Correlation between XRCC1 Arg399Gln genetic polymorphisms and susceptibility to bladder cancer: a meta-analysis

Genetic Variants Related to Cell Cycle and Stability of Telomere in Patients with Glioma

Background:

Glioma, most common primary malignant brain tumor in adults, is highly aggressive and associated with a poor prognosis. Evaluate the association of polymorphisms related of to the cell cycle, integrity and DNA repair with gliomas, as well as lifestyle habits, comorbidities, survival and response to treatment.

Methods:

Were studied 303 individuals distributed into: Study Group - 100 patients with gliomas, regardless of the degree of malignancy, and Control Group - 203 individuals without clinical signs of the disease. These polymorphisms were genotyped by TaqMan^® SNP Genotyping Assay. Significance level was set at 5%.

Results:

Smoking, alcohol consumption, systemic arterial hypertension (SAH) and diabetes mellitus (DM) prevailed in patients, compared to controls (P=0.0088, P=0.0001, P=0.0001, P=0.0011, respectively). In the logistic regression analysis, alcohol consumption and SAH were identified as independent risk factors for gliomas (P=0.0001, P=0.0027, respectively). Patients with low-grade gliomas showed survival in one year (92.0±6.8%), compared to patients with high-grade gliomas (24.0±5.3; P=0.011).

Conclusion:

Polymorphisms involved in cell cycle, telomere protection and stability and DNA repair are not associated with gliomas. On the other hand, alcohol consumption and SAH stand out as independent risk factors for the disease. Low-grade gliomas, response to treatment and the combination of chemotherapy with Temozolomide and radiation therapy show increased survival of patients.

A 3' untranslated region polymorphism rs2304277 in the DNA repair pathway gene OGG1 is a novel risk modulator for urothelial bladder carcinoma

Altered DNA repair capacity may affect an individual's susceptibility to cancers due to compromised genomic integrity. This study was designed to elucidate the association of selected polymorphisms in DNA repair genes with urothelial bladder carcinoma (UBC). OGG1 rs1052133 and rs2304277, XRCC1 rs1799782 and rs25487, XRCC3 rs861539, XPC rs2228001, and XPD rs13181 were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 200 UBC cases and 200 controls. We found association of OGG1 rs2304277 [odds ratio (OR)_GG = 3.55, 95% confidence interval (CI) = 1.79-7.06] and XPC rs2228001 (OR_AC = 2.38, 95% CI = 1.43-3.94) with UBC. In stratified analysis with respect to smoking status, OGG1 rs2304277 and XPC rs2228001 exhibited increased risk in smokers [(rs2304277 OR_GG = 4.96, 95% CI = 1.51-16.30) (rs2228001 OR_AC = 2.19, 95% CI = 1.02-4.72)] as well as nonsmokers [(rs2304277 OR_GG = 2.95, 95% CI = 1.26-6.90) (rs2228001 OR_AC = 2.57, 95% CI = 1.31-5.04)]. These polymorphisms were also associated with both low-grade [(rs2304277 OR_GG = 3.73, 95% CI = 1.72-8.09) (rs2228001 OR_AC = 2.18, 95% CI = 1.21-3.92)] and high-grade tumors [(rs2304277 OR_GG = 3.45, 95% CI = 1.52-7.80) (rs2228001 OR_AC = 2.81, 95% CI = 1.48-5.33)] as well as with non-muscle-invasive bladder cancer [(rs2304277 OR_GG = 4.03, 95% CI = 1.87-8.67) (rs2228001 OR_AC = 2.14, 95% CI = 1.20-3.81)] and muscle-invasive bladder cancer [(rs2304277 OR_GG = 3.06, 95%CI = 1.31-7.13) (rs2228001 OR_AC = 2.95, 95%CI = 1.51-5.75)]. This is the first study on DNA repair gene polymorphisms and UBC in the Pakistani population. It identifies OGG1 rs2304277 and replicates XPC rs2228001 as significant modulators of UBC susceptibility.