Abstract 4727: Prognostic roles of DDB2 and XPC mRNA expressions in treatment responses and overall survivals of head and neck cancer patients

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Background: DNA repair genes function in the maintenance of genome integrity and prevent tumorigenesis. On another hand, DNA repair genes modulate cancer cell responses to DNA-damaging therapeutics. We hypothesize that altered expression of DNA repair genes are correlated with therapeutic outcomes of head and neck cancer patients. Patients and methods: Messenger RNA (mRNA) expressions of DDB2 and XPC were examined in specimens of 95 head and neck cancer patients using real-time quantitative RT-PCR. Patients were dichotomized by ROC curve analysis based on their DDB2 and XPC mRNA levels. Overall survival (OS) rates were measured using Kaplan-Meier estimates and the log-rank tests. The adjusted hazard rate ratios (HRRs) were computed by multivariate Cox regressions. Results: The levels of DDB2 and XPC mRNA expression in tumor tissues were reduced (tumor/normal 0.24) and XPC (> 0.36) mRNA levels had improved 5-yr OS rates if they received CCRT (64.4% vs. 41.8% and 73.3% vs. 39.2%). Conclusion: mRNA expressions of XPC and DDB2 might be useful biomarkers for prognosis and efficacy of CCRT medication in head and neck cancer patients. Citation Format: Chang-Shen Lin, Ka-Wo Lee, Jau-Ling Huang, Yu-Chu Wang, Yi-Shan Tsai. Prognostic roles of DDB2 and XPC mRNA expressions in treatment responses and overall survivals of head and neck cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4727. doi:10.1158/1538-7445.AM2014-4727