Targeting cancer cells is hard. One of the functions of the immune system is to clear out pre-cancerous disease and error state. Cancer proliferates because it evolves in situ to evade immune regulatory checks.
One of the reasons stem cell technology is moving so slowly is that, apart from mammalian cell culture being hard, we're extremely anxious about messing with the growth pathways. Tripping up the gene expression is what causes cancer in the first place. We're trying to find exploits in the same machinery to induce novel transformations without kicking the cell into unregulated growth. It's going to be a long time before I let something like that into my body.
You make a bunch of solid points, IMHO, but to your last sentence - If I’m facing dying due to a neurodegenerative disease, I’d be willing to roll the dice on the possibility of cancer. Facing death seems like a powerful disinhibitiory driver to me....
