Circular RNA circ_0004507 contributes to laryngeal cancer progression and cisplatin resistance by sponging miR-873 to upregulate multidrug resistance 1 and multidrug resistance protein 1.

BACKGROUND Circular RNAs (circRNAs) play critical roles in various types of cancer and chemosensitivity. METHODS The expression levels of circ_0004507 and microRNA-873 (miR-873) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between circ_0004507 and miR-873 was predicted by circinteractome and verified by dual-luciferase reporter assay and RNA pull-down assay. Xenograft tumor model was established to confirm the biological role of circ_0004507 in vivo. RESULTS circ_0004507 was highly expressed and miR-873 was lowly expressed in laryngeal cancer tissues. circ_0004507 knockdown or miR-873 overexpression inhibited cell proliferation, migration and invasion, and increased apoptosis and cisplatin sensitivity in laryngeal cancer cells. miR-873 was identified as a direct target of circ_0004507. circ_0004507 interference inhibited tumor growth and promoted cisplatin sensitivity by upregulating miR-873 in vivo. CONCLUSION Knockdown of circ_0004507 inhibited laryngeal cancer progression and cisplatin resistance by sponging miR-873, providing a potential target for laryngeal cancer therapy.