non-NF2 meningioma  

NEUROLOGY, PATHOLOGY

A self explanatory term for a meningioma lacking a mutation in NF2.* Non-NF2 meningiomas are nearly always benign, have genomic stability, and arise from the medial skull base, in contrast to NF2 meningiomas which are more often atypical, have genomic instability and localise to the cerebral and cerebellar hemispheres.

Non-NF2 meningiomas lack the NF2 mutation, but have mutations in other genes, including TRAF7, a proapoptotic E3 ubiquitin ligase–it is commonly associated with a recurrent mutation in KLF4, a transcription factor that induces pluripotency, or in AKT1^E17K, a mutation that activates the PI3K pathway. Mutations of SMO, which activates Hedgehog signaling, are seen in 5% of non-NF2 mutant meningiomas. The differences between non-NF2 and NF2 meningiomas may provide “hooks” for targeted therapeutics.

*The gene that encodes neurofibromin 2–aka, merlin, a putative regulator of the Hippo/SWH (Sav/Wts/Hpo) signaling pathway, which plays a key role in tumour suppression by restricting proliferation and promoting apoptosis.

Reference Science 1 March 2013: Vol. 339 no. 6123 pp. 1077-1080

DOI: 10.1126/science.1233009