Expressions of basic fibroblast growth factor and its receptors and their relationship to proliferation of human hepatocellular carcinoma cell lines

Heparanase is a prognostic biomarker independent of tumor purity and hypoxia based on bioinformatics and immunohistochemistry analysis of esophageal squamous cell carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive tract with a poor prognosis. The tumor microenvironment (TME) is mainly composed of tumor cells, stromal cells, and immune cells and plays an important role in ESCC development. There are substantial differences in tumor purity among different parts of ESCC tissues, consisting of distinct immune and stromal cells and variations in the status of hypoxia. Thus, prognostic models of ESCC based on bioinformatic analysis of tumor tissues are unreliable.

Method

Differentially expressed genes (DEGs) independent of tumor purity and hypoxia were screened by Spearman correlation analysis of public ESCC cohorts. Subsequently, the DEGs were subjected to Cox regression analysis. Then, we constructed a protein–protein interaction (PPI) network of the DEGs using Cytoscape. Intersection analysis of the univariate Cox and PPI results indicated that heparanase (HPSE), an endo-β-D-glucuronidase capable of cleaving heparan sulfate side chains, was a predictive factor. Gene set enrichment analysis (GSEA) was used to reveal the potential function of HPSE, and single-cell sequencing data were analyzed to evaluate the distribution of HPSE in immune cells. Furthermore, a human ESCC tissue microarray was used to validate the expression and prognostic value of HPSE.

Result

We found that HPSE was downregulated in ESCC tissues and was not correlated with tumor purity or hypoxia status. HPSE is involved in multiple biological processes. ESCC patients with low HPSE expression in cancerous tissues exhibited poor prognosis.

Conclusions

These results indicate that low HPSE expression in cancerous tissues correlates with poor prognosis in patients with ESCC. HPSE is a novel prognostic biomarker independent of tumor purity and hypoxia status in ESCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02698-9.

ONECUT2 facilitates hepatocellular carcinoma metastasis by transcriptionally upregulating FGF2 and ACLY

Metastasis is the predominant reason for high mortality of hepatocellular carcinoma (HCC) patients. It is critical to explore the molecular mechanism underlying HCC metastasis. Here, we reported that transcription factor One Cut homeobox 2 (ONECUT2) functioned as an oncogene to facilitate HCC metastasis. Elevated ONECUT2 expression was positively correlated with increased tumor number, tumor encapsulation loss, microvascular invasion, poor tumor differentiation, and advanced TNM stage. Mechanistically, ONECUT2 directly bound to the promoters of fibroblast growth factor 2 (FGF2) and ATP citrate lyase (ACLY) and transcriptionally upregulated their expression. Knockdown of FGF2 and ACLY inhibited ONECUT2-mediated HCC metastasis, whereas upregulation of FGF2 and ACLY rescued ONECUT2 knockdown-induced suppression of HCC metastasis. ONECUT2 expression was positively correlated with FGF2 and ACLY expression in human HCC tissues. HCC patients with positive coexpression of ONECUT2/FGF2 or ONECUT2/ACLY exhibited the worst prognosis. In addition, FGF2 upregulated ONECUT2 expression through the FGFR1/ERK/ELK1 pathway, which formed an FGF2-FGFR1-ONECUT2 positive feedback loop. Knockdown of ONECUT2 inhibited FGF2-induced HCC metastasis. Furthermore, the combination of FGFR1 inhibitor PD173074 with ACLY inhibitor ETC-1002 markedly suppressed ONECUT2-mediated HCC metastasis. In summary, ONECUT2 was a potential prognostic biomarker in HCC and targeting this oncogenic signaling pathway may provide an efficient therapeutic strategy against HCC metastasis.

Bevacizumab Augments the Antitumor Efficacy of Infigratinib in Hepatocellular Carcinoma

The fibroblast growth factor (FGF) signaling cascade is one of the key signaling pathways in hepatocellular carcinoma (HCC). FGF has been shown to augment vascular endothelial growth factor (VEGF)-mediated HCC development and angiogenesis, as well as to potentially lead to resistance to VEGF/VEGF receptor (VEGFR)-targeted agents. Thus, novel agents targeting FGF/FGF receptor (FGFR) signaling may enhance and/or overcome de novo or acquired resistance to VEGF-targeted agents in HCC. Mice bearing high- and low-FGFR tumors were treated with Infigratinib (i.e., a pan-FGFR kinase inhibitor) and/or Bevacizumab (i.e., an angiogenesis inhibitor). The antitumor activity of both agents was assessed individually or in combination. Tumor vasculature, intratumoral hypoxia, and downstream targets of FGFR signaling pathways were also investigated. Infigratinib, when combined with Bevacizumab, exerted a synergistic inhibitory effect on tumor growth, invasion, and lung metastasis, and it significantly improved the overall survival of mice bearing FGFR-dependent HCC. Infigratinib/Bevacizumab promoted apoptosis, inhibited cell proliferation concomitant with upregulation of p27, and reduction in the expression of FGFR2-4, p-FRS-2, p-ERK1/2, p-p70S6K/4EBP1, Cdc25C, survivin, p-Cdc2, and p-Rb. Combining Infigratinib/Bevacizumab may provide therapeutic benefits for a subpopulation of HCC patients with FGFR-dependent tumors. A high level of FGFR-2/3 may serve as a potential biomarker for patient selection to Infigratinib/Bevacizumab.

New Insight into Therapies Targeting Angiogenesis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a malignancy characterized by neoangiogenesis that is determined by an augmented production of proangiogenesis factors by tumor and adjacent cells. This unbalanced angiogenesis process is a key feature of HCC carcinogenesis and progression. Proangiogenic factors also have a relevant role in the generation and maintenance of an immunosuppressive tumor microenvironment. Several therapeutic options for HCC treatment are based on the inhibition of angiogenesis, both in the early/intermediate stages of the disease and in the late stages of the disease. Conventional treatment options employing antiangiogenic approaches provide for the starving of tumors of their blood supply to avoid the refueling of oxygen and nutrients. An emerging alternative point of view is the normalization of vasculature leading to enhance tumor perfusion and oxygenation, potentially capable, when proposed in combination with other treatments, to improve delivery and efficacy of other therapies, including immunotherapy with checkpoint inhibitors. The introduction of novel biomarkers can be useful for the definition of the most appropriate dose and scheduling for these combination treatment approaches. The present review provides a wide description of the pharmaceutical compounds with an antiangiogenic effect proposed for HCC treatment and investigated in clinical trials, including antibodies and small-molecule kinase inhibitors.

Phosphorylation of mTOR Ser2481 is a key target limiting the efficacy of rapalogs for treating hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Although recent studies facilitate the identification of crucial genes and relevant regulatory pathways, therapeutic approaches against advanced HCC are insufficiently effective. Therefore, we aimed here to develop potent therapeutics to provide a reliable biomarker for the therapeutic efficacy in patients with HCC. To this end, we first compared the cytotoxic effects of various anti-cancer drugs between well differentiated (HAK-1A) and poorly differentiated (HAK-1B) cell lines established from a single HCC tumor. Of various drug screened, HAK-1B cells were more sensitive by a factor of 2,000 to the mTORC1 inhibitors (rapalogs), rapamycin and everolimus, than HAK-1A cells. Although rapalogs inhibited phosphorylation of mTOR Ser2448 in HAK-1A and HAK-1B cells, phosphorylation of mTOR Ser2481 was specifically inhibited only in HAK-1B cells. Silencing of Raptor induced apoptosis and inhibited the growth of only HAK-1B cells. Further, three other cell lines established independently from the tumors of three patients with HCC were also approximately 2,000-fold times more sensitive to rapamycin, which correlated closely with the inhibition of mTOR Ser2481 phosphorylation by rapamycin. Treatment with everolimus markedly inhibited the growth of tumors induced by poorly differentiated HAK-1B and KYN-2 cells and phosphorylation of mTOR Ser2481 in vivo. To our knowledge, this is the first study showing that the phosphorylation of mTOR Ser2481 is selectively inhibited by rapalogs in mTORC1-addicted HCC cells and may be a potential reliable biomarker for the therapeutic efficacy of rapalogs for treating HCC patients.

Locoregional and systemic therapy for hepatocellular carcinoma

The management of hepatocellular carcinoma (HCC) remains challenging due to late presentation and the presence of accompanying liver dysfunction. As such, most patients are not eligible for curative resection and liver transplant. Management in this scenario depends on a number of factors including hepatic function, tumor burden, patency of hepatic vasculature and patients' functional status. Based on these, patients can be offered catheter based intra-arterial therapy for intermediate stage disease and in more advanced disease, sorafenib. Given recent data, regorafenib is now an option following failure of sorafenib. Catheter directed intra-arterial therapy takes advantage of tumor hypervascularity and the unique dual blood supply of the liver, as hepatic tumors receive arterial perfusion via the hepatic artery while the rest of the liver is supplied by the portal vein. This allows selective embolization and delivery of chemotherapeutic agents to the tumor. Compared to best supportive care, intra-arterial therapy offers a survival benefit in intermediate stage HCC and is the recommended approach for treatment. None of the catheter based approaches; including bland embolization, conventional trans-arterial chemoembolization (cTACE), drug eluting bead trans-arterial chemoembolization (DEB-TACE) or trans-arterial radioembolization (TARE) offers a clear advantage over the other, although DEB-TACE may be characterized by less systemic toxicity. All of these approaches are contraindicated in patients with portal vein thrombosis (PVT). On the other hand, intra-arterial, radio embolization, with Yttrium-90 (Y90) can be offered to patients with PVT. The place of this modality in management of HCC is still being investigated. The role of sorafenib in advanced HCC is not in doubt, as until recently, it was the only systemic therapy approved for the management in this setting. This is despite multiple trials evaluating other agents. The addition of sorafenib to catheter-based therapy in intermediate stage disease has also failed to show any benefit. The modest survival benefit with sorafenib and the failure of other targeted agents suggest that it is important to look beyond inhibition of angiogenesis in advanced HCC. Identification of key drivers and mediators of HCC remains paramount for successful drug development. In line with this, it is refreshing that the excitement that has followed developments in cancer immunotherapy is finding its way to HCC with early trials of anti-PD1 monoclonal antibodies showing sufficient activity that phase III trials are now ongoing for Pembrolizumab and Nivolumab in advanced HCC. Future drug development efforts will focus on defining the feasibility of combining different treatment approaches targeting multiple important modulators of HCC.

Transcriptional Induction of Periostin by a Sulfatase 2-TGFβ1-SMAD Signaling Axis Mediates Tumor Angiogenesis in Hepatocellular Carcinoma

Existing antiangiogenic approaches to treat metastatic hepatocellular carcinoma (HCC) are weakly effectual, prompting further study of tumor angiogenesis in this disease setting. Here, we report a novel role for sulfatase 2 (SULF2) in driving HCC angiogenesis. Sulf2-deficient mice (Sulf2 KO) exhibited resistance to diethylnitrosamine-induced HCC and did not develop metastases like wild-type mice (Sulf2 WT). The smaller and less numerous tumors formed in Sulf2 KO mice exhibited a markedly lower microvascular density. In human HCC cells, SULF2 overexpression increased endothelial proliferation, adhesion, chemotaxis, and tube formation in a paracrine fashion. Mechanistic analyses identified the extracellular matrix protein periostin (POSTN), a ligand of αvβ3/5 integrins, as an effector protein in SULF2-induced angiogenesis. POSTN silencing in HCC cells attenuated SULF2-induced angiogenesis and tumor growth in vivo The TGFβ1/SMAD pathway was identified as a critical signaling axis between SULF2 and upregulation of POSTN transcription. In clinical HCC specimens, elevated levels of SULF2 correlated with increased microvascular density, POSTN levels, and relatively poorer patient survival. Together, our findings define an important axis controlling angiogenesis in HCC and a mechanistic foundation for rational drug development. Cancer Res; 77(3); 632-45. ©2016 AACR.

Tissue- and Serum-Associated Biomarkers of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), one of the leading causes of cancer deaths in the world, is offering a challenge to human beings, with the current modes of treatment being a palliative approach. Lack of proper curative or preventive treatment methods encouraged extensive research around the world with an aim to detect a vaccine or therapeutic target biomolecule that could lead to development of a drug or vaccine against HCC. Biomarkers or biological disease markers have emerged as a potential tool as drug/vaccine targets, as they can accurately diagnose, predict, and even prevent the diseases. Biomarker expression in tissue, serum, plasma, or urine can detect tumor in very early stages of its development and monitor the cancer progression and also the effect of therapeutic interventions. Biomarker discoveries are driven by advanced techniques, such as proteomics, transcriptomics, whole genome sequencing, micro- and micro-RNA arrays, and translational clinics. In this review, an overview of the potential of tissue- and serum-associated HCC biomarkers as diagnostic, prognostic, and therapeutic targets for drug development is presented. In addition, we highlight recently developed micro-RNA, long noncoding RNA biomarkers, and single-nucleotide changes, which may be used independently or as complementary biomarkers. These active investigations going on around the world aimed at conquering HCC might show a bright light in the near future.

125I-labeled anti-bFGF monoclonal antibody inhibits growth of hepatocellular carcinoma

AIM: To investigate the inhibitory efficacy of ¹²⁵I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC).

METHODS: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with ¹²⁵I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of ¹²⁵I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), ¹²⁵I-bFGF mAb, ¹²⁵I plus bFGF mAb, bFGF mAb, or ¹²⁵I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction.

RESULTS: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20 °C. After coupling, ¹²⁵I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4 °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, ¹²⁵I, bFGF mAb, ¹²⁵I plus bFGF mAb, and ¹²⁵I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the ¹²⁵I, bFGF mAb, ¹²⁵I plus bFGF mAb, and ¹²⁵I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the ¹²⁵I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the ¹²⁵I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for ¹²⁵I group) compared with the control group.

CONCLUSION: ¹²⁵I-bFGF mAb inhibits growth of HCC xenografts. The coupling effect of ¹²⁵I-bFGF mAb is more effective than the concomitant use of ¹²⁵I and bFGF mAb.

Inhibition of protein kinase C by isojacareubin suppresses hepatocellular carcinoma metastasis and induces apoptosis in vitro and in vivo

Targeted inhibition of protein kinase C (PKC) inhibits hepatocellular carcinoma (HCC) proliferation and metastasis. We previously reported the cytotoxicity of a series of synthetic phenyl-substituted polyoxygenated xanthone derivatives against human HCC. In the current study, the most potent natural product, isojacareubin (ISJ), was synthesized, and its cellular-level antihepatoma activities were evaluated. ISJ significantly inhibited cell proliferation and was highly selective for HCC cells in comparison to nonmalignant QSG-7701 hepatocytes. Moreover, ISJ exhibited pro-apoptotic effects on HepG2 hepatoma cells, as well as impaired HepG2 cell migration and invasion. Furthermore, ISJ was a potent inhibitor of PKC, with differential actions against various PKC isotypes. ISJ selectively inhibited the expression of aPKC (PKCζ) in the cytosol and the translocation of cytosolic PKCζ to membrane site. ISJ also directly interacted with cPKC (PKCα) and nPKC (PKCδ, PKCε and PKCμ) and thereby inhibited the early response of major MAPK phosphorylation and the late response of HCC cell invasion and proliferation. In a hepatoma xenograft model, ISJ pretreatment resulted in significant antihepatoma activity in vivo. These findings identify ISJ as a promising lead compound for the development of new antihepatoma agents and may guide the search for additional selective PKC inhibitors.

Signaling pathway/molecular targets and new targeted agents under development in hepatocellular carcinoma

Advances in molecular cell biology over the last decade have clarified the mechanisms involved in cancer growth, invasion, and metastasis, and enabled the development of molecular-targeted agents. To date, sorafenib is the only molecular-targeted agent whose survival benefit has been demonstrated in two global phase III randomized controlled trials, and has been approved worldwide. Phase III clinical trials of other molecular targeted agents comparing them with sorafenib as first-line treatment agents are ongoing. Those agents target the vascular endothelial growth factor, platelet-derived growth factor receptors, as well as target the epidermal growth factor receptor, insulin-like growth factor receptor and mammalian target of rapamycin, in addition to other molecules targeting other components of the signal transduction pathways. In addition, the combination of sorafenib with standard treatment, such as resection, ablation, transarterial embolization, and hepatic arterial infusion chemotherapy are ongoing. This review outlines the main pathways involved in the development and progression of hepatocellular carcinoma and the new agents that target these pathways. Finally, the current statuses of clinical trials of new agents or combination therapy with sorafenib and standard treatment will also be discussed.

A novel monoclonal antibody to fibroblast growth factor 2 effectively inhibits growth of hepatocellular carcinoma xenografts

Expression of fibroblast growth factor 2 (FGF2) is believed to be a contributing factor to the growth of a number of tumor types, including hepatocellular carcinoma (HCC). However, the potential of monoclonal antibodies that neutralize FGF2 for treatment of patients with cancer has not yet been explored in clinical trials. We therefore generated a novel monoclonal antibody (mAb), GAL-F2, specific for FGF2 and characterized its properties in vitro and in vivo. GAL-F2 binds to a different epitope than several previous anti-FGF2 mAbs tested. This novel epitope was defined using chimeric FGF1/FGF2 proteins and alanine scanning mutagenesis and was shown to comprise amino acids in both the amino and carboxy regions of FGF2. GAL-F2 blocked binding of FGF2 to each of its four cellular receptors, strongly inhibited FGF2-induced proliferation and downstream signaling in human umbilical vein endothelial cells, and inhibited proliferation and downstream signaling in two HCC cell lines. Moreover, GAL-F2, administered at 5 mg/kg i.p. twice weekly, potently inhibited growth of xenografts of the SMMC-7721, HEP-G2, and SK-HEP-1 human HCC cell lines in nude mice, and in some models, had a strong additive effect with an anti-VEGF mAb or sorafenib. Treatment with GAL-F2 also blocked angiogenesis and inhibited downstream cellular signaling in xenografts, indicating its antitumor mechanism of action. Our report supports clinical testing of a humanized form of the GAL-F2 mAb for treatment of HCC and potentially other cancers.

Evolving therapies in the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The major etiologies and risk factors for HCC development are well defined and some of the steps involved in hepatocarcinogenesis have been elucidated in recent years. Therapeutic options that can be applied in curative or palliative intention are available and are dependent on the HCC stage. The therapeutic options fall into five main categories: (1) surgical interventions, including tumor resection and liver transplantation, (2) percutaneous interventions, including ethanol injection and radiofrequency thermal ablation, (3) transarterial interventions, including embolization and chemoembolization, (4) radiation therapy, and (5) drugs as well as gene and immune therapies. Until recently, no therapy existed for patients with advanced HCC. In 2007 a multikinase inhibitor (sorafenib) showed for the first time a significant increase in overall survival in patients with advanced HCC. Furthermore, several other agents that target different factors of hepatocarcinogenesis (eg, epidermal growth factor, insulin-like growth factors, hepatocyte growth factor, vascular endothelial growth factor, fibroblast growth factor, platelet-derived growth factor, and the transforming growth factors-α and -β), have emerged and been tested in clinical trials. This review gives an overview of the current therapeutic strategies and their clinical impact.

The tumor microenvironment in hepatocellular carcinoma: current status and therapeutic targets

A growing body of literature highlights the cross-talk between tumor cells and the surrounding peri-tumoral stroma as a key modulator of the processes of hepatocarcinogenesis, epithelial mesenchymal transition (EMT), tumor invasion and metastasis. The tumor microenvironment can be broadly classified into cellular and non-cellular components. The major cellular components include hepatic stellate cells, fibroblasts, immune, and endothelial cells. These cell types produce the non-cellular components of the tumor stroma, including extracellular matrix (ECM) proteins, proteolytic enzymes, growth factors and inflammatory cytokines. The non-cellular component of the tumor stroma modulates hepatocellular carcinoma (HCC) biology by effects on cancer signaling pathways in tumor cells and on tumor invasion and metastasis. Global gene expression profiling of HCC has revealed that the tumor microenvironment is an important component in the biologic and prognostic classification of HCC. There are substantial efforts underway to develop novel drugs targeting tumor-stromal interactions. In this review, we discuss the current knowledge about the role of the tumor microenvironment in pathogenesis of HCC, the role of the tumor microenvironment in the classification of HCC and efforts to develop treatments targeting the tumor microenvironment.

Current status of molecularly targeted therapy for hepatocellular carcinoma: clinical practice

In recent years, molecular-targeted agents have been used clinically to treat various malignant tumors. In May 2009, sorafenib (Nexavar) was approved in Japan for "unresectable hepatocellular carcinoma (HCC)", and was the first molecular-targeted agent for use in liver cancer. To date, sorafenib is the only molecular-targeted agent whose survival benefit has been demonstrated in two global phase III randomized controlled trials, and it has now been approved worldwide. Phase III clinical trials are now underway to compare other molecular-targeted agents with sorafenib as first-line treatment agents, and to evaluate other multi-kinase inhibitors of the vascular endothelial growth factor and platelet-derived growth factor receptors, as well as drugs targeting the epidermal growth factor receptor, insulin-like growth factor receptor, and mammalian target of rapamycin, in addition to other molecules targeting other components of the signal transduction pathways. This review outlines the main pathways involved in the development and progression of HCC and the agents that target these pathways.

Heparanase and hepatocellular carcinoma: Promoter or inhibitor?

Heparan sulphate proteoglycans (HSPGs) consist of a core protein and several heparan sulphate (HS) side chains covalently linked. HS also binds a great deal of growth factors, chemokines, cytokines and enzymes to the extracellular matrix and cell surface. Heparanase can specially cleave HS side chains from HSPGs. There are a lot of conflicting reports about the role of heparanase in hepatocellular carcinoma (HCC). Heparanase is involved in hepatitis B virus infection and hepatitis C virus infection, the activation of signal pathways, metastasis and apoptosis of HCC. Heparanase is synthesized as an inactive precursor within late endosomes and lysosomes. Then heparanase undergoes proteolytic cleavage to form an active enzyme in lysosomes. Active heparanase translocates to the nucleus, cell surface or extracellular matrix. Different locations of heparanase may exert different activities on tumor progression. Furthermore, enzymatic activities and non-enzymatic activities of heparanase may play different roles during HCC development. The expression level of heparanase may also contribute to the discrepant effects of heparanase. Growth promoting as well as growth inhibiting sequences are contained within the tumor cell surface heparan sulfate. Degrading different HSPGs by heparanase may play different roles in HCC. Systemic studies examining the processing, expression, localization and function of heparanase should shed a light on the role of heparanase in HCC.

Resident hepatocyte fibroblast growth factor receptor 4 limits hepatocarcinogenesis

Fibroblast growth factor (FGF) family signaling mediates cell-to-cell communication in development and organ homeostasis in adults. Of the FGF receptor (FGFR) isotypes, FGFR4 is the sole resident isotype present in mature parenchymal hepatocytes. FGFR1 that is normally associated with activated nonparenchymal cells appears ectopically in hepatoma cells. Ectopic expression and chronic activity of FGFR1 in hepatocytes accelerates diethylnitrosamine (DEN)-initiated hepatocarcinogenesis by driving unrestrained cell proliferation and tumor angiogenesis. Hepatocyte FGFR4 mediates liver's role in systemic cholesterol/bile acid and lipid metabolism and affects proper hepatolobular restoration after damage without effect on cell proliferation. Here we ask whether FGFR4 plays a role in progression of hepatocellular carcinoma (HCC). We report that although spontaneous HCC was not detected in livers of FGFR4-deficient mice, the ablation of FGFR4 accelerated DEN-induced hepatocarcinogenesis. In contrast to FGFR1 that induced a strong mitogenic response and depressed rate of cell death in hepatoma cells, FGFR4 failed to induce a mitogenic response and increased the rate of cell death. FGFR1 but not FGFR4 induced cyclin D1 and repressed p27 expression. Analysis of activation of Erk, JNK, and PI3K-related AKT signaling pathways indicated that in contrast to FGFR1, FGFR4 failed to sustain Erk activation and did not activate AKT. These differences may underlie the opposing effects of FGFR1 and FGFR4. These results suggest that in contrast to ectopic FGFR1 that is a strong promoter of hepatoma, resident FGFR4 that mediates differentiated hepatocyte metabolic functions also serves to suppress hepatoma progression.

Overexpression of Dickkopf 3 in hepatoblastomas and hepatocellular carcinomas

Dickkopf 3 (Dkk3) is a protein expressed at a very early stage of hepatogenesis. In this study, we examined whether Dkk3 was related to a premature or dedifferentiated nature in hepatoblastomas (HBLs) and hepatocellular carcinomas (HCCs). It was demonstrated that Dkk3 was overexpressed in HBLs and HCCs and that its expression was more frequent in the former than in the latter, being consistent with the fact that most HBLs show an embryonal or fetal hepatic histology, whereas there was no distinct relationship between Dkk3 expression and clinical data or histology. All of the HBLs expressed Dkk3, alpha-fetoprotein (AFP), or both proteins, suggesting that, similar to AFP, Dkk3 is another potentially useful biomarker detecting a wide range of HBLs. Furthermore, Dkk3 and AFP were expressed reciprocally in the tumors. These results suggest that Dkk3 may be related to the premature or dedifferentiated nature of HBLs and HCCs, whereas AFP may be related to a more differentiated nature. Thus, assessment of Dkk3 and AFP may be useful in the diagnosis of hepatic tumors.

MicroRNAs: target recognition and regulatory functions

MicroRNAs (miRNAs) are endogenous approximately 23 nt RNAs that play important gene-regulatory roles in animals and plants by pairing to the mRNAs of protein-coding genes to direct their posttranscriptional repression. This review outlines the current understanding of miRNA target recognition in animals and discusses the widespread impact of miRNAs on both the expression and evolution of protein-coding genes.

Genetic profile of Egyptian hepatocellular-carcinoma associated with hepatitis C virus Genotype 4 by 15 K cDNA microarray: preliminary study

Background

Hepatocellular carcinoma (HCC) is a preventable disease rather than a curable one, since there is no well-documented effective treatment modality until now, making the molecular study of this disease mandatory.

Findings

We studied gene expression profile of 17 Egyptian HCC patients associated with HCV genotype-4 infection by c-DNA microarray. Out of the 15,660 studied genes, 446 were differentially expressed; 180 of them were up regulated and 134 were down regulated. Seventeen genes out of the 180 up-regulated genes are involved in 28 different pathways. Protein phosphatase 3 (PPP3R1) is involved in 10 different pathways followed by fibroblast growth factor receptor 1 (FGFR1), Cas-Br-M ecotropic retroviral transforming sequence b (CBLB), spleen tyrosine kinase (SYK) involved in three pathways; bone morphogenetic protein 8a (BMP8A), laminin alpha 3 (LAMA3), cell division cycle 23 (CDC23) involved in 2 pathways and NOTCH4 which regulate Notch signaling pathway. On the other hand, 25 out of the 134 down-regulated genes are involved in 20 different pathways. Integrin alpha V alpha polypeptide antigen CD51 (ITGVA) is involved in 4 pathways followed by lymphotoxin alpha (TNF superfamily, member 1) (LTA) involved in 3 pathways and alpha-2-macroglobulin (A2M), phosphorylase kinase alpha 2-liver (PHKA2) and MAGI1 membrane associated guanylate kinase 1 (MAGI1) involved in 2 pathways. In addition, 22 genes showed significantly differential expression between HCC cases with cirrhosis and without cirrhosis. Confirmation analysis was performed on subsets of these genes by RT-PCR, including some up-regulated genes such as CDK4, Bax, NOTCH4 and some down-regulated genes such as ISGF3G, TNF, and VISA.

Conclusion

This is the first preliminary study on gene expression profile in Egyptian HCC patients associated with HCV-Genotype-4 using the cDNA microarray. The identified genes could provide a new gate for prognostic and diagnostic markers for HCC associated with HCV. They could also be used to identify candidate genes for molecular target therapy.

Growth factor receptors and related signalling pathways as targets for novel treatment strategies of hepatocellular cancer

Growth factors and their corresponding receptors are commonly overexpressed and/or dysregulated in many cancers including hepatocellular cancer (HCC). Clinical trials indicate that growth factor receptors and their related signalling pathways play important roles in HCC cancer etiology and progression, thus providing rational targets for innovative cancer therapies. A number of strategies including monoclonal antibodies, tyrosine kinase inhibitors (“small molecule inhibitors”) and antisense oligonucleotides have already been evaluated for their potency to inhibit the activity and downstream signalling cascades of these receptors in HCC. First clinical trials have also shown that multi-kinase inhibition is an effective novel treatment strategy in HCC. In this respect sorafenib, an inhibitor of Raf-, VEGF- and PDGF-signalling, is the first multi-kinase inhibitor that has been approved by the FDA for the treatment of advanced HCC. Moreover, the serine-threonine kinase of mammalian target of rapamycin (mTOR) upon which the signalling of several growth factor receptors converge plays a central role in cancer cell proliferation. mTOR inhibition of HCC is currently also being studied in preclinical trials. As HCCs represent hypervascularized neoplasms, inhibition of tumour vessel formation via interfering with the VEGF/VEGFR system is another promising approach in HCC treatment. This review will summarize the current status of the various growth factor receptor-based treatment strategies and in view of the multitude of novel targeted approaches, the rationale for combination therapies for advanced HCC treatment will also be taken into account.

Current status and perspective of antiangiogenic therapy for cancer: hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is well known as a typical angiogenic tumor, especially in the moderately to poorly differentiated type. Such clinicopathological characteristics are not only useful for imaging diagnosis but are also applicable to the treatment of HCC. In addition, recent molecular studies have revealed that angiogenesis is closely related to hepatocarcinogenesis. In this review, the molecular mechanism of HCC angiogenesis and the antiangiogenic prevention of HCC are reviewed to introduce the latest trends in antiangiogenic treatment of cancers, including HCC.

Angiogenesis in hepatocellular carcinoma: the retrospectives and perspectives

Hepatocellular carcinoma (HCC) is a typical hypervascular tumor. Many angiogenic factors have been studied in HCC, and several anti-angiogenic therapies have been tested in animal models and patients. This paper summarizes the latest findings, especially regarding the clinical significance of endothelial cell markers and angiogenic factors in HCC, and experimental and clinical anti-angiogenesis therapies. Further developments in this area, such as endothelial cell-oriented research and better experimental and clinical designs in the evaluation of anti-angiogenic therapies are discussed.