Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12885-022-09241-9/MediaObjects/12885_2022_9241_Fig1_HTML.png)
Hsa_circ_0000277 was upregulated in ESCC cells and its characteristics as a circRNA. A The back-splicing information of hsa_circ_0000277 and Sanger sequencing in the splice junction. B The detection of hsa_circ_0000277 was administrated exploiting RT-qPCR in ESCC (EC9706 and KYSE30) cells and control HET-1A cells. C, D The levels of hsa_circ_0000277 and its linear form (PDE3B mRNA) were assayed by RT-qPCR in EC9706 and KYSE30 cells treated with actinomycin D. E The RT-qPCR was used for analyzing hsa_circ_0000277 and PDE3B mRNA after RNA was exposed to RNase R. F Expression levels of hsa_circ_0000277, GAPDH and U6 were measured using RT-qPCR in the cytoplasmic or nuclear fraction. *P < 0.05