These two PROTACs were conjugated with ALK inhibitors (ceritinib and TAE684) and pomalidomide by different lengths of polyethylene glycol (PEG) likers (Fig. 6).122 These PROTACs induced the potent knockdown of ALK in NSCLC cells H3122 (EML4-ALK), ALCL cells Karpas 299 (NPM-ALK), ALCL cells SU-DHL-1 (NPM-ALK) and NB cells (F1174L/R1275Q ALK), which sustained the ALK downstream signaling inhibition at the same time. This evidence concerns the gene ALK and neuroblastoma.