ABSTRACT
Clopidogrel is widely used worldwide as an antiplatelet therapy in patients with acute coronary disease. Genetic factors influence interindividual variability in response. Some studies have explored the polygenic contributions in the drug response, generating pharmacogenomic risk scores (PgxPRS). Importantly, these factors are less explored in underrepresented populations, such as Latin-American countries. Identifying patients at risk of high-on-treatment platelet reactivity (HTPR) is highly valuable in translational medicine. In this study we used a custom next-generation sequencing (NGS) panel composed of 91 single nucleotide polymorphisms (SNPs) and 28 genes related to clopidogrel metabolism, to analyze 70 patients with platelet reactivity values, assessed through closure time (CT). Our results demonstrated the association of SNPs with HTPR and non-HTPR, revealing the strongest associations with rs2286823 (OR: 5,0; 95% CI: 1,02-24,48; p: 0,03), rs2032582 (OR: 4,41; 95% CI: 1,20-16,12; p: 0,019), and rs1045642 (OR: 3,38; 95% CI: 0,96-11,9; p: 0,05). Bivariate regression analysis demonstrated the significant association of several SNPs with the CT value, a "surrogate" biomarker of clopidogrel response. Exploratory results from the LASSO regression model showed a high discriminatory capacity between HTPR and non-HTPR patients (AUC: 0,955), and the generated PgxPRS demonstrated a significant negative association between the risk score, CT value, and the condition of HTPR and non-HTPR. To our knowledge, our study addresses for the first time the analysis of the polygenic contribution in platelet reactivity using NGS and establishes PgxPRS derived from the LASSO model. Our results demonstrate the polygenic implication of clopidogrel response and offer insights applicable to the translational medicine of antiplatelet therapy in an understudied population.
Subject(s)
Blood Platelets , Clopidogrel , High-Throughput Nucleotide Sequencing , Platelet Aggregation Inhibitors , Polymorphism, Single Nucleotide , Humans , Clopidogrel/therapeutic use , Clopidogrel/pharmacology , Male , High-Throughput Nucleotide Sequencing/methods , Female , Platelet Aggregation Inhibitors/therapeutic use , Platelet Aggregation Inhibitors/pharmacology , Middle Aged , Blood Platelets/drug effects , Blood Platelets/metabolism , Aged , Multifactorial Inheritance/genetics , Ticlopidine/analogs & derivatives , Ticlopidine/therapeutic use , Ticlopidine/pharmacologyABSTRACT
BACKGROUND: In Colombia and worldwide, breast cancer (BC) is the most frequently diagnosed neoplasia and the leading cause of death from cancer among women. Studies predominantly involve hereditary and familial cases, demonstrating a gap in the literature regarding the identification of germline mutations in unselected patients from Latin-America. Identification of pathogenic/likely pathogenic (P/LP) variants is important for shaping national genetic analysis policies, genetic counseling, and early detection strategies. The present study included 400 women with unselected breast cancer (BC), in whom we analyzed ten genes, using Whole Exome Sequencing (WES), know to confer risk for BC, with the aim of determining the genomic profile of previously unreported P/LP variants in the affected population. Additionally, Multiplex Ligation-dependent Probe Amplification (MLPA) was performed to identify Large Genomic Rearrangements (LGRs) in the BRCA1/2 genes. To ascertain the functional impact of a recurrent intronic variant (ATM c.5496 + 2_5496 + 5delTAAG), a minigene assay was conducted. RESULTS: We ascertained the frequency of P/LP germline variants in BRCA2 (2.5%), ATM (1.25%), BRCA1 (0.75%), PALB2 (0.50%), CHEK2 (0.50%), BARD1 (0.25%), and RAD51D (0.25%) genes in the population of study. P/LP variants account for 6% of the total population analyzed. No LGRs were detected in our study. We identified 1.75% of recurrent variants in BRCA2 and ATM genes. One of them corresponds to the ATM c.5496 + 2_5496 + 5delTAAG. Functional validation of this variant demonstrated a splicing alteration probably modifying the Pincer domain and subsequent protein structure. CONCLUSION: This study described for the first time the genomic profile of ten risk genes in Colombian women with unselected BC. Our findings underscore the significance of population-based research, advocating the consideration of molecular testing in all women with cancer.
Subject(s)
BRCA2 Protein , Breast Neoplasms , Genetic Predisposition to Disease , Germ-Line Mutation , Humans , Female , Germ-Line Mutation/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Breast Neoplasms/epidemiology , Colombia/epidemiology , Middle Aged , Adult , BRCA2 Protein/genetics , BRCA1 Protein/genetics , Exome Sequencing , Aged , Genetic Testing/methods , Ataxia Telangiectasia Mutated Proteins/geneticsABSTRACT
Purpose: Breast Cancer (BC) is the main female cancer diagnosed worldwide, and it has been described that few genes, such as BRCA1, have a high penetrance for this type of cancer. In this manuscript, we were interested in evaluating the effect of 3'UTR variants on BRCA1 expression. Patients and Methods: To accomplish this objective, Whole Exome Sequencing (WES) data of 400 patients with unselected BC was used to filter variants located in the region of interest of BRCA1 gene, finding two of them (c.*36C>G and c.*369_373del). miRGate and miRanda in silico tools were used to predict microRNA (miRNA) interaction. Results: The two variants (c.*36C>G, c.*369_373del) were predicted to affect miRNA interaction. After cloning of BRCA1 3'UTR into pMIR-Report vector, the construct was transfected into two BC cell lines (MDA-MB-231 and MCF-7), and the variant c.*36C>G evidenced overexpression of reporter gene luciferase, showing that the transcript was not being degraded by the miRNA in MDA-MB-231 cells. Conclusion: The variant seems to protect against Triple Negative BC probably due to the expression level of miRNA in this particular cell line (MDA-MB-231). This is consistent with the clinical history of the patients who harbor BC Hormone Receptors positive (HR+).
ABSTRACT
Resumen Introducción. La anemia perioperatoria es una complicación común de la cirugía cardiovascular. Pacientes con el alelo T del polimorfismo rs11549465 de HIF-1α podrían tener niveles alterados de hemoglobina y lactato antes, durante y después de la cirugía, en comparación con los del ancestral. Esto, por un aumento en la estabilidad de HIF-1α causado por este. Objetivo. Describir la frecuencia del alelo T en pacientes de cirugía cardiovascular programada y su relación con los niveles de hemoglobina y lactato. Materiales y métodos: Se aisló ADN de 84 pacientes de cirugía cardiovascular para genotipificación por secuenciación de Sanger y se recolectaron características demográficas y clínicas. Resultados. La frecuencia del alelo T fue 0.066 (IC95%: 0.037-0.114). No hubo diferencias significativas en los niveles de hemoglobina y lactato preoperatorios, intraoperatorios y posoperatorios entre pacientes con alelo T y aquellos con alelo ancestral. Conclusión. La frecuencia del alelo T fue menor que la esperada, de acuerdo con otros estudios en poblaciones similares de voluntarios sanos y no mostró diferencias significativas con algunas poblaciones asiáticas, ni con un grupo de pacientes con infarto agudo de miocardio. Parece que la genotipificación de rs11549465 en pacientes de cirugía cardiovascular no representó un método de estratificación de riesgo de anemia en este grupo.
Abstract Introduction: Perioperative anemia is a common complication of cardiovascular surgery. Patients who present the T allele of the HIF-1α rs11549465 polymorphism may have altered hemoglobin and lactate levels before, during and after surgery, compared to the wild-type allele, due to an increased stability of HIF-1α caused by this allele. Objective: To describe the frequency of the T allele in patients scheduled for cardiovascular surgery, and its relationship with hemoglobin and lactate levels. Materials and methods: DNA was isolated from 84 cardiovascular surgery patients for genotyping by Sanger sequencing. Demographic and clinical characteristics were collected. Results: The frequency of the T allele was 0.066 (95%CI: 0.0370.114). No significant differences were observed in preoperative, intraoperative, and postoperative hemoglobin and lactate levels between patients with the T allele and those with the wild-type allele. Conclusion: The frequency of the T allele is lower than expected according to other studies in healthy volunteers. No significant differences were observed in some Asian populations, nor in a group of acute myocardial infarction patients. Apparently, rs11549465 genotyping in cardiovascular surgery patients is not a valid risk stratification method for anemia in this group.
ABSTRACT
En esta edición de la Revista Colombiana de Cardiología, Jaramillo y colaboradores reportan el estudio de las frecuencias de un polimorfismo de inserción/deleción (I/D) en un elemento intrónico del gen codificante de la enzima convertidora de angiotensina (ECA) y su relación con el riesgo de enfermedad coronaria. La hipótesis de la influencia del alelo D en el riesgo de enfermedad cardiovascular se basa en una correlación observada entre la presencia de dicho alelo y los niveles elevados de ECA. Se piensa que éstos generarán mayores niveles de angiotensina II a partir de angiotensina I y degradarán bradiquinina, afectando el equilibrio hemodinámico y desencadenando complicaciones cardiacas y/o renales. El análisis de este polimorfismo se ve complicado por el hecho de que es considerado un locus de un carácter cuantitativo (quantitative trait locus) que modifica el nivel de expresión de ECA. Sin embargo, no se conoce el mecanismo molecular que explica la correlación entre la presencia del alelo D de ECA y los niveles elevados de ésta en el plasma. De hecho, se ha demostrado que hay al menos cuatro polimorfismos en el gen de ECA que pueden afectar su expresión y que, en sujetos de ascendencia europea, hay un desequilibrio de ligamiento muy alto entre el alelo D de ECA y algunos de estos elementos . Por el contrario, en familias de Nigeria (y posiblemente en otras poblaciones), no existe un desequilibrio de ligamiento tan alto y los niveles de ECA no muestran correlación significativa con el alelo D . Debido a la falta de conocimiento sobre los mecanismos de regulación de expresión del gen de ECA, es posible que el alelo D de ECA sólo se correlacione con la expresión de ECA en ciertas poblaciones (donde existe un desequilibrio de ligamiento con otros elementos con mayor efecto sobre la expresión del gen), hecho que podría explicar las inconsistencias que se observan en la relación entre el alelo D de ECA y el riesgo de enfermedad cardiovascular en diferentes poblaciones.