Concomitantly, there was an increase in the relative quantity of miRNA-21 (P = .001*) and serum levels of TGF-β1 ( P = .337) among HCV patients after receiving treatment.
These miRNAs were positively correlated with alanine aminotransferase and aspartate aminotransferase levels, and the relative expression levels were higher in hepatitis C virus-infected patients and lower in patients with Child-Pugh C cirrhosis. miR-122 and miR-885-5p levels were also positively correlated with γ-glutamyl transpeptidase concentrations. miR-21 was associated with transplant-free survival in univariate Cox regression analysis and remained independently associated with survival after adjustment for age, Child-Pugh classification, Model for End-stage Liver Disease score, and history of previous decompensation in multivariate Cox regression analysis.
To assess the expression of miR-21 in these overlapping comorbidities, we measured plasma miR-21 in HIV with and without PAH and then stratified by concomitant HCV infection.
In cirrhotic HCCs the downregulation of miR-24 was correlated with poorer prognosis in patients with HBV and HCV virus infections. miR-21 was generally upregulated in HCC tissues versus the corresponding peritumoral tissues, particularly in non-cirrhotic HCC.
Taken together, our results indicate that miR-21 is upregulated during HCV infection and negatively regulates IFN-α signaling through MyD88 and IRAK1 and may be a potential therapeutic target for antiviral intervention.
Whereas miR-21 extracellular levels were unchanged, extracellular levels of miR-122, miR-34a and to a lesser extent miR-16, steadily increased during the course of HCV infection, independently of viral replication and production.