(227j) Fluid Mechanics and Cancer: Breakup of Tumor Cells in Flow

Tumor cells have to travel through blood capillaries to be able to metastasize and make colonies in distant organs. Among the numerous cells that are shed by the primary tumor, very few survive in circulation. In vivo studies have shown that tumor cells can undergo breakup at microcapillary junctions.  Thus, a major factor contributing to the death of these circulating tumor cells is the mechanical damage due to extensional flows in microcirculation. It is currently unclear what hydrodynamic and biomechanical factors contribute to fragmentation and moreover how different are the breakup dynamics of highly and weakly metastatic cells. In this study, we design a microfluidic device for flow-induced breakup of cancer cells. We observe several different modes of breakup of cancer cells, which have striking similarities with microfluidic droplet breakup. We quantify the breakup time and find that highly metastatic prostate cancer cells take longer to breakup than lowly metastatic cells suggesting that circulating tumor cells may dynamically modify their deformability to avoid fragmentation in blood flow. Our study highlights the important role that fluid mechanics plays in cancer.