**Figure 2.** **Carcinogenic role of circ_RPPH1 in BC.** (**A**) qRT-PCR was used to detect the relative expression of circ_RPPH1 in si-circ_RPPH1. (**B**) qRT-PCR was used to detect the relative expression of circ_RPPH1 in BC cells transfected with si-circ_RPPH1#2. (**C**) CCK-8 test was used to detect the proliferation of BC cells transfected with si-circ_RPPH1#2. (**D**, **E**) Transwell test showed the invasion and migration of BC cells transfected with si-circ_RPPH1#2. Scale bars, 50 μm. (**F**, **G**) The changes of cell cycle and apoptosis rate of BC cells transfected with si-circ_RPPH1#2 were detected by flow cytometry. ^{*}indicates *P* < 0.05; ^{**}indicates *P* < 0.01.