Chronic inflammation or tissue wounding is associated with tumor development. In The EMBO Journal, Antonio et al. use a transparent zebrafish model to show that neutrophils recruited to wound sites are rapidly 'distracted' to nearby pre-neoplastic cells. This interaction promotes the proliferation of these pre-neoplastic cells, a process that involves prostaglandin E2. Morpholinos that retard neutrophil development diminish the wound-associated increase in the population expansion of pre-neoplastic cells, but those that target macrophage development do not. Similar correlations can be seen in human melanoma tumors with tissue ulceration and neutrophil infiltration, both of which are indicators of a poor prognosis. It remains unclear what chemoattractant factors recruit neutrophils to the pre-neoplastic cells and what other roles neutrophils serve that promote tumorigenesis.

EMBO J. (1 July 2015) doi:10.15252/embj.201490147