Cancer

A cancerous cell, going about its metastasising ways...

Cancer. Even saying the word can make you gulp. Its one of the great killers, and for decades we've seen a desperate search for a cure. Treatment has always been a type of warfare - cut it out, blast it with chemicals and radiation. Cancer has fascinated me for years now, because it struck me that the assumptions we take into understanding anything, or more generally how we frame our understandings, is pivotal to how far we go with this understanding.

So the assumption we've normally used with cancer is that it's like some foreign agent in our bodies, that needs to be found and killed. That assumption has spread into everyday usage in other areas too, we talk about corruption as a 'cancer' in our society, for example. Unfortunately the chemicals and radiation which are our weapons of choice tend to kill healthy cells in our bodies too, and lots of people who get this treatment end up dying as a result of it, not from the original cancer. Of course oncology has become very sophisticated in how it uses the chemicals and radiation, but the basic assumption is still there.

Of course this is right in some ways, cancer will certainly kill you if left unchecked. But oncology is another one of those things working after the horse has already bolted, a last-ditch emergency action. But there is something absolutely remarkable going on in biology that may have finally cracked what cancer is, and how to prevent it, and treat it if it's already arrived. And it completely ditches the kill-the-fucker framework. I'll get to that in the next post, in this one I want to quickly set out how cancer has been understood up until now, and the problems with these understandings.

There are 3 common models of how cancer works.

1) The multi-step progression model. Some cells mutate randomly into a cancerous type, which is then selected (in the evolutionary sense) over time so that this mutant cell type becomes dominant and you get a tumour made up of these cells, which grows, breaks free and travels to other parts of the body, where this all starts again (metastasis). So the obsession doctors have with whether cancer has 'spread' - metastasis is this spread. Death often follows quickly after metastasis has got well underway.

2) The intrinsic metastasis model. Here the original cell that mutates to become cancerous is thought to contain the inherent potential to metastasise i.e. there is no need for an evolutionary selection process to turn individual mutated cells into a tumour and then into metastasised feral runaways.

3) The metastatic dissemination model. It has been discovered that tumour cells, in breast cancer for example, are found in various sites around the body before the primary tumour is even evident, remaining dormant until later and then often growing and metastasisng in parallel with the cells at the primary site. So metastasis in other words isn't about one tumour spreading around the body, the spread is already there.

All of these models require, to put the most polite spin on it, heroic assumptions to be true. For number 1, what could the possible selective evolutionary pressure be that would encourage cells to mutate and spread around the body causing havoc? Not much survival of the fittest happening there. For number 2, why would some cells have this mutation and then sit idle at different sites around the body for years, even decades, as happens with cancer patients, before growing tumours at these other sites? And for 3, again why would these cells sit idle at various sites around the body without developing tumours, sometimes for years?

What's missing in all of the traditional models is the pretty basic recognition that cells live in a full environment, and that they in no way act separately to this environment. The reductionist tendency of a lot of modern science looks for some single, usually sub-microscopic, 'cause' for things. So the passionate search for genetic causes for diseases, for example, as if genes were the magic ingredient which determines everything else. It's here the work of Donald Ingber from Harvard may be some of the most important scientific work anywhere on the planet.

Donald Ingber. Scientific revolutionary.

For years Ingber, with his work on tensegrity (which I talked about here), has shown that cells behave and change according to the physical forces that they're subjected to. This includes changes to genes as well. So all of the reductionist passion we've had in trying to find THE cause for biological things like cancer in genes has been putitng the cart before the horse. Genes respond to the physical forces we subject our bodies too. So yes you might find that genes do weird things in cancer, but it's quite another thing to say that it's these changes in genes that are causing the cancer.

More on that in the next post.