Fig. 1

Characterization of circ0001955 in CSCC. A The genomic loci of the circ0001955 gene. Circ0001955 is synthesized at the CSNK1G1 gene locus containing exons 11 to 16. The back-splice junction of circ0001955 was identified by Sanger sequencing. B PCR analysis for circ0001955 and its linear isoform CSNK1G1 in cDNA and genomic DNA (gDNA). C qRT-PCR analysis for the expression of circ0001955 and CSNK1G1 mRNA after treatment with RNase R in SiHa cells. D Cytoplasmic and nuclear mRNA fractionation experiments show that circ0001955 is localized mainly in the cytoplasm of SiHa cells. GAPDH was applied as a positive control in the cytoplasm. E RNA fluorescence in situ hybridization for circ0001955 in SiHa cells; the junction probe was complementary to the back-splice junction sequence of circ0001955. Nuclei were stained with DAPI. Scale bar, 50 μm. F and G Expression levels of circ0001955 in CSCC tissues in comparison with matched normal tissues were measured using qRT-PCR. H Diagnostic value of circ0001955 for CSCC was evaluated by ROC curve. Each experiment was performed at least three times independently. ****P < 0.0001