Cancer and aging: more puzzles, more promises?

In this issue of Cell Cycle, a new paper shows that metformin, an oral antidiabetic drug that activates AMP-activated protein kinase, prolongs both mean and maximal life span and prevents reproductive aging of female mice. Unexpectedly, metformin did not decrease the incidence of cancer in this mice strain. Here, we discuss the relationship between aging and cancer, the mechanism of metformin action, and the prospects of using this compound for life span extension in humans.