Biogeneticist Eric S. Lander makes the connection:
Therapeutic development has already been transformed by genomics. There are 800 different anticancer drugs in clinical development today. Cancer drugs used to be just cellular poisons, but almost all of these new ones are targeted at particular gene products that have been discovered. But it’s just a start. Some of the new cancer drugs can miraculously make tumors disappear. The problem is that, a year later, the cancer in many cases comes roaring back, because some of the cells have developed mutations that make them resistant. So genome scientists are now finding and targeting these mutations as well. Remember in the 1980s, when HIV was a fatal disease? What made it become a chronic, treatable disease? It was a combination of three drugs. Any one of those drugs alone, the virus could mutate its way around. But with the combination of all three, the chance that a virus could find its way around all of them was vanishingly small.
That’s what’s going to be happening in cancer. If you didn’t know the HIV story, you would be depressed: you put all this work into the drug, and a year later the cancer has developed resistance. But if you understand that this is a game of probability, and there is only a finite number of cancer cells and each has only a certain chance of mutating, and if we can put together two or three independent attacks on the cancer cell, we win.