Free radicals and antioxidants in normal versus cancerous cells — An overview

Abstract

Oxygen is vital for aerobic processes of metabolism and respiration- It has been also implicated in many diseases and degenerative conditions. Free radicals formed from reactive oxygen and nitrogen species act as key players in the initiation and progression of tumor cells and enhance their metastatic potential. The imbalance in the formation and use of free radicals in the tissue creates oxidative stress. Inadequacy in normal cells antioxidant defense system or excessive free radical formation or even both can cause the cell to experience the oxidative stress. This review outlines the involvement of free radicals in different aspects of cancer, from prevention to initiation, progression, treatment and to reduce morbidity and mortality.