Fig. 7

Kartogenin and retinoic acid cooperate to reduce the viability of MYCN-amplified neuroblastoma cells. a Imaging of IMR32 cells treated for 3 days singly with 1 μM RA or 10 μM KGN, or a combination of both. All panels are imaged at 40× magnification. b The differentiation ratio of IMR32 cells treated for 3 days with individual agents (KGN or RA) or combination treatments (KGN and RA). The images from three biological replicates were pooled and then measurements of individual cells were made using ImageJ v1.44p (http://imagej.nih.gov/ij). The range of measured cells (N) per treatment group is 177–352. The differentiation ratio of each cell was calculated by dividing the length of its longest axon by the cell’s width. All treatment groups are significantly different (with a p value <0.0001) to the untreated control cells. c, d Cell viability analysis of MYCN-amplified IMR32 (c) or single-copy MYCN parental SY5Y (d) cells treated for 72 h with KGN and RA, either individually or in combination, as detected by MTS assay. Viability is set relative to that of the respective control untreated cells (IMR32 or SY5Y), with error bars denoting the standard deviation between replicates. e Cell viability analysis of un-induced SY5Y-MYCN cells treated for 72 h with the TGF-βR1 inhibitor RepSox, as detected by MTS assay. Viability is set relative to that of the respective DMSO vehicle-control cells, with error bars denoting the standard deviation between replicates. f The differentiation ratio of un-induced (no Dox) SY5Y-MYCN cells treated for 3 days with RA-only or RA and RepSox combination treatment. The images from three biological replicates were pooled and then measurements of individual cells were made using ImageJ v1.44p (http://imagej.nih.gov/ij). The range of measured cells (N) per treatment group is 135–151. The differentiation ratio of each cell was calculated by dividing the length of its longest axon by the cell’s width. P values (t-test) of each treatment group compared with the DMSO-vehicle controls are shown above each box