title: Tumor necrosis factor alpha and beta and interferon gamma gene polymorphisms in Turkish breast cancer patients.
abstract: Cytokine genes are important for researching cancer predisposition to cancers that elicit anti-tumor immune response. In this study, we investigated the association between breast cancer and tumor necrosis factor alpha (TNF-α) -308 (G>A), TNF-β +252 (A>G), and interferon gamma (IFN-γ) +874 (T>A) gene polymorphisms in a Turkish population. This study involved 204 female breast cancer patients and 204 healthy female controls. Genomic DNA was extracted from EDTA-preserved peripheral venous blood of patients and controls by a salting-out method and analyzed by polymerase chain reaction, allele-specific oligonucleotide polymerase chain reaction, and restriction fragment length polymorphism. TNF-α -308 genotype was found to have no effect on breast cancer susceptibility. However, there were statistically significant differences between the genotype frequencies of patients and controls for TNF-β polymorphism (p = 0.016) and the allele and genotype frequencies for the IFN-γ polymorphism (p = 0.0312 and p = 0.001, respectively). In the composite genotype analysis, the TNF-α/β GAAG composite genotype (p = 0.0424), the TNF-α/IFN-γ GGTT and GATT composite genotypes (p = 0.0296 and p = 0.0129, respectively), the TNF-β/IFN-γ AGTT composite genotype (p = 0.0003), and the TNF-α/β/IFN-γ GGAGTT and GAAGTT composite genotypes (p = 0.0437 and p = 0.0038, respectively) were estimated to have a protective effect against breast cancer. However, the TNF-α/IFN-γ GGTA composite genotype is a risk factor for breast cancer (p = 0.0156). In conclusion, TNF-β +252GG genotype was found more frequent in Turkish breast cancer patients than controls and IFN-γ TA+AA genotypes were estimated to increase breast cancer risk significantly in Turkish population.
authors.affiliation: Department of Medical Biology and Genetics, Ondokuz Mayis University, Samsun, Turkey. nevinbalci@hotmail.com
authors.forename: Nevin
authors.initials: N
authors.lastname: Karakus
authors.forename: Nurten
authors.initials: N
authors.lastname: Kara
authors.forename: Ali Naki
authors.initials: AN
authors.lastname: Ulusoy
authors.forename: Cihangir
authors.initials: C
authors.lastname: Ozaslan
authors.forename: Yüksel
authors.initials: Y
authors.lastname: Bek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001943:Breast Neoplasms / Q000235:genetics*; D016022:Case-Control Studies; D016207:Cytokines / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics*; D008233:Lymphotoxin-alpha / Q000235:genetics*; D008875:Middle Aged; D016017:Odds Ratio; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D012307:Risk Factors; D017422:Sequence Analysis, DNA; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*; D014421:Turkey
chemical_list: D016207:Cytokines; D008233:Lymphotoxin-alpha; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma