Figure 4. MiR-542-3p was the molecular sponge of circ_0000515. (A, B) qRT-PCR assay exposed miR-542-3p expression in BC tissues and cell lines. (C) The correlation analysis of miR-542-3p and circ_0000515 expression in BC tissue. (D) StarBase database predicted the complementary binding site between circ_0000515 sequence and miR-542-3p. (E) Luciferase reporter gene assay confirmed that miR-542-3p and circ_0000515 could interact with each other. (F) miR-542-3p expressions in BC cell lines transfected with circ_0000515 siRNA were under the detection of qRT-PCR. *P<0.05, **P<0.01 and ***P<0.001.