Puerarin Inhibits the Progression of Bladder Cancer by Regulating circ_0020394/miR-328-3p/NRBP1 Axis.

Previous studies have shown puerarin to be a potential therapeutic drug for treatment of bladder cancer. But the role and possible molecular mechanism of puerarin remain unknown. Cell viability, apoptosis, migration, and invasion were assessed by Cell Counting Kit-8 (CCK-8), flow cytometry, and transwell assays, respectively. Western blot was used to measure the levels of all protein. Glucose consumption and lactate production were detected using a glucose and lactate assay kit. Circular RNA_0020394 (circ_0020394), microRNA-328-3p (miR-328-3p), and nuclear receptor binding protein 1 (NRBP1) levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miRNA and circRNA or mRNA was confirmed using dual-luciferase reporter assay. experiments were performed to examine the effect of puerarin on tumor growth. Puerarin suppressed cell viability, migration, invasion, and glycolysis, and induced apoptosis in bladder cancer. circ_0020394 was downregulated in puerarin-treated bladder cancer cells, and circ_0020394 overexpression attenuated the inhibitory effect of puerarin on cell progression. Moreover, circ_0020394 could bind to miR-328-3p, and miR-328-3p directly targeted NRBP1. Functionally, miR-328-3p could reverse the promotion effect of circ_0020394 overexpression on the progression of puerarin-treated cells, and silencing NRBP1 counteracted the effects of anti-miR-328-3p on puerarin-treated cells. Mechanically, circ_0020394 could increase NRBP1 expression by acting as miR-328-3p sponge in puerarin-treated bladder cancer cells. Besides, puerarin inhibited tumorigenesis by increasing miR-328-3p and decreasing the levels of circ_0020394 and NRBP1. Puerarin impedes cell viability, migration, invasion, and glycolysis, and promoted apoptosis in bladder cancer by regulating circ_0020394/miR-328-3p/NRBP1 axis.