MiR-122 as a Regulator of Mitochondrial Metabolic Gene Network in Hepatocellular Carcinoma

ABSTRACT: Hepatocellular carcinoma (HCC) is the leading cause of cancer-related deaths worldwide, reflecting the need for a better understanding of hepatocarcinogenesis. In this study, we examined the genome-wide expression profiles of both miRNAs and mRNAs from paired tumor and adjacent non-tumor tissues from a cohort of 96 HCC patients in Hong Kong where hepatitis B virus (HBV) is endemic. The comprehensive analysis of the coordinate expression of miRNAs and mRNAs reveals that miR-122 is under-expressed in HCC and that it is an important regulator for normal mitochondrial metabolism. A decreased level of miR-122 leads to an increase in expression of miR-122 seed-matched genes, a loss of mitochondrial metabolic function, and a decrease in the expression of many miR-122 secondary targets. These secondary targets are prognostic markers for HCC patients. Transcriptome profiling data from an additional 180 HCC and 40 liver cirrhotic patients in the same cohort were used to confirm the anti-correlation of miR-122 primary and secondary target gene sets. To test the HCC findings in normal mouse liver, we used an antagomir against miR-122 and identified altered gene expression profiling by microarray analysis in mouse in vivo experiments. The mouse data recapitulated the human HCC findings. Our anti-miR122 data further provided a direct link between increases in the mRNA levels of miR-122 controlled genes and impairments of mitochondrial metabolism. In summary, we find miR-122 loss may be detrimental to mitochondrial-related metabolisms in sustaining critical liver function and contribute to the morbidity and mortality of liver cancer patients.

ORGANISM(S): Mus musculus Homo sapiens

PROVIDER: GSE22058 | GEO | 2010/06/09

SECONDARY ACCESSION(S): PRJNA128963

REPOSITORIES: GEO