Live imaging in zebrafish reveals neu(trophil) insight into the metastatic niche.

Non-cancerous immune cells can significantly contribute to tumour progression and metastases. Neutrophils associated with tumours can both promote and inhibit tumour progression, but less is known about how non-associated immune cells contribute to cancer biology. In a recent issue of the Journal of Pathology, He and colleagues use non-invasive, high-resolution imaging of the whole living animal to provide a compelling glimpse at how physiological migration of neutrophils can prepare a metastatic niche and how their activities can be altered by the unintended consequences of targeted therapeutics.