Fig. 1

circFOXP1 is upregulated in GBC tissues. a The heat map showed that the upregulated 44 circRNAs and downregulated 81 circRNAs in GBC tissues when compared with adjacent non tumor tissues analyzed by RNA sequencing. The 34 of the upregulated 44 circRNAs were overlapped in database obtained from circBase. b Top, circFOXP1 expression levels were evaluated with qRT-PCR in tissues from 40 cases of GBC compared with adjacent normal tissues. The expression of circFOXP1 was normalized to GADPH. Significant differences between groups were analyzed with a paired samples t-test, ***P < 0.001. Low, Kaplan-Meier analysis and log-rank tests were performed to analyze the association between the expression of circFOXP1 and OS time of GBC patients. CircFOXP1 expression levels were classified as higher expression (circFOXP1 expression rate > median expression rate) and lower expression (circFOXP1 expression rate < median expression rate). c RNAs were isolated from five GBC cell lines and the H69 cell line and subjected to a northern blot analysis using a probe specific for circFOXP1 (top). Arrow, circFOXP1 expression was shown. d Standard PCR was performed to detect the circFOXP1 from control RNA or digested RNAs using RNase R exonuclease in five GBC cell lines. Arrow, circFOXP1 expression was shown. e RNA fluorescence in situ hybridization (FISH) was performed for circFOXP1. Nuclei were stained with 4, 6-diamidino-2-phenylindole (DAPI); the original magnification was 400×