***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: We investigated the prognostic significance of genetic polymorphism in glutathione-S transferase mu 1 ( GSTM1 ) , glutathione-S transferase theta 1 ( GSTT1 ) , NAD(P)H : quinone oxidoreductase ( NQO1 ) and myeloperoxidase ( MPO ) , the products of which are associated with drug metabolism as well as with detoxication , in 193 patients with de novo acute myeloid leukemia ( AML ) other than M3 . Of the patients , 64.2 % were either homozygous or heterozygous for GSTT1 ( GSTT1 + ) , while 35.8 % showed homozygous deletions of GSTT1 ( GSTT1− ) . The GSTT1− group had a worse prognosis than the GSTT1 + group ( P = 0.04 ) , whereas other genotypes did not affect the outcome . Multivariate analysis revealed that GSTT1− was an independent prognostic factor for overall survival ( relative risk : 1.53 ; P = 0.026 ) but not for disease-free survival of 140 patients who achieved complete remission ( CR ) . The rate of early death after the initiation of chemotherapy was higher in the GSTT1− group than the GSTT1 + group ( within 45 days after initial chemotherapy , P = 0.073 ; within 120 days , P = 0.028 ) , whereas CR rates and relapse frequencies were similar . The null genotype of GSTT1 might be associated with increased toxicity after chemotherapy The objective of the study was to investigate the effect of genetic polymorphisms in glutathione S-transferases ( GST ) on the survival of acute myeloid leukaemia patients receiving adriamycin induction therapy . A total of 89 patients were included in the study . Patients who carried at least one GSTM1 allele had trend towards a better survival ( mortality rate ratio ( RR ) 0.588 ; 95 % CI 0.334 - 1.036 ) than GSTM1 * 0/0 patients . However , at low accumulated adriamycin dose , GSTM1 * 0/0 cases had a better survival than people expressing the gene ( RR=6.1 ; 95 % CI=1.2 - 11.0 ) . The GSTT1 and GSTP1 genotype did not influence the survival in any of the groups We analyzed prospect ively 1213 adults with de novo acute myeloid leukemia ( AML ) to ascertain the prognostic impact of cytogenetic abnormalities on complete remission ( CR ) rate , 5-year cumulative incidence of relapse ( CIR ) , and 5-year overall survival ( OS ) . All patients received similar induction therapy . Median follow-up for surviving patients was 8.3 years . Nonprioritized cytogenetics distinguished t(8;21 ) and inv(16)/t(16;16 ) as conferring a significantly better prognosis than normal karyotype . Prognostic impact of many abnormalities could not be determined independently because of their association with complex karyotype . Neither complex karyotype nor secondary aberrations affected outcome of patients with t(8;21 ) , inv(16)/t(16;16 ) , or t(9;11 ) . Among other patients , those with complex karyotypes had significantly worse outcomes than cytogenetically normal patients . Based on outcome for specific cytogenetic abnormalities and karyotype complexity , patients were divided into 3 risk groups : favorable ( CR 88 % , CIR 54 % , OS 55 % ) , intermediate ( CR 67 % , CIR 67 % , OS 24 % ) , and adverse ( CR 32 % , CIR 92 % , OS 5 % ) . Multivariate analyses confirmed the major contribution of cytogenetics to the probability of attaining CR , CIR , and OS . For the adverse-risk group , the probability of achieving CR was 4.0 and 11.9 times lower , the probability of relapse 3.0 and 4.4 times higher , and the risk of death 2.1 and 4.3 times higher than those for the intermediate and favorable groups , respectively . We conclude that although the prognostic impact of many recurring abnormalities has not been ascertained independently of complex karyotype , cytogenetics is among the most useful factors predicting attainment of CR , CIR , and long-term survival in adult AML Acute lymphoblastic leukemia ( ALL ) is the most common malignancy in children . It accounts for one fourth of all childhood cancers and approximately 75 % of all childhood leukemias . Some prognostic factors determine the outcome of therapy [ e.g. age , sex , initial white blood cell count ( WBC ) , etc . ] ; however , it is believed that other mechanisms such as glutathione S-transferase ( GST ) gene mutation , the expression of lung resistance protein ( LRP ) , and multidrug resistance-associated protein ( MRP ) also plays a role in treatment failure . In this study , GST gene mutations including GSTM1 and GSTT1 were evaluated in patients with leukemia . Thirty newly diagnosed ALL patients younger than 15 years of age participated in the present study . Bone marrow aspiration and biopsy were evaluated for immune phenotyping and DNA was extracted for GST genotyping . All data plus sex , age , initial WBC count , central nervous system ( CNS ) or testicular involvement , immune phenotype , and outcome ( relapse or not ) were analyzed statistically . Genotyping showed that 46 % were double null , 50 % were M1 null and 93.3 % were T1 null for GST mutations . There was no statistically significant relationship between GSTT1 and GSTM1 mutations , or between double null status , prognostic factors and relapse ( P > .05 ) . So , although the results of GST mutations were consistent , it seems that these mutations are not statistically significant Glutathione S-transferases ( GSTs ) are phase II detoxification enzymes involved in the metabolism of carcinogens and anticancer drugs , known also to interact with kinase complexes during oxidative or chemical stress-induced apoptosis . We were interested whether their polymorphic variants may account for differences in outcome of patients with acute myeloid leukemia ( AML ) following chemotherapy .  We studied the prognostic role of polymorphisms in three GST genes ( GSTP1/M1/T1 ) in a large patient cohort of the German Austrian Acute Myeloid Leukemia Study Group , treated according to prospect i ve multicenter clinical trials ( AML HD98A : 254 patients ; AML HD98-B : 100 patients ) , with a median follow-up of 46 months . Looking at short-term adverse drug reactions , homozygous carriers of the GSTP1 * 105 Val allele had a faster neutrophil and platelet recovery ( P=0.002 and 0.02 , respectively ) and a reduced need of red cell and platelet transfusions ( P=0.01 and 0.03 , respectively ) . Response to induction chemotherapy  did not vary according to GST polymorphisms . Multivariable Cox regression models revealed a significant better relapse-free ( RFS ) and overall survival for the GSTP1 * 105 Val ( P=0.003 and 0.03 , respectively ) , whereas GSTT1 and GSTM1 genotypes had no significant impact . The favorable impact of GSTP1 * 105 Val on RFS seems to be restricted to the subgroup of patients exhibiting a normal karyotype 
    Output:
    
Our study suggested that GSTT1 null genotype and GSTT1/GSTM1 double-null genotype were associated with a worse treatment outcome for AML patients , especially in Asian population