ALK and neuroblastoma: Interestingly, in biologically relevant NB animal models, we demonstrated that, compared to free ALK-siRNA, Fab′-GD2-CCL(ALK-siRNA) increased siRNA stability, and a selective block of NB tumor growth, resulting in partial tumor regression (Figure 3B), improved silencing of the specific gene (Figure 3C), and increased life span in NB xenografts (Figure 3D) (45).