Fig. 2

Sulfarotene potentially targets RARα in HCC TRCs. a RNA-Seq analysis revealed that RARα mRNA expression was upregulated in HCC TRCs after sulfarotene treatment compared to that of RARβ and RARγ. b Upregulation of RARα mRNA expression in HCC TRCs after sulfarotene treatment. Hep3B-TRCs and PLC/PRF/5-TRCs were treated with sulfarotene at 1.0 and 5.0 µM compared to DMSO control for 48 h. The expression levels of RARα relative to the control were normalized to GAPDH (n = 3). c Increase of RARα protein levels in Hep3B-TRCs and PLC/PRF/5-TRCs in response to dose-dependent sulfarotene treatment as revealed by western blotting. GAPDH served as the internal reference. d Effects of sulfarotene and an RARα antagonist on colony spheroid formation from TRCs. Tukey’s post hoc test. e Effects of sulfarotene and RARα antagonist on the migration and invasion abilities of TRCs. Tukey’s post hoc test. f Representative images of RARα (red) immunofluorescence intensity in Hep3B-TRCs and PLC/PRF/5-TRCs 48 h after treatment with sulfarotene at 1.0 and 5.0 µM. DAPI was used to counter-stain the nucleus with blue fluorescence. g Activation of RARα by sulfarotene as assessed by nuclear translocation. The cytosolic and nuclear fractions Hep3B-TRCs and PLC/PRF/5-TRCs after sulfarotene treatment for 48 h were isolated by ultracentrifugation. The RARα protein level in each fraction was analyzed by western blotting. Data are the mean ± SD of 3 independent experiments; *P < 0.05, **P < 0.01, ***P < 0.001