Dynamically stiffening hydrogels differentially modulates malignant transformation of mammary epithelial cells

Abstract

Event Abstract Back to Event Dynamically stiffening hydrogels differentially modulates malignant transformation of mammary epithelial cells Matthew G. Ondeck1, Laurent Fattet2, 3, Spencer Wei2, 3, Jing Yang2, 3 and Adam J. Engler1, 4, 5 1 UC San Diego, Material Science, United States 2 UC San Diego, Moores Cancer Center, United States 3 UC San Diego, Pharmacology, United States 4 UC San Diego, Bioengineering, United States 5 Sanford Consortium for Regenerative Medicine, United States Mammary epithelial cells, e.g. MCF10A, are known to respond to differences in ECM stiffness and undergo epithelial-mesenchymal transition (EMT) on stiffer ECM lacking. While this is akin to the stiff mammary tumors that a woman can detect with manual palpation, breast cancer fibrosis is a dynamic process that results in matrix stiffening from soft (150 Pascal; Pa) to stiff (3000 Pa) over months to years as a result of enhanced collagen expression and lysyloxidase crosslinking. To more accurately mimic the onset of tumor-associated fibrosis, MCF10A mammary epithelial cells were cultured on top of dynamic methacrylated-hyaluronic acid (MeHA) hydrogels, whose stiffness that can be modulated by a two-step polymerization process, and within a matrigel layer. To more appropriately mimic temporal stiffening that occurs in vivo, the photopolymerization step is repeated using a short UV exposure to create stiffen the matrix after MCF10A cells have formed acini; short exposure creates negligible DNA damage or other negative effects on MCF10A cells. Acini remain polarized until the matrix is stiffened at which point some appear to undergo EMT based on morphological assessment. However, the degree of matrix stiffening and culture time prior to stiffening plays a large role in acini transformation; delayed onset of matrix stiffening from 6 to 10 days prevented malignant transformation in 35% of acini while acini were not responsive to stiffening below 1000 Pa. To ensure that early stiffening was not density dependent, acini of differing cell density were transplanted onto stiffening MeHA hydrogels where we found that transformation was independent of acinus size and cell density. Moreover EMT was not cell intrinsic as sequential rounds of stiffening did not permanently induce a specific phenotype, e.g. stiffness-induced EMT cells could revert to acinar cells and vice versa. Of those cells that lost polarity during dynamic stiffening, a subset maintained epithelial markers and failed to show nuclear localized Twist1, an EMT marker, which together suggest that stiffness exhibits transient epigenetic regulation on mammary epithelial cell state during malignant transformation. Keywords: Biomimetic, cell phenotype, 3D scaffold, mechanical property Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: New Frontier Oral Topic: Biomaterials for mechanical interfaces Citation: Ondeck MG, Fattet L, Wei S, Yang J and Engler AJ (2016). Dynamically stiffening hydrogels differentially modulates malignant transformation of mammary epithelial cells. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.00438 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Matthew G Ondeck Laurent Fattet Spencer Wei Jing Yang Adam J Engler Google Matthew G Ondeck Laurent Fattet Spencer Wei Jing Yang Adam J Engler Google Scholar Matthew G Ondeck Laurent Fattet Spencer Wei Jing Yang Adam J Engler PubMed Matthew G Ondeck Laurent Fattet Spencer Wei Jing Yang Adam J Engler Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.