The role of microRNAs in modulating SARS-CoV-2 infection in human cells: a systematic review

MicroRNAs are gene expression regulators, associated with several human pathologies, including the ones caused by virus infections. Although their role in infection diseases is not completely known, they can exert double functions in the infected cell, by mediating the virus infection and/or regulating the immunity-related gene targets through complex networks of virus-host cell interactions. In this systematic review, the Pubmed, EMBASE, Scopus, Lilacs, Scielo, and EBSCO databases were searched for research articles published until October 22nd, 2020 that focused on describing the role, function, and/or association of miRNAs in SARS-CoV-2 human infection and COVID-19. Following the PRISMA 2009 protocol, 29 original research articles were selected. Most of the studies reported miRNA data based on the genome sequencing of SARS-CoV-2 isolates and computational prediction analysis. The latter predicted, by at least one independent study, 1266 host miRNAs to target the viral genome. Thirteen miRNAs were identified by four independent studies to target SARS-CoV-2 specific genes, suggested to act by interfering with their cleavage and/or translation process. The studies selected also reported on viral and host miRNAs that targeted host genes, on the expression levels of miRNAs in biological specimens of COVID-19 patients, and on the impact of viral genome mutations on miRNA function. Also, miRNAs that regulate the expression levels of the ACE2 and TMPRSS2 proteins, which are critical for the virus entrance in the host cells, were reported. In conclusion, despite the limited number of studies identified, based on the search terms and eligibility criteria applied, this systematic review provides evidence on the impact of miRNAs on SARS-CoV-2 infection and COVID-19. Although most of the reported viral/host miRNAs interactions were based on in silico prediction analysis, they demonstrate the relevance of the viral/host miRNA interaction for viral activity and host responses. In addition, the identified studies highlight the potential use of miRNAs as therapeutic targets against COVID-19, and other viral human diseases (This review was registered at the International Prospective Register of Systematic Reviews (PROSPERO) database (#CRD42020199290).