Soon my pet mice will have nothing to worry about but stroke and heart disease. Actually, I think cancer has been cured in mice several times over. The problem

Soon my pet mice will have nothing to worry about but stroke and heart disease. Actually, I think cancer has been cured in mice several times over. The problem is that mice have a two to three-year lifespan and several orders of magnitude fewer cells than a human. So cancer in mice is very, very different from cancer in humans. Mice don't even get the kind of cancer that concerns us -- the kind that develops after dozens of years, and that can evade a human's anti-cancer mechanisms (which are more powerful than those in mice, because protecting humans from cancer is a much harder task!)