miR-192-5p Silencing by Genetic Aberrations Is a Key Event in Hepatocellular Carcinomas with Cancer Stem Cell Features

Abstract

Various cancer stem cell (CSC) biomarkers have been identified for hepatocellular carcinoma (HCC), but little is known about the implications of heterogeneity and shared molecular networks within the CSC population. Through miRNA profile analysis in an HCC cohort (n ¼ 241) for five groups of CSC þ HCC tissues, i.e., EpCAM þ , CD90 þ , CD133 þ , CD44 þ , and CD24 þ HCC, we identified a 14-miRNA signature commonly altered among these five groups of CSC þ HCC. miR-192-5p, the top-ranked CSC miRNA, was liver-abundant and-specific and markedly downregulated in all five groups of CSC þ HCC from two independent cohorts (n ¼ 613). Suppressing miR-192-5p in HCC cells significantly increased multiple CSC populations and CSC-related features through targeting PABPC4. Both TP53 mutation and hypermethylation of the mir-192 promoter impeded transcriptional activation of miR-192-5p in HCC cell lines and primary CSC þ HCC. This study reveals the circuit from hypermethylation of the mir-192 promoter through the increase in PABPC4 as a shared genetic regulatory pathway in various groups of primary CSC þ HCC. This circuit may be the driver that steers liver cells toward hepatic CSC cells, leading to hepatic carcinogenesis. Significance: miR-192-5p and its regulatory pathway is significantly abolished in multiple groups of HCC expressing high levels of CSC markers, which may represent a key event for hepatic carcinogenesis.

Loss of MiR-192 Initiates a Hyperglycolysis and Stemness Positive Feedback in Hepatocellular Carcinoma

“…Omics dataset A total of ve datasets from two HCC cohorts with 548 cases were used. In Cohort 1, there were a total of 176 Asian HCC cases, among which all cases had miRNA transcriptome (GSE6857) and mRNA transcriptome (GSE14520) and 22 cases had available metabolomics data [12,13,[15][16][17][18] (Fig. 1a).…”

“…Human liver cancer cell lines including HLF, HLE, Huh7 and HepG2 cells; human embryonic kidney HEK293T cells; human hepatic stellate cell (HSC) line LX2 cells; human hepatocyte line HL7702 cells; and human leukemic monocyte cell line THP1 (with macrophage activation) were used in this study as described before [13,19]. HLF, HLE and HuH7 were originally from JCRB, whereas HepG2, 293T and THP1 were from ATCC, and LX2 and HL7702 were from Chinese Academy of Sciences (Shanghai, China).…”

“…For infection, 5 MOI of each lentivirus was used for all our studies. pMiR-Report-control (Luc-Ctrl), pmiR-192 reporter (192-pos reporter), and miRZip-192 reporter (Zip192 reporter) were constructed before [13]. The miR-192 binding regions in the 3'UTR or coding region of GLUT1, PFKPB3, and MYC were inserted into the monoclonal sites (HindIII/SpeI) of the pMiR-Report plasmid to make the corresponding luciferase constructs.…”

“…In this case, it is feasible and essential to investigate the key metabolic features being shared among different CSC biomarker positive HCCs. is the 2 nd most abundant miRNA in the liver [13]. Its genetic silencing frequently occurs in many groups of hepatic CSC marker-positive HCCs such as EpCAM + , CD90 + , CD133 + , CD44 + and CD24 + HCCs, as well as pluripotency marker-positive HCCs.…”

“…Its genetic silencing frequently occurs in many groups of hepatic CSC marker-positive HCCs such as EpCAM + , CD90 + , CD133 + , CD44 + and CD24 + HCCs, as well as pluripotency marker-positive HCCs. HCC cells with miR-192 loss displayed a highly invasive phenotype and essential CSC features partially via the p53/miR-192/PABPC4 pathway [13,14]. Given these, investigating the key metabolic feature in HCCs with miR-192 loss might allow us to explore the essential metabolic properties of multiple different groups of CSC + HCCs.…”