We initially first studied cancer as a disease of structure and function, taking into account that cancer is more than just the sum of the individual mutations within a cancer cell. It is also a disease of altered cell morphology and function. As we preformed these studies, we realized that cancer as a whole could be better understood as a complex adaptive system. A complex adaptive system has three characteristics. The first is that the system consists of a number of heterogeneous agents (cancer cells) that are changing over time. The second characteristic is that the agents (cancer cells) interact with one another. That interaction leads to the third—something that scientists call emergence: In a very real way, the whole becomes greater than the sum of the parts. The key issue is that you can’t really understand the whole system by simply looking at its individual parts. As we studied cancer as as a complex adaptive system, we realized that we had to understand the context of why the cancer system was evolving over time. Cancer evolves over times as a result of intrinsic genetic instability as well as the selection forces applied to it but the tumor microenvironment. The field of Ecology encompassed why cancer as a “new species” arises as well as evolves over time. We believe thinking about cancer in terms of ecological / evolutionary principles will lead to new insights into how to treat and cure cancer.
