RT-qPCR

Trizol (Invitrogen) was applied for total RNA extraction. In short, RNAs were transcribed into cDNA in reverse via PrimeScript™ RT reagent Kit (Takara, China). Then, qPCR was performed with Bestar®SybrGreen qPCR mastermix (DBI). Relative gene expressions were determined by 2^−ΔΔCt method, with circPUM1, JUNB and miR-30a-5p expression respectively normalized to GAPDH or U6 [^15–18]. The primer sequences applied were as listed below: circPUM1 Forward: 5′-GATTATTCAGGCACGCAGGT-3′, Reverse: 5′-CCCTCCTCCTTCAAATCTCC-3′; JUNB Forward: 5′-GACACAGGCGCATCTCTGAAG-3ʹ,Reverse: 5′-GATCACGCCGTTGCTGTTG-3ʹ; GAPDH Forward: 5′-GCACCGTCAAGGCTGAGAAC-3′, Reverse: 5′-ATGGTGGTGAAGACGCCAGT-3ʹ; miR-30a-5p Forward: CGCGATGTTGAAACATCCTCGAC-3ʹ, Reverse: 5ʹ-ATCCAGTGCAGGGTCCGAGG-3ʹ; U6 Forward: 5′-CCTGCGCAAGGATGAC-3′, Reverse: 5′- -GCTTCGGCAGCACATATACTAAAAT-3′.