Identification of potential biomarkers for diagnosis of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has a high mortality rate owing to its complexity. Identification of abnormally expressed genes in HCC tissues compared to those in normal liver tissues is a viable strategy for investigating the mechanisms of HCC tumorigenesis and progression as a means of developing novel treatments. A significant advantage of the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) is that the data therein were collected from different independent researchers and may be integrated, allowing for a more robust data analysis. Accordingly, in the present study, the gene expression profiles for HCC and control samples were downloaded from the GEO and TCGA. Functional enrichment analysis was performed using a Metascape dataset, and a protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes/proteins (STRING) online database. The prognostic value of mRNA for HCC was assessed using the Kaplan-Meier Plotter, a public online tool. A gene mRNA heatmap and DNA amplification numbers were obtained from cBioPortal. A total of 2,553 upregulated genes were identified. Functional enrichment analysis revealed that these differentially expressed genes (DEGs) were mainly accumulated in metabolism of RNA and the cell cycle. Considering the complexity and heterogeneity of the molecular alterations in HCC, multiple genes for the prognostication of patients with HCC are more reliable than a single gene. Thus, the PPI network and univariate Cox regression analysis were applied to screen candidate genes (small nuclear ribonucleoprotein polypeptide B and B1, nucleoporin 37, Rac GTPase activating protein 1, kinesin family member 20A, minichromosome maintenance 10 replication initiation factor, ubiquitin conjugating enzyme E2 C and hyaluronan mediated motility receptor) that are associated with the overall survival and progression-free survival of patients with HCC. In conclusion, the present study identified a set of genes that are associated with overall survival and progression-free survival of patients with HCC, providing valuable information for the prognosis of HCC.

MAPRE1 promotes cell cycle progression of hepatocellular carcinoma cells by interacting with CDK2.

Targeting cyclin-dependent kinases (CDKs) is a promising method of therapy for cancer. Unfortunately, the efficacy of CDK inhibitors in hepatocellular carcinoma (HCC) is limited, due in part to incomplete understanding of cell cycle progression and a lack of specific biomarkers to adequately identify which patients may be responsive to CDK inhibitors. In the present study, we report that microtubule-associated protein RP/EB family member 1 (MAPRE1), a gene involved in cell cycle and microtubule regulation, is significantly increased in HCC tissue, promotes HCC cell proliferation, enhances in vitro tumorigenesis, and associates with poor prognosis of HCC. We demonstrate that MAPRE1 binds with CDK2, resulting in the hyperphosphorylation of the CDK2 Thr161 residue in HCC cells. Our findings reveal that targeting MAPRE1 might be an effective therapeutic strategy in HCC, and suggest that MAPRE1 expression might provide a promising biomarker to stratify patients with HCC who may benefit from treatment with CDK inhibitors.

Downregulation of miR-610 promotes proliferation and tumorigenicity and activates Wnt/ß-catenin signaling in human hepatocellular carcinoma.

BACKGROUND: Wnt/ß-catenin signaling pathway plays important roles in human cancer progression. Better understanding the mechanism underlying regulation of Wnt/ß-catenin signaling pathway might provide novel therapeutic targets for cancer treatment. METHODS: miR-610 expression levels in hepatocellular carcinoma (HCC) cell lines, HCC tissues and 76 archived HCC specimens were determined using real-time PCR. Cell viability was measured by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. The level of DNA synthesis was determined by BrdU incorporation assay. Flow cytometry analysis was used to analyze cell cycle progression. The cells proliferation and tumorigenesis were determined by colony formation and anchorage-independent growth assays in vitro, and by xenograft tumors in vivo. Luciferase assay and micro-ribonucleoprotein complex immunoprecipitation assay were used to confirm the association of the targeted mRNAs with miR-610. RESULTS: miR-610 was downregulated in human HCC cells and tissues, and correlated with HCC progression and patient survival. Inhibition of miR-610 promoted, but overexpression of miR-610 reduced, HCC cell proliferation and tumorigenicity both in vitro and in vivo. Furthermore, we found that inhibiting miR-610 activated, but overexpressing miR-610 decreased, the Wnt/ß-catenin activity through directly suppressing lipoprotein receptor-related protein 6 (LRP6) and transducin ß-like protein 1 (TBL1X). The in vitro analysis was consistent with the inverse correlation detected between miR-610 levels with expression of LRP6 and TBL1X in a cohort of human HCC samples. CONCLUSIONS: Our results indicate that miR-610 downregulation plays essential roles in HCC progression and reduced miR-610 is correlated with Wnt/ß-catenin signaling pathway.