GBM invasiveness rates vary significantly in humans, and we replicated this phenomenon in our finding that local cortical tumor infiltration dynamics were not sustained into late stages (as opposed to the 3xCR model, Fig. 3) when we added overexpression of a single glypican gene linked to synaptogenesis (GPC6) to the IUE CRISPR construct. Here, GPC1 is linked to neoplasm.