Meriban Karadoğan, Fatma Turkan Polat, Veysel Gok, Derya Koçer, Veysel Uzen
Oxidative stress contributes to carcinogenesis through deoxyribonucleic acid (DNA) damage, and 8-hydroxy-2-deoxyguanosine (8-OHdG) is a well-established biomarker of oxidative DNA injury. This study aimed to evaluate oxidative stress in pediatric acute lymphoblastic leukemia (ALL) by measuring serum 8-OHdG levels before and after chemotherapy. This retrospective case-control study included 32 children diagnosed with ALL and 30 age- and sex-matched healthy controls. Serum 8-OHdG levels were measured using an enzyme-linked immunosorbent assay prior to treatment and after the initiation of maintenance therapy, approximately one month following intensive chemotherapy. Comparisons between groups were performed using the Mann-Whitney U test, and within-patient changes were assessed using the Wilcoxon signed-rank test. Pretreatment serum 8-OHdG levels were significantly higher in children with ALL compared with controls (P < .001), indicating increased oxidative DNA damage. Serum 8-OHdG levels significantly decreased after chemotherapy in children with ALL (P < .001). However, no statistically significant difference was observed between post-treatment 8-OHdG levels and those of the control group (P = 1.0). No significant associations were found between pretreatment 8-OHdG levels and white blood cell count or body mass index. Children with ALL exhibit significantly elevated serum 8-OHdG levels, supporting a role for oxidative stress in disease pathogenesis. The reduction in 8-OHdG levels following chemotherapy suggests a potential relationship between treatment response and oxidative DNA damage, indicating that 8-OHdG may serve as a useful biomarker in pediatric ALL.