Pharmacogenetic aspects of efficacy and safety of methotrexate treatment in pediatric acute lymphoblastic leukemia.

OBJECTIVES: To evaluate the role of ABCB1 (C3435T rs1045642, rs1128503, rs2032582, rs4148738), SLCO1B1 T521C rs4149056 genetic polymorphisms in the development of major types of methotrexate (MTX) toxicities and the occurrence of a terminal event (death, relapse) in pediatric АLL. METHODS: The study included 124 patients diagnosed with pediatric ALL. All patients treated according to the protocols of the German BFM group (2002/2009) with high-dose (1,000, 2,000 and 5,000 mg/m2) methotrexate. MTX-related toxicities, including hematologic, hepatic and renal, were evaluated according to the common terminology criteria for adverse events version 5.0 (CTCAE v.5.0). Real-time PCR method was used to investigate polymorphisms of ABCB1 and SLCO1B1 genes. The study material was peripheral blood. RESULTS: A competitive analysis demonstrated significant relationships between MTX ADRs. The results of the study support the existence of relationships between some ADRs and MTX kinetics. An associative analysis showed association with the development of AEs to methotrexate indicating their clinical significance from different genetic polymorphisms protein-transporters. The available results confirm the associations of the studied genes with the increased risk of high doses MTX toxic ADRs and terminal events. CONCLUSIONS: Complementing the existing criteria for pediatric ALL risk groups with pharmacogenetic indicators will allow further individualization of therapy.

Predictive modeling of adverse drug reactions to tamoxifen therapy for breast cancer on base of pharmacogenomic testing.

OBJECTIVES: The present study investigated the analysis of adverse drug reactions (ADRs) to tamoxifen (TAM) in breast cancer patients in relation to the carriage of genetic polymorphisms of genes encoding enzymes of CYP system and transporters of P-glycoprotein (Pg) and predictive models based on it. METHODS: A total of 120 women with breast cancer taking adjuvant TAM were examined for the gene polymorphisms such as CYP2D6*4, CYP3A5*3, CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP2C19*3 and ABCB1 (C3435T). Allelic variants were determined using the real-time polymerase chain reaction method. The research material was double sampling of buccal epithelium. Medical history data and extracts from case histories were used as sources of medical information, on the basis of which questionnaires specially created by us were filled out. RESULTS: An associative analysis showed association with the development of ADRs to TAM indicating their clinical significance from different genetic polymorphisms of CYP2D6, CYP3A5, CYP2C9 and ABCB1. The complex associative analysis performed using mathematical modeling made it possible to build predictive risk models for the development of ADRs such as hot flashes, dyspepsia, bone pain, and asthenia. CONCLUSIONS: Models that include both genetic and non-genetic determinants of ADRs of TAM may further improve the prediction of individual response to TAM.

Association of CYP2C19 Polymorphic Markers with Cardiovascular Disease Risk Factors in Gas Industry Workers Undergoing Periodic Medical Examinations.

INTRODUCTION: Human cytochrome P450 (CYP) enzymes have a wide range of endogenous substrates and play a crucial role in cardiovascular physiology as well as in metabolic processes, so the issue of cytochrome P450 genes investigation has received considerable critical attention in the prevention of cardiovascular diseases (CVDs). AIM: Comprehensive assessment of relationship between CYP2C19*2, CYP2C19*3 polymorphisms and CVD risk factors in gas industry workers undergoing periodic medical examination (PME). MATERIALS AND METHODS: The study included 193 gas industry workers aged 30-55 years without acute diseases as well as exacerbations of chronic diseases, diabetes mellitus, and CVD history. CYP2C19 (rs4244285 and rs4986893) genotyping and analysis of the relationship between CYP2C19*2 and CYP2C19*3 and CVD risk factors were performed. RESULTS: The CYP2C19*2 (A) and CYP2C19*3 (A) loss-of-function alleles frequencies were 20% and 2%, respectively. The frequency of high-normal blood pressure (BP) (130-139 and/or 85-89 mm Hg) detection was higher in the CYP2C19*2 (A) subgroup compared with wild-type GG allele carriers (26.7% vs. 5.2%, p = 0.03) in individuals without arterial hypertension (AH) and BP ≥ 140 and/or 90 mm Hg on PME. The median systolic BP levels were 5 mm Hg higher in CYP2C19*2 (A) group than in CYP2C19*2 (GG) group (125 vs. 120 mm Hg, p = 0.01). There was a similar trend for diastolic BP (85 vs. 80 mmHg, p = 0.08). CYP2C19*2 (A) was associated with higher mean levels of both systolic and diastolic BP (p = 0.015 and p = 0.044, respectively) in patients with AH. CYP2C19*2 was not associated with the other CVD risk factors analyzed. CONCLUSION: The association of CYP2C19*2 with BP level suggests a possible role of this factor in AH development, which requires further research.

CYP2C9 gene polymorphisms influence on antihypertensive effectiveness and hypouricemic effect of losartan among patients with arterial hypertension: an observational study.

OBJECTIVES: CYP2C9 gene polymorphic variants can decrease the effects of losartan, reducing active metabolite (E-3174) formation. Study aims to determine the influence of *2 (+430C>T; rs799853) and *3 (+1075A>C; rs1057910) CYP2C9 gene polymorphic variants on the hypotensive and uricosuric effect of losartan on patients with arterial hypertension. METHODS: Eighty one patients with stage 1-2 arterial hypertension newly diagnosed with ABMP were enrolled in the study. Physicians started losartan treatment and then we measured urine concentration of E-3174/losartan to estimate CYP2C9 activity. After 3-month losartan treatment we compared effectiveness of the therapy with ABPM and plasma uric acid level between carriers of CYP2C9 *1/*1 and CYP2C9 gene polymorphic variants (*2 and *3). RESULTS: Carriage of CYP2C9*2 and CYP2C9*3 alleles reduced the hypotensive effect of losartan (p<0.001, OR=8.13 (95% CI, 2.75-23.97)). Analysis of the ABPM data revealed that blood pressure was significantly higher in patients with polymorphic genotypes. There was no significant difference in uric acid level in plasma and losartan and its metabolite concentration in urine between genotypes. CONCLUSIONS: Carriage of low function polymorphic variants of the CYP2C9 gene (*2 and *3) reduced the hypotensive effect of losartan according to ABPM and don't affect uric acid level in plasma and E-3174/losartan in urine.

Effect of CYP2D6*4, CYP2D6*10 polymorphisms on the safety of treatment with timolol maleate in patients with glaucoma.

OBJECTIVES: Timolol maleate is used for the treatment of glaucoma and metabolized by cytochrome CYP2D6 in the liver. The aim of this study was the evaluation of the influence of CYP2D6*4 and CYP2D6*10 gene polymorphisms on the safety of medications containing 0.5% of timolol maleate as glaucoma treatment in patients with primary open-angle glaucoma (POAG). METHODS: 105 patients with POAG were prescribed glaucoma medications, containing 0.5% timolol maleate. The safety of glaucoma treatment was determined by electrocardiography (ECG) (to assess heart rate (HR) and PQ interval) and blood pressure (BP) measurements. The real-time polymerase chain reaction method was used for the detection of single nucleotide polymorphisms (SNP). RESULTS: The risk of adverse drug reactions was higher in patients with the CYP2D6*4 GA genotype compared with GG: mean HR change at 1 month (2.88 ± 4.68 and 6.44 ± 5.57, p<0.001) and 6 months (5.14 ± 8.93 and 7.88 ± 5.65, p<0.001), mean PQ interval change at 1 (0.01 ± 0.031 and 0.02 ± 0.022, p=0.003) and 6 months (0.01 ± 0.032 and 0.02 ± 0.024, p=0.003). The risk of adverse drug reactions was higher in patients with the CYP2D6*10 CT genotype compared with CC: mean HR change at 1 month (2.94 ± 4.65 and 6.34 ± 5.66, p<0.001) and 6 months (5.20 ± 8.90 and 7.78 ± 5.75, p<0.001), mean PQ interval change at 1 (0.01 ± 0.032 and 0.02 ± 0.021, p=0.014) and 6 months (0.01 ± 0.033 and 0.02 ± 0.022, p=0.014). CONCLUSIONS: CYP2D6*4 and CYP2D6*10 gene polymorphisms may affect a higher risk of timolol-induced bradycardia and increased PQ interval of treatment medications containing 0.5% of timolol maleate in patients with POAG.

Influence of ABCB1, CYP3A5 and CYP3A4 gene polymorphisms on prothrombin time and the residual equilibrium concentration of rivaroxaban in patients with non-valvular atrial fibrillation in real clinical practice.

OBJECTIVE: The study of ABCB1 and CYP3A4/3A5 gene polymorphism genes is promising in terms of their influence on prothrombin time variability, the residual equilibrium concentration of direct oral anticoagulants (DOACs) in patients with atrial fibrillation and the development of new personalized approaches to anticoagulation therapy in these patients. The aim of the study is to evaluate the effect of ABCB1 (rs1045642) C>T; ABCB1 (rs4148738) C>T and CYP3A5 (rs776746) A>G, CYP3A4*22(rs35599367) C>T gene polymorphisms on prothrombin time level and residual equilibrium concentration of rivaroxaban in patients with atrial fibrillation. METHODS: In total 86 patients (42 men and 44 female), aged 67.24 ± 1.01 years with atrial fibrillation were enrolled in the study. HPLC mass spectrometry analysis was used to determine rivaroxaban residual equilibrium concentration. Prothrombin time data were obtained from patient records. RESULTS: The residual equilibrium concentration of rivaroxaban in patients with ABCB1 rs4148738 CT genotype is significantly higher than in patients with ABCB1 rs4148738 CC (P = 0.039). The analysis of the combination of genotypes did not find a statistically significant role of combinations of alleles of several polymorphic markers in increasing the risk of hemorrhagic complications when taking rivaroxaban. CONCLUSION: Patients with ABCB1 rs4148738 CT genotype have a statistically significantly higher residual equilibrium concentration of rivaroxaban in blood than patients with ABCB1 rs4148738 CC genotype, which should be considered when assessing the risk of hemorrhagic complications and risk of drug-drug interactions. Further studies of the effect of rivaroxaban pharmacogenetics on the safety profile and efficacy of therapy are needed.

The Influence of ABCB1 (rs1045642 and rs4148738) Gene Polymorphisms on Rivaroxaban Pharmacokinetics in Patients Aged 80 Years and Older with Nonvalvular Atrial Fibrillation.

INTRODUCTION: ABCB1 gene polymorphisms are associated with rivaroxaban distribution changes and adverse reactions but the data are controversial. AIM: To evaluate the influence of ABCB1 (rs1045642 and rs4148738) gene polymorphisms on rivaroxaban pharmacokinetics in patients aged 80 years and older with nonvalvular atrial fibrillation (NAF). METHODS: 128 patients aged 80 years and older (median [Me] age 87.5 [83.0-90.0] years) with NAF were included. We performed ABCB1 (rs1045642 and rs4148738) genotyping, measured the trough steady-state plasma concentration (Cmin,ss) of rivaroxaban and prothrombin time (PT) and analyzed prior medical records for clinically relevant non-major bleeding (CRNMB). RESULTS: CC genotype carriers had no differences in Cmin,ss (p > 0.05) compared with the CT and TT rs1045642 and rs4148738 genotypes carriers. CC genotype carriers had no differences in PT (p > 0.05) compared with the CT rs1045642 and rs4148738 and TT rs4148738 genotypes carriers. In the TT genotype PT levels were higher than in the CC rs1045642 genotype: Me 14.2 [13.0-16.1] sec vs 13.3 [12.4-14.5] sec (p = 0.049). Incidence of CRNMB was higher in patients with the TT genotype compared with the CC rs1045642 (29.3% vs 4.5%, p = 0.021) and rs4148738 (39.3% vs 8.1%, p = 0.008) and the CT genotype rs4148738 (39.3% vs 14.3%, p = 0.002). CONCLUSION: ABCB1 (rs1045642 and rs4148738) polymorphisms didn't influence rivaroxaban pharmacokinetics in patients aged 80 years and older with NAF. TT carriers developed CRNMB more frequently compared with the CC rs1045642 and the CC and CT rs4148738 genotypes. The haplotype TT-TT haplotype was associated with a higher frequency of CRNMB.

Effect of CYP2C9, PTGS-1 and PTGS-2 gene polymorphisms on the efficiency and safety of postoperative analgesia with ketoprofen.

OBJECTIVES: Patients undergoing cardiac surgery develop post-sternotomy pain syndrome. The aim of this study was evaluation of the influence of CYP2C9, PTGS-1 and PTGS-2 genes polymorphisms on the efficacy and safety of postoperative analgesia with ketoprofen in patients with coronary artery disease after cardiac surgery. METHODS: The study included 90 patients undergoing cardiac surgery. A real-time polymerase chain reaction was used for the detection of single nucleotide polymorphisms (SNP). Pain intensity was measured by the Numeric Rating Scale (NRS). Dyspeptic symptoms were evaluated using the Gastrointestinal Symptom Rating Scale (GSRS). Acute kidney injury (AKI) was determined by Kidney Disease Improving Global Outcomes criteria. RESULTS: Pain intensity by the NRS score was significantly higher in patients with CYP2C9*3 АA genotype compared to АC genotype: 7 [1,10] and 6 [2,7] (p=0.003); 7 [1,10] and 6 [2,7] (p=0.04); 6 [0; 10] and 5 [2,6] (p=0.04); 5 [0; 8] and 3 [0; 8] (p=0.02), on days 1, 2, 3 and 5 in the postoperative period, respectively. GSRS score was higher in patients with CYP2C9*2 CT genotype compared to CС genotype: 19 [15; 42] and 18 [15,36] (p=0.04), respectively. There were no significant differences in the pain intensity, dyspepsia severity and AKI frequency in patients with homozygous and heterozygous genotypes for PTGS-1 rs10306135, PTGS-1 rs12353214, PTGS-2 rs20417. CONCLUSIONS: CYP2C9*3 and CYP2C9*2 gene polymorphisms may affect efficacy and safety of postoperative analgesia with ketoprofen in patients with coronary artery disease after cardiac surgery.

The effect of CYP2D6 and CYP2C9 gene polymorphisms on the efficacy and safety of the combination of tramadol and ketorolac used for postoperative pain management in patients after video laparoscopic cholecystectomy.

OBJECTIVES: One of the key components of ERAS is adequate pain control in the postoperative period. There are no rational schemes for postoperative pain relief. At the same time, adequate postoperative pain relief promotes early activation and early rehabilitation of patients and shortens the duration of the postoperative stay, and does not cause postoperative complications associated with analgesia (weakness, intestinal paresis, nausea and vomiting). The aims of the present study are to assess the possible association of CYP2D6 and CYP2C9 polymorphisms with the efficacy and safety of tramadol and ketorolac in postoperative pain. METHODS: A total of 107 patients were genotyped for CYP2D6 and CYP2C9 polymorphisms. All patients underwent laparoscopic cholecystectomy. Postoperative pain relief was carried out with ketorolac and tramadol. Postoperative pain syndrome was assessed using a visual analogue scale and McGill pain questionnaire. The profile of side effects was assessed by the dynamics of red blood counts as a possible trigger for the development of gastrointestinal bleeding according to the method of global assessment of triggers. RESULTS: Pain was statistically significantly lower in CYP2C9*2 carriers, according to visual analogue scale (VAS): after 12 h - by 1.5 (p=0.002); after 24 h - by 1.1 (p=0.012); after 36 h - by 1.05 (p=0.004); after 48 h - by 0.7 (p=0.026). In CYP2C9*3 carriers the results were not statistically significant. In carriers of CYP2D6*4 pain syndromes were higher at all-time intervals, but statistically reliable results were obtained only after 2 h - by 1.01 (p=0.054) and after 24 h - by 0.8 (p=0.035). The profile of adverse reactions for NSAIDs was evaluated by the dynamics of hemoglobin and erythrocyte indices. A more pronounced decrease in the relative difference in hemoglobin levels was noted in CYP2C9*2 and CYP2C9*3 polymorphism carriers - by 1.7 (p=0.00268) and-by 2.2 (p=0.000143), respectively. CONCLUSIONS: CYP2D6 and CYP2C9 can predict analgesic effectiveness of tramadol and ketorolac. CYP2C9 can predict the risk of gastrointestinal bleeding, including those hidden to ketorolac.

The effect of CYP2D6 and CYP2C9 gene polymorphisms on the efficacy and safety of the combination of tramadol and ketorolac used for postoperative pain management in patients after video laparoscopic cholecystectomy.

OBJECTIVES: One of the key components of ERAS is adequate pain control in the postoperative period. There are no rational schemes for postoperative pain relief. At the same time, adequate postoperative pain relief promotes early activation and early rehabilitation of patients and shortens the duration of the postoperative stay, and does not cause postoperative complications associated with analgesia (weakness, intestinal paresis, nausea and vomiting). The aims of the present study are to assess the possible association of CYP2D6 and CYP2C9 polymorphisms with the efficacy and safety of tramadol and ketorolac in postoperative pain. METHODS: A total of 107 patients were genotyped for CYP2D6 and CYP2C9 polymorphisms. All patients underwent laparoscopic cholecystectomy. Postoperative pain relief was carried out with ketorolac and tramadol. Postoperative pain syndrome was assessed using a visual analogue scale and McGill pain questionnaire. The profile of side effects was assessed by the dynamics of red blood counts as a possible trigger for the development of gastrointestinal bleeding according to the method of global assessment of triggers. RESULTS: Pain was statistically significantly lower in CYP2C9*2 carriers, according to visual analogue scale (VAS): after 12 h - by 1.5 (p=0.002); after 24 h - by 1.1 (p=0.012); after 36 h - by 1.05 (p=0.004); after 48 h - by 0.7 (p=0.026). In CYP2C9*3 carriers the results were not statistically significant. In carriers of CYP2D6*4 pain syndromes were higher at all-time intervals, but statistically reliable results were obtained only after 2 h - by 1.01 (p=0.054) and after 24 h - by 0.8 (p=0.035). The profile of adverse reactions for NSAIDs was evaluated by the dynamics of hemoglobin and erythrocyte indices. A more pronounced decrease in the relative difference in hemoglobin levels was noted in CYP2C9*2 and CYP2C9*3 polymorphism carriers - by 1.7 (p=0.00268) and-by 2.2 (p=0.000143), respectively. CONCLUSIONS: CYP2D6 and CYP2C9 can predict analgesic effectiveness of tramadol and ketorolac. CYP2C9 can predict the risk of gastrointestinal bleeding, including those hidden to ketorolac.

Clinically relevant pharmacogenetic markers in Tatars and Balkars.

This study was aimed to investigate the prevalence of CYP2C9*2 (p.430C > T, rs1799853), CYP2C9*3 (p.1075A > C, rs1057910), CYP4F2*3 (p.1297G > A, rs2108622), CYP2C19*2 (p.681G > A, rs4244285), CYP2C19*3 (p.636G > A, rs4986893), CYP2C19*17 (p.1260C > A, rs12248560), ABCB1 (p.3435C > T, rs1045642), CYP2D6*4 (p.1846G > A, rs3892097), SLCO1B1*5 (p.521T > C, rs4149056) and CES1 (p.1168-33A > C, rs2244613) among Tatars and Balkars ethnic groups living in Russia to provide a basis for future clinical studies concerning on understanding of population-level differences in drug response. The study involved 341 apparently healthy, unrelated, and chronic medication-free volunteers of both sexes of ethnic groups of Tatars and Balkars living in Volga and Caucasus regions of Russia. Genotyping was performed using real-time polymerase chain reaction-based methods. The allelic prevalence of studied markers in ethnic groups were compared with Russians as a largest ethnic group in Russia. Statistically significant differences for the following gene polymorphisms were found between both ethnic groups in respect of different markers and with Russians. Our study shows differences in prevalence of the main relevant pharmacogenetic markers in Tatars and Balkars. These findings should be taken into consideration for personalization algorithms development and pharmacogenetics implementation in regions with ethnic minorities as Russia has.

Antihypertensive Effect Of Amlodipine In Co-Administration With Omeprazole In Patients With Hypertension And Acid-Related Disorders: Cytochrome P450-Associated Aspects.

BACKGROUND: CYP2C19 and CYP3A are the main enzymes involved in omeprazole metabolism, while CYP3A is the principal enzyme family for amlodipine biotransformation. Concomitant use of these drugs in patients with hypertension and acid-related disorders (ARD) might lead to drug-drug interaction. PURPOSE: The aim of the study was to find if adding omeprazole for treating ARD to amlodipine long-term therapy of hypertension influenced blood pressure of CYP2C19 polymorphism carriers. PATIENTS AND METHODS: Fifty-one patients diagnosed with hypertension and ARD were enrolled in the study. Evaluation of antihypertensive therapy was performed by office (OBPM) and ambulatory (ABPM) blood pressure monitoring. Peripheral venous blood was collected for DNA extraction and real-time polymerase chain reaction was performed for CYP2C19*2G681A (rs4244285), CYP2C19*3G636A (rs4986893) and CYP2C19*17C-806T (rs12248560) polymorphisms analysis. RESULTS: Of 51 patients there were 21 extensive metabolizers (EMs), 18 ultrarapid metabolizers (UMs) and 12 intermediate metabolizers (IMs). The results of OBPM showed that antihypertensive effect was significantly more pronounced in IMs compared to EMs or UMs and the average group value in the following parameters: average office systolic blood pressure (BP), dynamics of the average office systolic BP. According to dynamics of diastolic BP, the antihypertensive effect was also significantly higher in IMs than in UMs and the average group value. The results of ABPM revealed that there was a significantly more pronounced antihypertensive effect in IMs compared to all other analyzed groups according to the dynamics of both daytime systolic and 24 hr diastolic BP. The average daytime diastolic BP and its dynamics, the average 24 hr systolic BP and its dynamics were higher in IMs compared to EMs and UMs. CONCLUSION: Adding omeprazole to long-term amlodipine therapy in patients with hypertension and ARD may lead to a significantly more pronounced antihypertensive effect in patients genotyped CYP2C19 IMs.

Genetic determinants of dabigatran safety (CES1 gene rs2244613 polymorphism) in the Russian population: multi-ethnic analysis.

This study was aimed to investigate the prevalence of the CES1 gene (c.1168-33A > C, rs2244613) polymorphism among 12 different ethnic groups living in Russia to provide a basis for future clinical studies concerning genetic determinants of dabigatran safety. The study involved 1630 apparently healthy, unrelated, and chronic medication-free volunteers of both genders from 12 different ethnic groups in Russia: 136 Russians, 90 Avars, 50 Dargins, 46 Laks, 120 Kabardians, 112 Balkars, 244 Ossetians, 206 Mari, 204 Mordvinians, 238 Chuvashes, 114 Buryats and 70 Nanays. Genotyping was performed by using real-time polymerase chain reaction-based methods. The allelic prevalence of the ethnic groups was compared with Caucasus population participating in the RE-LY study. Statistically significant differences for the following gene polymorphism were found between all ethnic groups and RE-LY participants. Based on obtained results, it can be assumed that patients of all ethnic groups living in Russia taking dabigatran have a lower risk of bleeding.

CYP3A and CYP2C19 activity in urine in relation to CYP3A4, CYP3A5, and CYP2C19 polymorphisms in Russian peptic ulcer patients taking omeprazole.

BACKGROUND: Proton pump inhibitors (PPIs) are metabolized by cytochrome P450. CYP2C19 is the main isoenzyme for the majority of PPI, whereas CYP3A family is a secondary enzyme for PPI biotransformation. PURPOSE: The aim of the study was to find if CYP3A4*22, CYP3A5*3, CYP2C19*2, CYP2C19*3, and CYP2C19*17 genotypes are connected with CYP3A and CYP2C19 activities in Russian peptic ulcer patients taking omeprazole. PATIENTS AND METHODS: Forty-eight gastric or duodenal ulcer patients (15 men, 33 women; mean age 55.0±15.3 years, age range 18-91 years) from Moscow region of Russia were enrolled. Peripheral venous blood was collected for DNA extraction, and real-time polymerase chain reaction was performed for CYP3A5*3 A6986G (rs776746), CYP3A4*22 C>T in intron 6 (rs35599367), CYP2C19*2G681A (rs4244285), CYP2C19*3G636A (rs4986893), and CYP2C19*17C-806T (rs12248560) polymorphism analyses. Urine samples of patients were collected in the morning between 6 and 9 am before food or drug intake. Urine cortisol and 6ß-hydroxycortisol concentrations (for CYP3A activity) and omeprazole and 5-hydroxyomeprazole concentrations (for CYP2C19 activity) were measured using high-performance liquid chromatography/mass spectroscopy. RESULTS: We found a connection between CYP2C19 genotypes and CYP3A activity. Median metabolic ratios 6ß-hydroxycortisol/cortisol (25%-75% percentiles) were 2.84 (1.99-4.39) for CYP2C19 extensive metabolizers (EMs), 2.51 (1.86-4.73) for CYP2C19 ultra-rapid metabolizers (UMs), and 1.45 (1.12-2.16) for CYP2C19 intermediate metabolizers (IMs) + poor metabolizers (PMs). A statistically significant difference in CYP3A activity (Mann-Whitney test) was found between CYP2C19 EMs vs CYP2C19 IMs+PMs (p=0.006), between CYP2C19 UMs vs CYP2C19 IMs+PMs (p=0.018), and in multiple comparison Kruskal-Wallis test (p=0.014). CONCLUSION: In CYP2C19 IMs+PMs, CYP3A activity was significantly lower than in CYP2C19 EMs and UMs.

Do CYP2C19 and ABCB1 gene polymorphisms and low CYP3A4 isoenzyme activity have an impact on stent implantation complications in acute coronary syndrome patients?

AIM: The aim of this study was to determine the impact of CYP2C19 and ABCB1 gene polymorphisms and CYP3A4 isoenzyme activity on stent implantation complications among patients with an acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI). PATIENTS AND METHODS: Seventy-six patients (median age 63, range 37-91 years) with an ACS who underwent PCI were screened for CYP2C19 and ABCB1 gene polymorphisms with real-time polymerase chain reaction: CYP2C19*2, CYP2C19*17, and ABCB1 3435. CYP3A4 isoenzyme activity was determined by urine cortisol and 6-beta-hydroxycortisol levels. Stent implantation complications such as stent thrombosis (n=2) and restenosis (n=1) were observed among drug-eluting stent recipients. RESULTS: Low mean 6-beta-hydroxycortisol/cortisol ratio is indicative of impaired CYP3A4 activity and was associated with higher risk of thrombosis (b coefficient=0.022, SE 0.009, p=0.021 in the linear regression model). The increase in the length of the implanted stent was associated with higher risk of restenosis (b coefficient=0.006, SE=0.002, p=0.001 in the linear regression model). The presence of the CYP2C19*2 polymorphism did not affect the incidence of stent thrombosis (b coefficient=-1.626, SE=1.449, p=0.262 in the logistic regression model), nor did the CYP2C19*17 (b coefficient=-0.907, SE=1.438, p=0.528 in the logistic regression model) and ABCB1 3435 polymorphisms (b coefficient=1.270, SE=1.442, p=0.378 in the logistic regression model). CONCLUSION: We did not find evidence that the presence of CYP2C19*2, CYP2C19*17, and ABCB1 3435 polymorphisms may jeopardize the safety of stent implantation in patients with an ACS. Patients with low CYP3A4 isoenzyme activity may have increased risk of stent thrombosis.

Genetic Polymorphisms of Cytochrome P450 Enzymes and Transport Proteins in a Russian Population and Three Ethnic Groups of Dagestan.

AIM: The objective of this study was to investigate the prevalence of polymorphic markers of the CYP2C19, CYP2C9, CYP2D6, SLCO1B1, and ABCB1 genes among the three ethnic groups in Dagestan and compare it with the carrier frequency of these markers among the Russian population living in Moscow. METHODS: The study involved 186 healthy, unrelated, and chronic medication-free volunteers (53 males and 133 females) of the three ethnic groups in the Dagestan Republic: 46 Laks, 90 Avars, and 50 Dargins. Genotyping was performed using real-time polymerase chain reaction-based methods. The allelic prevalences of the three Dagestan peoples were compared with ethnic Russians from the Moscow region. RESULTS: Statistically significant differences for the following gene polymorphisms: CYP2C19*17, CYP2C9*3, ABCB1 (C3435T), SLCO1B1*5 were found between the Russian population and the three ethnic groups of the Dagestan republic. CONCLUSION: The data obtained from this study will help with prioritization genotyping in the region.

Urine metabolic ratio of omeprazole in relation to CYP2C19 polymorphisms in Russian peptic ulcer patients.

BACKGROUND: CYP2C19 is known to be the main enzyme of biotransformation of proton pump inhibitors (PPIs), whereas the CYP2C19 gene is highly polymorphic. Genotyping and phenotyping together represent more reliable data about patient's CYP2C19 activity. PURPOSE: The aim of the study was to investigate the applicability of urine metabolic ratio of omeprazole for CYP2C19 phenotyping in Russian peptic ulcer patients with different CYP2C19 genotypes. PATIENTS AND METHODS: A total of 59 patients (19 men and 40 women) aged 18-91 years (mean age 53.5±15.1 years) from four Moscow clinics who were diagnosed with an endoscopically and histologically proven peptic ulcer or had a history of endoscopically and histologically proven ulcers in the past were recruited. Peripheral venous blood (6 mL) was collected for DNA extraction, and real-time polymerase chain reaction was performed for the analysis of CYP2C19*2G681A (rs4244285), CYP2C19*3G636A (rs4986893) and CYP2C19*17C-806T (rs12248560) polymorphisms. Urine samples of patients were collected in the morning between 6 am and 9 am, before food or drug intake, after at least 3 days of twice daily (b.i.d.) omeprazole intake. Omeprazole and 5-hydroxyomeprazole concentrations in the urine were measured using high-performance liquid chromatography with mass spectrometry. RESULTS: Of the 59 patients, there were 27 (45.8%) extensive metabolizers (EMs; CYP2C19*1/*1), 16 (27.1%) ultrarapid metabolizers (UMs; CYP2C19*1/*17, CYP2C19*17/*17), 14 (23.7%) intermediate metabolizers (IMs; CYP2C19*1/*2, CYP2C19*2/*17, CYP2C19*3/*17) and two (3.4%) poor metabolizers (PMs; CYP2C19*2/*2). Median metabolic ratio (25%-75% percentiles) were 1.03 (0.69-1.36) for EMs, 1.95 (1.33-2.68) for UMs, 1.40 (0.78-2.13) for IMs+PMs and 1.26 (0.82-1.99) for the whole sample. A statistically significant difference in metabolic ratio (Mann-Whitney U test) was found between UMs and EMs (p=0.001) and in the multiple comparison Kruskal-Wallis test (p=0.005). CONCLUSION: We found a connection between particular CYP2C19 genotypes and urine metabolic ratio of omeprazole in Russian peptic ulcer patients. This method needs to be improved as in our modification it worked mainly for UMs and did not differentiate all patients according to omeprazole biotransformation activity.

Comparison of CYP2C9, CYP2C19, CYP2D6, ABCB1, and SLCO1B1 gene-polymorphism frequency in Russian and Nanai populations.

BACKGROUND: The efficiency and safety of drug therapy depends on the peculiarities of functioning of the P450 cytochrome group and transporting proteins. There are significant differences for single-nucleotide polymorphism (SNP) frequency. MATERIALS AND METHODS: We studied the peculiarities of P450 cytochrome polymorphisms, SLCO1B1 transporting protein, and P-glycoprotein carriage in healthy volunteers in the Nanai ethnic group living in Russia, and compared them to the carriage of SNPs in the Russian population according to literature data. RESULTS: After performing the real-time polymerase chain reactions on the samples from 70 healthy volunteers from the Nanai group, for the CYP2C9*2C430T polymorphism we determined 70 CC-genotype carriers. As for the CYP2C9*3A1075C polymorphism, we found 62 AA-genotype carriers and eight AC-genotype carriers. For the CYP2C19*2G681A polymorphism, we determined 39 GG-genotype carriers and 28 GA-genotype carriers, for the CYP2C19*3G636A polymorphism 58 GG-genotype carriers and 12 GA-genotype carriers, and for the CYP2C19*17C806T polymorphism 67 CC-genotype carriers and three CT-genotype carriers. For the CYP2D6*4G1846A polymorphism, the GG genotype had 68 carriers, and the GA genotype two carriers. For the ABCB1*6C3435T polymorphism, there were 19 CC-genotype carriers and 39 CT-genotype carriers. For the SLCO1B1*5T521C polymorphism, the TT genotype had 41 carriers and the CT genotype 25 carriers. The distribution of genotypes fitted the Hardy-Weinberg equilibrium for all the polymorphisms, except those of CYP2C9*2. There were also significant differences in allele frequencies for some polymorphisms between the Nanais and the Russians. CONCLUSION: In the Nanai population, there are polymorphisms connected with the decrease in safety and efficiency of drug therapy. Studying the ethnic differences might influence the determination of priority in the introduction of pharmacogenetic tests in clinical practice in different regions of Russia.