Delivering circBNC2, decreased cell G2/M arrest frequency as evidenced by decreased p-H3 stained cell numbers and reduced ratios of cyclin B1/cyclin D1 (Supplementary Fig. 6d–g), decreased expression of Tgfb1 and Ctgf (Supplementary Fig. 6h), attenuated ECM accumulation (Supplementary Fig. 6i, j), attenuated ECM accumulation, ameliorated renal fibrosis (Supplementary Fig. 6k, l), and improved renal function, as compared to that in aristolochic acid nephropathy mice treated with AAV9-Vector. The gene discussed is TGFB1; the disease is Balkan nephropathy.