The expression levels of relevant mRNAs in HUVECs were measured by qRT-PCR assays. Concretely, total RNA was separated from HUVECs using TRIzol reagent (Invitrogen, Carlsbad, California, USA). NanoDrop-2000c spectrophotometer (Thermo Fisher Scientific, Massachusetts, USA) was used to determine the amount of RNA, and the integrity was determined by 1% agarose modified gel electrophoresis. Then, 1 μg of separated RNA was reverse transcribed into cDNA with the PrimeScript RT Master Mix Perfect Real Time (TaKaRa, Shiga, Japan) according to the manufacturer’s instructions. qRT-PCR assay was conducted using SYBR green qPCR assay (BioRad, USA) on the ABI Prism 7500 Fast Real-time PCR System (Applied Biosystems, Foster City, CA) following the reaction conditions: 30 cycles of hot start at 94℃ for 1 min, denaturation at 94℃ for 1 min, annealing at 50℃ for 45 s, and elongation at 72℃ for 2 min, then final elongation at 72℃ for 8 min. The sequences of primers were showed in Table 1 and synthesized by Gene Pharma (Shanghai, China). GAPDH or U6 served as internal reference, and the data were processed by the comparative 2−ΔΔCt method (15 (link)).