3D cell culture is an environment that allows cells to grow and interact in three dimensions with the extracellular matrix. In comparison, traditional 2D cell cultures involve cells growing as a flat monolayer on a plate. 3D cell cultures can be scaffold-based or scaffold-free. 3D cell culture has enabled researchers to study various aspects of cell behavior, including cell morphology, differentiation, proliferation, invasion, migration, protein synthesis, and gene expression.