Fig. 1: GBM-on-a-chip.

a Schematic representation of a tumor cross-section depicting the hypoxic core and different biological components typically found in a tumor microenvironment. b Schematic illustration of the bioinks used to fabricate a compartmentalized GBM-on-a-chip model. c Mock representation of bioink compartments of brain dECM laden with HUVECs (depicted in magenta), and brain dECM with GBM cells (blue) shown from above (top) and from the corner (bottom; scale bar, 2 cm). d Computer simulation of oxygen gradient along A–A′ cross-section depicted by time-lapse jet colourmap images. e Schematic representation of the various regions within the printed GBM model (i) core, (ii) intermediate, (iii) peripheral regions, and (iv) the surrounding tissue region. f Fluorescent images of cross-section of immunostained tumor highlighting the hypoxic cells using pimonidazole (PM), Ki67 for the proliferating cells, and DAPI for the cell nuclei (scale bar, 200 μm.) (Reproduced/adapted with permission from ref. ²⁸).