Association of polymorphisms in TRAIL1 and TRAILR1 genes with susceptibility to lymphomas.

The TRAILR1/TRAIL system is implicated in the induction of the extrinsic apoptotic pathway and constitutes an emerging target in cancer therapeutics. The objective of this study is to assess lymphoma risk associated with certain polymorphisms in TRAILR1 and TRAIL1 genes. DNA was extracted from 381 subjects (190 lymphoma cases and 191 matched controls) and genotyped for polymorphisms rs20576, rs2230229 and rs20575 in TRAILR1 and rs12488654 in TRAIL gene. In contrast to TRAILR1 polymorphisms, the genotype distribution of rs12488654 in TRAIL gene was different between cases and controls, A allele carriers (CA/AA) being much more common in the cases with different lymphoma types (follicular, 45 %; diffuse large B cell, 45.2 % and Hodgkin lymphomas, 40 %) than in controls (15.7 %) (odds ratio (OR), 3.5; CI, 2.1­5.9; p<0.001; OR, 3.5; CI, 1.6­7.9; p=0.001; OR, 2.9; CI, 1.1­7.5; p=0.027, respectively). This effect was consistently independent of the association with the TRAILR1 polymorphisms studied, as demonstrated by linkage disequilibrium and haplotype analyses. This study is the first one to report an association between a TRAIL polymorphism and lymphoma risk and suggests a possible role of TRAIL in B cell lymphomagenesis.

Polymorphisms in xenobiotic metabolizing genes (EPHX1, NQO1 and PON1) in lymphoma susceptibility: a case control study.

BACKGROUND: The interplay between genetic susceptibility and carcinogenic exposure is important in the development of haematopoietic malignancies. EPHX1, NQO1 and PON1 are three genes encoding proteins directly involved in the detoxification of potential carcinogens. METHODS: We have studied the prevalence of three functional polymorphisms affecting these genes rs1051740 EPHX1, rs1800566 NQO1 and rs662 PON1 in 215 patients with lymphoma and 214 healthy controls. RESULTS: Genotype frequencies for EPHX and NQO1 polymorphisms did not show any correlation with disease. In contrast, the GG genotype in the PON1 polymorphism was found to be strongly associated with the disease (15.3% vs. 4.7%; OR = 3.7 CI (95%): 1.8-7.7; p < 0.001). According to the pathological diagnosis this association was related to follicular (p = 0.004) and diffuse large B-cell (p = 0.016) lymphomas. CONCLUSIONS: Despite the fact that further confirmation is needed, this study shows that the PON1 GG genotype in rs662 polymorphism could be a risk factor for B-cell lymphomas.

Role of GSTT1 and M1 null genotypes as risk factors for B-cell lymphoma: influence of geographical factors and occupational exposure.

The interrelationship between genetic susceptibility and carcinogenic exposure is important in the development of haematopoietic malignancies. Both factors need to be considered to enable assessment of disease risk associated with a given individual under certain environmental conditions. GSTT1 and GSTM1 are two genes whose proteins are involved in the detoxification of potential carcinogens. We have studied the prevalence of GSTT1 and GSTM1 null polymorphisms using a novel PCR multiplex protocol in a group of 158 patients with B-cell lymphoma (BCL, 138 with non-Hodgkin lymphoma and 20 with Hodgkin lymphoma) and 214 healthy controls. A questionnaire regarding occupational exposure and lifestyle factors was also completed by both groups. GSTM1 null genotype showed no significant differences between patients and controls (46.9% and 55.6%, respectively). In contrast, GSTT1 null genotype was observed in 25.3% of patients and 15.4% of controls (P=0.013; OR=1.85; CI (95%):1.11-3.09), suggesting a role for the GSTT1 null genotype in the development of BCL. This effect was even more evident in females (27.5% vs. 14%: P=0.014). No significant association was observed between GST genotypes and disease risk in relation to smoking or occupational exposure.

Genotyping of six clopidogrel-metabolizing enzyme polymorphisms has a minor role in the assessment of platelet reactivity in patients with acute coronary syndrome.

OBJECTIVE: To evaluate the contribution of six polymorphisms to the platelet reactivity in patients with acute coronary syndrome (ACS) treated with clopidogrel. METHODS: Cross-sectional study of 278 consecutive patients with ACS. Detailed clinical information for each patient was collected and genotypes (CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP2C19*17, CYP3A4*1B, and PON1-Q192R) were evaluated with TaqMan® and KASPar® assays. Platelet reactivity was measured with VerifyNow®. RESULTS: Mean age of patients was 66±11 years and 182 (65.5%) patients presented ACS without ST-segment elevation. A total of 206 (74.1%) patients presented poor response to clopidogrel (PRC). CYP2C19*2 polymorphism (p=0.038) was associated with PRC in the univariate setting. In the multiple logistic regression analysis, the risk factors for PRC were the presence of CYP3A4*1B allele (odds ratio [OR] 4.03; 95% confidence interval [CI] 1.01-16.34), age (OR 1.43; 95% CI 1.03-2.00), and body mass index (OR 4.05; 95% CI 1.21-13.43), whereas elevated hemoglobin was a protective factor. Discrimination of PRC through the model that included the six polymorphisms added modest information to the model based on clinical variables (C statistic difference 3.9%). CONCLUSION: CYP3A4*1B allele may be an independent determinant of PRC in patients with ACS, although the variability in response to clopidogrel explained by the six polymorphisms is poor when compared to clinical variables.