LIN28A is an RNA-binding protein that regulates developmental timing, pluripotency, and metabolism through two primary mechanisms. First, it suppresses let-7 microRNA biogenesis by binding pre-miRNA terminal loops containing a 5'-GGAG-3' motif and recruiting TUT4/TUT7 uridylyltransferases, causing uridylation and degradation of precursor miRNAs 1. Second, it functions as a translational enhancer, driving specific mRNAs including IGF2 and metabolic enzymes to polysomes and increasing protein synthesis efficiency 2. LIN28A is essential for skeletal muscle differentiation through IGF2 upregulation and maintains pluripotency in embryonic stem cells by preventing let-7-mediated differentiation 3. Clinically, LIN28A is aberrantly upregulated in multiple human cancers, contributing to cancer stem cell generation, epithelial-mesenchymal transition, and metabolic reprogramming 4. The LIN28A/let-7 regulatory loop promotes cellular proliferation, drug resistance, metastasis, and angiogenesis 5. The LIN28A rs34787247 G>A polymorphism increases cancer susceptibility in the Chinese population 6. Notably, LIN28A is a specific marker of pluripotent stem cell-derived extracellular vesicles, supporting their clinical translation for degenerative diseases 7. Emerging therapeutic strategies employ miRNA-based PROTACs targeting LIN28A degradation to restore let-7 expression and enhance chemotherapy sensitivity in breast cancer 8.