The role of TERT-CLPTM1L SNPs, hTERT expression and telomere length in the pathogenesis of oral squamous cell carcinoma

Abstract

The aim of this study was to assess TERT-CLPTM1L single-nucleotide polymorphisms (SNPs) (rs402710 C/T in the CLPTM1L gene; rs2736100 A/C and rs2736098 G/A in the TERT gene) as risk factors for development of oral squamous cell carcinoma (OSCC), and to investigate the relationship between the analyzed polymorphisms, relative telomere length (RTL), telomerase expression and clinicopathologic characteristics of OSCC in a Serbian population. Paraffin-embedded tumor samples and buccal swabs from cancer-free controls were genotyped using PCR-RFLP, while tumor RTL values and telomerase expression were estimated by real-time PCR and immunohistochemistry, respectively. CLPTM1L rs402710 and TERT rs2736100 polymorphisms were associated with a significantly increased risk of OSCC, and TERT rs2736098 with a significantly decreased risk. No significant association was found between TERT-CLPTM1L polymorphisms, tumor RTL values, telomerase expression, and clinicopathologic features, although a trend towards longer telomeres was evident in telomerase-positive samples and less advanced tumors. Kaplan-Meier survival analysis showed that patients with longer telomeres in their tumors had significantly better overall survival than patients with shorter telomeres. Our research seems to provide strong evidence for an association between CLPTMIL rs402710C/T and TERT rs2736100A/C SNPs and the risk of OSSC, and suggests that higher tumor RTL values and positive hTERT expression may be applicable as early prognostic markers.