3D Cell Cultures as Prospective Models to Study Extracellular Vesicles in Cancer

Abstract

The improvement of culturing techniques to model the environment and physiological conditions surrounding tumors has also been applied to the study of extracellular vesicles (EVs) in cancer research. EVs role is not only limited to cell-to-cell communication in tumor physiology, they are also a promising source of biomarkers, and a tool to deliver drugs and induce antitumoral activity. In the present review, we have addressed the improvements achieved by using 3D culture models to evaluate the role of EVs in tumor progression and the potential applications of EVs in diagnostics and therapeutics. The most employed assays are gel-based spheroids, often utilized to examine the cell invasion rate and angiogenesis markers upon EVs treatment. To study EVs as drug carriers, a more complex multicellular cultures and organoids from cancer stem cell populations have been developed. Such strategies provide a closer response to in vivo physiology observed responses. They are also the best models to understand the complex interactions between different populations of cells and the extracellular matrix, in which tumor-derived EVs modify epithelial or mesenchymal cells to become protumor agents. Finally, the growth of cells in 3D bioreactor-like systems is appointed as the best approach to industrial EVs production, a necessary step toward clinical translation of EVs-based therapy.

In Vitro 3D Cultures to Model the Tumor Microenvironment

“…Likewise, hanging-drop techniques allow spheroid generation in the form of droplets: cancer cell suspensions are dispensed into the wells of a mini-tray that is subsequently reversed upside down, promoting tumoroid generation through the simultaneous action of surface tension and gravity. Notably, the dimensions of the spheroids can be controlled by changing the diameter of the droplets [26][27][28][29]. Finally, a new example of 3D technology is represented by the multichannel microfluidic perfusion culture system, also known as "organ-on-a-chip".…”

In vivo imaging of EVs in zebrafish: New perspectives from “the waterside”

“…This indicates that the spatial and geometric organization, and therefore the complex cell‐cell/cell‐ECM interactions impact the (sub)type of EVs that is secreted. It is clear that these 3D systems are a qualitative improvement over 2D systems and therefore rightly deserve more attention in EV research 49 . More recently, attempts have been made to visualize genetically tagged endogenous EVs released in simple 3D systems such as transwells to study the blood brain barrier, 50 and further improvement can be expected from live‐imaging of organoids or assembloids 44 .…”

“…It is clear that these 3D systems are a qualitative improvement over 2D systems and therefore rightly deserve more attention in EV research. 49 More recently, attempts have been made to visualize genetically tagged endogenous EVs released in simple 3D systems such as transwells to study the blood brain barrier, 50 and further improvement can be expected from live‐imaging of organoids or assembloids. 44 These approaches will help clarify how the architecture of an organoid impacts EV size and cargo at molecular level, in terms of mechanical triggers or biological cues that might impact EV biogenesis, cargo sorting, and endosomal trafficking.…”

3D Models as an Adjunct for Models in Studying Alzheimer's Disease

“…Also, the cell-cell interactions are less in 2D models compared to 3D models, and have been associated with further deviation from in vivo conditions. 35 Recent Studies Using 3D Models 3D models have been applied in various fields to understand disease processes as in the case of cancers or the genetic mechanisms for expression patterns. A recent study on hepatocellular cancer, for example, noted enhanced control of tumor microenvironments and showed interestingly similar treatment response as real-life representation of the cancer, when compared to monolayer 2D models.…”