Fig. 1

circPAPD4 is down-regulated in BC and correlated with favorable prognosis. (A) Diagram of circPAPD4 formation. The back-splicing junction of circPAPD4 was verified by Sanger sequencing. (B) Relative expression of circPAPD4 in MCF-10A and breast cancer cell lines (MCF-7, SKBR3, BT474, BT549, and MDA-MB-468) were examined by RT-qPCR. (C) Relative expression of circPAPD4 and linear PAPD4 in MCF-7 and SKBR3 cells with or without RNase R treatment were examined by RT-qPCR. (D) After treated with Actinomycin D, the half-life period of circPAPD4 and linear PAPD4 in MCF-7 and SKBR3 cells were analyzed by RT-qPCR. (E) The main distribution of circPAPD4 and linear PAPD4 in MCF-7 and SKBR3 cells was measured by RT-qPCR after subcellular fractionation. (F) FISH assay was used to determine the subcellular distribution of circPAPD4 in MCF-7 and SKBR3 cells. Scale bar: 10 μm. (G) circPAPD4 expression levels in 20 pairs BC tissues and paracancerous tissues were measured by RT-qPCR. (H) Representative images of ISH of the high/low expression circPAPD4 in BC tissues. Scale bar: 20 μm. (I) The association between circPAPD4 expression and recurrence rate of BC patients was illustrated using Kaplan-Meier log-rank method. Data are presented as means ± SD. **p<0.01;***p < 0.001.