Application of evolutionary principles to epidemiological problems indicates that cultural characteristics influence the evolution of parasite virulence by influencing the success of disease transmission from immobilized, infected hosts. This hypothesis is supported by positive correlations between virulence and transmission by biological vectors, water, and institutional attendants. The general evolutionary argument is then applied to the causes and consequences of increased virulence for three diseases: cholera, influenza and AIDS.

Similar to parasites, cancer cells depend on their hosts for sustenance, proliferation and reproduction, exploiting the hosts for energy and resources, and thereby impairing their health and fitness. Because of this lifestyle similarity, it is predicted that cancer cells could, like numerous parasitic organisms, evolve the capacity to manipulate the phenotype of their hosts to increase their own fitness. We claim that the extent of this phenomenon and its therapeutic implications are, however, underappreciated. Here, we review and discuss what can (...) be regarded as cases of host manipulation in the context of cancer development and progression. We elaborate on how acknowledging the applicability of these principles can offer novel therapeutic and preventive strategies. The manipulation of host phenotype by cancer cells is one more reason to adopt a Darwinian approach in cancer research. -/- . (shrink)