For example, dynamic changes in the biophysical properties of cancer cells occur during cancer progression, and fluidization predicts tumor aggressiveness in vivo.3 During development, measuring cell flows in the growing zebrafish tailbud4 shows a transition in tissue fluidity that enables a directed posterior flow of composite tissue and is affected by inhibition of Wnt or Fgf signaling or cadherin, two functions. Here, CDH17 is linked to cancer.