Fig. 4

IGF-1 signalling in keratinocytes and its association to miR-625-3p. A Prediction of target gene and gene function using three miRNA databases (miRDB/TargetScan/miRTarBase). The overlapping predicted target genes from each database were subjected to GO term and KEGG pathway enrichment analysis. B The expression efficiency of miR-625-3p mimic validated using qRT-PCR analysis by HaCaT cells transfection with negative control mimics or miR-625-3p mimics. HaCaT cells were cultured for 48 h after transfection. C qRT- PCR results of insulin growth factor -1 receptor (IGF1R) and IGF-binding proteins gene expression. D IGFBP1 and IGFBP3 level quantified by western blotting 48 h after transfection. E Putative miR-625-3p binding sites in the 3’-UTR of human IGFBP3 mRNA. F Western blot analysis of the phospho-Akt protein level. G qRT-PCR results of Ki67 gene expression. H Cell viability of HaCaT cells transfected with negative control or miR-625-3p-mimic cultured for 24, 48, and 72 h determined using CCK analysis. Data are representative of two independent experiments and values are expressed in means ± SEM. Horizontal lines above bars indicate statistical comparisons with statistical differences between categories. Statistical analyses were performed by the unpaired Student's t-test (B–D, F and G) and 2-way ANOVA (H). *P < 0.05, **P < 0.01, ****P < 0.001 and ****P < 0.0001