Fig. 2.

Age related epigenetic alterations inducing susceptibility (AREAS) in the prostate. Specific epigenetic alterations, including loss of imprinting, gene methylation, and histone modifications, are either stable (1) or erode (2) over time in the epithelium (or stroma) of the prostate that does not develop cancer. Alternately, in the prostate gland that develops cancer epigenetic alterations occurring during aging result in gene expression changes that confer a selective advantage to early neoplastic changes (3). These changes represent a field of susceptibility and may be accelerated by environmental insults. These epigenetic changes that occur in aging tissues are frequently selected for in tumors (4). Other cancer specific epigenetic alterations arise within the tumor and are age-independent (5).