In molecular biology miR-181 microRNA precursor is a small non-coding RNA molecule. MicroRNAs (miRNAs) are transcribed as ~70 nucleotide precursors and subsequently processed by the RNase-III type enzyme Dicer to give a ~22 nucleotide mature product. In this case the mature sequence comes from the 5' arm of the precursor. They target and modulate protein expression by inhibiting translation and / or inducing degradation of target messenger RNAs. This new class of genes has recently been shown to play a central role in malignant transformation. miRNA are downregulated in many tumors and thus appear to function as tumor suppressor genes. The mature products miR-181a, miR-181b, miR-181c or miR-181d are thought to have regulatory roles at transcriptional level, through complementarity to target mRNAs. miR-181 which has been predicted or experimentally confirmed in a wide number of vertebrate species as rat, zebrafish, and in the pufferfish (MIPF0000007).
miR-181 is functionally critical in the maintenance of EpCAMAFP HCC cells, possibly by inhibiting hepatic cell differentiation and promoting HCC stemness through targeting the transcriptional regulators caudal type homeobox transcription factor 2 (CDX2), GATA binding protein 6 (GATA6), and the Wnt signaling inhibitor nemo-like kinase (NLK).