miRNAs in patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis.
BACKGROUND & AIMS
microRNAs (miRNAs) are deregulated in non-alcoholic fatty liver disease (NAFLD) and have been proposed as useful markers for the diagnosis and stratification of disease severity. We conducted a meta-analysis to identify the potential usefulness of miRNA biomarkers in the diagnosis and stratification of NAFLD severity.


METHODS
After a systematic review, circulating miRNA expression consistency and mean fold-changes were analysed using a vote-counting strategy. The sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio and area under the curve (AUC) for the diagnosis of NAFLD or non-alcoholic steatohepatitis (NASH) were pooled using a bivariate meta-analysis. Deeks' funnel plot was used to assess the publication bias.


RESULTS
Thirty-seven studies of miRNA expression profiles and six studies of diagnostic accuracy were ultimately included in the quantitative analysis. miRNA-122 and miRNA-192 showed consistent upregulation. miRNA-122 was upregulated in every scenario used to distinguish NAFLD severity. The miRNA expression correlation between the serum and liver tissue was inconsistent across studies. miRNA-122 distinguished NAFLD from healthy controls with an AUC of 0.82 (95% CI 0.75-0.89), and miRNA-34a distinguished non-alcoholic steatohepatitis (NASH) from non-alcoholic fatty liver (NAFL) with an AUC of 0.78 (95% CI 0.67-0.88).


CONCLUSION
miRNA-34a, miRNA-122 and miRNA-192 were identified as potential diagnostic markers to segregate NAFL from NASH. Both miRNA-122, in distinguishing NAFLD from healthy controls, and miRNA-34a, in distinguishing NASH from NAFL, showed moderate diagnostic accuracy. miRNA-122 was upregulated in every scenario of NAFL, NASH and fibrosis. LAY SUMMARY: microRNAs are deregulated in non-alcoholic fatty liver disease. The microRNAs, miRNA-34a, miRNA-122 and miRNA-192, were identified as potential biomarkers of non-alcoholic fatty liver and non-alcoholic steatohepatitis, at different stages of disease severity. The correlation between miRNA expression in the serum and in liver tissue was inconsistent, or even inverse.
['Liu|Chang-Hai|CH|', 'Ampuero|Javier|J|', 'Gil-Gómez|Antonio|A|', 'Montero-Vallejo|Rocío|R|', 'Rojas|Ángela|Á|', 'Muñoz-Hernández|Rocío|R|', 'Gallego-Durán|Rocío|R|', 'Romero-Gómez|Manuel|M|']
D015415:Biomarkers D006801:Humans D008103:Liver Cirrhosis D035683:MicroRNAs D065626:Non-alcoholic Fatty Liver Disease D012720:Severity of Illness Index D059467:Transcriptome D015854:Up-Regulation
miRNA Non-alcoholic fatty liver disease Expression profile Diagnostic accuracy