Human lifespan is limited by aging of both mitotic and post-mitotic cells. These two forms of aging may occur by distinct or overlapping mechanisms. Telomere erosion has been shown to limit the proliferative lifespan of human somatic cells. Other vertebrates, such as mice, possess robust telomerase activity in most cell types and their somatic cells display finite replicative lifespans as a con...

Cancer Control 321 determine the inherent risk they presented. Over 10,000 specimens were divided into three groups: nonproliferative lesions,proliferative lesions without atypia, and proliferative lesions with atypia. Their findings suggested a 1.9 times greater risk for proliferative lesions without atypia and 5.3 times greater risk for proliferative lesions with atypia.1,2 Subsequent case-co...