TNNT1 and astrocytoma (excluding glioblastoma): Since their initial description in PC12 cells, TnTs have received several names in the scientific literature (cytonemas, intercellular nanotubes, filopodial bridges, and, more recently, tumour microtubes to define ultra-long, long-lived, and thick membrane extensions found in astrocytoma cells [13]) and have been shown to harbor different morphological and molecular properties in distinct cell types [33].