Fig. 5: A circular RNA derived from the ARID1A gene drives proliferation and survival of neuroblastoma cells.

a Comparison of circRNA expression in neuroblastoma samples (green, n = 104 biologically independent samples) with published normal brain tissue samples (blue, n = 72 biologically independent samples) and pediatric and adult cancer samples (“various tumors”, brown, n = 86 biologically independent samples). circARID1A is marked in bold and with an asterisk. Data are presented as a box plot. The box plot center line, violin limits and whiskers indicate the median, upper/lower quartiles and 1.5× interquartile range respectively. b Scheme showing the genomic representation of the ARID1A gene and circARID1A. The PCR detection strategy and a trace of sanger sequencing of the back-splice junction of circARID1A is shown (primers are marked by arrows). Exons (Ex) involved in circularization and the back-splice junction (BSJ) are marked. c Direct detection of circARID1A by RNA-FISH with a probe specific for the back-splice junction in IMR-5 cells (red color). Nuclei were stained by DAPI (blue color). Insert was digitally magnified. Scale large image 50 µm, insert 10 µm (n = 2 biologically independent experiments). d Scheme illustrating the strategy for a knockdown of circARID1A by using siRNAs targeting the BSJ. e–i Knockdown of circARID1A with 2 different siRNAs in comparison to a scrambled control in 4 different neuroblastoma cell lines (n = 3 biologically independent experiments, in e–h data are presented as mean ± SD, Two-way ANOVA test). e Expression of circARID1A and ARID1A mRNA as determined by qRT-PCR; f Total cell numbers; g Cell viability; h Annexin V positive cells as determined by flow cytometry; i Measurement of cell proliferation detected in real-time (Data are presented as median ± range). Source data are provided as a Source Data file.