CYP4F2 Research Articles

Isolation of the exon‐switching variant, CYP4F2b, from human hepatic carcinoma (HCC) and its role in modulating epithelial‐mesenchymal transition (EMT) through Twist2.

Cytochrome P450 IV (CYP4) are a family of omega‐hydroxylase enzymes. We have previously shown that these fatty acid omega‐hydroxylases function in the hydroxylation of various chain‐length saturated and unsaturated fatty acids in the endoplasmic reticulum. These dicarboxylate products then undergo peroxisomal β‐oxidation, yielding shorter chain fatty acids. In humans, the CYP4F family members hydroxylate long‐chain fatty acid (>C16) and the bioactive eicosanoids, arachidonic acid (HETE) and pro‐inflammatory leukotrienes B4 (LTB4). In the human liver, CYP4F2a metabolizes long‐chain fatty acids and arachidonic acid to the vasoactive 20‐HETE. We have identified a new variant, CYP4F2b from human hepatic carcinoma that is produced from the CYP4F2 gene by exon switching. We have compared the expression of CYP4 members in human HCC and matched healthy human liver. We observed increased expression of CYP4F2b in HCC compared to controls, as well as increased fatty acid omega‐hydroxylation, with associated elevations of acetyl‐CoA/acetate in HCC, and decreased activity and expression of the acetyl‐CoA thioesterase 12 (ACOT12). Increased acetyl‐CoA levels activate the basic helix‐loop‐helix (bHLH) transcription factor Twist2, which initiates an epithelial‐mesenchymal cell transition (EMT). We propose that increased omega‐hydroxylation of fatty acids by CYP4F2b and subsequent peroxisomal β‐oxidation increases cellular acetyl‐CoA levels in HCC, leading to activation of Twist2 and progression of EMT.Support or Funding InformationNEOMED foundation

Prioritizing rs7294 as a mirSNP contributing to warfarin dosing variability.

Aim: The role of mirSNPs in the 3'UTR of VKORC1, CYP2C9 and CYP4F2 genes that could influence warfarin dose variability via a discrete miRNA-mediated mechanism remains unexplained. Methods: Genotypic data in the 1000 Genomes dataset were analyzed for pair-wise linkage disequilibrium and allelic enrichment. Results: MirSNP rs7294 in the 3'UTR of VKORC1 gene displayed varying strengths of linkage disequilibrium with rs9923231 and rs9934438 across populations, albeit consistently associated with higher warfarin dose requirements based on genome-wide association studies, meta-analysis and population-based association studies. In silico analysis predicted altered hybrid stability for the hsa-miR-133a-3p conserved binding site, providing evidence for miRNA-mediated gene regulation. Conclusion: The results support the inclusion of rs7294 as a functional variable for population-specific dosing algorithms to improve dosing accuracy.

Rapid detection of CYP2C9, CYP2C19,CYP4F2,VKORC1 and ABCB1 gene polymorphisms by liquid phase chip technology

Objective To establish a method for simultaneous and rapid detecting of the polymorphisms in Cytochrome P450 2C9 (CYP2C9), CYP2C19, CYP4F2, Vitamin K epoxide reductase (VKORC1) and ATP-binding cassette subfamily B member1 (ABCB1) gene, which were associated with warfarin and clopidogrel, based on liquid phase chip technology. Methods Method establishment. The eight gene sequences near targeted sites related to warfarin and clopidogrel were found in Genbank, and the specific primers and probes were designed. Through multiple PCR amplification, followed by allele specific primer extension (ASPE), and MagPlex-Tag microspheres hybridization, the suspension array Luminex 200 system step-by-step, the genotypes were determined by fluorescence signal. The reaction system was optimized and its methodological evaluation was performed. 260 patients with antithrombotic therapy from Dongguan houjie hospital were recruited in this study form June 2017 to December 2018. The eight genotypes of the 260 patients were detected by the established method, and the results were compared with the sequencing results. Results The results of 260 samples showed that allelic median fluorescence intensity (MFI) ratios of homozygotes (mutant/wild-type) were all greater than 0.9 or less than 0.1, and all the allelic MFI ratios of heterozygotes were between 0.3 and 0.6. The within run and between run coefficients of variance for allelic MFI ratios were lower than 6.4% and 10.9%, respectively. The minimum DNA template requirements was 0.75ng. The genotypes of 260 patients determined by the established method were completely concordant with the sequencing results. Conclusion A method was established successfully for rapid detecting the genotypes which associated with warfarin and clopidogrel based on liquid phase chip technology. Key words: Liquid phase chip technology; Allele-specific primer extension; Warfarin; Clopidogrel; Single nucleotide polymorphism

Genetic variants in CYP4F2 were significantly correlated with susceptibility to ischemic stroke

BackgroundIschemic stroke (IS) is a serious cardiovascular disease and is associated with several single nucleotide polymorphisms (SNPs). However, the role of Cytochrome P450 family 4 subfamily F member 2 (CYP4F2) gene in IS remains unknown. Our study aimed to explore whether CYP4F2 polymorphisms influenced IS risk in the Han Chinese population.MethodsWe selected 477 patients and 495 controls to do a case-control study, and five SNPs in CYP4F2 gene were successfully genotyped. And we evaluated the associations using the Chi-squared test, independent sample t test, and genetic models analyses. Logistic regression analysis was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).ResultsIn this study, rs12459936 and rs3093144 were associated with IS risk in the overall. After stratified analysis by age (> 61 years), rs3093193 and rs3093144 were related to an increased risk of IS, whereas rs12459936 was related to a decreased risk of IS. In addition, we found that three SNPs (rs3093193, rs3093144 and rs12459936) were associated with the susceptibility to IS in males. We also found five SNPs in the CYP4F2 gene had strong linkage.ConclusionsThree SNPs (rs3093193, rs3093144 and rs12459936) in the CYP4F2 were associated with IS risk in a Chinese Han population. And, CYP4F2 gene may be involved in the development of IS.

Population Genomics Analysis Revealed Origin and High-altitude Adaptation of Tibetan Pigs

Tibetan pig is native to the Qinghai-Tibet Plateau and has adapted to the high-altitude environmental condition such as hypoxia. However, its origin and genetic mechanisms underlying high-altitude adaptation still remain controversial and enigmatic. Herein, we analyze 229 genomes of wild and domestic pigs from Eurasia, including 63 Tibetan pigs, and detect 49.6 million high-quality variants. Phylogenomic and structure analyses show that Tibetan pigs have a close relationship with low-land domestic pigs in China, implying a common domestication origin. Positively selected genes in Tibetan pigs involved in high-altitude physiology, such as hypoxia, cardiovascular systems, UV damage, DNA repair. Three of loci with strong signals of selection are associated with EPAS1, CYP4F2, and THSD7A genes, related to hypoxia and circulation. We validated four non-coding mutations nearby EPAS1 and CYP4F2 showing reduced transcriptional activity in Tibetan pigs. A high-frequency missense mutation is found in THSD7A (Lys561Arg) in Tibetan pigs. The selective sweeps in Tibetan pigs was found in association with selection against non-coding variants, indicating an important role of regulatory mutations in Tibetan pig evolution. This study is important in understanding the evolution of Tibetan pigs and advancing our knowledge on animal adaptation to high-altitude environments.

Association Between the CYP4F2 Gene rs1558139 and rs2108622 Polymorphisms and Hypertension: A Meta-Analysis.

Objective: To investigate the association between the CYP4F2 gene rs1558139 and rs2108622 polymorphisms and hypertension. Materials and Methods: In this meta-analysis, we searched databases for case-control studies published before May 2018 examining the associations between two polymorphic sites of the CYP4F2 gene (rs1558139 and rs2108622) and hypertension. The fixed or random effects model chosen was selected according to the heterogeneity of the studies to calculate the pooled odds ratios (OR) and corresponding 95% confidence intervals (95% CI). Results: Six articles in total were analyzed in this study; three investigated the rs1558139 polymorphism and six investigated the rs2108622 polymorphism. The pooled OR and 95% CI using the dominant model for rs1558139, and both the homozygous model and the recessive model of rs2108622 were statistically significant giving values of 0.83 (0.71-0.96), 0.83 (0.71-0.98), and 1.24 (1.07-1.44), respectively. The pooled OR and 95% CI of the rs1558139 polymorphism in the subgroup analysis based on gender were 1.25 (1.08-1.45) and 0.98 (0.85-1.13), whereas the results for the rs2108622 polymorphism were 1.03 (0.86-1.24) and 0.91 (0.72-1.14). Conclusion: Our meta-analysis demonstrates that the rs1558139 and rs2108622 single nucleotide polymorphisms of the CYP4F2 gene are associated with hypertension, with a particularly strong link between the rs1558139 polymorphism in males.

Significance of CYP4F2 polymorphism on oral anticoagulation therapy with acenocoumarol in South Indian patients with mechanical heart valves

BackgroundThe coumarin group of oral anticoagulants has a narrow therapeutic range and wide inter-individual variability. Polymorphism of VKORC1 and CYP2C9 genes are the major genetic determinants of the drug-dose response. Our study aimed to investigate the role of CYP4F2 (1347 G > A) polymorphism on the acenocoumarol daily dose requirement, and its interaction with VKORC1 and CYP2C9 polymorphism. Methods301 Rheumatic Heart Disease (RHD) patients with mechanical cardiac valves were recruited. Genotyping for CYP4F2, VKORC1 and CYP2C9 was done by PCR-RFLP. CYP4F2 genotype distribution GG, GA and AA was 23.5%, 51.5% and 25% respectively. The mean daily dose requirement for variant homozygous patients (AA) was 0.46 folds more when compared to wild type (GG) (Adjusted OR 0.46; 0.21–0.99, p = .048). However, on combined genotype analysis of CYP4F2, VKORC1 and CYP2C9 there was no significant difference in mean dose requirement. ConclusionThe homozygous genotype (AA) of CYP4F2 gene was more prevalent in our study cohort. No significant association was found between CYP4F2 gene polymorphism and acenocoumarol mean dose requirement, both when analyzed individually and in combination with VKORC1 and CYP2C9 polymorphisms.

The prevalence of allelic variants of VKORC1, CYP2C9 and CYP4F2 genes in Zaporizhzhia region population

Objective – to determine the allele frequency of VKORC1, CYP2C9 and CYP4F2 genes in Zaporizhzhia region population. Materials and methods . We investigated 94 individuals at the age of 56 (47; 62) years (men – 23, women – 71) who underwent preventive examination at the “Health” Diagnostic Center based on the ESMC “University Clinic” of the Zaporizhzhya State Medical University. To investigate the polymorphism of CYP2C9, CYP4F2, VKORC1 genes the polymorphic chain reaction method was used. Results. It was established that in Zaporizhzhia region population, the frequency of detection of CYP2C9*2 polymorphic variants is: C/C – 80.9 %, C/T – 19.1 %, T/T – not observed; CYP2C9*3: A/A – 89.0 %, A/C – 11.0 %, C/C – not observed; CYP4F2: C/C – 50.0%, C/T – 40.4 %, T/T – 9.6 %; VKORC: 1 G/G – 40.4 %, G/A – 49.0 %, A/A – 10.6 %. It was discovered that the frequency of registration of polymorphic variants of genes CYP2C9, CYP4F2, VKORC1 varies in different geographic regions, that justifies the expediency of determining these genotypes for each population. Conclusions. The implementation of pharmacogenetic testing based on the polymorphism of genes that affect warfarin metabolism for the warfarine dose titration is perspective.

Prosthetic valve thrombosis - association of genetic polymorphisms of VKORC1, CYP2C9 and CYP4F2 genes.

Prosthetic Valve Thrombosis (PVT), in spite of the advances in the valve design and the material used, remains a serious complication of mechanical cardiac valve replacement. The factors influencing the development of PVT are: thrombogenicity of the valve, hemodynamics of the transprosthetic blood flow and ineffective anticoagulation. Genetic polymorphism of the genes VKORC1 (-1639 G > A and 1173 C > T), CYP2C9 (∗2 & ∗3 alleles) and CYP4F2 (1347 G > A) are known to influence the anticoagulant dose-effect response. Since there has not been any earlier study on the direct influence of gene polymorphism on the development of PVT, we investigated into this association.Genotyping for the genes VKORC1, CYP2C9 and CYP4F2 was carried out by conventional PCR-RFLP method for 91 consecutive PVT patients. Subjects of our earlier study served as controls (n = 136).Female patients and patients with smaller prosthetic valve size were more prone to developing PVT (68%, n = 62). Patients bearing A allele of CYP4F2 1347 G > A polymorphism exhibited a fivefold increased risk of PVT (OR = 5.022 (1.39–18.04), P = .013). G allele of VKORC1 when analyzed in combination of genotypes showed a fourteen fold increased risk for developing PVT (OR = 14.25 (5.52–36.77), P = 0.001). CYP2C9 (∗2&∗3) gene polymorphism did not show any significant association with PVT (OR = 1.54 (0.128 – 18.82), P = .731).Patients bearing A allele of CYP4F2 showed an increased risk of developing PVT in our case – control study.

Profiling cytochrome P450 family 4 gene expression in human hepatocellular carcinoma.

Cytochrome P450 family 4 (CYP4) enzymes are known as microsomal omega (ω)-hydroxylases that metabolize fatty acids, eicosanoids, vitamin D and carcinogens. Thus, CYP4 enzymes may influence tumor development and progression. The aim of the present study was to evaluate the CYP4 expression profile in hepatocellular carcinoma (HCC) and its clinical relevance. The present study obtained CYP4 mRNA expression data for 377 HCC cases from The Cancer Genome Atlas cohort and performed Kaplan-Meier survival, Gene Ontology functional enrichment, and gene set enrichment analysis (GSEA). In addition, the level of CYP4F2 protein expression was evaluated in matched pairs of HCC and non-tumor tissue samples and the results were correlated with the clinicopathological characteristics of HCC (n=113). HCC survival analyses indicated better overall survival in patients with high CYP4F2, CYP4F12 and CYP4V2 mRNA expression levels; the results for histological grade and Tumor-Node-Metastasis stage supported these results. GSEA revealed high levels of CYP4F2, CYP4F12 and CYP4V2 mRNA expression to be negatively correlated with the expression of cell cycle-associated genes. CYP4F2 protein expression was higher in non-neoplastic liver tissue than in HCC tissue and positively correlated with favorable pathological tumor stage (I vs. II–IV; P=0.022) and was a good independent prognostic factor for overall survival (P=0.004). These results demonstrate that the expression levels of the genes CYP4F2, CYP4F12 and CYPV2 are favorable prognostic factors in HCC and suggest the potential predictive diagnostic and prognostic roles of CYP4F2, CYP4F12 and CYPV2 gene expression in HCC.

FREQUENCIES OF POLYMORPHISMS IN THE CYTOCHROME’S P450 GENES OF WARFARIN TRANSFORMATION IN A EUROPEAN POPULATION OF EASTERN SIBERIA

Background. Genotypes of the cytochrome p450 isoform (CYP2C9 and CYP4F2) determine warfarin dose requirements. Frequencies of risk alleles and genotypes of CYP2C9 and CYP4F2 gene vary in different races and ethnic groups.Aim. This study analyzed the frequencies of *2, *3 alleles of CYP2C9 gene and the 1347 C>T allele of CYP4F2 gene in the Caucasians of Eastern Siberia, and compare with other populations.Materials and methods. Participants were 147 patients (Caucasians): 67 (45.58 %) man and 80 (54.42 %) women), taking warfarin for the prevention of thrombosis with a mean age of 64.74 ± 14.29 years. There were patients with atrial fibrillation – 77 (52.38 %) persons, coronary artery disease – 10 (6.80 %), pulmonary embolism – 5 (3.40 %), 15 (10.20 %) patients after implantation of an mechanical heart valve, etc. The subjects were genotyped for CYP2C9 (*1,*2,*3), and CYP4F2 (1347 C>T) by real-time polymerase chain reaction (RT-PCR) using “Pharmacogenetics Warfarin” reagent kits (DNA technology, Russia).Results. 69.4 % of Caucasians of Eastern Siberia (Russians), have two functional alleles (*1/*1) of CYP2C9 (they’re extensive/normal metabolizers), the number of intermediate metabolizers (*1/*2, *1/*3) was 29.8 % and 0.68 % of slow metabolizers (*3/*3). Homozygous carriers of two non-functional alleles *2 and *3 (*2/*2, *2/*3) were absent. Carriers of one coumarin-resistant Т-allele of CYP4F2 were 57 (38.7 %) respondents, two coumarin-resistant alleles – 10 (6.8 %) respondents.Conclusions. Frequencies of polymorphisms in the Cytochrome’s p450 genes of warfarin transformation in a European population of Eastern Siberia have no differences with other European populations of the world

Development and application of a rapid and sensitive genotyping method for pharmacogene variants using the single-stranded tag hybridization chromatographic printed-array strip (STH-PAS)

Genetic polymorphisms contribute to inter-individual variability in the metabolism of multiple clinical drugs, including warfarin, thiopurines, primaquine, and aminoglycosides. A rapid and sensitive clinical assessment of various genome biomarkers is, therefore, required to predict the individual responsiveness of each patient to these drugs. In this study, we developed a novel genotyping method for the detection of nine pharmacogene variants that are important in the prediction of drug efficiency and toxicity. This genotyping method uses competitive allele-specific PCR and a single-stranded tag hybridization chromatographic printed-array strip (STH-PAS) that can unambiguously determine the presence or absence of the gene variant by displaying visible blue lines on the chromatographic printed-array strip. Notably, the results of our STH-PAS method were in 100% agreement with those obtained using standard Sanger sequencing and KASP assay genotyping methods for CYP4F2 gene deletion. Moreover, the results were obtained within 90 min, including the PCR amplification and signal detection processes. The sensitive and rapid nature of this novel method make it ideal for clinical genetic testing to predict drug efficacy and toxicity, and in doing so will aid in the development of individualized medicine and better patient care.

The Influence of CYP4F2 Polymorphisms on Warfarin Doses in Korean Patients with a Variety of Diseases

Purpose We sought to determine if the CYP4F2 gene could affect warfarin maintenance dosage in Korean patients with a variety of diseases. CYP4F2 was reported to affect warfarin dose, but it was controversial. Some papers showed that CYP4F2 genotype could affect warfarin stable dose to some extent. But other papers reported that CYP4F2 genotype did not affect warfarin dose. Methods We enrolled 101 patients treated with warfarin in our registry. Non-genetic factors (clinical characteristics, stable warfarin dose, INR, medication information) and CYP4F2 polymorphisms were assessed. The definition of warfarin stable dose was the amount of medication given to maintain the patient’s INR within the target range throughout at least 3 consecutive laboratory measurements separated by at least 1 week. Each patient’s target therapeutic INR range was determined by the clinicians according to the indication for warfarin treatment. Results In our study, average patient age was 64.0± 11.9 years. Females accounted for 52% of the sample. The average warfarin maintenance dose was 3.26± 1.38 (1-9) mg/day. Compared with CYP4F2 wild type patients (GG), the patients carrying a CYP4F2 heterozygous variant (GA) or a CYP4F2 homozygous variant (AA) required higher warfarin dose. The mean warfarin dose in the patients with the CYP4F2 AA genotype was 4.1± 1.9 mg/day, while that for the patients with the CYP4F2 GA genotype was 3.3± 1.3 mg/day, and that for the patients with the CYP4F2 GG genotype was 3.0± 1.2 mg/day. The difference among them was significant (P= 0.038). Conclusion CYP4F2 polymorphisms statistically influenced the stability of warfarin maintenance dosage in Korean patients with a variety of diseases. Keywords: CYP4F2 polymorphisms, Warfarin dose, Korean

Association Between ABCB1 Polymorphism and Stable Warfarin Dose Requirements in Brazilian Patients.

The ideal dose of the oral anticoagulant warfarin varies widely among patients, mainly due to genetic factors. Genetic variations that impact warfarin pharmacokinetics and the vitamin K cycle are plausible candidates for being associated with warfarin dose requirements. Therefore, the aim of this study was to assess whether polymorphisms in the ABCB1 and CYP4F2 genes were associated with stable warfarin dose requirements in Brazilian patients. This retrospective study included samples from 309 individuals. Genotyping of ABCB1 c.3435C>T and CYP4F2 c.1297G>A were performed by polymerase chain reaction followed by melting curve analysis (HRM-PCR) and TaqMan® genotyping assay, respectively. Stable doses were adjusted in a linear multiple regression model for age, gender, body mass index, self-reported race, use of amiodarone, CYP2C9 (*2 and *3), VKORC1 c.1639G>A, and ABCB1 c.3435C>T or CYP4F2 c.1297G>A. By performing a univariate analysis of variance, we found that the warfarin patients who carry ABCB1 c.3435T variant alleles (CT and TT genotypes) need fewer warfarin stable doses in comparison with the individuals that are CC wild-type: 2.5 (p = 0.003) and 4.3 (p < 0.001) mg/week less, respectively, for the overall group of patients on stable anticoagulation therapeutics (n = 309); and 5.5 (p = 0.006) and 10.2 (p < 0.001) mg/week less, respectively, for the self-declared non-white stable subgroup (n = 76). No statistically significant differences in dose requirements were observed according to CYP4F2 genotypes. In conclusion, our results suggest ABCB1 c.3435C>T variant may influence warfarin dose requirements in Brazilian patients, when associated with other genotypic, demographic and clinical factors.

Impact of VKORC1, CYP4F2 and NQO1 gene variants on warfarin dose requirement in Han Chinese patients with catheter ablation for atrial fibrillation

BackgroundThe anticoagulation of atrial fibrillation catheter ablation during the perioperative stage does matter and should be treated with discretion. We aimed to assess impact of three important genes participating in vitamin K cycle (i.e. VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566) on the daily stable warfarin dose requirement in Sichuan Han Chinese patients with catheter ablation of atrial fibrillation.MethodsA total of 222 atrial fibrillation patients taking stable warfarin therapy after catheter ablation operation were enrolled in this study. The study population included had high (≥2) risk according to the CHA2DS2-VASc risk score. Genotypes of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 were analyzed by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Multiple linear regression analysis was applied to depict the impact of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 on the daily stable warfarin dose requirement.ResultsCarriers of VKORC1 rs9923231 AG/GG genotypes required significantly higher warfarin dose (3.03 ± 0.28 mg/day, 7.19 mg/day, respectively) than AA carriers (2.52 ± 0.07 mg/day; P < 0.001). Carriers of CYP4F2 rs2108622 CT/TT genotypes required significantly higher warfarin dose (3.38 ± 0.22 mg/day, 2.79 ± 0.19 mg/day, respectively) than CC carriers (2.41 ± 0.08 mg/day; P < 0.001). However, the warfarin dose for carriers of NQO1 rs1800566 CT/TT genotypes (2.46 ± 0.24 mg/day, 3.01 ± 0.27 mg/day, respectively) was not significantly higher than that for the CC carriers (2.33 ± 0.1 mg/day). The multiple linear regression model including genotypes and demographic characteristics, could explain 20.1% of individual variations in the daily stable warfarin dose in Sichuan Han Chinese. VKORC1 rs9923231 contributed most (15%) to the individual variations in daily stable warfarin dose, while CYP4F2 rs2108622 contributed least (3%).ConclusionNQO1 rs1800566 is not a significant genetic factor of warfarin dose for Han Chinese, whereas VKORC1 rs9923231 and CYP4F2 rs2108622 are significant genetic factors, which could explain 15% and approximately 3% of individual variations in the daily stable warfarin dose respectively.

Effect of CYP2C9, VKORC1, CYP4F2, and GGCX gene variants and patient characteristics on acenocoumarol maintenance dose: Proposal for a dosing algorithm for Moroccan patients.

We investigated the impact of non-genetics factors, and single nucleotide polymorphisms (SNPs) in VKORC1, CYP2C9, CYP4F2, and GGCX on acenocoumarol dosage in Moroccan adult's patients, in order to develop an algorithm to predict acenocoumarol dose for Moroccan patients. Our study consisted of 217 Moroccan patients taking a maintenance dose of acenocoumarol for various indications. The patients were genotyped for VKORC1 -1639 G>A, VKORC1 1173 C>T, CYP2C9*2, CYP2C9*3, CYP4F2 1347 G>A and GGCX 12970 C>G SNPs. The statistical analysis was performed using the SPSS software. The age and SNPs in VKORC1 and CYP2C9 were significantly associated with the weekly acenocoumarol dose requirement (p = 0.023, p = 0.0001 and p = 0.001 respectively). There was no association found between the weekly acenocoumarol dose and the CYP4F2 or GGCX variants (p-value > 0.05). Non-parametric analysis confirmed the accumulate effect of variant alleles at VKORC1 -1639 G>A, VKORC1 1173 C>T and CYP2C9 SNPs on the acenocoumarol dose requirement. With 90.24% less dose required for one patient carrying homozygote variant at VKORC1 -1173 (TT) and CYP2C9 *x/*x haplotype. The multiple linear regression analysis showed that mutation in VKORC1 -1639, VKORC1 1173 SNPs, or in CYP2C9 haplotype reduces the mean acenocoumarol weekly dose to 25.4%, 23.4% and 6.2%, respectively. The R2 for multiple regression analysis final model was found to be 35.9%. In this work we were able to establish the factors influencing interindividual sensitivity to the anticoagulant therapy that can help physicians to predict optimal dose requirement for long term therapy.

A Novel Polymorphism in the Promoter of the CYP4A11 Gene Is Associated with Susceptibility to Coronary Artery Disease.

Enzymes CYP4A11 and CYP4F2 are involved in biosynthesis of vasoactive 20-hydroxyeicosatetraenoic acid and may contribute to pathogenesis of coronary artery disease (CAD). We investigated whether polymorphisms of the CYP4A11 and CYP4F2 genes are associated with the risk of CAD in Russian population. DNA samples from 1323 unrelated subjects (637 angiographically confirmed CAD patients and 686 age- and sex-matched healthy individuals) were genotyped for polymorphisms rs3890011, rs9332978, and rs9333029 of CYP4A11 and rs3093098 and rs1558139 of CYP4F2 by using the Mass-ARRAY 4 system. SNPs rs3890011 and rs9332978 of CYP4A11 were associated with increased risk of CAD in women: OR = 1.26, 95% CI: 1.02–1.57, P = 0.004, and Q = 0.01 and OR = 1.45, 95% CI: 1.13–1.87, P = 0.004, and Q = 0.01, respectively. Haplotype G-C-A of CYP4A11 was associated with increased risk of CAD (adjusted OR = 1.41, 95% CI: 1.12–1.78, and P = 0.0036). Epistatic interactions were found between rs9332978 of CYP4A11 and rs1558139 of CYP4F2 (P interaction = 0.025). In silico analysis allowed identifying that SNP rs9332978 is located at a binding site for multiple transcription factors; many of them are known to regulate the pathways involved in the pathogenesis of CAD. This is the first study in Europeans that reported association between polymorphism rs9332978 of CYP4A11 and susceptibility to coronary artery disease.

The rs2108622 polymorphism is related to the early risk of ischemic stroke in non-valvular atrial fibrillation subjects under oral anticoagulation.

Oral anticoagulant treatments, such as vitamin K antagonists (VKAs), are the main treatments administered to atrial fibrillation (AF) patients in order to prevent ischemic stroke (IS). However, the genes involved in the VKA metabolism can undergo variations in a single nucleotide (SNP). These SNPs may then affect the VKA target enzyme (VKORC1), VKA degradation enzyme (CYP2C9), and vitamin K bioavailability enzyme (CYP4F2). We genotyped these SNPs in a cohort of patients with non-valvular AF who were under VKA treatment after suffering an IS. Clinical variables, CHADS2-VASC score and data about the international normalized ratio (INR) within the therapeutic range were all recorded. DNA was extracted from blood and genotyping was carried out by DNA sequencing. The main endpoint was the time from VKA onset to IS. Of a total of 356 consecutive IS patients monitored, 33 were included in the study. The median time to the event was 2248.0 days (interquartile range [IQR] 896.3-3545.3). The median CHADS2-VASC score was 4.0 (IQR 3.0-6.0). When we considered the risk of IS within 2 years under VKA treatment, we found that only the rs2108622 AA genotype was significantly associated with this endpoint (early IS) (hazard ratio 6.81, 95% CI 1.37-33.92, p = 0.019). Kaplan-Meier curve analysis also showed a significant relationship between early IS and rs2108622 AA genotype (Log rank p = 0.022). The CYP4F2 gene rs2108622 polymorphism was associated with a risk of early IS in NV-AF patients under VKA treatment.

Correlation between Rs2108622 Locus of CYP4F2 Gene Single Nucleotide Polymorphism and Warfarin Dosage in Iranian Cardiovascular Patients.

Background: Many cardiovascular diseases may require lifelong anticoagulation therapy. Warfarin is the most prescribed medication in this regard, however, it has serious side effects. Recently the new issue regarding to warfarin dosing is considered in which some single nucleotide polymorphisms (SNPs) affecting cytochrome P450 system can impact on warfarin metabolism and dosing. Methods: 230 cardiovascular patients have participated in the study. The INR levels was 1.5 - 3.5 with a mean range of 2.8. The subjects were divided into two case and control groups. The rs2108622 SNP of the CYP4F2 gene and its effect on warfarin dosing in these patients was accessed. Results: The results of our study showed a correlation between age and warfarin dosage. The overall frequency of the CC and TT allele of rs2108622 was 53.1% and 18.6%. Daily average dose of warfarin in CC, CT and TT variants was 3.5 ± 1.6, 4.5 ± 2.1 and 5.3 ± 2.1 respectively. The daily warfarin dose in patients with CC allele was significantly lower than that for CT or TT. The patients with TT allele required a 1.8 mg/day higher dose of warfarin than that of CC. Conclusion: While there are many studies regarding to relation of age and warfarin dose, however, there are different results about pharmacogentic status and warfarin dose in different ethnics. Our study demonstrates that polymorphism in the CYP4F2 rs2108622 has a significant impact on the warfarin requirements in Iranian patients. However the cost benefit of such test should be considered, too.

The Association of the rs2108622 Single Nucleotide Polymorphism in the CYP4F2 Gene with Resistance to Clopidogrel

The Association of the rs2108622 Single Nucleotide Polymorphism in the CYP4F2 Gene with Resistance to Clopidogrel