RESUMEN
microRNA-21(miR-21) is an endogenous non-coding RNA and plays a key regulatory role in the process of cell proliferation and differentiation. In recent years, miR-21, as a widely studied miRNA, has attracted much attention for its role in skin- related diseases and wound healing. The study shows that miR-21, as a " broad factor", affects the proliferation, apoptosis, migration and invasion of different cells (keratinocytes, T cells, fibroblasts, etc.) by inhibiting the transcription and translation of different target genes (PTEN, TIMP, PDCD4, etc.) . At the same time, it plays a crucial role in skin tumors, skin immune diseases, skin inflammatory diseases, skin wounds and scar tissue formation by promoting inflammation through different signaling pathways. In this study, we reviewed the regulatory roles of miR-21 in different skin diseases (melanoma, cutaneous squamous cell carcinoma, T-cell lymphoma, psoriasis, scleroderma, etc.) and wound healing, aiming at deepening the understanding of miR-21 molecule in skin-related diseases and wound healing. The potential of miR-21 as a biomarker for skin disease diagnosis and its ability to evaluate the efficacy of drugs were also discussed. miR-21 is expected to become a new target of skin disease and wound healing, which may provide a new direction for clinical research.