Significance of 8-OHdG Expression as a Predictor of Survival in Colorectal Cancer
Myunghee Kang, Soyeon Jeong, Sungjin Park, Seungyoon Nam, Jun‐Won Chung, Kyoung Oh Kim, Jungsuk An, Jung Ho Kim
Abstract
The incidence of colorectal cancer (CRC) is increasing worldwide. 8-hydroxy-2′-deoxyguanosine (8-OHdG), one of the most prevalent DNA alterations, is known to be upregulated in several carcinomas; however, 8-OHdG has not been used to predict the prognosis of patients with CRC. We aimed to determine 8-OHdG levels in patients with CRC using immunohistochemistry and conducted a survival analysis according to the pathological stage. The 5-year event-free survival (EFS) and disease-specific survival (DSS) hazard ratios (HRs) of the low 8-OHdG subgroup were 1.41 (95% confidence interval (CI): 1.01–1.98, p = 0.04) and 1.60 (95% CI: 1.12–2.28, p = 0.01), respectively. When tumor node metastasis (TNM) staging and 8-OHdG expression were combined, the 5-year EFS and DSS HRs of patients with CRC with low 8-OHdG expression cancer at the same TNM stage (stage Ⅲ/Ⅳ) were 1.51 (95% CI: 1.02–2.22, p = 0.04) and 1.64 (95% CI: 1.09–2.48, p = 0.02), respectively, compared to those with high 8-OHdG expression cancer, indicating a poor prognosis. Therefore, low 8-OHdG expression is a significant predictive factor for 5-year EFS and DSS in patients with CRC, and it can serve as an essential biomarker of CRC.