The expression level of pro-proliferative Ki67 and cyclin D1 (CCND1) genes [49, 50], as well as of MYCN and Nestin (controlling neuroblastoma aggressiveness [51, 52]), did not undergo any significant change in cells, independent of either 2D or 3D condition (Fig. 2c). This evidence concerns the gene CCND1 and neuroblastoma.