title: Gelatine methacrylamide-based hydrogels: an alternative three-dimensional cancer cell culture system.
abstract: Modern cancer research requires physiological, three-dimensional (3-D) cell culture platforms, wherein the physical and chemical characteristics of the extracellular matrix (ECM) can be modified. In this study, gelatine methacrylamide (GelMA)-based hydrogels were characterized and established as in vitro and in vivo spheroid-based models for ovarian cancer, reflecting the advanced disease stage of patients, with accumulation of multicellular spheroids in the tumour fluid (ascites). Polymer concentration (2.5-7% w/v) strongly influenced hydrogel stiffness (0.5±0.2kPa to 9.0±1.8kPa) but had little effect on solute diffusion. The diffusion coefficient of 70kDa fluorescein isothiocyanate (FITC)-labelled dextran in 7% GelMA-based hydrogels was only 2.3 times slower compared to water. Hydrogels of medium concentration (5% w/v GelMA) and stiffness (3.4kPa) allowed spheroid formation and high proliferation and metabolic rates. The inhibition of matrix metalloproteinases and consequently ECM degradability reduced spheroid formation and proliferation rates. The incorporation of the ECM components laminin-411 and hyaluronic acid further stimulated spheroid growth within GelMA-based hydrogels. The feasibility of pre-cultured GelMA-based hydrogels as spheroid carriers within an ovarian cancer animal model was proven and led to tumour development and metastasis. These tumours were sensitive to treatment with the anti-cancer drug paclitaxel, but not the integrin antagonist ATN-161. While paclitaxel and its combination with ATN-161 resulted in a treatment response of 33-37.8%, ATN-161 alone had no effect on tumour growth and peritoneal spread. The semi-synthetic biomaterial GelMA combines relevant natural cues with tunable properties, providing an alternative, bioengineered 3-D cancer cell culture in in vitro and in vivo model systems.
authors.affiliation: Regenerative Medicine Program, Institute of Health and Biomedical Innovation, 60 Musk Ave, Kelvin Grove 4059 QLD, Brisbane, Australia; Faculty of Science and Engineering, Queensland University of Technology, Brisbane, Australia; Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany.
authors.forename: Elke
authors.initials: E
authors.lastname: Kaemmerer
authors.affiliation: Regenerative Medicine Program, Institute of Health and Biomedical Innovation, 60 Musk Ave, Kelvin Grove 4059 QLD, Brisbane, Australia; Faculty of Science and Engineering, Queensland University of Technology, Brisbane, Australia; Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Ferry P W
authors.initials: FP
authors.lastname: Melchels
authors.affiliation: Regenerative Medicine Program, Institute of Health and Biomedical Innovation, 60 Musk Ave, Kelvin Grove 4059 QLD, Brisbane, Australia; Faculty of Science and Engineering, Queensland University of Technology, Brisbane, Australia; Orthopaedic Center for Musculoskeletal Research, Department of Orthopaedic Surgery, Julius-Maximilians-University Würzburg, Würzburg, Germany.
authors.forename: Boris M
authors.initials: BM
authors.lastname: Holzapfel
authors.affiliation: Membrane Dynamics, Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Meckel
authors.affiliation: Regenerative Medicine Program, Institute of Health and Biomedical Innovation, 60 Musk Ave, Kelvin Grove 4059 QLD, Brisbane, Australia; Faculty of Science and Engineering, Queensland University of Technology, Brisbane, Australia.
authors.forename: Dietmar W
authors.initials: DW
authors.lastname: Hutmacher
authors.affiliation: Cancer Program, Institute of Health and Biomedical Innovation, 60 Musk Ave, Kelvin Grove 4059 QLD, Brisbane, Australia; Faculty of Health, Queensland University of Technology, Brisbane, Australia. Electronic address: daniela.lossner@qut.edu.au.
authors.forename: Daniela
authors.initials: D
authors.lastname: Loessner
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D002455:Cell Division; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000201:enzymology / Q000378:metabolism; D005780:Gelatin / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels; D020782:Matrix Metalloproteinases / Q000187:drug effects
chemical_list: D000178:Acrylamides; D020100:Hydrogels; D005780:Gelatin; D020782:Matrix Metalloproteinases; C045985:methacrylamide
keywords: Animal model; Cell encapsulation; ECM; Hydrogel; Mechanical properties