Cancer Foraging Ecology: Diet Choice, Patch Use, and Habitat Selection of Cancer Cells

Purpose of Review Here we connect theories of diet choice, patch use, and habitat selection with cancer biology. Key and only partially answered questions include: Do cancer cells' uptake of nutrients conform to theory? What are the supply and total mass of resources within tumors? Can cancer cell foraging strategies provide indicators for tumor dynamics and therapies? We advocate for a new research subdiscipline of cancer foraging ecology. Recent Findings Foraging ecology studies feeding behaviors of organisms as adaptations. Virtually all of life exhibits adaptations relating to diet, patch use, and habitat selection. Cancer cells likely exhibit selective nutrient uptake (diet), local depletion of resources (patch use), and motility (habitat selection). In fact, the evolution of adaptive feeding strategies by cancer cells may be an additional hallmark of cancer. In aggregate, the feeding behaviors of cancer cells can be devastating-acidosis, hypoxia, cachexia, necrosis, tissue invasion, and metastasis. While these are well known, little is known regarding the nutrient uptake strategies of individual cancer cells. Foraging theory provides a strong theoretical basis for anticipating what cancer cells might do and how research on cancer foraging ecology-with impact on metastasis research and therapeutic intervention-should proceed. Summary Normal cells, as "servants" to the whole organism, should not conform to the principles of optimal foraging theory. Cancer cells in response to fluctuating resource supplies, nutrient limitations, and hazards should evolve resource acquisition strategies that are more optimal-foraging-like. Two areas of research make cancer foraging ecology a particularly propitious emerging field. From behavioral and evolutionary ecology, there is a well-developed body of theory suggesting how organisms, including cancer cells, should forage. From cancer cell metabolomics there is a large body of knowledge regarding how cancer cells process and utilize different nutrients as fuel, material, buffers and messenger molecules. We suggest the time is ripe for conjoining foraging ecology with cancer cell metabolomics.