Neural differentiation has been carried out using variousproceduresincluding applications of alltrans-retinoic acid (vitamin A derivative),nerve growth factor (NGF), oestradiol, 12-O-tetradecanoylphorbol 13-acetate, cholesterol, and brain-derived neurotrophic factor(BDNF).54 The parameters of 3D bioprintedtumor models including NB cells are shown in Table 2. The gene discussed is BDNF; the disease is neuroblastoma.