Role of survivin gene promoter polymorphism (-31G>C) in susceptibility and survival of esophageal cancer in northern India.

Abstract

Survivin is an upregulated inhibitor of apoptosis protein in esophageal cancer (EC), and a promoter region polymorphism (-31G>C) in the survivin gene has been reported as a modulator of gene expression. We aim to explore the role of survivin -31G>C polymorphism in susceptibility and survival of EC patients in northern Indian population. A case-control study was performed in 500 subjects (250 EC patients and 250 controls), and genotyping was done by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method. Survivin CC genotype was found to be significantly associated with EC susceptibility [odds ratio (OR) = 2.29; 95% confidence interval (CI) = 1.27-4.14; P = 0.006], particularly in males (OR = 4.91; 95% CI = 2.19-11.02; P = 0.0001) having squamous cell carcinoma (SCC) histopathology (OR = 2.4; 95% CI = 1.36-4.21; P = 0.002) at middle third esophagus location (OR = 2.60; 95% CI = 1.40-4.82; P = 0.002). Patients carrying CC genotype were found to have higher susceptibility to lymph node metastasis (OR = 2.82; 95% CI = 1.46-5.48; P = 0.002). However, on survival analysis, no prognostic role of survivin -31G>C polymorphism was detected. In case-only analysis, no gene-environment interaction was observed. Survivin promoter region polymorphism (-31G>C) is associated with susceptibility and clinical characteristics but not prognosis of esophageal cancer in northern Indian population.