ALK and neuroblastoma: Small-molecule inhibitors of PTPRZ1 have been proposed as suitable therapeutic alternatives for glioblastoma and central nervous system disorders (Fujikawa et al., 2016; Fujikawa et al., 2017; Pastor et al., 2018), and pharmacological inhibition of PTPRZ1 resulted in increased ALK and TrkA phosphorylation in SH-SY5Y neuroblastoma cells (Fernández-Calle et al., 2018).