Figure 4. Screening and identification of upregulated miRNAs in Nor-Exo and IGF-Exo. (A) Heat map showing the 6 miRNAs for which expression was upregulated ≥ 2-fold in IGF-Exo compared to Nor-Exo. (B) IGF-1-induced miRNA regulation network. (C) Among the 6 upregulated miRNAs, miR-219a-2-3p expression increased the most. (D) qRT-PCR comparison of rno-miR-219a-2-3p, 138-5p, 92b-3p, 92b, 25-5p, and 674-3p expression between Nor-Exo and IGF-Exo from 3 independent experiments. *P < 0.05, **P < 0.01 for IGF-Exo vs. Nor-Exo.