Complex Interplay between Oxidative Stress and Inflammatory signaling in Development of Neurodegenerative Diseases and Cancer

Abstract Introduction Oxidative stress (OS) and inflammation are closely related with cancer progression and neurodegenerative diseases. Excess ROS generated either oxidize biomolecules or triggers the signaling cascade thereby activating inflammation. The activation of inflammation causes immune cells to secrete cytokines and chemokines which recruits various immune cells to the site of infection or oxidative stress. This interrelation between oxidative stress and inflammation in cancer and neurodegenerative diseases is discussed in the article. Methods The role of oxidative stress and inflammation in cancer progression and neurodegenerative disease related literature were collected to obtain data. A narrative review was constructed after obtaining all the relevant information to provide a detailed note on it. Results In cancer, OS and inflammation aids in various oncogenic metabolic events including proliferation, differentiation, angiogenesis, migration, invasion, metabolic changes and evading programmed cell death. The disproportion between reactive oxygen species (ROS) and antioxidants in the body is termed as OS which damages the macromolecules (nucleic acids, lipids and proteins). It leads to dysfunction in biological signaling cascade. Prolonged oxidative stress triggers inflammation by stimulating transcription factors (NF-κB, p53, HIF-1α, PPAR-γ, Nrf2, AP-1) which altered expression of various other genes and proteins such as growth factors, tumor suppressor genes, oncogenes, pro-inflammatory cytokines etc., triggering cancer cells survival. In neurodegenerative diseases, both OS and inflammation activates astrocytes and microglia, which in turn altered energy metabolism, proteostasis and redox signaling in brain by activating various protein kinases. Conclusion The present review article delineates the complex interplay between OS and inflammation in some cancers (Colorectal, breast and lung cancer) and neurodegenerative diseases (Alzheimer’s and Parkinson’s disease).