Question: What are the most promising ideas you’ve encountered in your cancer research?
Paul Davies: Well there is something that interests me and it does look quite promising, and maybe I’m inflating its importance because I can understand it, but for most of the history of biology the stuff of life well it used to be thought of some sort of magic matter, but then about 100 years ago the cell became seen as a sort of bag of complex chemicals and so the chemical approach to cancer is of course well known, chemotherapy. About 60 years ago the informational side of life became apparent with the discovery of DNA and the genetic code and so on and so now we have genetics and bioinformatics and the whole sort of informational approach, genomics, proteomics and so on that follows from that, so we got two views of cancer cells, bag of chemicals and an information processing system, but there is a third view. A cancer cell is a physical object. It’s got properties like everything else. It’s got viscoelastic properties. It’s got a mass. It’s got a size and a shape and an internal organization and it’s full of pumps and levers and chains and other paraphernalia that engineers and physicists are very familiar with, so it’s a physical system and we would like is to integrate all of these three points of view, but the physical part has been very much neglected, so for example, healthy cells and cancer cells respond very dramatically to things like forces and stresses in their immediate vicinity. The micro-environment in which a cell grows can dramatically affect its gene expression, how it behaves, what it does, and also its physical properties. It can greatly change its elasticity, for example. Cancer cells become usually much softer than healthy cells and they get all bent out of shape and part of the reason we can diagnose cancer is because they become deformed, swollen and funny shapes and funny shaped nuclei and so trying to understand the relationship between the forces that act on these cells, and I’m talking about good old push and pull Newtonian forces, nothing mysterious here and their chemical and genetic response. Trying to map those correlates I think is a really important way forward, so maybe we can control cancer by controlling or manipulating the micro-environment.
You’ve got to get away from the idea cancer is a disease to be cured. It’s not a disease really. It’s, the cancer cell is your own body, your own cells, just misbehaving and going a bit wrong, and you don’t have to cure cancer. You don’t have to get rid of all those cells. Most people have cancer cells swirling around inside them all the time and mostly they don’t do any harm, so what we want to do is prevent the cancer from gaining control. We just want to keep it in check for long enough that people die of something else, to put it crudely, and maybe we can do that by controlling the microenvironment. I should say that tumors, primary tumors very rarely kill people and of course if you have a tumor pressing on a nerve or something it could be problematic, but mostly tumors can be shrunk and they can be kept in check or they can be removed surgically. It’s when the cancer spreads around the body, the metastatic process that things get grim. If we can either prevent that metastatic process or prevent the cells that are circulating around the body making a home in organs where they don’t belong by controlling the physical properties of the tissues that surround them in some way to be worked out, then maybe this is a whole new approach. It’s not… You don’t zap the cancer with chemicals. You don’t bombard them with rays to make them die and you don’t… We’re not talking about gene therapy where you try and insert some sort of gene to switch them off or something. We’re talking about something much simpler, about controlling the physics of the cells and their immediate environment in a way that will change their behavior and their gene expression, so it’s really a whole new way of thinking about it and I’m really hopeful that we’re going to learn a lot of interesting things. I might say that this cancer research I think it’s really important to inform cancer not just from subjects like physics and chemistry, but also from astrobiology.
Astrobiologists have spent a longtime thinking about the nature of life and its evolutionary history, how it began, how it evolved over time. I think they have a lot to contribute to the understanding of cancer, so earlier I was talking about the Holy Grail of astrobiology is to find life 2.0. That is a second form of life right here on Earth. I think cancer is life 1.1. It’s like another form of life. It’s closely related to healthy life. A healthy body is one form of life. Cancer is in a way nature’s experiment with life. It’s life almost as we know it, but modified in a certain way and I think studying cancer it’s not a one way street. Studying cancer could provide huge insights for astrobiologists into the nature of life itself. Cancer biologists really are not, mostly are not very interested in evolution. They’re not evolutionary biologists. They’re cancer biologists or cell biologists, but we really only understand the nature of life itself by looking at that long evolutionary history. Cancer is not something confined to human beings. It’s found in all multi cellular organisms where the adult cells proliferate, so it’s widespread in the biosphere. It’s a phenomenon that is deeply related to the history of life itself, so by studying cancer I think we can illuminate the history of life itself and vice versa, so my thinking in running this cancer forum is to just get expertise from as many fields as we can, bring it to bear, hopefully some very well defined problems in cancer biology and really try and nail them and try and move the subject along.
Recorded April 15, 2010
Interviewed by Austin Allen
It seems to me that our communication will begin in terms of mathematics and physics.