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Background: Mutations in HBx gene are frequently found in HBV-associated hepatocellular carcinoma (HCC). Activation of hypoxia-inducible factor-1α (HIF-1α) contributes to HCC development and progression. Wild-type HBx has been demonstrated to activate HIF-1α, but the effect of HBx mutations on HIF-1α has not been elucidated.Methods: HBx mutations were identified by gene sequencing in 101 HCC tissues. Representative HBx mutants were cloned and transfected into HCC cells. Expression and activation of HIF-1α were analysed by western blot and luciferase assays, respectively. The relationship between HBx mutants and HIF-1α expression in HCC tissues was also evaluated.Results: The dual mutations K130M/V131I enhanced the functionality of HBx as they upregulated the expression and transcriptional activity of HIF-1α. The C-terminal truncations and deletion mutations, however, weakened the ability of HBx to upregulate HIF-1α. Meanwhile, the C-terminus was further found to be essential for the stability and transactivation of HBx. In the HCC tissues, there was a positive association between the HBx mutants and HIF-1α expression.Conclusion: Different mutations of HBx exert differentiated effects on the functionality of HIF-1α, however, the overall activity of HBx mutants appears to increase the expression and transcriptional activity of HIF-1α. [ABSTRACT FROM AUTHOR]

Nasopharyngeal carcinoma (NPC) is an aggressive head and neck cancer characterized by Epstein-Barr virus (EBV) infection and dense lymphocyte infiltration. The scarcity of NPC genomic data hinders the understanding of NPC biology, disease progression and rational therapy design. Here we performed whole-exome sequencing (WES) on 111 micro-dissected EBV-positive NPCs, with 15 cases subjected to further whole-genome sequencing (WGS), to determine its mutational landscape. We identified enrichment for genomic aberrations of multiple negative regulators of the NF-κB pathway, including CYLD, TRAF3, NFKBIA and NLRC5, in a total of 41% of cases. Functional analysis confirmed inactivating CYLD mutations as drivers for NPC cell growth. The EBV oncoprotein latent membrane protein 1 (LMP1) functions to constitutively activate NF-κB signalling, and we observed mutual exclusivity among tumours with somatic NF-κB pathway aberrations and LMP1-overexpression, suggesting that NF-κB activation is selected for by both somatic and viral events during NPC pathogenesis.

A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor, called tumor-initiating cells (TICs) or cancer stem cells (CSCs). Here we describe the identification and characterization of such cells from hepatocellular carcinoma (HCC) using the marker CD133. CD133 accounts for approximately 1.3%-13.6% of the cells in the bulk tumor of human primary HCC samples. When compared with their CD133- counterparts, CD133+ cells not only possess the preferential ability to form undifferentiated tumor spheroids in vitro but also express an enhanced level of stem cell-associated genes, have a greater ability to form tumors when implanted orthotopically in immunodeficient mice, and can be serially passaged into secondary animal recipients. Xenografts resemble the original human tumor and maintain a similar percentage of tumorigenic CD133+ cells. Quantitative PCR analysis of 41 separate HCC tissue specimens with follow-up data found that CD133+ tumor cells were frequently detected at low quantities in HCC, and their presence was also associated with worse overall survival and higher recurrence rates. Subsequent differential microRNA expression profiling of CD133+ and CD133- cells from human HCC clinical specimens and cell lines identified an overexpression of miR-130b in CD133+ TICs. Functional studies on miR-130b lentiviral-transduced CD133- cells demonstrated superior resistance to chemotherapeutic agents, enhanced tumorigenicity in vivo, and a greater potential for self renewal. Conversely, antagonizing miR-130b in CD133+ TICs yielded an opposing effect. The increased miR-130b paralleled the reduced TP53INP1, a known miR-130b target. Silencing TP53INP1 in CD133- cells enhanced both self renewal and tumorigenicity in vivo. Collectively, miR-130b regulates CD133+ liver TICs, in part, via silencing TP53INP1. [ABSTRACT FROM AUTHOR]

Purpose: To compare the embolization efficacy and treatment effectiveness of transarterial ethanol ablation (TEA) versus those of chemoembolization and evaluate the correlation between embolization efficacy and treatment effectiveness of these treatments for hepatocellular carcinoma (HCC). Materials and Methods: A case-controlled study was undertaken with 30 patients in each group matched based on Child-Pugh grade, tumor characteristics, and performance status. Primary endpoints were embolization efficacy (ie, Lipiodol retention within tumor at 2 months) and treatment effectiveness as evaluated by tumor response, disease progression, progression-free survival, and overall survival. The secondary endpoint was correlation between embolization efficacy and treatment effectiveness. Results: Lipiodol retention was greater in the TEA group (89.5% +/- 10.7% vs 47.5% +/- 21.2%; P < .0001). The tumor progression rate at 1 year was higher in the chemoembolization group (five of 30 vs zero of 30; P = .0261). One- and 2-year overall survival rates were higher in the TEA group (93.3% and 80.0%, respectively, vs 73.3% and 43.3%, respectively; P = .0053). One- and 2-year extrahepatic disease progression rates were lower in the TEA group (P = .0002). There were no differences in progression-free survival and intrahepatic disease progression rates at 1 and 2 years. Patients with greater Lipiodol retention (ie, >60%) had better treatment outcomes at 1 year than those with lesser retention, with higher overall survival rates (88.9% vs 66.7%; P = .0192), lower intrahepatic disease progression rates (25.6% vs 59.4%; P = .0169), lower extrahepatic disease progression rates (0.31% vs 35.5%; P = .0047), and higher progression-free survival rates (72.1% vs 36.3%; P = .005). Conclusions: The embolization efficacy and treatment effectiveness of TEA are probably superior to those of chemoembolization for HCC. [ABSTRACT FROM AUTHOR]

Background & Aims: Recent studies have emphasized causative links between microRNA (miRNA) deregulations and cancer development. In hepatocellular carcinoma (HCC), information on differentially expressed miRNA remained largely undefined. Methods: Array-based miRNA profiling was performed on HCC cells that were derived from chronic carriers of hepatitis B virus (HBV) and hepatitis C virus (HCV), and nonviral-associated patients. Specific microRNA (miR)-223 and miR-222 deregulations were verified in an independent series of tumors. The functional effect of miR-223 was examined further. An integrative analysis of messenger RNA (mRNA) array with in silico predictions defined potential downstream targets of miR-223. A luciferase reporter assay was conducted to confirm target association. Results: Distinct up-regulations of miR-222, miR-221, and miR-31, and down-regulations of miR-223, miR-126, and miR-122a were identified. Further investigations suggested the highly deregulated miR-223 and miR-222 could unequivocally distinguish HCC from adjacent nontumoral liver, irrespective of viral associations (P ≤ .0002). Re-expression of miR-223 in HBV, HCV, and non-HBV non-HCV–related HCC cell lines revealed a consistent inhibitory effect on cell viability (P < .01). Integrative analysis further implicated Stathmin 1 (STMN1) as a downstream target of miR-223. A strong inverse relationship between STMN1 mRNA and miR-223 expressions was shown (P = .006). A substantial reduction in STMN1 protein was further demonstrated upon restoration of miR-223 expression in HCC cell lines. We further showed that miR-223 readily could suppress the luciferase activity in reporter construct containing the STMN1 3'' untranslated region (P = .02). Conclusions: Our study revealed specific miRNA differential expressions in HCC and underscores the potential importance of miR-223 down-regulations in the development of HCC. [Copyright &y& Elsevier]

Purpose: This prospective trial aimed to evaluate the safety and effectiveness of transarterial ethanol ablation (TEA) of intrahepatic lesions of hepatocellular carcinoma (HCC) with a Lipiodol-ethanol mixture. Materials and Methods: Seventy-seven patients were recruited and 164 lesions (mean size, 5.2 cm +/- 3.0) were treated. Inclusion criteria included histologic proof of HCC, refusal of (n = 9) or contraindication to (n = 68) surgical resection, Eastern Cooperative Oncology Group performance status no greater than 2, and intrahepatic disease without vascular invasion. The mixture consisted of 33% ethanol by volume, with the total dose of Lipiodol-ethanol mixture limited to 60 mL for each treatment session. The primary endpoint was patient survival. Secondary endpoints were tumor response, adverse effects of treatment, and progression-free survival. Median follow-up time for the whole cohort was 2.3 years. Results: Median overall survival was 2.2 years. Overall survival and progression-free survival rates at 1 year and 2 years were 77.9% and 50.1% and 63.6% and 46.3%, respectively. Complete ablation according to radiologic criteria was achieved in 61 patients (79.2%) and 86% of the 164 treated lesions. Mean tumor volume reduction was 65.22%. Patient survival was significantly better in patients with tumors no larger than 5 cm (Cox proportional-hazards regression, P = .0074). Treatment response was significantly better for patients with tumors no greater than 7 cm (chi2 test, P = .0462; Fisher exact test, P = .0326). Adverse effects included irreversible hepatic decompensation (0.6% of procedures), pain (4.8%), and fever (13.8%). Conclusions: TEA is a safe and effective means to establish local control of unresectable and resectable intrahepatic lesions of HCC. [ABSTRACT FROM AUTHOR]

Improvement in surgical outcomes of liver resection has been achieved in the past decade. Among other factors, a gradual change of technology platforms and refinement of surgical techniques have played significant roles. In this review, the various surgical approaches, operative techniques, operative instruments, and adjunctive measures as applied in liver resection are described, along with discussion of the pros and cons of each of these attributes. A brief description of laparoscopic liver resection is also included to address this important and emerging area in liver surgery. [ABSTRACT FROM AUTHOR]

Summary: Information on the clonal relationship between tumor nodules in patients diagnosed with hepatocellular carcinoma (HCC) holds prognostic significance in the prediction of recurrence and postoperative treatment. Here, we investigated the clonal relationships in 11 focal nodules from 5 patients with HCC by comparative genomic hybridization (CGH) and spectral karyotyping. CGH analysis indicated tumor nodules in 5 (100%) of 5 cases to share similar patterns of genomic imbalances, suggesting nodules to be clonally related. This clonal relationship was further substantiated in 2 cases, where spectral karyotyping analysis indicated identical structural rearrangements between focal tumors. Few studies have attempted to differentiate multicentric growth from intrahepatic dissemination in HCC using CGH analysis; however, data interpretation remained subjective. In this study, we have extended our data to include published CGH findings on 57 nodules derived from 19 HCC cases. Simulation of CGH findings by unsupervised 2-way hierarchical clustering indicated tumor nodules in 20 (83.3%) of 24 cases to cluster concordantly, signifying a high incidence of clonal similarity. In sum, bioinformatic analysis of genomic profiles may represent a reliable research tool in analyzing clonal relationships among tumor nodules. [Copyright &y& Elsevier]

Eicosapentaenoic acid (EPA) has been demonstrated to induce apoptosis and cell cycle arrest in various cancer cell lines in vitro. In this study, we investigated the anti-tumor effects of EPA on hepatoma cell lines and the mechanisms responsible for induced cell death. Three hepatoma cell lines tested had different p53 status: HepG2 with a wild-type p53; Hep3B, of which the endogenous p53 was deleted; and Huh7 with its p53 mutated. MTT assay showed reduced viability of HepG2 cells after exposure to EPA and the cytotoxicity of EPA was time and dose dependent. However, EPA had no effect on the viability and cell death in the two other hepatoma cell lines containing dysfunctional p53. DNA fragmentation analysis and TUNEL (terminal deoxynucleotidyl transferase [TdT)-mediated deoxyuridine diphosphate (dUTP] nick end labeling) staining showed a typical pattern of DNA laddering and DNA breaks staining, respectively, in wild-type p53-containing HepG2 cells after EPA treatment. We also observed that EPA induced transient nuclear accumulation of P53 protein that subsequently up-regulated the expression of Fas messenger RNA and protein in HepG2 cells. In contrast. these findings were not observed in Hep3B and Huh7 cells exposed to EPA. Most notably, EPA-induced apoptosis in HepG2 cells could be reduced almost completely by treatment with FasL antisense oligonucleotides. We conclude that EPA inhibits the growth of HepG2 cells and mediates its effect, at least in part, via the Fas-mediated apoptosis. It appears that the effects of EPA on hepatoma cells are determined by the status of p53 and that wild-type p53 is a prerequisite for the anticancer effect of EPA. [ABSTRACT FROM AUTHOR]

Background Although laparoscopic resection of colorectal carcinoma improves post-operative recovery, long-term survival and disease control are the determining factors for its application. We aimed to test the null hypothesis that there was no difference in survival after laparoscopic and open resection for rectosigmoid cancer.Methods From Sept 21, 1993, to Oct 21, 2002, 403 patients with rectosigmoid carcinoma were randomised to receive either laparoscopic assisted (n=203) or conventional open (n=200) resection of the tumour. Survival and disease-free interval were the main endpoints. Patients were last followed-up in March, 2003. Perioperative data were recorded and direct cost of operation estimated. Data were analysed by intention to treat.Findings The demographic data of the two groups were similar. After curative resection, the probabilities of survival at 5 years of the laparoscopic and open resection groups were 76·1% (SE 3·7%) and 72·9% (4·0%) respectively. The probabilities of being disease free at 5 years were 75·3% (3·7%) and 78·3% (3·7%), respectively. The operative time of the laparoscopic group was significantly longer, whereas postoperative recovery was significantly better than for the open resection group, but these benefits were at the expense of higher direct cost. The distal margin, the number of lymph nodes found in the resected specimen, overall morbidity and operative mortality did not differ between groups.Interpretation Laparoscopic resection of rectosigmoid carcinoma does not jeopardise survival and disease control of patients. The justification for adoption of laparoscopic technique would depend on the perceived value of its effectiveness in improving short-term post-operative outcomes. [Copyright &y& Elsevier]

Competing Interests: All authors have disclosed no conflicts of interest.