Exploring the local tumor infiltration of medulloblastoma into the adjacent brain tissue

Medulloblastoma (MB), one of the most common malignant brain tumors in children, is classified into four molecular types: Sonic Hedgehog (SHH), WNT, and non-WNT/non-SHH (group 3 and group 4). While subtype-specific metastasis patterns have been described, and metastasis at diagnosis is a negative prognostic factor for patient survival, local infiltration of MB into the surrounding brain tissue remains largely unexplored. This project aims at investigating the local infiltration of primary MB. By examining hematoxylin and eosin-stained sections from over 250 MB, we observed that local infiltration into the cerebellar tissue was more frequently displayed in SHH than WNT or non-WNT/non-SHH MB. Using single-nucleus RNA sequencing data, a various number of non-neoplastic cerebellar granule cells was detected in 17 of 93 MB samples (SHH, n=10; group 4, n=6; and WNT, n=1), with the presence of granule cells correlating with the histopathological evaluation. Ongoing efforts involve the generation of spatial transcriptomic data, assessing brain infiltration on MRI, and correlating our findings with clinical data to deepen our knowledge on the local tumor infiltration in MB.

Publication History

Article published online:
09 May 2025