Alcohol (ethanol) consumption is a risk factor for development as well as progression of many cancers (Seitz and Stickel, 2007, Boffetta and Hashibe, 2006). Chronic alcohol consumption is estimated to be directly responsible for about 4% of all cancers worldwide (Boffetta and Hashibe, 2006). Cancers promoted by alcohol include cancers of the upper aerodigestive tract (oropharynx, larynx, esophagus), liver, breast, colon, and rectum (Boffetta and Hashibe, 2006, Seitz and Stickel, 2007). The mechanisms underlying alcohol promotion of these cancers are not certain. However, several distinct alcohol-induced cancer promoting mechanisms have been postulated. These include alcohol mutagenic effects, changes in retinoic acid, folate, or estrogen metabolism, and oxidative stress (Seitz and Stickel, 2007). But, none has been shown to fully explain the mechanism of alcohol-induced aggressive behavior of cancer cells that ultimately results in metastasis, cancer occurrence, and poor outcome.
