Newly emerged engineering of in vitro 3D tumor models using biomaterials for chemotherapy

Abstract Chemotherapy that relies on chemical agents to kill cancer cells is a widely used anticancer strategy. Development of chemotherapeutic drugs consumes a vast amount of time and funds, but is often frustrated by high-failure rates. One of the key reasons is a lack of proper models to dissect drug performance such as efficacy, toxicity, and resistance. With advances in micromachining and tissue engineering, in vitro three-dimensional (3D) tumor models engineered by microfluidics or 3D bioprinting have emerged to histologically and functionally resemble tumors in human body and precisely assess in vivo chemotherapy drug responses. This chapter introduces these 3D tumor models that utilize unique features provided by microfluidics and 3D bioprinting, and also discusses their applications and challenges in the field of chemotherapy.