Abstract
Liquid biopsy has great application value in the field of precision medicine because of its non-invasiveness, sensitivity and dynamics. Cell-free RNA molecules are one of the emerging biomarkers that can be used for liquid biopsy, and cell-free non-coding RNAs have become main RNA molecular markers because of their high abundance and stability, as well as their regulatory roles in basic development. It provides clues for the diagnosis, prognosis and monitoring of a variety of complex diseases, including rheumatic and immune diseases. This article describes the characterization of cell-free non-coding RNAs and bioinformatics strategies, and summarizes cell-free non-coding RNA biomarkers associated with rheumatic and immune diseases. Prospects and reflections are made on the further research and clinical application of cell-free RNA markers.