Up-regulation of HOXD-AS1 in SH-SY5Y neuroblastoma cell line by RA and stage correlation in patients. (A) SHSY5Y cells plated onto laminin coated dishes were induced to differentiate with 10 µM retinoic acid (RA). Total RNA was extracted at the time-points of 0 hours (uninduced), 6, 24 and 120 hours. The amounts of the selected 13 probes were quantified by qRT -PCR using relative DDCt quantification method and expressed as a fold change relative to uninduced time-point (0 hours). (B) HOXD-AS1 expression correlates with neuroblastoma progression and differentiates between early (st. 1-2) and late (st. 3-4) stage tumors. Each patient of the whole studied population of 64 patients diagnosed with NB (55) is represented by a dot.