From what I understand, one form of cancer is a faulty gene responsible for the programmed death of a cell.
Not long ago, popular wisdom used to say neurons don't regenerate. However that is no longer believed to be true, if I am to believe what the internet says. For me, this begs the question: can neurogenesis result in faulty death genes which in turn result in overgrowth of the number of neurons? Would those neurons be functional? And if so, if theoretically such a brain could be artificially sustained without a body, would its growth be beneficial (in terms of intelligence)?