In Vitro Magnetic Techniques for Investigating Cancer Progression

SIMPLE SUMMARY: This review focuses on the advantages achieved by incorporating magnetic forces into culture platforms used to study cancer progression in the laboratory. Due to the complex interactions that occur between cancer cells and their environment throughout primary tumor growth and metastatic spread, benchtop techniques are essential for decoupling these factors at several stages of disease progression where traditional animal models would fail. Breakthroughs in our understanding of cancer biology and mechanics through these benchtop techniques can ultimately lead to better-designed precision medicine platforms and clinical therapeutics for patients. ABSTRACT: Worldwide, there are currently around 18.1 million new cancer cases and 9.6 million cancer deaths yearly. Although cancer diagnosis and treatment has improved greatly in the past several decades, a complete understanding of the complex interactions between cancer cells and the tumor microenvironment during primary tumor growth and metastatic expansion is still lacking. Several aspects of the metastatic cascade require in vitro investigation. This is because in vitro work allows for a reduced number of variables and an ability to gather real-time data of cell responses to precise stimuli, decoupling the complex environment surrounding in vivo experimentation. Breakthroughs in our understanding of cancer biology and mechanics through in vitro assays can lead to better-designed ex vivo precision medicine platforms and clinical therapeutics. Multiple techniques have been developed to imitate cancer cells in their primary or metastatic environments, such as spheroids in suspension, microfluidic systems, 3D bioprinting, and hydrogel embedding. Recently, magnetic-based in vitro platforms have been developed to improve the reproducibility of the cell geometries created, precisely move magnetized cell aggregates or fabricated scaffolding, and incorporate static or dynamic loading into the cell or its culture environment. Here, we will review the latest magnetic techniques utilized in these in vitro environments to improve our understanding of cancer cell interactions throughout the various stages of the metastatic cascade.