The role of microRNA in the development of liver diseases. Part 2

Abstract

The scientific review shows the role of miRNA in the development of liver diseases, namely hepatocellular carcinoma. To write the article, we have searched for information in the Scopus, Web of Science, MedLine, PubMed, Google Scholar, ­EMBASE, Global Health, The Cochrane Library databases. In the development of hepatocellular carcinoma, the role of miRNAs involved in the regulation of the cell cycle, apoptosis, invasion, metastasis, and angiogenesis is emphasized. Scientists believe that loss of ­miR-122 expression in liver cancer correlates with inhibition of the liver phenotype and increased risk of metastasis. It is noted that the development of hepatocellular carcinoma is accompanied by an increase in the level of let-7, miR-26, miR-101 and a decrease in the concentration of miR-17-92, miR-181, miR-221 in blood serum, which can be used as diagnostic criteria. MiR-21 is considered a typical onco-microRNA and the level of circulating miR-21 in peripheral blood can serve as a potential biomarker of the early stage of hepatocellular carcinoma. In hepatocellular carcinoma, a low content of miR-34 is noted, which leads to the activation of the cyclin Е and an increase in the proliferative potential, which favors hepatocarcinogenesis. MiR-34a has an inhibitory effect on almost all oncogenic cellular processes. The researchers demonstrated that the change in the microRNA spectrum is mediated by the primary change in the generation of some circular single-stranded RNAs — circular RNAs. Thus, scientific studies of recent years confirm that miRNAs in the development of hepatocellular carcinoma are involved in the regulation of the cell cycle, apoptosis, invasion, metastasis, angiogenesis. As a potential biomarker of the early stage of hepatocellular carcinoma, the researchers identify the level of miR-21 in blood serum and consider it a typical onco-microRNA. MiR-34a has an inhibitory effect on almost all oncogenic cellular processes in hepatocellular carcinoma. Therefore, microRNAs play a very important role in the development of hepatocellular carcinoma and can be used as diagnostic and prognostic criteria, and factors of pathogenesis whose medicinal modulation will contribute to increasing the effectiveness of therapy.