TP53 Gene Polymorphism in Epithelial Ovarian Carcinoma Patients from North Indian Population and its Pro/Pro Variant is Potentially Contributing to Cancer Susceptibility

Abstract

Background: Ovarian cancer is the leading cause of death from gynecological malignancies. The early stages of this disease are asymptomatic and more than 75% of the cases are diagnosed with regional or distant metastases. P53 is a tumor suppressor gene and is involved in the etiology of ovarian cancer. Studies investigating the associations between the p53 codon 72 polymorphism and ovarian cancer risk showed conflicting results. A polymorphism at codon 72 of the human tumour-suppressor gene, p53, results in translation to either arginine or proline. To investigate the association of p53 codon 72 polymorphism with susceptibility to epithelial ovarian cancer in North Indian women and to correlate them with clinicopathological characteristics of disease. Methods: The study was conducted on 100 epithelial ovarian cancer patients and 100 healthy controls. Genotyping of p53 codon 72 polymorphism was examined by PCR with allele-specific primers. Results: The proportions of individuals homozygous for the arginine allele, homozygous for the proline allele, and heterozygous for the two alleles were 33%, 17%, and 50% among women screened for ovarian cancer; 62%, 6%, and 32% among the control group. A significant correlation was found between the arg/pro (p<0.0004) and pro/ pro (p<0.0006) genotypes with respect to the arg/arg genotype. Pro/pro genotype emerged as the risk factor with an OR of 5.3 and a RR of 2.5. Conclusion: Our study suggests that Pro/Pro genotype of 72 codon polymorphism could be an independent susceptibility marker in northern Indian women with ovarian carcinomas.