abstract
Three-dimensional multicellular tumor models are receiving an ever-growing focus as preclinical drug screening platforms due to their potential to recapitulate major physiological features of human tumors in vitro. In line with this momentum, the technologies for assembly of 3D microtumors are rapidly evolving towards a comprehensive inclusion of tumor microenvironment elements. Customized spherically structured platforms, including microparticles and microcapsules, provide a robust and scalable technology to imprint unique biomolecular tumor microenvironment hallmarks into 3D in vitro models. Herein, a comprehensive overview of novel advances on the integration of tumor-ECM components and biomechanical cues into 3D in vitro models assembled in spherical shaped platforms is provided. Future improvements regarding spatiotemporal/mechanical adaptability, and degradability, during microtumors in vitro 3D culture are also critically discussed considering the realistic potential of these platforms to mimic the dynamic tumor microenvironment. From a global perspective, the production of 3D multi cellular spheroids with tumor ECM components included in spherical models will unlock their potential to be used in high-throughput screening of therapeutic compounds. It is envisioned, in a near future, that a combination of spherically structured 3D microtumor models with other advanced microfluidic technologies will properly recapitulate the flow dynamics of human tumors in vitro. Statement of Significance The ability to correctly mimic the complexity of the tumor microenvironment in vitro is a key aspect for the development of evermore realistic in vitro models for drug-screening and fundamental cancer biology studies. In this regard, conventional spheroid-based 3D tumor models, combined with spherically structured biomaterials, opens the opportunity to precisely recapitulate complex cell-extracellular matrix interactions and tumor compartmentalization. This review provides an in-depth focus on current developments regarding spherically structured scaffolds engineered into in vitro 3D tumor models, and discusses future advances toward all-encompassing platforms that may provide an improved in vitro/in vivo correlation in a foreseeable future. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
keywords
MESENCHYMAL STEM-CELLS; BREAST-CANCER CELLS; HYALURONIC-ACID; 3-DIMENSIONAL SCAFFOLDS; EXTRACELLULAR-MATRIX; PROSTATE-CANCER; SPHEROID FORMATION; CULTURE-SYSTEMS; DRUG DISCOVERY; STROMAL CELLS
subject category
Engineering; Materials Science
authors
Ferreira, LP; Gaspar, VM; Mano, JF
our authors
Projects
acknowledgements
The authors would like to acknowledge the support of the European Research Council grant agreement ERC for project ATLAS. This work was also developed under the support of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. The authors also acknowledge the financial support by the Foundation for Science and Technology (FCT) through a Post-doctoral grant (SFRH/BPD/119983/2016, Vitor Gaspar).