Association of FMO3 rs1736557 polymorphism with clopidogrel response in Chinese patients with coronary artery disease.

PURPOSE: Dual antiplatelet therapy with aspirin and clopidogrel is commonly used for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention to prevent stent thrombosis and ischemic events. However, some patients show high on-treatment platelet reactivity (HTPR) during clopidogrel therapy. Genetic factors such as loss-of-function variants of CYP2C19 are validated to increase the risk of HTPR. Flavin-containing monooxygenase 3 (FMO3) is reported to be associated with potency of platelet responsiveness and thrombosis. This study aimed to explore the association between FMO3 rs1736557 polymorphism and clopidogrel response. METHODS: Five hundred twenty-two Chinese CAD patients treated with dual antiplatelet therapy were recruited from Xiangya Hospital. After oral administration of 300 mg loading dose (LD) clopidogrel for 12-24 h or 75 mg daily maintenance dose (MD) clopidogrel for at least 5 days, the platelet reaction index (PRI) was determined by vasodilator-stimulated phosphoprotein-phosphorylation assay. FMO3 rs1736557, CYP2C19*2, and CYP2C19*3 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Mean PRI value was significantly higher in CYP2C19 poor metabolizers (PMs) and intermediate metabolizers (IMs) than the extensive metabolizers (EMs) (p < 0.001). In addition, FMO3 rs1736557 AA homozygotes showed significantly lower PRI as compared with carriers of the major rs1736557 G allele in the entire cohort and in the MD cohort (p = 0.011, p = 0.008, respectively). The risk of HTPR was decreased significantly in carriers of the rs1736557 A allele (AA vs GG: OR = 0.316, 95% CI: 0.137-0.726, p = 0.005; AA vs GA: OR = 0.249, 95% CI: 0.104-0.597, p = 0.001; AA vs GG+GA: OR = 0.294, 95% CI: 0.129-0.669, p = 0.002), and the association was observed mainly in patients carrying the CYP2C19 LOF allele and in those administered with MD. CONCLUSION: The FMO3 rs1736557 AA genotype was related to an increased the antiplatelet potency of clopidogrel in Chinese CAD patients. Additional studies are required to verify this finding.

AGXT2: An unnegligible aminotransferase in cardiovascular and urinary systems.

Cardiovascular diseases (CVDs) and renal impairment interact in a complex and interdependent manner, which makes clarification of possible pathogenesis between CVDs and renal diseases very challenging and important. There is increasing evidence showing that both asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) play a crucial role in the development of CVDs as well as in the prediction of cardiovascular events. Also, the plasma levels of ADMA and SDMA were reported to be significantly associated with renal function. Alanine-glyoxylate aminotransferase 2 (AGXT2) is reported to be involved in ADMA and SDMA metabolism, thus deficiency in the expression or activity of AGXT2 may play a part in the progression of cardiovascular or renal diseases through affecting ADMA/SDMA levels. Here, we focused our attention on AGXT2 and discussed its potential impact on CVDs and renal diseases. Meanwhile, the review also summarized the functions and recent advances of AGXT2, as well as the clinical association studies of AGXT2 in cardiovascular and urinary systems, which might arouse the interest of researchers in these fields.

CD80 DNA methylation and single-nucleotide polymorphism associated with clopidogrel response: a whole-genome DNA methylation analysis in acute coronary syndrome.

Background: Dual antiplatelet therapy with clopidogrel and aspirin is the primary treatment for patients who undergo percutaneous coronary intervention. However, the interindividual difference in clopidogrel response is remarkable, and high on-treatment platelet reactivity (HTPR) can increase the risk of thrombotic events after percutaneous coronary intervention. Objective: We studied novel accessible factors that possibly affect clopidogrel response in DNA methylation. Methods: Methylation 850K bead chips were used to detect DNA methylation levels. The platelet reactivity index (PRI) was determined in 330 subjects with acute coronary syndrome (ACS) after administration of clopidogrel 300 mg loading dose or at least 5 days of 75 mg daily maintenance dose. Results: Overall, 32 discovery samples showed extreme clopidogrel response: 16 with HTPR (PRI > 75%) and 16 with non-HTPR (PRI < 26%). Overall, 61 differential methylation loci (DMLs) were observed between the 2 groups. Most were in the open sea and intergenic regions in the genome. In the validation stage, HTPR showed a lower level of CD80_cg06300880 methylation. Carriers of rs34394661 AA genotype, a CpG-single-nucleotide polymorphism at the CD80_cg06300880 locus, showed an increased odds for HTPR (overall odds ratio of patients with ACS = 7.31, 95% CI: 1.69-31.59, P = .008; non-ST elevation myocardial infarction-ACS: odds ratio = 12.69, 95% CI: 1.68-96.08, P = .01) and decreased CD80_cg06300880 methylation (P < .0001). Multivariate regression analysis showed that both CYP2C19 poor metabolizers and CD80_rs34394661 AA (P = .009) genotype were associated with higher odds for HTPR in the overall samples. In contrast, CD80_cg06300880 methylation (P = .002) caused lower odds for HTPR in patients with non-ST elevation myocardial infarction-ACS. Conclusion: CD80_cg06300880 and CpG-single-nucleotide polymorphism rs34394661 could be independent predictors of HTPR with clopidogrel therapy.

Influence of GAS5/MicroRNA-223-3p/P2Y12 Axis on Clopidogrel Response in Coronary Artery Disease.

Background Dual antiplatelet therapy based on aspirin and P2Y12 receptor antagonists such as clopidogrel is currently the primary treatment for coronary artery disease (CAD). However, a percentage of patients exhibit clopidogrel resistance, in which genetic factors play vital roles. This study aimed to investigate the roles of GAS5 (growth arrest-specific 5) and its rs55829688 polymorphism in clopidogrel response in patients with CAD. Methods and Results A total of 444 patients with CAD receiving dual antiplatelet therapy from 2017 to 2018 were enrolled to evaluate the effect of GAS5 single nucleotide polymorphism rs55829688 on platelet reactivity index. Platelets from 37 patients of these patients were purified with microbeads to detect GAS5 and microRNA-223-3p (miR-223-3p) expression. Platelet-rich plasma was isolated from another 17 healthy volunteers and 46 newly diagnosed patients with CAD to detect GAS5 and miR-223-3p expression. A dual-luciferase reporter assay was performed to explore the interaction between miR-223-3p and GAS5 or P2Y12 3'-UTR in (human embryonic kidney 293 cell line that expresses a mutant version of the SV40 large T antigen) HEK 293T and (megakaryoblastic cell line derived in 1983 from the bone marrow of a chronic myeloid leukemia patient with megakaryoblastic crisis) MEG-01 cells. Loss-of-function and gain-of-function experiments were performed to reveal the regulation of GAS5 toward P2Y12 via miR-223-3p in MEG-01 cells. We observed that rs55829688 CC homozygotes showed significantly decreased platelet reactivity index than TT homozygotes in CYP2C19 poor metabolizers. Platelet GAS5 expression correlated positively with both platelet reactivity index and P2Y12 mRNA expressions, whereas platelet miR-223-3p expression negatively correlated with platelet reactivity index. Meanwhile, a negative correlation between GAS5 and miR-223-3p expressions was observed in platelets. MiR-223-3p mimic reduced while the miR-223-3p inhibitor increased the expression of GAS5 and P2Y12 in MEG-01 cells. Knockdown of GAS5 by siRNA increased miR-223-3p expression and decreased P2Y12 expression, which could be reversed by the miR-223-3p inhibitor. Meanwhile, overexpression of GAS5 reduced miR-223-3p expression and increased P2Y12 expression, which could be reversed by miR-223-3p mimic. Conclusions GAS5 rs55829688 polymorphism might affect clopidogrel response in patients with CAD with the CYP2C19 poor metabolizer genotypes, and GAS5 regulates P2Y12 expression and clopidogrel response by acting as a competitive endogenous RNA for miR-223-3p.

Aberrant RNA Splicing Events Driven by Mutations of RNA-Binding Proteins as Indicators for Skin Cutaneous Melanoma Prognosis.

The worldwide incidence of skin cutaneous melanoma (SKCM) is increasing at a more rapid rate than other tumors. Aberrant alternative splicing (AS) is found to be common in cancer; however, how this process contributes to cancer prognosis still remains largely unknown. Mutations in RNA-binding proteins (RBPs) may trigger great changes in the splicing process. In this study, we comprehensively analyzed DNA and RNA sequencing data and clinical information of SKCM patients, together with widespread changes in splicing patterns induced by RBP mutations. We screened mRNA expression-related and prognosis-related mutations in RBPs and investigated the potential affections of RBP mutations on splicing patterns. Mutations in 853 RBPs were demonstrated to be correlated with splicing aberrations (p < 0.01). Functional enrichment analysis revealed that these alternative splicing events (ASEs) may participate in tumor progress by regulating the modification process, cell-cycle checkpoint, metabolic pathways, MAPK signaling, PI3K-Akt signaling, and other important pathways in cancer. We also constructed a prediction model based on overall survival-related AS events (OS-ASEs) affected by RBP mutations, which exhibited a good predict efficiency with the area under the curve of 0.989. Our work highlights the importance of RBP mutations in splicing alterations and provides effective biomarkers for prediction of prognosis of SKCM.

Association of N6AMT1 rs2254638 Polymorphism With Clopidogrel Response in Chinese Patients With Coronary Artery Disease.

Dual antiplatelet treatment with aspirin and clopidogrel is the standard therapy for patients undergoing percutaneous coronary intervention (PCI). However, a portion of patients suffer from clopidogrel resistance (CR) and consequently with recurrence of cardiovascular events. Genetic factors such as loss-of-function variants of CYP2C19 contribute a lot to CR. Recently, the N-6-adenine-specific DNA methyltransferase 1 (N6AMT1) rs2254638 polymorphism is reported to be associated with clopidogrel response. To validate the association between N6AMT1 rs2254638 polymorphism and clopidogrel response, 435 Chinese CAD patients receiving aspirin and clopidogrel were recruited. N6AMT1 rs2254638 and CYP2C19 * 2/ * 3 polymorphisms were genotyped. Platelet reaction index (PRI) was measured by VASP-phosphorylation assay after treated with a 300 mg loading dose (LD) clopidogrel or 75 mg daily maintenance dose (MD) clopidogrel for at least 5 days. There was a significant difference in PRI between LD cohort and MD cohort. Carriers of CYP2C19 * 2 allele showed significantly increased PRI in the entire cohort and in respective of the MD and LD cohorts (p < 0.001, p = 0.003, p < 0.001, respectively). However, carriers of CYP2C19 * 3 allele exhibited significantly higher PRI only in the entire cohort and LD cohort (p = 0.023, p = 0.023 respectively). PRI value was significantly higher in CYP2C19 PM genotyped patients as compared with those carrying the IM genotypes and EM genotype (p < 0.001). Besides, carriers of the rs2254638 C allele showed significantly higher PRI in entire cohort and in the LD cohort (p = 0.023, p = 0.008, respectively). When the patients were grouped into clopidogrel resistance (CR) and non-clopidogrel resistance (non-CR) groups, CYP2C19 * 2 was associated with increased risk of CR in the entire cohort, the LD cohort and the MD cohort (p < 0.001, p < 0.001, and p = 0.019, respectively). Carriers of the rs2254638 C allele also showed increased risk of CR in the entire cohort and the LD cohort (p = 0.024, and p = 0.028, respectively). N6AMT1 rs2254638 remained as a strong predictor for CR (TC vs. TT: OR = 1.880, 95% CI = 1.099-3.216,p = 0.021; CC vs. TT: OR = 1.930, 95% CI = 1.056-3.527, p = 0.032; TC + CC vs. TT: OR = 1.846, 95%CI = 1.126-3.026, p = 0.015) after adjustment for confounding factors. Our study confirmed the influence of CYP2C19 *2 and rs2254638 polymorphisms on clopidogrel resistance in Chinese CAD patients. Both CYP2C19 * 2 and N6AMT1 rs2254638 polymorphism may serve as independent biomarkers to predict CR.

CRISPLD1 rs12115090 polymorphisms alters antiplatelet potency of clopidogrel in coronary artery disease patients in Chinese Han.

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is a recommended treatment for coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI) to reduce the rate of ischemic events and stent thrombosis. However, high on-treatment platelet reactivity (HTPR) during clopidogrel therapy for some patients may lead to outcome failure and occurrence of cardiovascular events. Amounts of studies have proved that genetic factors may contribute to HTPR. In our study, we explored the predictive value of 10 single nucleotide polymorphisms (SNPs) in 8 genes indicated by exome sequencing with clopidogrel efficacy. METHODS: Two hundred and forty-one Han Chinese CAD patients (mean age: 61 ±â€¯10 years) receiving dual antiplatelet therapy were recruited, among which 118 patients administered with 300 mg loading dose (LD) clopidogrel for 12-24 h and 123 subjects administered with 75 mg/day maintain dose (MD) clopidogrel for at least 5 days before discharge. The platelet reaction index (PRI) was determined to reflect clopidogrel response in the patients. Venous blood samples were drawn from all participants to extract genomic DNA. MassARRAY, Sanger sequencing and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) were used to determine the genotypes of 10 SNPs. RESULTS: Allelic tests showed significant differences in genotype distribution between HTPR and normal on-treatment platelet reactivity (NTPR) patients for 3 SNPs including CYP2C19 rs4244285 (CYP2C19*2) (co-dominant model: p = 0.003, dominant model: p = 0.004, recessive model: p = 0.012), CRISPLD1 rs12115090 (co-dominant model: p = 0.011, dominant model: p = 0.004), and LTA4H rs11108379 (dominant model: p = 0.041). After adjusting for covariates including clinical characteristics of patients, concomitant medications and complications, we confirmed that carriers of the CYP2C19*2 showed significantly increased risk of HTPR (*2/*2 vs *1/*1: OR = 12.266, 95% CI: 1.336-112.592, p = 0.027; *1/*2 + *2/*2 vs *1/*1: OR = 2.202, 95% CI: 1.083-4.480, p = 0.029). Contrarily, carriers of the CRISPLD1 rs12115090 C allele showed significantly reduced risk of HTPR (CC vs AA: OR = 0.242, 95% CI: 0.078-0.752, p = 0.014; CA + CC vs AA: OR = 0.457, 95% CI: 0.232-0.904, p = 0.024) in Chinese CAD patients. In addition, carriers of the CYP2C19*2 allele showed significantly increased PRI (*1/*2 vs *1/*1: p = 0.008, 2/*2 vs 1/*1: p < 0.001, *2/*2 vs 1/*2: p = 0.011), while patients carrying the rs12115090 C allele showed significantly decreased PRI than the wild-type AA homozygotes (CA vs AA: p = 0.046, CA + CC vs AA: p = 0.023). CONCLUSION: CYP2C19*2 reduced the antiplatelet potency of clopidogrel and increased the risk of HTPR, while CRISPLD1 rs12115090 A>C polymorphism increased the antiplatelet potency of clopidogrel. Genetic tests, especially for CYP2C19*2 are recommended in Han Chinese CAD patients before using of clopidogrel.