Microvascular dysfunction has been suggested to be a major pathogenic factor
for the development of hypertension. We examined the association between retinal
vascular caliber, a marker of systemic microvascular dysfunction, and incident
hypertension on a meta-analysis of individual participant data.
We performed a systematic review with relevant studies identified through a
search of electronic databases, a review of reference lists, and correspondence with
experts. Studies were included if participants were selected from a general population,
retinal vascular caliber was measured from photographs using computer-assisted methods
at baseline, and individuals were followed up to ascertain the incidence of
hypertension. Prespecified individual recorded data from six population-based
prospective cohort studies were included. Discrete time proportional odds models were
constructed for each study with adjustment for hypertension risk factors. Log odds
ratios (ORs) per 20-μm difference were pooled using random-effects
Among 10 229 participants without prevalent hypertension, diabetes, or
cardiovascular disease, 2599 developed new-onset hypertension during median follow-up
periods ranging from 2.9 to 10 years. Both narrower retinal arterioles [pooled
multivariate-adjusted OR per 20-μm difference 1.29, 95% confidence
interval (CI) 1.20–1.39] and wider venules (OR per 20-μm
difference 1.14, 95% CI 1.06–1.23) were associated with an increased
risk of hypertension. Each 20 μm narrower arterioles at baseline were associated
with a 1.12 mmHg (95% CI 0.25–1.99) greater increase in SBP over 5
Retinal arteriolar narrowing and venular widening were independently associated
with an increased risk of hypertension. These findings underscore the importance of
microvascular remodeling in the pathogenesis of hypertension.
hypertension; meta-analysis; microvascular dysfunction
To determine if open-angle glaucoma (OAG)-associated single nucleotide polymorphisms (SNPs) are associated with incident glaucoma and if such genetic information is useful in OAG risk prediction.
Case-control from within a population-based longitudinal study.
study population: Individuals aged over 49 years of age living in the Blue Mountains region west of Sydney and enrolled in the Blue Mountains Eye Study. observation: Cases for this sub-study (n = 67) developed incident OAG between baseline and 10-year visits, in either eye, while controls (n = 1919) had no evidence for OAG at any visit. All participants had an ocular examination and DNA genotyped for reported OAG risk SNPs. main outcome measure: Incident OAG.
Two loci also known to be associated with cup-to-disc ratio as well as OAG (9p21 near CDKN2B-AS1 and SIX1/SIX6) were both significantly associated with incident OAG in the Blue Mountains Eye Study cohort (P = .006 and P = .004, respectively). The TMCO1 locus was nominally associated (P = .012), while the CAV1/CAV2 and 8q22 loci were not associated. Multivariate logistic regression and neural network analysis both indicated that the genetic risk factors contributed positively to the predictive models incorporating traditional risk factors.
This study shows that previously reported genetic variations related to OAG and cup-to-disc ratio are associated with the onset of OAG and thus may become useful in risk prediction algorithms designed to target early treatment to those most at risk of developing glaucoma.
Prediction models for age-related macular degeneration (AMD) based on case-control studies have a tendency to overestimate risks. The aim of this study is to develop a prediction model for late AMD based on data from population-based studies.
Three population-based studies: the Rotterdam Study (RS), the Beaver Dam Eye Study (BDES), and the Blue Mountains Eye Study (BMES) from the Three Continent AMD Consortium (3CC).
People (n = 10106) with gradable fundus photographs, genotype data, and follow-up data without late AMD at baseline.
Features of AMD were graded on fundus photographs using the 3CC AMD severity scale. Associations with known genetic and environmental AMD risk factors were tested using Cox proportional hazard analysis. In the RS, the prediction of AMD was estimated for multivariate models by area under receiver operating characteristic curves (AUCs). The best model was validated in the BDES and BMES, and associations of variables were re-estimated in the pooled data set. Beta coefficients were used to construct a risk score, and risk of incident late AMD was calculated using Cox proportional hazard analysis. Cumulative incident risks were estimated using Kaplan–Meier product-limit analysis.
Main Outcome Measures
Incident late AMD determined per visit during a median follow-up period of 11.1 years with a total of 4 to 5 visits.
Overall, 363 participants developed incident late AMD, 3378 participants developed early AMD, and 6365 participants remained free of any AMD. The highest AUC was achieved with a model including age, sex, 26 single nucleotide polymorphisms in AMD risk genes, smoking, body mass index, and baseline AMD phenotype. The AUC of this model was 0.88 in the RS, 0.85 in the BDES and BMES at validation, and 0.87 in the pooled analysis. Individuals with low-risk scores had a hazard ratio (HR) of 0.02 (95% confidence interval [CI], 0.01–0.04) to develop late AMD, and individuals with high-risk scores had an HR of 22.0 (95% CI, 15.2–31.8). Cumulative risk of incident late AMD ranged from virtually 0 to more than 65% for those with the highest risk scores.
Our prediction model is robust and distinguishes well between those who will develop late AMD and those who will not. Estimated risks were lower in these population-based studies than in previous case-control studies.
Improved understanding of molecular drivers of carcinogenesis has led to significant progress in the management of lung cancer. Patients with non-small-cell lung cancer (NSCLC) with anaplastic lymphoma kinase (ALK) gene rearrangements constitute about 4%–5% of all NSCLC patients. ALK+ NSCLC cells respond well to small molecule ALK inhibitors such as crizotinib; however, resistance invariably develops after several months of treatment. There are now several newer ALK inhibitors, with the next generation of agents targeting resistance mutations. In this review, we will discuss the prevalence and clinical characteristics of ALK+ lung cancer, current treatment options, and future directions in the management of this subset of NSCLC patients.
anaplastic lymphoma kinase (ALK); gene rearrangements; lung cancer; kinase inhibitors; lung adenocarcinoma
Fractal dimensions (FDs) are frequently used for summarizing the complexity of retinal vascular. However, previous techniques on this topic were not zone specific. A new methodology to measure FD of a specific zone in retinal images has been developed and tested as a marker for stroke prediction. Higuchi's fractal dimension was measured in circumferential direction (FDC) with respect to optic disk (OD), in three concentric regions between OD boundary and 1.5 OD diameter from its margin. The significance of its association with future episode of stroke event was tested using the Blue Mountain Eye Study (BMES) database and compared against spectrum fractal dimension (SFD) and box-counting (BC) dimension. Kruskal-Wallis analysis revealed FDC as a better predictor of stroke (H = 5.80, P = 0.016, α = 0.05) compared with SFD (H = 0.51, P = 0.475, α = 0.05) and BC (H = 0.41, P = 0.520, α = 0.05) with overall lower median value for the cases compared to the control group. This work has shown that there is a significant association between zone specific FDC of eye fundus images with future episode of stroke while this difference is not significant when other FD methods are employed.
Age-related macular degeneration (AMD) is a leading cause of irreversible central visual loss in the elderly. A recent genome-wide association studies (GWAS) reported that rs9621532 near the tissue inhibitor of metalloproteinase 3 (TIMP3)/synapsin III (SYN3) region of 22q12.3 is associated with AMD. In this study, we characterize its phenotypic influence on AMD using three independent study cohorts: case–control studies from the National Eye Institute Clinical Center (NEI, n=397) and the Age-Related Eye Disease Study (n=523) as well as a nested case–control study from Blue Mountains Eye Study (BMES, n=852). Comparisons between cases and controls show no association between rs9621532 and AMD in the three sample sets. However, stratifying NEI cases uncovers a moderate protective role of rs9621532 in neovascular AMD (nAMD) and the association adhered to a dominant model (odds ratios=0.32; 95% CI: 0.11–0.89; P=0.02). The BMES data followed the same pattern of association with nAMD as that seen in the NEI sample but did not reach statistical significance. Polychotomous logistic regression showed a trend that rs9621532 correlates with less severe disease, for example, with the majority of carriers having intermediate AMD rather than nAMD/geographic atrophy AMD. Functionally, rs9621532 influences TIMP3 mRNA expression in cultured primary human fetal retinal pigment epithelium (hfRPE) cells. In hfRPE donors carrying the protective rs9625132 allele, we measured a reduction in TIMP3 mRNA by quantitative RT-PCR. Our data suggest that rs9621532 carriers have a lower risk of developing nAMD, potentially because of decreased transcription of TIMP3.
age-related macular degeneration; TIMP3; phenotype; single-nucleotide polymorphism; Blue Mountains Eye Study; Age-Related Eye Diseases Study
Although assessment of hypertensive retinopathy signs has been recommended for determining end-organ damage and stratifying vascular risk in hypertensive persons, its value remains unclear. In this study, we examine whether hypertensive retinopathy predicts the long-term risk of stroke in hypertensives.
A total of 2907 hypertensive participants aged 50–73 at the 1993–1995 examination, who had gradable retinal photographs, no history of diabetes, stroke and coronary heart disease at baseline and data on incident stroke were included from the Atherosclerosis Risk in Communities (ARIC) Study. Retinal photographs were assessed for hypertensive retinopathy signs and classified as none, mild, and moderate/severe. Incident events of any stroke, cerebral infarction and hemorrhagic stroke were identified and validated.
After a mean follow-up period of 13.0 years, 165 persons developed incident stroke (146 cerebral infarctions and 15 hemorrhagic strokes). After adjusting for age, sex, blood pressure, and other risk factors, persons with moderate hypertensive retinopathy were more likely to have stroke (multivariable hazard ratios (HR), moderate versus no retinopathy: 2.37, 95%CI 1.39-4.02). In hypertensives on medication with good control of blood pressure, hypertensive retinopathy was related to an increased risk of cerebral infarction (HR, mild retinopathy: 1.96, 95%CI 1.09-3.55; moderate retinopathy: 2.98, 95%CI 1.01-8.83).
Hypertensive retinopathy predicts the long-term risk of stroke, independent of blood pressure, even in treated hypertensives with good hypertension control. Retinal photographic assessment of hypertensive retinopathy signs may be useful for assessment of stroke risk.
Hypertension; Hypertensive retinopathy; Stroke; Cerebral infarction
Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10−8), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10−11) and 8q12 (minimum p value 1.82×10−11) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. “Replication-level” association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.
The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers.
Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken at baseline examination, 1992–4. Retinal arteriolar and venular calibers were measured from digitized retinal photographs using a validated semi-automated computer program.
All analyses adjusted for age, sex, systolic blood pressure, diabetes, smoking and fellow vessel caliber. Higher hematocrit, white cell count and platelet count were associated with narrower arteriolar caliber (p = 0.02, 0.03 and 0.001 respectively), while higher hemoglobin, hematocrit, red cell count, white cell count and platelet count were associated with wider venular caliber (p<0.0001 for all). Each quintile increase in hematocrit, white cell count and platelet count was associated with approximately 0.5 µm narrower arteriolar caliber; whereas each quintile increase in all of the complete blood count components was associated with approximately 1–2 µm wider venular caliber.
These associations show that elevated levels of hematological indices can have adverse effects on the microcirculation.
Visual refractive errors (REs) are complex genetic traits with a largely unknown etiology. To date, genome-wide association studies (GWASs) of moderate size have identified several novel risk markers for RE, measured here as mean spherical equivalent (MSE). We performed a GWAS using a total of 7280 samples from five cohorts: the Age-Related Eye Disease Study (AREDS); the KORA study (‘Cooperative Health Research in the Region of Augsburg’); the Framingham Eye Study (FES); the Ogliastra Genetic Park-Talana (OGP-Talana) Study and the Multiethnic Study of Atherosclerosis (MESA). Genotyping was performed on Illumina and Affymetrix platforms with additional markers imputed to the HapMap II reference panel. We identified a new genome-wide significant locus on chromosome 16 (rs10500355, P = 3.9 × 10−9) in a combined discovery and replication set (26 953 samples). This single nucleotide polymorphism (SNP) is located within the RBFOX1 gene which is a neuron-specific splicing factor regulating a wide range of alternative splicing events implicated in neuronal development and maturation, including transcription factors, other splicing factors and synaptic proteins.
Intravitreal injections of anti-vascular endothelial growth factor agents, such as ranibizumab, have significantly improved the management of neovascular age-related macular degeneration. This study used patient-level simulation modelling to estimate the number of individuals in Australia who would have been likely to avoid legal blindness or visual impairment due to neovascular age-related macular degeneration over a 2-year period as a result of intravitreal ranibizumab injections. The modelling approach used existing data for the incidence of neovascular age-related macular degeneration in Australia and outcomes from ranibizumab trials. Blindness and visual impairment were defined as visual acuity in the better-seeing eye of worse than 6/60 or 6/12, respectively. In 2010, 14 634 individuals in Australia were estimated to develop neovascular age-related macular degeneration who would be eligible for ranibizumab therapy. Without treatment, 2246 individuals would become legally blind over 2 years. Monthly 0.5 mg intravitreal ranibizumab would reduce incident blindness by 72% (95% simulation interval, 70–74%). Ranibizumab given as needed would reduce incident blindness by 68% (64–71%). Without treatment, 4846 individuals would become visually impaired over 2 years; this proportion would be reduced by 37% (34–39%) with monthly intravitreal ranibizumab, and by 28% (23–33%) with ranibizumab given as needed. These data suggest that intravitreal injections of ranibizumab, given either monthly or as needed, can substantially lower the number of cases of blindness and visual impairment over 2 years after the diagnosis of neovascular age-related macular degeneration.
Mucin 1 antigen, highly expressed by epithelial ovarian cancer (EOC), is a potential target for immunotherapy. A previous successful phase 1 trial was conducted in patients with adenocarcinoma who were injected with Cvac, autologous monocyte-derived dendritic cells (DCs) incubated with mannosylated mucin 1 protein (M-FP). The present study was a phase 2 trial of Cvac in patients with advanced EOC.
Eligible patients had EOC with progressive disease, defined as an increase in CA125 of ≥ 25% in 1 month. The primary endpoint was CA125 response or stabilization. Peripheral blood mononuclear cells were collected by leukapheresis and cultured to generate DCs. The DC were incubated with M-FP, and after washing were prepared for injection into the patient intradermally every 4 weeks for 3 doses, then every 10 weeks for up to 12 months.
All 28 patients recruited were evaluable for safety and 26 for efficacy. All had undergone surgery and platinum-based chemotherapy, and 57% of patients received ≥ 3 chemotherapy regimens. There were no Grade 3 or 4 toxicities considered related to Cvac. Four patients showed CA125 response or stabilization (2 patients with major responses, 1 minor response, 1 stabilization) of median duration 10.3 months (5.3–16.3 months). An additional patient had > 25% CA125 reduction (not confirmed).
Cvac immunotherapy was well tolerated. Clinical activity in EOC was evident based on decline or stabilization of CA125 in some patients, supporting ongoing development of Cvac in ovarian carcinoma and planning of additional trials of patients in remission is currently underway.
Ovarian cancer; Immunotherapy; CA125
To investigate the risk factors for myopia, including near work and outdoor activity, in Singapore Chinese preschool children.
A cross-sectional study, with disproportionate random sampling by 6-month age groups, of 3009 Singapore Chinese children aged 6–72 months was performed. Information on family history, near work and outdoor activity was obtained. Spherical equivalent refraction (SEA) was assessed.
Children with two myopic parents were more likely to be myopic (adjusted OR=1.91; 95% CI 1.38 to 2.63) and to have a more myopic SER (regression coefficient=−0.35; 95% CI −0.47 to −0.22) than children without myopic parents. For each 1 cm taller height, the SER was more myopic by 0.01 dioptres. Neither near work nor outdoor activity was associated with preschool myopia.
A family history of myopia was the strongest factor associated with preschool myopia. In contrast, neither near work nor outdoor activity was found to be associated with early myopia. These data suggest that genetic factors may play a more substantial role in the development of early-onset myopia than key environmental factors.
DNA repair genes that have been inactivated by promoter methylation offer potential therapeutic targets either by targeting the specific repair deficiency, or by synthetic lethal approaches. This study evaluated promoter methylation status for eight selected DNA repair genes (ATM, BRCA1, ERCC1, MGMT, MLH1, NEIL1, RAD23B and XPC) in 56 non-small cell lung cancer (NSCLC) tumours and 11 lung cell lines using the methylation-sensitive high resolution melting (MS-HRM) methodology. Frequent methylation in NEIL1 (42%) and infrequent methylation in ERCC1 (2%) and RAD23B (2%) are reported for the first time in NSCLC. MGMT methylation was detected in 13% of the NSCLCs. Contrary to previous studies, methylation was not detected in ATM, BRCA1, MLH1 and XPC. Data from The Cancer Genome Atlas (TCGA) was consistent with these findings. The study emphasises the importance of using appropriate methodology for accurate assessment of promoter methylation.
Glaucoma is a major cause of blindness in the world. To date, common genetic variants associated with glaucoma only explain a small proportion of its heritability. We performed a genome-wide association study of intra-ocular pressure (IOP), an underlying endophenotype for glaucoma. The discovery phase of the study was carried out in the TwinsUK cohort (N = 2774) analyzing association between IOP and single nucleotide polymorphisms (SNPs) imputed to HapMap2. The results were validated in 12 independent replication cohorts of European ancestry (combined N = 22 789) that were a part of the International Glaucoma Genetics Consortium. Expression quantitative trait locus (eQTL) analyses of the significantly associated SNPs were performed using data from the Multiple Tissue Human Expression Resource (MuTHER) Study. In the TwinsUK cohort, IOP was significantly associated with a number of SNPs at 9q33.3 (P = 3.48 × 10−8 for rs2286885, the most significantly associated SNP at this locus), within the genomic sequence of the FAM125B gene. Independent replication in a composite panel of 12 cohorts revealed consistent direction of effect and significant association (P = 0.003, for fixed-effect meta-analysis). Suggestive evidence for an eQTL effect of rs2286885 was observed for one of the probes targeting the coding region of the FAM125B gene. This gene codes for a component of a membrane complex involved in vesicular trafficking process, a function similar to that of the Caveolin genes (CAV1 and CAV2) which have previously been associated with primary open-angle glaucoma. This study suggests a novel association between SNPs in FAM125B and IOP in the TwinsUK cohort, though further studies to elucidate the functional role of this gene in glaucoma are necessary.
Central corneal thickness (CCT) is associated with eye conditions including keratoconus and glaucoma. We performed a meta-analysis on >20,000 individuals in European and Asian populations that identified 16 new loci associated with CCT at genome-wide significance (P < 5 × 10−8). We further showed that 2 CCT-associated loci, FOXO1 and FNDC3B, conferred relatively large risks for keratoconus in 2 cohorts with 874 cases and 6,085 controls (rs2721051 near FOXO1 had odds ratio (OR) = 1.62, 95% confidence interval (CI) = 1.4–1.88, P = 2.7 × 10−10, and rs4894535 in FNDC3B had OR = 1.47, 95% CI = 1.29–1.68, P = 4.9 × 10−9). FNDC3B was also associated with primary open-angle glaucoma (P = 5.6 × 10−4; tested in 3 cohorts with 2,979 cases and 7,399 controls). Further analyses implicate the collagen and extracellular matrix pathways in the regulation of CCT.
Combination blockade of human epidermal growth factor receptor (HER) family signaling may confer enhanced antitumor activity than single-agent blockade. We performed a single-arm study of pertuzumab, a monoclonal antibody that inhibits HER2 dimerization, and erlotinib in relapsed non-small cell lung cancer (NSCLC).
Patients received pertuzumab (840-mg loading dose and 420-mg maintenance intravenously every 3 weeks) and erlotinib (150-mg or 100-mg dose orally, daily). The primary endpoint was response rate (RR) by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) at day 56 in all patients and those with EGFR wild-type tumors.
Of 41 patients, 28 (68.3%) experienced treatment-related grade ≥3 adverse events, including pneumatosis intestinalis (3 patients), resulting in early cessation of enrollment. Tissue samples from 32 patients showed mutated EGFR status in 9 of 41 (22%) and wild-type EGFR in 23 of 41 (56%). The FDG-PET RR for patients with assessments at day 56 was 19.5% in all patients (n = 41) and 8.7% in patients with wild-type EGFR NSCLC (n = 23). Investigator-assessed computed tomography RR at day 56 was 12.2%.
FDG-PET suggests that pertuzumab plus erlotinib is an active combination, but combination therapy was poorly tolerated, which limits its clinical applicability. More research is warranted to identify drug combinations that disrupt HER receptor signaling but that exhibit improved tolerability profiles.
Keratoconus is a common complex corneal ectasia that can lead to severe visual impairment. Although a genetic component is well recognized, the genetic risk factors for keratoconus are yet to be fully elucidated. A recent genome-wide association study (GWAS) by Li et al. identified 15 potentially associated single nucleotide polymorphisms (SNPs). Here, we aimed to replicate these associations, and conduct a meta-analysis of the current and previous studies.
We genotyped the 15 reported associated SNPs in 524 Australian Caucasian cases with keratoconus and 2761 controls. Association analysis was conducted in PLINK. A meta-analysis of this study with the adjusted P values of the previously published GWAS was conducted using the method of Fisher to combine P values.
Our Australian cohort showed association (P < 0.003) at SNPs near RAB3GAP1, KCND3, IMMPL2, and in a gene desert on chromosome 13q33.3, providing evidence of replication of the published results. The meta-analysis showed SNP rs4954218 near RAB3GAP1 gene was associated significantly with keratoconus, with P = 9.26 × 10−9 passing the genome-wide significance level.
Although the mechanism of disease association is yet to be determined, SNP rs4954218 is associated consistently with keratoconus and likely tags a functional variant that contributes to disease susceptibility.
We describe the replication of published findings from a genome-wide association study of keratoconus. We show for the first time, to our knowledge, that SNPs near RAB3GAP1 are associated with keratoconus at genome-wide significance, and also provide further supportive evidence for association at other reported loci.
keratoconus; cornea; genetics; genome-wide association study; meta-analysis
In recent years, increasing evidence has emerged demonstrating that high-dose ascorbate bears cytotoxic effects on cancer cells in vitro and in vivo, making ascorbate a pro-oxidative drug that catalyzes hydrogen peroxide production in tissues instead of acting as a radical scavenger. This anticancer effect of ascorbate is hypoxia-inducible factor-1α- and O2-dependent. However, whether the intracellular mechanisms governing this effect are modulated by epigenetic phenomena remains unknown. We treated human melanoma cells with physiological (200 μM) or pharmacological (8 mM) ascorbate for 1 h to record the impact on DNA methyltransferase (DNMT)-activity, histone deacetylases (HDACs), and microRNA (miRNA) expression after 12 h. The results were analyzed with the MIRUMIR online tool that estimates the power of miRNA to serve as potential biomarkers to predict survival of cancer patients. FACS cell-cycle analyses showed that 8 mM ascorbate shifted BLM melanoma cells toward the sub-G1 fraction starting at 12 h after an initial primary G2/M arrest, indicative for secondary apoptosis induction. In pharmacological doses, ascorbate inhibited the DNMT activity in nuclear extracts of MeWo and BLM melanoma cells, but did not inhibit human HDAC enzymes of classes I, II, and IV. The expression of 151 miRNAs was altered 12 h after ascorbate treatment of BLM cells in physiological or pharmacological doses. Pharmacological doses up-regulated 32 miRNAs (≥4-fold) mainly involved in tumor suppression and drug resistance in our preliminary miRNA screening array. The most prominently up-regulated miRNAs correlated with a significantly increased overall survival of breast cancer or nasopharyngeal carcinoma patients of the MIRUMIR database with high expression of the respective miRNA. Our results suggest a possible epigenetic signature of pharmacological doses of ascorbate in human melanoma cells and support further pre-clinical and possibly even clinical evaluation of ascorbate for melanoma therapy.
ascorbate; vitamin C; cancer; melanoma; epigenetics; microRNA; HDAC; DNMT
In conducting genome-wide association studies (GWAS), analytical approaches leveraging biological information may further understanding of the pathophysiology of clinical traits. To discover novel associations with estimated glomerular filtration rate (eGFR), a measure of kidney function, we developed a strategy for integrating prior biological knowledge into the existing GWAS data for eGFR from the CKDGen Consortium. Our strategy focuses on single nucleotide polymorphism (SNPs) in genes that are connected by functional evidence, determined by literature mining and gene ontology (GO) hierarchies, to genes near previously validated eGFR associations. It then requires association thresholds consistent with multiple testing, and finally evaluates novel candidates by independent replication. Among the samples of European ancestry, we identified a genome-wide significant SNP in FBXL20 (P = 5.6 × 10−9) in meta-analysis of all available data, and additional SNPs at the INHBC, LRP2, PLEKHA1, SLC3A2 and SLC7A6 genes meeting multiple-testing corrected significance for replication and overall P-values of 4.5 × 10−4–2.2 × 10−7. Neither the novel PLEKHA1 nor FBXL20 associations, both further supported by association with eGFR among African Americans and with transcript abundance, would have been implicated by eGFR candidate gene approaches. LRP2, encoding the megalin receptor, was identified through connection with the previously known eGFR gene DAB2 and extends understanding of the megalin system in kidney function. These findings highlight integration of existing genome-wide association data with independent biological knowledge to uncover novel candidate eGFR associations, including candidates lacking known connections to kidney-specific pathways. The strategy may also be applicable to other clinical phenotypes, although more testing will be needed to assess its potential for discovery in general.
Concurrent chemoradiotherapy (CCRT) has become the standard of care for patients with unresectable stage III non–small cell lung cancer (NSCLC). The comparative merits of two widely used regimens: carboplatin/paclitaxel (PC) and cisplatin/etoposide (PE), each with concurrent radiotherapy, remain largely undefined. Records for consecutive patients with stage III NSCLC treated with PC or PE and ≥60 Gy chest radiotherapy between 2000 and 2011 were reviewed for outcomes and toxicity. Survival was estimated using the Kaplan–Meier method and Cox modeling with the Wald test. Comparison across groups was done using the student's t and chi-squared tests. Seventy-five (PC: 44, PE: 31) patients were analyzed. PC patients were older (median 71 vs. 63 years; P = 0.0006). Other characteristics were comparable between groups. With PE, there was significantly increased grade ≥3 neutropenia (39% vs. 14%, P = 0.024) and thrombocytopenia (10% vs. 0%, P = 0.039). Radiation pneumonitis was more common with PC (66% vs. 38%, P = 0.033). Five treatment-related deaths occurred (PC: 3 vs. PE: 2, P = 1.000). With a median follow-up of 51.6 months, there were no significant differences in relapse-free survival (median PC 12.0 vs. PE 11.5 months, P = 0.700) or overall survival (median PC 20.7 vs. PE 13.7 months; P = 0.989). In multivariate analyses, no factors predicted for improved survival for either regimen. PC was more likely to be used in elderly patients. Despite this, PC resulted in significantly less hematological toxicity but achieved similar survival outcomes as PE. PC is an acceptable CCRT regimen, especially in older patients with multiple comorbidities.
Carboplatin/paclitaxel; cisplatin/etoposide; concurrent chemoradiotherapy; locally advanced; non–small cell lung cancer; stage III
Glaucoma is a major cause of blindness in the world. Recent genome-wide association studies (GWAS) have identified common genetic variants for glaucoma, but still a significant heritability gap remains. We hypothesized that copy number variants (CNVs) might influence part of the susceptibility to glaucoma or its related quantitative endophenotypes.
This study examined the association between CNVs and intraocular pressure (IOP), the major modifiable risk factor for primary open-angle glaucoma (POAG), in three population panels of European ancestry: the TwinsUK cohort (n = 1047), the Australian Twin Eye Study (n = 561), and the Wellcome Trust Case-Control Consortium 2 (WTCCC2)/Blue Mountains Eye Study (BMES) (n = 1660). We also used PCR-based assays to investigate a locus of interest that we found associated with IOP in a POAG case–control panel of European ancestry from London, United Kingdom.
We identified associations between IOP and two CNV regions in the TwinsUK cohort: 5q21.2 (P = 0.003) overlapping the gene RAB9BP1 and 12p13.3 (P = 0.03) overlapping the genes SLC2A14 and SLC2A3. The Australian Twin Eye Study and BMES both replicated the 5q21.2 CNV association and direction of effect (P = 0.001 and P = 0.02, respectively). A meta-analysis across all the cohorts showed that presence of a copy number change at this locus increased IOP by 1.56 mm Hg (P = 1.24 × 10−6). In the case–control study, the 5q21.2 CNV locus did not show association with high-pressure (≥21 mm Hg) POAG cases.
The 5q21.2 CNV locus could represent a novel locus controlling IOP. Interestingly, this IOP locus is located in close vicinity to the previously widely replicated GLC1G linkage locus for glaucoma, for which subsequent studies have not reached consensus on the causal gene.
Copy number variation at chromosome 5q21.2 is associated with intraocular pressure.
copy number variation; intraocular pressure; 5q21.2
Refractive error is the most common eye disorder worldwide, and a prominent cause of blindness. Myopia affects over 30% of Western populations, and up to 80% of Asians. The CREAM consortium conducted genome-wide meta-analyses including 37,382 individuals from 27 studies of European ancestry, and 8,376 from 5 Asian cohorts. We identified 16 new loci for refractive error in subjects of European ancestry, of which 8 were shared with Asians. Combined analysis revealed 8 additional loci. The new loci include genes with functions in neurotransmission (GRIA4), ion channels (KCNQ5), retinoic acid metabolism (RDH5), extracellular matrix remodeling (LAMA2, BMP2), and eye development (SIX6, PRSS56). We also confirmed previously reported associations with GJD2 and RASGRF1. Risk score analysis using associated SNPs showed a tenfold increased risk of myopia for subjects with the highest genetic load. Our results, accumulated across independent multi-ethnic studies, considerably advance understanding of mechanisms involved in refractive error and myopia.
Congenital cataract is the most common cause of treatable visual impairment in children worldwide. Mutations in many different genes lead to congenital cataract. Recently, mutations in the receptor tyrosine kinase gene, EPHA2, have been found to cause congenital cataract in six different families. Although these findings have established EPHA2 as a causative gene, the total contribution of mutations in this gene to congenital cataract is unknown. In this study, for the first time, a population-based approach was used to investigate the frequency of disease causing mutations in the EPHA2 gene in inherited cataract cases in South-Eastern Australia. A cohort of 84 familial congenital or juvenile cataract index cases was screened for mutations in the EPHA2 gene by direct sequencing. Novel changes were assessed for segregation with the disease within the family and in unrelated controls. Microsatellite marker analysis was performed to establish any relationship between families carrying the same mutation. We report a novel congenital cataract causing mutation c.1751C>T in the EPHA2 gene and the previously reported splice mutation c.2826-9G>A in two new families. Additionally, we report a rare variant rs139787163 potentially associated with increased susceptibility to cataract. Thus mutations in EPHA2 account for 4.7% of inherited cataract cases in South-Eastern Australia. Interestingly, the identified rare variant provides a link between congenital and age-related cataract.
Anemia is a frequent complication of Crohn’s disease (CD). The intestinal iron exporter ferroportin (FPN) is involved in both iron deficiency anemia and the anemia of chronic disease. To examine its role in CD, intestinal FPN expression was studied in subjects with and without CD.
Duodenal mucosal biopsies from 29 pediatric subjects with CD (n = 19) and without CD (n = 10) were obtained. FPN protein was measured using Western blot analysis and mRNA was assessed using quantitative real-time polymerase chain reaction (PCR).
Intestinal FPN protein was higher in anemic CD subjects than in nonanemic CD subjects (P = 0.01), while FPN mRNA levels were not different (P = 0.66). In nonanemic CD subjects, erythrocyte sedimentation rate (ESR) (P = 0.04), C-reactive protein (CRP) (P = 0.03), and interleukin-6 (IL-6) (P = 0.01) levels were elevated compared to controls. Nonanemic CD subjects had a lower median FPN protein than nonanemic controls, although it did not reach statistical significance (P = 0.07). Median FPN mRNA was similar between groups (P = 0.71). Although no correlation between FPN protein and IL-6 was noted, there was a strong negative correlation between serum iron and IL-6, both in subjects with CD (r = −0.88, P < 0.0001) and those without anemia (r = −0.58, P = 0.02).
Intestinal FPN protein is upregulated in anemic CD subjects, suggesting that iron deficiency or anemia is the driving force regulating FPN levels. A transporter distinct from FPN appears to be involved in the hypoferremia associated with the inflammatory process of CD.
Crohn’s disease; anemia; ferroportin; iron