Association of the Promoter Methylation and the rs12917 Polymorphism of MGMT with Formation of DNA Bulky Adducts and the Risk of Lung Cancer in Mexican Mestizo Population

The relationship between defects in DNA repair genes and autoinflammatory diseases

Tissue inflammation and damage with the abnormal and overactivation of innate immune system results with the development of a hereditary disease group of autoinflammatory diseases. Multiple numbers of DNA damage develop with the continuous exposure to endogenous and exogenous genotoxic effects, and these damages are repaired through the DNA damage response governed by the genes involved in the DNA repair mechanisms, and proteins of these genes. Studies showed that DNA damage might trigger the innate immune response through nuclear DNA accumulation in the cytoplasm, and through chronic DNA damage response which signals itself and/or by micronucleus. The aim of the present review is to identify the effect of mutation that occurred in DNA repair genes on development of DNA damage response and autoinflammatory diseases.

Genetic and epigenetic modifications of adiponectin gene: Potential association with breast cancer risk

BACKGROUND

Adipokines produced by adipose tissue are directly linked to obesity and may contribute to the pathogenesis of cancer. We hypothesized that genetic and epigenetic modifications in the adiponectin (ADIPOQ) gene and their impact on serum ADIPOQ levels may participate in increasing breast cancer (BC) risk. The present study aimed to investigate ADIPOQ +45 T/G gene polymorphism, methylation status at CpG sites -74 nucleotides (nt) and -283 nt of the ADIPOQ gene, and ADIPOQ serum levels in BC obese women.

METHODS

Serum ADIPOQ was measured by an enzyme-linked immunosorbent assay. ADIPOQ +45 T/G gene polymorphism and ADIPOQ promoter methylation status were determined using a polymerase chain reaction (PCR) and a methylation-specific PCR, respectively, in 120 obese women with BC and 120 age-matched controls.

RESULTS

ADIPOQ +45 GG genotype carriers had a significant increased risk of developing BC (odds ratio = 6.2, 95% confidence interval = 1.3-29.6, p = 0.02). ADIPOQ gene methylation at site -74 nt resulted in a 1.7-fold increased BC risk. Methylation at site -283 nt resulted in a 1.9-fold increased BC risk. Moreover serum levels of ADIPOQ were significantly decreased in BC patients and down-regulated in the presence of methylation in both examined sites. By contrast, no association between ADIPOQ gene polymorphism and serum ADIPOQ level was detected. Using both methylated sites in one panel detected cancer breast with 76.67% sensitivity and 62.18% accuracy.

CONCLUSIONS

ADIPOQ +45 T/G polymorphism and ADIPOQ promoter methylation were found to be associated with BC risk in obese Egyptian women.