Neurofibromatosis 1 Somatic Mutation Triggering Cellular Apoptosis to Prevent Neurofibromatosis 1 Progression

Crossmark: check for updates

Authors

  • Vincent M. Riccardi, MD, MBA The Neurofibromatosis Institute, 5415 Briggs Avenue, La Crescenta, CA 91214, USA

DOI:

https://doi.org/10.17140/NOJ-7-e011

Keywords:

chromosome, diploinsufficiency

Abstract

Persons with ordinary, prototypical Neurofibromatosis 1 (NF1)
are born with a germinal/zygotic mutation at the NF1 locus
on the long arm of chromosome 17 (17q) present in all of their
cells. An NF1 germinal mutation is the “first hit,” accounting for
haploinsufficiency at the NF1 locus. The NF1 somatic mutation
is the “second hit,” accounting for diploinsufficiency (deranged or
lost function of both alleles) at the NF1 locus. The NF1 somatic
mutation occurs in a variety of somatic (i.e., non-germinal) cells,
including, and especially the schwann cells (SC). I suggest that
NF1 haploinsufficiency provides the conditions for the SC (and
other cells) to develop NF1 diploinsufficiency rather than NF1
diploinsufficiency developing independently of the conditions in
which it originates. In either case, imagine a viral analogue with an
apoptosis trigger held in abeyance unless an NF1 somatic mutation
occurs in the presence of an NF1 germinal mutation or whole
gene deletion. That is, instead of altering the feature, for example,
decreasing neurofibroma size and symptoms with MEK inhibitors,
I herein suggest an approach to preventing certain NF1 features,
keying off the fact that almost NF1 features involve somatic
mutation of the cell’s NF1 wild type (WT) allele.

References

Riccardi VM. Neurofibromatosis type 1 is a disorder of dysplasia: The importance of distinguishing features, consequences, and complications. Birth Defects Res A Clin Mol Teratol. 2010; 88: 9-14. doi: 10.1002/bdra.20616

Rice FL, Houk G, Wymer JP, et al. The evolution and multi-molecular properties of NF1 cutaneous neurofibromas originating from C-fiber sensory endings and terminal Schwann cells at normal sites of sensory terminations in the skin. PLoS One. 2019; 14: e0216527. doi: 10.1371/journal.pone.0216527

Riccardi VM. Ketotifen suppression of NF1 neurofibroma growth over 30 years. Am J Med Genet A. 2015; 167(7): 1570-1577. doi: 10.1002/ajmg.a.37045

Jaakkola S, Peltonen J, Riccardi V, Chu ML, Uitto J. Type 1 neurofibromatosis: Selective expression of extracellular matrix genes by Schwann cells, perineurial cells, and fibroblasts in mixed cultures. J Clin Invest. 1989; 84: 253-261. doi: 10.1172/JCI114148

Amoh Y, Li L, Campillo R, et al. Implanted hair follicle stem cells form Schwann cells that support repair of severed peripheral nerves. Proc Nat Acad Sci U S A. 2005; 102: 17734-17738. doi: 10.1073/pnas.0508440102

Tucker T, Riccardi VM, Brown C, et al. S100B and neurofibromin immunostaining and X-inactivation patterns of laser microdissected cells indicate a multicellular origin of some NF1-associated neurofibromas. J Neurosci Res. 2011; 89: 1451-160. doi: 10.1002/jnr.22654

Riccardi VM. Translational genetics and genomics: The fundamental nature of NF1 neurofibromas. J Transl Genet Genom. 2017; 1: 1-12.

Suzuki K, Tsunekawa Y, Hernandez-Benitez R, et al. In vivo genome editing via CRISPR/Cas9 mediated homology-independent targeted integration. Nature. 2016; 540: 144-149. doi: 10.1038/nature20565

Zhang Y, Long C, Li H, et al. CRISPR-Cpf1 correction of muscular dystrophy mutations in human cardiomyocytes and mice. Science Advances. 2017; 3: e1602814. doi: 10.1126/sciadv.1602814

Matharu N, Rattanasopha S, Tamura S, et al. CRISPR-mediated activation of a promoter or enhancer rescues obesity caused by haploinsufficiency. Science. 2019; 363(6424): eaau0629. doi: 10.1126/science.aau0629 Editorial | Volume 7 | Issue 1|

Published

2020-05-13

How to Cite

Vincent M. Riccardi, MD, MBA. (2020). Neurofibromatosis 1 Somatic Mutation Triggering Cellular Apoptosis to Prevent Neurofibromatosis 1 Progression. Neuro, 7(1), 9–10. https://doi.org/10.17140/NOJ-7-e011

Issue

Section

Articles