Fibroblast growth factor 19 expression correlates with tumor progression and poorer prognosis of hepatocellular carcinoma

Novel combination of sorafenib and celecoxib provides synergistic anti-proliferative and pro-apoptotic effects in human liver cancer cells

Molecular targeted therapy has shown promise as a treatment for advanced hepatocellular carcinoma (HCC). Sorafenib, a multikinase inhibitor, recently received FDA approval for the treatment of advanced HCC. However, although sorafenib is well tolerated, concern for its safety has been expressed. Celecoxib (Celebrex®) is a selective cyclooxygenase-2 (COX-2) inhibitor which exhibits antitumor effects in human HCC cells. The present study examined the interaction between celecoxib and sorafenib in two human liver tumor cell lines HepG2 and Huh7. Our data showed that each inhibitor alone reduced cell growth and the combination of celecoxib with sorafenib synergistically inhibited cell growth and increased apoptosis. To better understand the molecular mechanisms underlying the synergistic antitumor activity of the combination, we investigated the expression profile of the combination-treated liver cancer cell lines using microarray analysis. Combination treatment significantly altered expression levels of 1,986 and 2,483 transcripts in HepG2 and Huh7 cells, respectively. Genes functionally involved in cell death, signal transduction and regulation of transcription were predominantly up-regulated, while genes implicated in metabolism, cell-cycle control and DNA replication and repair were mainly down-regulated upon treatment. However, combination-treated HCC cell lines displayed specificity in the expression and activity of crucial factors involved in hepatocarcinogenesis. The altered expression of some of these genes was confirmed by semi-quantitative and quantitative RT-PCR and by Western blotting. Many novel genes emerged from our transcriptomic analyses, and further functional analyses may determine whether these genes can serve as potential molecular targets for more effective anti-HCC strategies.

Thrombocytosis and hepatocellular carcinoma

BACKGROUND

Thrombocytopenia has been reported to be both a risk factor for hepatocellular carcinoma (HCC) development as well as a prognostic factor. Many HCCs also occur in presence of normal platelets.

AIM

To examine a cohort of HCC patients with associated thrombocytosis.

METHODS

Records were examined of a cohort of 634 biopsy-proven and randomly presenting HCC patients without thrombocytopenia.

RESULTS

In the total cohort, 52 patients were identified with thrombocytosis (platelet levels >400 × 10(9)/L) and compared with 582 patients with normal platelet values. The average tumor sizes were 13.1 versus 8.8 cm (p < 0.0001), and their total average bilirubin levels were 0.9 versus 1.5 (p = 0.02), comparing thrombocytosis patients versus normal platelet count HCC patients. These differences were even more pronounced in patients with HCC sizes >5 cm. Thrombocytosis patients were younger and had less cirrhosis, but similar percent with hepatitis B or C or alcohol consumption.

CONCLUSION

Thrombocytosis in association with HCC occurs in patients with larger tumor sizes and better liver function.

A call to ARMS: targeting the PAX3-FOXO1 gene in alveolar rhabdomyosarcoma

INTRODUCTION

Expression of fusion oncoproteins generated by recurrent chromosomal translocations represents a major tumorigenic mechanism characteristic of multiple cancers, including one-third of all sarcomas. Oncogenic fusion genes provide novel targets for therapeutic intervention. The PAX3-FOXO1 oncoprotein in alveolar rhabdomyosarcoma (ARMS) is presented as a paradigm to examine therapeutic strategies for targeting sarcoma-associated fusion genes.

AREAS COVERED

This review discusses the role of PAX3-FOXO1 in ARMS tumors. Besides evaluating various approaches to molecularly target PAX3-FOXO1 itself, this review highlights therapeutically attractive downstream genes activated by PAX3-FOXO1.

EXPERT OPINION

Oncogenic fusion proteins represent desirable therapeutic targets because their expression is specific to tumor cells, but these fusions generally characterize rare malignancies. Full development and testing of potential drugs targeted to these fusions are complicated by the small numbers of patients in these disease categories. Although efforts to develop targeted therapies against fusion proteins should continue, molecular targets that are applicable to a broader tumor landscape should be pursued. A shift of the traditional paradigm to view therapeutic intervention as target-specific rather than tumor-specific will help to circumvent the challenges posed by rare tumors and maximize the possibility of developing successful new treatments for patients with these rare translocation-associated sarcomas.

FGFR4 and TGF-β1 expression in hepatocellular carcinoma: correlation with clinicopathological features and prognosis

OBJECTIVE

To investigate the expression and correlation of transforming growth factor-β1 (TGF-β1) and fibroblast growth factor receptor 4 (FGFR4) in human hepatocellular carcinoma (HCC) and the relationship with clinicopathological features and prognosis.

MATERIALS AND METHODS

The expression of TGF-β1 and FGFR4 in 126 HCC samples was detected immunohistochemically. Combined with clinical postoperative follow-up data, the expression of TGF-β1 and FGFR4 in HCC and the relationship with the prognosis of patients were analyzed by statistically.

RESULTS

The positive expression rate of TGF-β1 was 84.1% (106/126) in tumors, and that in peritumoral liver tissues was 64.3% (81/126); the positive expression rate of FGFR4 in tumors was 74.6% (94/126) and that in peritumoral liver tissues was 57.1% (72/126). The expression of TGF-β1 and FGFR4 in the carcinoma tissues was significantly higher than that in peritumoral liver tissues (p < 0.05). Intratumoral TGF-β1 and FGFR4 expression was associated with TNM stage (p < 0.05). TGF-β1 and FGFR4 expression levels didn't significantly correlate with other clinicopathological parameters, including age, sex, tumor size, serum AFP level, tumor differentiation, lymph node metastasis, etc. (p > 0.05). TGF-β1 expression was positively correlated with FGFR4 expression (r = 0.595, p < 0.05). Patients with positive FGFR4 or TGF-β1 expression had shorter overall survival compared with negative expression (p < 0.05).

CONCLUSIONS

The expression of TGF-β1 and FGFR4 could make synergy on the occurrence and progression of HCC, and may be used as prognosis indicators for HCC patients.

Regulation of amphiregulin gene expression by β-catenin signaling in human hepatocellular carcinoma cells: a novel crosstalk between FGF19 and the EGFR system

Hepatocellular carcinoma (HCC) is the most prevalent liver tumor and a deadly disease with limited therapeutic options. Dysregulation of cell signaling pathways is a common denominator in tumorigenesis, including hepatocarcinogenesis. The epidermal growth factor receptor (EGFR) signaling system is commonly activated in HCC, and is currently being evaluated as a therapeutic target in combination therapies. We and others have identified a central role for the EGFR ligand amphiregulin (AR) in the proliferation, survival and drug resistance of HCC cells. AR expression is frequently up-regulated in HCC tissues and cells through mechanisms not completely known. Here we identify the β-catenin signaling pathway as a novel mechanism leading to transcriptional activation of the AR gene in human HCC cells. Activation of β-catenin signaling, or expression of the T41A β-catenin active mutant, led to the induction of AR expression involving three specific β-catenin-Tcf responsive elements in its proximal promoter. We demonstrate that HCC cells expressing the T41A β-catenin active mutant show enhanced proliferation that is dependent in part on AR expression and EGFR signaling. We also demonstrate here a novel cross-talk of the EGFR system with fibroblast growth factor 19 (FGF19). FGF19 is a recently identified driver gene in hepatocarcinogenesis and an activator of β-catenin signaling in HCC and colon cancer cells. We show that FGF19 induced AR gene expression through the β-catenin pathway in human HCC cells. Importantly, AR up-regulation and EGFR signaling participated in the induction of cyclin D1 and cell proliferation elicited by FGF19. Finally, we demonstrate a positive correlation between FGF19 and AR expression in human HCC tissues, therefore supporting in clinical samples our experimental observations. These findings identify the AR/EGFR system as a key mediator of FGF19 responses in HCC cells involving β-catenin signaling, and suggest that combined targeting of FGF19 and AR/EGFR may enhance therapeutic efficacy.

Emerging role of fibroblast growth factors 15/19 and 21 as metabolic integrators in the liver

Fibroblast growth factors (FGFs) 15/19 and 21 belong to the FGF endocrine subfamily. They present the intriguing characteristic to be transcribed and secreted in certain tissues and to act as hormones. The insulin-mimetic properties of FGF21 and the regulatory role of FGF15/19 in bile acid and glucose homeostasis endorse these hormones as druggable targets in metabolic disorders. Here, we present details on discoveries, identification, transcriptional regulation, and mechanism of actions of FGF15/19 and FGF21 with a critical perspective view on their putative role as metabolic integrators in the liver.

Prevention of hepatocellular carcinoma: potential targets, experimental models, and clinical challenges

Chronic fibrotic liver diseases such as viral hepatitis eventually develop liver cirrhosis, which causes occurrence of hepatocellular carcinoma (HCC). Given the limited therapeutic efficacy in advanced HCC, prevention of HCC development could be an effective strategy for improving patient prognosis. However, there is still no established therapy to meet the goal. Studies have elucidated a wide variety of molecular mechanisms and signaling pathways involved in HCC development. Genetically-engineered or chemically-treated experimental models of cirrhosis and HCC have been developed and shown their potential value in investigating molecular therapeutic targets and diagnostic biomarkers for HCC prevention. In this review, we overview potential targets of prevention and currently available experimental models, and discuss strategies to translate the findings into clinical practice.

Identification and extensive analysis of inverted-duplicated HBV integration in a human hepatocellular carcinoma cell line

Hepatitis B virus (HBV) DNA is often integrated into hepatocellular carcinoma (HCC). Although the relationship between HBV integration and HCC development has been widely studied, the role of HBV integration in HCC development is still not completely understood. In the present study, we constructed a pooled BAC library of 9 established cell lines derived from HCC patients with HBV infections. By amplifying viral genes and superpooling of BAC clones, we identified 2 clones harboring integrated HBV DNA. Screening of host-virus junctions by repeated sequencing revealed an HBV DNA integration site on chromosome 11q13 in the SNU-886 cell line. The structure and rearrangement of integrated HBV DNA were extensively analyzed. An inverted duplicated structure, with fusion of at least 2 HBV DNA molecules in opposite orientations, was identified in the region. The gene expression of cancer-related genes increased near the viral integration site in HCC cell line SNU-886.