Core–shell microbead-based 3D vascularized glioma tumor model for effective drug testing

The 3D hydrogel-based tumor model demonstrates significant potential in replicating the physiological characteristics of<i>in vivo</i>tumor environments for mechanistic studies and drug testing. However, the challenge persists in accurately mimicking a vascularized microtumor with a compartmentalized structure in a controlled, heterogeneous, and high-throughput manner. This study introduces a vascularized 3D tumor model that incorporates an endothelial cell (EC) barrier, created by encapsulating glioma cells and human umbilical vein endothelial cells (HUVECs) within the core (6% gelatin) and shell (10% GelMa) of core-shell microbeads, respectively. Upon culture, the tumor cells develop spheroids within the liquid core, while the HUVECs in the shell migrate and adhere to the GelMa surface, ultimately forming an EC barrier. This 3D microengineered tumor model exhibits angiogenesis in solid tumor spheroids, effectively mirroring the<i>in vivo</i>structure and providing relevant biochemical and biophysical properties. Notably, in comparison to 2D cell cultures, the vascularized tumor model shows significantly higher half-maximal inhibitory concentrations for the anticancer drug doxorubicin. Collectively, these findings highlight the considerable potential of engineered 3D tumor models in drug testing.