Open Proposal Program

In addition to solicited requests for applications associated with specific research initiatives, NTAP also invites proposals from all investigators (regardless of their location or primary research focus) who have independent research projects designed to accelerate the development of effective treatments for plexiform neurofibromas (pNFs). We constantly strive to broaden the strategies applied to pNF research and to engage researchers from diverse areas to participate in our programs.

Current NTAP-funded Open Proposal Projects:

A Robust Plexiform Neurofibroma Model for Preclinical Drug Screening

Lu Le, M.D., Ph.D.. (University of Texas Southwestern Medical Center)

Dr. Le proposes to establish the utility of this non-germline plexiform neurofibroma (pNF) model as a rapid preclinical therapeutic drug screening tool to identify effective therapies for pNF.  To achieve this goal, Le and his team will first explore the possibility of long term storage of DNSCs to maintain their tumorigenic potential for reliable and rapid plexiform neurofibromagenesis. Next, they will develop it into a robust plexiform neurofibroma model for preclinical drug screening by testing therapeutic effects of different pharmacological interventions.

Narrative: Read about the project’s background, goals, methods, preliminary data, and progress to date (auspices of Dr. Lu Le,

Modeling signaling networks of NF1-deficient Schwann cells and plexiform neurofibromas using mass spectrometry-based proteomics

James Walker, Ph.D. (Massachusetts General Hospital)

Dr. Walker aims to identify putative proteomic and/or phosphoproteomic signatures associated with loss of NF1. Recent advances in mass-spectrometry (MS)-based proteomics permit the determination of the extent, localization, and site-specific stoichiometry of protein phosphorylation. We propose using two complementary MS-based approaches to define (i) the proteome and phosphoproteome and (ii) the activated kinome signature of NF1-deficient Schwann cells (SCs). Walker’s team will perform analyses on a panel of SC lines derived from PNs. Transcriptome profiling of cell lines will complement these data sets, together providing a detailed view of the cellular signaling networks and the molecular targets controlled by neurofibromin in a cell-type relevant to the disease. Finally, Walker’s team  will use small molecule inhibitors to both known and any novel signaling pathways we identify to examine the adaptive kinome in treated cell lines. Combining the use of a novel panel of cell lines with the sensitivity of high-end MS, they expect to identify signaling pathways and targets previously implicated as being important in NF1-associated tumors, as well as new and unexpected targets downstream of NF1.

Narrative: Read about the project’s background, goals, specific aims, and impact (auspices of Dr. James Walker,

TRAPping the metabolic adaptations of plexiform neurofibroma

Giorgio Colombo, Ph.D. (Institute of Chemistry of Molecular Recognition, Milan, Italy) and Andrea Rasola, Ph.D., M.S. (University of Padua, Italy)

This project aims at investigating the possibility that hyperactive Ras/ERK signalling could contribute to pro-neoplastic metabolic rearrangements in mitochondria of neurofibroma cells by regulating TRAP1 chaperone activity, thus crucially contributing to the processes of growth and malignant transformation of PNs. Colombo and Rasola will dissect the mode of action of TRAP1, connecting it with the metabolic status of PNs and MPNSTs, which will be thoroughly investigated in in vivo tumor models.

Narrative: Read about the project’s background, goals, methods, and impact (auspices of Dr. Giorgio Colombo,; Dr. Andrea Rasola,

Using PNF-derived NF1(+/-) and NF1 (-/-) iPS Cells: Understanding PNF-cell of Origin, First Steps in Malignant Progression and Specific Inhibition of NF1 (-/-) Cell Proliferation

Edu Serra, Ph.D. (IGTP, Barcelona, Spain)

The primary goals of this project are (1) to set up in vitro conditions to efficiently differentiate iPS cells into cells of the Neural Crest-Schwann cell lineage, (2) to characterize the methylome and transcriptome of these cells with distinct NF1 genotypes and test their potential engraftment/tumor formation capacity, and (3)
to generate new iPSC and edit control iPSC with distinct NF1 genotypes to interrogate the presence of epigenetic memory in the PNF-derived iPS cells generated.

Narrative: Read about the project’s background, goals, methods, preliminary results, and progress to date (auspices of Dr. Edu Serra,

Acceptance and Commitment Training for Adolescents and Young Adults with Neurofibromatosis Type 1, Plexiform Neurofibromas, and Chronic Pain: A Phase III Clinical Trial

Martin--for-webStaci Peron Martin, Ph.D. (NIH, National Cancer Institute)

The primary objective of this project is to evaluate whether patients receiving an Acceptance and Commitment Training (ACT) intervention demonstrate improved outcomes on a measure of pain interference (Pain Interference Index) when compared to a wait-list comparison group in adolescents and young adults with NF1 and PNs who experience chronic pain that interferes with daily functioning.

Narrative: Read about the project’s background, goals, preliminary results, and progress to date (auspices of Dr. Staci Martin,

Search of the molecular mechanisms sustaining plexiform neurofibroma formation in a novel three-dimensional in vitro model

Federica Chiara, Ph.D. (University of Padua, Italy)

This project’s primary goal is to determine the role of the Extracellular Matrix (ECM) in the neoplastic transformation of Schwann cells (SCs). The in vitro systems investigated will enable discovery of the ECM influence on Schwann cell progression toward malignancy in plexiform neurofibromas and its importance in/for drug screening.

Narrative: Read about the project’s background, goals, specific aims, and impact (auspices of Dr. Federica Chiara,

Testing the Pharmacologic role of Molecular Target inhibition on Plexiform Neurofibromas in a Genetically Engineered Mouse Model that closely Phenocopies Human Neurofibromatosis Type 1

 D. Wade Clapp, M.D. (Indiana University)

The goal of this project is to evaluate the therapeutic efficacy of various AAV serotypes, a TGF- β inhibitor, a VEGF inhibitor and a VEGFR inhibitor against existing plexiform neurofibromas utilizing a novel genetically engineered mouse model of plexiform neurofibroma.  The studies being conducted are highly significant from both scientific and clinical standpoints because they will mechanistically dissect novel therapeutic targets for personalized treatment of NF1-deficient tumors such as plexiform neurofibromas.

Narrative: Read about the project’s background, goals, specific aims, and impact (auspices of Dr. D. Wade Clapp,

Preclinical Testing in Neurofibromatosis

 Springer-and-Ratner-for-NTAP-for-webNancy Ratner, Ph.D., (Cincinnati Children’s Hospital)

The overall goals of this research are to : 1) Establish the durability of the effect of the combination of BRD4i + MEKi and also identify potential biomarkers, and 2) to determine whether EZH2 inhibition is an effective therapeutic approach.  The studies are highly significant because they will establish the durability of the BRD4/MEK combination enabling its advancement to the clinic, and help establish another target (EZH2) as a viable therapeutic approach.

Narrative: Read about the project’s background, goals, specific aims, and impact (auspices of Dr. Nancy Ratner,

Can targeted therapy prevent neurofibroma growth in mice

 Springer-and-Ratner-for-NTAP-for-webNancy Ratner, Ph.D. (Cincinnati Children’s Hospital)

Dr. Ratner and her team hypothesize that Stat3 inhibition using a Stat3 Antisense RNA will prevent tumor formation.  Already, the  inhibitor, AZD 9150 / ISIS 481464 has shown efficacy in multiple myeloma and is in Phase1/1b trials in other cancers. This project will identify methods to prevent neurofibroma formation.  The impact of this project could allow for the rapid translation of early intervention to human patients.

Narrative: Read about the project’s background, goals, specific aims, methods, results and impact (auspices of Dr. Nancy Ratner,

A Nerve Sheath Tumor Bank from Patients with NF1

David-Loeb3-for-webDavid Loeb, M.D., Ph.D. (Johns Hopkins University)

The goals of this project are to establish a biorepository of tissue and serum from NF1 patients with PN and MPNST and  increase accessibility of these tissues to the research community through a collaboration with the CTF tissue repository.  This project will improve access to tissue as a core tool to support discovery of new therapeutics for NF1 patients.

Narrative: Read about the project’s background, goals, specific aims, methods, results and impact (auspices of Dr. David Loeb,

Historical NTAP-funded Open Proposal Projects:

SUZ12 Prevention trial for tumor formation in mice modeling NF1 microdeletion patients

lm_thomas_deraedt-webThomas De Raedt, Ph.D., The Brigham and Women’s Hospital

The main goal of this project was to determine if BRD4 inhibitors can prevent or delay the onset of tumors in a mouse model for MPNST development in NF1 microdeletion patients (NPS mice) and if the treatment with BRD4 inhibitors prevents the recruitment of immune cells to tumor initiation sites.

Narrative: Read about the project’s background, goals, specific aims, results and impact (auspices of Dr. Thomas de Raedt,

Exploring the plexiform neurofibroma interactome

Jkomoruv,kakajan,photoianqiang Wu, M.D., Ph.D. and Kakajan Komurov, Ph.D. (Cincinnati Children’s Hospital)

This project aimed to identify molecular signatures of Schwann cells and non-Schwann cells (macrophages, fibroblasts, mast cells and endothelial cells) to define the neurofibroma interactome and potential therapeutic targets for preclinical and clinical trials.

Narrative: Read about the project’s background, goals, methods, results, and impact (auspices of Dr. Jianqiang,; Dr. Kakajan Komurov,

Publication: Choi K, Komurov K, Fletcher JS, Jousma E, Cancelas JA, Wu J,
Ratner N. An inflammatory gene signature distinguishes neurofibroma Schwann cells and macrophages from cells in the normal peripheral nervous system. Scientific Reports 2017 Mar; 7, 43315. doi:10.1038/srep43315

Regulation of GCPII for the diagnosis and treatment of neurofibromas

Barbara Slusher, Ph.D., M.A.S. (Johns Hopkins University, School of Medicine, Johns Hopkins Drug Discovery Program)

This project aimed to: (1) assess GCPII as a clinical pathologic marker to distinguish benign neurofibromas from malignant MPNSTs; (2) complete GCPII inhibitor pharmacokinetics and pharmacodynamics in Nf1flox/flox; Dhh-Cre mice; (3) evaluate effect of daily administration of a GCPII inhibitor on tumor progression in Nf1flox/flox; Dhh-Cre mice; and (4) assess effect of GCPII genetic knock out on neurofibroma tumor development in Nf1flox/flox; Dhh-Cre mice.

Narrative: Read about the project’s background, goals, specific aims, methods, results, and impact (auspices of Dr. Barbara Slusher,; Dr. Nancy Ratner,; Dr. Anat Stemmer-Rachamimov,

Identification of neurofibroma growth and drug resistance pathways

Nancy Ratner, Ph.D. (Cincinnati Children’s Hospital)

This project aimed to identify molecular pathways that mediate rapid neurofibroma growth and/or response to therapy, using gene expression analysis of mouse neurofibromas followed by validation.

Narrative: Read about the project’s background, goals, specific aims, methods, results, and impact (auspices of Dr. Nancy Ratner,