title: Inherent interfacial mechanical gradients in 3D hydrogels influence tumor cell behaviors.
abstract: Cells sense and respond to the rigidity of their microenvironment by altering their morphology and migration behavior. To examine this response, hydrogels with a range of moduli or mechanical gradients have been developed. Here, we show that edge effects inherent in hydrogels supported on rigid substrates also influence cell behavior. A Matrigel hydrogel was supported on a rigid glass substrate, an interface which computational techniques revealed to yield relative stiffening close to the rigid substrate support. To explore the influence of these gradients in 3D, hydrogels of varying Matrigel content were synthesized and the morphology, spreading, actin organization, and migration of glioblastoma multiforme (GBM) tumor cells were examined at the lowest (<50 µm) and highest (>500 µm) gel positions. GBMs adopted bipolar morphologies, displayed actin stress fiber formation, and evidenced fast, mesenchymal migration close to the substrate, whereas away from the interface, they adopted more rounded or ellipsoid morphologies, displayed poor actin architecture, and evidenced slow migration with some amoeboid characteristics. Mechanical gradients produced via edge effects could be observed with other hydrogels and substrates and permit observation of responses to multiple mechanical environments in a single hydrogel. Thus, hydrogel-support edge effects could be used to explore mechanosensitivity in a single 3D hydrogel system and should be considered in 3D hydrogel cell culture systems.
authors.affiliation: William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, United States of America.
authors.forename: Shreyas S
authors.initials: SS
authors.lastname: Rao
authors.forename: Sarah
authors.initials: S
authors.lastname: Bentil
authors.forename: Jessica
authors.initials: J
authors.lastname: DeJesus
authors.forename: John
authors.initials: J
authors.lastname: Larison
authors.forename: Alex
authors.initials: A
authors.lastname: Hissong
authors.forename: Rebecca
authors.initials: R
authors.lastname: Dupaix
authors.forename: Atom
authors.initials: A
authors.lastname: Sarkar
authors.forename: Jessica O
authors.initials: JO
authors.lastname: Winter
mesh_terms: D000199:Actins / Q000378:metabolism; D002448:Cell Adhesion; D018929:Cell Culture Techniques / Q000379:methods*; D002465:Cell Movement; D049109:Cell Proliferation; D048430:Cell Shape; D060833:Cellular Microenvironment; D003094:Collagen / Q000737:chemistry; D004338:Drug Combinations; D055119:Elastic Modulus; D005109:Extracellular Matrix / Q000378:metabolism; D005898:Glass / Q000737:chemistry; D005909:Glioblastoma / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D007797:Laminin / Q000737:chemistry; D040542:Mechanotransduction, Cellular; D011509:Proteoglycans / Q000737:chemistry; D014407:Tumor Cells, Cultured
chemical_list: D000199:Actins; D004338:Drug Combinations; D020100:Hydrogels; D007797:Laminin; D011509:Proteoglycans; C059485:matrigel; D003094:Collagen