In Vitro Cancer Model for Drug Testing

During the process of anticancer drug discovery and preclinical testing research, a more physiological in vitro cancer model can provide more reliable data. Due to the three-dimensional (3D) nature of tumor structure, significant discrepancy in drug efficiency was found when compared between in vivo testing and the widely used monolayer culture approach. Therefore, 3D culture models, which can reflect the natural features of a tumor, became the key elements in tumor biology and anticancer reagent research fields. It is believed that 3D culture can mimic the in vivo tumor microenvironment and is helpful in understanding cell–cell interaction, cell–matrix interaction, tumor cell differentiation, migration, and invasion processes. Various 3D models are developed, focusing on different interests, and applied in many branches of biomedical science. When employing 3D models for anticancer drug testing, the drug efficiency is significantly lower than in the monolayer culture. This could explain why drug applying to clinic, with recommended dose obtained from two-dimensional (2D) testing, is always insufficient. The advanced 3D models and tissue-engineering techniques made tumor models even more complex, having more tumor features such as blood vessels or stroma, and more similar to the real solid tumor. The cancer models with these tumor-like features could provide reliable preclinical proof during the chemotherapy reagent discovery phase.