Longevity Mutations and Cancer
Nature summarizes recent research into longevity mutations and cancer in nematode worms; the results suggest that further investigation of insulin pathway mutations in mammals could prove profitable. "Mutations in the [nematode] C. elegans insulin-receptor gene daf-2 extend lifespan by more than twofold. By contrast, mutations in the gld-1 tumour-suppressor gene cause germ cells to re-enter mitosis, overproliferate and give rise to tumours that kill the animal. When the authors combined the two mutations, however, the lifespan was indistinguishable from that of the daf-2 single mutant - the tumorigenic effect of gld-1 was completely abolished. How might the lack of insulin signalling prevent tumour development? The authors found that cell division decreased and apoptosis increased in the germ lines of the [daf-2 plus gld-1] double mutant compared with the gld-1 single mutant. Interestingly, daf-2 mutations affected only germline mitosis in the tumour, and not in the normal germ lines of otherwise wild-type individuals." Tantalizing hints that there might be a way around the "cancer or aging, pick one" situation.
Link: http://www.nature.com/nrg/journal/v7/n10/full/nrg1972.html