Vascular endothelial growth factor (VEGF) gene polymorphisms (rs699947, rs833061, and rs2010963) and psoriatic risk in South Indian Tamils.

BACKGROUND: Psoriasis is a chronic inflammatory disease of the skin. Vascular endothelial growth factor (VEGF), a pro-angiogenic factor, is involved in the pathogenesis of psoriasis. Being highly polymorphic, several SNPs of VEGF have been reported to be associated with increased risk of psoriasis. OBJECTIVES: We determined the association of VEGF gene polymorphisms with risk of psoriasis in South Indian Tamils. METHODS: 300 cases of psoriasis and 300 controls were recruited in this case-control study. Genotyping of SNPs of VEGF gene was done using Taqman 5' allele discrimination assay. Estimation of VEGF levels in plasma was done by ELISA. RESULTS: VEGF (rs2010963) polymorphism and the CTC haplotype were found to confer an increased risk of psoriasis. However, two other VEGF SNPs, rs833061, and rs699947, showed no association with psoriasis susceptibility. VEGF levels were higher in patients with psoriasis, as compared with controls and significantly correlated with disease severity. CONCLUSIONS: Our results indicate that VEGF (rs2010963) polymorphism and CTC haplotype of the VEGF SNPs (rs699947, rs833061, and rs2010963) confer an increased risk of psoriasis in the South Indian Tamil population. Plasma VEGF levels are higher in patients with psoriasis, as compared with controls and are significantly correlated with disease severity.

Role of CYP2C19 gene polymorphism in acute alcohol withdrawal treatment with loading dose of diazepam in a South Indian population.

PURPOSE: Alcohol dependence is a public health problem worldwide, commonly associated with withdrawal symptoms for which diazepam is a frequently used drug. We studied the effect of CYP2C19 gene polymorphisms on diazepam loading dose requirement and time to reversal of acute alcohol withdrawal symptoms. We also studied the influence of the polymorphism in this gene on the persistent symptoms after loading dose of diazepam. METHODS: Sixty-nine patients who reported to the psychiatry department with symptoms of alcohol withdrawal diagnosed by DSM-IV criteria were included for the study. A 10-mg loading dose of diazepam was administered iv after baseline assessment of withdrawal severity using CIWA-Ar scoring. The patients were assessed for improvement of the symptoms every two hourly and 20 mg oral diazepam was given based on improvement of symptoms. Genotyping for CYP2C19*2, CYP2C19*3 and CYP2C19*17 was done by PCR-RFLP and RT-PCR methods. RESULTS: The diazepam dose requirement as well as the time required for reversal of acute symptoms was not statistically different among the different genotype groups. Similarly, the frequency of patients with persistent symptoms after successful treatment of the acute episode was not different among the groups. However, the total diazepam dose requirement was influenced by baseline CIWA-Ar scores (adjusted OR 0.21, p = 0.026). In addition, the odds of treatment with a lower dose (10 mg) of diazepam were higher in smokers (adjusted OR 5.22, p = 0.025) and patients with other addiction (adjusted OR 9.26, p = 0.026). CONCLUSION: We found that CYP2C19 polymorphism did not have any significant effect on the diazepam dose requirement, time duration needed for successful treatment or on the persistent symptoms after loading dose of diazepam in South Indian population. However, diazepam dose requirement was influenced by baseline CIWA-Ar score, smoking status and other comorbid addictions.

Pattern of Adverse Drug Reactions Reported with Cardiovascular Drugs in a Tertiary Care Teaching Hospital.

BACKGROUND: Cardiovascular diseases (CVD) are one of the leading causes of non-communicable disease related deaths globally. Patients with cardiovascular diseases are often prescribed multiple drugs and have higher risk for developing more adverse drug reactions due to polypharmacy. AIM: To evaluate the pattern of adverse drug reactions reported with cardiovascular drugs in an adverse drug reaction monitoring centre (AMC) of a tertiary care hospital. SETTINGS AND DESIGN: Adverse drug reactions related to cardiovascular drugs reported to an AMC of a tertiary care hospital were included in this prospective observational study. MATERIALS AND METHODS: All cardiovascular drugs related adverse drug reactions (ADRs) received in AMC through spontaneous reporting system and active surveillance method from January 2011 to March 2013 were analysed for demographic profile, ADR pattern, severity and causality assessment. STATISTICAL ANALYSIS USED: The study used descriptive statistics and the values were expressed in numbers and percentages. RESULTS: During the study period, a total of 463 ADRs were reported from 397 patients which included 319 males (80.4%) and 78 females (19.6%). The cardiovascular drug related reports constituted 18.1% of the total 2188 ADR reports. In this study, the most common ADRs observed were cough (17.3%), gastritis (7.5%) and fatigue (6.5%). Assessment of ADRs using WHO-causality scale revealed that 62% of ADRs were possible, 28.2% certain and 6.8% probable. As per Naranjo's scale most of the reports were possible (68.8%) followed by probable (29.7%). According to Hartwig severity scale majority of the reports were mild (95%) followed by moderate (4.5%). A system wise classification of ADRs showed that gastrointestinal system (20.7%) related reactions were the most frequently observed adverse reactions followed by respiratory system (18.4%) related adverse effects. From the reported ADRs, the drugs most commonly associated with ADRs were found to be enalapril (17.5%), atorvastatin (14.9%), aspirin (8.4%) and metoprolol (8.4%). CONCLUSION: The cardiovascular drug related adverse effects constituted 18.1% of the total ADRs reported during the study period. Cough, gastritis, fatigue and myalgia by enalapril, aspirin, ß-blockers and atorvastatin respectively were found to be the most commonly reported ADRs among the cardiovascular drugs.

A study to explore the correlation of ABCB1, ABCG2, OCT1 genetic polymorphisms and trough level concentration with imatinib mesylate-induced thrombocytopenia in chronic myeloid leukemia patients.

PURPOSE: Imatinib mesylate is presently the first-line treatment for chronic myeloid leukemia (CML). Therapeutic drug monitoring (TDM) and pharmacogenetic screening is warranted for better management of imatinib therapy. The present study was framed to explore the influence of common drug transporter gene polymorphisms of ABCB1, ABCG2, OCT1 and trough level concentration on commonly occurring adverse events in CML patients treated with imatinib mesylate. METHODS: A total number of 111 patients in chronic phase (Philadelphia chromosome +ve) were included in the study. The plasma drug concentration of imatinib was estimated using LC-MS/MS method. RESULTS: The mean ± SD trough level concentration of imatinib mesylate was found to be 1430.7 ± 438.7 ng/ml. The trough level concentration at steady state (Cmin.ss) was significantly higher in patients with grade 2-4 thrombocytopenia compared with patients without the adverse event (P value 0.033). CONCLUSION: The drug level of imatinib in plasma correlates with the severity of thrombocytopenia, which adds to the utility of TDM in the management of CML patients.

Influence of Sokal, Hasford, EUTOS scores and pharmacogenetic factors on the complete cytogenetic response at 1 year in chronic myeloid leukemia patients treated with imatinib.

Imatinib mesylate is currently considered the first-line treatment for chronic myeloid leukemia (CML). Sokal, Hasford and EUTOS are the three major risk categorization scores available for CML patients. The present study aimed to explore the influence of three risk score, genetic polymorphisms of ABCB1, OCT1, ABCG2 and trough level concentration on complete cytogenetic response at 1 year and overall survival. The mean time period of follow-up was 53.05 months, and the overall survival was 94.6%. The Sokal score (P 0.014), Hasford score (P 0.016) and MDR1 C3435T (P 0.001) tend to influence the overall survival in the patients. The patients who had better overall survival had early complete cytogenetic response (P 0.0003). The ABCG2 C421A was the covariate which had correlation with the complete cytogenetic response. A perceptive approach incorporating pharmacogenetic evaluation with major risk categorization score at the initial stage will help in ensuring better treatment success in CML patients treated with imatinib.

Adverse drug reactions of imatinib in patients with chronic myeloid leukemia: A single-center surveillance study.

OBJECTIVE: To monitor the adverse drug reactions (ADRs) associated with imatinib treatment in patients with chronic myeloid leukemia (CML) in a tertiary care hospital. MATERIALS AND METHODS: The study was carried out by the Departments of Pharmacology and Medical Oncology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India. The study was carried out from March 2012 to February 2014. The ADRs were reported in a suspected Adverse Drug Reaction Reporting form, provided by the Central Drugs Standard Control Organization (CDSCO), Ministry of Health and Family Welfare, Government of India. The ADRs were analyzed for their pattern, causality and severity. RESULTS: A total of 326 ADRs from 81 patients were reported during the study period. The hematological toxicities were much more prominent than the non-hematological toxicities in this study. The prevalence of thrombocytopenia (21.17%) was higher compared with other reactions. Further analysis showed that most of the ADRs were mild to moderate in nature. The causality assessment revealed that the majority of the ADRs belonged to the possible category. CONCLUSION: The present study in a tertiary care hospital suggests that hematological toxicities are predominant in CML patients treated with imatinib mesylate. The blood and lymphatic system (38.96%) was the most affected, with imatinib therapy and thrombocytopenia (21.17%) being the most commonly encountered ADRs in the present study. Thorough monitoring of ADRs is warranted for better treatment outcomes.

Anticancer drug induced palmar plantar erythrodysesthesia.

BACKGROUND: Palmar plantar erythrodysesthesia (PPE) is a dose limiting toxicity of anticancer agents. In some cases it may mandate for discontinuation of anticancer agents. Evaluation of data of PPE among reported adverse drug reactions (ADRs) from the Department of Medical Oncology could quantify the burden. AIM: To evaluate and analyse the PPE among reported ADRs from medical Oncology. MATERIALS AND METHODS: The data of all cases of reported PPE were collected during January 2012 to September 2013 and were analysed with WHO causality assessment scale. The severity was clinically graded. The follow-up data regarding outcome of ADRs were also noted. RESULTS: During the study period of 21 months a total of 1418 ADRs have been reported from 1076 patients. Among them PPE was reported from 31 cases (2.9%). Majority (32.2%) of these patients were on chemotherapy for breast cancer. Patient's age ranged from 17 to 68 y and the median age was 50 y. There were 18 female (58%) and 13 male patients (42%). Capecitabine was the leading drug involved in PPE, reported with 20 cases (64.5%), and followed by docetaxel with 5 cases (16.1%). Majority (67.7%) of the reactions was categorized as certain and 64.5% was grade II severity clinically. CONCLUSION: Our findings show that PPE accounts for 2.9% of total reported ADRs from Medical Oncology during 21 months. Majority of the reactions were classified as certain. Capecitabine is commonly implicated drug.

Globalization of clinical trials - where are we heading?

The last decade has witnessed a greater transparency in clinical research with the advent of clinical trial registries. The aim of the study was to describe the trends in the globalization of clinical trials in the last five years. We performed an internet search using the WHO International clinical trials registry platform (WHO ICTRP) to identify the clinical trials conducted from January 2007 to December 31, 2011 among 25 countries. Among the 25 countries, the United States, Japan and Germany occupy the top positions in the total number of clinical trials conducted. Clinical trials in the US (36312) constituted 31.5% of the total number of trials performed during this period. However over a period of five years both US and Western Europe appear to show a decline, while the emerging countries show a rise in clinical trials registered. Among the emerging countries China, India and Republic of Korea are most active regions involved in clinical trials. Cancer, diabetes and respiratory diseases were most widely researched areas overall. Although the study confirms the transition in the clinical trials research towards emerging countries, the developed regions of the world still contribute to more than 70% of the trials registered worldwide.

Functional characterization of promoter region polymorphisms of human CYP2C19 gene.

CYP2C19 is an enzyme involved in the metabolism of several clinically important drugs. The variations in the CYP2C19 promoter region may alter the transcription of the gene by altering the interaction between the trans and cis-acting elements. In the present study, CYP2C19 promoter region with different variant alleles were cloned into a pGL-3 basic luciferase reporter vector and transfected into HepG2 cell lines. Subsequently, dual luciferase activity was measured to evaluate the activity of the promoter region. Gel shift assays with predicted binding sites for CCAAT displacement protein, activating transcription factor-2 and glucocorticoid receptor were performed. Results from this study indicate that few variations present in the putative cis-acting elements of the CYP2C19 promoter region such as -1442T>C, -779A>C and -98T>C -1498T>G and -828del>T alter the transcription of the gene. Specific binding with nuclear proteins was also observed in gel shift assays. This may account for the interindividual variations in gene expression and genotype dependant differences in gene transcription. The results also suggest the role of activating transcription factor-2 and CCAAT displacement repressor protein on CYP2C19 gene transcription.

Gene-gene interactions of drug metabolizing enzymes and transporter protein in the risk of upper aerodigestive tract cancers among Indians.

BACKGROUND: The combined genetic effects of single nucleotide polymorphisms may additively or synergistically contribute to the increased cancer risk. The interactions associated with xenobiotic metabolizing enzymes and transporter protein involved in the biotransformation and transport of xenobiotics could determine the functional outcomes over the independent effects of a single susceptibility gene in the risk of upper aerodigestive tract cancers. METHODS: The hospital-based case-control study evaluated CYP1A1 (*2A and *2C), CYP2E1 (*1B, *5B, and *6), GST (M1, T1, and P1) and ABCB1 3435C>T polymorphisms among 408 histopathologically confirmed cases and 220 controls using polymerase chain reaction based methods in an Indian population. RESULTS: The multivariate logistic regression analyses demonstrated potentially high risk gene-gene interactions with the concurrent deletions of the GSTT1 and GSTM1 genes and GSTP1 variant genotypes (OR 5.81; 95% CI 1.01-40.28), the deletions of GSTT1 and GSTM1 genotypes with variant genotypes of CYP1A1*2A (OR 8.21; 95% CI 1.91-49.48), GSTT1 and GSTM1 deficient genotypes along with CYP2E1*1B variant genotypes (OR 6.73; 95% CI 1.32-22.81), the polymorphic genotypes of ABCB1 and deficient GSTT1 (OR 6.08; 95% CI 2.21-16.76) and an enhanced risk with the combined variant genotypes of CYP1A1*2A, GSTT1 and ABCB1 (OR 11.14; 95% CI 2.70-46.02). CONCLUSION: The findings indicate that the interactions associated with various drug metabolizing enzymes and transporter protein exhibit high risk for UADT cancers than that ascribed to a single susceptible gene. This was particularly established among the polymorphic carriers of CYP1A1*2A, GSTT1 and ABCB1 genes in the population investigated.

Gene-environment interactions associated with CYP1A1 MspI and GST polymorphisms and the risk of upper aerodigestive tract cancers in an Indian population.

PURPOSE: Genetic risk to tobacco related cancers are associated with polymorphisms in CYP1A1 and GST, which are involved in the metabolic activation and detoxification of carcinogens. The genetic variations in these drug-metabolizing enzymes may alter the susceptibility to UADT cancers triggered by environmental exposures. The hospital-based case-control study evaluated the impact of combined CYP1A1 MspI and GST (M1 & T1) polymorphisms among the individuals exposed to environmental risk factors as modulators in the risk of UADT cancers in Tamilians, a population of south India. METHODS: The unrelated histopathologically confirmed 408 cases and 220 population-based controls matched by age and gender were genotyped for CYP1A1 MspI, GSTM1 and GSTT1 polymorphisms using PCR based methods. To investigate the potential gene-environment interactions, analyses were carried out stratifying by smoking and tobacco chewing status using SPSS software. RESULTS: The combination of genes and environment interactions by stratified analyses revealed significant interactions among the habitual tobacco smokers (CYP1A1 MspI & GSTM1 null: OR 14.06; 95% CI 3.90-50.68, CYP1A1 MspI & GSTT1 null: OR 33.28; 95% CI 4.24-261.19) and tobacco chewers (CYP1A1 MspI & GSTM1 null: OR 20.51; 95% CI 6.77-62.13, CYP1A1 MspI & GSTT1 null: OR 79.35; 95% CI 10.40-605.55) on the multiplicative scale. CONCLUSION: Our findings have indicated that the individuals polymorphic for CYP1A1 MspI either with GSTM1 null or with GSTT1 null genotypes revealed an increased risk for UADT cancers than that ascribed to a single susceptible gene among the tobacco users in the population [single gene risk among smokers and chewers, respectively, for CYP1A1 MspI (OR 6.43; 95% CI 3.69-11.21); (OR 10.24; 95% CI 5.95-17.60), GSTM1*0 (OR 3.77; 95% CI 1.94-7.37); (OR 7.97 95% CI 4.10-15.76) and GSTT1*0 (OR 6.95 95% CI 2.88-16.77); (OR 25.83 95% CI 7.78-85.76).

A single-nucleotide polymorphism in the MDR1 gene as a predictor of response to neoadjuvant chemotherapy in breast cancer.

BACKGROUND: The single-nucleotide polymorphism (SNP) 3435C > T in exon 26 of the MDR1 gene has been shown to correlate with the functioning of P-glycoprotein. We studied the frequency of SNP in exon 26 of the MDR1 gene in breast cancer and its role in predicting response to neoadjuvant chemotherapy in breast cancer. PATIENTS AND METHODS: Ninety-six patients with locally advanced breast carcinoma were enrolled. Genotyping of exon 26 of the MDR1 gene was performed, and computed tomography scans were performed before and after neoadjuvant chemotherapy. Response to 3 cycles of the 5-fluorouracil/doxorubicin/ cyclophosphamide (FAC) regimen was assessed. The prevalence of SNP was compared with that of historical controls. Association of the response was compared with the genotypes. RESULTS: The frequency of genotypes was different from that of healthy sex-matched historical controls. Prevalence of TT genotype was significantly increased in breast cancer patients (P = .025). The patients with TT genotype had 2.26 times the chance of responding to neoadjuvant chemotherapy when compared with patients with the CC genotype (P = .44). CONCLUSION: Significantly higher prevalence of 3435TT genotype in exon 26 of the MDR1 gene in patients with breast cancer might suggest the possibility of increased breast cancer susceptibility. The genotypes did not show any significant association to response to chemotherapy in the population studied.

CYP1A1 polymorphisms and the risk of upper aerodigestive tract cancers in an Indian population.

BACKGROUND: The inter-individual differences in upper aerodigestive tract (UADT) cancer risk may be partly attributed to the polymorphic variability in the CYP1A1 gene that is involved in the metabolic activation of xenobiotics to carcinogenic reactive metabolites. METHODS: The hospital-based case-control study evaluated CYP1A1*2A and CYP1A1*2C polymorphisms in 408 histopathologically confirmed cases and 220 controls using polymerase chain reaction-restriction fragment length polymorphism methods. RESULTS: The multivariate logistic regression analyses demonstrated that CYP1A1 *1A/*2A (odds ratio [OR] 1.76; 95% Confidence interval [CI] 1.19-2.60) and *2A/*2A (OR 2.83; 95% CI 1.43-5.61) genotypes were significantly associated with increased risk for UADT cancers. The gene-environment interaction analyses revealed a significant interaction among tobacco smokers and chewers carrying CYP1A1*2A mutant genotypes on the multiplicative scale. CONCLUSION: CYP1A1*2A polymorphic genotypes are associated with an enhanced risk to UADT cancers, in particular, among the habitual tobacco smokers and chewers carrying mutant genotypes in the Tamilians of the Indian population.

ABCB1 genetic polymorphism and risk of upper aerodigestive tract cancers among smokers, tobacco chewers and alcoholics in an Indian population.

BACKGROUND AND OBJECTIVE: Upper aerodigestive tract (UADT) cancers are associated with the tobacco use and alcohol consumption. Certain toxins and carcinogens causing UADT cancers are found to be substrates of polymorphic ABCB1 gene encoded P-glycoprotein efflux pump. This study investigates the association between ABCB1 gene polymorphism at exon 26 (3435C>T) and risk to UADT cancers in Tamilians, a population of south India. METHODS: The study included 219 unrelated histopathologically confirmed cases and 210 population-based controls. Genomic DNA was extracted from peripheral leukocytes and genotyped for ABCB1 3435C>T polymorphism by PCR-restriction fragment length polymorphism method. RESULTS: The multivariate logistic regression analyses demonstrated that the homozygous ABCB1 TT genotype was significantly associated with an overall increased risk for developing UADT cancers [odds ratio (OR): 2.53; 95% confidence interval (CI): 1.28-5.02]. Further, the determination of gene-environment interaction by stratified analyses have revealed a significant interaction between the smoking and homozygous TT genotype [(OR: 7.52; CI: 1.50-37.70) and (OR: 16.89; CI: 3.87-73.79) for 11-20 and >20 pack-years, respectively]. The strongest interaction was observed among the regular tobacco chewers (OR: 45.29; CI: 8.94-130.56) homozygous for TT genotype. No suggestion, however, of an interaction between the genotypes and the alcohol consumption on the multiplicative scale was made. CONCLUSION: The ABCB1 gene polymorphism at exon 26 (3435C>T) may be one of the risk factors for susceptibility to UADT cancers. Furthermore, the significant interaction among habitual smokers and tobacco chewers, homozygous for TT genotype modulates the risk to UADT cancers in the Tamilian population of south India.