Significant progress in the field of cancer epigenetics has enhanced the understanding of epigenetic mechanisms in cellular processes and in abnormal events involved in tumorigenesis. Many studies have investigated epigenetic alterations in cancer cells and have revealed that epigenetic deregulation is important for the development of malignancy. These studies have also demonstrated that epigenetic changes are present in almost every human cancer, and that different cancers may harbor a specific 'epigenetic signature', which can be used for cancer control. This review focuses on studies that have revealed the existence of specific epigenetic changes related to particular cancer types and associated risk-factor exposures, and how these epigenetic signatures may be exploited in the diagnosis, treatment and prevention of cancer.