Principles of Hanging Drop Method (Spheroid Formation) in Cell Culture.

A type of three-dimensional (3D) cell culture models which is simple and easy is hanging drop method. The hanging drop method emerges as a pivotal technique with diverse applications in cancer research and cell biology. This method facilitates the formation of multicellular spheroids, providing a unique environment for studying cell behavior dynamics. The hanging drop method's theoretical underpinning relies on gravity-enforced self-assembly, allowing for cost-effective, reproducible 3D cell cultures with controlled spheroid sizes. The advantages of this approach include its efficiency in producing cellular heterogeneity, particularly in non-adherent 3D cultures, and its ability to create hypoxic spheroids, making it a suitable model for studying cancer. Moreover, the hanging drop method has proven valuable in investigating various aspects such as tissue structure, signaling pathways, immune activation of cancer cells, and notably, cell proliferation. Researchers have utilized the hanging drop method to explore the dynamics of cell proliferation, studying the effects of mesenchymal stem cells (MSC) secretome on cancer cells. The method's application involves co-culturing different cell lines, assessing spheroid formations, and quantifying their sizes over time. These studies have unveiled intricate cell behavior dynamics, demonstrating how the MSC secretome influences cancer cell growth and viability within a three-dimensional co-culture paradigm.