Fig. 1

Expression of circRNA_15430 is low in GC cell lines and tissues. A GEO dataset (GSE100170, GSE152309, GSE163416 and GSE131414) were downloaded for analyzing abnormal expression of circRNAs in GC tissues. B Schematic illustration of the formation of circRNA_15430 via the circularization of exons in the abl2 gene. PCR product sequencing conformed to the head-to-tail splicing of circRNA_15430. C Gel electrophoresis validated the existence of the back-spliced and canonical forms of abl2 in the presence or absence of RNase R enzyme supplementation in cDNA and gDNA from GC cells. D qRT-PCR detected circRNA_15430 expression in GES-1 cells and three GC cell lines. E qRT-PCR detected relative circRNA_15430 level in 42 paired fresh normal gastric tissues and GC tissues. F and G The correlation between OS and PFS with circRNA_15430 expression in GC patients. H and I Nuclear-cytoplasmic fractionation and RNA FISH assay found that circRNA_15430 is located both in the cytoplasm and nucleus of GC cells (scale bars = 25 μm). *P < 0.05, **P < 0.01