Abstract
<jats:title>Abstract</jats:title> <jats:sec> <jats:label/> <jats:p>MicroRNAs (miRNAs) are small, non‐coding RNA molecules, typically 21–23 nucleotides in length, that regulate gene expression at the posttranscriptional level. Rather than acting on single targets, miRNAs modulate multiple transcripts through partial sequence complementarity, functioning as key regulators of complex gene networks. Through this network‐based activity, they contribute to the fine control of essential biological processes, including development, cellular differentiation, metabolism and immune responses. Not surprisingly, dysregulation of miRNA expression has been consistently associated with a wide range of human diseases, including cancer, cardiovascular and metabolic disorders, neurodegeneration and inflammatory conditions. Over the past decade, advances in understanding miRNA biogenesis, target recognition and context‐dependent activity have highlighted their dynamic and cell‐type‐specific roles in health and disease. These insights have positioned miRNAs as promising therapeutic targets, driving the development of miRNA‐based strategies such as mimics and inhibitors, with continued progress steadily advancing their path toward clinical application.</jats:p> </jats:sec> <jats:sec> <jats:title>Key Concepts</jats:title> <jats:p> <jats:list list-type="bullet"> <jats:list-item> <jats:p>MicroRNAs are small noncoding RNAs that regulate gene expression post-transcriptionally across complex cellular networks.</jats:p> </jats:list-item> <jats:list-item> <jats:p>A single miRNA can recognize multiple targets, dependent primarily on seed‐sequence complementarity and transcript context.</jats:p> </jats:list-item> <jats:list-item> <jats:p>miRNAs function as systems‐level regulators through feedback loops, cooperative subnetworks and target hubs.</jats:p> </jats:list-item> <jats:list-item> <jats:p>Dysregulated miRNAs contribute to all major hallmarks of cancer, including proliferation, metastasis and therapeutic resistance.</jats:p> </jats:list-item> <jats:list-item> <jats:p>Circulating and exosomal miRNAs mediate intercellular communication and serve as potential disease biomarkers.</jats:p> </jats:list-item> <jats:list-item> <jats:p>miRNAs regulate critical pathways involved in cardiovascular disease, diabetes and metabolic dysfunction.</jats:p> </jats:list-item> <jats:list-item> <jats:p>Altered miRNA expression is strongly associated with neurodegenerative diseases such as Parkinson's and Alzheimer's disease.</jats:p> </jats:list-item> <jats:list-item> <jats:p>miRNA mimics and inhibitors represent promising but technically challenging therapeutic strategies.</jats:p> </jats:list-item> </jats:list> </jats:p> </jats:sec>