Background: Alveolar echinococcosis is an infectious zoonotic disease caused by Echinococcus multilocularis that is endemic to the vast pastoral areas of southern Qinghai province of China. Alveolar echinococcosis affects the human liver, and its clinical manifestations are similar to those of liver tumors. It is also called “worm cancer,” as it induces irreversible liver fibrosis and brain metastases. Alveolar echinococcosis is a serious threat to human health and is a burden to patients and economies. When detected and treated early, patients with alveolar echinococcosis have a strong chance of recovery. Therefore, it is imperative to identify early diagnostic biomarkers of the disease. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNA molecules that play key roles in a wide range of biological processes, and have been recently implicated in tumorigenesis. However, little is known about the role of miRNAs in alveolar echinococcosis. We have previously reported differentially expressed miRNAs in the plasma of patients with alveolar echinococcosis and healthy individuals, using microarray assay chips.
Methods: We screened 10 differentially expressed miRNAs based on their fold change and the available literature. Additionally, quantitative polymerase chain reaction was used to verify their expression in the plasma of alveolar echinococcosis patients. We found that hsa-miR-125b-5p was upregulated in the plasma and the hepatic tissue samples of alveolar echinococcosis patients; therefore, its role as a diagnostic biomarker for alveolar echinococcosis was investigated. Accordingly, hsa-miR-125b-5p was upregulated in plasma and hepatic tissue samples obtained from alveolar echinococcosis patients. Receiver operating characteristic curves showed that hsa-miR-125b-5p was associated with an area under the curve of 99.8% and 98.9% in the plasma and hepatic tissues of alveolar echinococcosis patients, respectively. Transfection of an LV-hsa-miR-125b-5p-inhibitor reduced apoptosis of L-O2 hepatocytes in vitro (P < 0.05). Thus, hsa-miR-125b-5p may promote liver cell proliferation and inhibit liver cell apoptosis.
Conclusions: Taken together, hsa-miR-125b-5p may be a promising diagnostic biomarker for the early non-invasive diagnosis of alveolar echinococcosis. We plan to validate the expression of hsa-miR-125b-5p in the plasma of patients with cystic echinococcosis, alveolar echinococcosis, and other liver diseases to determine the potential of hsa-miR-125-5p as a differential biomarker in future studies.