The Effect of Thiol-Disulfide Homeostasis on Prognosis in Patients with Early-Stage Non-Small Cell Lung Cancer

Objective: Lung cancer has a poor prognosis. Thiol groups with high antioxidant capacity are converted to disulfide bonds through biochemical reactions that neutralize different oxidant compounds. The thiol-disulfide (SH-SS) homeostasis has significant effects on cell mechanisms, transcription, and apoptosis. Here we present the prognostic role of dynamic SH-SS homeostasis in patients operated for NSCLC. Materials and Methods: Patients operating for early-stage NSCLC were prospectively analyzed. SH-SS homeostasis tests were measured using the automated spectrophotometric method. Results: This study enrolled 138 subjects, including 77 patients and 61 healthy controls. Native thiol and total thiol levels were significantly lower in the patient group. The disulfide-to-native thiol ratio, which is an indicator of oxidative stress in SH-SS homeostasis, also reached a level of statistical significance in the patient group (p<0.001). According to the cut-off values (305 and 326.3), the median overall survival rate was significantly shorter in patients with low native thiol and total thiol levels (p<0.001). Conclusions: This study demonstrated decreased native thiol and total thiol levels as well as decreased disulfide levels and SS/SH ratio in early-stage NSCLC. Impaired SH-SS homeostasis may contribute to lung cancer pathogenesis and poor prognosis because of enhanced oxidative stress.