Combined GSTT1 Null, GSTM1 Null and XPD Lys/Lys Genetic Polymorphisms and Their Association with Increased Risk of Chronic Myeloid Leukemia

Research Progress of B-Cell Lymphoma/Leukemia-2 Inhibitor Combined with Azacytidine in the Targeted Therapy of Acute Myeloid Leukemia

Objective

To investigate the efficacy and safety of azacytidine and B-cell lymphoma/leukemia-2 inhibitors in the treatment of patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS).

Methods

The clinical data of 31 patients with AML/MDS who were clearly diagnosed with AML/MDS were analyzed from 2018.10 to 2021.02, and the total amount of azacyclonol and B-cell lymphoma/leukemia-2 inhibitor was used for single or combined chemotherapy, with a total amount of 75 mg/m2 ∗7 d, divided into 7-10 days of continuous subcutaneous injection, every 28-30 days for a course of treatment. Overall response rate (ORR), median survival, poor response, and genetic mutations were observed.

Results

A total of 104 courses of treatment were completed in 31 patients, the median course was 3 (1-12), and 6 patients who did not complete 2 courses of treatment were not counted in the statistics. After 2 courses, ORR was 72.0%, CRES was 2 (8.0%), mCR was 16 (64.0%), disease stable was 5 (20.0%), treatment failures were 2 (8.0%), mortality was 40.0%, and median survival time was >5 months. Single-agent and combined ORR was 64.3% and 81.8%, respectively, with median survival of 7.25 and 9 months; ORR for MDS and AML was 66.7% and 76.9%, respectively, median survival of 8 and 11 months was 66.7% and 80.0% of ORRs at 260 and V60 years, respectively, and median survival of 7 and 11.5 months; MDS-EB-1. The ORR of MDS-EB-2 was 75.0% and 62.5%, respectively, with median survival times of 11.5 and 6.5 months. During 2 courses and 4 courses, the rate of transfusion dependence was 64.0% and 55.5%, respectively. Fifteen cases were detected by second-generation sequencing, and the results were 14 cases of combined gene mutations.

Conclusion

Azacytidine and B-cell lymphoma/leukemia-2 inhibitors have good efficacy and high safety in the treatment of AML and MDS, and the combined treatment is better than that of monotherapy, but the side effects of combination therapy are large.

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.

Increased Risk of Acute Lymphoblastic Leukemia in Adult Patients with GSTM1 Null Genetic Polymorphism

Purpose

Glutathione S-transferases (GSTT1 and GSTM1) detoxify various endogenous and exogenous compounds and provide cytoprotective role against reactive species. This study aimed to assess the frequency of GSTT1, and GSTM1 polymorphisms in newly diagnosed Sudanese adult patients with acute lymphoblastic leukemia (ALL) and to evaluate the association of these polymorphisms with age, gender and type of ALL.

Patients and Methods

This case–control study included 128 adult Sudanese, untreated newly diagnosed patients with ALL, aged 18 to 74 years and 128 age-gender matched healthy controls. Deletional polymorphisms of GSTT1 and GSTM1 genes were genotyped through a multiplex polymerase chain reaction (PCR) assay using β-globin gene as an internal positive control.

Results

The genotypic frequency of GSTT1 null polymorphism was 22.7% in cases and 14.8% in controls (OR = 1.68, P = 0.111). Statistically significant differences were noted in the frequencies of GSTM1 null polymorphism in cases and controls (OR = 3.7, P = <0.001). Combined GSTT1 null and GSTM1 null gene polymorphisms showed statistically significant difference in patients with ALL as compared to controls (OR = 6.5, CI 95% = 1.42–29.74, P < 0.001).

Conclusion

Irrespective of age at diagnosis, gender, and phenotype of ALL, GSTM1 null polymorphism either alone or in combination with GSTT1 null polymorphism poses significantly increased risk of developing ALL in adults.