Evaluation of TP53 codon 72 polymorphism in esophageal cancer susceptibility in Eastern Anatolia Region of Turkey

INTRODUCTION: The tumor suppressor TP53 gene plays a key role in the regulation of cell cycle. Polymorphisms in this gene have been associated with many cancers including esophageal cancer (EC). Many previous studies have focused on the relationship between TP53 codon 72 polymorphism and EC risk in most of the populations except Turkish population. The aim of this study was to explore the effect of codon 72 polymorphism on the EC risk in eastern Turkey.
METHODS: The codon 72 polymorphism was genotyped by real time polymerase chain reaction (qPCR) with TaqMan SNP genotyping assay in 79 patients and 80 healthy control subjects.

RESULTS: No statistically significant difference was observed in distribution of genotype and allele frequencies. Heterozygous Arg/Pro (CG) was the most frequent genotype in both patients and controls. Homozygous Arg/Arg (GG) genotype frequency was higher in patients than controls, but not statistically significant (p>0.05). However, tumor location in the lower part of the esophagus was significantly higher in non-C carriers (GG, Arg/Arg) compared to C-carriers (CG/CC) (p=0.01). G-carriers were also more likely to have poorer survival compared to patients with CC genotype (p=0.04).

DISCUSSION AND CONCLUSION: Our results suggest that the Codon 72 polymorphism was not associated with the EC in eastern Turkey. However, GG genotype (Arg/Arg) may have a role in tumor development at the lower location of the esophagus. Additionally, G carriers may exist the poorer survival compared to the non-G carriers (CC). Therefore, it is thought that individuals with CC genotype (Pro/Pro) may have better survival.