Abstract The dynamic tumor microenvironment (TME) where cells continuously communicate, migrate, and react to each other and the signals that are secreted, is critical for inducing tumor progression and aggressiveness of most forms of cancer. We have special interest in glioblastoma (GBM) that displays a dynamic and complex TME for which we have developed the necessary tools to dissect it, understand it, and have a positive impact on its treatment. As such, it is necessary to understand the underlying biology in a dynamic and relevant environment. With various degrees of limitation pertaining to currently available in vitro and in vivo models, in this proposal, we aim to leverage our expertise to optimize a unique three-dimensional (3D) human mini-GBM model through the utilization of a light-based bioprinting technology and taking advantage of primary neuronal, vascular, and GBM cells, to more precisely replicate the brain TME in human patients. It is anticipated that, construction of an in vitro 3D human mini-GBM model mimicking not only the cellular compositions but also the extracellular matrix (ECM) properties and importantly, tissue architecture of its in vivo counterpart, will allow us to precisely assess proliferation, migration, and transformation of GBM cells, similar to those already proven in ex vivo GBM organotypic cultures but at much higher availability and throughput for potential drug screening in the future.