Etiologic influence on chromosomal aberrations in European hepatocellular carcinoma identified by CGH. Pathol Res Pract. 2013;209:380-387. [PMID: 23706943 DOI: 10.1016/j.prp.2013.04.004]

An integrative view on glucagon function and putative role in the progression of pancreatic neuroendocrine tumours (pNETs) and hepatocellular carcinomas (HCC)

Cancer metabolism research area evolved greatly, however, is still unknown the impact of systemic metabolism control and diet on cancer. It makes sense that systemic regulators of metabolism can act directly on cancer cells and activate signalling, prompting metabolic remodelling needed to sustain cancer cell survival, tumour growth and disease progression. In the present review, we describe the main glucagon functions in the control of glycaemia and of metabolic pathways overall. Furthermore, an integrative view on how glucagon and related signalling pathways can contribute for pancreatic neuroendocrine tumours (pNETs) and hepatocellular carcinomas (HCC) progression, since pancreas and liver are the major organs exposed to higher levels of glucagon, pancreas as a producer and liver as a scavenger. The main objective is to bring to discussion some glucagon-dependent mechanisms by presenting an integrative view on microenvironmental and systemic aspects in pNETs and HCC biology.

Circular RNA hsa_Circ_101141 as a Competing Endogenous RNA Facilitates Tumorigenesis of Hepatocellular Carcinoma by Regulating miR-1297/ROCK1 Pathway

As a novel class of noncoding RNAs, circular RNAs (circRNAs) have been recently reported to be involved in cell development and function. However, the functional role of circRNAs in hepatocellular carcinoma (HCC) remains unclear. In the present study, we found that the expression of human circ_101141 was upregulated in HCC tissues and cells. In addition, downregulation of circ_101141 dramatically inhibited cell proliferation, migration, and invasion in HCC cells. In addition, by using the bioinformatics tools, the potential target of circ_101141 was predicted. Mechanistic investigations indicated that circ_101141 acted as a miR-1297 “sponge”; meanwhile, Rho-associated, coiled-coil-containing protein kinase 1 (ROCK1) was a direct target of miR-1297. Further experiments demonstrated that circ_101141 contributed to the progression of HCC by acting as competing endogenous RNA (ceRNA) of miR-1297 to regulate ROCK1 expression. Furthermore, knockdown of circ_101141 attenuated HCC tumorigenesis in vivo. Taken together, these findings indicated that circRNA circ_101141 acted as a ceRNA to facilitate tumorigenesis of HCC by regulating miR-1297/ROCK1 pathway.

Recent advances in the molecular mechanism of sex disparity in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is more frequently observed and aggressive in men compared with women. Increasing evidence demonstrates that the sex disparity appears to be mediated by the stimulatory effects of androgens and the protective effects of estrogen in the development and progression of HCC. In the past few decades, studies on the sex difference of HCC mainly focused on the effect of sex hormones on the transactivation of hepatitis B virus X protein and the release of inflammatory cytokines, and these studies have further intensified in recent years. Sex hormones are also involved in genetic alterations and DNA damage repair in hepatocytes through binding to their specific cellular receptors and affecting the corresponding signaling pathways. Furthermore, the theory of sex chromosomes participating in HCC has been considered. The present review discussed the recent advances in the molecular mechanisms of sex disparity in HCC, with the aim of improving the understanding of the underlying critical factors and exploring more effective methods for the prevention and treatment of HCC.

Hepatitis B virus PreS2-mutant large surface antigen activates store-operated calcium entry and promotes chromosome instability

Hepatitis B virus (HBV) is a driver of hepatocellular carcinoma, and two viral products, X and large surface antigen (LHBS), are viral oncoproteins. During chronic viral infection, immune-escape mutants on the preS2 region of LHBS (preS2-LHBS) are gain-of-function mutations that are linked to preneoplastic ground glass hepatocytes (GGHs) and early disease onset of hepatocellular carcinoma. Here, we show that preS2-LHBS provoked calcium release from the endoplasmic reticulum (ER) and triggered stored-operated calcium entry (SOCE). The activation of SOCE increased ER and plasma membrane (PM) connections, which was linked by ER- resident stromal interaction molecule-1 (STIM1) protein and PM-resident calcium release- activated calcium modulator 1 (Orai1). Persistent activation of SOCE induced centrosome overduplication, aberrant multipolar division, chromosome aneuploidy, anchorage-independent growth, and xenograft tumorigenesis in hepatocytes expressing preS2- LHBS. Chemical inhibitions of SOCE machinery and silencing of STIM1 significantly reduced centrosome numbers, multipolar division, and xenograft tumorigenesis induced by preS2-LHBS. These results provide the first mechanistic link between calcium homeostasis and chromosome instability in hepatocytes carrying preS2-LHBS. Therefore, persistent activation of SOCE represents a novel pathological mechanism in HBV-mediated hepatocarcinogenesis.

Tumor-derived CD4+CD25+regulatory T cells inhibit dendritic cells function by CTLA-4

PURPOSE

CD4+CD25+regulatoryT cells (Tregs) play an important role in anti-tumor immune responses. Poor prognosis and declining survival rates have intimate connection with high Treg expression in cancer patients. Cytotoxic T Lymphocyte-associated protein (CTLA-4) is one of the most prominent molecules on Treg. In our previous research, we have demonstrated that HCC-derived Tregs can interfere with Dendritic cells (DCs) function and down-modulate CD80/CD86 on DCs in vitro in a cell-contact dependent way. However the mechanism of how HCC-derived Treg affect DC phenotype are not very clear. Therefore, we investigated the function of CTLA-4 in anti-tumor immune responses.

MATERIALS AND METHODS

We established BABL/C mouse with hepatocellular carcinoma model, and tumor-derived Tregs were purified by magnetic cell sorting using mouse CD4+CD25+regulatoryT cell isolation kit. Splenic DCs were enriched using CD11c-conjugated microbeads. Then splenic DCs co-cultured with tumor-derived Tregs and antibody-blocking experiments was performed.

RESULTS

In our research, we found the down-modulation of CD80/CD86 on DCs was inhibited by blocking CTLA-4. HCC-derived Tregs down-modulated CD80/CD86 on DCs in a CTLA-4-dependent way. Blockade of CTLA-4 can lead to increase DC-mediated immunity.

CONCLUSION

CTLA-4 play a vital role in Treg-mediated immnue inhibition and this discovery can open up new ideas for the development of therapeutic strategies.

Genetic alterations in hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Although recent advances in therapeutic approaches for treating HCC have improved the prognoses of patients with HCC, this cancer is still associated with a poor survival rate mainly due to late diagnosis. Therefore, a diagnosis must be made sufficiently early to perform curative and effective treatments. There is a need for a deeper understanding of the molecular mechanisms underlying the initiation and progression of HCC because these mechanisms are critical for making early diagnoses and developing novel therapeutic strategies. Over the past decade, much progress has been made in elucidating the molecular mechanisms underlying hepatocarcinogenesis. In particular, recent advances in next-generation sequencing technologies have revealed numerous genetic alterations, including recurrently mutated genes and dysregulated signaling pathways in HCC. A better understanding of the genetic alterations in HCC could contribute to identifying potential driver mutations and discovering novel therapeutic targets in the future. In this article, we summarize the current advances in research on the genetic alterations, including genomic instability, single-nucleotide polymorphisms, somatic mutations and deregulated signaling pathways, implicated in the initiation and progression of HCC. We also attempt to elucidate some of the genetic mechanisms that contribute to making early diagnoses of and developing molecularly targeted therapies for HCC.

Hepatocellular carcinoma: Surgeon's view on latest findings and future perspectives

Hepatocellular carcinoma (HCC) is the most common liver-derived malignancy with a high fatality rate. Risk factors for the development of HCC have been identified and are clearly described. However, due to the lack of tumor-specific symptoms, HCC are diagnosed at progressed tumor stages in most patients, and thus curative therapeutic options are limited. The focus of this review is on surgical therapeutic options which can be offered to patients with HCC with special regard to recent findings, not exclusively focused on surgical therapy, but also to other treatment modalities. Further, potential promising future perspectives for the treatment of HCC are discussed.

Diagnosis and treatment of hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is one of the most common malignancies leading to high mortality rates in the general population; in cirrhotic patients, it is the primary cause of death. The diagnosis is usually delayed in spite of at-risk population screening recommendations, i.e., patients infected with hepatitis B or C virus. Hepatocarcinogenesis hinges on a great number of genetic and molecular abnormalities that lead to tumor angiogenesis and foster their dissemination potential. The diagnosis is mainly based on imaging studies such as computed tomography and magnetic resonance, in which lesions present a characteristic classical pattern of early arterial enhancement followed by contrast medium “washout” in late venous phase. On occasion, when imaging studies are not conclusive, biopsy of the lesion must be performed to establish the diagnosis. The Barcelona Clinic Liver Cancer staging method is the most frequently used worldwide and recommended by the international guidelines of HCC management. Currently available treatments include tumor resection, liver transplant, sorafenib and loco-regional therapies (alcoholization, radiofrequency ablation, chemoembolization). The prognosis of hepatocarcinoma is determined according to the lesion’s stage and in cirrhotic patients, on residual liver function. Curative treatments, such as liver transplant, are sought in patients diagnosed in early stages; patients in more advanced stages, were not greatly benefitted by chemotherapy in terms of survival until the advent of target molecules such as sorafenib.

Recurrent genetic alterations in hepatitis C-associated hepatocellular carcinoma detected by genomic microarray: a genetic, clinical and pathological correlation study

Background

In the US, approximately 50% of hepatocellular carcinoma (HCC) is caused by hepatitis-C virus (HCV) infection. The molecular mechanism of a malignant transformation of hepatocyte induced by HCV infection is still largely unclear. There are several clinical and pathological staging systems for HCC, but none of them include biological parameters as predictors for prognosis and there has not been a standardized molecular classification of HCC. To understand the underlying pathogenic genetic alterations in HCV-associated HCC and aid in molecular classification of HCC and patient prognosis, microarray analysis of DNA copy number alterations in HCC were conducted using whole genome microarray with DNA from formalin-fixed paraffin-embedded (FFPE) specimens of both cancer tissues and paired nearby cirrhotic non-neoplastic tissues.

Results

Our results show that the most common chromosomal aberrations (>5 Mb) observed in HCC were chromosomal gains of 1q (80%), 8q (60%), 7q (40%), 5p (33%), 7p (33%), Xq (33%), 5q (27%), and Xp (20%), as well as chromosome losses of 17p (40%), 4q21.21-q26 (33%), 8p (33%), 1p36.11-pter (20%), and 9p (20%). Statistically significant smaller copy number alterations (3.9 kb to 644 kb) were identified using STAC algorithm, including losses of FGFR3, RECQL4, NOTCH1, PTEN, TSC2, and/or ASPSCR1 and gains of ETV1and/or MAF. Correlation analysis between genetic data and pathological data showed that gain of 1q21.1-q23.2 and gain of 8q11.1q13.1 are significantly associated with grade 2–4 and moderately or poorly differentiated HCCs, and gain of chromosome 5q was significantly associated with HCCs with vascular invasion, while gain of chromosome 7q is significantly associated with stage I HCCs.

Conclusions

This study has provided a detailed map of genomic aberrations occurring in HCV-associated HCC and has suggested candidate genes. In addition, gene enrichment analysis on the recurrent abnormal regions indicated NF- kappaB and BMP signaling pathways in HCC development and progression. This study demonstrated that genomic microarray test can be used to distinguish HCC from non- neoplastic cirrhotic nodules and to identify prognostic factors associated with HCC progression using pathologically characterized FFPE samples. Our data support the utility of genomic microarray test for the diagnosis, risk stratification, and pathogenic studies of HCC.