TP53 (RS1042522) POLYMORPHISM IN BREAST CANCER

Objectives: TP53 gene is one of the most important tumour suppressor gene that mainly plays a role in DNA repair, cell apoptosis, cell senescence and cell cycle control. TP53 rs1042522 (Arg72Pro) polymorphism is nonsynonymous polymorphism that alters P53 protein capacity during tumour suppression. Based on the data above, the purpose of this study is to investigate association between TP53 rs1042522 polymorphism and breast cancer risk in hospital-based Turkish women population. Methods: After DNA isolation from peripheral blood of 508 breast cancer patients and 367 healthy women the genotyping for TP53 rs1042522 polymorphism in both groups was done by a PCR-RFLP method. Statistical analysis was done by the χ2 test with 95% confidence intervals and the Hardy-Weinberg equilibrium was confirmed for tested patient and control populations. Results: Genotype frequencies were 48.6%, 46.3% for GG, 40.7%, 44.7% for GC and 10.6%, 9.0% for CC in breast cancer and controls, respectively. There was not statistical difference between genotypes in cases and controls (χ2=1.591, P= 0.451). Allele frequencies for G allele were 69.0% in cases and 69.0% in controls, for C allele 31.0% in cases and 31.0 % in controls. Also, this results were found to be not statistically significant for G and C alleles (G allele: p=0.424, C allele: p=0.501). The distribution of TP53 rs1042522 genotypes was in agreement with HWE for controls (p>0.05). Conclusion: There is no statistically significant association between rs1042522 and the risk of breast cancer in studied hospital-based Turkish women population. For further, rs1042522 polymorphism may be associated with other genetic factors due to the interaction of p53 with various proteins that play role in programmed cell death. Also, the combined effect of TP53 polymorphisms and the genes such as cyclins, cyclin-dependent kinases and p21 which are related with cell cycle control can be studied or clinicopathological characteristics of breast cancer patients might be evaluated in terms of p53 rs1042522 genotypes in larger population size.