To characterize the functional roles of MZF1 in NB cells, we applied dCas9-based clustered regularly interspaced short palindromic repeats (CRISPR) 25 to activate or repress expression of MZF1. As shown in Figure 2A, transfection of two independent dCas9a-MZF1 or dCas9i-MZF1 resulted in efficient over-expression or silencing of MZF1 in NB cells, respectively. This evidence concerns the gene MZF1 and neuroblastoma.