Reactive Oxygen Species: A link between chronic inflammation and cancer

* Author for correspondence: : Dr. (Mrs) Khushtar A Salman, Department of Biochemistry, J.N Medical College, AMU, Aligarh 202002 (U.P), India. Email: [email protected]. Abstract. Chronic inflammation is associated with an increase reactive oxygen and nitrogen species, giving rise to epigenetic changes, genomic instability and DNA mutations, which thereby contribute to tumour initiation and progression. Regardless of its origin, ‘smouldering’ inflammation in the tumour microenvironment has many tumour-promoting effects. It is a component of the tumour microenvironment and is a recognized hallmark of cancer. It aids in the proliferation and survival of malignant cells, promotes angiogenesis and metastasis, subverts adaptive immune responses, and alters responses to hormones and chemotherapeutic agents. Transcription factors (e.g. Nuclear Factor kappa-B and STAT3) modulate the inflammatory response through soluble mediators (cytokines, chemokines) and cellular components (e.g. tumour-associated macrophages) promoting tumorigenesis. Chronic inflammation contribute to about 1 in 4 of all cancer cases. Thus, cancer-related inflammation represents a target for novel diagnostic and therapeutic strategies.