Hepatocellular carcinoma: prevention, detection and treatment … in the real world

Transcription factor AP-4 promotes tumorigenic capability and activates the Wnt/β-catenin pathway in hepatocellular carcinoma

It has been reported that the transcription factor activating enhancer-binding protein 4 (TFAP4) is upregulated and associated with an aggressive phenotype in several cancers. However, the precise mechanisms underlying the oncogenic role of TFAP4 remain largely unknown.

Methods: TFAP4 expression levels in hepatocellular carcinoma (HCC) cells and tissues were detected by quantitative real-time PCR (qPCR) and immunohistochemistry (IHC). In vitro and in vivo assays were performed to investigate the oncogenic function of TFAP4 in the tumor-initiating cell (TIC)-like phenotype and the tumorigenic capability of HCC cells. Luciferase reporter and chromatin immunoprecipitation (ChIP)-qPCR assays were performed to determine the underlying mechanism of TFAP4-mediated HCC aggressiveness.

Results: TFAP4 was markedly upregulated in human HCC, and was associated with significantly poorer overall and relapse-free survival in patients with HCC. Furthermore, we found that overexpression of TFAP4 significantly enhanced, whereas silencing TFAP4 inhibited, the tumor sphere formation ability and proportion of side-population cells in HCC cells in vitro, and ectopic TFAP4 enhanced the tumorigenicity of HCC cells in vivo. Mechanistically, we demonstrated that TFAP4 played an important role in activating Wnt/β-catenin signaling by directly binding to the promoters of DVL1 (dishevelled segment polarity protein 1) and LEF1 (lymphoid enhancer binding factor 1).

Conclusions: Our results provide new insight into the mechanisms underlying hyperactivation of the Wnt/β-catenin pathway in HCC, as well the oncogenic ability of TFAP4 to enhance the tumor-forming ability of HCC cells.

The Effect of ADAM8 on the Proliferation and Apoptosis of Hepatocytes and Hepatoma Carcinoma Cells

This study was undertaken to evaluate the effect of ADAM8 on the proliferation and apoptosis of hepatocytes and hepatoma carcinoma cells during hepatocellular carcinoma (HCC) progression. The expression of ADAM8 was significantly increased with good correlation of PCNA expression increasing and cells apoptosis decreasing during the progression of HCC in the liver of mice. Proliferation experiment in vitro showed that recombinant ADAM8 could induce the expression of PCNA in L02 cells, but not in HepG2 cells. Apoptosis experiment in vitro showed that recombinant ADAM8 did not induce or inhibit the expression of apoptosis-related factors Bcl2, Bax, and Caspase3 in L02 cells, but significantly induced the expression of Bcl2, inhibited the expression of Bax and Caspase3 in HepG2 cells. In conclusion, our study suggested that ADAM8 could promote the proliferation of normal hepatocytes and render hepatoma carcinoma cells more resistant to apoptosis to play important roles during the progression of HCC. ADAM8; Proliferation; Apoptosis.

Prognostic significance of BMP7 as an oncogene in hepatocellular carcinoma

This study aims to evaluate the association between BMP7 tissue expression and patient prognosis in hepatocellular carcinoma (HCC). The expression of BMP7 mRNA in HCC was characterized using real-time PCR and 30 pairs of fresh frozen HCC tissues and corresponding noncancerous tissues. BMP7 protein expression in HCC was confirmed using immunohistochemistry on a tissue microarray chip. Finally, BMP7 expression was correlated with conventional clinicopathological features of HCC and patient outcome. The expression of BMP7 mRNA and protein in HCC cells was much higher than in normal hepatic cells. Our results showed that the high expression of BMP7 in HCC was related to tumor size (p < 0.001), histological differentiation (p = 0.041), serum AFP (p = 0.007), and tumor stage (p < 0.001). Kaplan-Meier survival analysis showed that a high-expression level of BMP7 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that BMP7 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that a high-expression level of BMP7 serves as a biomarker for poor prognosis for HCC. Thus, we speculate that BMP7 may be a potential target of antiangiogenic therapy for HCC.

High expression of AP-4 predicts poor prognosis for hepatocellular carcinoma after curative hepatectomy

The aim of this study was to evaluate the association between activating enhancer binding protein 4 (AP-4) tissue expression and patient prognosis in hepatocellular carcinoma (HCC). The levels of AP-4 mRNA and protein in tumor and para-tumor tissue were evaluated in 30 HCC cases by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Additionally, AP-4 protein expression in 112 HCC was analyzed by immunohistochemistry. The correlation of AP-4 expression and patients' clinicopathological parameters was evaluated. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. By RT-PCR and Western blot, the levels of AP-4 mRNA and protein were significantly higher in HCC, compared to that in para-tumor tissue (p < 0.001). Immunohistochemical staining revealed that AP-4 was highly expressed in 53.6 % of the HCC patients. The AP-4 expression level was closely associated with serum alpha fetoprotein elevation, tumor size, histological differentiation, tumor recurrence, tumor metastasis, and tumor stage. Kaplan-Meier survival analysis showed that a high expression level of AP-4 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that AP-4 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that a high expression level of AP-4 serves as a biomarker for poor prognosis for HCC. Thus, we speculate that AP-4 may be a potential target of antiangiogenic therapy for HCC.

High ADAM8 expression is associated with poor prognosis in patients with hepatocellular carcinoma

In this study,we investigated the ADAM8 expression in hepatocellular carcinoma (HCC) and its correlation with clinicopathologic features,including the survival of patients with HCC. Furthermore,we examined the biological processes regulated by ADAM8 during the development of using HepG2 cell line as a model system. We used immunohistochemistry to compare ADAM8 protein expression in HCC and normal liver tissues and further analyze the ADAM8 protein expression in clinicopathologically characterized 105 HCC cases.We stably knocked down the endogenous expression level of ADAM8 in HepG2 cells with specific shRNA-expressing lentiviral vector. Following the successful establishment of stable cells,we examined in vitro cell growth by MTT assay,anchorage-independent growth by soft-agar colony formation assay and cell migration/invasion by transwell and boyden chamber assay. And in addition,we also investigated the in vivo tumor growth by xenograft transplantation of HepG2 cells into nude mice. Protein expression level of ADAM8 was markedly higher in HCC tissues than that in the normal liver tissues (P = 0.0058).In addition,high expression of ADAM8 protein was positively correlated with serum AFP elevation,tumor size,histological differentiation,tumor recurrence,tumor metastasis,and tumor stage. Patients with higher ADAM8 expression showed a significantly shorter overall survival time than patients with low ADAM8 expression. Multivariate analysis suggested that ADAM8 expression might be an independent prognostic indicator (p = 0.016) for the survival of patients with HCC. ADAM8-specific shRNA (shADAM8) successfully knocked down its endogenous expression in HepG2 cells. Compared to the parental and control shRNA-transfected (shCtrl) HepG2 cells,the shADAM8 cells exhibited significantly reduced in vitro cell growth,anchorage-independent growth,cell migration and invasion (p < 0.05).In vivo,the xenograft transplants from shADAM8 cells gave rise to much smaller tumors as compared to those from shCtrl cells. High ADAM8 expression is associated with poor overall survival in patients with HCC. Down-regulation of ADAM8 inhibits the growth,anchorage-independent growth,migration and invasion of HepG2 cells. ADAM8 may be a potential target of antiangiogenic therapy for HCC.

Expression of ADAM8 and its clinical values in diagnosis and prognosis of hepatocellular carcinoma

ADAM8 behaves as an active metalloprotease in vitro, hydrolyzing myelin basic protein and a variety of peptide substrates based on the cleavage sites of membrane-bound cytokines, growth factors, and receptors. Other studies have demonstrated overexpression of some ADAM family proteins in a variety of human tumors, but no report is available on the actual expression of ADAM8 and the correlation between clinicopathologic features and prognosis of hepatocellular carcinoma (HCC) patients. In this study, serum levels of ADAM8 were measured by ELISA in 126 patients with HCC, 50 patients with liver cirrhosis (LC), and 50 healthy individuals. The expression of ADAM8 in liver tissue was further studied using Western blotting in 126 patients with HCC and 50 with LC. The correlations between ADAM8 status and various clinicopathological parameters including survival were analyzed. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. The ELISA assay showed that the serum levels of ADAM8 in the HCC, LC, and healthy groups were 136.4 ± 34.5, 64.2 ± 20.1, and 63.2 ± 22.7 U/ml, respectively. Analysis of variance was used for inter-group comparison, and differences were found between the HCC group and the other two groups (both P < 0.001), while no difference was found between the LC group and the healthy group (P = 0.365). Western blotting assay showed that ADAM8 protein expression was detected in 62.7 % (79/126) HCC and in 32 % (16/50) LC tissues. Further, ADAM8 expression was associated closely with serum AFP elevation, tumor size, histological differentiation, tumor recurrence, tumor metastasis, and tumor stage. Kaplan-Meier survival analysis showed that patients with ADAM8-positive tumors had a shorter postoperative survival time than those with ADAM8-negative tumors (P < 0.001). Multivariate analysis revealed that ADAM8 expression was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that the expression of ADAM8 serves as a poor prognostic biomarker for HCC. ADAM8 may be a potential target of antiangiogenic therapy for HCC.

High expression of ADAM8 correlates with poor prognosis in hepatocellular carcinoma

OBJECTIVES

To evaluate the association between ADAM8 tissue expression and patient prognosis in hepatocellular carcinoma (HCC).

METHODS

ADAM8 expression was analyzed using immunohistochemical staining methods on tissue samples from a consecutive series of 105 HCC patients who underwent resections between 2000 and 2006. The correlation of ADAM8 expression and patients' clinicopathological parameters was evaluated. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model.

RESULTS

ADAM8 was highly expressed in 54.3% of the HCC patients. The ADAM8 expression level was closely associated with serum AFP elevation, tumor size, histological differentiation, tumor recurrence, tumor metastasis, and tumor stage. Kaplan-Meier survival analysis showed that a high expression level of ADAM8 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that ADAM8 expression level was an independent prognostic parameter for the overall survival rate of HCC patients.

CONCLUSIONS

These findings provide evidence that a high expression level of ADAM8 serves as a biomarker for poor prognosis for HCC. Thus, we speculate that ADAM8 may be a potential target of antiangiogenic therapy for HCC.

Prevention of hepatocellular carcinoma in nonviral-related liver diseases

Although chronic infection with hepatitis B virus and/or hepatitis C virus are the most important risk factors for hepatocellular carcinoma (HCC) worldwide, other causes of cirrhosis can also lead to HCC. Given the high prevalence of alcoholism and the worldwide obesity epidemic, the relevant importance of nonviral liver disease-related HCC is expected to increase in the future. Some evidence supports mechanistic interactions between host or environmental factors and chronic viral hepatitis in the development of HCC. For example, food- and water-borne carcinogens have contributed to unusually high rates of HCC in parts of China and sub-Saharan Africa. With some of these conditions, appropriate public health measures to reduce the population's exposure to known etiologic agents, or early therapeutic intervention for 'at-risk' individuals before development of cirrhosis (e.g. hereditary hemochromatosis) can prevent HCC. Community-based programs to discourage and deal with excessive alcohol intake, to promote tobacco smoking awareness, to avoid exposure to aflatoxin and other food toxins, and measures to reduce the pandemic of obesity and diabetes are vital for effective interruption of the rising tide of HCC from nonviral liver disease.