Estrogens receptors and oxidative damage in the liver.

There is considerable evidence that reactive oxygen species (ROS) have a causative role in chronic hepatic injury and cancer development via direct and indirect mechanisms. Estrogens produce free oxygen radicals through redox cycling and affect cell proliferation, also in the liver. We are presently involved in evaluating the possible relationship between estrogens receptor expression, type of receptor, oxidative DNA damage and c-myc in chronic liver disease. The data on DNA adducts, c-myc mRNA and variant estrogen receptor in patients with HCV- or HBV-related chronic liver disease are suggesting that those positive for variant liver estrogen receptor present higher genomic oxidative damage, as reflected in 8-OHdG levels. We are also observing that patients with chronic hepatitis and cirrhosis, when positive for variant estrogen receptor, present higher c-myc m-RNA expression, a factor reportedly associated with increased genomic instability, augmented cytoproliferation and carcinogenesis. Our own and other author's data are shedding new light on estrogen pathophysiology, liver damage and hepatic cancer. Copyright 2002 Elsevier Science Ireland Ltd.