Aubrey de Grey has proposed comprehensively preventing cancer by eliminating genes that code for lengthening of telomeres altogether and supplementing with stem cells on a periodic basis. The periodic stem cell infusions would also act as a delivery mechanism for his proposed solution to the mitochondria problem, i.e. moving certain critical mitochondrial genes to the nucleus.

I think aging will take too long to cure for most of us to benefit from it, so I generally emphasize cryonics. But it is certainly fascinating to read de Grey's proposals, and seems plausible enough that it could work soon if there is big money behind it, i.e. to be a good gamble. It has a high payout in total human lives saved, since (assuming rapid global distribution) developing it a day sooner would effectively save 100,000 people; thus even if one does not anticipate being alive to benefit, that is a significant charitable accomplishment.

Arguably the same is the case of suspended animation research -- it could easily be that reversible cryopreservation would happen within our lifetimes if there was big money behind it. The beauty of suspended animation research is that it coincides with increasing the chances of cryonics working. Rejuvenation research is likely more applicable to the eventual reanimation phase of cryonics.