HHIP and neoplasm: By contrast, clusters 1, 3, 4, and 6 expressed more mature neuronal markers such as GRIA2 (glutamate receptor), PAX6 (cerebellar granule cell marker), and NRXN1 (cell adhesion molecule found on pre-synaptic membranes) and were therefore termed “Intermediate” or “Late/Neuronal-like.” Interestingly, the expression of both SFRP1 and HHIP, reported to have tumor suppressor functions29–31—the former being the target of SHH signaling and the latter being a negative regulator of the SHH pathway—was lost in those clusters (Supplementary Figure 4B, Supplementary Table 3).