Fig. 6: Assembly of 3D-printed minibeam collimator and its microenvironmental modulation in TNBC tumors.

The upper left section illustrates the manufacturing process of the 3D-printed components, including the PLA sheet, slide groove, and clip. These components are then assembled with tungsten plates. The middle shows the assembled microbeam collimator, the main body of which is a sandwich structure. The upper right section illustrates the radiotherapy process using the collimator in small animal models. The lower section presents a schematic representation of how MBRT influences the tumor microenvironment, highlighting its mechanism of reducing tumor angiogenesis and alleviating hypoxia by inhibiting the HIF-1α/VEGFR signaling axis.