Welcome to the second in a series of “NF Bites” – providing snapshots of individual areas of neurofibromatosis research and how the Children’s Tumor Foundation is advancing this. Over the coming days and weeks we will focus on different aspects of NF1 and NF2 research. Today: where are we with NF1 plexiform neurofibroma research progress?
The Children’s Tumor Foundation is currently investing in both traditional and highly novel approaches to developing drug treatments for NF1 plexiform neurofibromas. These are the most common tumor type seen in NF1, and can cause devastating health issues. However researchers now have a reasonable understanding of their biology and are applying this information in developing clinical treatments; and plexiform tumors have been the first NF1 tumor type to advance into a number of ongoing clinical trials.
· Bruce Korf (University of Alabama at Birmingham) was, in 2009, a recipient of one of our first $125,000 Clinical Trial Awards to assess, in collaboration with Aerang Kim and Brigitte Widemann (National Cancer Institute) the drug Sorafenib in a pediatric plexiform tumor clinical trial.
· Through the Foundation’s NF Preclinical Consortium, a $4M multi-year initiative to accelerate the most promising candidate drugs to the clinic, the laboratories of Tim Cripe and Nancy Ratner (Cincinnati Children’s Hospital Medical School) are assessing a pipeline of candidate plexiform neurofibroma drugs. The Consortium includes collaborations with Novartis, Genentech, Pfizer and Avila Therapeutics.
· In a cutting edge approach, Foundation Drug Discovery Initiative Awardee Jonathan Chernoff (Fox Chase Cancer Center) is endeavoring to normalize mast cell signaling in plexiform tumors, as abnormal signaling is believed to promote tumor growth. To do this Dr. Chernoff will develop induced pluripotent stem cells (iPS) – a form of adult stem cells – from mouse skin, and transplant these transplanted into the NF1 mouse bone marrow – the cells should differentiate into normal mast cells which then migrate to the tumor and halt its growth.
· Young Investigator Awardee Huarui Zheng (University of Michigan) is also targeting mast cells in mouse models plexiform neurofibromas, this time using targeted drug treatments. Margaret Wallace (University of Florida) has received two Drug Discovery Initiative Awards in the past year for drug testing on plexiform neurofibromas. One Award tests PTC Therapeutics VEGF-blocking drug PTC-299 (now in clinical trials at Massachusetts General Hospital for NF2), while the other Award tests indoprofen derivative drugs, which target nonsense mutations in the gene to correct neurofibromin protein production.
· Outside of Foundation funding, other plexiform neurofibroma clinical trials of note are currently under way. These include: CDMRP NFRP Phase II Clinical Trials Consortium is conducting a trial of Rapamycin in plexiform neurofibroma; Children’s Hospital of Philadelphia has initiated a Phase I (safety) trial of photodynamic therapy for these tumors; and Indiana University has pioneered the use of imatinib mesylate (Gleevec) to treat these tumors.
Look for more NF Bites in the coming days and weeks!
