Recurrent chromosomal aberrations are often observed in hepatocellular carcinoma (HCC), but little is known about the functional non-coding sequences, particularly microRNAs (miRNAs), at the chromosomal breakpoints in HCC. Here we show that 22 miRNAs are often amplified or deleted in HCC. MicroRNA-151 (miR-151), a frequently amplified miRNA on 8q24.3, is correlated with intrahepatic metastasis of HCC. We further show that miR-151, which is often expressed together with its host gene FAK, encoding focal adhesion kinase, significantly increases HCC cell migration and invasion in vitro and in vivo, mainly through miR-151-5p, but not through miR-151-3p. Moreover, miR-151 exerts this function by directly targeting RhoGDIA, a putative metastasis suppressor in HCC, thus leading to the activation of Rac1, Cdc42 and Rho GTPases. In addition, miR-151 can function synergistically with FAK to enhance HCC cell motility and spreading. Thus, our findings indicate that chromosome gain of miR-151 is a crucial stimulus for tumour invasion and metastasis of HCC.

MicroRNAs (miRNAs) are important gene regulators, which are often deregulated in cancers. In this study, the authors analyzed the microRNAs profiles of 78 matched cancer/noncanerous liver tissues from HCC patients and 10 normal liver tissues and found that 69 miRNAs were differentially expressed between hepatocellular carcinoma (HCC) and corresponding noncancerous liver tissues (N). Then the expressions of 8 differentially expressed miRNAs were validated by real time RT PCR. The set of differentially expressed miRNAs could distinctly classify HCC, N and normal liver tissues (NL). Moreover, some of these differentially expressed miRNAs were related to the clinical factors of HCC patients. Most importantly, Kaplan-Meier estimates and the log-rank test showed that high expression of hsa-miR-125b was correlated with good survival of HCC patients (hazard ratio, 1.787, 95% confidence interval, 1.020-3.133, p 5 0.043). The transfection assay showed that overexpression of miR-125b in HCC cell line could obviously suppress the cell growth and phosporylation of Akt. In conclusion, the authors have demonstrated the diagnostic miRNA profile for HCC, and for the first time, identified the miR-125b with predictive significance for HCC prognosis.

The pathological relevance and significance of microRNAs (miRNAs) in hepatocarcinogenesis have attracted much attention in recent years; however, little is known about the underlying molecular mechanisms through which miRNAs are involved in the development and progression of hepatocellular carcinoma (HCC). In this study, we demonstrate that miR-30d is frequently up-regulated in HCC and that its expression is highly associated with the intrahepatic metastasis of HCC. Furthermore, the enhanced expression of miR-30d could promote HCC cell migration and invasion in vitro and intrahepatic and distal pulmonary metastasis in vivo, while silencing its expression resulted in a reduced migration and invasion. Galphai2 (GNAI2) was identified as the direct and functional target of miR-30d with integrated bioinformatics analysis and messenger RNA array assay. This regulation was further confirmed by luciferase reporter assays. In addition, our results, for the first time, showed that GNAI2 was frequently suppressed in HCC by way of quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining assays. The increase of the GNAI2 expression significantly inhibits, whereas knockdown of the GNAI2 expression remarkably enhances HCC cell migration and invasion, indicating that H epatocellular carcinoma (HCC) is one of the most prevalent malignancies and leading causes of death from cancer worldwide, especially in East Asia and South Africa. 1 The pathogenesis of HCC is a multistage process that is usually associated with preneoplastic liver lesions, chronic inflammation, and/or cirrhosis. Despite great advances in the treatment of the disease, relapse or metastasis is frequently observed in clinics, and the 5-year survival rate is still quite low among patients with HCC. 2 In past decades, studies have been performed to investigate the genes and proteins that underlie the development and progression of HCC. Several factors involved in the pathogenesis of this malignancy, including wnt/catenin, p53, Rb, and Ras/MAPK, 3 have been identified. However, the roles and significances of nonprotein coding genes with a particular focus on a class of endogenous tiny RNA molecules termed microRNA (miRNA) remain to be established in the pathogenic processes of HCC.miRNAs are approximately 21-to 25-nucleotide noncoding RNA molecules that are highly conserved in a variety of eukaryotic organisms. Since their initial discovery in Caenorhabditis elegans, 4 miRNAs have become widely accepted as posttranscriptional regulators of gene expression through directly degrading messenger RNA (mRNA) or indirectly repressing protein translation. 5 Recent progress suggests that deregulation of miRNAs is involved in a wide range of human diseases, including

Cancer cells possess a unique metabolic phenotype that allows them to preferentially utilize glucose through aerobic glycolysis. This phenomenon is referred to as the "Warburg effect." Accumulating evidence suggests that microRNAs (miRNAs), a class of small noncoding regulatory RNAs, interact with oncogenes/tumor suppressors and induce such metabolic reprograming in cancer cells. To systematically study the metabolic roles of miRNAs in cancer cells, we developed a gain-of-function miRNA screen in HeLa cells. Subsequent investigation of the characterized miRNAs indicated that miR-199a-5p acts as a suppressor for glucose metabolism. Furthermore, miR-199a-5p is often down-regulated in human liver cancer, and its low expression level was correlated with a low survival rate, large tumor size, poor tumor differentiation status, high tumornode-metastasis stage and the presence of tumor thrombus of patients. MicroRNA-199a-5p directly targets the 3 0 -untranslated region of hexokinase 2 (HK2), an enzyme that catalyzes the irreversible first step of glycolysis, thereby suppressing glucose consumption, lactate production, cellular glucose-6-phosphate and adenosine triphosphate levels, cell proliferation, and tumorigenesis of liver cancer cells. Moreover, HK2 is frequently up-regulated in liver cancer tissues and associated with poor patient outcomes. The up-regulation of hypoxiainducible factor-1a under hypoxic conditions suppresses the expression of miR-199a-5p and promotes glycolysis, whereas reintroduction of miR-199a-5p interferes with the expression of HK2, abrogating hypoxia-enhanced glycolysis. Conclusion: miR-199a-5p/HK2 reprograms the metabolic process in liver cancer cells and provides potential prognostic predictors for liver cancer patients. (HEPATOLOGY 2015;62:1132-1144

Angiopoietin-like protein 4 (ANGPTL4) plays complex and often contradictory roles in vascular biology and tumor metastasis, but little is known about its function in hepatocellular carcinoma (HCC) metastasis. In the present study, we showed that hypoxia-inducible factor 1a (HIF-1a) directly up-regulates ANGPTL4, and its stableness positively correlates with ANGPTL4 expression in HCC tissue. Overexpression of ANGPTL4 significantly increased HCC cell transendothelial migration in vitro and intrahepatic and distal pulmonary metastasis in vivo, whereas silencing ANGPTL4 expression or treatment with a neutralizing antibody specific for ANGPTL4 protein resulted in a reduced transendothelial migration. We also found that serum ANGPTL4 is higher in HCC patients, compared to healthy control, and correlates with intrahepatic metastasis and histological grade. Further, secreted ANGPTL4 promotes transendothelial migration and metastasis of HCC cells in vitro and in vivo through the up-regulation of vascular cell adhesion molecule-1 (VCAM-1) of human umbilical vein endothelial cells and the activation of the VCAM-1/ integrin b1 axis. Conclusion: ANGPTL4 is a target gene of HIF-1a and acts as an important regulator in the metastasis of HCC. Serum ANGPTL4 correlates with tumor progression and metastasis and might be used to indicate prognosis in HCC patients. (HEPATOLOGY 2011;54:910-919) Abbreviations: 2ME2, 2-methoxyestradiol; AFP, alpha-fetoprotein; ANGPTL4, angiopoietin-like protein 4; ChIP, chromatin immunoprecipitation; CM, conditioned medium; DFO, deferoxamine mesylate; HBV, hepatitis B virus; HCC, hepatocellular carcinoma; HIF-1a, hypoxia-inducible factor 1a; HREs, hypoxia-responsive elements; HUVECs, human umbilical vein endothelial cells; IgG, immunoglobulin G; IL-1b, interleukin-1 beta; IjB-b, inhibitor of nuclear factor kappa B beta; kb, kilobase; LPS, lipopolysaccharide; NF-jB, nuclear factor kappa light-chain enhancer of activated B cells; shRNA, short-hairpin RNA; VCAM-1, vascular cell adhesion molecule-1.From the