers 3-4 (and 5b for 2R,4R-APDC only), and were reversibly antagonized by the Group II receptor antagonist (2S)-alpha-ethylglutamic acid (EGLU) relative to depressions produced by iontophoretic GABA. Where 1S,3R-ACPD and 2R,4R-APDC depressed excitatory transmission, there was little or no effect on postsynaptic excitations produced by iontophoretic AMPA--a result that supports a presynaptic location of Group II receptors on excitatory terminals. To assess the possible involvement of Group II mGlu receptors in the modulation of inhibition, we studied the effect of iontophoretic 1S,3R-ACPD in a condition-test protocol. The results contrasted markedly from those previously observed using the Group III agonist L(+)-2-amino-4-phosphonobutyric acid in that activation of Group II receptors using 1S,3R-ACPD did not modulate inhibition. Therefore our results show that Group II mGlu receptors play an important role in modulating excitatory, but not inhibitory, transmission. We propose that the Group II mGlu receptors are located on excitatory terminals, and act as autoreceptors. Their role appears to be important in the early stages of cortical processing, by keeping excitatory inputs within specified physiological limits, and possibly by mediating depression evidenced during synaptic plasticity.

Multicenter, randomized trial comparing a combined gemcitabine and cisplatin 3-week regimen with a 4-week regimen in non-small cell lung cancer (NSCLC) patients

17062

Background: This multicenter, randomized Phase II study (B9E-GH-JHSE) was aimed to compare the efficacy and safety of a gemcitabine-cisplatin combination over a 3-week schedule versus a 4-week schedule as first line treatment for Chinese patients with advanced NSCLC. Methods: Patients (pts) with pathologically or histologically confirmed stage IIIB/IV NSCLC not amenable to curative surgery, and presenting at least one measurable lesion were eligible for this study. Pts were randomized to receive cisplatin (cis) 75 mg/m2 on Day 1 plus either gemcitabine (gem) 1250 mg/m2 on Day 1 and 8 of a 21-day cycle (3-week arm) or gem 1000 mg/m2 on Day 1, 8, and 15 of a 28-day cycle (4-week arm). Patients received up to 6 cycles of treatment during this study. The primary endpoint was WHO objective response rate (ORR) and secondary endpoints included time to progression (TTP), CTC toxicity, and overall survival. Results: Of the 100 pts who were randomized to treatment, there were 51 pts in the 3-week arm: 14 females; mean age 59±8 yrs; 37% stage IIIB, 63% stage IV. In the 4-week arm, there were 49 pts: 24 females; mean age 56 ± 13 yrs; 33% stage IIIB, 67% stage IV. In the 3-week arm the overall response rate (complete response or partial response) was 24%, compared to 27% in the 4-week arm (Odds ratio: 1.17, 95% CI 0.47– 2.9, p = .819). There were no statistically significant differences between the two treatment arms in median overall survival time (3-week: 12.1 mths, 4-week: 13.8 mths; Hazard ratio (HR): 1.19, 95% CI 0.68–2.1, p = .54) and TTP (3-week: 4.9 mths, 4-week: 6.9 mths; HR: 1.33, 95% CI 0.85–2.1, p = .21). The difference in grade 3/4 hematological toxicities did not reach statistical significance (3-week: 37%, 4-week: 57%, p = .07), while grade 3/4 non-hematological toxicities were statistically significantly reduced in the 3-week arm (33% vs. 63%, p = .005). Grade 3/4 study drug related neutropenia (3-week: 27%, 4-week: 51%, p = .02) and thrombocytopenia (3-week: 8%, 4-week: 31%, p = .005) were reduced in the 3-week arm. Conclusions: While all efficacy endpoints were numerically superior in the 4-week arm, the difference was not statistically significant. However, grade 3/4 toxicities were reduced in the 3-week arm.

[Table: see text]

Angiogenic murine endothelial progenitor cells are derived from a myeloid bone marrow fraction and can be identified by endothelial NO synthase expression

OBJECTIVE

Endothelial progenitor cells (EPCs) contribute to postnatal neovascularization and are therefore of great interest for autologous cell therapies to treat ischemic vascular disease. However, the origin and functional properties of these EPCs are still in debate.

METHODS AND RESULTS

Here, ex vivo expanded murine EPCs were characterized in terms of phenotype, lineage potential, differentiation from bone marrow (BM) precursors, and their functional properties using endothelial NO synthase (eNOS)-green fluorescent protein transgenic mice. Despite high phenotypic overlap with macrophages and dendritic cells, EPCs displayed unique eNOS expression, endothelial lineage potential in colony assays, and angiogenic characteristics, but also immunologic properties such as interleukin-12p70 production and low levels of T-cell stimulation. The majority of EPCs developed from an immature, CD31(+)Ly6C+ myeloid progenitor fraction in the BM. Addition of myeloid growth factors such as macrophage-colony-stimulating factor (M-CSF) and granulocyte/macrophage (GM)-CSF stimulated the expansion of spleen-derived EPCs but not BM-derived EPCs.

CONCLUSIONS

The close relationship between EPCs and other myeloid lineages may add to the complexity of using them in cell therapy. Our mouse model could be a highly useful tool to characterize EPCs functionally and phenotypically, to explore the origin and optimize the isolation of EPC fractions for therapeutic neovascularization.

Effect of carbon dioxide injection on production of wood cement composites from waste medium density fiberboard (MDF)

The possibility of recycling waste medium density fiberboard (MDF) into wood-cement composites was evaluated. Both new fibers and recycled steam exploded MDF fibers had poor compatibility with cement if no treatment was applied, due to interference of the hydration process by the water soluble components of the fiber. However, this issue was resolved when a rapid hardening process with carbon dioxide injection was adopted. It appears that the rapid carbonation allowed the board to develop considerable strength before the adverse effects of the wood extractives could take effect. After 3-5 min of carbon dioxide injection, the composites reached 22-27% of total carbonation and developed 50-70% of their final (28-day) strength. Composites containing recycled MDF fibers had slightly lower splitting tensile strength and lower tensile toughness properties than those containing new fibers especially at a high fiber/cement ratio. Composites containing recycled MDF fibers also showed lower values of water absorption. Unlike composites cured conventionally, composites cured under CO(2) injection developed higher strength and toughness with increased fiber content. Incorporation of recycled MDF fibers into wood cement composites with CO(2) injection during the production stage presents a viable option for recycling of this difficult to manage waste material.

Investigating the binding interaction of azur A with hyaluronic acid via spectrophotometry and its analytical application

The interaction between azur A (AA) and hyaluronic acid (HA) at AA concentrations from 3.430 x 10(-5) to 8.575 x 10(-5) M and sodium chloride concentrations from 0 to 0.01 M was investigated spectrophotometrically at 620 nm at temperatures from 0 to 50 degrees C. AA was shown to be a useful spectroscopic probe for detecting carboxyl groups in HA macromolecules. The interaction between AA and HA was temperature sensitive and little AA-HA interaction was observed at temperatures higher than 30 degrees C. The interaction of HA with AA was seen to be electrostatic in nature. The maximum binding number decreased with decreasing NaCl concentration, and the absorbance sensitivity decreased with increasing NaCl concentration in aqueous solution. Self-interference from the AA in the AA-HA interaction caused an overestimate of the molar mass of hyaluronic acid. An improved method was proposed to estimate the molar mass of HA, and a molar mass of 1.219 x 10(6) Da was obtained with this improved method for HA.