Urinary extracellular vesicles miRNA-A new era of prostate cancer biomarkers.

Prostate cancer is the second most common male cancer worldwide showing the highest rates of incidence in Western Europe. Although the measurement of serum prostate-specific antigen levels is the current gold standard in PCa diagnosis, PSA-based screening is not considered a reliable diagnosis and prognosis tool due to its lower sensitivity and poor predictive score which lead to a 22%-43% overdiagnosis, unnecessary biopsies, and over-treatment. These major limitations along with the heterogeneous nature of the disease have made PCa a very unappreciative subject for diagnostics, resulting in poor patient management; thus, it urges to identify and validate new reliable PCa biomarkers that can provide accurate information in regard to disease diagnosis and prognosis. Researchers have explored the analysis of microRNAs (miRNAs), messenger RNAs (mRNAs), small proteins, genomic rearrangements, and gene expression in body fluids and non-solid tissues in search of lesser invasive yet efficient PCa biomarkers. Although the presence of miRNAs in body fluids like blood, urine, and saliva initially sparked great interest among the scientific community; their potential use as liquid biopsy biomarkers in PCa is still at a very nascent stage with respect to other well-established diagnostics and prognosis tools. Up to date, numerous studies have been conducted in search of PCa miRNA-based biomarkers in whole blood or blood serum; however, only a few studies have investigated their presence in urine samples of which less than two tens involve the detection of miRNAs in extracellular vesicles isolated from urine. In addition, there exists some discrepancy around the identification of miRNAs in PCa urine samples due to the diversity of the urine fractions that can be targeted for analysis such as urine circulating cells, cell-free fractions, and exosomes. In this review, we aim to discuss research output from the most recent studies involving the analysis of urinary EVs for the identification of miRNA-based PCa-specific biomarkers.

Genetic susceptibility to telomere shortening through the rs2293607 polymorphism is associated with a greater risk of alcohol use disorder.

Telomere shortening is usually considered a biomarker of ageing. Harmful alcohol use promotes accelerated biological ageing and alcohol use disorders (AUDs) are associated with short telomere length (TL). This study was conducted to examine the relationship of TL to AUD and determine whether single nucleotide polymorphisms (SNPs) in TERC and TERT modulate this association. For this purpose, we genotyped TERC SNPs rs2293607, rs12696304, and rs16847897 and TERT SNPs rs2735940, rs2736100, and rs2736098 in 308 male patients with AUD and 255 sex-matched healthy controls and measured TL in a subset of 99 patients and 99 controls paired by age and smoking status. Our results showed that the mean TL was shorter in patients with AUD than in controls. The area under the ROC curve was 0.70 (P < 0.001). The GG genotype of TERC rs2293607 was more common among patients with AUD than among controls (9.8% vs. 5.1%; P = 0.038). No difference was found for the other SNPs. Carriers of the GG genotype of rs2293607 had shorter telomeres than did allele A carriers. In conclusion, patients with AUD had shorter telomeres. Genetic susceptibility to telomere shortening through the rs2293607 SNP is associated with a greater risk of AUD.

MiR-21 Is Required for the Epithelial-Mesenchymal Transition in MDA-MB-231 Breast Cancer Cells.

Breast cancer (BCa) is one of the leading health problems among women. Although significant achievements have led to advanced therapeutic success with targeted therapy options, more efforts are required for different subtypes of tumors and according to genomic, transcriptomic, and proteomic alterations. This study underlines the role of microRNA-21 (miR-21) in metastatic MDA-MB-231 breast cancer cells. Following the knockout of miR-21 from MDA-MB-231 cells, which have the highest miR-21 expression levels compared to MCF-7 and SK-BR-3 BCa cells, a decrease in epithelial-mesenchymal transition (EMT) via downregulation of mesenchymal markers was observed. Wnt-11 was a critical target for miR-21, and the Wnt-11 related signaling axis was altered in the stable miR-21 knockout cells. miR-21 expression was associated with a significant increase in mesenchymal markers in MDA-MB-231 BCa cells. Furthermore, the release of extracellular vesicles (EVs) was significantly reduced in the miR-21 KO cells, alongside a significant reduction in relative miR-21 export in EV cargo, compared with control cells. We conclude that miR-21 is a leading factor involved in mesenchymal transition in MDA-MB-231 BCa. Future therapeutic strategies could focus on its role in the treatment of metastatic breast cancer.

FRMD6 has tumor suppressor functions in prostate cancer.

Available tools for prostate cancer (PC) prognosis are suboptimal but may be improved by better knowledge about genes driving tumor aggressiveness. Here, we identified FRMD6 (FERM domain-containing protein 6) as an aberrantly hypermethylated and significantly downregulated gene in PC. Low FRMD6 expression was associated with postoperative biochemical recurrence in two large PC patient cohorts. In overexpression and CRISPR/Cas9 knockout experiments in PC cell lines, FRMD6 inhibited viability, proliferation, cell cycle progression, colony formation, 3D spheroid growth, and tumor xenograft growth in mice. Transcriptomic, proteomic, and phospho-proteomic profiling revealed enrichment of Hippo/YAP and c-MYC signaling upon FRMD6 knockout. Connectivity Map analysis and drug repurposing experiments identified pyroxamide as a new potential therapy for FRMD6 deficient PC cells. Finally, we established orthotropic Frmd6 and Pten, or Pten only (control) knockout in the ROSA26 mouse prostate. After 12 weeks, Frmd6/Pten double knockouts presented high-grade prostatic intraepithelial neoplasia (HG-PIN) and hyperproliferation, while Pten single-knockouts developed only regular PIN lesions and displayed lower proliferation. In conclusion, FRMD6 was identified as a novel tumor suppressor gene and prognostic biomarker candidate in PC.

Germline genetic variation in prostate susceptibility does not predict outcomes in the chemoprevention trials PCPT and SELECT.

BACKGROUND: The development of prostate cancer can be influenced by genetic and environmental factors. Numerous germline SNPs influence prostate cancer susceptibility. The functional pathways in which these SNPs increase prostate cancer susceptibility are unknown. Finasteride is currently not being used routinely as a chemoprevention agent but the long term outcomes of the PCPT trial are awaited. The outcomes of the SELECT trial have not recommended the use of chemoprevention in preventing prostate cancer. This study investigated whether germline risk SNPs could be used to predict outcomes in the PCPT and SELECT trial. METHODS: Genotyping was performed in European men entered into the PCPT trial (n = 2434) and SELECT (n = 4885). Next generation genotyping was performed using Affymetrix® Eureka™ Genotyping protocols. Logistic regression models were used to test the association of risk scores and the outcomes in the PCPT and SELECT trials. RESULTS: Of the 100 SNPs, 98 designed successfully and genotyping was validated for samples genotyped on other platforms. A number of SNPs predicted for aggressive disease in both trials. Men with a higher polygenic score are more likely to develop prostate cancer in both trials, but the score did not predict for other outcomes in the trial. CONCLUSION: Men with a higher polygenic risk score are more likely to develop prostate cancer. There were no interactions of these germline risk SNPs and the chemoprevention agents in the SELECT and PCPT trials.

Genetic study in patients operated dentally and anesthetized with articaine-epinephrine.

Aims: In this study we wanted to figure out if there was a correlation between OPRM1 N40D, TRPV1 I316M, TRPV1 I585V, NOS3 -786T>C and IL6 -174C>G polymorphisms and the response to locally applied articaine-epinephrine anesthetic. Methods: In this observational study, 114 oral cell samples of patients anesthetized with articaine-epinephrine (54 from men 60 from women), were collected from dental centers in Madrid (Spain). High molecular weight DNA was obtained from oral mucosa cells. The analysis of OPRM1 N40D (rs1799971), TRPV1 I316M (rs222747), TRPV1 I585V (rs8065080) and IL6 -174C>G polymorphism was performed through real-time PCR allelic discrimination using TaqMan probes. Polymorphism NOS3 -786T> C (rs2070744) was analyzed using RFLP-PCR. Results: The studied polymorphisms are involved neither in the response to the anesthetic, nor in the intensity of perceived dental pain. However, in a subset of female patients we found that TRPV1 I316M was associated with a delayed onset of anesthesia. Conclusions: There is no association among these polymorphisms and the time elapsed between the application of the anesthetic and the onset of its effect.

Correction: Rare germline variants in DNA repair genes and the angiogenesis pathway predispose prostate cancer patients to develop metastatic disease.

This article was originally published under the standard License to Publish, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the paper have been modified accordingly.

Germline DNA Repair Gene Mutations in Young-onset Prostate Cancer Cases in the UK: Evidence for a More Extensive Genetic Panel.

BACKGROUND: Rare germline mutations in DNA repair genes are associated with prostate cancer (PCa) predisposition and prognosis. OBJECTIVE: To quantify the frequency of germline DNA repair gene mutations in UK PCa cases and controls, in order to more comprehensively evaluate the contribution of individual genes to overall PCa risk and likelihood of aggressive disease. DESIGN, SETTING, AND PARTICIPANTS: We sequenced 167 DNA repair and eight PCa candidate genes in a UK-based cohort of 1281 young-onset PCa cases (diagnosed at ≤60yr) and 1160 selected controls. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Gene-level SKAT-O and gene-set adaptive combination of p values (ADA) analyses were performed separately for cases versus controls, and aggressive (Gleason score ≥8, n=201) versus nonaggressive (Gleason score ≤7, n=1048) cases. RESULTS AND LIMITATIONS: We identified 233 unique protein truncating variants (PTVs) with minor allele frequency <0.5% in controls in 97 genes. The total proportion of PTV carriers was higher in cases than in controls (15% vs 12%, odds ratio [OR]=1.29, 95% confidence interval [CI] 1.01-1.64, p=0.036). Gene-level analyses selected NBN (pSKAT-O=2.4×10-4) for overall risk and XPC (pSKAT-O=1.6×10-4) for aggressive disease, both at candidate-level significance (p<3.1×10-4 and p<3.4×10-4, respectively). Gene-set analysis identified a subset of 20 genes associated with increased PCa risk (OR=3.2, 95% CI 2.1-4.8, pADA=4.1×10-3) and four genes that increased risk of aggressive disease (OR=11.2, 95% CI 4.6-27.7, pADA=5.6×10-3), three of which overlap the predisposition gene set. CONCLUSIONS: The union of the gene-level and gene-set-level analyses identified 23 unique DNA repair genes associated with PCa predisposition or risk of aggressive disease. These findings will help facilitate the development of a PCa-specific sequencing panel with both predictive and prognostic potential. PATIENT SUMMARY: This large sequencing study assessed the rate of inherited DNA repair gene mutations between prostate cancer patients and disease-free men. A panel of 23 genes was identified, which may improve risk prediction or treatment pathways in future clinical practice.

Author Correction: Association analyses of more than 140,000 men identify 63 new prostate cancer susceptibility loci.

In the version of this article initially published, the name of author Manuela Gago-Dominguez was misspelled as Manuela Gago Dominguez. The error has been corrected in the HTML and PDF version of the article.

Rare germline variants in DNA repair genes and the angiogenesis pathway predispose prostate cancer patients to develop metastatic disease.

BACKGROUND: Prostate cancer (PrCa) demonstrates a heterogeneous clinical presentation ranging from largely indolent to lethal. We sought to identify a signature of rare inherited variants that distinguishes between these two extreme phenotypes. METHODS: We sequenced germline whole exomes from 139 aggressive (metastatic, age of diagnosis < 60) and 141 non-aggressive (low clinical grade, age of diagnosis ≥60) PrCa cases. We conducted rare variant association analyses at gene and gene set levels using SKAT and Bayesian risk index techniques. GO term enrichment analysis was performed for genes with the highest differential burden of rare disruptive variants. RESULTS: Protein truncating variants (PTVs) in specific DNA repair genes were significantly overrepresented among patients with the aggressive phenotype, with BRCA2, ATM and NBN the most frequently mutated genes. Differential burden of rare variants was identified between metastatic and non-aggressive cases for several genes implicated in angiogenesis, conferring both deleterious and protective effects. CONCLUSIONS: Inherited PTVs in several DNA repair genes distinguish aggressive from non-aggressive PrCa cases. Furthermore, inherited variants in genes with roles in angiogenesis may be potential predictors for risk of metastases. If validated in a larger dataset, these findings have potential for future clinical application.

Association analyses of more than 140,000 men identify 63 new prostate cancer susceptibility loci.

Genome-wide association studies (GWAS) and fine-mapping efforts to date have identified more than 100 prostate cancer (PrCa)-susceptibility loci. We meta-analyzed genotype data from a custom high-density array of 46,939 PrCa cases and 27,910 controls of European ancestry with previously genotyped data of 32,255 PrCa cases and 33,202 controls of European ancestry. Our analysis identified 62 novel loci associated (P < 5.0 × 10-8) with PrCa and one locus significantly associated with early-onset PrCa (≤55 years). Our findings include missense variants rs1800057 (odds ratio (OR) = 1.16; P = 8.2 × 10-9; G>C, p.Pro1054Arg) in ATM and rs2066827 (OR = 1.06; P = 2.3 × 10-9; T>G, p.Val109Gly) in CDKN1B. The combination of all loci captured 28.4% of the PrCa familial relative risk, and a polygenic risk score conferred an elevated PrCa risk for men in the ninetieth to ninety-ninth percentiles (relative risk = 2.69; 95% confidence interval (CI): 2.55-2.82) and first percentile (relative risk = 5.71; 95% CI: 5.04-6.48) risk stratum compared with the population average. These findings improve risk prediction, enhance fine-mapping, and provide insight into the underlying biology of PrCa1.

Fine-mapping of prostate cancer susceptibility loci in a large meta-analysis identifies candidate causal variants.

Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified; the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling.

Pharmacokinetic drug evaluation of vorapaxar for secondary prevention after acute coronary syndrome.

INTRODUCTION: Vorapaxar is the first protease-activated receptor-1 inhibitor approved for clinical use. Its main indication is the reduction in thrombotic cardiovascular events in patients with previous myocardial infarction or symptomatic peripheral artery disease. Areas covered: This article reviews the pharmacokinetics of vorapaxar and its potential use in secondary prevention after an acute coronary syndrome. Expert opinion: Vorapaxar inhibits platelet aggregation mediated by thrombin. This effect is carried out without affecting to coagulation parameters and bleeding times. This drug has showed a significant reduction of cardiovascular events in patients with chronic atherosclerosis but not during the admission for an acute coronary syndrome. The rate of major bleeding found in patients treated with vorapaxar in randomized trials was consistently higher than placebo in most of the analyzed subgroups. For this reason, cautious evaluation of risk-benefit profiles should be required before prescribing this drug.

A Single Nucleotide Polymorphism in the RASGRF2 Gene Is Associated with Alcoholic Liver Cirrhosis in Men.

BACKGROUND: Genetic polymorphisms in the RAS gene family are associated with different diseases, which may include alcohol-related disorders. Previous studies showed an association of the allelic variant rs26907 in RASGRF2 gene with higher alcohol intake. Additionally, the rs61764370 polymorphism in the KRAS gene is located in a binding site for the let-7 micro-RNA family, which is potentially involved in alcohol-induced inflammation. Therefore, this study was designed to explore the association between these two polymorphisms and susceptibility to alcoholism or alcoholic liver disease (ALD). METHODS: We enrolled 301 male alcoholic patients and 156 healthy male volunteers in this study. Polymorphisms were genotyped by using TaqMan® PCR assays for allelic discrimination. Allelic and genotypic frequencies were compared between the two groups. Logistic regression analysis was performed to analyze the inheritance model. RESULTS: The A allele of the RASGRF2 polymorphism (rs26907) was significantly more prevalent among alcoholic patients with cirrhosis (23.2%) compared to alcoholic patients without ALD (14.2%). This difference remained significant in the group of patients with alcohol dependence (28.8% vs. 14.3%) but not in those with alcohol abuse (15.1% vs. 14.4%). Multivariable logistic regression analysis showed that the A allele of this polymorphism (AA or GA genotype) was associated with alcoholic cirrhosis both in the total group of alcoholics (odds ratio [OR]: 2.33, 95% confidence interval [CI]: 1.32-4.11; P = 0.002) and in the group of patients with alcohol dependence (OR: 3.1, 95% CI: 1.50-6.20; P = 0.001). Allelic distributions of the KRAS polymorphism (rs61764370) did not differ between the groups. CONCLUSIONS: To our knowledge, this genetic association study represents the first to show an association of the RASGRF2 G>A (rs26907) polymorphism with ALD in men, particularly in the subgroup of patients with AD. The findings suggest the potential relevance of the RAS gene family in alcoholism and ALD.

Association of Lysyl Oxidase-Like 1 Gene Polymorphisms in Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma in a Spanish Population.

PURPOSE: To evaluate the association of the lysyl oxidase-like 1 (LOXL1) single nucleotide polymorphisms (SNPs) in a Spanish population with pseudoexfoliation syndrome (XFS) and pseudoexfoliation glaucoma (XFG). MATERIALS AND METHODS: The present case-control study included 100 Spanish patients (60 patients with XFS and 40 patients with XFG) and 90 control subjects. Genotypes of the three single nucleotide polymorphisms of LOXL1 (rs1048661, rs3825942, and rs2165241) were analyzed with direct sequencing. RESULTS: The G allele and the GG genotype of SNP rs3825942 were detected at a statistically higher frequency in pseudoexfoliation patients than in control subjects (p = 3.36 × 10(-5), OR = 5.71, 95% CI: 2.30-14.18; p = 3.38 × 10(-5), OR = 6.91, 95% CI: 2.51-19.03 respectively). The T allele and the TT genotype of SNP rs2165241 presented at significantly higher frequencies in pseudoexfoliation patients than in controls (p = 2.50 × 10(-4), OR = 2.18, 95% CI: 1.43-3.33; p = 1.21 × 10(-2), OR = 2.13, 95% CI: 1.75-3.85 respectively). No significant association between XFS/XFG and the rs1048661 was observed. The GGT haplotype composed of all three risk alleles was determined to be significantly associated with pseudoexfoliation. The genotypic and allelic distributions of the three SNPs were similar between XFS and XFG. CONCLUSIONS: This is the first study associating two SNPs of LOXL1 (rs3825942 and rs2165241) and XFS/XFG in a Spanish population, confirming findings in patients from Europe. However rs1048661 SNP did not show an association with XFS.

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans.

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same region.

Early-onset type 2 diabetes mellitus is associated to HNF4A T130I polymorphism in families of central Spain.

PURPOSE: Type 2 diabetes mellitus (type 2 DM) and maturity-onset diabetes of the young present some similar clinical and biochemical characteristics that make them difficult to differentiate. Currently, the polymorphism T130I (rs1800961) in the HNF4A (hepatocyte nuclear factor 4A) gene has been described as a risk factor to type 2 DM and shows an autosomal dominant inheritance pattern associated to ß-cell function decrease. The aim of the present work was to characterize the phenotypic profile of the T130I carrier and noncarrier relatives included in 3 unrelated families. METHODS: We studied GCK, HNF1A, and HNF4A genes by polymerase chain reaction and sequencing in 3 unrelated subjects from Valladolid, Spain, in which maturity-onset diabetes of the young was suspected. We collected genetic, clinical, and biochemical data from these subjects and their relatives in order to check the presence of the T130I polymorphism. RESULTS: The heterozygous T130I mutation was the unique functional gene variation that could explain diabetes phenotype. We observed significant differences in glucose metabolism, lipid profile, and Homeostasis Model Assessment index when we compared T130I mutation carriers and noncarriers. Diabetes diagnosed in T130I mutation carriers was related to stressful situations in an earlier age and tightly associated with gestational diabetes. Fasting plasma glucose and HbA(1c) levels increased with age in all carriers (r = 0.69 and r = 0.66, P < 0.01), respectively. CONCLUSIONS: Our study supports the T130I variant in HNF4A as a major susceptibility genotype associated with early-onset type 2 DM. Healthy carriers of this mutation require a stricter control in the population of central Spain.

Cognitive outcome and gamma noise power unrelated to neuregulin 1 and 3 variation in schizophrenia.

BACKGROUND: Neuregulins are a family of signalling proteins that orchestrate a broad range of cellular responses. Four genes encoding Neuregulins 1-4 have been identified so far in vertebrates. Among them, Neuregulin 1 and Neuregulin 3 have been reported to contribute to an increased risk for developing schizophrenia. We hypothesized that three specific variants of these genes (rs6994992 and rs3924999 for Neuregulin 1 and rs10748842 for Neuregulin 3) that have been related to this illness may modify information processing capacity in the cortex, which would be reflected in electrophysiological parameters (P3b amplitude or gamma noise power) and/or cognitive performance. METHODS: We obtained DNA from 31 patients with schizophrenia and 23 healthy controls and analyzed NRG1 rs6994992, NRG1 rs3924999 and NRG3 rs10748842 promoter polymorphisms by allelic discrimination with real-time polymerase chain reaction (PCR). We compared cognitive outcome, P300 amplitude parameters and an electroencephalographic measure of noise power in the gamma band between the groups dichotomized according to genotype. RESULTS: Contrary to our hypothesis, we could not detect any significant influence of variation in Neuregulin 1/Neuregulin 3 polymorphisms on cognitive performance or electrophysiological parameters of patients with schizophrenia. CONCLUSIONS: Despite our findings, we cannot discard that other genetic variants and, more likely, interactions between those variants and with genetic variation related to different pathways may still influence cerebral processing in schizophrenia.

Telomere length shows no association with BRCA1 and BRCA2 mutation status.

This study aimed to determine whether telomere length (TL) is a marker of cancer risk or genetic status amongst two cohorts of BRCA1 and BRCA2 mutation carriers and controls. The first group was a prospective set of 665 male BRCA1/2 mutation carriers and controls (mean age 53 years), all healthy at time of enrollment and blood donation, 21 of whom have developed prostate cancer whilst on study. The second group consisted of 283 female BRCA1/2 mutation carriers and controls (mean age 48 years), half of whom had been diagnosed with breast cancer prior to enrollment. TL was quantified by qPCR from DNA extracted from peripheral blood lymphocytes. Weighted and unweighted Cox regressions and linear regression analyses were used to assess whether TL was associated with BRCA1/2 mutation status or cancer risk. We found no evidence for association between developing cancer or being a BRCA1 or BRCA2 mutation carrier and telomere length. It is the first study investigating TL in a cohort of genetically predisposed males and although TL and BRCA status was previously studied in females our results don't support the previous finding of association between hereditary breast cancer and shorter TL.

Predictive value of VEGF A and VEGFR2 polymorphisms in the response to intravitreal ranibizumab treatment for wet AMD.

BACKGROUND: To determine whether gene polymorphisms of the vascular endothelial growth factor A (VEGF A) and its receptor (VEGFR) influence the response to a variable-dosing treatment regimen with ranibizumab for age-related macular degeneration. METHODS: This prospective cohort study included 94 patients (94 eyes) with exudative age-related macular degeneration (AMD) treated with ranibizumab. Patients underwent a 1-year treatment as in the Study of Ranibizumab in Patients with Subfoveal Choroidal Neovascularization Secondary to Age-Related Macular Degeneration (SUSTAIN). Injections were administered monthly during 3 months to all the patients diagnosed of neovascular AMD; reinjections were made when a patient lost 5 letters on the Early Treatment Diabetic Retinopathy Study chart or gained 100 µm in central subfield retinal thickness measured by OCT. Genotypes (VEGF A (rs 699947, rs833061) and VEGFR (rs 2071559)) were analyzed using TaqMan probes. Best-corrected visual acuity (BCVA), subjective improvement, and macular thickness measured with OCT values were compared with VEGF A and VEGFR genotypes. Multiple regression analysis was used to assess the statistical significance. RESULTS: We found statistically significant differences in allelic distribution of VEGF A rs833061 polymorphism in relation with the response to intravitreal ranibizumab regarding to visual acuity improvement [p = 0,.34; OR: 1.619 (1.098-2.386)]. Patients carrying "protector" genotype CC had higher probability of best corrected visual acuity improvement. When we analyzed VEGF A rs699947 polymorphism we found that patients expressing AA genotype had a higher chance of increasing their best corrected visual acuity [p:0,022; OR 1,532 (1,015-2,313)]. We did not find statistically significant differences reagarding VEGFR rs2071559 polymorphism and treatment response. CONCLUSIONS: Polymorphisms of VEGF A seem to influence the different response to antiangiogenic treatment in patients with AMD in our population, although further investigation is needed to know the mechanisms of this relationship.