Earlier quoted context omitted.
The cancers you're thinking of in Tasmanian Devils are the result of a transmissible (!) tumor. The cancerous cells aren't the result of mutations within the animal's body, but instead are introduced into it from another infected animal. As such, genetic therapies are unlikely to have an effect.
As such, genetic therapies are unlikely to have an effect. Can you back that up somehow? That doesn't sound at all right to me. Edit: For the upvote, downvote brigade -- with zero reply so far, but this comment has gone to zero and back to one umpteen times already -- I'm genuinely curious. This isn't some kind of gotcha question. I have a genetic disorder. I have umpteen relatives who have had cancer. I actually hav…
They're less like normal cancers, and more like parasites made of cancerous cells. Moreover, they're not even typical cancer cells -- they're cancer cells which have been dividing (and continuing to mutate) since the disease first came into existence, to the extent that their genetic material has become wildly divergent from that of the host species.
Typical genetic therapies for cancer focus on the hope that enough of the normal apoptotic pathways still exist that the cancer cells can be "convinced" to recognize themselves as cancerous and undergo cell death. In the case of transmissible tumors, though, it's likely that these pathways have been entirely destroyed through selective pressures on the cancer.