DNA repair gene excision repair cross complementing-group 1 (ERCC1) in head and neck squamous cell carcinoma: Analysis of methylation and polymorphism (G19007A), protein expression and association with epidemiological and clinicopathological factors

摘要

Aims: To evaluate the associations of excision repair cross complementing-group 1 (ERCC1) (DNA repair protein) (G19007A) polymorphism, methylation and immunohistochemical expression with epidemiological and clinicopathological factors and with overall survival in head and neck squamous cell carcinoma (HNSCC) patients. Methods and results: The study group comprised 84 patients with HNSCC who underwent surgery and adjuvant radiotherapy without chemotherapy. Bivariate and multivariate analyses were used. The allele A genotype variant was observed in 79.8% of the samples, GG in 20.2%, GA in 28.6% and AA in 51.2%. Individuals aged more than 45years had a higher prevalence of the allelic A variant and a high (83.3%) immunohistochemical expression of ERCC1 protein [odds ratio (OR)=4.86, 95% confidence interval (CI): 1.2-19.7, P=0.027], which was also high in patients with advanced stage (OR=5.04, 95% CI: 1.07-23.7, P=0.041). Methylated status was found in 51.2% of the samples, and was higher in patients who did not present distant metastasis (OR=6.67, 95% CI: 1.40-33.33, P=0.019) and in patients with advanced stage (OR=5.04, 95% CI: 1.07-23.7, P=0.041). At 2 and 5years, overall survival was 55% and 36%, respectively (median=30months). Conclusion: Our findings may reflect a high rate of DNA repair due to frequent tissue injury during the lifetime of these individuals, and also more advanced disease presentation in this population with worse prognosis.