The Tropism of Pleiotrophin: Orchestrating Glioma Brain Invasion.

The lateral ventricle (LV) is a preferential location for brain tumor spread; however, the instructive cues responsible for this unique tropism were previously unknown. In this issue, Qin et al. elucidate the underlying mechanism, demonstrating that LV-neural progenitors secrete a pleiotrophin (PTN)-containing complex, which attracts glioma cells through ROCK/Rho activation.