9 Projects Transforming the Field of NF1 Research

NTAP convenes symposiums on a regular basis to determine research priorities, define new avenues of inquiry and develop requests for applications (RFAs) in neurofibromatosis type-1 (NF1) research based on those identified areas for opportunity. Below are the nine projects that resulted from the 2016 Cutaneous Neurofibroma Symposium held in Landsdown, Virginia. These projects launched in 2018 and represent more than $3 million in investment in cutaneous neurofibroma (cNF) research. They include work that generated the first genetically engineered mouse models for cNF, identified the cell of origin for cNF, and created semi-immortalized cell lines and co-culture systems for cNF.

“Leveraging human induced pluripotent stem cells (iPSCs) to determine the impact of patient-derived NF1 gene mutations on peripheral sensory neuron-driven Schwann cell growth”
David Gutmann, MD, PhD
Washington University
St. Louis, Missouri
Dr. Gutmann and co-workers will investigate the impact and potential mechanism of peripheral neurons on NF1-deficient Schwann cell growth, with respect to : 1) Generating and characterizing sensory neurons from selected iPSCs, 2) Showing that sensory neurons with or without NF1 deletion have differential effects on SC which are NF1 expressing and non-expressing, and 3) Evaluating neurofibromin expression over multiple time points to determine if there are differential effects of neurofibromin on SC of various NF1 backgrounds over time. Study Description >

“Modeling cNF with human Schwann Cells via tunable and reversible control of NF1 protein”
Gabsang Lee, DVM, PhD
Johns Hopkins University
Baltimore, Maryland
Dr. Lee and co-workers will seek to understand the effect that neurofibromin protein expression levels at specific stages of Schwann cell development have on disease pathogenesis. The team will investigate the role of NF1 at different stages of neural crest/Schwann cell development by utilizing “isogenically paired” NF1+/+, NF1+/- and NF1-/- pluripotent stem cells, and SMASh (small molecule-assisted shutoff) tag methodology, which allows the tunable and reversible control protein production/degradation (such as NF1 protein). Study Description >

“Identification of pathways triggered by Schwann cell-fibroblast interactions driving cutaneous neurofibroma growth”
Edu Serra, PhD
The Institute for Health Science Research Germans Trias i Pujol (IGTP)
Barcelona, Spain
Dr. Serra and co-workers will explore in detail the role of heterotypic interactions between SC and fibroblasts on cNF pathogenesis. They will evaluate heterotypic interactions between SC and fibroblasts in cNFs to specifically identify the gene expression profiles produced, and dissect from the expression profiles which part is expressed by SC and which part by fibroblasts. Study Description >

“Use of the mouse model of cutaneous neurofibromas for identification of cells of origin and drug screening studies”
Piotr Topilko, Ph.D.
INSERM
Paris, France
The team led by Dr. Topilko will seek to utilize their newly developed genetically engineered mouse model of cNF based on Prss56Cre, NF1fl/-, R26tdTom to: 1) evaluate stromal changes in the progression from micro cNFs to cNFs, 2) identify the derivatives of neural-crest-derived basal cap cells that give rise to cNFs, and 3) test the efficacy of a MEK inhibitor (Selumetinib) in inhibiting or preventing formation of cNFs in the mouse model. Study Description >

“Cutaneous Neurofibroma: Models, Biology and Translation”
Lu Le, M.D., Ph.D.
University of Texas, Southwestern Medical Center
Dallas, Texas
Dr. Le and co-workers will utilize their genetically engineered mouse model of cNF based on Hoxb7-Cre; Nf1flox/flox to: 1) Identify the cNF cell of origin (from human iPSC) with focus on establishing the presence and location of HoxB7 in human cells and its characterization as a cell of origin marker, and 2) Conduct mouse xenograft studies involving murine derived SKPs with respect to the transplant of in vitro skin reconstructs into hormone-primed nude mice in vivo. Study Description >

“Genetic Studies of Neurofibromatosis”
Peggy Wallace, Ph.D.
University of Florida
Gainesville, Florida
Dr. Wallace and co-workers will investigate the genetic factors underlying the pathogenesis of cNFs with respect to: 1) Creation of semi-immortalized SC of various NF1 backgrounds (NF +/- vs. NF /) from heterogenous human cNFs, 2) Conduct of single cell authentication and exome RNA sequencing in the semi-immortalized Schwann cell lines and analysis to compare to results previously obtained from semi-immortalized SC from cutaneous neurofibromas, and 3) Evaluating intact cNFs (from primary samples) to ascertain an RNA signature from the SC in the setting of an intact microenvironment, with comparison back to the isolated primary and semi-immortalized SC. Study Description >

“Microenvironmental targets of cutaneous neurofibromas: T-cells and mast cells as tumor contributors”
Juha Peltonen, M.D., Ph.D., and Sirkku Peltonen, M.D.
University of Tirkku
Tirkku, Finland
Drs. Peltonen and co-workers will investigate the roles and effects of T-cells and mast cells as microenvironment components in promoting tumorigenesis with respect to: 1) characterization and quantification of T cells residing in cNFs, 2) evaluation of the clonality of T cells, 3) characterization and quantification of cNF mast cells by measuring relative abundancies of mast cell types, 4) studies on expression of NGF and receptors for progesterone and estrogen in cNF mast cells, and 5) evaluation of T-cell-Schwann cell interactions and mast cell-Schwann cell interactions by mass spectrometry. Study Description >

“A 3D Cutaneous Neurofibroma Model for Automated High-Throughput Drug Screenings”
Alice Soragni, Ph.D.
University of California, Los Angeles
Los Angeles, California
The Institute for Health Science Research Germans Trias i Pujol (IGTP) Study Description >

Dr. Soragni and co-workers will seek to develop and characterize a miniaturized 3D preclinical model (i.e. a ring organoid) for human cNF and then to validate the organoids by determining whether histopathology, transcriptional profile and pathway alterations of the 3D cNF organoids reflect the basic physiology of the tumor.

“Deconstruction and Reconstitution of NF1 Cutaneous Neurofibromas”
Ray Mattingly, Ph.D.
Wayne State University
Detroit, Michigan
Dr. Mattingly and co-workers will deconstruct human cNFs using single cell transcriptomics (via scRNA-Seq) to define cell populations involved in the tumor, and then develop pathomimetic avatars (based on those sub-populations) from which 3D co-culture models of the tumors will be developed for preclinical screening. Study Description >