Figure 5. ALK contributes to cell migration and invasion.

(a) Overexpression of ALK enhanced NBL cell migration and invasion. SK-N-AS cells were transfected with pcDNA3-ALK or empty plasmid, and ALK ectopic expression (220 kDa) was determined by immunoblotting (left, full-length blots are presented in Supplementary Figure S9). Migration assays (middle) and invasion assays (right) were performed in Boyden chambers. (b) siRNA-mediated knockdown of ALK suppressed NBL cell migration and invasion. NBL-S cells were transfected with control siRNA or siRNA targeting ALK. Knockdown of ALK mRNA expression in NBL-S cells was confirmed by qRT-PCR (left). Migration assays (middle) and invasion assays (right) were performed as (a). All experiments were performed in triplicate.