AGO2 Mediates MYC mRNA Stability in Hepatocellular Carcinoma

Mol Cancer Res. 2020 Apr;18(4):612-622. doi: 10.1158/1541-7786.MCR-19-0805. Epub 2020 Jan 15.

Abstract

Deregulated RNA-binding proteins (RBP), such as Argonaute 2 (AGO2), mediate tumor-promoting transcriptomic changes during carcinogenesis, including hepatocellular carcinoma (HCC). While AGO2 is well characterized as a member of the RNA-induced silencing complex (RISC), which represses gene expression through miRNAs, its role as a bona fide RBP remains unclear. In this study, we investigated AGO2's role as an RBP that regulates the MYC transcript to promote HCC. Using mRNA and miRNA arrays from patients with HCC, we demonstrate that HCCs with elevated AGO2 levels are more likely to have the mRNA transcriptome deregulated and are associated with poor survival. Moreover, AGO2 overexpression stabilizes the MYC transcript independent of miRNAs. These observations provide a novel mechanism of gene regulation by AGO2 and provide further insights into the potential functions of AGO2 as an RBP in addition to RISC. IMPLICATIONS: Authors demonstrate that the RBP Argonaute 2 stabilizes the MYC transcript to promote HCC.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Animals
  • Argonaute Proteins / genetics*
  • Argonaute Proteins / metabolism
  • Carcinoma, Hepatocellular / genetics*
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • Genes, myc*
  • Heterografts
  • Humans
  • Liver Neoplasms / genetics*
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Mice
  • Mice, Inbred NOD
  • Mice, Nude
  • Mice, SCID
  • Proto-Oncogene Proteins c-myc / genetics*
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Transfection

Substances

  • AGO2 protein, human
  • Argonaute Proteins
  • MYC protein, human
  • Proto-Oncogene Proteins c-myc
  • RNA, Messenger