Beyond Mice and Men: Alternative Vertebrate and Invertebrate Models in Cancer Biology

While cancer looms large in the public and scientific minds, this can result in a quite narrow view of its range and manifestations. The centering of human clinical investigations and the popularity of mouse models leave many unaware of fascinating findings about cancer in other species. Comparative oncology shows that cancer can be found not just in mammals but widely across the tree of animals, a realization that broadens views of the disease in fundamentally important ways. Examples include protective mechanisms of cancer-resistant species, transmissible cancers, and questions about whether cancer risk is intrinsic to metazoan life. I highlight strong evidence for cancer in invertebrates, focusing on Drosophila, which not only show many hallmarks of cancer but also induce host responses mimicking those of human patients, including antitumor immunity. A wide-ranging study of cancer-bearing species enhances the potential for transformative advances in battling this ancient disease.