Determinants of oxidative stress and DNA damage (8-OhdG) in squamous cell carcinoma of head and neck.

ABSTRACT

Background: Squamous cell carcinoma of head and neck (SCCHN) is a major concern of health risk in developing countries, such as India. Apart from genetic configuration, environmental and lifestyle factors, as well as poor oral hygiene, provide free radical-generating environment, which may contribute to the development of cancer through DNA damage. Materials and Methods: Here we ascertained the various oxidative stress determinants in diagnosed SCCHN patients with health risk addictions. This study further evaluated the incremental effects inflicted by these lifestyle factors on redox status. The study included 100 consenting SCCHN patients and 90 matched healthy controls. Salivary total antioxidant capacity (TAC), glutathione (GSH), free radicals such as reactive nitrogen species (RNS) and reactive oxygen species (ROS) along with oxidative DNA adduct (8-OHdG) were monitored. Results: Our findings indicated altered salivary oxidant-antioxidant status in SCCHN. A substantial rise in ROS (~2.0 folds) and RNS (~1.4 folds), together with significant lowering in TAC (~1.2 folds) and GSH (~1.7 folds) was observed. The 8-OHdG levels were also found to be considerably higher (P < 0.001) in salivary cell's DNA of these patients. Conclusions: Our results demonstrate significant redox imbalance in cancer patients suggesting their paramount importance in the development of SCCHN.