Fig. 1.

Circular RNA circCCDC85A is downregulated in breast cancer. A The existence of circCCDC85A was validated in two breast cancer cells and two cases of breast cancer tissues by RT-PCR. Divergent primers amplified circular RNA transcript circCCDC85A in cDNA but not gDNA. While convergent primers amplified linear RNA transcript CCDC85A in both cDNA and gDNA. GAPDH was used as an internal reference. B Sanger sequencing result of the above RT-PCR product indicated the junction sequence of circCCDC85A. C The expression level of circCCDC85A and the linear CCDC85A were detected by qRT-PCR in MCF-7 cells with RNase R treatment. D The relative expression level of circCCDC85A in cytoplasm and nuclear by qRT-PCR after fractionation of nuclear and cytoplasmic RNA in MDA-MB-231 and MCF-7 cells. E FISH assay showed that circCCDC85A preferentially localized in the cytoplasm of MDA-MB-231 and MCF-7 cells. F The percentage of circCCDC85A expression in 58 breast cancer tissues and 40 normal breast tissues. **P < 0.01