Interstitial flows promote amoeboid over mesenchymal motility of breast cancer cells revealed by a three dimensional microfluidic model

Abstract

Malignant tumors are often associated with an elevated fluid pressure due to the abnormal growth of vascular vessels, and thus an increased interstitial flow out of the tumor. Recent in vitro work revealed that interstitial flows critically regulated tumor cell migration within a three dimensional biomatrix, and breast cancer cell migration behavior depended sensitively on the cell seeding density, chemokine availability and flow rates. In this paper, we focus on roles of interstitial flows in modulating heterogeneity of cancer cell motility phenotype within a three dimensional biomatrix. Using a newly developed microfluidic model, we show that breast cancer cells (MDA-MB-231) embedded in a 3D type I collagen matrix exhibit both an amoeboid and a mesenchymal motility, and interstitial flows promote the cell population towards the amoeboid motility phenotype. Furthermore, the addition of exogenous adhesion molecules (fibronectin) within the extracellular matrix (type I collagen) partially rescues the mesenchymal phenotype in the presence of the flow. Quantitative analysis of cell tracks and cell shape shows distinct differential migration characteristics of amoeboid and mesenchymal cells. Notably, the fastest moving cells belong to the subpopulation of amoeboid cells. Together, these findings highlight the important roles of biophysical forces in modulating tumor cell migration heterogeneity and plasticity, as well as the suitability of microfluidic models in interrogating tumor cell dynamics at single-cell and subpopulation level.

Interstitial fluid pressure regulates collective invasion in engineered human breast tumorsviaSnail, vimentin, and E-cadherin

“…Our system provides insights into the results of single-cell suspension culture models and illuminates how IFP affects collective cell behavior. 13–15, 19 …”

Microfluidic modeling of the biophysical microenvironment in tumor cell invasion

“…A critical component for modeling interstitial flow through 3D ECM in a microfluidic platform is to confine natively derived or synthetic ECM within an area where fluid flow can be applied through the ECM in a controlled way. To create a microfluidic platform for tumor cell invasion in the presence of interstitial flow, a number of labs have developed unique microfabrication methods to pattern type I collagen in a three parallel channel configuration 65, 115–118 . The common feature of all the devices is to develop micro-patterned structures to confine biomatrices in designated places.…”

“…B). To overcome this limitation, our lab confined cell-embedded collagen using a contact line pinning method 117, 118 . In our work, parallel PDMS microridges (or contact lines) with a cross section of 10 μm by 5 μm were fabricated to confine collagen within a wall-less channel.…”

“…Work in our lab demonstrated that interstitial flow at flow speed of 2 μm/s promotes amoeboid over mesenchymal motility of breast cancer cell invasion by carrying away adhesion molecules such as fibronectin. Cells lacking adhesion contacts prefer to migrate via amoeboid motility 118 . These studies revealed critical information on how interstitial flow influences tumor cell invasion at the single cell level and the dynamic interaction of tumor cells with their environment.…”

“…Images in B are reproduced from reference 116 with permission from the Royal Society of Chemistry. Images in C are reproduced from references 65, 115 with permission from the Proceedings of the National Academy of Sciences, and images in D are reproduced from reference 118 with permission from the Royal Society of Chemistry.…”