FIGURE 7.

The Dual Role Of Nbs1 in Sonic Hedgehog (SHH)‐medulloblastoma (MB). In cancer prone SmoA1‐Granule Cell Progenitors (GCPs), Nbn ^KO causes reduced proliferation and increased cell death, ultimately leading to inhibition of MB development due to activation of the DNA damage response (DDR) and impairment of the SHH pathway. Whether these two events are linked or fully independent is currently not known. On the other hand, Nbn hemizygosis (Nbn ^HZ) causes DDR activation and a Notch‐dependent increase in clonogenic capability, favouring GCP transformation. These results, collectively, indicate a gene dosage‐dependent function of Nbn in SHH‐driven tumorigenesis.