Fig. 1

Hsa_circ_0000520 is highly expressed in cervical cancer. A Heatmap displaying the expression of top 20 differentially expressed circRNAs in the microarray dataset GSE102686. B Expression of hsa_circ_0000520 determined in clinical cervical cancer tissues (n = 52) by RT-qPCR. C Resistance of hsa_circ_0000520 to RNase R digestion verified by RNase R linear RNA digestion experiment with RT-qPCR. D Content of hsa_circ_0000520 in nuclei normalized to U6 (nuclear control transcript), and cytoplasm normalized to GAPDH (cytoplasmic control transcript) measured by nuclear-cytoplasm isolation assay. E Subcellular localization of hsa_circ_0000520 by FISH assay. F Expression of hsa_circ_0000520 in different cervical cancer cell lines and in the nucleus after nuclear-cytoplasm isolation assay. G Silencing efficiency of sh1-hsa_circ_0000520 and sh2-hsa_circ_0000520 determined by RT-qPCR. H Number of cell clones in each group. I Images of cell proliferation by EdU assay. J Percentage of proliferation. K Effects of hsa_circ_0000520 on proliferation of cells determined using CCK-8 assay. *p < 0.05 vs. adjacent normal tissues, RPPHI, cytoplasm, SiHa cells or cells in the sh-NC group. Measurement data are presented as mean ± standard deviation derived from at least 3 independent experiments. Cancerous tissues are compared with adjacent normal tissues using paired t-test. Data from two unpaired groups are compared by independent sample t test. Data from multiple groups are compared by one-way ANOVA followed by Tukey’s test. Data at different time points are compared by repeated measures ANOVA followed by Bonferroni’s test