title: Cell elasticity with altered cytoskeletal architectures across multiple cell types.
abstract: The cytoskeleton is primarily responsible for providing structural support, localization and transport of organelles, and intracellular trafficking. The structural support is supplied by actin filaments, microtubules, and intermediate filaments, which contribute to overall cell elasticity to varying degrees. We evaluate cell elasticity in five different cell types with drug-induced cytoskeletal derangements to probe how actin filaments and microtubules contribute to cell elasticity and whether it is conserved across cell type. Specifically, we measure elastic stiffness in primary chondrocytes, fibroblasts, endothelial cells (HUVEC), hepatocellular carcinoma cells (HUH-7), and fibrosarcoma cells (HT 1080) subjected to two cytoskeletal destabilizers: cytochalasin D and nocodazole, which disrupt actin and microtubule polymerization, respectively. Elastic stiffness is measured by atomic force microscopy (AFM) and the disruption of the cytoskeleton is confirmed using fluorescence microscopy. The two cancer cell lines showed significantly reduced elastic moduli values (~0.5kPa) when compared to the three healthy cell lines (~2kPa). Non-cancer cells whose actin filaments were disrupted using cytochalasin D showed a decrease of 60-80% in moduli values compared to untreated cells of the same origin, whereas the nocodazole-treated cells showed no change in elasticity. Overall, we demonstrate actin filaments contribute more to elastic stiffness than microtubules but this result is cell type dependent. Cancer cells behaved differently, exhibiting increased stiffness as well as stiffness variability when subjected to nocodazole. We show that disruption of microtubule dynamics affects cancer cell elasticity, suggesting therapeutic drugs targeting microtubules be monitored for significant elastic changes.
authors.affiliation: Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA 19104, United States; Department of Anesthesiology and Critical Care, School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, Philadelphia, PA 19104, United States.
authors.forename: Martha E
authors.initials: ME
authors.lastname: Grady
authors.affiliation: Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Pennsylvania, 3231 Walnut Street, Philadelphia, PA 19104, United States.
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Composto
authors.affiliation: Department of Anesthesiology and Critical Care, School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, Philadelphia, PA 19104, United States. Electronic address: David.Eckmann@uphs.upenn.edu.
authors.forename: David M
authors.initials: DM
authors.lastname: Eckmann
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000648:ultrastructure*; D000199:Actins / Q000648:ultrastructure*; D002460:Cell Line; D015638:Cytochalasin D / Q000494:pharmacology*; D004548:Elasticity; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects; D006801:Humans; D008870:Microtubules / Q000648:ultrastructure*; D015739:Nocodazole / Q000494:pharmacology
chemical_list: D000199:Actins; D015638:Cytochalasin D; D015739:Nocodazole
keywords: Atomic force microscopy; Cancer; Cell mechanics; Cytoskeleton; Elasticity