Developing Biomarkers of Plexiform Tumor Burden in Patients With Neurofibromatosis-Type 1

Neurofibromatosis type 1 (NF1) is a common inherited human disorder, with a frequency of approximately 1:2500 worldwide. A hallmark of NF1 is development of plexiform neurofibromas (PNFs) in 30 to 50% of NF1 patients. Currently, there are no biomarkers of tumor burden and whole-body magnetic resonance imaging (MRI) is expensive and limited to few centers. The investigator established an unbiased pipeline to identify candidate biomarker signals of tumor burden using plasma from neurofibroma-bearing DhhCre;Nf1fl/fl mice using untargeted metabolomics. Our preliminary data show that glucosylceramide (GC) is the most significantly deregulated compound in plasma from neurofibroma-bearing DhhCre;Nf1fl/fl mice. The investigator developed a novel targeted mass spectrometry method to accurately quantify multiple elevated GC and lactosylceramide (LC) species. In this proposal, the investigator will combine the clinical infrastructure of the NF1 comprehensive program and advance imaging at Ann \& Robert H. Lurie Children's Hospital of Chicago with the mass spectrometry capabilities at Cincinnati Children's Hospital Medical Center. Taking advantage of our large, well-characterized, Lurie Children's NF1 population, the investigator propose to perform analytical validation studies of candidate GC/LC biomarker signature of tumor burden in plasma from NF1 patients with defined numbers of PNF (tumor burden) by whole body MRI. The potential outcomes of our study are identification of candidate biomarker of tumor burden that contribute to patient risk stratification, and analytical validation of GC/LC biomarker signature (context of use). Collectively, this work represents a synergistic approach for discovery and validation of biomarkers of tumor burden in NF1.