title: Microenvironment complexity and matrix stiffness regulate breast cancer cell activity in a 3D in vitro model.
abstract: Three-dimensional (3D) cell cultures represent fundamental tools for the comprehension of cellular phenomena both in normal and in pathological conditions. In particular, mechanical and chemical stimuli play a relevant role on cell fate, cancer onset and malignant evolution. Here, we use mechanically-tuned alginate hydrogels to study the role of substrate elasticity on breast adenocarcinoma cell activity. The hydrogel elastic modulus (E) was measured via atomic force microscopy (AFM) and a remarkable range (150-4000 kPa) was obtained. A breast cancer cell line, MCF-7, was seeded within the 3D gels, on standard Petri and alginate-coated dishes (2D controls). Cells showed dramatic morphological differences when cultured in 3D versus 2D, exhibiting a flat shape in both 2D conditions, while maintaining a circular, spheroid-organized (cluster) conformation within the gels, similar to those in vivo. Moreover, we observed a strict correlation between cell viability and substrate elasticity; in particular, the number of MCF-7 cells decreased constantly with increasing hydrogel elasticity. Remarkably, the highest cellular proliferation rate, associated with the formation of cell clusters, occurred at two weeks only in the softest hydrogels (E = 150-200 kPa), highlighting the need to adopt more realistic and a priori defined models for in vitro cancer studies.
authors.affiliation: National Council of Research (CNR) - IEIIT Institute, Genoa, 16149, Italy.|University of Genoa - Department of Biophysical and Electronic Engineering (DIBRIS), Genoa, 16145, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Cavo
authors.affiliation: National Council of Research (CNR) - IEIIT Institute, Genoa, 16149, Italy.|University of Genoa - Department of Biophysical and Electronic Engineering (DIBRIS), Genoa, 16145, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Fato
authors.affiliation: University of Genoa - Department of Biophysical and Electronic Engineering (DIBRIS), Genoa, 16145, Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Peñuela
authors.affiliation: National Council of Research (CNR) - IEIIT Institute, Genoa, 16149, Italy.|University of Genoa - Department of Biophysical and Electronic Engineering (DIBRIS), Genoa, 16145, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Beltrame
authors.affiliation: University of Genoa - Department of Biophysical and Electronic Engineering (DIBRIS), Genoa, 16145, Italy.|National Council of Research (CNR) - IBF Institute, Genoa, 16149, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Raiteri
authors.affiliation: National Council of Research (CNR) - IEIIT Institute, Genoa, 16149, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Scaglione
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000464:Alginates / Q000737:chemistry; D001943:Breast Neoplasms / Q000473:pathology*; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D019070:Cell Lineage; D049109:Cell Proliferation; D002470:Cell Survival; D016000:Cluster Analysis; D055119:Elastic Modulus; D004548:Elasticity; D005260:Female; D005434:Flow Cytometry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D066298:In Vitro Techniques; D061986:MCF-7 Cells; D018625:Microscopy, Atomic Force; D011312:Pressure; D023822:Tissue Engineering / Q000379:methods; D059016:Tumor Microenvironment
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020100:Hydrogels; D020723:Glucuronic Acid