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(1) Background: Prescribing apixaban for stroke prevention has significantly increased in patients with non-valvular atrial fibrillation (NVAF). The ABCB 1 genotype can influence apixaban absorption and bioavailability. The aim of the present study was to assess the factors that influence apixaban's plasma level and to establish if a certain relationship has clinical relevance. (2) Methods: Fifty-three NVAF patients were treated with 5 mg apixaban twice/day (70.0 years, range: 65-77, 60.4% men). Trough and peak plasma concentrations of apixaban were determined by liquid chromatography-tandem mass-spectrometry (LC-MS/MS), and ABCB 1 genotyping was performed. (3) Results: Apixaban plasma concentrations varied considerably. They were higher in women than in men (311.2 ng/dL vs. 252.2 ng/dL; p = 0.05) and were lower in patients with heart failure (149.4 ng/dL vs. 304.5 ng/dL; p < 0.01). Creatinine clearance was inversely correlated with the apixaban plasma level (Spearman correlation: r = -0.365; p = 0.007 for trough concentrations). No statistically significant differences between the genotypic groups of ABCB 1 rs1045642 and ABCB 1 rs4148738 were found in the trough or peak apixaban plasma concentrations. (4) Conclusions: Pharmacokinetic parameters are influenced by several clinical factors of which renal function is the major determinant. Plasma concentrations measured in women had higher values than those measured in men, and heart failure was associated with decreased plasma levels of apixaban.

Background and Aims: The mutations in the gene that encodes vitamin K epoxide reductase (VKOR) enzyme are responsible for low levels of vitamin K. The purpose of this study was to evaluate whether the presence of the VKORC1 -1639 G> A polymorphism is a risk factor for non-variceal upper gastrointestinal bleeding (UGIB) in patients without concomitant therapy with vitamin K antagonists., Methods: This case-control study comprised 163 consecutive patients diagnosed with UGIB and 178 controls, in whom the diagnosis of UGIB was excluded. The following data were recorded: age, gender, alcohol consumption, smoking, history of UGIB, nonsteroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin consumption. Genetic analysis included genotyping for the VKORC1 -1639 G>A polymorphism., Results: History of UGIB (OR 3.463, CI95% 1.463-8.198, p=0.005), smoking (OR 2.498, CI95% 1.358-4.597, p=0.003), alcohol consumption (OR 3.283, CI95% 1.796-6.000, p<0.001), use of NSAIDs (OR 4.542, CI95% 2.502-8.247, p<0.001) or of low-dose aspirin (OR 2.390, CI95% 1.326-4.310), and the VKORC1 -1639 G> A AA genotype (OR 1.364, CI95% 0.998-1.863, p=0.05) were associated with an increased risk of UGIB. The risk of UGIB was analyzed in patients with genotype AA who used aspirin or NSAIDs. The genotype AA has not kept its status of independent risk factor (p=0.3). In subjects with NSAIDs/aspirin therapy and genotype AA there was a two times higher chance of UGIB compared to those under NSAIDs/aspirin therapy alone (OR 7.6 vs. 3.6, p<0.001)., Conclusion: Patients with non-variceal UGIB caused by the use of NSAIDs or low-dose aspirin are more frequent carriers of the VKORC1 -1639 G>A AA genotype, as compared to those without UGIB.

XPC, XPD, XPF, and XPG genes are implicated in the nucleotide excision repair (NER) system. Gene polymorphisms in NER repair system may influence the individual's capacity to recognize and repair DNA lesions, thus increasing the cancer risk. We hypothesized that these gene polymorphisms might influence the probability of developing acute myeloid leukemia (AML). We investigated the XPC, XPD, XPF, and XPG gene polymorphisms in 108 AML cases and 163 healthy controls. Also cytogenetic analyses besides FLT3 and DNMT3A mutations status were investigated. We found that variant genotypes (heterozygous and homozygous) of XPD 2251A > C and 22541A > C and the heterozygous genotype of XPG 3507G > C were associated with the risk of developing AML (OR = 2.55; 95% CI = 1.53-4.25; p value <0.001; OR = 1.66, 95 % CI = 1.02-2.72; p value = 0.047, and OR = 2.36; 95 % CI = 1.32-4.21; p value = 0.004, respectively). No association was found between white blood cell counts, FLT3, DNMT3A mutations, cytogenetic risk group, and variant genotypes of none of the analyzed polymorphisms. Variant homozygous XPF 673C > T genotype was associated with higher dose of cytosine arabinoside treatment administrated to AML patients (p value = 0.04). No differences were found regarding survival time and variant genotype in the investigated gene polymorphisms with the exception of XPD 2251A > C. In conclusion, XPD 22541A > C, XPD 2251A > C, and XPG 3507G > C gene polymorphisms confer susceptibility to AML, while XPC 2920A > C, XPF-673C > T, XPF 11985A > G are not associated with AML.

Oxidative stress might contribute to the occurrence of cancers, including the hematological ones. Various genetic polymorphisms were shown to increase the quantity of reactive oxygen species, a phenomenon that is able to induce mutations and thus promote cancers. The purpose of the study was to evaluate the association between CAT C262T, GPX1 Pro198Leu, MnSOD Ala16Val, GSTM1, GSTT1, and GSTP1 Ile105Val gene polymorphisms and acute myeloid leukemia risk, in a case-control study comprising 102 patients and 303 controls. No association was observed between AML and variant genotypes of CAT, MnSOD, GSTM1, and GSTT1 polymorphisms. Our data revealed a statistically significant difference regarding the frequencies of GPX1 Pro198Leu and GSTP1 Ile105Val variant genotypes between AML patients and controls (p < 0.001). Our results showed no association in the distribution of any of the CAT C262T, GPX1 Pro198Leu, GSTM1, GSTT1, and GSTP1 polymorphisms regarding age, gender, FAB subtype, cytogenetic risk groups, FLT3 and DNMT3 gene mutations, and overall survival. Our data suggests that the presence of variant allele and genotype of GPX1 Pro198Leu and GSTP1 Ile105Val gene polymorphisms may modulate the risk of developing AML.

In the base excision repair pathway, the predominant DNA damage repair mechanism, X-ray repair cross-complementing group 1 (XRCC1) gene, has a crucial role. Defects in repair pathways are involved in cancer pathogenesis. Therefore, DNA repair genes might be involved in acute myeloid leukemia (AML) susceptibility. Our study aimed to evaluate the relationship between XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphisms and AML. Sixty-nine patients with AML and 147 healthy controls were included. We noted a significant association between the polymorphisms Arg194Trp (p-value = 0.0002 for Trp allele) and Arg399Gln (p-value = 0.003 for Gln allele) and AML risk. There was a significantly better overall survival among patients with AML with wild-type homozygous compared to those with at least one variant allele in the case of Arg194Trp (p-value = 0.0019) and Arg399Gln polymorphisms (p-value = 0.049). Our study suggests the involvement of XRCC1 Arg194Trp and Arg399Gln polymorphisms in the genetic predisposition to AML. These two XRCC1 polymorphisms could also be prognostic markers in AML as they were significantly associated with overall survival.

Aim: To investigate the genotype-phenotype correlation in Romanian patients treated with acenocoumarol., Material and Methods: We studied 301 consecutive patients who required treatment with acenocoumarol, admitted within the Municipal Hospital of Cluj-Napoca and the Heart Institute "Niculae Stănciou" in Cluj-Napoca over a 3-year period. For each patient we recorded clinical parameters which could interfere with the achievement of stable therapeutic international normalized ratio (INR). We performed genetic analysis which consisted of genotyping the CYP2C9 gene and the VKORC1 gene. Patients were divided in three groups according to the acenocoumarol dose needed to reach a stable INR: the low dose group (≤7mg/week), the medium dose group (>7mg and <28mg/week) and the high acenocoumarol dose group (>28mg/week)., Results: We found that patients' age was significantly different between groups (p<0.001). No differences existed between groups regarding the pathologies which required anticoagulation therapy or the concomitant treatment. The following parameters increased the odds of receiving a low dose of acenocoumarol: patient's age over 65years (OR, 3.2; p=0.01; 95%CI: 1.24-8.25), the presence of the CYP2C9*3 allele (OR, 3.4; p=0.006; 95%CI: 1.41-8.34), and the GA or AA genotype of c.-1639G>A polymorphism of VKORC1 (OR, 6.5; p=0.01; 95%CI: 1.38-30.5; respectively OR, 11.6; p=0.003; 95%CI: 2.26-59.58). A high acenocoumarol dose was less likely to be administered to an elderly patient (OR, 0.24; p=0.001; 95%CI: 0.1-0.56) or to a patient with the GA or AA genotype (OR, 0.2; p<0.001; 95CI%: 0.09-0.45; respectively OR, 0.05; p=0.006; 95%CI: 0.007-0.43)., Conclusion: The stable therapeutic dose of acenocoumarol is dependent of patient's age, the presence of the CYP2C9*3 allele and the c.-1639G>A polymorphism of VKORC1., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. According to the Rome III criteria, IBS is defined as recurrent abdominal pain or discomfort for at least 3 d per month during the previous 3 mo associated with two or more of the following symptoms: improvement with defecation, onset associated with a change in the frequency of stool and/or onset associated with a change in form or appearance of stool. There is growing evidence regarding the genetic contribution in IBS, however the precise etiology of IBS is still unknown. The evaluation of the genetic influence is based on twin studies, familial aggregation and genetic epidemiological investigations. Most studies showed a concordance for IBS significantly greater in monozygotic than in dizygotic twins. The majority of the studies have shown that familial aggregation may represent exposures to a similar environment, as well as the influence of genetic factors. Whereas no specific gene has been identified in association with IBS, recent studies have noticed the importance of polymorphisms in the promoter region of the serotonin reuptake transporter gene, G-protein beta 3 subunit gene (C825T), cholecystokinin receptor (CCKAR gene 779T>C), and high-producer tumor necrosis factor genotype. Further studies are necessary to determine how genetic factors influence the clinical manifestations and therapeutical response in IBS patients.