A high incidence of tumor recurrence and metastasis has been reported in hepatocellular carcinoma (HCC) patients; however, the underlying molecular mechanisms are largely unknown. In the present study a novel metastasis-related gene, eukaryotic initiation factor 5A2 (EIF5A2), was characterized for its role in HCC metastasis and underlying molecular mechanisms. Overexpression of EIF5A2 messenger RNA (mRNA) was detected in 50/81 (61.7%) of HCCs, which was significantly higher than those in nontumorous liver tissues. A worldwide increase in mortality associated with hepatocellular carcinoma (HCC) has recently been reported. 1,2 Clinical treatment of HCC remains challenging due to a high incidence of tumor recurrence. The main cause of death in HCC patients is intrahepatic metastasis but the underlying mechanisms are still not fully understood. It is generally believed that to give rise to a metastatic tumor, cancer cells from a primary site must complete all of the following steps: invasion, intravasation, survival and arrest in the blood stream, extravasation, and colonization at a new site. The motility of cancer cells, driven by the actin cytoskeleton network, has been well documented to play crucial roles at multiple steps during the metastasis process.

The poor prognosis of hepatocellular carcinoma (HCC) has been associated with recurrence and metastasis. Recently, we established a pair of HCC cell lines from a primary (H2-P) and its matched metastatic (H2-M) HCC tumors. A high density of cDNA microarray with 9184 human cDNA was used to identify the differentially expressed genes between H2-P and H2-M. Comparing with H2-P, eight upregulated and six downregulated genes were detected in H2-M. One interesting finding is the overexpression of Vimentin (VIM), a well-defined intermediate filament, which has been linked to a more aggressive status in various tumors. The correlation of overexpression of VIM and HCC metastasis was studied by immunohistochemistry using a tissue microarray with 200 primary HCCs and 60 pairs of primary and matched metastatic HCC samples. Tissue microarray demonstrated that the overexpression of VIM was significantly associated with HCC metastasis (Po0.01). This finding strongly suggests that the overexpression of VIM may play an important role in the metastasis of HCC.

Purpose: X protein (HBx), a product of hepatitis B virus, has been closely associated with the development of hepatocellular carcinoma (HCC). Based on observations that the COOH-terminal truncated HBx was frequently detected in HCC, the aim of this study is to evaluate the function of COOH-terminal truncated HBx in hepatocarcinogenesis. Experimental Design: Expression pattern of HBx was analyzed by immunohistochemistry on tissue microarray containing 194 pairs of HCCs and their matched nontumor liver tissues. MIHA and HepG2 cells transfected with full-length (X2) and COOH-terminal truncated HBx (X1) were tested for their ability to grow in soft agar and form tumors in vivo. Proliferation and apoptosis were assessed using 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide inner salt and terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling assays, respectively. To gain additional insight, the expression profile of HepG2-X2 and HepG2-X1were compared using cDNA microarray. Results: COOH-terminal truncated HBx was frequently detected in HCCs (79.3%, n = 111), and our in vitro and in vivo studies showed that the truncated rather than the full-length HBx could effectively transform immortalized liver cell line MIHA. Interestingly, expression profiling revealed differential expression of key genes implicated in the control of cell cycle and apoptosis. Conclusions: These findings strongly suggest that the COOH-terminal truncated HBx plays a critical role in the HCC carcinogenesis via the activation of cell proliferation.Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third cause of cancer death in the world (1). The prognosis of HCC is very poor and the overall 5-year survival rate worldwide is estimated only f3%, mainly because of late diagnosis (2). Although the molecular pathogenesis of HCC remains elusive, the etiologic association between hepatitis B virus (HBV) infection and hepatocarcinogenesis has been established (3). Epidemiologic studies have shown that the relative risk of HCC among HBV carrier is 10-fold higher compared to noncarrier (4). Among the four proteins translated by HBV, the X-gene product (HBx) has been closely associated with the HCC carcinogenesis (5).HBx is a small protein with 154 amino acids, which is required for the establishment of viral infection. The correlation between HBx and HCC development has been extensively studied and oncogenic roles of HBx include the following: (a) the activation of a variety of transcription factors such as nuclear factor-nB (6), activator protein (7), and cAMPresponsive element binding protein/activating transcription factor 2 (8); (b) the interaction with cellular oncogenes such as Ras (9), Src (10), c-jun (11); and (c) the stimulation of cytoplasmic signal transduction pathways such as Ras-Rafmitogen-activated protein kinase pathway (7, 9), and cell stress -induced MEKK1-p38-cJNK pathway (12). One important question that needs to be answered is why HCC occurred only in a small percent...

To identify genes associated with tumor metastasis in hepatocellular carcinoma (HCC), gene expression profiles between a pair of primary HCC (H2-P) and their matched metastatic HCC (H2-M) were compared. Overexpression of clusterin (CLU) was found in H2-M cells. To determine the roles CLU played in HCC metastasis, CLU was transfected into H2-P cells. Overexpression of CLU in H2-P cells increased cell migration by twofold in vitro and formation of metastatic tumor nodules in liver by eightfold in vivo. To evaluate the correlation of CLU expression with HCC metastasis, the expression levels of CLU in HCCs were investigated using a tissue microarray (TMA) containing 104 pairs of primary HCCs and their matched metastases. The frequency of CLU overexpression increased significantly in metastatic HCCs (59.1%) compared with that in primary tumors (32.6%, Po0.001). To gain additional insight into the function of CLU, the expression profile of H2P-CLU was compared with vector-transfected H2-P cells by cDNA microarray. A total of 35 upregulated and 14 downregulated genes were detected in H2P-CLU. One of the upregulated genes known as YKL-40, which is implicated in matrix-remodeling and metastasis, was further studied using TMA. A significant correlation (Po0.001) between the expression levels of YKL-40 and CLU was observed, implying that the CLU-YKL-40 pathway may play an important role in HCC metastasis.

Amplification of 3q26 is one of the most frequent chromosomal alterations in many solid tumors, including ovarian, lung, esophageal, prostate, breast, and nasopharyngeal cancers. A candidate oncogene to eukaryotic initiation factor 5A2 (eIF-5A2), a member of eukaryotic initiation factor 5A subfamily, has been isolated from a frequently amplified region at 3q26.2. In this work, the tumorigenic ability of eIF-5A2 was demonstrated by anchorage-independent growth in soft agar and tumor formation in nude mice. Furthermore, antisense DNA against eIF-5A2 could inhibit cell growth in ovarian cancer cell line UACC-1598 with amplification of eIF-5A2 in form of double minutes. Cell growth rate in UACC-1598 was also inhibited when the expression level of EIF-5A2 was decreased by the reduction of the copy number of double minutes. The correlation of EIF-5A2 overexpression and clinical features of ovarian cancer was investigated using tissue microarray, and the result showed that eIF-5A2 overexpression was significantly associated with the advanced stage of ovarian cancer. These findings suggest that eIF-5A2 plays important roles in ovarian pathogenesis.

Although the integration of hepatitis B virus (HBV) into human DNA has been found to be associated with the development of hepatocellular carcinoma (HCC), the molecular mechanism remains unclear. In order to obtain additional insight into the correlation of HBV integration and HCC development, integrated HBV in 14 primary HCC cases was isolated and characterized by sequencing analysis. Our findings in this study showed that: (1) none of the known cellular oncogene or tumor suppressor gene was affected by the HBV integration; (2) although the integration of HBV is random, the integration site was often within or close to human repetitive sequences; (3) integrated HBV may possess the capacity to transpose to another chromosome region through reintegration; (4) rearrangements of HBV sequence were observed in all the 14 integrants, involving (most frequently) X (12/14 integrants), P (8/14), S (7/14), and C (7/14) genes; and (5) 3 0 -deleted X gene and consequent C-terminal truncated X protein caused by HBV integration was observed in 10 cases. These deletions cause the losses of p53-dependent transcriptional repression binding site, transcription factor Sp1 binding site, and growth-suppressive effect domain, leading to cell proliferation and transformation. This finding suggests that 3 0 -deleted X gene caused by the HBV integration may play an important role in the HCC development.

BACKGROUND Recently, tumorigenic roles of the clusterin gene in several human malignancies have been suggested, but its potential role in the development and progression of ovarian carcinoma is unclear. METHODS In the current study, immunohistochemistry was used to examine the expression status of clusterin in 10 normal ovaries, 20 ovarian cystadenomas, 15 borderline ovarian tumors, and 240 ovarian carcinomas (nonmetastatic and metastatic) by tissue microarray. In addition, the apoptotic index of each tumor was assessed with a terminal deoxyuridine triphosphate nick‐end labeling assay. RESULTS Positive staining for clusterin in different ovarian tissues was observed primarily a cytoplasmic pattern. Cytoplasmic overexpression of clusterin was detected in none of the normal ovaries, in 17% of cystadenomas, in 38% of borderline tumors, and in 58% of invasive ovarian carcinomas. A significant association was observed (P < 0.001) between the overexpression of clusterin and late clinical stage according to the International Federation of Gynecology and Obstetrics staging system. In addition, the overexpression of clusterin was detected more frequently in metastatic lesions than that in their matched primary tumors. The current results also provided evidence that the overexpression of cytoplasmic clusterin in carcinomas was correlated inversely with the tumors' apoptotic index, demonstrating an antiapoptotic function of cytoplasmic clusterin in ovarian carcinomas. CONCLUSIONS The current results suggested that the overexpression of cytoplasmic clusterin may represent an acquired malignant phenotypic feature of ovarian carcinoma and may be one of the important factors in determining the aggressive nature of ovarian carcinoma. Cancer 2005. © 2004 American Cancer Society.

Serum samples were taken from 57 patients with sporadic non-A, -B, and -C (Non A, B, C) acute hepatitis at different times after onset of the disease and tested for the presence of the hepatitis E virus (HEV) RNA, IgM, and low avidity IgG antibodies. The viral antibodies were detected using two ELISA. One assay (GL) was produced using a mixture of recombinant peptides specified by ORF2 and ORF3 of the viral genome. The other was produced with an ORF2 specified peptide, pE2. The latter occurs naturally as homodimer, it is recognized strongly in its dimeric form by human sera and, in the primate model, it confers protection against experimental HEV infection. Nineteen samples were positive for one or more of these acute markers of HEV infection, 14 of which were acute sera with elevated ALT levels and 5 were convalescent sera with normal ALT level. The results showed that icteric phase of sporadic hepatitis lasts for about 17 days and it coincides with a period when viremia is subsiding as HEV antibodies are developing. Viremia was intermittent and all but one of the 5 instances were confined to the icteric phase with elevated ALT levels. On two of these occasions, viremia preceded detection of HEV antibody, on another 2 occasions it was concurrent with the detection of pE2 specific IgM and/or low avidity IgG and only in one case of protracted viremia was the viral genome detected concurrently with avid pE2 IgG antibody. Ten (71%) of the 14 acute sera were reactive for pE2 IgM, eight (57%) were reactive for low avidity pE2 IgG, and six (43%) for the GL IgM. The sensitivity for the diagnosis of acute hepatitis E may be increased to 87% by combining pE2 IgM and viremia. GL IgM was detected later, but persisted for a longer period of time than the pE2 antibodies, and it was the only acute antibody detected in the convalescent sera.