RT-qPCR was conducted using TaqMan® MicroRNA RT Kit (Applied Biosystems; Thermo Fisher Scientific, Inc.). miR-24 was used as an internal control [stem-loop RT primer sequence: 5'-GTCGTATCCAGTGCAGGGTCCGAGGTATTCGCACTGGATACGACCTTCTG-3', forward primer: 5'-GCGGCGGTGGCTCAGTACAGC-3' for miR-24, and (universal) reverse primer: 5'-GTGCAGGGTCCGAGGT-3'] during the quantification using specific stem-loop primers for miR-15b (stem-loop RT primer sequence: 5'-GTCGTATCCAGTGCGTGTCGTGGAGTCGGCAATTGCACTGGATACGACTGTAAACC-3'; forward primer: 5'-ATCCAGTGCGTGTCGTG-3', and reverse primer: 5'-TGCTTAGCAGCACATCATG-3') to normalize it as follows: ∆Ct=∆CtmiR-∆CtmiR-24(24 (link)). The analysis of the results was performed using Sequence Detection Software version 2.3 (Applied Biosystems; Thermo Fisher Scientific, Inc.). The difference in the miR-15b relative expression levels between samples was calculated using the 2-ΔΔCq method (25 (link)).