Identification of overexpressed genes in hepatocellular carcinoma, with special reference to ubiquitin-conjugating enzyme E2C gene expression.
ABSTRACT This study consisted of 2 aims: (i) to determine genes associated with hepatocellular carcinoma (HCC) by microarray analysis; and (ii) to evaluate the clinicopathological significance of human ubiquitin-conjugating enzyme E2C (Ube2c) found to be overexpressed in HCC from microarray analysis. Laser microdissection and cDNA-microarray were performed to identify genes associated with HCC. We then focused on the Ube2c gene. Using real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR), Ube2c expression status and clinicopathological significance were studied in 65 clinical HCC samples. A number of genes upregulated in HCC cells compared to noncancerous liver cells were identified, one of which was the Ube2c gene. Ube2c gene expression in the cancer tissue was higher than in the corresponding noncancerous tissue in 62 of the 65 cases (95.4%, p < 0.01). Tumors with high Ube2c expression showed higher frequencies of tumor invasion to capsular formation (fc-inf), invasion to portal vein (vp) and tumor de-differentiation (p < 0.05). Patients with high Ube2c expression also showed significantly worse disease-free survival rates than those with low Ube2c expression (p < 0.01). In addition, Ube2c expression was found to be an independent prognostic factor for disease-free survival rate in multivariate analysis. We identified differentially expressed genes between HCC and normal liver tissues. Of those, the Ube2c gene appeared to be associated with HCC progression, and may be useful as a prognostic indicator for HCC patients.
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ABSTRACT: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide with an extremely poor prognosis. The classification of HCC based on the molecular signature is not well-established. In the present study, we reported HCC signature genes based on the JNK1 activation status in 31 HCC specimens relative to the matched distal noncancerous liver tissue from 31 patients. The HCCs with high JNK1 (H-JNK1) and low JNK1 (L-JNK1) were sub-grouped. Two different signature gene sets for both H-JNK1 and L-JNK1 HCC were identified through gene expression profiling. A striking overlap of signature genes was observed between the H-JNK1 HCC and the hepatoblastoma or hepatoblastoma-type HCC. Many established biomarkers for hepatic progenitor cells were over-expressed in H-JNK1 HCC, including AFP, TACSTD1, KRT19, KRT7, THY1, and PROM1. In addition, the majority of the most up-regulated genes were those associated with metastasis and earlier recurrence, whereas the genes for normal liver function were substantially down-regulated in H-JNK1 HCC tissue. A Kaplan-Meier plot demonstrated that the survival of the patients with H-JNK1 HCC was severely impaired. Accordingly, we believe that the H-JNK1 HCC may originate from hepatic progenitor cells and is associated with poorer prognosis. The status of JNK1 activation in HCC tissue, thus, might be a new biomarker for HCC prognosis and therapeutic targeting.Molecular Cancer 09/2009; 8:64. · 3.99 Impact Factor