Tumour Necrosis Factor Alpha and Oxidative Stress in the Breath Condensate of Those with Non-Small Cell Lung Cancer

Abstract

Background and Aims: Lung cancer is a leading cause of cancer mortality worldwide and is associated with the release of tumour necrosis factor-α (TNF-α), subsequent cellular apoptosis and the generation of oxidative stress. Exhaled breath condensate (EBC) analysis is a non-invasive method for sampling biofluids from the lower respiratory tract. This study aimed to evaluate possible biomarkers of lung cancer by measuring the levels of TNF-α and the oxidation of ascorbic acid in EBC. Patients with lung cancer were enrolled into the study prior to treatment, during treatment and post-treatment, and results compared with an age-matched control population. Material and Methods: Patients with Stage II-IV non small cell lung cancer (NSCLC) were recruited prior to and at stages of their treatment. EBC levels of TNF-α, and rate of ascorbic acid oxidation were measured. Results: A total of 19 patients with NSCLC (mean age 71.37 ± 7.77 yrs) and 25 age-matched control subjects were enrolled. Levels of EBC TNF-α were elevated in the EBC of patients with lung cancer compared with control subjects (1.02 ± 0.07 pg/ml vs. 0.51 ± 0.06 pg/ml, p < 0.0001). Moreover, the rate of ascorbic acid oxidation was significantly greater in the EBC of patients with lung cancer compared with control subjects (2.20% [0.4 – 11.0] vs. 1.00% [0.1 – 8.5], p = 0.0244). Conclusion: TNF-α and the rate of ascorbic acid oxidation was elevated in the EBC of patients with lung cancer regardless of treatment. Longitudinal studies in a larger population are required to evaluate these markers for the effect of treatment and prognosis.