G894T polymorphism of eNOS gene is a predictor of response to combination of inhaled corticosteroids with long-lasting β(2)-agonists in asthmatic children

Aim: Nitric oxide synthase enzymes have an important role in airway inflammation in asthmatic children. In the present study, the association between eNOS gene polymorphisms and response to inhaled corticosteroids (ICS) and long-lasting β(2)-agonists (LABAs) was investigated. Patients & methods: A total of 81 asthmatic children treated with ICS plus LABAs and 96 healthy controls were genotyped for eNOS G894T and -786T/C polymorphisms and their haplotypes using the PCR-RFLP method. Results: G894T and -786T/C polymorphisms were not associated with asthma susceptibility. Among asthmatic children, 894TT carriers had higher change in forced expiratory volume in 1 s (FEV(1)) in response to ICS plus LABAs compared with 894GG carriers (21.9 ± 3.8 vs 1.6 ± 1.9%; p < 0.001). In responders (FEV(1) change ≥7.5%), frequency of 894TT genotype was significantly higher than in nonresponders (26.2 vs 2.6%, p < 0.001). Results for the -786T/C polymorphism alone were less clear and in most cases nonsignificant. Conclusion: The G894T polymorphism was associated with response to ICS and may serve as a useful pharmacogenetic marker of response to ICS plus LABAs in asthmatic children. Original submitted 10 May 2012; Revision submitted 13 July 2012.     

eNOS T-786C polymorphism affects atorvastatin-induced changes in erythrocyte membrane fluidity

Purpose  Statins have pleiotropic effects, including endothelial nitric oxide synthase (eNOS) upregulation and increased nitric oxide formation, which can be modulated by a genetic polymorphism in the promoter region of the eNOS gene (T-786C). Here, we report our investigation of whether this polymorphism modulates the effects of atorvastatin on the fluidity of erythrocyte membranes. Methods  We genotyped 200 healthy subjects (males, 18–60 years of age) and then randomly selected 15 of these with the TT genotype and 15 with the CC genotype to receive placebo or atorvastatin (10 mg/day oral administration) for 14 days. Cell membrane fluidity was evaluated by electron paramagnetic resonance (EPR) and spin-labeling method. The EPR spectra were registered on a VARIAN-E4 spectrometer. Thiobarbituric acid-reactive species (TBA-RS) and plasma membrane cholesterol were determined in the erythrocytes. Results  Atorvastatin reduced membrane fluidity in CC subjects (P < 0.05) but not in those with the TT genotype (P > 0.05). While no significant differences were found in plasma membrane cholesterol concentrations, higher TBA-RS concentrations were found in the CC subjects than in the TT subjects (P < 0.05). Conclusions  These findings suggest that a short treatment with atorvastatin is disadvantageous to subjects with the CC genotype for the T-786C polymorphism compared to those with TT genotype, at least in terms of the hemorheological properties of erythrocytes.     

Polymorphisms of genes controlling homocysteine levels and IQ score following the treatment for childhood ALL

INTRODUCTION: One of the causes of long-term morbidity associated with the treatment of acute lymphoblastic leukemia (ALL) is late neurotoxicity manifesting as impairment of higher cognitive functions. Cranial radiation therapy (CRT) and chemotherapeutic agents, particularly methotrexate (MTX), are often suggested to be major contributing factors for its development. Homocysteinemia that arises as a result of MTX-induced folate depletion was proposed to play a role in MTX-related neurotoxicity. Several enzymes are essential to maintain the homocysteine levels. Their different functional forms, associated with common genetic polymorphisms, may modulate homocysteine levels and thereby influence MTX-associated neurotoxicity. OBJECTIVES: To test this hypothesis we assessed whether the variants of the methylene tetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), cystathionine beta-synthase (CBS) and endothelial nitric acid synthase (eNOS, NOS3) genes, acting either independently or in conjunction with other risk factors, influenced the cognitive functioning in ALL patients. The influence of the genes was measured by estimating the change in IQ scores over a period of 4 years post ALL diagnosis. RESULTS: Two variants, the CBS 844ins68 polymorphism and NOS3 894T homozygosity, were associated with a change in IQ scores (p = 0.01 and 0.007, respectively). A multivariate model obtained through step-wise selection pointed to the importance of the NOS3 894TT genotype only. This effect appears to be dependent on CRT; IQ decline was apparent among individuals with the 894TT genotype who received radiation therapy (p = 0.03). Furthermore, additional factors affecting IQ were identified, including the treatment administered (i.e., CRT; p = 0.02) and a younger age at diagnosis (p = 0.003), and the modifying effect of the treatment protocols was also noted (p = 0.04). CONCLUSION: The results suggest that NOS3 genotyping might identify individuals that are susceptible to intellectual impairment following ALL treatment.     

内皮型一氧化氮合酶基因多态性与原发性高血压的关系研究

目的:探讨天津市汉族人群内皮型一氧化氮合酶(eNOS)基因G894T和27 bp数目可变的串联重复序列(VNTR)多态性与原发性高血压的关系.方法:对500例研究对象根据血压分为原发性高血压组350例和对照组150例,采用PCR-RFLP对2组eNOS第7外显子G894T及第4内含子VNTR进行基因多态性分型.分析不同基因型与高血压发病的关系.结果:(1)2组eNOS G894T位点2组基因型和基因频率差异无统计学意义(P＞0.05).(2)高血压组eNOS第4内含子VNTR aa+ab基因型及a等位基因频率高于对照组(P＜0.05).(3) eNOS基因G894T和第4内含子VNTR对高血压的发生无协同作用.结论:eNOS基因G894T多态性与原发性高血压无关,而第4内含子VNTR多态性与原发性高血压存在相关性,两者无协同作用.     

内皮型一氧化氮合酶基因G894T多态性与ACEI降压疗效相关性研究

目的探讨原发性高血压患者内皮型一氧化氮合酶基因(eNOS)G894T多态性与血管紧张素转换酶抑制剂(ACEI)降压疗效之间的关系。方法 281例1-2级原发性高血压患者经安慰剂治疗2周后,血压符合入选标准者分别给予咪达普利5～10mg/d或贝那普利10～20mg/d,治疗6周。用酚-氯仿法提取基因组DNA,采用PCR结合限制性内切酶片段长度多态性(RFLP)方法检测eNOS基因型,分析不同基因型组与ACEI降压疗效的关系。结果本研究中eNOS 3种基因型频率分别为GG66.2％、GT27.8％、TT6.0％,等位基因G、T的频率分别为0.80和0.20。ACEI治疗后,eNOS基因GG、GT、TT组收缩压下降值分别为(14.51±11.19)mmHg,(16.11±12.31)mmHg,(12.38±14.30)mmHg;舒张压下降值分别为(8.95±6.56)mmHg,(9.00±6.92)mmHg,(9.37±4.80)mmHg,3组间收缩压与舒张压下降值均无统计学差异。结论 eNOS基因G894T多态性与ACEI降压疗效无关。     

Determination of the effects of eNOS gene polymorphisms (T-786C and Glu298Asp) on nitric oxide levels in a methylmercury-exposed population

Nitric oxide (NO) is a potent vasodilator with multiple protective effects involved in the regulation of cardiovascular functions. Endothelial NO synthase (eNOS) gene polymorphisms and environmental factors, such as mercury (Hg) exposure, may influence NO levels and increase the risk of cardiovascular damage. The aim of this study was to determine the role of the T-786C and Glu298Asp polymorphisms of the eNOS gene on nitrite concentrations following Hg exposure in humans. It was postulated that Hg exposure might decrease circulating nitrite concentrations and that variants in the eNOS gene might enhance the adverse effects of Hg resulting in increased risk of cardiovascular disease. Blood samples were collected from 202 volunteers exposed to methylmercury (MeHg) following fish consumption. Blood Hg concentrations (BHg) were determined by inductively coupled plasma-mass spectrometry and nitrite plasma concentration by a chemiluminescent method. The mean Hg concentration was 50.5 ± 35.4 μg/L and mean nitrite concentration was 251.4 ± 106.3 nM. There were no significant differences in age, arterial blood pressure, body mass index, heart rate, and concentrations of Hg and nitrite concentrations between the genotype groups . When data were grouped together (TC + CC and TT group), there were still no marked differences. A multiple regression model indicated that decreased NO production was predominantly due to Hg, age, and gender. Polymorphisms did not seem to influence this effect. Our findings suggest that eNOS gene polymorphisms (T-786C and Glu298Asp) are not associated with an increased risk for cardiovascular diseases in MeHg-exposed subjects.     

Effects of endothelial nitric oxide synthase gene polymorphisms on platelet function,nitric oxide release,and interactions with estradiol

Impaired platelet-derived nitric oxide (NO) contributes to acute coronary syndromes by enhancing platelet recruitment and thrombus formation. Polymorphic variants of the endothelial NO synthase (eNOS) gene have been associated with cardiovascular diseases. To examine whether eNOS variants affect platelet-derived NO and platelet function, and to assess the effects of estradiol on platelet function, we studied platelets from 47 healthy caucasians who were genotyped for eNOS polymorphisms in the promoter region (T-786 C), in intron 4, and in exon 7 (Glu298Asp). Platelet aggregation, platelet-derived NO and superoxide production were measured in control samples and samples pretreated with 17-alpha-estradiol (10 nmol/l). The occurrence of variants in the promoter region (P = 0.002) or in exon 7 (P = 0.007), but not in intron 4 (P > 0.05), were associated with lower levels of platelet-derived NO. An increased (P = 0.047) release of superoxide was observed with platelets from subjects with the variant in the promoter region, but not with other eNOS genetic variants. The eNOS gene polymorphisms did not affect ADP-induced platelet aggregation (P > 0.05). However, estradiol significantly increased platelet aggregation (P = 0.004), and platelet-derived superoxide (P = 0.047) in individuals homozygous for the variant in exon 7, but not in subject with other genotypes. These data demonstrate that the eNOS variants in the promoter region and in exon 7 decrease platelet-derived NO and that estradiol significantly increases platelet aggregation in homozygous for the variant in exon 7 but not in subjects with other genotypes, suggesting that eNOS variants may influence the thrombotic response.     

Association of Angiotensinogen (M235T) Gene Polymorphism with Blood Pressure Lowering Response to Angiotensin Converting Enzyme Inhibitor (Enalapril)

Purpose: It has been suggested that genetic backgrounds, which have an association with essential hypertension, may also determine the responsiveness to ACE inhibitor. We determined the association of angiotensinogen (M235T) gene polymorphism with essential hypertension and the relationship between polymorphism in the angiotensinogen (M235T) gene and blood pressure response to ACE inhibitor (Enalapril) in patients with essential hypertension from northern Indian subjects. Methods: 250 patients with essential hypertension and 250 normal healthy controls from Delhi and surrounding areas were recruited for the investigation. Blood pressure was recorded before and after 6 weeks of treatment with ACE inhibitors, Enalapril. Genotyping were carried out by polymerase chain reaction and Restriction fragment length polymorphism technique. Results: Statistically significant association of T allele was observed with essential hypertension [x2 = 14.67, p = 0.00013, Odds ratio = 1.76 (1.3-2.32) at 95% CI], the relative risk at 95% CI being 1.28 (1.2-1.54). The decrease in systolic blood pressure and diastolic blood pressure after six weeks of treatment of the patients carrying TT genotype (SBP = 26±17.4 mmHg, DBP = 14.83±7.6mmHg) were greater than the groups carrying MT (SBP = 3.0±7.8 mmHg, DBP =6.2±3.0 mmHg) and MM genotypes (SBP = 1.2±0.8 mmHg, DBP = 0.10±12.1 mm Hg. Conclusions: The angiotensinogen (M235T) gene polymorphism is significantly associated with essential hypertension. Patients carrying TT genotype had higher blood pressure lowering response when treated with ACE inhibitor, Enalapril than those carrying MM and MT genotypes suggesting that the T allele may be a possible genetic marker for essential hypertension. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.     

A Pharmacogenetics‐based Approach to Reduce Cardiovascular Mortality with the Prophylactic Use of Statins

Abstract: Nitric oxide (NO) is the main endothelial‐derived relaxation factor and plays a major role in cardiovascular homeostasis. This key signalling molecule is synthesised by a family of nitric oxide synthases (NOS), and the endothelial isoform (eNOS) is the most important for nitric oxide formation in the cardiovascular system. Cardiovascular drugs including statins increase eNOS expression and up‐regulate NO formation, and this effect may be responsible for protective, pleiotropic effects produced by statins. However, the genetic background may also affect NO formation in the cardiovascular system, and recent studies have shown that genetic polymorphisms in the eNOS gene modify endogenous NO formation and the risk of developing cardiovascular diseases. For example, cases with the CC genotype for the T^?786C polymorphism in the eNOS gene are at increased cardiovascular risk when compared with those with the TT genotype. Interestingly, pharmacogenetic studies have recently indicated that atorvastatin improves NO formation more clearly in these individuals. However, it is not known whether this polymorphism really increases cardiovascular morbidity and mortality, and whether atorvastatin or other statins attenuate the morbidity and mortality rates in cases with the CC genotype. If proved true, then statins‐induced up‐regulation of eNOS and increased NO formation could compensate for a genetic ‘disadvantage’ in cases with the CC genotype. This could be a significant advance in the prevention of cardiovascular events. It is necessary although to validate this hypothesis with clinical trials which will require a long follow‐up to assess relevant clinical events and not only surrogate biomarkers.     

Association of serotonin 5-HT2A receptor binding and the T102C polymorphism in depressed and healthy Caucasian subjects.

Serotonin 5-HT2A receptor (5-HT2A) binding is reported to be altered in individuals with suicidal behavior, mood disorders, and aggressive-impulsive traits. Genetic association with major depression, suicidal behavior, and aggressive-impulsive traits has not been established. This study examines the possible association of the 5-HT2A gene C102T polymorphism with the receptor binding kinetics, and clinical overt phenotypes. The study population included 63 healthy volunteers and 152 subjects with mood disorders, 56 of whom had a history of suicide attempts. All were Caucasian. Platelet 5-HT2A binding kinetics (Bmax and KD) were assayed and adjusted for seasonal variation. All subjects were genotyped for the T102C polymorphism. Clinical phenotype was determined by structured clinical interview. The TT genotype was associated with higher Bmax in all subjects (F=3.53, df=2,211; p=0.03), controlling for diagnosis. Bonferroni-adjusted post hoc testing showed higher binding in the TT compared with TC genotype in the control group (F=7.56, df=2,60, p=0.001), but not in the mood-disordered subjects. No difference was found in genotype and allele distribution between the mood-disordered subjects, with and without suicide attempt history, and controls. Bmax was not related to a diagnosis of mood disorders. The TT genotype appears associated with higher platelet 5-HT2A Bmax in the healthy population, but this genotypic effect appears absent in mood disorders and unrelated to psychopathology.     

Effects of angiotensin receptor blockers on endothelial nitric oxide release: the role of eNOS variants

AIM

Angiotensin II receptor blockers (ARBs) improve endothelial cell (EC)-dependent vasodilation in patients with hypertension through suppression of angiotensin II type 1 receptors but may have additional and differential effects on endothelial nitric oxide (NO) synthase (eNOS) function. To investigate this question, we tested the effects of various ARBs on NO release in ECs from multiple donors, including those with eNOS genetic variants linked to higher cardiovascular risk.

METHODS

The effects of ARBs (losartan, olmesartan, telmisartan, valsartan), at 1 µm, on NO release were measured with nanosensors in human umbilical vein ECs obtained from 18 donors. NO release was stimulated with calcium ionophore (1 µm) and its maximal concentration was correlated with eNOS variants. The eNOS variants were determined by a single nucleotide polymorphism in the promoter region (T-786C) and in the exon 7 (G894T), linked to changes in NO metabolism.

RESULTS

All of the ARBs caused an increase in NO release as compared with untreated samples (P < 0.01, n = 4–5 in all eNOS variants). However, maximal NO production was differentially influenced by eNOS genotype. Olmesartan increased maximal NO release by 30%, which was significantly greater (P < 0.01, n = 4–5 in all eNOS variants) than increases observed with other ARBs.

CONCLUSIONS

The ARBs differentially enhanced NO release in ECs in a manner influenced by eNOS single nucleotide polymorphisms. These findings provide new insights into the effects of ARBs on EC-dependent vasodilation and eNOS function.     

eNOs基因T786C多态性与原发性高血压的关系

目的:探讨内皮型一氧化氮合酶(eNOs)基因T786C多态性与原发性高血压的关系。方法:选取原发性高血压患者266例(高血压组)和健康人群100例(对照组),入院后空腹12h抽取肘正中静脉血4mL,常规测定生化及凝血功能等各项指标。进行eNOs基因T786C的PCR扩增、酶切和基因型分析。分析不同基因型与高血压发病的关系。结果:高血压组的年龄、收缩压、舒张压、体质量指数及有饮酒史者均高于对照组,差异均有统计学意义(P<0.05或P<0.01);其他指标比较差异无统计学意义(P>0.05)。2组TT、TC及CC基因型分布和T、C等位基因频率分布差异均无统计学意义(P>0.05)。高血压组患者中C等位基因携带者的收缩压及舒张压与TT基因型者差异无统计学意义(P>0.05)。影响高血压的因素有年龄、性别和体质量指数。结论:eNOs基因T786C多态性在高血压发病中不起直接作用,可能通过影响相关危险因素参与高血压发病。     

MTHFR基因多态性与下肢DVT的相关性研究

目的探讨N5,N10-亚甲基四氢叶酸还原酶(Methylenetetrahydrofolatereductase,MTHFR)基因多态性与我国东北地区人群下肢深静脉血栓形成(Deepvenousthrombosis,DVT)的关系。方法采用PCR-RFLP检测73例DVT患者和109名健康对照者MTHFRC677T、A1298C突变,计算患者组与对照组的基因型频率、等位基因频率以及突变与DVT的相关性。结果患者组677TT、677CT基因型频率和T等位基因频率分别为38.4%、49.3%和63%,明显高于对照组(分别为15.6%、46.8%和39%。χ2=19.393,P<0.01;χ2=20.200,P<0.01)。677TT和677CT基因型的个体比677CC基因型的个体发生DVT的相对危险分别约高7或3倍(ORTT=7.503,95%可信区间为2.931～19.207;ORTC=3.215,95%CI为1.391～7.434)。患者组与对照组MTHFR1298各基因型和等位基因分布无显著性差异(χ2=3.533,P>0.05;χ2=0.100,P>0.05),但1298CC677CC基因型的个体比1298AA、677CC基因型的个体发生DVT的相对危险约高16倍(OR=16.500,95%CI为1.353～201.290)。结论MTHFR基因C677T和A1298C突变可能为我国东北地区人群下肢DVT的危险因素。     

Renin-angiotensin-aldosterone system gene polymorphisms and antihypertensive response to irbesartan in Chinese hypertensives

The aim of this study was to determine whether specific single nucleotide polymorphisms (SNPs) and their reconstructed haplotypes in renin-angiotensin-aldosterone system (RAAS) genes were associated with antihypertensive reduction to irbesartan treatment. Thousand one forty-two hypertensives were recruited and received 150 mg irbesartan daily for 4 weeks. Blood pressures (BPs) and blood samples, at postdose on the 28th day, were measured. Predose BPs and plasma irbesartan concentrations were also measured. Involved SNPs in RAAS pathway genes were genotyped. Genotype (-344 TC) in the CYP11B2 had a significantly greater systolic blood pressure (SBP) reduction versus the TT genotype (p = 0.001). Subjects with the 174MM genotype of the angiotensinogen (AGT) gene had a significantly greater average SBP reduction (p = 0.025). The C-344T and T1016C polymorphisms in the CYP11B2 gene were both significantly associated with diastolic blood pressure (DBP) reduction (p = 0.026 or p = 0.003). Overall, the three loci-constructed haplotypes of the CYP11B2 gene were associated with DBP reduction (p = 0.008). Haplo-GLM analyses demonstrated that subjects with haplotype CTA had a significantly greater SBP and DBP reductions (p < 0.001 or p = 0.020), whereas subjects with haplotype TAA had a significantly lower SBP and DBP reductions (p < 0.001). Our findings suggested that SNPs and their reconstructed haplotypes in RAAS genes might be involved in the regulation of BP-lowering response to irbesartan in Chinese hypertensives.     

内皮型一氧化氮合酶基因多态性与老年高血压关系的研究

目的:探讨内皮型一氧化氮合酶(eNOS)基因894G/T多态性与老年人原发性高血压病(EH)之间的关系。方法:应用聚合酶链反应限制性片段长度多态性技术对湖北地区汉族129例高血压病患者(EH组)和117例健康者(NT组)的eNOS外显子894位点进行基因分型,生化技术测定其血脂水平。结果:EH组T等位基因频率以及GT+TT基因型分布频率均显著高于NT组(P<0.05);在年龄不同组中这种显著相关性仅存在年龄小于61岁的中青年患者中。结论:eNOS基因可能与老年人群原发性高血压发生无关。     

Pharmacogenetic interactions of three candidate gene polymorphisms with ACE-inhibitors or beta-blockers and the risk of atherosclerosis

AIMS: To investigate whether the angiotensin-converting enzyme (ACE) insertion/deletion (I/D), angiotensinogen M235T or angiotensin II receptor type 1 573C/T polymorphism modify the risk of atherosclerosis associated with beta-blocker or ACE-inhibitor therapy. METHODS: Data were used from the Rotterdam Study, a population-based prospective cohort study in the Netherlands, which started in 1990 and included 7983 subjects of >or= 55 years. In this study, 2216 subjects with hypertension were included. Three subclinical measurements were used for atherosclerosis, i.e. peripheral arterial disease, carotid atherosclerosis and aortic atherosclerosis. The interaction between antihypertensive drugs and genetic polymorphisms on the risk of atherosclerosis was determined with binary logistic regression analysis. RESULTS: The risk of aortic atherosclerosis associated with long-term (>or=4 years) beta-blocker treatment compared with no use of beta-blockers was higher in subjects with the TT genotype than in subjects with the MM genotype of the AGT gene [synergy index (SI) = 3.36; 95% confidence interval (CI) 1.14, 9.97]. The risk of carotid atherosclerosis associated with long-term ACE-inhibitor treatment compared with no use of ACE-inhibitors was lower in subjects with the TT genotype than in subjects with the MM genotype of the AGT gene (SI = 0.20; 95% CI 0.04, 0.95). CONCLUSION: Overall, the risk of atherosclerosis in hypertensives taking a beta-blocker or ACE-inhibitor-based regimen was not strongly modified by any of the three candidate gene polymorphisms.     

Role of the eNOS Glu298Asp variant on the GNB3825T allele dependent determination of alpha-adrenergic coronary constriction

The 825T allele of a polymorphism at GNB3, encoding the G protein beta(3) subunit, is associated with an enhanced coronary blood flow (CBF) reduction in response to alpha(2)-, but not to alpha(1)-adrenoceptor activation. Because the regulation of vascular tone by alpha(2)-adrenoceptors includes direct vasoconstriction as well as vasodilatation by endothelial release of nitric oxide, the eNOS Glu298Asp variant might further contribute to explain the variability of CBF reduction in response to alpha-adrenoceptor activation. Genotyping at the GNB3 and the eNOS gene was performed on 48 individuals receiving either the alpha(1)-adrenoceptor agonist methoxamine (5 mg i.c.) and/or the alpha(2)-adrenoceptor agonist BHT 933 (5 mg i.c.). CBF was calculated from quantitative coronary angiography and intracoronary Doppler flow velocity measurement. To analyse the impact of genotypes and coronary artery disease, a linear regression model was used, including cholesterol levels, heart rate, smoking and mean aortic blood pressure. An initial, univariate analysis suggested an impact of the eNOS Glu298Asp variant on alpha(2)-adrenoceptor-induced coronary constriction (CBF reduction 53.4 ch006.1 TT/TG versus 30.7 ch006.9% GG; P = 0.003). However, multifactorial analysis showed that the GNB3825T allele was associated exclusively with the CBF reduction on alpha(2)-adrenoceptor activation (58.2 +/- 4.4% TT/TC versus 27.9 +/- 4.3% CC; P < 0.0001). Contrary to the initial analysis, the Glu298Asp variant of the eNOS gene provides no additional information on the genetic basis of alpha(2)-adrenoceptor-induced coronary vasoconstriction, which appears exclusively associated to the 825T allele at GNB3. Analysis of modifying genes appears crucial for the understanding of genetic associations.     

Influence of ABCC2, SLCO1B1, and ABCG2 polymorphisms on the pharmacokinetics of olmesartan

This study was designed to determine whether genetic polymorphisms of multidrug-resistant protein 2 (ABCC2), organic anion transporting polypeptide 1B1 (SLCO1B1), and breast cancer resistance protein (ABCG2) have an effect on olmesartan pharmacokinetics in Korean subjects. Sixty-eight healthy male volunteers who participated in previous pharmacokinetics studies of olmesartan medoxomil (single dose, 20 mg or 40 mg) were enrolled. All subjects were analyzed and grouped according to the genotypes of ABCC2, SLCO1B1, and ABCG2. The dose-normalized peak plasma concentration (C(max)) and area under the plasma concentration-time curve (AUCt) values were analyzed. The dose-normalized mean C(max) and AUC(t) in the ABCC2 -24CT genotype group were higher than those in the -24CC genotype group [C(max,dn): CT 26.1 ± 6.5 (ng/mL)/mg versus CC 22.1 ± 6.7 (ng/mL)/mg, P = 0.010, AUC(t,dn): CT 178.7 ± 45.6 (hr·ng(-1)·mL(-1))/mg versus CC 149.9 ± 39.8 (hr·ng(-1)·mL(-1))/mg, P = 0.010]. The difference in AUC(t,dn) between the ABCC2 -1549GG and -1549GA genotype groups was statistically significant [GG 149.0 ± 41.0 (hr·ng(-1)·mL(-1))/mg versus GA 174.1 ± 43.3 (hr·ng(-1)·mL(-1))/mg, P = 0.019]. No significant differences were observed for any other single nucleotide polymorphism in ABCC2, SLCO1B1, or ABCG2. The ABCC2 -24CC genotype group exhibited lower systemic exposure of olmesartan than the -24CT genotype group, whereas no significant differences were observed in the other transporter genotype groups.     

Association of nitric oxide synthase 3 (NOS3) 894 G>T polymorphism with prognostic outcomes of anthracycline in Chinese patients with acute myeloid leukaemia

The aim of the present study was to investigate the influence of the nitric oxide synthase 3 (NOS3) 894 G>T polymorphism on prognostic outcomes of anthracycline in Chinese patients with de novo intermediate‐risk acute myeloid leukaemia (AML) and to examine the gene expression level in relation to genetic variation. In all, 225 Chinese patients with intermediate‐risk AML (at the complete remission stage) treated with anthracycline were enrolled in the study. The 894 G>T polymorphism of the NOS3 gene was analysed by allele‐specific matrix‐assisted laser desorption ionization time‐of‐flight. Expression of NOS3 mRNA was tested in 72 patients of known genotype for NOS3 894 G>T. The clinical characteristics of these patients were obtained from medical records. Survival analysis showed that patients with AML (GG genotype) had a longer overall survival (OS; P = 0.006). After adjusting for age, gender, leucocyte count, haemoglobin level, platelet level, French, American and Britain (FAB) classification, lactate dehydrogenase levels, Eastern Cooperative Oncology Group Performance Status, nucleophosmin gene and fms‐related tyrosine kinase 3 gene, multivariate survival analysis showed that the NOS3 894 G>T polymorphism appeared to be a predicting factor for OS (P = 0.014; hazard ratio = 1.856). However, no significant associations between the NOS3 894 G>T polymorphism and relapse‐free survival and relapse in patients with AML were observed. Gene expression levels were significantly higher in patients with the GG genotype than in patients with the GT and TT genotypes (P = 0.033). The findings suggest that the NOS3 894 G>T variant may be a biomarker for the prediction of OS in Chinese patients with AML.