Characterization of multicellular breast tumor spheroids using image data-driven biophysical mathematical modeling

Abstract

Multicellular tumor spheroid (MCTS) systems provide an in vitro cell culture model system which mimics many of the complexities of an in vivo solid tumor and tumor microenvironment, and are often used to study cancer cell growth and drug efficacy. Here, we present a coupled experimental-computational framework to estimate phenotypic growth and biophysical tumor microenvironment properties. This novel framework utilizes standard microscopy imaging of MCTS systems to drive a biophysical mathematical model of MCTS growth and mechanical interactions. By extending our previous in vivo mechanically-coupled reaction–diffusion modeling framework we developed a microscopy image processing framework capable of mechanistic characterization of MCTS systems. Using MDA-MB-231 breast cancer MCTS, we estimated biophysical parameters of cellular diffusion, rate of cellular proliferation, and cellular tractions forces. We found significant differences in these model-based biophysical parameters throughout the treatment time course between untreated and treated MCTS systems, whereas traditional size-based morphometric parameters were inconclusive. The proposed experimental-computational framework estimates mechanistic MCTS growth and invasion parameters with significant potential to assist in better and more precise assessment of in vitro drug efficacy through the development of computational analysis methodologies for three-dimensional cell culture systems to improve the development and evaluation of antineoplastic drugs.

Spatial-temporal analysis of nanoparticles in live tumor spheroids impacted by cell origin and density

“…Calculating the penetration kinetics of nanoparticles in cancer spheroids or organoids is an important step towards robust evaluation of nanoparticle uptake and falls under the drive toward consistent and reproducible reporting in bio-nano literature, for the direct comparison of nanoparticle designs between different studies [19,35]. We further validated the nanoparticle kinetic findings by incorporating mathematical modelling into our analysis, which has previously been used to investigate how nanoparticle characteristics influence cell uptake, or how tumor spheroid development may impact drug delivery, both in a high throughput and iterative manner [48][49][50][51].…”

Fluorescence Microscopy—An Outline of Hardware, Biological Handling, and Fluorophore Considerations

“…These experiments were performed using morphometric analysis, with DAPI and F-actin fluorescence, to determine that the features that best described the compound-induced morphological changes are total organoid size, shape and size of lumen, live/dead cell counts, and changes in nucleus morphology [ 60 ]. Spheroid-derived image data are then used to produce characterisation methods that estimate growth and biophysical characteristics of multicellular tumour spheroids [ 61 ]. Using these spheroids, changes in cellular density and mechanical interactions are characterised, helping estimate cell diffusion, proliferation, and traction forces exerted by cells on the surrounding extracellular matrix [ 61 , 62 ].…”

“…Spheroid-derived image data are then used to produce characterisation methods that estimate growth and biophysical characteristics of multicellular tumour spheroids [ 61 ]. Using these spheroids, changes in cellular density and mechanical interactions are characterised, helping estimate cell diffusion, proliferation, and traction forces exerted by cells on the surrounding extracellular matrix [ 61 , 62 ]. The development of such protocols will be of significant benefit to the use of 3D culture in studying responses to therapeutics; however, there remains a need to investigate spheroids at a subcellular level to elucidate phenotypic changes occurring due to cell–cell interactions.…”

Three-Dimensional Culture Models to Study Innate Anti-Tumor Immune Response: Advantages and Disadvantages

“…Standardization is easier, having a lot of replicates of the immune-tumor cell interaction, when NK cells are faced with a spheroid of a defined size. Indeed, standardization is a key point to translate in vitro data to the clinic [ 155 , 156 , 157 , 158 , 159 ]. However, the use of spheroids of different size can characterize the behavior of NK cells when challenged with tumors showing different mass density, or inner hypoxic areas [ 126 ].…”