Oxysterols are oxygenated derivatives of cholesterol formed in the human body or ingested in the diet. By modulating the activity of many proteins, e.g., liver X receptors, oxysterol-binding proteins, or some ATP binding cassette transporters, oxysterols can affect many cellular functions and influence various physiological processes, e.g., cholesterol metabolism, membrane fluidity regulation, intracellular signaling pathways. Therefore, the role of oxysterols is also important in pathological conditions, e.g., atherosclerosis, diabetes mellitus type 2, neurodegenerative disorders. Finally, current evidence suggests that oxysterols play a role in malignancies, such as breast, prostate, colon, and bile duct cancer.
This review summarizes the physiological importance of oxysterols in the human body, with a special emphasis on their roles in various tumors.