GJB5 association with BRAF mutation and survival in cutaneous malignant melanoma.

BACKGROUND: Gap-junctional intercellular communication is crucial for epidermal cellular homeostasis. Inability to establish melanocyte-keratinocyte contact and loss of the intercellular junction's integrity may contribute to melanoma development. Connexins, laminins and desmocollins have been implicated in the control of melanoma growth, where their reduced expression has been reported in metastatic lesions. OBJECTIVES: The aim of this study was to investigate connexin 31·1 (GJB5) expression and identify any association with BRAF mutational status, prognosis of patients with melanoma and mitogen-activated protein kinase (MAPK) inhibitor (MAPKi) treatment. METHODS: GJB5 expression was measured at RNA and protein level in melanoma clinical samples and established cell lines treated (or not) with BRAF and MEK inhibitors (MEKi), as well as in cell lines which developed MAPKi resistance. Findings were further validated and confirmed by analysis of independent datasets. RESULTS: Our analysis reveals significant downregulation of GJB5 expression in metastatic melanoma lesions compared with primary ones and in BRAF-mutated vs. BRAF-wildtype (BRAFWT ) melanomas. Likewise, GJB5 expression is significantly lower in BRAFV600E compared with BRAFWT cell lines and increases on MAPKi treatment. MAPKi-resistant melanoma cells display a similar expression pattern compared with BRAFWT cells, with increased GJB5 expression associated with morphological changes. Enhancement of BRAFV600E expression in BRAFWT melanoma cells significantly upregulates miR-335-5p expression with consequent downregulation of GJB5, one of its targets. Furthermore, overexpression of miR-335-5p in two BRAFWT cell lines confirms specific GJB5 protein downregulation. Reverse transcriptase quantitative polymerase chain reaction analysis also revealed upregulation of miR-335 in BRAFV600E melanoma cells, which is significantly downregulated in cells resistant to MEKi. Our data were further validated using the TCGA_SKCM dataset, where BRAF mutations associate with increased miR-335 expression and inversely correlate with GJB5 expression. In clinical samples, GJB5 underexpression is also associated with patient overall worse survival, especially at early stages. CONCLUSIONS: We identified a significant association between metastases/BRAF mutation and low GJB5 expression in melanoma. Our results identify a novel mechanism of gap-junctional protein regulation, suggesting a prognostic role for GJB5 in cutaneous melanoma.

Calculadoras de riesgo cardiovascular en personas viviendo con el virus de la inmunodeficiencia humana / Cardiovascular risk calculators for people living with human immunodeficiency virus

El creciente acceso y la alta eficacia del tratamiento antirretroviral han permitido que las personas que viven con el virus de la inmunodeficiencia humana alcancen una expectativa de vida semejante a la población general. Sin embargo, esta expectativa puede verse afectada por el aumento del riesgo de enfermedad cardiovascular en estos pacientes. Este riesgo es multifactorial, involucrando la elevada prevalencia de factores de riesgo cardiovascular tradicionales, el desarrollo de un estado proinflamatorio relacionado con la infección crónica y el uso de fármacos antirretrovirales con un perfil metabólico adverso. En la práctica clínica diaria disponemos de diferentes tablas y/o calculadoras para estimar el riesgo cardiovascular y orientar en la toma de decisiones médicas. La mayoría de estos surgen de estudios poblacionales en pacientes sin infección por el virus de la inmunodeficiencia humana. El objetivo de esta revisión es describir algunos determinantes de la enfermedad cardiovascular en personas que viven con el virus de la inmunodeficiencia humana, y la utilidad y aplicación de las calculadoras de riesgo cardiovascular en dichas personas

The increasing access and efficacy of antiretroviral therapy has allowed people living with human immunodeficiency virus to achieve a life expectancy similar to that of the general population. However, this goal may be affected by the increased risk of cardiovascular disease in this group. This risk is multifactorial, involving the high prevalence of traditional risk factors, the development of a pro-inflammatory state related to chronic infection, and the use of antiretroviral drugs with an adverse metabolic profile. In daily practice, in order to estimate this risk and guide medical decision-making, different calculators are available. These are based on data from population cohorts, many of them from human immunodeficiency virusnegative subjects. The main aim of this review is to describe the epidemiology of cardiovascular disease in people living with human immunodeficiency virus, the available risk calculators and their use

Lesion evolution and neurodegeneration in RVCL-S: A monogenic microvasculopathy.

OBJECTIVE: To characterize lesion evolution and neurodegeneration in retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) using multimodal MRI. METHODS: We prospectively performed MRI and cognitive testing in RVCL-S and healthy control cohorts. Gray and white matter volume and disruption of white matter microstructure were quantified. Asymmetric spin echo acquisition permitted voxel-wise oxygen extraction fraction (OEF) calculation as an in vivo marker of microvascular ischemia. The RVCL-S cohort was included in a longitudinal analysis of lesion subtypes in which hyperintense lesions on fluid-attenuated inversion recovery (FLAIR), T1-postgadolinium, and diffusion-weighted imaging were delineated and quantified volumetrically. RESULTS: Twenty individuals with RVCL-S and 26 controls were enrolled. White matter volume and microstructure declined faster in those with RVCL-S compared to controls. White matter atrophy in RVCL-S was highly linear (ρ = -0.908, p < 0.0001). Normalized OEF was elevated in RVCL-S and increased with disease duration. Multiple cognitive domains, specifically those measuring working memory and processing speed, were impaired in RVCL-S. Lesion volumes, regardless of subtype, progressed/regressed with high variability as a function of age, while FLAIR lesion burden increased near time to death (p < 0.001). CONCLUSION: RVCL-S is a monogenic microvasculopathy affecting predominantly the white matter with regard to atrophy and cognitive impairment. White matter volumes in RVCL-S declined linearly, providing a potential metric against which to test the efficacy of future therapies. Progressive elevation of white matter OEF suggests that microvascular ischemia may underlie neurodegeneration in RVCL-S.

[Cardiovascular risk calculators for people living with human immunodeficiency virus]. / Calculadoras de riesgo cardiovascular en personas viviendo con el virus de la inmunodeficiencia humana.

The increasing access and efficacy of antiretroviral therapy has allowed people living with human immunodeficiency virus to achieve a life expectancy similar to that of the general population. However, this goal may be affected by the increased risk of cardiovascular disease in this group. This risk is multifactorial, involving the high prevalence of traditional risk factors, the development of a pro-inflammatory state related to chronic infection, and the use of antiretroviral drugs with an adverse metabolic profile. In daily practice, in order to estimate this risk and guide medical decision-making, different calculators are available. These are based on data from population cohorts, many of them from human immunodeficiency virusnegative subjects. The main aim of this review is to describe the epidemiology of cardiovascular disease in people living with human immunodeficiency virus, the available risk calculators and their use.

Sources of elevated heavy metal concentrations in sediments and benthic marine invertebrates of the western Antarctic Peninsula.

Antarctica is one of the least anthropogenically-impacted areas of the world. Metal sources to the marine environment include localised activities of research stations and glacial meltwater containing metals of lithogenic origin. In this study, concentrations of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were examined in three species of benthic invertebrates collected from four locations near Rothera Research Station on the western Antarctic Peninsula: Laternula elliptica (mudclam, filter feeder), Nacella concinna (limpet, grazer) and Odontaster validus (seastar, predator and scavenger). In addition, metals were evaluated in sediments at the same locations. Metal concentrations in different body tissues of invertebrates were equivalent to values recorded in industrialized non-polar sites and were attributed to natural sources including sediment input resulting from glacial erosion of local granodioritic rocks. Anthropogenic activities at Rothera Research Station appeared to have some impact on metal concentrations in the sampled invertebrates, with concentrations of several metals higher in L. elliptica near the runway and aircraft activities, but this was not a trend that was detected in the other species. Sediment analysis from two sites near the station showed lower metal concentrations than the control site 5 km distant and was attributed to differences in bedrock metal content. Differences in metal concentrations between organisms were attributed to feeding mechanisms and habitat, as well as depuration routes. L. elliptica kidneys showed significantly higher concentrations of eight metals, with some an order of magnitude greater than other organs, and the internal structure of O. validus had significantly higher Ni. This study supports previous assessments of N. concinna and L. elliptica as good biomonitors of metal concentrations and suggests O. validus as an additional biomonitor for use in future Antarctic metal monitoring programs.

Early alterations in a mouse model of Rett syndrome: the GABA developmental shift is abolished at birth.

Genetic mutations of the Methyl-CpG-binding protein-2 (MECP2) gene underlie Rett syndrome (RTT). Developmental processes are often considered to be irrelevant in RTT pathogenesis but neuronal activity at birth has not been recorded. We report that the GABA developmental shift at birth is abolished in CA3 pyramidal neurons of Mecp2-/y mice and the glutamatergic/GABAergic postsynaptic currents (PSCs) ratio is increased. Two weeks later, GABA exerts strong excitatory actions, the glutamatergic/GABAergic PSCs ratio is enhanced, hyper-synchronized activity is present and metabotropic long-term depression (LTD) is impacted. One day before delivery, maternal administration of the NKCC1 chloride importer antagonist bumetanide restored these parameters but not respiratory or weight deficits, nor the onset of mortality. Results suggest that birth is a critical period in RTT with important alterations that can be attenuated by bumetanide raising the possibility of early treatment of the disorder.

GABAergic inhibition in dual-transmission cholinergic and GABAergic striatal interneurons is abolished in Parkinson disease.

We report that half striatal cholinergic interneurons are dual transmitter cholinergic and GABAergic interneurons (CGINs) expressing ChAT, GAD65, Lhx7, and Lhx6 mRNAs, labeled with GAD and VGAT, generating monosynaptic dual cholinergic/GABAergic currents and an inhibitory pause response. Dopamine deprivation increases CGINs ongoing activity and abolishes GABAergic inhibition including the cortico-striatal pause because of high [Cl-]i levels. Dopamine deprivation also dramatically increases CGINs dendritic arbors and monosynaptic interconnections probability, suggesting the formation of a dense CGINs network. The NKCC1 chloride importer antagonist bumetanide, which reduces [Cl-]i levels, restores GABAergic inhibition, the cortico-striatal pause-rebound response, and attenuates motor effects of dopamine deprivation. Therefore, most of the striatal cholinergic excitatory drive is balanced by a concomitant powerful GABAergic inhibition that is impaired by dopamine deprivation. The attenuation by bumetanide of cardinal features of Parkinson's disease paves the way to a novel therapeutic strategy based on a restoration of low [Cl-]i levels and GABAergic inhibition.

Olesoxime favors oligodendrocyte differentiation through a functional interplay between mitochondria and microtubules.

Multiple sclerosis (MS) is a neurodegenerative disease characterized by episodes of immune attacks and oligodendrocyte death leading to demyelination and progressive functional deficits. New therapeutic strategies are needed to stimulate the spontaneous regenerative process observed in some patients. Spontaneous myelin repair relies on the mobilization and differentiation of endogenous oligodendrocyte progenitors at the lesion site. Olesoxime, a cholesterol-like compound, has been shown to favor oligodendrocyte maturation in culture and promote myelin regeneration in rodents. Here, we study the mode of action of this compound and show that it binds to oligodendrocyte mitochondria, leading to their hyperfilamentation. This is accompanied by a reduction of basal superoxide levels, and accumulation of End Binding Protein 1 (EB1) at growing ends of microtubules. In parallel, we demonstrate that Reactive Oxygen Species (ROS) scavengers also promote oligodendrocyte differentiation, together with increasing mitochondrial filamentation and EB1-dependent microtubule polymerization. Altogether, our data uncover the mechanisms by which olesoxime promotes oligodendrocyte maturation. They also reveal that a bidirectional relationship between mitochondria hyperfilamentation and ROS level modulation controls oligodendrocyte maturation. This study identifies new cellular mechanisms to target for the development of regenerative treatments for MS.

HEMORRHAGIC RISK OF VITREORETINAL SURGERY IN PATIENTS MAINTAINED ON NOVEL ORAL ANTICOAGULANT THERAPY.

PURPOSE: To evaluate the frequency and type of perioperative hemorrhagic complications associated with vitreoretinal surgery in patients undergoing systemic treatment with the newer anticoagulant and antiplatelet agents including rivaroxaban, apixaban, dabigatran, and prasugrel. METHODS: Retrospective review of a cohort of patients being treated with anticoagulant and antiplatelet drugs, who underwent any vitreoretinal surgical procedure over a 2-year period. RESULTS: Thirty-six eyes of 33 patients were identified who underwent vitreoretinal surgical operations while being treated systemically with anticoagulant and antiplatelet therapy. No eyes suffered perioperative complications of retrobulbar hemorrhage, suprachoroidal hemorrhage, or subretinal hemorrhage. Four eyes (11.1%) experienced postoperative vitreous cavity hemorrhage after which two eyes (5.5%) required repeat surgical intervention and two eyes (5.5%) cleared spontaneously. CONCLUSION: Although there is a relative risk to such surgery in patients who are taking novel oral anticoagulants, these findings suggest that patients may safely undergo vitreoretinal surgery while maintaining therapy with rivaroxaban, apixaban, dabigatran, and prasugrel.

Dynamic prediction in breast cancer: proving feasibility in clinical practice using the TEAM trial.

BACKGROUND: Predictive models are an integral part of current clinical practice and help determine optimal treatment strategies for individual patients. A drawback is that covariates are assumed to have constant effects on overall survival (OS), when in fact, these effects may change during follow-up (FU). Furthermore, breast cancer (BC) patients may experience events that alter their prognosis from that time onwards. We investigated the 'dynamic' effects of different covariates on OS and developed a nomogram to calculate 5-year dynamic OS (DOS) probability at different prediction timepoints (tP) during FU. METHODS: Dutch and Belgian postmenopausal, endocrine-sensitive, early BC patients enrolled in the TEAM trial were included. We assessed time-varying effects of specific covariates and obtained 5-year DOS predictions using a proportional baselines landmark supermodel. Covariates included age, histological grade, hormone receptor and HER2 status, T- and N-stage, locoregional recurrence (LRR), distant recurrence, and treatment compliance. A nomogram was designed to calculate 5-year DOS based on individual characteristics. RESULTS: A total of 2602 patients were included (mean FU 6.2 years). N-stage, LRR, and HER2 status demonstrated time-varying effects on 5-year DOS. Hazard ratio (HR) functions for LRR, high-risk N-stage (N2/3), and HER2 positivity were HR = (8.427 × 0.583[Formula: see text], HR = (3.621 × 0.816[Formula: see text], and HR = (1.235 × 0.851[Formula: see text], respectively. Treatment discontinuation was associated with a higher mortality risk, but without a time-varying effect [HR 1.263 (0.867-1.841)]. All other covariates were time-constant. DISCUSSION: The current nomogram accounts for elapsed time since starting adjuvant endocrine treatment and optimizes prediction of individual 5-year DOS during FU for postmenopausal, endocrine-sensitive BC patients. The nomogram can facilitate in determining whether further therapy will benefit an individual patient, although validation in an independent dataset is still needed.

Aberrant expression of the neuronal-specific protein DCDC2 promotes malignant phenotypes and is associated with prostate cancer progression.

By integrating gene profiling and immunohistochemical data with functional experiments in cell lines in this study we show for the first time that doublecortin (DCX) domain containing 2 (DCDC2), a protein belonging to the DCX family and involved in neuronal cell migration, is aberrantly expressed in prostate tumors whereas absent in normal prostate. Furthermore, in patients treated with radical prostatectomy, high levels of DCDC2 RNA were significantly associated with increased biochemical relapse (LogRank Mantel-Cox=0.012). Mechanistically, we found that the ETS transcription factor ESE3/EHF, which is expressed in normal prostate and frequently lost in prostate tumors, maintained DCDC2 repressed by binding to a novel identified ETS binding site in the gene promoter. Consistently, in prostate tumors and in cellular models of gain and loss of ESE3/EHF, the expression of DCDC2 and ESE3/EHF were inversely correlated. In prostate cancer cells, DCDC2 colocalized with microtubules and promoted cell migration and resistance to the microtubule-targeting drug taxol. Collectively, this study establishes DCDC2 as a novel ESE3/EHF oncogenic target in prostate cancer. These findings may be relevant for the clinical management of prostate cancer as DCDC2 may signal tumors more prone to relapse and resistant to taxol treatment.

The SRA protein UHRF1 promotes epigenetic crosstalks and is involved in prostate cancer progression.

Epigenetic silencing of tumour suppressor genes is an important mechanism involved in cell transformation and tumour progression. The Set and RING-finger-associated domain-containing protein UHRF1 might be an important link between different epigenetic pathways. Here, we report that UHRF1 is frequently overexpressed in human prostate tumours and has an important role in prostate cancer pathogenesis and progression. Analysis of human prostate cancer samples by microarrays and immunohistochemistry showed increased expression of UHRF1 in about half of the cases. Moreover, UHRF1 expression was associated with reduced overall survival after prostatectomy in patients with organ-confined prostate tumours (P < 0.0001). UHRF1 expression was negatively correlated with several tumour suppressor genes and positively with the histone methyltransferase (HMT) EZH2 both in prostate tumours and cell lines. UHRF1 knockdown reduced proliferation, clonogenic capability and anchorage-independent growth of prostate cancer cells. Depletion of UHRF1 resulted in reactivation of several tumour suppressor genes. Gene reactivation upon UHRF1 depletion was associated with changes in histone H3K9 methylation, acetylation and DNA methylation, and impaired binding of the H3K9 HMT Suv39H1 to the promoter of silenced genes. Co-immunoprecipitation experiments showed direct interaction between UHRF1 and Suv39H1. Our data support the notion that UHRF1, along with Suv39H1 and DNA methyltransferases, contributes to epigenetic gene silencing in prostate tumours. This could represent a parallel and convergent pathway to the H3K27 methylation catalyzed by EZH2 to synergistically promote inactivation of tumour suppressor genes. Deregulated expression of UHRF1 is involved in the prostate cancer pathogenesis and might represent a useful marker to distinguish indolent cancer from those at high risk of lethal progression.

Pars plana vitrectomy versus combined pars plana vitrectomy and scleral buckle for primary repair of rhegmatogenous retinal detachment.

OBJECTIVE: To compare pars plana vitrectomy (PPV) with PPV and scleral buckle (PPV/SB) for repair of rhegmatogenous retinal detachment (RRD). DESIGN: A retrospective chart review. PARTICIPANTS: Patients who underwent PPV or PPV/SB for RRD repair at a single institution. METHODS: A retrospective chart review of patients in two different treatment groups and analysis of the anatomic and functional results. RESULTS: Single-surgery anatomic success was achieved in 31 of 37 (83.8%) phakic eyes that underwent PPV and in 66 of 68 (97.1%) phakic eyes that underwent PPV/SB (p = 0.0216). Among pseudophakic eyes, 42 of 48 (87.5%) in the PPV group and 62 of 66 (93.9%) in the PPV/SB group achieved single-surgery reattachment (p = 0.3175). Visual acuity improvement was marginally greater in the PPV group among phakic (p = 0.4898) and pseudophakic (p = 0.2465) eyes. CONCLUSIONS: PPV/SB may be associated with a decreased risk for retinal redetachment when compared to PPV for repair of phakic RRD. In pseudophakic eyes, the anatomic success rate between the two techniques appears to be similar.

Intravitreal bevacizumab for the treatment of refractory diabetic macular edema.

BACKGROUND AND OBJECTIVE: To report the effect of intravitreal bevacizumab on visual acuity and central retinal thickness (CRT) in refractory diabetic macular edema. PATIENTS AND METHODS: Records of 60 eyes of 54 consecutive patients who underwent intravitreal bevacizumab therapy for refractory diabetic macular edema were reviewed. All eyes received intravitreal bevacizumab 1.25 mg/0.05 mL, and 36 eyes underwent pretreatment and post-treatment optical coherence tomography. Mean follow-up was 7.4 months. RESULTS: Pretreatment mean visual acuity plus or minus standard deviation was 0.71 +/- 0.28 logarithm of the minimum angle of resolution (LogMAR) Snellen letters. At final follow-up, mean visual acuity had improved to 0.66 +/- 0.30 LogMAR (P = .0543). Mean baseline CRT was 440 +/- 106 microm, and follow-up mean CRT was 386 +/- 129 microm (P = .008). Vitrectomized eyes had worse visual acuity and CRT outcomes (P = .002 and P = .028, respectively) compared with nonvitrectomized eyes. CONCLUSION: Intravitreal bevacizumab may provide a functional and anatomic benefit in eyes with persistent diabetic macular edema despite previous treatments.

Dexrazoxane protects the heart from acute doxorubicin-induced QT prolongation: a key role for I(Ks).

INTRODUCTION: Doxorubicin, an anthracycline widely used in the treatment of a broad range of tumours, causes acute QT prolongation. Dexrazoxane has been shown to prevent the QT prolongation induced by another anthracycline, epirubicin, but has not yet been reported to prevent that induced by doxorubicin. Thus, the present study was designed to test whether the acute QT effects induced by doxorubicin could be blocked by dexrazoxane and to explore the mechanism. Results were compared with those obtained with a reference human ether-a-go-go (hERG) channel blocker, moxifloxacin. METHODS: The effects of moxifloxacin (100 microM) and doxorubicin (30 microM), with or without dexrazoxane (from 3 to 30 microM), have been evaluated on the QTc interval in guinea-pig isolated hearts and on I(Kr) (rapid component of the delayed rectifier current) and I(Ks) (slow component of the delayed rectifier current) currents stably expressed in human embryonic kidney 293 cells. RESULTS: Moxifloxacin (100 microM), a potent hERG blocker, prolonged QTc by 22%, and this effect was not prevented by dexrazoxane. Doxorubicin (30 microM) also prolonged QTc by 13%, did not significantly block hERG channels and specifically inhibited I(Ks) (IC(50): 4.78 microM). Dexrazoxane significantly reduced the doxorubicin-induced QTc prolongation and prevented doxorubicin-induced inhibition of I(Ks). CONCLUSION AND IMPLICATIONS: Doxorubicin acutely prolonged the QT interval in guinea-pig heart by selective I(Ks) blockade. This effect was prevented by dexrazoxane. This result is important because it illustrates the danger of neglecting I(Ks) in favour of hERG screening alone, for early preclinical testing for possible induction of torsade de pointes.

Surgical outcome of scleral buckling compared with scleral buckling with vitrectomy for treatment of macula-off retinal detachment.

BACKGROUND AND OBJECTIVE: To compare the surgical outcome of scleral buckling (group 1) versus scleral buckling with pars plana vitrectomy (group 2) for the repair of macula-off rhegmatogenous retinal detachment without proliferative vitreoretinopathy. PATIENTS AND METHODS: A retrospective chart review was performed. RESULTS: Eighty-three patients were identified in group 1 and 63 patients in group 2. Presenting visual acuity was 4/200 in group 1 and 3/200 in group 2. Median duration of detachment prior to surgery was 5 days in group 1 and 6 days in group 2. There was no statistical difference in best-corrected (P = .59) or most recent (P = .75) visual acuity between groups. Median best-corrected visual acuity was 20/30 and median most recent visual acuity was 20/40 in both groups. Significantly more additional procedures were performed in group 1 than in group 2 (21.7% vs 7.9%, respectively; P = .024). The final reattachment rate was 96.4% in group 1 and 98.4% in group 2. Proliferative vitreoretinopathy developed in 15.7% of patients in group 1 and 4.8% in group 2 (P= .037). CONCLUSION: Visual outcome of scleral buckling is similar to scleral buckling with pars plana vitrectomy for the treatment of macula-off rhegmatogenous retinal detachment in patients without proliferative vitreoretinopathy. Patients undergoing scleral buckling only are at an increased risk of developing proliferative vitreoretinopathy and requiring additional procedures.

Radiation therapists' perspective on barriers to clinical trials research.

This study investigates the barriers to the conduct of research as perceived by radiation therapists (RT) particularly with regards to their activity as part of collaborative clinical trials groups such as the Trans-Tasman Radiation Oncology Group. These were examined to identify solutions that might promote research by RT working within busy clinical services. In September to October 2005, surveys were sent to an RT Educator and RT Chiefs in four public hospitals in New South Wales, Australia, with a request to distribute and collect the surveys from RT employed at their centres. The overall response rate across these centres was 59% (78/133). Most of the respondents felt that their managers regarded research to be of high priority (79%) and that others in their workplace considered initiating and conducting research as important (79%). The RT considered lack of time during working hours to be the greatest barrier to research (87%). However, the RT felt that the availability of a research mentor would facilitate research in their workplace (90%). Based on our findings, the availability of structural support from radiation oncology centres may promote the clinical trials research participation of RT.