Risk effects of GST gene polymorphisms in patients with acute myeloid leukemia: a prospective study

Ile105Val polymorphism in the GSTP1 gene is associated with susceptibility to acute myeloid leukemia: an updated systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Several genetic variations are associated with acute myeloid leukemia (AML) susceptibility, including the GSTP1 Ile105Val polymorphism. Even with the existing meta-analysis conducted on the topic, no consensus has been reached since none of the studies available performed in-depth data analysis. Hence, we performed an updated systematic review and meta-analysis in this paper to obtain more precise estimates.

MATERIALS AND METHODS

We searched various databases and calculated the odds ratio (OR) and 95% confidence interval (CI) to examine whether the GSTP1 Ile105Val polymorphism is associated with AML susceptibility. Further statistical analysis was also done to obtain more accurate and reliable findings.

RESULTS

A total of 15 studies are included in the systematic review, but only 9 were included in the meta-analysis due to the studies deviating from the Hardy-Weinberg equilibrium. The analysis showed significantly increased susceptibility to AML in the allelic, co-dominant, and recessive models. Furthermore, subgroup analysis noted increased AML susceptibility in the non-Asian population. Comparing the proportions of the genotypes and alleles showed a significantly higher proportion of the Val/Val genotype and Val allele in the non-Asian cohort.

CONCLUSION

The GSTP1 Ile105Val polymorphism is significantly associated with AML susceptibility, especially among non-Asians. Further investigation should be performed to strengthen the current results.

In Vitro Low-Bortezomib Doses Induce Apoptosis and Independently Decrease the Activities of Glutathione S-Transferase and Glutathione Peroxidase in Multiple Myeloma, Taking into Account the GSTT1 and GSTM1 Gene Variants

BACKGROUND

Multiple myeloma (MM) is a malignancy derived from plasma cells. Bortezomib affects the concentration of reduced glutathione (GSH) and the activity of glutathione enzymes. The aim of our study was to analyze deletion (null/present) variants of GSTT1 and GSTM1 genes and their association with the levels of glutathione and its enzymes in bortezomib-treated cell cultures derived from MM patients.

MATERIALS AND METHODS

This study included 180 individuals (80 MM patients and 100 healthy blood donors) who were genotyped via multiplex PCR (for the GSTT1/GSTM1 genes). Under in vitro conditions, MM bone marrow cells were treated with bortezomib (1-4 nM) to determine apoptosis (via fluorescence microscopy), GSH concentration, and activity of glutathione enzymes (via ELISA).

RESULTS

Bortezomib increased the number of apoptotic cells and decreased the activity of S-glutathione transferase (GST) and glutathione peroxidase (GPx). We found significant differences in GST activity between 1 nM (GSTT1-null vs. GSTT1-present), 2 nM (GSTT1-null vs. GSTT1-present), and 4 nM (GSTM1-null vs. GSTM1-present) bortezomib: 0.07 vs. 0.12, p = 0.02; 0.06 vs. 0.10, p = 0.02; and 0.03 vs. 0.08, p = 0.01, respectively.

CONCLUSIONS

Bortezomib affects the activities of GST and GPx. GST activity was associated with GSTT1 and GSTM1 variants but only at some bortezomib doses.

Association Between the Individual and Combined Effects of the GSTM1 and GSTT1 Polymorphisms and Risk of Leukemia: A Meta-Analysis

Background: Fourteen meta-analyses reported the individual effects of the GSTM1 and GSTT1 polymorphisms on leukemia risk. However, over 40 studies were not included in previously published meta-analyses. Moreover, one key aspect was that previous meta-analyses did not conduct the false-positive test on the aforementioned issues. Furthermore, previous meta-analyses did not observe the combined effects of GSTM1 present/null and GSTT1 present/null polymorphism with leukemia risk. Therefore, we conducted the current study to further analyze these associations.

Objectives: This study aimed to investigate the association between the individual and combined effects of the GSTM1 present/null and GSTT1 present/null polymorphisms and the risk of leukemia.

Methods: A meta-analysis was performed applying Meta-analyses of Observational Studies in Epidemiology (MOOSE) guidelines. Moreover, false-positive report probability (FPRP) and Bayesian false discovery probability (BFDP) were applied to investigate the false-positive results.

Results: The individual GSTM1 and GSTT1 null genotypes and combined effects of the two genes were associated with a significantly increased leukemia risk in overall and several subgroup analyses, such as Asians, Caucasians, and so on. Then, further analysis was conducted using FPRP and BFDP. Significant associations were considered as “positive” results on the GSTM1 null genotype with leukemia risk in overall populations (FPRP < 0.001 and BFDP = 0.006), Asians (FPRP < 0.001 and BFDP < 0.001), and East Asian population (FPRP < 0.001 and BFDP = 0.002). For the GSTT1 null genotype, significant associations were regarded “positive” results in overall populations, acute myeloid leukemia (AML), Asians, and East Asian population. For the combined effects of the GSTM1 and GSTT1 polymorphisms, significant associations were also considered “positive” results in the overall analysis of Asians, Indians, and East Asian population.

Conclusion: This study strongly indicates that the individual GSTM1 and GSTT1 null genotypes and combined effects of the two genes are associated with increased leukemia risk in Asians, especially in the East Asian population; the GSTT1 null genotype is associated with increased AML risk; the combined effects of the two genes are associated with increased leukemia risk in Indians.

Influence of genetic polymorphisms in glutathione-S-transferases gene in response to imatinib among Brazilian patients with chronic myeloid leukemia

Polymorphism in metabolizing enzymes can influence drug response as well as the risk for adverse drug reactions. Nevertheless, there are still few studies analyzing the consequence of polymorphisms for the Glutathione-S-transferases (GST) gene to drug response in chronic myeloid leukemia (CML). This study reports, the influence of GSTP1*B and GSTT1/GSTM1null polymorphisms in response to imatinib in CML patients in a Brazilian population. One hundred thirty-nine CML patients from the Clinical Hospital of Goiânia, Goiás, Brazil, treated with imatinib were enrolled in this study. Genotyping of GSTT1 and GSTM1 genes deletions were performed by qPCR and of GSTP1 gene was performed by RFLP-PCR. The frequency of GSTP1*1B, GSTT1 and GSTM1null polymorphisms were determined for all patients. The influence of each patient's genotypes was analyzed with the patient's response to imatinib treatment. Brazilian CML patients revealed GSTT1 and GSTM1 genes deletions. GSTT1 deletion was found in 19.3% of patients and GSTM1 deletion in 48.7% of patients with CML. GSTT1/GSTM1 deletion was found in 11.7% in Brazilian CML patients. The "G allele" of GSTP1*B, is associated with later cytogenetic response in imatinib therapy. While, the gene presence combined with GG genotype (GSTM1 present/GSTPI-GG) conferred a tend to a later cytogenetic response to patients. GSTP1*B and GSTT1/GSTM1null polymorphisms influence treatment response in CML. Brazilian CML patients presenting GSTP1 AA/AG genotypes alone and in combination with GSTT1 null reach the cytogenetic response faster, while patients presenting GSTP1-GG and GSTMI positive genotypes may take longer to achieve cytogenetic response. As a result, it allows a better prognosis, with the use of an alternative therapy, other than reducing treatment cost.

Genetic Polymorphism of GSTP1, GSTM1 and GSTT1 Genes and Susceptibility to Chronic Myeloid Leukaemia

BACKGROUND

The development of cancer results from an imbalance between exposure to carcinogens and the capacity of various enzyme systems engaged in activation or in the detoxification of xenobiotics. The aim of the present study is to investigate the association of GSTP1, GSTM1 and GSTT1 gene polymorphisms in susceptibility to Chronic Myeloid Leukaemia (CML).

METHODS

A total of 200 CML patients and 100 controls were enrolled in a case-control study with GSTM1 and GSTT1 analysis with PCR and GSTP1 analysis with PCR-RFLP.

RESULTS

The GSTT1 null genotype was significantly higher among CML patients suggesting that this genotype is associated with an increased risk of CML. It was found in 42% of cases as compared with 21% of the controls, (OR =2.78, 95% CI: 1.59 - 4.85; p-value =0.000). The presence of the GSTT1 genotype may thus be considered a protective factor for CML. The frequency of individuals carrying GSTM1 null genotype was slightly higher in the control group but this difference was not statistically significant. The GSTM1 null genotype was present in 35% of control cases and 34% of the CML patients, (OR=0.975, 95%CI: 0.58-1.58;p-value=0.863). Individuals with a combined GSTM1 null/GSTT1null genotype had an estimated 2.85-fold increased risk of CML, but no associated risk between GSTP1 Ile 105 Val polymorphism and CML was found (OR=1.99, 95% CI: 0.40 - 9.32; p-value = 0.417).

CONCLUSIONS

No association between GSTP1 and GSTM1 with susceptibility to CML was found. GSTT1 genotype may be a protective factor for CML, while the null genotype shows association with developing CML.<br />.

The Association of GSTT1, GSTM1, and TNF-α Polymorphisms With the Risk and Outcome in Multiple Myeloma

Oxidative stress and systemic inflammation are closely linked with increased risk of cancer development. Tumor necrosis factor alpha (TNF-α) is one of the pro-inflammatory cytokines. Glutathione S-transferases (GSTs) are enzymes involved in oxidative stress handling. Polymorphisms of genes encoding mentioned molecules may potentially influence the risk and the outcome in neoplastic diseases. Multiple myeloma (MM) is a hematological malignancy characterized by clonal, atypical plasma cell proliferation. In the present study we investigated the association of deletion polymorphisms in GSTT1/GSTM1 genes and single nucleotide polymorphisms (SNPs) in the TNF-α gene at positions −308/−238 with the risk and outcome in MM and sensitivity to bortezomib under in vitro conditions. One hundred newly diagnosed MM patients and 100 healthy blood donors were genotyped by means of multiplex PCR (for GSTs) and PCR-RFLP (for TNF-α). In a subgroup of 50 MM patients, bone marrow cells were treated with bortezomib in vitro. Patients with −238GA+AA or GSTT1-null genotypes had 2.0 (p = 0.002) or 2.29 (p = 0.013) fold increased risk of MM. The interaction effects and risk of MM were observed in GSTT1/GSTM1-null (OR = 2.82, p = 0.018), −308/−238GA+AA (OR = 5.63, p < 0.001), as well as in all combinations of −308 with GSTs. The −308/−238GA+AA genotypes in comparison to GG were associated with earlier MM onset−61.14 vs. 66.86 years (p = 0.009) and 61.72 vs. 66.52 years (p = 0.035), respectively. Patients with GSTM1-present had shorter progression-free-survival (15.17 vs. 26.81 months, p = 0.003) and overall-survival (22.79 vs. 34.81 months, p = 0.039) compared with GSTM1-null. We did not observe relationship between response rate and studied polymorphisms. The in vitro study revealed significantly higher number of apoptotic cells at 12 nM of bortezomib in GSTT1-present, GSTM1-null/present, −308GG and −238GG/GA+AA genotypes. Our findings comprise large analysis of studied polymorphisms in MM.

In vitro and in vivo studies of oxidative stress responses against acrylamide toxicity in zebrafish

Acrylamide (AA) is widely used in soil stabilization, water treatment, and industrial products and found in certain foods; however, its toxicity is an expanding global concern. Thus, to reveal the mechanisms involved in the development of, or protection from AA-induced toxicity has important significance. For this purpose, here we explored the intracellular stress response signaling pathways activated by AA exposure in zebrafish model. BRF41 cells derived from zebrafish were exposed to AA, and changes in the expression levels of 31 genes, including endoplasmic reticulum stress response-, oxidative stress response-, osmotic stress response-, and DNA damage and repair-related genes, were analyzed by PCR array. 12 genes upregulated in AA-exposed BRF41 cells were analyzed in zebrafish larvae by quantitative real time PCR, and the expression of all tested oxidative stress response-related genes was upregulated. Spatial expression patterns of these genes were visualized and found that their expression was upregulated and ectopically induced. In addition, AA-induced toxicity in BRF41 cells and the expression of glutathione S-transferase pi 1 (gstp1) in zebrafish larvae were reduced by N-acetylcysteine. Furthermore, inhibition of Gst activity enhanced AA toxicity. From these results, we concluded that the elicited oxidative stress response critically contributes to the protection from AA-induced toxicity.

Genetic variants of glutathione S-transferase and the risk of acute myeloid leukemia in a Saudi population

Objective

This study aims to investigate the genetic association of acute myeloid leukemia and glutathione S-transferase (GST) gene polymorphisms in a Saudi population.

Method

100 AML cases and 100 healthy controls were recruited from the Riyadh regional hospital. In the GST gene, GSTM1 and GSTT1 variants were genotyped by multiplex PCR, and GSTP1 variants were genotyped by PCR-RFLP analysis. Statistical analysis between AML cases and controls included anthropometric measurements and evaluation of the genotypic and allelic frequencies.

Result

The null genotypes of GSTM1 and GSTT1 showed no association with AML [OR 0.56 (0.26–1.19); p = 0.31 and OR 0.65 (0.37–1.16); p = 0.14]. Similarly, the GSTP1 genotype and allele frequencies did not indicate any association with AML [GG + AG vs. AA: OR 0.75 (0.43–1.31) and p = 0.32; GG vs. AA: OR 1.73 (0.55–5.44) and p = 0.34; G vs. A: OR 0.95 (0.61–1.46) and p = 0.82]. Further, a haplotype analysis between AML cases and controls did not show any positive association (p < 0.05).

Conclusion

In conclusion, there was no statistical association of the genotypes and alleles in GSTM1, GSTT1, and GSTP1 with AML. Our results confirm the negative association of the investigated genetic markers with susceptibility to AML. Further association studies would be required in different ethnic populations to facilitate a meta-analysis in the future. Our findings suggest that the GST gene has no role in the pathogenesis of AML in patients from Saudi Arabia.

Demographic and Clinical Characteristics of Adult Acute Myeloid Leukemia--Tertiary Care Experience

BACKGROUND

Acute myeloid leukemia (AML) is an acquired clonal frequent malignant disorder of myeloid progenitor cells. Our aim was to study demographical and clinicopathological features of adult Pakistani AML patients at presentation.

MATERIALS AND METHODS

In this single centre study extending from January 2010 to December 2014, data were retrieved from the patient records with a predetermined performa and analyzed with SPSS version 22.

RESULTS

Overall 125 patients were diagnosed at our institution with de novo AML during the study period. There were 76 males and 49 females (ratio 1.5:1), with an age range between 15 and 85 years and a mean age of 38.8±20.1 years. The major complaints were fever (72.8%), generalized weakness (60%), bleeding (37.6%) and dyspnea (12%). Physical examination revealed pallor in 56.8%, splenomegaly and hepatomegaly in 16% and 12.8%, respectively, and lymphodenopathy in 10.4%. The mean hemoglobin was 8.19±2.12g/dl with a mean MCV of 86.0±9.83 fl, a mean total leukocyte count of 43.1±68.5x109/l, an ANC of 3.09±6.66x109/l and a mean platelet count of 62.3±78.6x109/l.

CONCLUSIONS

AML in Pakistani patients is seen in a relatively very young population with male preponderance, compared with the west. However, clinico-pathological features appear comparable to published data.

Cigarette smoking, dietary habits and genetic polymorphisms in GSTT1, GSTM1 and CYP1A1 metabolic genes: A case-control study in oncohematological diseases

AIM

To analyze the association between oncohematological diseases and GSTT1/GSTM1/CYP1A1 polymorphisms, dietary habits and smoking, in an argentine hospital-based case-control study.

METHODS

This hospital-based case-control study involved 125 patients with oncohematological diseases and 310 control subjects. A questionnaire was used to obtain sociodemographic data and information about habits. Blood samples were collected, and DNA was extracted using salting out methods. Deletions in GSTT1 and GSTM1 (null genotypes) were addressed by PCR. CYP1A1 MspI polymorphism was detected by PCR-RFLP. Odds ratio (OR) and 95%CI were calculated to estimate the association between each variable studied and oncohematological disease.

RESULTS

Women showed lower risk of disease compared to men (OR 0.52, 95%CI: 0.34-0.82, P = 0.003). Higher levels of education (> 12 years) were significantly associated with an increased risk, compared to complete primary school or less (OR 3.68, 95%CI: 1.82-7.40, P < 0.001 adjusted for age and sex). With respect to tobacco, none of the smoking categories showed association with oncohematological diseases. Regarding dietary habits, consumption of grilled/barbecued meat 3 or more times per month showed significant association with an increased risk of disease (OR 1.72, 95%CI: 1.08-2.75, P = 0.02). Daily consumption of coffee also was associated with an increased risk (OR 1.77, 95%CI: 1.03-3.03, P = 0.03). Results for GSTT1, GSTM1 and CYP1A1 polymorphisms showed no significant association with oncohematological diseases. When analyzing the interaction between polymorphisms and tobacco smoking or dietary habits, no statistically significant associations that modify disease risk were found.

CONCLUSION

We reported an increased risk of oncohematological diseases associated with meat and coffee intake. We did not find significant associations between genetic polymorphisms and blood cancer.

GSTM1 and GSTP1 Genetic Polymorphisms and Their Associations With Acute Lymphoblastic Leukemia Susceptibility in a Jordanian Population

The genetic variations between different individuals in the xenobiotic detoxifying enzyme activity were shown to change susceptibility to acute lymphoblastic leukemia (ALL). The current study aimed to assess the association of GSTM1 and GSTP1 genetic polymorphisms with the susceptibility of ALL. This case-control study (N=264) involved 88 Jordanian ALL children and 176 healthy controls from an ethnically homogenous Jordanian children population. The polymerase chain reaction assay was used to genotype GSTM1 (null/present) and the polymerase chain reaction-restriction fragment length polymorphism technique was also applied to detect the genetic polymorphisms of GSTP1 (Ile105Val) at the rs1695 position. The biallelic analysis revealed that there was no association between GSTM1 double-null genotype and ALL (P=0.57). However, there was a strong association between GSTP1 (Ile105Val) polymorphism genotypes and alleles within GSTP1 gene and ALL (P=0.00049 and 0.000044, respectively). A combination between GSTM1 double-null genotype and rs1695 also showed an association with ALL (P=0.042). This study showed that the rs1695 single nucleotide polymorphism within the GSTP1 gene is strongly implicated in ALL among Jordanian children with ALL. These results indicate that genetic variants of GSTP1 gene influence the risk of developing ALL in the Jordanian children of Arab ancestry.

Acute Myeloid Leukemia: Clinical Spectrum of 125 Patients

BACKGROUND

Acute myeloid leukemia is an acquired clonal heterogeneous stem cell disorder. Hence, various parameters are sought out to categorize this disease into subtypes, so that as a consequence specific treatment modalities can be offered. Conventionally, the practically used method for classification utilizes French American British (FAB) criteria based on morphology and cytochemistry. The aim of present study was to determine the current spectrum of AML sub types in patients in Karachi.

MATERIALS AND METHODS

This single centre cross sectional study was conducted at Liaquat National Hospital, Karachi, extending from January 2010 to December 2014. Data were retrieved from archives were analyzed with SPSS version 22.

RESULTS

A total of 125 patients were diagnosed at our institution with de novo AML during five years period, 76 males and 49 females. Median age was 34.5 years. AML-M1 was the predominant FAB subtype (23.2%) followed by M2 (18.4%), M3 and M4 (16% each), M0 (14.4%), M5 (7.2%), M6 (3.2%) and M7 (1.6%).

CONCLUSIONS

AML in Pakistani patients is seen in a relatively young population. The most common FAB subtype observed in our study was acute myeloblastic leukemia, without maturation (M1).

From Six Gene Polymorphisms of the Antioxidant System, Only GPX Pro198Leu and GSTP1 Ile105Val Modulate the Risk of Acute Myeloid Leukemia

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.

Glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and acute leukemia risk in Asians: a meta-analysis

The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and risk of acute leukemia in Asians remains controversial. This study was therefore designed to evaluate the precise association in 23 studies identified by a search of PubMed and several other databases, up to December 2013. Using random or fixed effects models odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Heterogeneity across studies was assessed, and funnel plots were constructed to test for publication bias. The meta-analysis showed positive associations between GST polymorphisms (GSTM1 and GSTT1 but not GSTP1) and acute leukemia risk [(OR=1.47, 95% CI 1.18-1.83); (OR=1.32, 95% CI 1.07-1.62); (OR=1.01, 95% CI 0.84-1.23), respectively] and heterogeneity between the studies. The results suggested that the GSTM1 null genotype and GSTT1null genotype, but not the GSTP1 polymorphism, might be a potential risk factors for acute leukemia. Further well-designed studies are needed to confirm our findings.

CAT, GPX1, MnSOD, GSTM1, GSTT1, and GSTP1 genetic polymorphisms in chronic myeloid leukemia: a case-control study

Oxidative damage at the DNA level may be promoted by high levels of reactive oxygen species (ROS), leading to genomic instability and increased neoplastic risk. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) enzymes are implicated in the prevention of DNA damage by ROS. The aim of the study was to investigate the relationships between CAT C262T, GPX1 Pro198Leu, MnSOD Ala16Val, GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms and the risk of CML. No association was observed between CML and variant genotypes of GPX1, MnSOD, GSTM1, and GSTT1 polymorphisms in any of the investigated cases. Our study suggests that the homozygous variant genotype of the GSTP1 Ile105Val gene polymorphisms may be associated with the risk of developing CML (OR = 2.5; 95% CI = 1.08–5.7; P value = 0.02), while the heterozygous genotype of the CAT C262T polymorphism seems to have a protective effect against CML (OR = 0.59, 95% CI = 0.39–0.89, P value = 0.01). In most cases, no association was found between laboratory parameters and prognostic factors and the variant genotype of investigated gene polymorphisms. We concluded that CAT, GPX, MnSOD, GSTM1, and GSTT1 gene polymorphisms are not associated with the risk of CML. Variant genotype of the GSTP1 Ile105Val gene polymorphisms may contribute to the risk of developing CML.

Glutathione S-transferase gene polymorphisms and susceptibility to acute myeloid leukemia: meta-analyses

OBJECTIVE

A large body of evidence has shown the possible relevance of polymorphisms of the genes that encode glutathione S-transferase μ, π and θ (GSTM1, GSTP1 and GST1, respectively) to the susceptibility of acute myeloid leukemia, but the exact association still remains uncertain. Therefore, we performed a meta-analysis to derive a more precise estimation of the relationship.

METHODS

A comprehensive literature search of PubMed and Web of Knowledge electronic databases was conducted to collect relevant studies until 20 February 2014. References of the retrieved articles were also screened. The extracted data were statistically analyzed, and pooled odds ratios with 95% confidence intervals were calculated to estimate the association strength using Review Manager version 5.2.

RESULTS

Twenty-nine studies were included in the meta-analysis. The pooled analyses revealed that the GSTM1-null genotype was associated with an increased risk of acute myeloid leukemia in East Asians (P = 0.01; odds ratio = 1.22; 95% confidence interval = 1.05-1.42), and GSTT1-null genotype in Caucasians (P < 0.0001; odds ratio = 1.48; 95% confidence interval = 1.29-1.69). There was also a predilection towards the female gender for both of these polymorphisms. For GSTP1 Ile105Val polymorphism, no significant association was found under any contrast model. In addition, the presence of the double-null genotypes increased the risk of acute myeloid leukemia in both Caucasians and East Asians.

CONCLUSIONS

This meta-analysis suggested that heritable GST status could influence the risk of developing acute myeloid leukemia.

Methylenetetrahydrofolate reductase gene polymorphisms contribute to acute myeloid leukemia and chronic myeloid leukemia susceptibilities: evidence from meta-analyses

PURPOSE

The expression of methylenetetrahydrofolate reductase (MTHFR) is associated with acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). Most studies have linked the common functional C677T and A1298C polymorphisms of the MTHFR gene and susceptibility to AML and CML, but the results were not consistent. The aim of the present study was to derive a more precise estimation of the relationship.

METHODS

Meta-analyses assessing the association of MTHFR C677T and A1298C variations with AML and CML were conducted. Eligible articles were identified from the PubMed and EMBASE databases. All statistical analyses were conducted using Review Manager Software.

RESULTS

10 and 10 studies were included in the meta-analysis about the role of C677T polymorphism on the AML and CML risks, respectively; 6 and 4 studies were included about the role of A1298C polymorphism on the AML and CML risks, respectively. Overall, both the C677T and A1298C polymorphisms were significantly associated with CML risk under the recessive model (P=0.04, OR=1.35, 95% CI=1.02-1.79 for C677T and P=0.003, OR=2.17, 95% CI=1.29-3.63 for A1298C). In addition, the risk of CML was higher in 1298CC genotype carriers than in 1298AA genotype carriers (P=0.004, OR=2.17, 95%=1.28-3.69). Conversely, the overall data failed to indicate a significant association of C677T or A1298C polymorphisms with AML risk under any model.

CONCLUSIONS

The findings provide evidence that C677T and A1298C polymorphisms are risk factors for CML risk.