Whole Genome Sequencing Identifies Novel Common and Low-Frequency Variants Associated With Age-Related Macular Degeneration.

Purpose: To identify associations of common, low-frequency, and rare variants with advanced age-related macular degeneration (AMD) using whole genome sequencing (WGS). Methods: WGS data were obtained for 2123 advanced AMD patients (participants of clinical trials for advanced AMD) and 2704 controls (participants of clinical trials for asthma [N = 2518] and Alzheimer's disease [N = 186]), and joint genotype calling was performed, followed by quality control of the dataset. Single variant association analyses were performed for all identified common, low-frequency, and rare variants. Gene-based tests were executed for rare and low-frequency variants using SKAT-O and three groups of variants based on putative impact information: (1) all variants, (2) modifier impact variants, and (3) high- and moderate-impact variants. To ascertain independence of the identified associations from previously reported AMD and asthma loci, conditional analyses were performed. Results: Previously identified AMD variants at the CFH, ARMS2/HTRA1, APOE, and C3 loci were associated with AMD at a genome-wide significance level. We identified new single variant associations for common variants near the PARK7 gene and in the long non-coding RNA AC103876.1, and for a rare variant near the TENM3 gene. In addition, gene-based association analyses identified a burden of modifier variants in eight intergenic and gene-spanning regions and of high- and moderate-impact variants in the C3, CFHR5, SLC16A8, and CFI genes. Conclusions: We describe the largest WGS study in AMD to date. We confirmed previously identified associations and identified several novel associations that are worth exploring in further follow-up studies.

Impairment of Multiple Mitochondrial Energy Metabolism Pathways in the Heart of Chagas Disease Cardiomyopathy Patients.

Chagas disease cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy occurring in 30% of the 6 million infected with the protozoan Trypanosoma cruzi in Latin America. Survival is significantly lower in CCC than ischemic (IC) and idiopathic dilated cardiomyopathy (DCM). Previous studies disclosed a selective decrease in mitochondrial ATP synthase alpha expression and creatine kinase activity in CCC myocardium as compared to IDC and IC, as well as decreased in vivo myocardial ATP production. Aiming to identify additional constraints in energy metabolism specific to CCC, we performed a proteomic study in myocardial tissue samples from CCC, IC and DCM obtained at transplantation, in comparison with control myocardial tissue samples from organ donors. Left ventricle free wall myocardial samples were subject to two-dimensional electrophoresis with fluorescent labeling (2D-DIGE) and protein identification by mass spectrometry. We found altered expression of proteins related to mitochondrial energy metabolism, cardiac remodeling, and oxidative stress in the 3 patient groups. Pathways analysis of proteins differentially expressed in CCC disclosed mitochondrial dysfunction, fatty acid metabolism and transmembrane potential of mitochondria. CCC patients' myocardium displayed reduced expression of 22 mitochondrial proteins belonging to energy metabolism pathways, as compared to 17 in DCM and 3 in IC. Significantly, 6 beta-oxidation enzymes were reduced in CCC, while only 2 of them were down-regulated in DCM and 1 in IC. We also observed that the cytokine IFN-gamma, previously described with increased levels in CCC, reduces mitochondrial membrane potential in cardiomyocytes. Results suggest a major reduction of mitochondrial energy metabolism and mitochondrial dysfunction in CCC myocardium which may be in part linked to IFN-gamma. This may partially explain the worse prognosis of CCC as compared to DCM or IC.

Semi-Quantitative Multiplex Profiling of the Complement System Identifies Associations of Complement Proteins with Genetic Variants and Metabolites in Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is a major cause of vision loss among the elderly in the Western world. The complement system has been identified as one of the main AMD disease pathways. We performed a comprehensive expression analysis of 32 complement proteins in plasma samples of 255 AMD patients and 221 control individuals using mass spectrometry-based semi-quantitative multiplex profiling. We detected significant associations of complement protein levels with age, sex and body-mass index (BMI), and potential associations of C-reactive protein, factor H related-2 (FHR-2) and collectin-11 with AMD. In addition, we confirmed previously described associations and identified new associations of AMD variants with complement levels. New associations include increased C4 levels for rs181705462 at the C2/CFB locus, decreased vitronectin (VTN) levels for rs11080055 at the TMEM97/VTN locus and decreased factor I levels for rs10033900 at the CFI locus. Finally, we detected significant associations between AMD-associated metabolites and complement proteins in plasma. The most significant complement-metabolite associations included increased high density lipoprotein (HDL) subparticle levels with decreased C3, factor H (FH) and VTN levels. The results of our study indicate that demographic factors, genetic variants and circulating metabolites are associated with complement protein components. We suggest that these factors should be considered to design personalized treatment approaches and to increase the success of clinical trials targeting the complement system.

Common haplotypes at the CFH locus and low-frequency variants in CFHR2 and CFHR5 associate with systemic FHR concentrations and age-related macular degeneration.

Age-related macular degeneration (AMD) is the principal cause of blindness in the elderly population. A strong effect on AMD risk has been reported for genetic variants at the CFH locus, encompassing complement factor H (CFH) and the complement-factor-H-related (CFHR) genes, but the underlying mechanisms are not fully understood. We aimed to dissect the role of factor H (FH) and FH-related (FHR) proteins in AMD in a cohort of 202 controls and 216 individuals with AMD. We detected elevated systemic levels of FHR-1 (p = 1.84 × 10-6), FHR-2 (p = 1.47 × 10-4), FHR-3 (p = 1.05 × 10-5) and FHR-4A (p = 1.22 × 10-2) in AMD, whereas FH concentrations remained unchanged. Common AMD genetic variants and haplotypes at the CFH locus strongly associated with FHR protein concentrations (e.g., FH p.Tyr402His and FHR-2 concentrations, p = 3.68 × 10-17), whereas the association with FH concentrations was limited. Furthermore, in an International AMD Genomics Consortium cohort of 17,596 controls and 15,894 individuals with AMD, we found that low-frequency and rare protein-altering CFHR2 and CFHR5 variants associated with AMD independently of all previously reported genome-wide association study (GWAS) signals (p = 5.03 × 10-3 and p = 2.81 × 10-6, respectively). Low-frequency variants in CFHR2 and CFHR5 led to reduced or absent FHR-2 and FHR-5 concentrations (e.g., p.Cys72Tyr in CFHR2 and FHR-2, p = 2.46 × 10-16). Finally, we showed localization of FHR-2 and FHR-5 in the choriocapillaris and in drusen. Our study identifies FHR proteins as key proteins in the AMD disease mechanism. Consequently, therapies that modulate FHR proteins might be effective for treating or preventing progression of AMD. Such therapies could target specific individuals with AMD on the basis of their genotypes at the CFH locus.

Safety and Efficacy of Different Doses and Regimens of Faricimab vs Ranibizumab in Neovascular Age-Related Macular Degeneration: The AVENUE Phase 2 Randomized Clinical Trial.

Importance: Faricimab, the first bispecific antibody designed for intraocular use, simultaneously and independently binds and neutralizes angiopoietin 2 (Ang-2) and vascular endothelial growth factor A (VEGF-A). Objective: To assess the efficacy and safety of different doses and regimens of faricimab vs ranibizumab in patients with neovascular age-related macular degeneration (nAMD). Design, Setting, and Participants: AVENUE was a 36-week, multiple-dose-regimen, active comparator-controlled, double-masked, phase 2 randomized clinical study performed at 58 sites in the United States. Eligible participants were anti-VEGF treatment naive with choroidal neovascularization secondary to nAMD and best-corrected visual acuity (BCVA) Early Treatment Diabetic Retinopathy Study (ETDRS) letter score of 73 (Snellen equivalent, 20/40) to 24 (Snellen equivalent, 20/320). Data were collected from August 11, 2015, to January 12, 2017, with the final patient visit completed September 26, 2017. Data were analyzed from August 11, 2015, to October 4, 2019. Interventions: Patients were randomized 3:2:2:2:3 to receive ranibizumab, 0.5 mg every 4 weeks (arm A [n = 68]); faricimab, 1.5 mg every 4 weeks (arm B [n = 47]); faricimab, 6.0 mg every 4 weeks (arm C [n = 42]); faricimab, 6.0 mg every 4 weeks until week 12, then faricimab, 6.0 mg every 8 weeks (arm D [n = 47]); and ranibizumab, 0.5 mg every 4 weeks until week 8, then faricimab, 6.0 mg every 4 weeks (arm E [n = 69]). Main Outcomes and Measures: Mean change in BCVA from baseline to week 36, proportion of participants gaining at least 15 letters, BCVA of 20/40 or better or 20/200 or worse, and ocular coherence tomographic outcomes in anti-VEGF treatment-naive participants (arms A, B, C, D) and from weeks 12 to 36 in those with incomplete response (participants in arms A and E with week 12 BCVA ETDRS letter score of ≤68 [Snellen equivalent, 20/50 or worse]). Results: A total of 263 participants were included in the analysis (172 [65.4%] female; 258 [98.1%] white; mean [SD] age, 78.3 [8.7] years). At week 36, adjusted mean change in BCVA vs ranibizumab was 1.6 (80% CI, -1.6 to 4.7) letters for arm B (P = .52), -1.6 (80% CI, -4.9 to 1.7) letters for arm C (P = .53), and -1.5 (80% CI, -4.6 to 1.6) letters for arm D (P = .53). For arm E, adjusted mean change from week 12 was -1.7 (80% CI, -3.8 to 0.4) letters (P = .30). Conclusions and Relevance: AVENUE did not meet its primary end point of superiority of faricimab over ranibizumab in BCVA at week 36. Although not superior to monthly ranibizumab as given in this trial, overall visual and anatomical gains noted with faricimab support pursuing phase 3 trials for a potential alternative to monthly anti-VEGF therapy. Faricimab showed no new or unexpected safety signals. Trial Registration: ClinicalTrials.gov Identifier: NCT02484690.

Development and evaluation of an ultrasensitive free VEGF-A immunoassay for analysis of human aqueous humor.

Aim: Novel bifunctional VEGF-A neutralizing therapies are being developed for the treatment of retinal vascular diseases such as age-related macular degeneration and diabetic retinopathy. In developing new therapeutic drugs, only small aqueous humor sample volumes are available for analyzing several parameters. Highly sensitive detection methods must be applied in analyzing VEGF-A levels in ocular fluids in order to demonstrate VEGF-A suppression following drug administration. Experimental: A highly sensitive immunoassay for VEGF-A was developed on the single molecule array (Simoa) platform, and validated before being used for the analysis of clinical aqueous humor samples from patients treated with anti-VEGF-A therapeutics. Results: This highly sensitive immunoassay allows the detection of baseline VEGF-A levels and suppression effects after drug administration, even in sample volumes as low as 12 µl. Conclusion: The Simoa VEGF-A assay is a valuable tool for the reliable monitoring of VEGF-A suppression after intravitreal administration of anti-VEGF-A drugs.

Simultaneous Inhibition of Angiopoietin-2 and Vascular Endothelial Growth Factor-A with Faricimab in Diabetic Macular Edema: BOULEVARD Phase 2 Randomized Trial.

PURPOSE: The phase 2 BOULEVARD trial compared safety and efficacy of faricimab, a novel bispecific antibody targeting angiopoietin-2 and vascular endothelial growth factor-A (VEGF-A), with ranibizumab in patients with diabetic macular edema (DME). DESIGN: The BOULEVARD trial (ClinicalTrials.gov identifier, NCT02699450) was a prospective, randomized, active comparator-controlled, double-masked, multicenter, phase 2 study conducted at 59 sites in the United States. PARTICIPANTS: The trial enrolled patients 18 years of age or older with center-involving DME, best-corrected visual acuity (BCVA) of 73 to 24 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, and central subfield thickness (CST) of 325 µm or more. METHODS: Anti-VEGF treatment-naïve patients were randomized 1:1:1 to intravitreal 6.0 mg faricimab, 1.5 mg faricimab, or 0.3 mg ranibizumab, and patients previously treated with anti-VEGF were randomized 1:1 to 6.0 mg faricimab or 0.3 mg ranibizumab. Patients were dosed monthly for 20 weeks, followed by an observation period up to week 36 to assess durability. MAIN OUTCOME MEASURES: The prespecified primary outcome measure was mean change in BCVA from baseline at week 24 for faricimab versus ranibizumab in treatment-naïve patients. Key secondary and exploratory outcome measures included CST, Diabetic Retinopathy Severity Scale (DRSS) score, and durability as assessed by time to re-treatment. RESULTS: The trial enrolled 229 patients (168 treatment-naïve and 61 previously treated with anti-VEGF). In treatment-naïve patients, 6.0 mg faricimab, 1.5 mg faricimab, and 0.3 mg ranibizumab resulted in mean improvements of 13.9, 11.7, and 10.3 ETDRS letters from baseline, respectively. The 6.0-mg faricimab dose demonstrated a statistically significant gain of 3.6 letters over ranibizumab (P = 0.03). In both patient populations, faricimab resulted in dose-dependent reductions in CST, improvements in DRSS score, and longer time to re-treatment during the observation period compared with ranibizumab. Faricimab showed no new or unexpected safety signals. CONCLUSIONS: The BOULEVARD trial met its primary end point; faricimab demonstrated statistically superior visual acuity gains versus ranibizumab at week 24 in treatment-naïve patients. Central subfield thickness reduction, DRSS score improvement, and extended durability outcomes support the primary outcome. These findings suggest the benefit of simultaneous inhibition of angiopoietin-2 and VEGF-A with faricimab for patients with DME.

A new perspective on lipid research in age-related macular degeneration.

There is an urgency to find new treatment strategies that could prevent or delay the onset or progression of AMD. Different classes of lipids and lipoproteins metabolism genes have been associated with AMD in a multiple ways, but despite the ever-increasing knowledge base, we still do not understand fully how circulating lipids or local lipid metabolism contribute to AMD. It is essential to clarify whether dietary lipids, systemic or local lipoprotein metabolismtrafficking of lipids in the retina should be targeted in the disease. In this article, we critically evaluate what has been reported in the literature and identify new directions needed to bring about a significant advance in our understanding of the role for lipids in AMD. This may help to develop potential new treatment strategies through targeting the lipid homeostasis.

A mega-analysis of expression quantitative trait loci (eQTL) provides insight into the regulatory architecture of gene expression variation in liver.

Genome-wide association studies (GWAS) have identified numerous genetic variants in the human genome associated with diseases and traits. Nevertheless, for most loci the causative variant is still unknown. Expression quantitative trait loci (eQTL) in disease relevant tissues is an excellent approach to correlate genetic association with gene expression. While liver is the primary site of gene transcription for two pathways relevant to age-related macular degeneration (AMD), namely the complement system and cholesterol metabolism, we explored the contribution of AMD associated variants to modulate liver gene expression. We extracted publicly available data and computed the largest eQTL data set for liver tissue to date. Genotypes and expression data from all studies underwent rigorous quality control. Subsequently, Matrix eQTL was used to identify significant local eQTL. In total, liver samples from 588 individuals revealed 202,489 significant eQTL variants affecting 1,959 genes (Q-Value < 0.001). In addition, a further 101 independent eQTL signals were identified in 93 of the 1,959 eQTL genes. Importantly, our results independently reinforce the notion that high density lipoprotein metabolism plays a role in AMD pathogenesis. Taken together, our study generated a first comprehensive map reflecting the genetic regulatory landscape of gene expression in liver.

Systems biology of the IMIDIA biobank from organ donors and pancreatectomised patients defines a novel transcriptomic signature of islets from individuals with type 2 diabetes.

AIMS/HYPOTHESIS: Pancreatic islet beta cell failure causes type 2 diabetes in humans. To identify transcriptomic changes in type 2 diabetic islets, the Innovative Medicines Initiative for Diabetes: Improving beta-cell function and identification of diagnostic biomarkers for treatment monitoring in Diabetes (IMIDIA) consortium ( www.imidia.org ) established a comprehensive, unique multicentre biobank of human islets and pancreas tissues from organ donors and metabolically phenotyped pancreatectomised patients (PPP). METHODS: Affymetrix microarrays were used to assess the islet transcriptome of islets isolated either by enzymatic digestion from 103 organ donors (OD), including 84 non-diabetic and 19 type 2 diabetic individuals, or by laser capture microdissection (LCM) from surgical specimens of 103 PPP, including 32 non-diabetic, 36 with type 2 diabetes, 15 with impaired glucose tolerance (IGT) and 20 with recent-onset diabetes (<1 year), conceivably secondary to the pancreatic disorder leading to surgery (type 3c diabetes). Bioinformatics tools were used to (1) compare the islet transcriptome of type 2 diabetic vs non-diabetic OD and PPP as well as vs IGT and type 3c diabetes within the PPP group; and (2) identify transcription factors driving gene co-expression modules correlated with insulin secretion ex vivo and glucose tolerance in vivo. Selected genes of interest were validated for their expression and function in beta cells. RESULTS: Comparative transcriptomic analysis identified 19 genes differentially expressed (false discovery rate ≤0.05, fold change ≥1.5) in type 2 diabetic vs non-diabetic islets from OD and PPP. Nine out of these 19 dysregulated genes were not previously reported to be dysregulated in type 2 diabetic islets. Signature genes included TMEM37, which inhibited Ca2+-influx and insulin secretion in beta cells, and ARG2 and PPP1R1A, which promoted insulin secretion. Systems biology approaches identified HNF1A, PDX1 and REST as drivers of gene co-expression modules correlated with impaired insulin secretion or glucose tolerance, and 14 out of 19 differentially expressed type 2 diabetic islet signature genes were enriched in these modules. None of these signature genes was significantly dysregulated in islets of PPP with impaired glucose tolerance or type 3c diabetes. CONCLUSIONS/INTERPRETATION: These studies enabled the stringent definition of a novel transcriptomic signature of type 2 diabetic islets, regardless of islet source and isolation procedure. Lack of this signature in islets from PPP with IGT or type 3c diabetes indicates differences possibly due to peculiarities of these hyperglycaemic conditions and/or a role for duration and severity of hyperglycaemia. Alternatively, these transcriptomic changes capture, but may not precede, beta cell failure.

Targeting key angiogenic pathways with a bispecific CrossMAb optimized for neovascular eye diseases.

Anti-angiogenic therapies using biological molecules that neutralize vascular endothelial growth factor-A (VEGF-A) have revolutionized treatment of retinal vascular diseases including age-related macular degeneration (AMD). This study reports preclinical assessment of a strategy to enhance anti-VEGF-A monotherapy efficacy by targeting both VEGF-A and angiopoietin-2 (ANG-2), a factor strongly upregulated in vitreous fluids of patients with retinal vascular disease and exerting some of its activities in concert with VEGF-A. Simultaneous VEGF-A and ANG-2 inhibition was found to reduce vessel lesion number, permeability, retinal edema, and neuron loss more effectively than either agent alone in a spontaneous choroidal neovascularization (CNV) model. We describe the generation of a bispecific domain-exchanged (crossed) monoclonal antibody (CrossMAb; RG7716) capable of binding, neutralizing, and depleting VEGF-A and ANG-2. RG7716 showed greater efficacy than anti-VEGF-A alone in a non-human primate laser-induced CNV model after intravitreal delivery. Modification of RG7716's FcRn and FcγR binding sites disabled the antibodies' Fc-mediated effector functions. This resulted in increased systemic, but not ocular, clearance. These properties make RG7716 a potential next-generation therapy for neovascular indications of the eye.

LYSOPHOSPHATIDIC ACIDS AND AUTOTAXIN IN RETINAL VEIN OCCLUSION.

PURPOSE: To analyze the levels of lysophosphatidic acids (LPAs) and autotaxin (ATX) in undiluted vitreous of untreated patients with retinal vein occlusion (RVO). METHODS: Sixty-four vitreous samples (40 RVO, 24 controls with idiopathic floaters) were analyzed in this retrospective case series using LC/MS for LPAs 16:0, 18:0, 18:1, 20:4, and ELISA kits or Luminex technology for ATX, angiopoetin-1 (ANG-1), interleukin-6 (IL-6), interleukin-7 (IL-7), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), pigment epithelium-derived factor (PEDF), and vascular endothelial growth factor (VEGF). LPA and ATX levels were correlated with the visual acuity, central macular thickness (CMT), average retinal thickness (AvT), vitreal cytokine levels and with each other. RESULTS: Levels of every LPA species tested and ATX were significantly increased in the vitreous fluid from all patients with RVO (total LPAs: 968.0 ± 842.3 nM; ATX: 2.5 ± 1.02 nM) compared with controls (total LPAs: 225.2 ± 292.8 nM, P < 0.0001; ATX: 1.9 ± 1.00 nM, P = 0.005). There were strong positive correlations between the vitreal levels of IL-6, IL-8, MCP-1, VEGF and LPAs. CONCLUSION: Levels of LPAs and ATX were positively correlated with proinflammatory cytokines and VEGF and might thus play an important role in the development of macular edema secondary to RVO.

Biomarkers of rapid chronic kidney disease progression in type 2 diabetes.

Here we evaluated the performance of a large set of serum biomarkers for the prediction of rapid progression of chronic kidney disease (CKD) in patients with type 2 diabetes. We used a case-control design nested within a prospective cohort of patients with baseline eGFR 30-60 ml/min per 1.73 m(2). Within a 3.5-year period of Go-DARTS study patients, 154 had over a 40% eGFR decline and 153 controls maintained over 95% of baseline eGFR. A total of 207 serum biomarkers were measured and logistic regression was used with forward selection to choose a subset that were maximized on top of clinical variables including age, gender, hemoglobin A1c, eGFR, and albuminuria. Nested cross-validation determined the best number of biomarkers to retain and evaluate for predictive performance. Ultimately, 30 biomarkers showed significant associations with rapid progression and adjusted for clinical characteristics. A panel of 14 biomarkers increased the area under the ROC curve from 0.706 (clinical data alone) to 0.868. Biomarkers selected included fibroblast growth factor-21, the symmetric to asymmetric dimethylarginine ratio, ß2-microglobulin, C16-acylcarnitine, and kidney injury molecule-1. Use of more extensive clinical data including prebaseline eGFR slope improved prediction but to a lesser extent than biomarkers (area under the ROC curve of 0.793). Thus we identified several novel associations of biomarkers with CKD progression and the utility of a small panel of biomarkers to improve prediction.

Protein biomarkers for the prediction of cardiovascular disease in type 2 diabetes.

AIMS/HYPOTHESIS: We selected the most informative protein biomarkers for the prediction of incident cardiovascular disease (CVD) in people with type 2 diabetes. METHODS: In this nested case-control study we measured 42 candidate CVD biomarkers in 1,123 incident CVD cases and 1,187 controls with type 2 diabetes selected from five European centres. Combinations of biomarkers were selected using cross-validated logistic regression models. Model prediction was assessed using the area under the receiver operating characteristic curve (AUROC). RESULTS: Sixteen biomarkers showed univariate associations with incident CVD. The most predictive subset selected by forward selection methods contained six biomarkers: N-terminal pro-B-type natriuretic peptide (OR 1.69 per 1 SD, 95% CI 1.47, 1.95), high-sensitivity troponin T (OR 1.29, 95% CI 1.11, 1.51), IL-6 (OR 1.13, 95% CI 1.02, 1.25), IL-15 (OR 1.15, 95% CI 1.01, 1.31), apolipoprotein C-III (OR 0.79, 95% CI 0.70, 0.88) and soluble receptor for AGE (OR 0.84, 95% CI 0.76, 0.94). The prediction of CVD beyond clinical covariates improved from an AUROC of 0.66 to 0.72 (AUROC for Framingham Risk Score covariates 0.59). In addition to the biomarkers, the most important clinical covariates for improving prediction beyond the Framingham covariates were estimated GFR, insulin therapy and HbA1c. CONCLUSIONS/INTERPRETATION: We identified six protein biomarkers that in combination with clinical covariates improved the prediction of our model beyond the Framingham Score covariates. Biomarkers can contribute to improved prediction of CVD in diabetes but clinical data including measures of renal function and diabetes-specific factors not included in the Framingham Risk Score are also needed.

Cardiovascular risk markers associated with arterial calcification in patients with chronic kidney disease Stages 3 and 4.

BACKGROUND: The contribution of pro-inflammatory markers to cardiovascular (CV) risk and vascular calcification in chronic kidney disease (CKD) remains largely to be elucidated. We investigated the association between plasma levels of several biomarkers and calcification volume in three different vascular beds in CKD Stages 3 and 4 patients. METHODS: This is a cross-sectional, exploratory study in patients with an estimated glomerular filtration rate (eGFR) ≥20 and ≤45 mL/min/1.73 m2 and serum phosphorus ≥3.5 and <6.0 mg/dL enrolled in a previously published randomized, double blind, placebo-controlled single-centre trial. Ethylenediaminetetraacetic acid (EDTA) plasma samples were collected at baseline before patients received study medication and analysed for the presence of a number of biomarkers. Coronary artery calcium (CAC), thoracic aortic calcification (TAC) and abdominal aortic calcification (AAC) volumes were measured using standard electron-beam computed tomography protocols. Associations were adjusted for age, sex, smoking, body mass index, diabetes mellitus status, low-density lipoprotein cholesterol (LDL-C), systolic blood pressure and eGFR. RESULTS: Associations with CAC were found for ß2-microglobulin (B2M), fibroblast growth factor 23 (FGF23), interleukin-8 (IL-8) and IL-18. AAC was associated with: B2M, FGF23 and IL-2 receptor alpha (IL-2 RA). TAC was associated with: B2M, FGF23, IL-2 RA, IL-18 and tumour necrosis factor receptor type I. For most of the analysed biomarkers, there were non-significant trends of associations with calcification. CONCLUSIONS: This exploratory study found that elevated plasma levels of several inflammatory biomarkers are significantly associated with arterial calcification in CKD Stages 3 and 4 patients. A greater understanding of inflammation and calcification in CKD patients may help the development of CV risk-assessment algorithms for better management of these patients.

Adhesion molecules affected by treatment of lung cancer cells with epidermal growth factor.

Lung cancer is one of the leading causes of death in the world. Some tumor events are attributed to an important group of molecules (cadherins and integrins). We evaluated the interactions of cell adhesion molecules in cell lines from lung cancer. Two lung cancer cell lines were nonmetastatic (H358 and H441) and two were metastatic (H1299 and H292). All cell lines were treated with epidermal growth factor (EGF), and Western blot analysis was performed to assess the interactions between these proteins. The bronchoalveolar cells H358 showed the three analyzed proteins: E-cadherin, ß-catenin, and p120 catenin. The adenocarcinoma cells H441 did not present p120 catenin, and carcinoma cells did not show E-cadherin (H1299) or p120 catenin (H292). FAK (pTyr925) was dephosphorylated in adenocarcinoma cells H441, absent in carcinoma cells H1299, and upregulated in the other carcinoma cells H292. p130Cas showed no difference when the cell lines were treated with EGF for 30 min; it was absent in the metastatic carcinoma cells H1299. Paxillin was dephosphorylated in adenocarcinoma cells H441 and also absent in other metastatic carcinoma cells H292. Vinculin showed the same results, and talin was downregulated in adenocarcinoma cells H441 when the cells were treated with EGF. Rap1 was downregulated and PYK2 was upregulated in the same cell line. Our data help to comprehend the mechanism involved in cell migration to the blood and metastasis generation. In conclusion, the expression patterns of cell-cell adhesion were not affected by EGF treatment but it affected cell-extracellular matrix adhesion.

Genetic variants of the DDR1 gene are associated with vitiligo in two independent Brazilian population samples.

Vitiligo is a chronic disease characterized by macules devoid of melanin and identifiable melanocytes. Adhesion of melanocytes to the basement membrane by integrin CCN3 is mediated through collagen IV receptor DDR1. We hypothesize that genetic variants of the DDR1 gene are associated with the occurrence of vitiligo. To test this hypothesis, we genotyped 10 DDR1 tag single-nucleotide polymorphisms (SNPs) in 212 trios composed of an affected child and both parents. Associated markers were then genotyped in 134 independent, unrelated individuals with vitiligo and 134 unrelated controls. Allele T of tag SNP rs4618569 was associated with an increased risk for vitiligo in the family trios (P=0.002, odds ratio (OR)=5.27; 95% confidence interval (CI)=1.59-17.40), whereas allele C of tag SNP rs2267641 was associated with an increased risk for vitiligo in both family-based and case-control populations (P=0.01, OR=3.47; 95% CI=1.22-9.17; P=0.04, OR=6.00; 95% CI=1.73-52.33, respectively). The best evidence for association in the trios was obtained for a haplotype composed of risk alleles of markers rs4618569 and rs2267641 (P=0.0006). There was an age-dependent enrichment of rs4618569 T allele and rs2267641 C allele in early-onset affected individuals. In conclusion, we propose DDR1 as a susceptibility gene for vitiligo, possibly implicating a defective cell adhesion in vitiligo pathogenesis.

Multifunctional class I transcription in Trypanosoma brucei depends on a novel protein complex.

The vector-borne, protistan parasite Trypanosoma brucei is the only known eukaryote with a multifunctional RNA polymerase I that, in addition to ribosomal genes, transcribes genes encoding the parasite's major cell-surface proteins-the variant surface glycoprotein (VSG) and procyclin. In the mammalian bloodstream, antigenic variation of the VSG coat is the parasite's means to evade the immune response, while procyclin is necessary for effective establishment of trypanosome infection in the fly. Moreover, the exceptionally high efficiency of mono-allelic VSG expression is essential to bloodstream trypanosomes since its silencing caused rapid cell-cycle arrest in vitro and clearance of parasites from infected mice. Here we describe a novel protein complex that recognizes class I promoters and is indispensable for class I transcription; it consists of a dynein light chain and six polypeptides that are conserved only among trypanosomatid parasites. In accordance with an essential transcriptional function of the complex, silencing the expression of a key subunit was lethal to bloodstream trypanosomes and specifically affected the abundance of rRNA and VSG mRNA. The complex was dubbed class I transcription factor A.