Retinoic acid-free spheroid culture condition is suitable for growth of TH-MYCN neuroblasts. Mus musculus

It has been already reported that there are undifferentiated/proliferating neuroblasts in the postnatal sympathetic ganglia in TH-MYCN mice. Given the fact that neuroblastoma is derived from sympathoadrenal progenitors which are originated from neural crest stem cells, we attempted to use the well-established culture condition that has been utilized to maintain derivatives of neural crest stem cells. However, the medium contained retinoic acid (RA) which is known to induce neuroblastoma differentiation and is used in clinical treatment against high-risk patients. In the present study, the medium with RA (RA (+) medium) and without RA (RA (-) medium) were compared. Since undifferentiated neuroblasts are observable at one of the sympathetic ganglia, superior mesenteric ganglion (SMG), in 3-week-old TH-MYCN hemizygote (TH-MYCN+/-) mice with 129+Ter/SvJcl mice background, we dissected and dissociated the SMG to prepare single cells. These cells were cultured in either RA (+) or RA (-) media. Spheres formed in either RA (+) or RA (-) medium were subjected to microarray analysis. Overall design: Dissociated single cells from a 3-week-old TH-MYCN (hemizygote) SMG were divided into RA (+) and RA (-) medium. Formed primary spheres were subjected to micorarray analyis. RA (+) and RA (-) spheref from four individual biological replicates were analyzed.