Mark A. Lemmon, PhD (Damon Runyon Scholar ‘97-‘98, Damon Runyon Fellow ‘93-‘96) of University of Pennsylvania, Philadelphia, and colleagues, reported new findings that will allow physicians to identify which neuroblastoma patients are most likely to respond to crizotinib (Xalkori). The drug was recently approved for treatment of certain lung cancers. It targets a protein called anaplastic lymphoma kinase (ALK) which is mutated in about ten percent of children with deadly neuroblastoma tumors. The researchers reported that these patients respond differently to treatment, depending on the particular mutation in ALK.  The drug blocked growth of neuroblastoma cells with the most common mutation, while tumor cells with a separate ALK mutation were more resistant to the drug. These resistant cells, however, responded to a higher dosage of crizotinib. The researchers are now conducting a clinical trial to determine the appropriate drug dose in children, potentially providing a safer and more effective treatment option than conventional chemotherapy. The study was published in the journal Science Translational Medicine.