miRNAbased

miRNAbased refers to approaches, technologies, and research focused on microRNAs (miRNAs) and their regulatory roles, with particular emphasis on therapeutic and diagnostic applications. It encompasses the use of miRNA mimics to restore the activity of tumor-suppressive miRNAs, inhibitors (antagomirs or anti-miRs) to shut down oncogenic miRNAs, and more complex modalities such as miRNA sponges and gene-therapy–based delivery systems. In diagnostics, miRNA expression profiles serve as biomarkers for tissue origin, disease state, and prognosis.

MicroRNAs are small noncoding RNAs, about 22 nucleotides long, that regulate gene expression post-transcriptionally by guiding the RNA-induced silencing complex (RISC) to target mRNAs. They are transcribed as primary miRNAs, processed by Drosha into precursor miRNAs, exported to the cytoplasm, and diced by Dicer to produce mature miRNA duplexes. One strand becomes the guide RNA to RISC, inhibiting translation or triggering mRNA degradation.

Therapeutic modulation relies on delivery systems such as lipid nanoparticles, conjugates (e.g., GalNAc for liver targeting), and chemical modifications that improve stability and specificity. Challenges include off-target effects, immune activation, delivery efficiency, and variable expression across tissues.

Clinically, anti-miR-122 Miravirsen showed proof of concept for hepatitis C as a proof-of-principle; the miR-34a mimic MRX34 entered cancer trials but was halted due to safety concerns. miRNAbased therapies hold potential across oncology, liver disease, cardiovascular disorders, and viral infections, but require further optimization and careful safety assessment.