Total RNA or processed RNA was isolated using miRNeasy Mini Kit following the manufacturer's instructions. For regular cDNA synthesis, reverse transcription (RT) was performed in a 20-μl reaction containing RNA, 1 × RT buffer, 0.5 mM of each dNTP, 150 ng of random hexamers (11034731001, Roche) and maxima reverse transcriptase (RT) (EP0741, Thermo Fisher Scientific), and incubated at 25°C for 10 min followed by 30 min at 50°C; the RT enzyme was inactivated by heating at 85°C for 5 min (25 (link)). For qPCR analysis of circRNAs and mRNAs, 20-μl PCR reactions were set up with 0.1 μl of cDNA, 1 × KAPA SYBR® FAST qPCR mix (ABI Prism) (KK4605, KAPA Biosystems), and 250 nM gene-specific primers. The RT and PCR reactions were performed on Veriti® 96-Well Thermal Cycler (#4375786, Thermo Fisher Scientific, USA). QuantStudio 5 Real-Time PCR System (Thermo Fisher Scientific) with a cycle setup of 2 min at 95°C and 40 cycles of 2 s at 95°C plus 10 s at 60°C was used for RT-qPCR followed by calculation of the RNA fold change using the 2−ΔΔCT method (26 (link)).