MicroRNA-17-3p promotes keratinocyte cells growth and metastasis via targeting MYOT and regulating Notch1/NF-κB pathways.

Wound healing is a fundamental biological process to restore skin integrity. The role of microRNAs (miRNAs) during this process remains elusive. Thus, our study aimed to investigate the biological functions and its molecular mechanisms of miR-17-3p in cutaneous wound healing. Human keratinocyte cell line HaCaT was transfected with miR-17-3p mimic, antisense oligonucleotides (ASO)-miR-17-3p and corresponding controls respectively. After transfection, MTT, flow cytometry, qRT-PCR and western blot were performed to analyze cell viability, colony-formation and cell cycle. Next, scratch wound, Transwell and western blot were used to examine cell migration ability. Besides, prediction of miR-17-3p target was performed by TargetScan and microRNA database, dual-luciferase reporter assay, qRT-PCR and western blot. Moreover, the functions of the MYOT on cell proliferation and metastasis were detected by transfection with its expression vector. Signal pathways of Notch1 and NF-κB were performed by qRT-PCR and western blot. Results showed that miR-17-3p overexpression distinctly promoted cell viability, colony formation, arrested cells at G2/M phase, and upregulated cyclin D1, cyclin B1 and CDK2. Simultaneously, miR-17-3p overexpression increased cell migration and downregulated E-cadherin but upregulated vimentin and α-SMA expression. Moreover, MYOT was verified as a target of miR-17-3p, and it remarkably inhibited HaCaT cells proliferation and metastasis. Protein expression levels of cyclin D1, cyclin B1, CDK2, vimentin and α-SMA were downregulated while E-cadherin was upregulated by MYOT. Furthermore, miR-17-3p signally activated Notch1/NF-κB pathways. These data demonstrated that miR-17-3p promoted keratinocyte cells proliferation and metastasis via targeting MYOT and activating Notch1/NF-κB signal pathways in cutaneous wound healing.