In an earlier poster paper (1) we proposed that cancer can be viewed not only as a fatal disease but also as a local aberrant, rejuvenation, in an organism, and this fact can be useful for developing new anti-aging and anti-cancer treatments. In this paper we provide additional evidence from human and experimental animal studies in support of this view. First, we discuss cancer genes as candidate targets for anti-aging interventions. We review examples in which the life of experimental animals has been prolonged in situations of increased activity of proto-oncogenes - or decreased activity of tumor suppressors - in normal (non-cancerous) cells in vivo. Studies of genetic polymorphisms revealed similar effects on longevity in humans. Second, we discuss the possibility of treating cancer with embryonic stem cells. The fact that cancer cells do not, age, means that these cells overcome aging host cells. However, cancer cells can be suppressed by young and quickly proliferating non-cancer cells, such as embryonic stem cells. The grafting of these cells in the tumor environment could be a prospective non-toxic anti-cancer treatment. We discuss recent evidence in support of this view.