Molecular prognostication of liver cancer: end of the beginning

Mechanisms and therapeutic prospect of the JAK-STAT signaling pathway in liver cancer

Liver cancer (LC) poses a significant global health challenge due to its high incidence and poor prognosis. Current systemic treatment options, such as surgery, chemotherapy, radiofrequency ablation, and immunotherapy, have shown limited effectiveness for advanced LC patients. Moreover, owing to the heterogeneous nature of LC, it is crucial to uncover more in-depth pathogenic mechanisms and develop effective treatments to address the limitations of the existing therapeutic modalities. Increasing evidence has revealed the crucial role of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway in the pathogenesis of LC. The specific mechanisms driving the JAK-STAT pathway activation in LC, participate in a variety of malignant biological processes, including cell differentiation, evasion, anti-apoptosis, immune escape, and treatment resistance. Both preclinical and clinical investigations on the JAK-STAT pathway inhibitors have exhibited potential in LC treatment, thereby opening up avenues for the development of more targeted therapeutic strategies for LC. In this study, we provide an overview of the JAK-STAT pathway, delving into the composition, activation, and dynamic interplay within the pathway. Additionally, we focus on the molecular mechanisms driving the aberrant activation of the JAK-STAT pathway in LC. Furthermore, we summarize the latest advancements in targeting the JAK-STAT pathway for LC treatment. The insights presented in this review aim to underscore the necessity of research into the JAK-STAT signaling pathway as a promising avenue for LC therapy.

A Poly(amino acid)-Based Nanomedicine Strategy: Telomere-Telomerase Axis Targeting and Magnetic Resonance Imaging in Hepatocellular Carcinoma Treatment

Targeting telomere maintenance has emerged as a promising strategy for hepatocellular carcinoma (HCC) treatment. However, given the duality of the telomere-telomerase axis in telomere maintenance, a comprehensive strategy is urgently needed. Herein, we develop a poly(amino acid) (D-PAAs)-based strategy for spatiotemporal codelivery of telomerase inhibitor, BIBR1523, and AKT inhibitor, isobavachalcone. By leveraging D-PAAs' modifiability, we synthesize polymer-inhibitor conjugates (PB and PI) and a folic acid-decorated tumor-targeting vector (PF). These building blocks undergo micellization to fabricate a codelivery nanomedicine (P-BI@P-FA) by exploiting D-PAAs' noncovalent assembly. P-BI@P-FA improves the pharmacokinetics, tumor selectivity, and bioavailability of small molecule inhibitors and initiates a dual telomere-specific inhibition by combining telomerase deactivation with telomere disruption. Furthermore, a hybrid tumor-targeting magnetic nanosystem is designed using D-PAAs and manganese dioxide to showcase magnetic resonance imaging capacities. Our D-PAAs-based strategy addresses the pressing need for telomere-specific HCC treatment while allowing for diagnostic application, presenting a promising avenue for nanomedicine design.

Identification of an immune-related gene signature for predicting prognosis and immunotherapy efficacy in liver cancer via cell-cell communication

BACKGROUND

Liver cancer is one of the deadliest malignant tumors worldwide. Immunotherapy has provided hope to patients with advanced liver cancer, but only a small fraction of patients benefit from this treatment due to individual differences. Identifying immune-related gene signatures in liver cancer patients not only aids physicians in cancer diagnosis but also offers personalized treatment strategies, thereby improving patient survival rates. Although several methods have been developed to predict the prognosis and immunotherapeutic efficacy in patients with liver cancer, the impact of cell-cell interactions in the tumor microenvironment has not been adequately considered.

AIM

To identify immune-related gene signals for predicting liver cancer prognosis and immunotherapy efficacy.

METHODS

Cell grouping and cell-cell communication analysis were performed on single-cell RNA-sequencing data to identify highly active cell groups in immune-related pathways. Highly active immune cells were identified by intersecting the highly active cell groups with B cells and T cells. The significantly differentially expressed genes between highly active immune cells and other cells were subsequently selected as features, and a least absolute shrinkage and selection operator (LASSO) regression model was constructed to screen for diagnostic-related features. Fourteen genes that were selected more than 5 times in 10 LASSO regression experiments were included in a multivariable Cox regression model. Finally, 3 genes (stathmin 1, cofilin 1, and C-C chemokine ligand 5) significantly associated with survival were identified and used to construct an immune-related gene signature.

RESULTS

The immune-related gene signature composed of stathmin 1, cofilin 1, and C-C chemokine ligand 5 was identified through cell-cell communication. The effectiveness of the identified gene signature was validated based on experimental results of predictive immunotherapy response, tumor mutation burden analysis, immune cell infiltration analysis, survival analysis, and expression analysis.

CONCLUSION

The findings suggest that the identified gene signature may contribute to a deeper understanding of the activity patterns of immune cells in the liver tumor microenvironment, providing insights for personalized treatment strategies.

G6PD inhibits ferroptosis in hepatocellular carcinoma by targeting cytochrome P450 oxidoreductase

Ferroptosis is an important cell necrosis and has been a focus in cancer related research.Increcsing studies have focused on the phenotype and function of ferroptosis in tumorigenesis, but the underlying mechanism remains poorly understood. Here, we used bioinformatics approaches to identify differentially expressed genes associated with HCC and ferroptosis. We found that G6PD (glucose-6-phosphate dehydrogenase) was highly expressed in HCC and was associated with poor prognosis. G6PD promoted the proliferation, migration and invasion, as well as inhibited ferroptosis in HCC cells. Pathway and functional enrichment analyses revealed that G6PD was related to the P450 metabolic pathway. POR (cytochrome P450 oxidoreductase) was downregulated in HCC and was significantly correlated with the prognosis. G6PD inhibited ferroptosis inin HCC cells through POR. Knockdown of G6PD reduced the tumor volume and tumor weight in vivo. Our study demonstrated that G6PD deficiency suppresses cell growth, metastasis, and tumorigenesis via upregulating POR, suggesting that G6PD may be used as a biomarker for the treatment of HCC in the future.

Five-CpG-based prognostic signature for predicting survival in hepatocellular carcinoma patients

Objective:

Hepatocellular carcinoma (HCC) is a common malignancy associated with high morbidity and mortality rates worldwide. Early diagnosis plays an important role in the improvement of HCC prognosis.

Methods:

In this study, we conducted a comprehensive analysis of HCC DNA methylation and gene expression datasets in The Cancer Genome Atlas (TCGA), to identify a prognostic signature for HCC diagnosis and survival prediction. First, we identified differential methylation CpG (dmCpG) sites in HCC samples and compared them with those in adjacent normal liver tissues; this was followed by univariate analysis and Sure Independence Screening (SIS) in the training set. The robustness of the identified prognostic signature was evaluated using the testing set. To explore the biological processes involved in HCC progression, we also performed functional enrichment analysis for overlapping genes between genes containing dmCpG sites (DMGs) and differential expression genes (DEGs) in HCC patients, using data from the Database for Annotation, Visualization, and Integrated Discovery (DAVID).

Results:

As a result, we identified five CpG sites that were significantly associated with HCC survival through univariate analysis and SIS. Univariate analysis of clinical characteristics identified age and risk factors (including alcohol consumption and smoking) as independent factors that indicated HCC survival. Multivariate analysis indicated that the integrated prognostic signature (weighted combination of the five CpG sites) that took age and risk factors into consideration resulted in more accurate survival prediction.

Conclusions:

This study provides a novel signature for predicting HCC survival, and should be helpful for early HCC diagnosis and personalized treatment.

Early growth response 3 inhibits growth of hepatocellular carcinoma cells via upregulation of Fas ligand

Hepatocellular carcinoma (HCC) is a prevalent malignancy with aggressive biological behavior and poor prognosis. Early growth response 3 (EGR3) is a zinc finger transcription factor, and has been studied primarily in the context of neurodevelopment, autoimmunity, inflammation and angiogenesis. Accumulating evidence indicates that EGR3 is a novel suppressor gene of tumor initiation and progression in certain cancer events, but little work has been carried out in exploring the relationship between EGR3 and HCC growth. The purpose of this study was to investigate the possible effects of EGR3 on cell proliferation and apoptosis in HCC, and determine the underlying mechanisms. Here, we observed that EGR3 expression was frequently downregulated in HCC tissues and cell lines. Ectopic expression of EGR3 contributed to cell proliferation inhibition and apoptosis induction in HCC cells in vitro. Furthermore, the expression of Fas ligand (FasL) was significantly enhanced following upregulation of EGR3 in HCC cells, accompanied by an obvious increase of pro-apoptotic Bak and cell cycle inhibitor p21 expression. Based on nude mouse models, we demonstrated that ectopic expression of EGR3 markedly restricted tumor growth, and the expression of FasL was significantly increased in the xenograft tumor tissues which exhibited high EGR3 expression. We further established a co-transfection in HCC cells with EGR3 overexpression plasmid and FasL siRNA. We found that silencing of FasL gene impeded the anti-proliferative and pro-apoptotic effects, as well as the increase of Bak and p21 expression, suggesting an essential role of FasL in EGR3-mediated growth suppression in HCC cells. Collectively, in conclusion, EGR3 contributes to cell growth inhibition via upregulation of FasL in HCC.

Novel substituted aminothiazoles as potent and selective anti-hepatocellular carcinoma agents

Based on our previous identification of a disubstituted aminothiazole termed HBF-0079 with promising selective toxicity for HCC-derived cell lines versus non-HCC liver lines, a series of tri-substituted aminothiazole derivatives were prepared and evaluated. This work resulted in the discovery of isopropyl 4-(pyrazin-2-yl)-2-(pyrimidin-2-ylamino)thiazole-5-carboxylate, 14, which displayed EC50 value of 0.11μM and more than 450times of selectivity, and its methyl carbonate prodrug 24 with improved solubility in organic solvents. Furthermore, 14, was shown to reduce the proliferation of several liver cancer cells derived directly from patients.

Theaflavins suppress tumor growth and metastasis via the blockage of the STAT3 pathway in hepatocellular carcinoma

Theaflavins, the major black tea polyphenols, have been reported to exhibit promising antitumor activities in several human cancers. However, the role of theaflavins in hepatocellular carcinoma (HCC) is still unknown. In this study, we found that theaflavins could significantly inhibit proliferation, migration, and invasion, and induce apoptosis in HCC cells in vitro. Furthermore, we found that theaflavins inhibited the growth and metastasis of HCC in an orthotopic model and a lung metastasis model. Immunohistochemical analyses and terminal deoxynucleotidyl transferase dUTP nick end-labeling assays showed that theaflavins could suppress proliferation and induce apoptosis in vivo. Theaflavins also suppressed constitutive and inducible signal transducer and activator of transcription 3 (STAT3) phosphorylation. The downstream proteins regulated by STAT3, including the antiapoptotic proteins (Bcl-2 and Survivin) and the invasion-related proteins (MMP-2, MMP-9), were also downregulated after theaflavins treatment. Theaflavins induced apoptosis by activating the caspase pathway. Together, our results suggest that theaflavins suppress the growth and metastasis of human HCC through the blockage of the STAT3 pathway, and thus may act as potential therapeutic agents for HCC.

Critical role of DEK and its regulation in tumorigenesis and metastasis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality globally. Therefore, it is quite essential to identify novel HCC-related molecules for the discovery of new prognostic markers and therapeutic targets. As an oncogene, DEK plays an important role in cell processes and participates in a variety of cellular metabolic functions, and its altered expression is associated with several human malignancies. However, the functional significance of DEK and the involved complex biological events in HCC development and progression are poorly understood. Here, combing the results from clinical specimens and cultured cell lines, we uncover a critical oncogenic role of DEK, which is highly expressed in HCC cells. DEK protein encompasses two isoforms (isoforms 1 and 2) and isoform 1 is the most frequently expressed DEK isoform in HCC cells. DEK depletion by using shRNA inhibited the cell proliferation and migration in vitro and suppressed tumorigenesis and metastasis in mouse models. Consistently, DEK overexpression regardless of which isoform produced the opposite effects. Further studies showed that DEK induced cell proliferation through upregulating cell cycle related CDK signaling, and promoted cell migration and EMT, at least in part, through the repression of β-catenin/E-cadherin axis. Interestingly, isoform 1 induced cell proliferation more efficiently than isoform 2, however, no functional differences existed between these two isoforms in cell migration. Together, our study indicates that DEK expression is required for tumorigenesis and metastasis of HCC, providing molecular insights for DEK-related pathogenesis and a basis for developing new strategies against HCC.

Diagnostic Value of Preoperative Needle Biopsy for Tumor Grading Assessment in Hepatocellular Carcinoma

BACKGROUND

Needle core biopsy (NCB) is one of the most widely used and accepted methods for the diagnosis of focal hepatic lesions. Although many studies have assessed the diagnostic accuracy of NCB in predicting the tumor grade, it is still under debate.

OBJECTIVE

To identify the influence of number of biopsies on NCB diagnostic accuracy.

METHODS

153 patients with HCC were selected from patients who received preoperative NCB under the guidance of ultrasonography in our hospital. The diagnostic reference standard was the surgical pathologic diagnosis.

RESULTS

Using a 3-tier grading scheme (well, moderate and poor), the accuracy of NCB has no significant differences among different number of passes in HCC ≤5 cm. For HCC >5≤8 cm, the increasing number of passes could increase the diagnostic accuracy (63.3%, 81.8%, and 84.8% for passes one, two, and three, respectively). While in HCC>8 cm, the diagnostic accuracy of passes one, two, and three were 62.1%, 69%, and 75.8%, respectively.

CONCLUSIONS

The accuracy of NCB in assessing tumor grading associated with tumor size and number of passes. Meanwhile, a minimum of two passes should be performed to get better accuracy in patients with HCC >5 cm.

Biology of Hepatocellular Carcinoma

This chapter focuses on the identification of hepatocellular carcinoma (HCC) molecular signatures and the potentials of these signatures in prediction of HCC prognosis and driving of HCC therapeutic treatments. Progress in molecular profiling studies using DNA-microarray-based gene expression profiling has provided new insight about HCC pathogenesis, and gene signatures that can distinguish tumor subtypes assist clinical staging and predict patient outcomes. This provides the possibility to improve the stratification of HCC patients at a molecular level and, in the near future, will be potential in paving the way for tailored medicine in HCC patients.

Basal Autophagy and Feedback Activation of Akt Are Associated with Resistance to Metformin-Induced Inhibition of Hepatic Tumor Cell Growth

While accumulating evidence has shown that the use of the diabetic drug metformin may be beneficial against various tumors in some epidemiological studies, a few studies failed to show the same beneficial effects. The molecular and cellular mechanisms for these conflicting observations are not clear. In this study, we compared the inhibitory effects of cell growth by metformin on several hepatic tumor cell lines: SMMC-7721, HCC-97L, HCC-LM3 and HepG2. While metformin inhibited cell growth in all these cells, we found that SMMC-7721, HCC-97L and HCC-LM3 cells were more resistant than HepG2 cells. Mechanistically, we found that metformin inhibited mTOR in all these hepatic tumor cells. However, SMMC-7721 cells had higher levels of basal autophagy and mTORC2-mediated feedback activation of Akt than HepG2 cells, which may render SMMC-7721 cells to be more resistant to metformin-induced inhibition of cell growth. Similarly, HCC-97L and HCC-LM3 cells also had higher feedback activation of AKT than HepG2 cells, which may also account for their resistance to metformin-induced inhibition of cell growth. Therefore, the various basal autophagy and mTOR activity in different cancer cells may contribute to the controversial findings on the use of metformin in inhibition of cancers in humans.

Alteration of WWOX in human cancer: a clinical view

WWOX gene is located in FRA16D, the highly affected chromosomal fragile site. Its tumor suppressor activity has been proposed on a basis of numerous genomic alterations reported in chromosome 16q23.3-24.1 locus. WWOX is affected in many cancers, showing as high as 80% loss of heterozygosity in breast tumors. Unlike most tumor suppressors impairing of both alleles of WWOX is very rare. Despite cellular and animal models information on a WWOX role in cancer tissue is limited and sometimes confusing. This review summarizes information on WWOX in human tumors.

Genomic profiling of liver cancer

Development of liver cancers is driven largely by genomic alterations that deregulate signaling pathways, influencing growth and survival of cancer cells. Because of the hundreds or thousands of genomic/epigenomic alterations that have accumulated in the cancer genome, it is very challenging to find and test candidate genes driving tumor development and progression. Systematic studies of the liver cancer genome have become available in recent years. These studies have uncovered new potential driver genes, including those not previously known to be involved in the development of liver cancer. Novel approaches combining multiple datasets from patient tissues have created an unparalleled opportunity to uncover potential new therapeutic targets and prognostic/predictive biomarkers for personalized therapy that can improve clinical outcomes of the patients with liver cancer.

Deregulation of signalling pathways in prognostic subtypes of hepatocellular carcinoma: novel insights from interspecies comparison

Hepatocellular carcinoma is a frequent and fatal disease. Recent researches on rodent models and human hepatocarcinogenesis contributed to unravel the molecular mechanisms of hepatocellular carcinoma dedifferentiation and progression, and allowed the discovery of several alterations underlying the deregulation of cell cycle and signalling pathways. This review provides an interpretive analysis of the results of these studies. Mounting evidence emphasises the role of up-regulation of RAS/ERK, P13K/AKT, IKK/NF-kB, WNT, TGF-ß, NOTCH, Hedgehog, and Hippo signalling pathways as well as of aberrant proteasomal activity in hepatocarcinogenesis. Signalling deregulation often occurs in preneoplastic stages of rodent and human hepatocarcinogenesis and progressively increases in carcinomas, being most pronounced in more aggressive tumours. Numerous changes in signalling cascades are involved in the deregulation of carbohydrate, lipid, and methionine metabolism, which play a role in the maintenance of the transformed phenotype. Recent studies on the role of microRNAs in signalling deregulation, and on the interplay between signalling pathways led to crucial achievements in the knowledge of the network of signalling cascades, essential for the development of adjuvant therapies of liver cancer. Furthermore, the analysis of the mechanisms involved in signalling deregulation allowed the identification of numerous putative prognostic markers and novel therapeutic targets of specific hepatocellular carcinoma subtypes associated with different biologic and clinical features. This is of prime importance for the selection of patient subgroups that are most likely to obtain clinical benefit and, hence, for successful development of targeted therapies for liver cancer.

Targeting autophagy for the treatment of liver diseases

Autophagy is a lysosomal degradation pathway that can degrade bulk cytoplasm and superfluous or damaged organelles, such as mitochondria, to maintain cellular homeostasis. It is now known that dysregulation of autophagy can cause pathogenesis of numerous human diseases. Here, we discuss the critical roles that autophagy plays in the pathogenesis of liver diseases such as non-alcoholic and alcoholic fatty liver, drug-induced liver injury, protein aggregate-related liver diseases, viral hepatitis, fibrosis, aging and liver cancer. In particular, we discuss the emerging therapeutic potential by pharmacological modulation of autophagy for these liver diseases.

Essential metabolic, anti-inflammatory, and anti-tumorigenic functions of miR-122 in liver

miR-122, an abundant liver-specific microRNA (miRNA), regulates cholesterol metabolism and promotes hepatitis C virus (HCV) replication. Reduced miR-122 expression in hepatocellular carcinoma (HCC) correlates with metastasis and poor prognosis. Nevertheless, the consequences of sustained loss of function of miR-122 in vivo have not been determined. Here, we demonstrate that deletion of mouse Mir122 resulted in hepatosteatosis, hepatitis, and the development of tumors resembling HCC. These pathologic manifestations were associated with hyperactivity of oncogenic pathways and hepatic infiltration of inflammatory cells that produce pro-tumorigenic cytokines, including IL-6 and TNF. Moreover, delivery of miR-122 to a MYC-driven mouse model of HCC strongly inhibited tumorigenesis, further supporting the tumor suppressor activity of this miRNA. These findings reveal critical functions for miR-122 in the maintenance of liver homeostasis and have important therapeutic implications, including the potential utility of miR-122 delivery for selected patients with HCC and the need for careful monitoring of patients receiving miR-122 inhibition therapy for HCV.

Immunological and molecular correlates of disease recurrence after liver resection for hepatocellular carcinoma

The definition of the risk of hepatocellular carcinoma (HCC) recurrence after resection represents a central issue to improve the clinical management of patients. In this study we examined the prognostic relevance of infiltrating immune cell subsets in the tumor (TIL) and in nontumorous (NT) liver (LIL), and the expression of immune-related and lineage-specific mRNAs in HCC and NT liver derived from 42 patients. The phenotype of infiltrating cells was analyzed by flow cytometry, and mRNA expression in liver tissue was examined by real-time reverse transcription (RT)-PCR. The tumor immune microenvironment was enriched in inhibitory and dysfunctional cell subsets. Enrichment in CD4+ T-cells and in particular CD4 and CD8+ memory subsets within TIL was predictive of better overall survival (OS) and time to recurrence (TTR). Increased programmed death ligand 1 (PDL1) mRNA content and higher prevalence of invariant NKT (iNKT) cells were associated with shorter OS and TTR, respectively. By combined evaluation of infiltrating cell subsets along with mRNA profiling of immune and tumor related genes, we identified the intratumoral frequency of memory T-cells and iNKT-cells as well as PDL1 expression as the best predictors of clinical outcome. HCC infiltrate is characterized by the expression of molecules with negative regulatory function that may favor tumor recurrence and poor survival.

Systems biology approaches to decoding the genome of liver cancer

Molecular classification of cancers has been significantly improved patient outcomes through the implementation of treatment protocols tailored to the abnormalities present in each patient's cancer cells. Breast cancer represents the poster child with marked improvements in outcome occurring due to the implementation of targeted therapies for estrogen receptor or human epidermal growth factor receptor-2 positive breast cancers. Important subtypes with characteristic molecular features as potential therapeutic targets are likely to exist for all tumor lineages including hepatocellular carcinoma (HCC) but have yet to be discovered and validated as targets. Because each tumor accumulates hundreds or thousands of genomic and epigenetic alterations of critical genes, it is challenging to identify and validate candidate tumor aberrations as therapeutic targets or biomarkers that predict prognosis or response to therapy. Therefore, there is an urgent need to devise new experimental and analytical strategies to overcome this problem. Systems biology approaches integrating multiple data sets and technologies analyzing patient tissues holds great promise for the identification of novel therapeutic targets and linked predictive biomarkers allowing implementation of personalized medicine for HCC patients.

Construction of expression plasmids carrying miRNA targeting IGF-II and detection of their inhibitory effect on IGF-II expression in human HepG2 cells

AIM: To investigate inhibitory effect of transfection of eukaryotic expression plasmids carrying specific microRNA (miRNA) on insulin-like growth factor II (IGF-II) gene and protein expression in human HepG2 cells.

METHODS: Four miRNAs targeting the IGF-II gene were synthesized and inserted into the pcDNATM6.2-GW/EmGFPmiR vector. The recombinant plasmids were identified and transiently transfected into HepG2 cells. Their inhibitory efficiency on IGF-II expression was determined at gene level by real time-PCR and at protein level by ELISA.

RESULTS: Four eukaryotic expression plasmids carrying miRNA targeting IGF-II were constructed successfully and confirmed by sequencing. HepG2 cells were then transfected with these plasmids (MR-IGF-II-1 to 4). The highest transfection efficiency was up to 50%. The reduced rates of IGF-II gene expression were 33%, 43%, 0% and 3% in cells transfected with MR-IGF-II-1 to 4, respectively. Transfection of the MR-IGF-II-2 plasmid for 72 h reduced IGF-II protein expression by 44% in HepG2 cells.

CONCLUSION: The expression plasmids carrying miRNA targeting IGF-II have been successfully constructed. Transfection of these plamsids can efficiently inhibit IGF-II expression in HepG2 cells.

Detection of HCC-associated gene expression by real-time fluorescence quantitative PCR to establish a molecular diagnostic index for HCC

AIM: To develop a molecular diagnostic index for hepatocellular carcinoma (HCC).

METHODS: The expression of 11 genes was assessed by real-time fluorescent quantitative polymerase chain reaction (QRT-PCR) in 40 HCC specimens and matched tumor-adjacent specimens and surgical margin specimens, 10 cirrhotic tissue specimens, and 10 normal liver tissue specimens. Using G3PDH as a control, the 2-ΔΔCT method was used to calculate the relative gene expression levels. HCC-associated genes were then selected to establish a molecular diagnostic model for HCC.

RESULTS: Compared with normal liver tissue specimens, approximately 65.0%, 75.0%, and 67.5% of HCC specimens showed a >3-fold increase in the expression levels of tumor suppressor genes PRDM2, IGFBP3, and DLC-1, and approximately 87.5%, 77.5%, 82.5%, 85.0%, and 67.5% of HCC specimens showed a >3-fold decrease in the expression levels of oncogenes GPC3, STMN, CCNA2, BIRC5, and AFP, respectively. The expression levels of these eight genes differed significantly between HCC and cirrhotic tissue (0.45 ± 0.69 vs 0.50 ± 0.20; 0.17 ± 0.20 vs 0.67 ± 0.47; 0.29 ± 0.48 vs 0.58 ± 0.60; 677.57 ± 999.30 vs 4.41 ± 3.99; 17.56 ± 28.28 vs 1.17 ± 1.08; 53.17 ± 103.64 vs 2.09 ± 1.50; 16.53 ± 16.39 vs 1.82 ± 1.39; 4445.70 ± 11642.87 vs 0.86 ± 0.43, all P < 0.05). Molecular diagnostic index was estimated based on these eight genes, which was 2.2 ± 1.5, 3.0 ± 1.6, 2.9 ± 1.5, 6.3 ± 1.2 for liver cirrhosis, surgical margin, tumor-adjacent tissue, and cancer tissue, respectively. The molecular diagnostic index for cancer tissue was significantly different from those for liver cirrhosis, surgical margin, and tumor-adjacent tissue. When a molecular diagnostic index of 4 or greater was adopted to diagnose liver cancer using liver cirrhosis as a control, the sensitivity, specificity, and the area under the receiving operative curve (ROC) were 100%, 90%, and 0.995, respectively.

CONCLUSION: A molecular diagnostic index for HCC was successfully established using fluorescence quantitative PCR to detect HCC-associated genes.

Individualized medicine 2010

Molecular and cell biology have revolutionized not only diagnosis, therapy and prevention of human diseases but also greatly contributed to the understanding of their pathogenesis. Based on modern molecular and biochemical methods it is possible to identify on the one hand point mutations and single nucleotide polymorphisms. On the other hand, using high throughput array technologies, it is possible to analyse thousands of genes or gene products simultaneously, resulting in an individual gene or gene expression profile (signature). These data increasingly allow to define the individual risk for a given disease and to predict the individual prognosis of a disease as well as the efficacy of therapeutic strategies (individualized medicine). In the following sections some of the recent advances of predictive medicine and their clinical relevance will be addressed.

Pre-operative liver biopsy in cirrhotic patients with early hepatocellular carcinoma represents a safe and accurate diagnostic tool for tumour grading assessment

BACKGROUND & AIMS

Knowledge of pre-operative tumour grade is crucial in the management of hepatocellular carcinoma (HCC) because it can influence recurrence and survival after surgery. The accuracy of pre-operative needle core biopsy (NCB) in tumour grading has been assessed in only a few studies with conflicting results. Our aim was to determine the long-term safety and the overall accuracy of NCB in assessing tumour grading in subjects who had undergone liver resection for a single HCC.

METHODS

Eighty-one cirrhotic patients with HCC who had undergone NCB before liver resection were selected. Only patients with a single HCC and with at least a five-year-follow-up were included. Tumour grading was scored according to a modified Edmondson-Steiner classification: well/moderately (low grade) vs poorly-differentiated (high grade).

RESULTS

In the 81 patients with a solitary HCC (mean size 4.1 ± 2.3cm) tumour grade was correctly identified by NCB in 74 out of 81 (91.4%) HCCs. NCB overall sensitivity and specificity were 65% and 98.1%, respectively, with a PPV of 92% and an NPV of 91%. No major complications (in particular tumour seeding) were observed. The overall survival rates at 1, 3, and 5 years were 83%, 62%, and 44%, respectively; the recurrence rate after a 5-year-follow-up was 56.2% for low grade and 82.3% for high grade tumours (p<0.007).

CONCLUSIONS

Pre-operative NCB can be performed on early (<5 cm) HCC cirrhotic patients because it provides histologically useful information for HCC management with good accuracy and a low complication rate.

Suppression of signal transducer and activator of transcription 3 activation by butein inhibits growth of human hepatocellular carcinoma in vivo

PURPOSE

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the third cause of global cancer mortality. Increasing evidence suggest that STAT3 is a critical mediator of oncogenic signaling in HCC and controls the expression of several genes involved in proliferation, survival, metastasis, and angiogenesis. Thus, the novel agents that can suppress STAT3 activation have potential for both prevention and treatment of HCC.

EXPERIMENTAL DESIGN

The effect of butein on STAT3 activation, associated protein kinases, STAT3-regulated gene products, cellular proliferation, and apoptosis was investigated. The in vivo effect of butein on the growth of human HCC xenograft tumors in male athymic nu/nu mice was also examined.

RESULTS

We tested an agent, butein, for its ability to suppress STAT3 activation in HCC cells and nude mice model along with prospectively testing the hypothesis of STAT3 inhibition in a virtual predictive functional proteomics tumor pathway technology platform. We found that butein inhibited both constitutive and inducible STAT3 activation in HCC cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src and Janus-activated kinase 2. Butein inhibited proliferation and significantly potentiated the apoptotic effects of paclitaxel and doxorubicin in HCC cells. When administered intraperitoneally, butein inhibited the growth of human HCC xenograft tumors in male athymic nu/nu mice.

CONCLUSIONS

Overall, cumulative results from experimental and predictive studies suggest that butein exerts its antiproliferative and proapoptotic effects through suppression of STAT3 signaling in HCC both in vitro and in vivo.

Identification of beta-escin as a novel inhibitor of signal transducer and activator of transcription 3/Janus-activated kinase 2 signaling pathway that suppresses proliferation and induces apoptosis in human hepatocellular carcinoma cells

The activation of signal transducer and activator of transcription 3 (STAT3) has been linked with the proliferation, survival, invasion, and angiogenesis of a variety of human cancer cells, including hepatocellular carcinoma (HCC). Agents that can suppress STAT3 activation have potential for the prevention and treatment of HCC. In this study, we tested an agent, beta-escin, for its ability to suppress STAT3 activation. We found that beta-escin, a pentacyclic triterpenoid, inhibited both constitutive and interleukin-6-inducible STAT3 activation in a dose- and time-dependent manner in HCC cells. The suppression was mediated through the inhibition of activation of upstream kinases c-Src, Janus-activated kinase 1, and Janus-activated kinase 2. Vanadate treatment reversed the beta-escin-induced down-regulation of STAT3, suggesting the involvement of a tyrosine phosphatase. Indeed, we found that beta-escin induced the expression of tyrosine phosphatase Src homology phosphatase 1 that correlated with the down-regulation of constitutive STAT3 activation. beta-Escin also down-regulated the expression of STAT3-regulated gene products, such as cyclin D1, Bcl-2, Bcl-xL, survivin, Mcl-1, and vascular endothelial growth factor. Finally, beta-escin inhibited proliferation and also substantially potentiated the apoptotic effects of paclitaxel and doxorubicin in HCC cells. Overall, these results suggest that beta-escin is a novel blocker of STAT3 activation that may have potential in the suppression of proliferation and chemosensitization in HCC.

Gene systems network inferred from expression profiles in hepatocellular carcinogenesis by graphical Gaussian model

Hepatocellular carcinoma (HCC) in a liver with advanced-stage chronic hepatitis C (CHC) is induced by hepatitis C virus, which chronically infects about 170 million people worldwide. To elucidate the associations between gene groups in hepatocellular carcinogenesis, we analyzed the profiles of the genes characteristically expressed in the CHC and HCC cell stages by a statistical method for inferring the network between gene systems based on the graphical Gaussian model. A systematic evaluation of the inferred network in terms of the biological knowledge revealed that the inferred network was strongly involved in the known gene-gene interactions with high significance (P < 10(-4)), and that the clusters characterized by different cancer-related responses were associated with those of the gene groups related to metabolic pathways and morphological events. Although some relationships in the network remain to be interpreted, the analyses revealed a snapshot of the orchestrated expression of cancer-related groups and some pathways related with metabolisms and morphological events in hepatocellular carcinogenesis, and thus provide possible clues on the disease mechanism and insights that address the gap between molecular and clinical assessments.

Integrative and comparative genomics analysis of early hepatocellular carcinoma differentiated from liver regeneration in young and old

BACKGROUND

Hepatocellular carcinoma (HCC) is the third-leading cause of cancer-related deaths worldwide. It is often diagnosed at an advanced stage, and hence typically has a poor prognosis. To identify distinct molecular mechanisms for early HCC we developed a rat model of liver regeneration post-hepatectomy, as well as liver cells undergoing malignant transformation and compared them to normal liver using a microarray approach. Subsequently, we performed cross-species comparative analysis coupled with copy number alterations (CNA) of independent early human HCC microarray studies to facilitate the identification of critical regulatory modules conserved across species.

RESULTS

We identified 35 signature genes conserved across species, and shared among different types of early human HCCs. Over 70% of signature genes were cancer-related, and more than 50% of the conserved genes were mapped to human genomic CNA regions. Functional annotation revealed genes already implicated in HCC, as well as novel genes which were not previously reported in liver tumors. A subset of differentially expressed genes was validated using quantitative RT-PCR. Concordance was also confirmed for a significant number of genes and pathways in five independent validation microarray datasets. Our results indicated alterations in a number of cancer related pathways, including p53, p38 MAPK, ERK/MAPK, PI3K/AKT, and TGF-beta signaling pathways, and potential critical regulatory role of MYC, ERBB2, HNF4A, and SMAD3 for early HCC transformation.

CONCLUSIONS

The integrative analysis of transcriptional deregulation, genomic CNA and comparative cross species analysis brings new insights into the molecular profile of early hepatoma formation. This approach may lead to robust biomarkers for the detection of early human HCC.

Glutamine synthetase immunostaining correlates with pathologic features of hepatocellular carcinoma and better survival after radiofrequency thermal ablation

PURPOSE

Activation of the wnt pathway identifies a subgroup of hepatocellular carcinomas (HCC) with specific epidemiologic and genetic profiles. Wnt activation is predicted by mutation and/or nuclear translocation of beta-catenin and by glutamine synthetase (GS) immunoreactivity. We investigated whether GS staining associates with specific pathologic features of HCC and with survival after radiofrequency thermal ablation.

EXPERIMENTAL DESIGN

Monoistitutional retrospective-prospective study in a tertiary hospital setting. Two hundred and seven cirrhotics (mean age, 70 years; 63% males, 82.1% hepatitis C virus positive) with early HCC were consecutively treated with radiofrequency thermal ablation (RFTA). Mean tumor size was 2.7 cm; 20.3% of patients had multiple nodules; and median follow-up was 36 months with 54.6% overall mortality. Tumor samples were mainly obtained by biopsy (92,5%) and examined by H&E and immunostaining for beta-catenin and GS. Main outcome measures were overall and tumor-specific mortality by Kaplan-Meier analysis and Cox proportional hazard models corrected for competing risks.

RESULTS

Ninety-one patients (43.9%) had GS-positive HCCs by immunostaining. These tumors had larger size (P = 0.012) and characteristic histology (low grade, pseudoacini, hydropic changes, bile staining, lack of steatosis, and fibrosis). Other clinical or treatment variables were similar between groups. Variables correlating with tumor-specific and overall mortality by univariate analysis were tumor recurrence, advanced disease, posttreatment alpha-fetoprotein levels, and GS staining. Yearly, overall mortality rate was lower in GS-positive patients (12.4 versus 20% yearly; P = 0.006). By multivariate analysis, GS immunostaining correlated with reduced specific (hazard ratio, 0.58; 95% confidence interval, 0.34-0.97) and overall mortality (hazard ratio, 0.62; 95% confidence interval, 0.40-0.96).

CONCLUSIONS

Standard histology and GS status identify a HCC subset with distinct clinical and pathologic features.

Antitumor activity of type I and type III interferons in BNL hepatoma model

Hepatocellular carcinoma (HCC) occurs most commonly secondary to cirrhosis due to chronic hepatitis C or B virus (HCV/HBV) infections. Type I interferon (IFN-alpha) treatment of chronic HCV/HBV infections reduces the incidence of HCC in cirrhotic patients. However, IFN-alpha toxicity limits its tolerability and efficacy highlighting a need for better therapeutic treatments. A recently discovered type III IFN (IFN-lambda) has been shown to possess antiviral properties against HCV and HBV in vitro. In phase I clinical trials, IFN-lambda treatment did not cause significant adverse reactions. Using a gene therapy approach, we compared the antitumor properties of IFN-alpha and IFN-lambda in a transplantable hepatoma model of HCC. BALB/c mice were inoculated with syngeneic BNL hepatoma cells, or BNL cells expressing IFN-lambda (BNL.IFN-lambda cells) or IFN-alpha (BNL.IFN-alpha cells). Despite the lack of antiproliferative activity of IFNs on BNL cells, both BNL.IFN-lambda and BNL.IFN-alpha cells displayed retarded growth kinetics in vivo. Depletion of NK cells from splenocytes inhibited splenocyte-mediated cytotoxicity, demonstrating that NK cells play a role in IFN-induced antitumor responses. However, isolated NK cells did not respond directly to IFN-lambda. There was also a marked NK cell infiltration in IFN-lambda producing tumors. In addition, IFN-lambda and, to a lesser extent, IFN-alpha enhanced immunocytotoxicity of splenocytes primed with irradiated BNL cells. Splenocyte cytotoxicity against BNL cells was dependent on IL-12 and IFN-gamma, and mediated by dendritic cells. In contrast to NK cells, isolated from spleen CD11c+ and mPDCA+ dendritic cells responded directly to IFN-lambda. The antitumor activities of IFN-lambda against hepatoma, in combination with HCV and HBV antiviral activities warrant further investigation into the clinical use of IFN-lambda to prevent HCC in HCV/HBV-infected cirrhotic patients, as well as to treat liver cancer.

CpG island methylator phenotype associated with tumor recurrence in tumor-node-metastasis stage I hepatocellular carcinoma

BACKGROUND

CpG island methylator phenotype (CIMP), characterized by simultaneous methylation of multiple tumor suppressor genes (TSGs), has been reported to be associated with biological malignancy in many cancers. Whether CIMP is potentially predictive of clinical outcome in hepatocellular carcinoma (HCC) remains unknown.

METHODS

We investigated the methylation status of ten TSGs and CIMP in 115 samples of HCC and 48 samples of corresponding nonneoplastic liver tissues using a methylation-specific polymerase chain reaction.

RESULTS

The methylation frequencies of the ten genes examined in HCC were 40.0% for p14 ( ARF ), 60.9% for p15 ( INK4b ), 70.4% for p16 ( INK4a ), 34.8% for p73, 70.4% for GSTP1, 64.3% for MGMT, 13.0% for hMLH1, 59.1% for RARbeta, 82.6% for SOCS-1, and 80.9% for OPCML. CIMP+ (with six or more methylated genes) was detected in 68 (59.1%) of 115 HCCs and none of 48 nonneoplastic liver tissues. On stratified univariate analysis, patients with tumor-node-metastasis (TNM) stage I HCC with CIMP+ had significantly shorter overall survival (OS) (P = 0.002) and recurrence-free survival (RFS) (P = 0.042) than those with CIMP-. Furthermore, multivariate analysis revealed CIMP+ as an independent prognostic factor for both OS [hazard ratio (HR), 12.266; P = 0.015] and RFS (HR, 2.275; P = 0.032) in TNM stage I patients.

CONCLUSIONS

CIMP+ may specifically define a subgroup of patients with unfavorable outcome in TNM stage I HCC. Examination of CIMP status may be useful for stratifying prognosis of patients with early-stage HCC and identifying patients who are at higher risk for recurrence.

Identification of S100A8-correlated genes for prediction of disease progression in non-muscle invasive bladder cancer

Background

S100 calcium binding protein A8 (S100A8) has been implicated as a prognostic indicator in several types of cancer. However, previous studies are limited in their ability to predict the clinical behavior of the cancer. Here, we sought to identify a molecular signature based on S100A8 expression and to assess its usefulness as a prognostic indicator of disease progression in non-muscle invasive bladder cancer (NMIBC).

Methods

We used 103 primary NMIBC specimens for microarray gene expression profiling. The median follow-up period for all patients was 57.6 months (range: 3.2 to 137.0 months). Various statistical methods, including the leave-one-out cross validation method, were applied to identify a gene expression signature able to predict the likelihood of progression. The prognostic value of the gene expression signature was validated in an independent cohort (n = 302).

Results

Kaplan-Meier estimates revealed significant differences in disease progression associated with the expression signature of S100A8-correlated genes (log-rank test, P < 0.001). Multivariate Cox regression analysis revealed that the expression signature of S100A8-correlated genes was a strong predictor of disease progression (hazard ratio = 15.225, 95% confidence interval = 1.746 to 133.52, P = 0.014). We validated our results in an independent cohort and confirmed that this signature produced consistent prediction patterns. Finally, gene network analyses of the signature revealed that S100A8, IL1B, and S100A9 could be important mediators of the progression of NMIBC.

Conclusions

The prognostic molecular signature defined by S100A8-correlated genes represents a promising diagnostic tool for the identification of NMIBC patients that have a high risk of progression to muscle invasive bladder cancer.

DNA methylation changes in normal liver tissues and hepatocellular carcinoma with different viral infection

Hepatocellular carcinoma (HCC) is known to be associated with both HBV and HCV. While epigenetic changes have been previously reported to be associated with hepatocellular carcinoma (HCC), whether the epigenetic profile of HBC associated HCC differs from that of HCV-associated HCC is unclear. We analyzed DNA methylation of ten genes (APC, CCND2, CDKN2A, GSTP1, HOXA9, RARB, RASSF1, RUNX, SFRP1, and TWIST1) using MethyLight assays on 65 archived liver tissue blocks. Three genes (APC, CCND2, and GSTP1) were frequently methylated in normal liver tissues. Five genes (APC, CDKN2A, HOXA9, RASSF1, and RUNX) were significantly more frequently methylated in malignant liver tissues than normal liver tissues. Among HCC cases, HOXA9, RASSF1 and SFRP1 were methylated more frequently in HBV-positive HCC cases, while CDKN2A were significantly more frequently methylated in HCV-positive HCC cases. Our data support the hypothesis that HCC resulting from different viral etiologies is associated with different epigenetic changes.

Current advances in tumor proteomics and candidate biomarkers for hepatic cancer

Tumor proteomics apply proteomics techniques to tumor biological research, mainly by screening candidate biomarkers for early tumor diagnosis, prognosis and treatment. Hepatocellular carcinoma (HCC) is a type of malignant tumor with one of the highest death rates in the world. With the advent of the post-genomic age, tumor biological research developing the technology of proteomics has become a major focus of researchers. The discovery of novel candidate biomarkers is one of crucial problems for the early diagnosis of HCC. In general, there are three distinct types of candidate biomarkers for HCC based on different areas: biochemical biomarkers, antigenic biomarkers and epigenetic biomarkers. This review mainly discusses current advances in the problems and prospects of candidate biomarker for the early diagnosis of HCC, discovered by technologies of tumor proteomics.

Prognostic significance of the DNA-index in liver transplantation for hepatocellular carcinoma in cirrhosis

OBJECTIVE

This study was conducted to evaluate the prognostic significance of the tumor DNA index in patients receiving liver transplantation for hepatocellular carcinoma (HCC) in cirrhosis.

BACKGROUND

In patients suffering from HCC in cirrhosis, the current selection for liver transplantation does not optimally achieve the goal to simultaneously maximize the number of viable transplant candidates and reject the smallest number of those who could have benefited. This is the first report on the prognostic significance of the tumor DNA index.

PATIENTS AND METHODS

From 1988 to 2007, liver transplantation for HCC in cirrhosis was performed in 246 consecutive patients. The DNA-index was determined by Feulgen staining and semiautomatical image analysis. Interpretation of DNA histograms followed the recommendations outlined in the European Society for Analytical Cellular Pathology consensus report on diagnostic DNA image cytometry.

RESULTS

A DNA-index <or=1.5 was detected in the HCC of 159 patients (65%). Five- and 10-year post-transplant survival rates in this group were 86% and 80%, respectively. The DNA-index exceeded 1.5 in 87 patients (35%). These patients had 5- and 10-year survival rates of 27% and 6%, respectively, which were significantly lower than in the DNA-index <or=1.5 group (P < 0.0001). On univariate analysis, DNA-index, vascular invasion, fulfillment of the Milan criteria, and histopathological grading were prognostic parameters. In the multivariate analysis, only DNA-index (odds ratio: 11.9; 95% confidence interval: 7.1-20.0; P < 0.0001) and vascular infiltration (odds ratio: 1.7; 95% confidence interval: 1.1-2.6; P < 0.01) were identified as prognostic variables.

CONCLUSION

This is the first study to describe the DNA-index as a strong prognostic indicator after liver transplantation for HCC in cirrhosis. At this time, determination of the DNA-index is likely to be the most promising diagnostic tool in the selection of transplant candidates.

Bead-based microarray analysis of microRNA expression in hepatocellular carcinoma: miR-338 is downregulated

AIM

Recent studies have underlined causative links between microRNA (miRNA) deregulation and cancer development. However, the relevance of abnormally expressed miRNA to tumor biology has not been well understood in hepatocellular carcinoma (HCC).

METHODS

A bead-based miRNA expression profiling method was performed on 20 pairs of surgically removed HCC and adjacent non-tumorous tissue (NT). Special miR-338 downregulations and miR-338 associated with clinical characteristics was validated in an extended samples set of 36 paired HCC and adjacent non-tumorous liver tissues by real-time reverse transcription polymerase chain reaction (RT-PCR) analysis.

RESULTS

Out of our bead-based microarray data, 12 upregulated and 19 downregulated miRNA were found to be associated with HCC. Further characterization of miRNA-338, in which 20 pairs of the samples were clustered clearly into two groups according to expression of miR-338, revealed that the level of miR-338 expression can be associated with clinical aggressiveness, such as, tumor size, tumor-node-metastasis stage, vascular invasion and intrahepatic metastasis. These results were validated by real-time RT-PCR analysis.

CONCLUSION

Our study suggests that miRNA expression could have relevance to the clinical behavior of HCC and that the bead-based miRNA expression profiling method might be a suitable system to assay miRNA expression in large-scale diagnostic trails.

Alterations of gene expression of RB pathway in Opisthorchis viverrini infection-induced cholangiocarcinoma

Opisthorchiasis has the significant relationship with the high prevalence of cholangiocarcinoma (CCA; a bile duct cancer) in the endemic areas in Southeast Asia. To reveal the molecular mechanism of the tumorigenesis induced by Opisthorchis viverrini infection, the present study investigated the kinetic expression of RB pathway genes, including RB1, p16(INK4), cyclin D1, and CDK4, during the development of opisthorchiasis-associated CCA in hamster model. The results of quantitative real-time polymerase chain reaction indicated that the expressions of RB1 and p16(INK4) were down-regulated during the development of CCA induced by infection plus N-nitrosodimethylamine treatment in a time-dependent manner. On the other hand, the expressions of cyclin D1 and CDK4 were up-regulated. The expression kinetics was corresponding to the pathological progression of the opisthorchiasis-associated CCA, revealed by histopathological observation. Moreover, the analysis of the expression of these genes in human opisthorchiasis-associated CCA cases showed the decreased expression of RB1 and p16(INK4) in 50% and 82.7% cases and overexpression of cyclin D1 and CDK4 in half cases, respectively. The results suggested that RB pathway is likely involved in the tumorigenesis of opisthorchiasis-induced CCA and proposed the potential application of some of these genes as biomarkers in predispose and molecular therapy of the parasite-associated cancer.

Transient and etiology-related transcription regulation in cirrhosis prior to hepatocellular carcinoma occurrence

AIM: To search for transcription dysregulation that could (1) differentiate hepatocellular carcinoma (HCC)-free from HCC-related cirrhosis (2) differentiate HCC-free cirrhosis related to HCV from that related to alcohol intake.

METHODS: Using microarray analysis, we compared transcript levels in HCC-free cirrhosis (alcoholism: 7; hepatitis C: 7), HCC-associated cirrhosis (alcoholism: 10; hepatitis C: 10) and eight control livers. The identified transcripts were validated by qRT-PCR in an independent cohort of 45 samples (20 HCC-free cirrhosis; 15 HCC-associated cirrhosis and 10 control livers). We also confirmed our results by immunohistochemistry.

RESULTS: In HCC-free livers, we identified 70 transcripts which differentiated between alcoholic-related cirrhosis, HCV-related cirrhosis and control livers. They mainly corresponded to down-regulation. Dysregulation of Signal Transduction and Activator of Transcription-3 (STAT-3) was found along with related changes in STAT-3 targets which occurred in an etiology-dependent fashion in HCC-free cirrhosis. In contrast, in HCC, such transcription dysregulations were not observed.

CONCLUSION: We report that transcriptional dysregulations exist in HCC-free cirrhosis, are transiently observed prior to detectable HCC onset and may be appear like markers from cirrhosis to HCC transition.

Tailoring to RB: tumour suppressor status and therapeutic response

The retinoblastoma tumour suppressor (RB) is a crucial regulator of cell-cycle progression that is invoked in response to a myriad of anti-mitogenic signals. It has been hypothesized that perturbations of the RB pathway confer a synonymous proliferative advantage to tumour cells; however, recent findings demonstrate context-specific outcomes associated with such lesions. Particularly, loss of RB function is associated with differential response to wide-ranging therapeutic agents. Thus, the status of this tumour suppressor may be particularly informative in directing treatment regimens.

Expression and dynamic alteration of hepatoma-related growth factors during malignant transformation of hepatocytes

Hepatocellular carcinoma (HCC) is a common hepatic malignancy worldwide. Its nature of rapid growth results in a grave prognosis. Its treatment is challenging because the mechanisms underlying tumor progression are still largely unknown. Recently, new molecular targets have been confirmed and various targeted agents are now being investigated for the treatment of HCC. The progression of HCC is closely associated with expression of hepatic growth factors that may be molecular targets for HCC treatment. This paper concludes the expression characters and dynamic changes of several hepatoma-related growth factors such as IGF-Ⅱ, VEGF, TGF-β1 and HGF.

Linking molecular classification of hepatocellular carcinoma and personalized medicine: preliminary steps

PURPOSE OF REVIEW

The development of high-throughput technologies able to simultaneously investigate thousands of genes (e.g. single nucleotide polymorphism-array, gene expression microarray, etc.) has opened a new era in translational research. Obtaining a molecular classification of hepatocellular carcinoma, however, remains a striking challenge. This review summarizes the molecular classifications of hepatocellular carcinoma reported so far, analyzes the status of targeted therapies tested in clinical trials, and evaluates feasibility of personalized medicine approaches in hepatocellular carcinoma.

RECENT FINDINGS

Different investigators attempted to classify patients according to their liver cancer molecular background, a feature that will path the way for trial enrichment and personalized medicine. Currently, hepatocellular carcinoma can be classified in molecular classes according to Wnt-beta-catenin pathway activation, proliferation signature activation (associated with chromosomal instability), and other subgroups. In parallel, the first-time-ever positive results of a phase III trial in advanced hepatocellular carcinoma with the multikinase inhibitor sorafenib have encouraged this approach.

SUMMARY

Selection of patient candidates according to their tumor molecular background is a reality in human malignancies. Thus, a molecular classification is essential to allow the development of new targets, and to customize therapies in patients with hepatocellular carcinoma.

Genome-wide differences in hepatitis C- vs alcoholism-associated hepatocellular carcinoma

AIM

To look at a comprehensive picture of etiology-dependent gene abnormalities in hepatocellular carcinoma in Western Europe.

METHODS

With a liver-oriented microarray, transcript levels were compared in nodules and cirrhosis from a training set of patients with hepatocellular carcinoma (alcoholism, 12; hepatitis C, 10) and 5 controls. Loose or tight selection of informative transcripts with an abnormal abundance was statistically valid and the tightly selected transcripts were next quantified by qRTPCR in the nodules from our training set (12 + 10) and a test set (6 + 7).

RESULTS

A selection of 475 transcripts pointed to significant gene over-representation on chromosome 8 (alcoholism) or -2 (hepatitis C) and ontology indicated a predominant inflammatory response (alcoholism) or changes in cell cycle regulation, transcription factors and interferon responsiveness (hepatitis C). A stringent selection of 23 transcripts whose differences between etiologies were significant in nodules but not in cirrhotic tissue indicated that the above dysregulations take place in tumor but not in the surrounding cirrhosis. These 23 transcripts separated our test set according to etiologies. The inflammation-associated transcripts pointed to limited alterations of free iron metabolism in alcoholic vs hepatitis C tumors.

CONCLUSION

Etiology-specific abnormalities (chromo-some preference; differences in transcriptomes and related functions) have been identified in hepatocellular carcinoma driven by alcoholism or hepatitis C. This may open novel avenues for differential therapies in this disease.

Specific diagnosis of gamma-glutamyl transferase subfraction and its genotyping for hepatocellular carcinoma

Abnormal expression of total γ-glutamyl transferase (GGT, EC 2.3.2.2) activity can be found in patients with different liver diseases and extrahepatic tumors. Circulating GGT from hepatocellular carcinoma (HCC) patients can be divided into different isoforms (Ⅰ, Ⅰ', Ⅱ, Ⅱ', β, δ, ε, φA, ⅦB, φC, γA, γB) by using PAGE. Some of these isoforms (Ⅰ', Ⅱ and Ⅱ', and hepatoma-specific GGT, HS-GGT) can be detected in sera of HCC patients. Hepatic GGT gene expression may be closely related to the development of HCC. The human cDNA sequences from fetal liver, placenta and HepG2 cells (H) were investigated. The genotype H was predominant in cancerous tissues of HCC. Both HS-GGT and genotype H were confirmed as useful specific HCC markers, with higher specificity and sensitivity, and their analysis may be useful for HCC diagnosis and differentiation.

Biología celular y genética en el cáncer de hígado

Hepatocellular carcinoma (HCC) is the main cause of death in cirrhotic patients and has become a major health problem in developed countries. Analysis of the somatic alterations and gene expression profiles in patients with HCC have provided important information the genes involved in liver carcinogenesis. Nevertheless, the most important molecular alterations in the initial stages of the disease are currently unknown. The application of high resolution technologies to other forms of cancer (genome analysis with oligo microarrays and SNP arrays) should lead to greater insight into the pathogenesis of this neoplasm. In the last few years, distinct signaling pathways involved in hepatocarcinogenesis have been identified. Among these, the Wnt, EGFR and PI3k/akt/mTOR pathways are constitutively altered in numerous studies, providing the molecular basis for the molecular treatment of this tumor. As in other neoplasms, the original tumor cell in HCC is controversial. The most widely accepted hypothesis suggests that numerous genomic alterations in the hepatocyte cells lead to a neoplastic phenotype. Alternatively, it has been postulated that at least a subgroup of tumors could be of stem cell origin. Both hypotheses agree on the existence of cancer stem cells, arising from the original tumor cell; these cancer stem cells would then perpetuate and disseminate the neoplasm. This review summarizes the most important information on the structural and functional alterations in HCC and describes some of the main signaling pathways implicated in liver cancer.

Genes Associated With Progression and Recurrence of Hepatocellular Carcinoma in Hepatitis C Patients Waiting and Undergoing Liver Transplantation: Preliminary Results

BACKGROUND

Liver transplantation (LT) represents a curative treatment for small hepatocellular carcinoma (HCC). Potentially curable higher-stage HCC patients are denied LT due to the lack of cancer markers that predict progression and recurrence.

METHODS

Thirty-eight candidates for LT with hepatitis C virus (HCV) cirrhosis and HCC were studied. Gene expression (Gexp) analysis of tumor samples was performed using microarrays.

RESULTS

Twenty patients underwent transplantation, 13 progressed while waiting for transplantation, 4 are alive awaiting transplantation, and 1 died without progression while waiting for LT. Differences in GExp among patients who underwent LT or did not progress (n=25) versus those whose disease progressed while waiting for LT (n=13) were assessed. Thus, 54 probe sets (Pset) were significantly differentially expressed. Among LT patients, 10 Psets were differentially expressed between LT patients with the same explanted stage that recurred (n=5) versus LT patients who did not recur (n=5). Ninety-eight Psets were significantly associated with survival at the alpha=0.005 level.

CONCLUSIONS

Here, we have identified genes associated with HCC progression in HCV-HCC patients awaiting LT transplantation. A limited number of genes were related to overall survival and cancer-free survival after LT. Incorporation of these molecular markers could help to improve organ allocation for HCV-HCC patients.

Genome-wide molecular profiles of HCV-induced dysplasia and hepatocellular carcinoma

Although HCC is the third-leading cause of cancer-related deaths worldwide, there is only an elemental understanding of its molecular pathogenesis. In western countries, HCV infection is the main etiology underlying this cancer's accelerating incidence. To characterize the molecular events of the hepatocarcinogenic process, and to identify new biomarkers for early HCC, the gene expression profiles of 75 tissue samples were analyzed representing the stepwise carcinogenic process from preneoplastic lesions (cirrhosis and dysplasia) to HCC, including 4 neoplastic stages (very early HCC to metastatic tumors) from patients with HCV infection. We identified gene signatures that accurately reflect the pathological progression of disease at each stage. Eight genes distinguish between control and cirrhosis, 24 between cirrhosis and dysplasia, 93 between dysplasia and early HCC, and 9 between early and advanced HCC. Using quantitative real-time reverse-transcription PCR, we validated several novel molecular tissue markers for early HCC diagnosis, specifically induction of abnormal spindle-like, microcephaly-associated protein, hyaluronan-mediated motility receptor, primase 1, erythropoietin, and neuregulin 1. In addition, pathway analysis revealed dysregulation of the Notch and Toll-like receptor pathways in cirrhosis, followed by deregulation of several components of the Jak/STAT pathway in early carcinogenesis, then upregulation of genes involved in DNA replication and repair and cell cycle in late cancerous stages.

CONCLUSION

These findings provide a comprehensive molecular portrait of genomic changes in progressive HCV-related HCC.

Molecular pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common life-threatening malignancies in the world. This cancer generally arises within the boundaries of well-defined causal factors, of which viral hepatitis infection, aflatoxin exposure, chronic alcohol abuse, and nonalcoholic steatohepatitis are the major risk factors. Despite the identification of these etiological agents, hepatocarcinogenesis remains poorly understood. The molecular mechanisms leading to the development of HCC appear extremely complex and only recently have begun to be elucidated. Currently, surgical resection or liver transplantation offer the best chance of cure for the patient with HCC; however, these therapies are hindered by inability of many of these patients to undergo liver resection, by tumor recurrence and by donor shortages. A lack of suitable therapeutic strategies has led to a greater focus on prevention of HCC using antiviral agents and vaccination. Overall, the current outlook for patients with HCC is bleak; however, a better understanding of the molecular and genetic basis of this cancer should lead to the development of more efficacious therapies.