Oncolytic virotherapy for neuroblastoma.

Metastatic neuroblastoma (NB) remains a clinical challenge for pediatric oncologists. Overall survival rates stay less than 40% despite intensive multimodal therapy, with the toll of toxicity being related to high-dose chemotherapy. These rates have shown minor improvements over the last years, and the development of newer therapeutic strategies is necessary. Oncolytic viruses bear the promise of killing cancer cells with low toxicities to healthy tissues. Acting through mechanisms different from chemo- and radiotherapies, a growing arsenal of genetically engineered viruses is being tested in preclinical models of human cancers. Viral infection and selective replication inside tumor cells are achieved by modification of the virus genome in order to target specific molecules or signal transduction pathways of cancer. Cell death may also activate antitumor immune responses to further amplify the beneficial effects. Clinical trials in humans have been conducted and initial results have been reported, giving the first glance of information on safety and efficacy in patients. In this review we will summarize information about how oncolytic virotherapy is being evaluated against NB in preclinical models and recent reports on the use of this new therapy in sporadic cases of children with refractory NB.