C2ORF40 suppresses breast cancer cell proliferation and invasion through modulating expression of M phase cell cycle genes

Recently, it has been suggested that C2ORF40 is a candidate tumor suppressor gene in breast cancer. However, the mechanism for reduced expression of C2ORF40 and its functional role in breast cancers remain unclear. Here we show that C2ORF40 is frequently silenced in human primary breast cancers and cell lines through promoter hypermethylation. C2ORF40 mRNA level is significantly associated with patient disease-free survival and distant cancer metastasis. Overexpression of C2ORF40 inhibits breast cancer cell proliferation, migration and invasion. By contrast, silencing C2ORF40 expression promotes these biological phenotypes. Bioinformatics and FACS analysis reveal C2ORF40 functions at G2/M phase by downregulation of mitotic genes expression, including UBE2C. Our results suggest that C2ORF40 acts as a tumor suppressor gene in breast cancer pathogenesis and progression and is a candidate prognostic marker for this disease.     

Impact of Obstructive Sleep Apnea on the Levels of Placental Growth Factor (PlGF) and Their Value for Predicting Short-Term Adverse Outcomes in Patients with Acute Coronary Syndrome

Background

Placental growth factor (PlGF) induces angiogenesis and promotes tissue repair, and plasma PlGF levels change markedly during acute myocardial infarction (AMI). Currently, the impact of obstructive sleep apnea (OSA) in patients with AMI is a subject of debate. Our objective was to evaluate the relationships between PlGF levels and both the severity of acute coronary syndrome (ACS) and short-term outcomes after ACS in patients with and without OSA.

Methods

A total of 538 consecutive patients (312 OSA patients and 226 controls) admitted for ACS were included in this study. All patients underwent polygraphy in the first 72 hours after hospital admission. The severity of disease and short-term prognoses were evaluated during the hospitalization period. Plasma PlGF levels were measured using an electrochemiluminescence immunoassay.

Results

Patients with OSA were significantly older and more frequently hypertensive and had higher BMIs than those without OSA. After adjusting for age, smoking status, BMI and hypertension, PlGF levels were significantly elevated in patients with OSA compared with patients without OSA (19.9 pg/mL, interquartile range: 16.6–24.5 pg/mL; 18.5 pg/mL, interquartile range: 14.7–22.7 pg/mL; p<0.001), and a higher apnea-hypopnea index (AHI) was associated with higher PlGF concentrations (p<0.003). Patients with higher levels of PlGF had also an increased odds ratio for the presence of 3 or more diseased vessels and for a Killip score>1, even after adjustment.

Conclusions

The results of this study show that in patients with ACS, elevated plasma levels of PlGF are associated with the presence of OSA and with adverse outcomes during short-term follow-up.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01335087","term_id":"NCT01335087"}}NCT01335087     

Guideline Adherence in Outpatient Clinics for Chronic Obstructive Pulmonary Disease: Results from a Clinical Audit

Objectives

Previous clinical audits of COPD have provided relevant information about medical intervention in exacerbation admissions. The present study aims to evaluate adherence to current guidelines in COPD through a clinical audit.

Methods

This is a pilot clinical audit performed in hospital outpatient respiratory clinics in Andalusia, Spain (eight provinces with more than 8 million inhabitants), including 9 centers (20% of the public centers in the area) between 2013 and 2014. Cases with an established diagnosis of COPD based on risk factors, clinical symptoms, and a post-bronchodilator FEV₁/FVC ratio of less than 0.70 were deemed eligible. The performance of the outpatient clinics was benchmarked against three guidance documents available at the time of the audit. The appropriateness of the performance was categorized as excellent (>80%), good (60−80%), adequate (40−59%), inadequate (20−39%), and highly inadequate (<20%).

Results

During the audit, 621 clinical records were audited. Adherence to the different guidelines presented a considerable variability among the different participating hospitals, with an excellent or good adherence for symptom recording, MRC or CAT use, smoking status evaluation, spirometry, or bronchodilation therapy. The most outstanding areas for improvement were the use of the BODE index, the monitoring of treatments, the determination of alpha1-antitrypsin, the performance of exercise testing, and vaccination recommendations.

Conclusions

The present study reflects the situation of clinical care for COPD patients in specialized secondary care outpatient clinics. Adherence to clinical guidelines shows considerable variability in outpatient clinics managing COPD patients, and some aspects of the clinical care can clearly be improved.     

A CRISPR-Cas9 screen reveals a role for WD repeat-containing protein 81 (WDR81) in the entry of late penetrating viruses

Successful initiation of infection by many different viruses requires their uptake into the endosomal compartment. While some viruses exit this compartment early, others must reach the degradative, acidic environment of the late endosome. Mammalian orthoreovirus (reovirus) is one such late penetrating virus. To identify host factors that are important for reovirus infection, we performed a CRISPR-Cas9 knockout (KO) screen that targets over 20,000 genes in fibroblasts derived from the embryos of C57/BL6 mice. We identified seven genes (WDR81, WDR91, RAB7, CCZ1, CTSL, GNPTAB, and SLC35A1) that were required for the induction of cell death by reovirus. Notably, CRISPR-mediated KO of WD repeat-containing protein 81 (WDR81) rendered cells resistant to reovirus infection. Susceptibility to reovirus infection was restored by complementing KO cells with human WDR81. Although the absence of WDR81 did not affect viral attachment efficiency or uptake into the endosomal compartments for initial disassembly, it reduced viral gene expression and diminished infectious virus production. Consistent with the role of WDR81 in impacting the maturation of endosomes, WDR81-deficiency led to the accumulation of reovirus particles in dead-end compartments. Though WDR81 was dispensable for infection by VSV (vesicular stomatitis virus), which exits the endosomal system at an early stage, it was required for VSV-EBO GP (VSV that expresses the Ebolavirus glycoprotein), which must reach the late endosome to initiate infection. These results reveal a previously unappreciated role for WDR81 in promoting the replication of viruses that transit through late endosomes.     

The lipid charge density at the bilayer surface modulates the effects of melittin on membranes

The influence of melittin on two DMPA membrane systems at pH 4.2 and 8.2 has been investigated by solid-state 31P and 2H NMR, as a function of temperature and peptide concentration. Melittin promotes greater morphological changes for both systems in the fluid phase, the effect being larger at pH 4.2. Close inspection of fatty acyl chain dynamics suggests that some parallels can be drawn between the DMPA/melittin at pH 8.2 and PC/melittin systems. In addition, at pH 8.2 a direct neutralization at the interface of one of the lipid negative charges by a positive charge of the peptide occurs, as can be monitored by 31P NMR at the molecular level. For the system at pH 4.2 and at high temperature, a lipid-to-peptide molar ratio of 30 is sufficient to transform the whole system into an isotropic phase, proposed to be inverted micelles. When the system is cooled down towards the gel phase one observes an intermediate hexagonal phase in a narrow range of temperature.     

The analysis of Circe, an LTR retrotransposon of Drosophila melanogaster, suggests that an insertion of non-LTR retrotransposons into LTR elements can create chimeric retroelements

Circe is a transposable element recently identified in Drosophila melanogaster which appears to be mostly associated with the constitutive heterochromatin. This element shows the structural features of a long terminal repeat (LTR)-containing retrotransposon: It is flanked by 240-bp-long terminal repeats, and its two open reading frames encode putative proteins resembling the gag and pol polyproteins of retroviruses. However, Circe displays striking similarities of both LOA and Ulysses, a non-LTR element and an LTR element, respectively. The result of its phylogenetic and structural analysis has allowed us to propose a new mechanism for non-LTR retrotransposon evolution.     

Dynamic light scattering studies of irradiated kappa carrageenan

Investigation of the dynamic behavior of irradiated kappa carrageenan (in KCl) as a function of irradiation dose and temperature was done by dynamic light scattering (DLS). The intensity correlation function (ICF) shifted towards shorter relaxation times with increasing radiation dose as a result of radiolysis. The characteristic decay time distribution function, G(gamma), indicates the presence of fast and slow mode peaks respectively at around 0.1-10 ms and 100-1000 ms. A peak broadening of the fast mode peak in G(gamma) appeared with decreasing temperature, indicating that coil-to-helical conformational transition took place. The conformation transition temperature (CTT) decreased with increasing radiation dose. No transition was observed for kappa-carrageenan irradiated at 200 kGy. A new faster relaxation mode appeared at around 0.1-1 ms at temperatures below the CTT. This peak is found in kappa-carrageenan irradiated at doses exclusively between 75 and 175 kGy. The peak height of this mode is largest at 100 kGy which corresponds to the optimum biologic activity of kappa-carrageenan reported previously.     

Synthesis and cytotoxicity of hydrophobic esters of podophyllotoxins

Diverse norbornenecarboxylate esters of podophyllotoxin and its epimers and diastereoisomers have been prepared through Diels-Alder cycloaddition by treating the dienophilic acrylates of cyclolignans with cyclopentadiene. Their cytotoxicities against several cancer cell lines have been evaluated and the results compared with those found for other lignan esters. Podophyllotoxin adducts showed a one-fold increase in activity when compared to the natural product. The preparation of more hydrophobic esters, which showed less cytotoxicity, demonstrated that this activity is not primarily due to the lipophilic factor, but mainly to the spatial arrangement of the bulky moiety, which could contribute to increase the binding to the target site.     

Arabidopsis formin AtFH6 is a plasma membrane-associated protein upregulated in giant cells induced by parasitic nematodes

Plant-parasitic nematodes Meloidogyne spp induce an elaborate permanent feeding site characterized by the redifferentiation of root cells into multinucleate and hypertrophied giant cells. We have isolated by a promoter trap strategy an Arabidopsis thaliana formin gene, AtFH6, which is upregulated during giant cell formation. Formins are actin-nucleating proteins that stimulate de novo polymerization of actin filaments. We show here that three type-I formins were upregulated in giant cells and that the AtFH6 protein was anchored to the plasma membrane and uniformly distributed. Suppression of the budding defect of the Saccharomyces cerevisiae bni1Delta bnr1Delta mutant showed that AtFH6 regulates polarized growth by controlling the assembly of actin cables. Our results suggest that AtFH6 might be involved in the isotropic growth of hypertrophied feeding cells via the reorganization of the actin cytoskeleton. The actin cables would serve as tracks for vesicle trafficking needed for extensive plasma membrane and cell wall biogenesis. Therefore, determining how plant parasitic nematodes modify root cells into giant cells represents an attractive system to identify genes that regulate cell growth and morphogenesis.