To further characterize the relationship between the KDM3B modulatory effect and gene expression changes related to the APL differentiation process, the differential gene expression patterns of KDM3B-knockdown NB4 cells were compared against those of the scrambled control cells in the presence of ATRA, and the differentiated control NB4 cells were compared with the undifferentiated NB4 cells, as schematically depicted in Fig. 4a (Additional files 3, 4). This evidence concerns the gene KDM3B and acute promyelocytic leukemia.