Live forever? Both cancer cells and stem cells can make a claim to immortality. Left unchecked, tumors will grow indefinitely. And stem cells offer the promise of non-stop rejuvenation.
We´ll find out whether the surprising discovery of stem cells in the brain really can keep our thinking organ young. And we´ll hear the remarkable story of Henrietta Lacks, the woman who unwittingly donated tissue to science in 1951, and whose cancer cells are still grown in laboratories around the world today.