Here, we assessed the expressions of six circRNAs that have been reported to be abnormally expressed in breast cancer: circ_0108942, circ_0001785, circ-ERBB2, circ-BMPR2, circ-UBE2D2, circ-IRAK3 [10, 11, 26–28]. This evidence concerns the gene UBE2D2 and breast cancer.