For example, the top upregulated pathways were associated with transcriptional targets of AP1 (Activator Protein-1) family member transcription factors FOSL1 and FOSL2. Interestingly, AP1 transcription factors FOS and Fra1 were found to be upregulated in pilocytic astrocytomas (85). Here, FOSL2 is linked to pilocytic astrocytoma.