Cancer Evolution

A thought-provoking article yesterday from Science Daily. It's called "Are Cancers Newly Evolved Species?" and describes work by a cell biologist who says that we are looking at cancer in the wrong way. Cancer, he says, does not develop from problems with an individual's chromosomal variations, but goes beyond that, so that cancer cells actually evolve into different species. In other words, cancer cells are no longer human cells, but something other than human, because their DNA changes so much. It's a very different take on how scientists view cancer right now.

I have mixed feelings about this proposed theory of cancer.

In some ways, the science seems possible. Cancer cells do mutate and change in ways that are obviously problematic, in terms of figuring out how to deal with them. A new view of how cancer develops could be necessary to determining how to fight it.

On the other hand, I'm not crazy about the "bacteria" metaphor. It seems a step backwards in some ways. We used to view cancer as something outside of ourselves, something to be attacked -- like bacteria. We now view cancer as a "perfect version of ourselves" (as Siddartha Mukherjee puts it in Emperor of All Maladies): our own cells that have figured out a way to keep from dying.

The implications are important. If we view cancer as coming from ourselves, we figure out ways to fight it that are very different than if we think of cancer as an outsider.

So I'm all for a fresh perspective on cancer, but also concerned that the perspective not pull us away from the progress we're making. Certainly this evolutionary theory is a whole lot more complex than older theories about cancer being caused by a virus or something like that. It will be interesting to see how the community reacts to it.