Glutathione S transferase T1 gene polymorphism and its promoter methylation are associated with breast cancer susceptibility in Egyptian women

Abstract

Background Breast cancer (BC) is one of the leading causes of cancer mortality in women. Glutathione S‐transferase (GSTT1) is involved in activation of detoxification reactions and catalysis of chemicals conjugation with glutathione. GSTT1 genotype is a limiting factor for some environmental diseases. Epigenetic changes have an essential role in BC through inappropriate interaction between genomic and environmental risk factors. Aim This study was directed to explore the association of BC risk with GSTT1 genetic variations and its methylation status in Egyptian women. Design and Methods This study included 100 healthy women as the control group and 100 patients were clinically and histologically diagnosed with breast cancer. All blood samples were used for genomic DNA extraction. GSTT1 genotyping was accomplished by multiplex PCR and methylation‐specific PCR was used to analyze the GSTT1 promoter methylation status. Results Breast cancer patients showed significant incidence of null GSTT1 in relation to controls (p = 0.004). GSTT1 gene promoter methylation status showed significant difference between hypermethylated and unmethylated patients when compared with healthy subjects (p = 0.005). GSTT1 promoter methylation status was not significantly associated with null genotype. There was no significant association between GSTT1‐null genotypes and BC stage in cases with or without family history, but for promotor methylation, there was significant association with stage III and IV breast cancer disease. Conclusion GSTT1 null genetic variant and promoter hypermethylation in the GSTT region of the gene may be considered as critical risk factors for BC in Egyptian women.

Addition of Butyric Acid and Lauric Acid Glycerides in Nursery Pig Feed to Replace Conventional Growth Promoters

“…The body has enzymatic and non-enzymatic antioxidant defense systems to combat excess free radicals. GST is a metabolic enzyme crucial to the organism's detoxification [29]. In addition, it participates in the synthesis of steroids; in cases of oxidative stress, its levels are often reduced [30].…”