UMLS:C0026986 - FACTA Search

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Query: UMLS:C0026986 (myelodysplastic syndrome)
14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myelodysplastic syndrome (MDS) is a hematological disorder that occurs primarily in the elderly as an acquired, sporadic disease. Familial cases of MDS are rare. We have identified a kindred with three affected individuals, with early age of onset, suggesting a possible inherited predisposition to this disease. Using a molecular genetic approach, we examined whether bands 5q31 or 7q22 or both, the chromosomal regions most frequently associated with sporadic MDS, are involved in familial expression of MDS in this pedigree. Linkage analysis using polymorphic microsatellite DNA markers demonstrated that neither 5q31 nor 7q22 cosegregated with MDS in this family. There was no history of common environmental or occupational exposure among family members with MDS. In addition, analysis of polymorphisms at two loci [glutathione S-transferase T1 and M1 (GSTT1 and GSTM1)] involved in carcinogen detoxification and associated with cancer susceptibility, including increased risk for MDS, showed no evidence for enhanced sensitivity to environmental carcinogens in affected family members. Taken together, our findings suggest that (1) there is an inherited predisposition to MDS in this kindred; and (2) genes at 5q31 and 7q22, the regions most commonly associated with sporadic MDS, are excluded from a causal role in this family's disease.
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PMID:Genetic analysis of familial myelodysplastic syndrome: absence of linkage to chromosomes 5q31 and 7q22. 972 26

Glutathione S-transferases (GSTs) M1 and T1 are known to be polymorphic in humans. Both polymorphisms are due to gene deletions, which are responsible for the existence of null genotypes. The gene defect of GSTT1 has been reported to be associated with an increased risk of myelodysplastic syndromes, astrocytoma and meningioma. A lack of GSTM1 was associated with tobacco smoke-induced lung and bladder cancer. In this study we examined whether the GSTT1 and/or GSTM1 homozygous null genotypes were associated with an increased risk of ovarian cancer using a multiplex polymerase chain reaction protocol. The GSTT1 null genotype was observed in 14% of the control subjects that had never suffered from neoplastic disease (n = 115) and in 16% of the patients affected with ovarian cancer (n = 103, OR 0.87, 95% CI 0.39-1.92, P = 0.73). A lack of GSTM1 was observed in 38% of the control subjects and in 46% of the patients (OR 0.77, 95% CI 0.44-1.32). This difference was not significant (P = 0.34). Similarly, no significant differences were obtained if GSTT1 and/or GSTM1 null genotypes were analyzed in subgroups of control subjects and ovarian cancer patients between the ages of 20-40, 41-70 and 71-90 years and in individuals with a positive family history of neoplastic disease. GSTT1 and/or GSTM1 null genotypes were not significantly associated with the histologic type and grade or FIGO (International Federation of Gynecology and Obstetrics) stages of the ovarian carcinomas. In conclusion, GSTT1 and/or GSTM1 null genotypes are not markers for an increased risk of ovarian cancer.
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PMID:Glutathione S-transferase T1 and M1 gene defects in ovarian carcinoma. 975 Dec 55

It has become clear that several polymorphisms of human drug-metabolizing enzymes influence an individual's susceptibility for chemical carcinogenesis. This review gives an overview on relevant polymorphisms of four families of drug-metabolizing enzymes. Rapid acetylators (with respect to N-acetyltransferase NAT2) were shown to have an increased risk of colon cancer, but a decreased risk of bladder cancer. In addition an association between a NAT1 variant allele (NAT*10, due to mutations in the polyadenylation site causing approximately two fold higher activity) and colorectal cancer among NAT2 rapid acetylators was observed, suggesting a possible interaction between NAT1 and NAT2. Glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) are polymorphic due to large deletions in the structural gene. Meta-analysis of 12 case-control studies demonstrated a significant association between the homozygous deletion of GSTM1 (GSTM1-0) and lung cancer (odds ratio: 1.41; 95% CI: 1.23-1.61). Combination of GSTM1-0 with two allelic variants of cytochrome P4501A1 (CYP1A1), CYP1A1 m2/m2 and CYP1A1 Val/Val further increases the risk for lung cancer. Indirect mechanisms by which deletion of GSTM1 increases risk for lung cancer may include GSTM1-0 associated decreased expression of GST M3 and increased activity of CYP1A1 and 1A2. Combination of GST M1-0 and NAT2 slow acetylation was associated with markedly increased risk for lung cancer (odds ratio: 7.8; 95% CI: 1.4-78.7). In addition GSTM1-0 is clearly associated with bladder cancer and possibly also with colorectal, hepatocellular, gastric, esophageal (interaction with CYP1A1), head and neck as well as cutaneous cancer. In individuals with the GSTT1-0 genotype more chromosomal aberrations and sister chromatid exchanges (SCEs) were observed after exposure to 1,3-butadiene or various haloalkanes or haloalkenes. Evidence for an association between GSTT1-0 and myelodysplastic syndrome and acute lymphoblastic leukemia has been presented. A polymorphic site of GSTP1 (valine to isoleucine at codon 104) decreases activity to several carcinogenic diol epoxides and was associated with testicular, bladder and lung cancer. Microsomal expoxide hydrolase (mEH) is polymorphic due to amino acid variation at residues 113 and 139. Polymorphic variants of mEH were associated with hepatocellular cancer (His-113 allele), ovarian cancer (Tyr-113 allele) and chronic obstructive pulmonary disease (His-113 allele). Three human sulfotransferases (STs) are regulated by genetic polymorphisms (hDHEAST, hM-PST, TS PST). Since a large number of environmental mutagens are activated by STs an association with human cancer risk might be expected.
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PMID:Polymorphisms of N-acetyltransferases, glutathione S-transferases, microsomal epoxide hydrolase and sulfotransferases: influence on cancer susceptibility. 1002 93

Glutathione S-transferase (GST) M1 polymorphism is a marker for susceptibility to smoking-related neoplasms, such as lung and bladder cancer. Recently, a genetic deletion of GSTT1, an isoenzyme of GST, has been reported to be associated with myelodysplastic syndromes (MDS). A 59-year-old man with a long-term smoking habit was treated successfully for non-small-cell lung cancer. Four years after the surgical removal of his lung cancer, he developed MDS and died. Using a polymerase chain reaction-based genotyping method, he was found to have a deletion of both the GSTM1 and GSTT1 genes. Screening for the deletion of the GSTM1 and GSTT1 genes may be useful for assessing individual genetic susceptibility to smoking-related lung cancer and MDS.
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PMID:A patient with genetic deletion of glutathione-S-transferase T1 and M1 who developed non-small-cell lung cancer and myelodysplastic syndromes. 1061 69

Epipodophyllotoxin-associated secondary myeloid leukemia is a devastating complication of acute lymphoblastic leukemia (ALL) therapy. The risk factors for treatment-related myeloid leukemia remain incompletely defined. Genetic deficiencies in glutathione S-transferase (GST) activities have been linked to higher frequencies of a number of human malignancies. Our objective was to determine whether the null genotype for GSTM1, GSTT1, or both, was more frequent in children with ALL who developed treatment-related myeloid malignancies as compared to those who did not. A PCR technique was used to assay for the null genotype for GSTM1 and GSTT1 in 302 children with ALL, 57 of whom also subsequently developed treatment-related acute myeloid leukemia or myelodysplastic syndrome. Among children with ALL who did not develop treatment-related myeloid malignancies, the frequencies of GSTM1 and GSTT1 wild-type, GSTM1 null-GSTT1 wild-type, GSTM1 wild-type-GSTT1 null, and GSTM1 and GSTT1 null genotypes were 40%, 42%, 9% and 9%, respectively. The corresponding frequencies for patients who developed acute myeloid malignancies were 42%, 32%, 11% and 16%, respectively (P = 0.26). A statistically significant increase in the frequency of the GST null genotype was observed in male patients who developed myeloid malignancies as compared to male ALL control patients (P = 0.036), but was not observed in female patients (P = 0.51). Moreover, a logistic regression analysis of possible predictors for myeloid malignancies, controlling for gender and race, did not reveal an association of GSTM1 or GSTT1 null genotypes (P = 0.62 and 0.11, respectively) with treatment-related malignancies. Our data suggest that GSTM1 and GSTT1 null genotypes may not predispose to epipodophyllotoxin-associated myeloid malignancies.
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PMID:Glutathione S-transferase genotypes in children who develop treatment-related acute myeloid malignancies. 1067 38

GSTM1 and GSTT1 are polymorphic genes. Absence of enzyme activity is due to homozygous inherited deletion of the gene, reducing detoxification of carcinogens such as epoxides and alkylating agents and potentially increasing cancer risk. We hypothesized that GST null genotype would increase risk of acute myeloid leukemia and myelodysplasia (AML/MDS) in children. DNA was extracted from bone marrow slides of 292 AML/MDS patients. PCR amplification was used to assign GSTM1 and GSTT1 genotypes for cases and controls. Given that the frequency of the null genotype varies by ethnicity and that the majority of the cases were Caucasian, analyses were restricted to 232 white (non-Hispanic) cases and 153 Caucasian non cancer controls. The frequency of GSTM1 null was significantly increased in AML/MDS cases compared with controls [64 versus 47%; odds ratio (OR), 2.0 [95% confidence interval (CI), 1.3-3.1]; P = 0.001], whereas the frequency of GSTT1 null genotype in AML/MDS cases was not statistically different from controls. AML comprises biologically distinct subtypes, and a test for homogeneity revealed a statistically significant difference among subtypes (P = 0.04; df, 8) for GSTM1 only. In particular, there was an increased frequency of GSTM1 null genotypes in French-American-British groups M3 [82%; n = 22; OR, 5.1 (95% CI, 1.6-21.3)] and M4 [72%; n = 53; OR, 2.9 (95% CI, 1.4-6.0)]. We conclude that the GSTM1 null genotype is a significant risk factor for childhood AML, particularly French-American-British groups M3 and M4. This may indicate an important role for exogenous carcinogens in the etiology of childhood AML.
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PMID:Glutathione S-transferase polymorphisms in children with myeloid leukemia: a Children's Cancer Group study. 1086 89

The most serious long-term complications of anti-tumor therapy are secondary malignancies. Parameters which might allow an estimation of the individual risk to develop a therapy-induced neoplasia are urgently needed. We examined whether the genotypes of the glutathione S-transferases (GST) M1 and T1, which metabolize various cytostatic drugs, as well as reactive oxygen species, influence the risk for secondary neoplasia. In a retrospective study, we analyzed peripheral blood lymphocyte or bone marrow DNA samples from 213 patients with acute myeloid leukemia (AML) and 128 with myelodysplastic syndromes (MDS) 44 of whom suffered from therapy-associated AML/MDS. The control group consisted of 239 healthy individuals with comparable composition as to race and sex. GSTM1 and GSTT1 were analyzed by multiplex PCR. Comparison between patients and control group revealed a significant (P=0.0003) overrepresentation of combined deletions of both GSTM1 and GSTT1 (double null genotype) in the group of patients with AML/MDS secondary to chemo- and/or radiotherapy of a carcinoma of the breast. In this group, 55% of the patients displayed the double null genotype as compared with 8.8% in the control group. We conclude that patients with carcinoma of the breast and inheritance of a combined gene deletion of GSTM1 and GSTT1 might bear an increased risk to develop a secondary therapy-induced hematologic neoplasia. An insufficient detoxification of cytostatic drugs such as cyclophosphamide is suggested to represent the underlying pathomechanism.
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PMID:Increased risk for therapy-associated hematologic malignancies in patients with carcinoma of the breast and combined homozygous gene deletions of glutathione transferases M1 and T1. 1179 13

Hydroquinone is a myelotoxin that is found in many foods and is also formed through the metabolism of benzene. Human exposure to benzene is associated with the development of myelodysplastic syndrome and acute myelogenous leukemia. Hydroquinone is genotoxic in several in vitro and in vivo test systems, inducing micronuclei (MN), sister-chromatid exchange (SCE), and chromosomal aberrations. Glutathione S-transferases (GSTs) are a superfamily of polymorphic enzymes involved in the conjugation of reactive chemical intermediates to soluble forms. These enzymes play a key role in the detoxification of endogenous and exogenous compounds, and the polymorphic genes GSTM1, GSTT1, and GSTP1 have been associated with the differential metabolism of several genotoxicants. In the present study, we have evaluated the effect of GSTM1, GSTT1, and GSTP1 polymorphisms on the frequency of MN and SCE induced by hydroquinone in human lymphocytes. Lymphocytes were obtained from 15 healthy non-smoking donors, and their GSTM1, GSTT1, and GSTP1 genotypes determined. Treatment of cultures of the lymphocytes with hydroquinone significantly increased the overall frequencies of MN and SCE (P<0.0001). Individuals with the GSTM1 null genotype had a significantly higher frequency of MN compared with GSTM1-present individuals (P=0.013); in contrast, the GSTM1 genotype had no effect on hydroquinone-induced SCE frequency. The other polymorphisms did not significantly affect the frequencies of MN or SCE. These results suggest that GSTM1 is involved in the metabolic fate of hydroquinone and that polymorphisms in GSTM1 could be related to inter-individual differences in DNA damage arising from the exposure to this compound.
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PMID:GSTM1, GSTT1, and GSTP1 genotypes and the genotoxicity of hydroquinone in human lymphocytes. 1514 65

Glutathione S-transferases (GSTs) are a group of enzymes involved in the detoxification process of carcinogens and other substances. The genes encoding isoenzymes M1 and T1 have "null" alleles, which are polymorphic in humans. Our purpose was to examine whether the GSTM1 and GSTT1 homozygous null genotypes have an impact on the response to recombinant human erythropoietin (rhuEpo) treatment in MDS patients. We analyzed lymphocyte DNA samples from 27 patients with all types of myelodysplastic syndromes (MDS) at the time of diagnosis. All patients were scheduled to receive rHuEpo in doses of 150 u/Kg/day for a period of 12 weeks in order to obtain and maintain stable responses. A multiplex polymerase chain reaction (PCR) was used to genotype both GSTM1 and GSTT1 simultaneously, in responders and non-responders to rhuEpo with respect to various pretreatment parameters: haemoglobin, white blood cell count, platelets, serum erythropoietin, transfusion requirements and bone marrow blasts. The data obtained were evaluated by chi2 test and odds ratio were extracted. Twelve out of 27 evaluated patients demonstrated an erythroid response (44%). Nine out of the 12 patients (75%) responding after 12 weeks of treatment had GSTM1 null genotype (OR=3.4). In contrast, only 1 responder (8.3%) was homozygotes of GSTT1 null genotype. Furthermore, no statistically significant difference in the response rate of the different MDS subgroups was observed. Our results suggest that a treatment with rHuEpo may be effective in achieving a stable erythroid response in MDS patients who carry an homozygous deletion of the GSTM1 gene.
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PMID:Treatment of MDS patients with recombinant human erythropoietin and the role of GSTs. 1559 30

GSTM1, GSTT1 and GSTP1 Ile105Val that are members of the GST gene family encode for Phase II drug/xenobiotic metabolizing enzymes, primarily with detoxifying function, and are polymorphic in humans. GSTM1 and GSTT1 homozygous deletion genotypes do not express the enzymes. It has been hypothesised that individuals with homozygous deletion of the GSTM1 and/or GSTT1 gene may have lower detoxification capacity towards genotoxic agents therefore those individuals may be at increased risk of myelodysplastic syndrome which is a preleukemic condition. Genetic polymorphism of GSTM1, GSTT1 and GSTP1 Ile105Val was investigated in a case-control study in a Hungarian patient population comprising 86 patients with myelodysplastic syndrome and 99 hospital-based controls. There were no statistically significant differences between cases and controls for the GSTM1, GSTT1 and GSTP1 Ile105Val genotype frequencies for any of the three genes separately and in various combinations. This suggests that these genetic polymorphisms may not be strong risk factors, if any, for myelodysplastic syndrome.
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PMID:Glutathione S-transferase enzyme polymorphisms in a Hungarian myelodysplasia study population. 1849 76

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