PLXNB2 and neoplasm: Specifically, whereas in the control SD2 cohort, tumor cells had spread diffusely throughout the striatum and deep into the contralateral hemisphere along the corpus callosum by 147 dpi or 209 dpi, in the Plexin-B2 KO cohort, we observed that tumor cells remained close to the engraftment site, with few cells penetrating into contralateral hemisphere (Fig. 2c, d).