Intrahepatic hepatitis B virus large surface antigen induces hepatocyte hyperploidy via failure of cytokinesis

Detection of serum large and middle hepatitis B virus surface proteins: A novel potential diagnostic and prognostic biomarker for chronic hepatitis B

BACKGROUND

The significance of large (LHB) and middle (MHB) HBV surface proteins in chronic hepatitis B (CHB) remains uncertain. This study investigates the role of LHB and MHB in different infection phases and liver diseases.

METHODS

Serum samples from 217 patients with HBV chronic infection, CHB, liver cirrhosis (LC), and hepatocellular carcinoma (HCC) were subjected to quantification of LHB and MHB using ELISA.

RESULTS

Positive correlations were observed among LHB, MHB, and LHB/HBsAg, with HBV serum markers including HBsAg, HBeAg, and HBV DNA. (P < 0.0001). In HBeAg-positive chronic infection, LHB and MHB were higher than in HBeAg-positive CHB (P < 0.01). In HBeAg-negative chronic infection, LHB and MHB were lower than in HBeAg-negative CHB (P < 0.01). ROC analysis identified LHB and MHB as potential discriminators of CHB and chronic infection. LC and HCC exhibited lower LHB, MHB, and MHB/HBsAg than CHB (P < 0.05). Multivariate analysis found that age and the MHB/HBsAg serve as independent factors for the progression of CHB to end stage of liver disease.

CONCLUSIONS

LHB and MHB emerge as novel biomarkers distinguishing chronic infection and CHB. MHB/HBsAg shows promise as a predictor for CHB progression.

An Emerging Animal Model for Querying the Role of Whole Genome Duplication in Development, Evolution, and Disease

Whole genome duplication (WGD) or polyploidization can occur at the cellular, tissue, and organismal levels. At the cellular level, tetraploidization has been proposed as a driver of aneuploidy and genome instability and correlates strongly with cancer progression, metastasis, and the development of drug resistance. WGD is also a key developmental strategy for regulating cell size, metabolism, and cellular function. In specific tissues, WGD is involved in normal development (e.g., organogenesis), tissue homeostasis, wound healing, and regeneration. At the organismal level, WGD propels evolutionary processes such as adaptation, speciation, and crop domestication. An essential strategy to further our understanding of the mechanisms promoting WGD and its effects is to compare isogenic strains that differ only in their ploidy. Caenorhabditis elegans (C. elegans) is emerging as an animal model for these comparisons, in part because relatively stable and fertile tetraploid strains can be produced rapidly from nearly any diploid strain. Here, we review the use of Caenorhabditis polyploids as tools to understand important developmental processes (e.g., sex determination, dosage compensation, and allometric relationships) and cellular processes (e.g., cell cycle regulation and chromosome dynamics during meiosis). We also discuss how the unique characteristics of the C. elegans WGD model will enable significant advances in our understanding of the mechanisms of polyploidization and its role in development and disease.

Chromosome hyperploidy induced by chronic hepatitis B virus infection and its targeted therapeutic strategy

Chronic hepatitis B virus (HBV) infection induces chromosomal hyperploidy (including aneuploidy and polyploidy) and chromosomal instability in hepatocytes, which is one of the main causes of primary hepatocellular carcinoma (HCC). Although hepatocytes can regulate polyploidization of chromosomes under normal conditions, it is difficult to regulate hyperploidization caused by HBV infection and thus carcinogenesis. Studies have shown that HBV can cause dysregulation of many signal pathways such as PLK1/PRC1, and induce chromosome hyperploidy and malignant transformation of hepatocytes. Herein we review the mechanism of HBV infection-induced chromosomal hyperploidy of hepatocytes to cuase hepatocarcinogenesis and the advances in research of drugs targeting chromosomal hyperploidy.

Engineering H2 O2 and O2 Self-Supplying Nanoreactor to Conduct Synergistic Chemiexcited Photodynamic and Calcium-Overloaded Therapy in Orthotopic Hepatic Tumors

Photodynamic therapy (PDT) is traditionally ineffective for deeply embedded tumors due to the poor penetration depth of the excitation light. Chemiluminescence resonance energy transfer (CRET) has emerged as a promising mode of PDT without external light. To date, related research has frequently used endogenous hydrogen peroxide (H₂ O₂ ) and oxygen (O₂ ) inside the solid tumor microenvironment to trigger CRET-mediated PDT. Unfortunately, this significantly restricts treatment efficacy and the development of further biomedical applications because of the limited amounts of endogenous H₂ O₂ and O₂ . Herein, a nanohybrid (mSiO₂ /CaO₂ /CPPO/Ce6: mSCCC) nanoparticle (NP) is designed to achieve synergistic CRET-mediated PDT and calcium (Ca²⁺ )-overload-mediated therapy. The calcium peroxide (CaO₂ ) formed inside mesoporous SiO₂ (mSC) with the inclusion of the chemiluminescent agent (CPPO) and photosensitizer (Ce6) self-supplies H₂ O₂ , O₂ , and Ca²⁺ allowing for the subsequent treatments. The Ce6 in mSCCC NPs is excited by chemical energy in situ following the supply of H₂ O₂ and O₂ to produce singlet oxygen (¹ O₂ ). The nanohybrid NPs are coated with stearic acid to avoid decomposition during blood circulation through contact with aqueous environment. This nanohybrid shows promising performance in the generation of ¹ O₂ for external light-free PDT and the release of Ca²⁺ ions for Ca²⁺ -overloaded therapy against orthotopic hepatocellular carcinoma.

Chemical-induced degradation of PreS2 mutant surface antigen via the induction of microautophagy

Naturally evolved immune-escape PreS2 mutant is an oncogenic caveat of liver cirrhosis and hepatocellular carcinoma (HCC) during chronic hepatitis B virus (HBV) infection. PreS2 mutant is prevalent in above 50% of patients with HCC. In addition, intrahepatic expression of PreS2 mutant large surface antigen (PreS2-LHBS) induces endoplasmic reticulum stress, mitochondria dysfunction, cytokinesis failure, and subsequent chromosome hyperploidy. As PreS2-LHBS has no enzymatic activity, the development of PreS2-specific inhibitors can be challenging. In this study, we aim to identify inhibitors of PreS2-LHBS via the induction of protein-specific degradation. We set up a large-scale protein stability reporter platform and applied an FDA-approved drug library for the screening. We identified ABT199 as a negative modulator of PreS2-LHBS, which induced the degradation of PreS2-LHBS without affecting the general cell viability in both hepatoma and immortalized hepatocytes. Next, by affinity purification screening, we found that PreS2-LHBS interacted with HSC70, a microautophagy mediating chaperone. Simultaneously, inhibitions of lysosomal degradation or microautophagy restored the expression of PreS2-LHBS, suggesting microautophagy is involved in ABT199-induced PreS2-LHBS degradation. Notably, a 24-hr treatment of ABT199 was sufficient for the reduction of DNA damage and cytokinesis failure in PreS2-LHBS expressing hepatocytes. In addition, a persistent treatment of ABT199 for 3 weeks reversed chromosome hyperploidy in PreS2-LHBS cells and suppressed anchorage-independent growth of HBV-positive hepatoma cells. Together, this study identified ABT-199 as a negative modulator of PreS2-LHBS via mediating microautophagy. Our results indicated that long-term inhibition of PreS2-LHBS may serve as a novel strategy for the therapeutic prevention of HBV-mediated HCC.

The Serum Hepatitis B Virus Large Surface Protein as High-Risk Recurrence Biomarker for Hepatoma after Curative Surgery

Chronic hepatitis B (CHB) virus infection is the most important cause of HCC and is also associated with tumor progression. The development of viral biomarkers for HCC prognosis is critical in evaluating relative risks to recurrence in the CHB HCC patients. We report that the large HBV surface protein (LHBS) expression increased in the tumors, implicating that it played a significant role in tumor development. To detect the LHBS in serum and evaluate its association with HCC progression, we developed a sandwich ELISA method for LHBS. The mouse monoclonal antibodies for the pre-S1, pre-S2, and HBS regions were in-house generated and constructed into a chemiluminescent sandwich ELISA system, which allowed sensitive and quantitative measurement of the protein. Using this ELISA assay, we estimated the expression of LHBS in CHB and HCC patients. We found that the serum LHBS level was correlated with the HBS but not the viral titer in serum, indicating that HBV surface proteins’ expression does not mainly depend on viral replication. Moreover, both serum LHBS and HBS levels were lower in the HCC patients than in the CHB. The liver LHBS signals, detected by immunohistochemical staining, showed significant correlations with the serum LHBS and HBS levels. In addition, the more elevated serum LHBS but not HBS level was significantly associated with cirrhosis and worse disease-free and overall survival rates, based on the multivariate analysis. Conclusion: LHBS plays a specific role in tumor progression and is an independent parameter associated with HCC recurrence. Serum LHBS represents a novel noninvasive biomarker for HCC patients with a worse prognosis after surgery.

State of the art treatment of hepatitis B virus hepatocellular carcinoma and the role of hepatitis B surface antigen post-liver transplantation and resection

Chronic hepatitis B virus (HBV) infection is the major aetiology of hepatocellular carcinoma (HCC). The optimal goal of therapy, hepatitis B surface antigen (HBsAg) loss and anti-HBs production, is achieved rarely and HBsAg-associated HCC risk is well recognized. Here we review the role of HBsAg in HCC, the link between HBsAg and HCC recurrence post-liver transplantation or resection, and the implications for therapy. HBV-associated carcinogenesis is a multifactorial process. The observation that HBV-related HCC can occur in the absence of cirrhosis is compatible with a direct oncogenic effect of the virus, which may occur via multiple mechanisms, including those mediated by both mutated and unmutated HBsAg. HCC recurrence in HBsAg-positive patients post-liver transplantation has been reported in 10%-15% of patients and is likely to be because of expansion of residual HCC tumour cell populations containing integrated HBV DNA, which expand and independently replicate HBV, leading to the recurrence of both HCC and HBV. The direct role of HBsAg in HCC recurrence post-liver resection is less clear. Cirrhosis is the most important risk factor for HCC development, and precancerous cirrhotic liver remains after resection, with the potential to undergo malignant transformation regardless of the existence of HBV-derived oncogenic drivers. The role of HBsAg in the development of HCC and its recurrence post-surgical intervention has multiple implications for therapy and suggests a potential role for immunotherapy in the future management of HCC, in particular post-liver transplantation. Use of hepatitis B immunoglobulins that target HBsAg directly, alongside immune-oncology therapies, may be relevant in this setting.

Polyploidy control in hepatic health and disease

A balanced increase in DNA content (ploidy) is observed in some human cell types, including bone-resorbing osteoclasts, platelet-producing megakaryocytes, cardiomyocytes or hepatocytes. The impact of increased hepatocyte ploidy on normal physiology and diverse liver pathologies is still poorly understood. Recent findings suggest swift genetic adaptation to hepatotoxic stress and the protection from malignant transformation as beneficial effects. Herein, we discuss the molecular mechanisms regulating hepatocyte polyploidisation and its implication for different liver diseases and hepatocellular carcinoma. We report on centrosomes' role in limiting polyploidy by activating the p53 signalling network (via the PIDDosome multiprotein complex) and we discuss the role of this pathway in liver disease. Increased hepatocyte ploidy is a hallmark of hepatic inflammation and may play a protective role against liver cancer. Our evolving understanding of hepatocyte ploidy is discussed from the perspective of its potential clinical application for risk stratification, prognosis, and novel therapeutic strategies in liver disease and hepatocellular carcinoma.

Clinical, Pathological and Genetic Characteristics of Pediatric Hepatocellular Carcinoma Associated with Hepatitis B Virus Infection

Introduction

Hepatocellular carcinoma (HCC) remains the major challenge in the management of patients with hepatitis B virus (HBV) infection. To date, limited studies have been done on pediatric HBV-associated HCC specifically.

Methods

Pediatric patients younger than 16 years with HBV-associated HCC were included in the study. HBV integration detection was performed using a high-throughput viral integration detection (HIVID) method.

Results

Among the 13 included pediatric patients, boys predominated (10, 76.9%). The median age at diagnosis of HCC was 13 years and the youngest age was 6 years. Nine patients had initially seronegative hepatitis B e antigen (HBeAg) and 4 had seropositive HBeAg. All patients had cirrhosis and elevated alpha-fetoprotein. Splenomegaly was present in all patients. Intrahepatic HBsAg was not detected in any tumor tissues from 5 patients who underwent biopsy or excision, while it was positive in all matched non-tumor tissues. In the tumor and matched non-tumor tissues from 3 individuals, HBV integration was identified except in the neoplastic specimen from 1 patient. Integration into the reported genes associated with hepatocarcinogenesis was not found in the tumor tissues from the 3 patients.

Discussion

Hypervigilance for HCC development is required in HBeAg-negative cirrhotic children. The findings based on the immunohistochemical and genetic results expand the knowledge of pediatric HCC development.

Hepatitis B Virus Pre-S Gene Deletions and Pre-S Deleted Proteins: Clinical and Molecular Implications in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most frequent and fatal human cancers worldwide and its development and prognosis are intimately associated with chronic infection with hepatitis B virus (HBV). The identification of genetic mutations and molecular mechanisms that mediate HBV-induced tumorigenesis therefore holds promise for the development of potential biomarkers and targets for HCC prevention and therapy. The presence of HBV pre-S gene deletions in the blood and the expression of pre-S deleted proteins in the liver tissues of patients with chronic hepatitis B and HBV-related HCC have emerged as valuable biomarkers for higher incidence rates of HCC development and a higher risk of HCC recurrence after curative surgical resection, respectively. Moreover, pre-S deleted proteins are regarded as important oncoproteins that activate multiple signaling pathways to induce DNA damage and promote growth and proliferation in hepatocytes, leading to HCC development. The signaling molecules dysregulated by pre-S deleted proteins have also been validated as potential targets for the prevention of HCC development. In this review, we summarize the clinical and molecular implications of HBV pre-S gene deletions and pre-S deleted proteins in HCC development and recurrence and highlight their potential applications in HCC prevention and therapy.

Lipid Storage and Interferon Response Determine the Phenotype of Ground Glass Hepatocytes in Mice and Humans

BACKGROUND AND AIMS

A histopathological hallmark of chronic hepatitis B virus (HBV) infection is the presence of ground glass hepatocytes (GGHs). GGHs are liver cells that exhibit eosinophilic, granular, glassy cytoplasm in light microscopy and are characterized by accumulation of HBV surface (HBs) proteins in the endoplasmic reticulum (ER). More important, GGHs have been accepted as a precursor of HCC and may represent preneoplastic lesions of the liver.

METHODS

Here we show that the reason for ground glass phenotype of hepatocytes in patients with chronic hepatitis B (CHB) and in HBs transgenic mice is a complex formation between HBs proteins and lipid droplets (LDs) within the ER.

RESULTS

As fat is a main component of LDs their presence reduces the protein density of HBs aggregates. Therefore, they adsorb less amount of eosin during hematoxylin-eosin staining and appear dull in light microscopy. However, after induction of interferon response in the liver LDs were not only co-localized with HBs but also distributed throughout the cytoplasm of hepatocytes. The uniform distribution of LDs weakens the contrast between HBs aggregates and the rest of the cytoplasm and complicates the identification of GGHs. Suppression of interferon response restored the ground glass phenotype of hepatocytes.

CONCLUSIONS

Complex formation between HBs and LDs represents a very important feature of CHB that could affect LDs functions in hepatocytes. The strain specific activation of the interferon response in the liver of HBs/c mice prevented the development of GGHs. Thus, manipulation of LDs could provide a new treatment strategy in the prevention of liver cancer.

Aerobic glycolysis supports hepatitis B virus protein synthesis through interaction between viral surface antigen and pyruvate kinase isoform M2

As an intracellular pathogen, the reproduction of the hepatitis B virus (HBV) depends on the occupancy of host metabolism machinery. Here we test a hypothesis if HBV may govern intracellular biosynthesis to achieve a productive reproduction. To test this hypothesis, we set up an affinity purification screen for host factors that interact with large viral surface antigens (LHBS). This identified pyruvate kinase isoform M2 (PKM2), a key regulator of glucose metabolism, as a binding partner of viral surface antigens. We showed that the expression of viral LHBS affected oligomerization of PKM2 in hepatocytes, thereby increasing glucose consumption and lactate production, a phenomenon known as aerobic glycolysis. Reduction of PKM2 activity was also validated in several different models, including HBV-infected HepG2-NTCP-C4 cells, adenovirus mediated HBV gene transduction and transfection with a plasmid containing complete HBV genome on HuH-7 cells. We found the recovery of PKM2 activity in hepatocytes by chemical activators, TEPP-46 or DASA-58, reduced expressions of viral surface and core antigens. In addition, reduction of glycolysis by culturing in low-glucose condition or treatment with 2-deoxyglucose also decreased expressions of viral surface antigen, without affecting general host proteins. Finally, TEPP-46 largely suppressed proliferation of LHBS-positive cells on 3-dimensional agarose plates, but showed no effect on the traditional 2-dimensional cell culture. Taken together, these results indicate that HBV-induced metabolic switch may support its own translation in hepatocytes. In addition, aerobic glycolysis is likely essential for LHBS-mediated oncogenesis. Accordingly, restriction of glucose metabolism may be considered as a novel strategy to restrain viral protein synthesis and subsequent oncogenesis during chronic HBV infection.

A Rapid Immunochromatographic Method Based on a Secondary Antibody-Labelled Magnetic Nanoprobe for the Detection of Hepatitis B preS2 Surface Antigen

Hepatitis B is a globally prevalent viral infectious disease caused by the hepatitis B virus (HBV). In this study, an immunochromatographic assay (ICA) for the rapid detection of hepatitis B preS2 antigen (preS2Ag) was established. The magnetic nanoparticles (MNPs) indirectly labelled with goat anti-mouse (GAM) secondary antibody were applied as a nanoprobe for free preS2 antibody (preS2Ab) capturing and signal amplification. By employing sample pre-incubation processing as well, preS2Ag-preS2Ab was sufficiently caught by the GAM-MNPs probe in 5 min. A qualitative sensitivity of 625 ng/mL was obtained by naked-eye observation within 15-20 min. A standard curve (0-5000 ng/mL) was established, with a quantitative limit of detection (LOD) of 3.6 ng/mL, based on the stability and penetrability of the magnetic signal characteristics. The proposed method for preS2Ag was rapid (~25 min, cf. ELISA ~4 h) and had a good accuracy, which was verified using an ELISA kit (relative error < 15%). Large equipment and skilled technicians were not required. The sensitivity and specificity of the developed GAM-MNPs-ICA method were 93.3% and 90% in clinical serum samples (n = 25), respectively. A good detection consistency (84%) was observed between the developed ICA method and 2 types of commercial ELISA kits, indicating that the GAM-MNPs-ICA has a potential application in large-scale screening for and point-of-care diagnosis of hepatitis B or other infectious diseases.

Polyploid Giant Cancer Cells, a Hallmark of Oncoviruses and a New Therapeutic Challenge

Tumors are renowned as intricate systems that harbor heterogeneous cancer cells with distinctly diverse molecular signatures, sizes and genomic contents. Among those various genomic clonal populations within the complex tumoral architecture are the polyploid giant cancer cells (PGCC). Although described for over a century, PGCC are increasingly being recognized for their prominent role in tumorigenesis, metastasis, therapy resistance and tumor repopulation after therapy. A shared characteristic among all tumors triggered by oncoviruses is the presence of polyploidy. Those include Human Papillomaviruses (HPV), Epstein Barr Virus (EBV), Hepatitis B and C viruses (HBV and HCV, respectively), Human T-cell lymphotropic virus-1 (HTLV-1), Kaposi's sarcoma herpesvirus (KSHV) and Merkel polyomavirus (MCPyV). Distinct viral proteins, for instance Tax for HTLV-1 or HBx for HBV have demonstrated their etiologic role in favoring the appearance of PGCC. Different intriguing biological mechanisms employed by oncogenic viruses, in addition to viruses with high oncogenic potential such as human cytomegalovirus, could support the generation of PGCC, including induction of endoreplication, inactivation of tumor suppressors, development of hypoxia, activation of cellular senescence and others. Interestingly, chemoresistance and radioresistance have been reported in the context of oncovirus-induced cancers, for example KSHV and EBV-associated lymphomas and high-risk HPV-related cervical cancer. This points toward a potential linkage between the previously mentioned players and highlights PGCC as keystone cancer cells in virally-induced tumors. Subsequently, although new therapeutic approaches are actively needed to fight PGCC, attention should also be drawn to reveal the relationship between PGCC and oncoviruses, with the ultimate goal of establishing effective therapeutic platforms for treatment of virus-associated cancers. This review discusses the presence of PGCCs in tumors induced by oncoviruses, biological mechanisms potentially favoring their appearance, as well as their consequent implication at the clinical and therapeutic level.

Polyploidy: A Biological Force From Cells to Ecosystems

Polyploidy, resulting from the duplication of the entire genome of an organism or cell, greatly affects genes and genomes, cells and tissues, organisms, and even entire ecosystems. Despite the wide-reaching importance of polyploidy, communication across disciplinary boundaries to identify common themes at different scales has been almost nonexistent. However, a critical need remains to understand commonalities that derive from shared polyploid cellular processes across organismal diversity, levels of biological organization, and fields of inquiry - from biodiversity and biocomplexity to medicine and agriculture. Here, we review the current understanding of polyploidy at the organismal and suborganismal levels, identify shared research themes and elements, and propose new directions to integrate research on polyploidy toward confronting interdisciplinary grand challenges of the 21^st century.

Antiviral activity of PLK1-targeting siRNA delivered by lipid nanoparticles in HBV-infected hepatocytes

BACKGROUND

A link between HBV and PLK1 was clearly evidenced in HBV-driven carcinogenesis, and we have also recently shown that PLK1 is a proviral factor in the early phases of HBV infection. Moreover, we have shown that BI-2536, a small molecule PLK1 inhibitor, was very efficient at inhibiting HBV DNA neosynthesis, notably by affecting nucleocapsid assembly as a result of the modulation of HBc phosphorylation. Yet, as small molecule kinase inhibitors often feature poor selectivity, a more specific and safer strategy to target PLK1 would be needed for a potential development against chronic HBV infections.

METHODS

Here, we analysed using both freshly isolated primary human hepatocytes and differentiated HepaRG, the anti-HBV properties of an LNP-encapsulated PLK1-targeting siRNA. Standard assays were used to monitor the effect of LNP siPLK1, or controls (LNP siHBV and LNP siNon-targeting), on HBV replication and cell viability.

RESULTS

A dose as low as 100 ng/ml of LNP-siPLK1 resulted in a >75% decrease in secreted HBV DNA (viral particles), which was comparable to that obtained with LNP siHBV or 10 µM of tenofovir (TFV), without affecting cell viability. Interestingly, and in contrast to that obtained with TFV, a strong inhibition of viral RNA and HBe/HBsAg secretions was also observed under LNP siPLK1 treatment. This correlated with a significant intracellular decrease of vRNA accumulation, which was independent of any change in cccDNA levels, thus suggesting a transcriptional or post-transcriptional modulation. Such an effect was not obtained with a biochemical approach of PLK1 inhibition, suggesting an enzymatic-independent role of PLK1.

CONCLUSIONS

This study emphasizes that a specific PLK1 inhibition could help in achieving an improved HBsAg loss in CHB patients, likely in combination with other HBsAg-targeting strategies.

Aneuploidy and oncoviruses

Seven oncogenic viruses are known for tumorigenesis and contribute to 12% of all human cancers. The oncogenic factors, the target tissue, and pathology of cancer vary among these viruses with several mechanisms proposed for the initiation and development of cancer. Aneuploidy in cells is associated with anomalies in chromosome number that can be a hallmark of cancer, a disease defined by expanded proliferative potential. In this review, we summarize the different mechanisms of aneuploidy and furthermore discuss recent findings of the role of viral oncoproteins in inducing cellular aneuploidy that might facilitate tumorigenesis. Improved understanding of viral oncogenesis may help to find new strategies for controlling virus-associated cancers.

Chemopreventive Effect of Phytosomal Curcumin on Hepatitis B Virus-Related Hepatocellular Carcinoma in A Transgenic Mouse Model

Chronic hepatitis B virus (HBV) infection is a major risk factor for the development of hepatocellular carcinoma (HCC), a leading cause of cancer mortality worldwide. Hepatitis B X protein (HBx) and pre-S2 mutant have been proposed as the two most important HBV oncoproteins that play key roles in HCC pathogenesis. Curcumin is a botanical constituent displaying potent anti-inflammatory and anti-cancer properties without toxic side effects. Phytosomal formulation of curcumin has been shown to exhibit enhanced bioavailability, improved pharmacokinetics, and excellent efficacy against many human diseases. However, effectiveness of phytosomal curcumin for HCC treatment remains to be clarified. In this study, we evaluated chemopreventive effect of phytosomal curcumin on HBV-related HCC by using a transgenic mouse model specifically expressing both HBx and pre-S2 mutant in liver. Compared with unformulated curcumin, phytosomal curcumin exhibited significantly greater effects on suppression of HCC formation, improvement of liver histopathology, decrease of lipid accumulation and leukocyte infiltration, and reduction of total tumor volume in transgenic mice. Moreover, phytosomal curcumin exerted considerably stronger effects on activation of anti-inflammatory PPARγ as well as inhibition of pro-inflammatory NF-κB than unformulated curcumin. Furthermore, phytosomal curcumin showed a comparable effect on suppression of oncogenic mTOR activation to unformulated curcumin. Our data demonstrated that phytosomal curcumin has promise for HCC chemoprevention in patients with chronic HBV infection.

Hepatitis B virus large surface protein is priming for hepatocellular carcinoma development via induction of cytokinesis failure

Chronic hepatitis B virus (HBV) infection is a main risk factor for development of liver cirrhosis and hepatocellular carcinoma (HCC). Although HBV vaccination and antiviral therapy lead to substantial risk reduction for HCC development, it is evident that both can reduce, but not completely eliminate the risk. High serum levels of HBV surface antigen (HBsAg) were shown to predict disease progression of chronic HBV infection in patients harboring low viral load, and in line with this, HBV surface proteins were shown to exert oncogenic functions. As HBsAg seroclearance is infrequently achieved in patients who have undergone antiviral therapy, it is necessary to gain further insights into molecular mechanisms of HBsAg seroclearance failure after antiviral therapy and HCC development mediated by HBV surface proteins. A recent study published in this journal has shown that the HBsAg large surface protein (LHBs) contributes to HCC development by inducing cytokinesis failure and consequent aneuploidy via induction of DNA damage and polo-like kinase 1 (PLK1)-mediated G2/M checkpoint failure in hepatocytes. Inhibition of PLK1 by a PLK1-specific small molecule inhibitor was shown to restore G2/M checkpoint in vitro and to reduce tumor burden in vivo. The initial LHBs-induced hepatocyte aneuploidy may give rise to further aneuploidy and thereby lead to self-propagating cycles of chromosomal instability driving intra-tumor heterogeneity and clonal cancer evolution. Thus, LHBs-induced cytokinesis failure may be a priming event for HCC development. In conclusion, the study not only provides further mechanistic insights into the oncogenic role of LHBs, but also identifies a potential target to interfere with the vicious circle of LHBs-induced aneuploidy, which may be especially useful in patients showing failure of HBsAg seroclearance after antiviral therapy. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.