Role of nitric oxide in cancer biology

The role of nitric oxide (NO) in tumorigenesis is multifactorial. NO can pa rticipate in the complicated process of carcinogenesis by mediating DNA dam age in early phases of tumorigenesis, as well as support tumor progression through the induction of angiogenesis and suppression of the immune respons e. This paper addresses the effects of NO on transcriptional regulation fol lowing DNA damage and cyclooxygenase expression in the multistep process of tumorigenesis.