ABSTRACT
Background: Transforming growth factor-beta1 [TGF-beta1] has a critical role in breast cancer initiation and progression
Objectives: We have investigated the possible differences in two promoter polymorphisms [-509C/T and -800G/A] of TGF-beta1 gene between breast cancer cases and controls
Patients and Methods: A total of 100 patients with confirmed breast cancer and 100 subjects without breast cancer was selected. Two promoter polymorphisms [-509C/T and -800G/A] of TGF-beta1 gene were genotyped using PCR-based restriction fragment length polymorphism [RFLP] method
Results: The allele frequencies were 63% for C allele and 37% for T allele of SNP -509C/T and 66% for G allele and 34% for A allele of SNP -800G/A. Although no significant difference has observed between two groups, according to the genotype distribution, However, the TT genotype of -509 and AA genotype of -800 was significantly associated with breast cancer risk [odds ratio [OR] = 2.409; 95% confidence interval [CI] = 1.087 - 5.337, P = 0.030; and OR = 2.383; CI = 1.039 - 5.40, P = 0.040, respectively]. In addition, a multinomial logistic regression model shown, homozygous of -800 G/A [OR = 0.570; 95% CI = 0.362 - 0.896, P = 0.015]; and HDL-C [OR = 0.935; 95% CI = 0.906 - 0.965, P < 0.001] were the selected variables associated with the presence of breast cancer. Haplotype analysis has shown no significant association between TGF-beta1 haplotypes and breast cancer risk
Conclusions: Our results indicated that among two promoter polymorphisms of the TGF-beta1gene, -800G/A compared to -509C/T is more associated with breast cancer