title: Hemodynamic shear stress stimulates migration and extravasation of tumor cells by elevating cellular oxidative level.
abstract: Cancer cells are shed into the blood stream and are exposed to hemodynamic shear stress during metastasis. It has been shown that shear stress can destroy circulating tumor cells (CTCs) both in vitro and in vivo. However, it remains unclear whether shear stress can modulate the properties and functions of tumor cells in a manner that might help CTCs to exit circulation. In this study, we established a microfluidic circulatory system to apply physiological fluid shear stress on breast cancer cells and demonstrated that an arterial level of shear stress significantly enhanced tumor cell migration in transwell and wound healing assays, and enhanced extravasation in a transendothelial assay. Circulatory treatment elevated the intracellular levels of reactive oxygen species (ROS), which is an early and indispensable event for activating the extracellular signal-regulated kinases (ERK1/2). Subsequently, ERK1/2 activation promoted the migration of tumor cells and enhanced their extravasation. Finally, reducing cellular ROS production suppressed tumor cell extravasation in both a transendothelial assay and a zebrafish model. This new understanding of how fluid shear stress promotes tumor cell migration has important implications in cancer treatment and can help us to identify potential therapeutic targets for inhibiting tumor progression.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
authors.forename: Shijun
authors.initials: S
authors.lastname: Ma
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
authors.forename: Afu
authors.initials: A
authors.lastname: Fu
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
authors.forename: Geraldine Giap Ying
authors.initials: GG
authors.lastname: Chiew
authors.affiliation: Faculty of Health Sciences, University of Macau, Taipa, Macau, China. Electronic address: kluo@umac.mo.
authors.forename: Kathy Qian
authors.initials: KQ
authors.lastname: Luo
mesh_terms: D002465:Cell Movement; D006439:Hemodynamics / Q000235:genetics*; D006801:Humans; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013314:Stress, Mechanical
chemical_list: D017382:Reactive Oxygen Species
keywords: Cell migration; Circulating tumor cells; ERK1/2; Extravasation; Reactive oxygen species; Shear stress