Fig. 1

CircPLK1 expression was enhanced in BC tissues and cells. a The expression of circPLK1 was detected by qRT-PCR in 35 pairs of BC tissues and adjacent normal tissues. b ΔΔct is the difference between the ΔCT of BC tissues and the ΔCT of adjacent normal tissues. Relative circPLK1 expression in BC tissues (n = 35) compared with corresponding non-tumor tissues (n = 35). Positive − ΔΔct meant high circPLK1 expression. Negative − ΔΔct meant low circPLK1 expression. c CircPLK1 expression was determined by qRT-PCR in BC cells (BT549 and HCC38) and MCF-10A cells. d The relative levels of circPLK1 and PLK1 mRNA were measured after treatment with RNase R by qRT-PCR. e Relative RNA levels of circPLK1 and PLK1 mRNA were detected after reverse transcription with random primers and Oligo (dT) 18 primers by qRT-PCR. ***P < 0.001