> Virtually all old mice die of cancer, especially in the lab. If GzmK doesn't mitigate immune system aging, GzmK-null mice are still going to die of cancer, for little or no change in lifespan.

Would introducing the cancer-reducing TP53 genes found in elephants[1][2] to mice help with this? Or would they likely just be too incompatible, with the species difference being too large?

[1] https://news.cancerresearchuk.org/2023/08/12/can-elephants-g...

[2] https://jamanetwork.com/journals/jama/fullarticle/2456041