The zebrafish as a model for cancer.

For the last three decades significant parts of national science budgets, and international and private funding worldwide, have been dedicated to cancer research. This has resulted in a number of important scientific findings. Studies in tissue culture have multiplied our knowledge of cancer cell pathophysiology, mechanisms of transformation and strategies of survival of cancer cells, revealing therapeutically exploitable differences to normal cells. Rodent animal models have provided important insights on the developmental biology of cancer cells and on host responses to the transformed cells. However, the rate of death from some malignancies is still high, and the incidence of cancer is increasing in the western hemisphere. Alternative animal models are needed, where cancer cell biology, developmental biology and treatment can be studied in an integrated way. The zebrafish offers a number of features, such as its rapid development, tractable genetics, suitability for in vivo imaging and chemical screening, that make it an attractive model to cancer researchers. This Primer will provide a synopsis of the different cancer models generated by the zebrafish community to date. It will discuss the use of these models to further our understanding of the mechanisms of cancer development, and to promote drug discovery. The article was inspired by a workshop on the topic held in July 2009 in Spoleto, Italy, where a number of new zebrafish cancer models were presented. The overarching goal of the article is aimed at raising the awareness of basic researchers, as well as clinicians, to the versatility of this emerging alternative animal model of cancer.