Malignant Transformation Of Hepatocytes Research Articles

Early monitoring values of oncogenic signalling molecules for hepatocellular carcinoma.

The prevention and early diagnosis of liver cancer remains a global medical challenge. During the malignant transformation of hepatocytes, a variety of oncogenic cellular signalling molecules, such as novel high mobility group-Box 3, angiopoietin-2, Golgi protein 73, glypican-3, Wnt3a (a signalling molecule in the Wnt/β-catenin pathway), and secretory clusterin, can be expressed and secreted into the blood. These signalling molecules are derived from different signalling pathways and may not only participate in the malignant transformation of hepatocytes but also become early diagnostic indicators of hepatocarcinogenesis or specific targeted molecules for hepatocellular carcinoma therapy. This article reviews recent progress in the study of several signalling molecules as sensitive biomarkers for monitoring hepatocarcinogenesis.

Abstract 4412: Defining chromatin alterations in liver cancer at single cell resolution

Abstract Hepatocellular carcinoma (HCC) is the most common liver cancer and arises from the malignant transformation of hepatocytes. HCC tumors often express genes critical for hepatocyte development but the regulatory mechanisms driving aberrant expression remain unclear. Recent evidence indicates that epigenetic alterations contribute to HCC progression with nearly 50% of cases associated with mutations in chromatin modifiers. Thus, it is imperative to understand how chromatin is altered in HCC and identify the DNA regulatory sequences associated with HCC tumorigenesis. Our study aims to map the chromatin landscape and transcriptome in HCC tumors using a multiomic approach at single cell resolution. Single-cell ATAC- and RNA-seq will be conducted in HCC tumors, matched controls and normal livers to identify regulatory sequences and their target genes critical for HCC tumor progression. We will characterize these regulatory sequences in the context of liver development using genetic manipulation and epigenomic datasets generated from human pluripotent stem cells differentiated to hepatic lineages. Our goal is to elucidate how epigenetic alterations in HCC drive cancer progression and how they relate to a dedifferentiated state. Citation Format: Miguel Ramirez, Tabea Stephan, Daivd Schaeffer, Pamela Hoodless. Defining chromatin alterations in liver cancer at single cell resolution [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4412.

Circadian dysfunction induces NAFLD-related human liver cancer in a mouse model

Chronic circadian dysfunction increases the risk of non-alcoholic fatty liver disease (NAFLD)-related hepatocellular carcinoma (HCC), but the underlying mechanisms and direct relevance to human HCC have not been established. In this study, we aimed to determine whether chronic circadian dysregulation can drive NAFLD-related carcinogenesis from human hepatocytes and human HCC progression. Chronic jet lag of mice with humanized livers induces spontaneous NAFLD-related HCCs from human hepatocytes. The clinical relevance of this model was analysed by biomarker, pathological/histological, genetic, RNA sequencing, metabolomic, and integrated bioinformatic analyses. Circadian dysfunction induces glucose intolerance, NAFLD-associated human HCCs, and human HCC metastasis independent of diet in a humanized mouse model. The deregulated transcriptomes in necrotic-inflammatory humanized livers and HCCs bear a striking resemblance to those of human non-alcoholic steatohepatitis (NASH), cirrhosis, and HCC. Stable circadian entrainment of hosts rhythmically paces NASH and HCC transcriptomes to decrease HCC incidence and prevent HCC metastasis. Circadian disruption directly reprogrammes NASH and HCC transcriptomes to drive a rapid progression from hepatocarcinogenesis to HCC metastasis. Human hepatocyte and tumour transcripts are clearly distinguishable from mouse transcripts in non-parenchymal cells and tumour stroma, and display dynamic changes in metabolism, inflammation, angiogenesis, and oncogenic signalling in NASH, progressing to hepatocyte malignant transformation and immunosuppressive tumour stroma in HCCs. Metabolomic analysis defines specific bile acids as prognostic biomarkers that change dynamically during hepatocarcinogenesis and in response to circadian disruption at all disease stages. Chronic circadian dysfunction is independently carcinogenic to human hepatocytes. Mice with humanized livers provide a powerful preclinical model for studying the impact of the necrotic-inflammatory liver environment and neuroendocrine circadian dysfunction on hepatocarcinogenesis and anti-HCC therapy. Human epidemiological studies have linked chronic circadian dysfunction to increased hepatocellular carcinoma (HCC) risk, but direct evidence that circadian dysfunction is a human carcinogen has not been established. Here we show that circadian dysfunction induces non-alcoholic steatohepatitis (NASH)-related carcinogenesis from human hepatocytes in a murine humanized liver model, following the same molecular and pathologic pathways observed in human patients. The gene expression signatures of humanized HCC transcriptomes from circadian-disrupted mice closely match those of human HCC with the poorest prognostic outcomes, while those from stably circadian entrained mice match those from human HCC with the best prognostic outcomes. Our studies establish a new model for defining the mechanism of NASH-related HCC and highlight the importance of circadian biology in HCC prevention and treatment.

When does hepatitis B virus meet long-stranded noncoding RNAs?

Hepatitis B virus (HBV) infection in humans and its associated diseases are long-standing problems. HBV can produce a large number of non-self-molecules during its life cycle, which acts as targets for innate immune recognition and initiation. Among these, interferon and its large number of downstream interferon-stimulated gene molecules are important early antiviral factors. However, the development of an effective antiviral immune response is not simple and depends not only on the delicate regulation of the immune response but also on the various mechanisms of virus-related immune escape and immune tolerance. Therefore, despite there being a relatively well-established consensus on the major pathways of the antiviral response and their component molecules, the complete clearance of HBV remains a challenge in both basic and clinical research. Long-noncoding RNAs (lncRNAs) are generally >200 bp in length and perform different functions in the RNA strand encoding the protein. As an important part of the IFN-inducible genes, interferon-stimulated lncRNAs are involved in the regulation of several HBV infection-related pathways. This review traces the basic elements of such pathways and characterizes the various recent targets of lncRNAs, which not only complement the regulatory mechanisms of pathways related to chronic HBV infection, fibrosis, and cancer promotion but also present with new potential therapeutic targets for controlling HBV infection and the malignant transformation of hepatocytes.

Liver Imaging Reporting and Data System criteria for the diagnosis of hepatocellular carcinoma in clinical practice: A pictorial minireview.

Hepatocellular carcinoma (HCC) is the sixth most common cancer. The main risk factors associated with HCC development include hepatitis B virus, hepatitis C virus, alcohol consumption, aflatoxin B1, and nonalcoholic fatty liver disease. However, hepatocarcinogenesis is a complex multistep process. Various factors lead to hepatocyte malignant transformation and HCC development. Diagnosis and surveillance of HCC can be made with the use of liver ultrasound (US) every 6 mo. However, the sensitivity of this imaging method to detect HCC in a cirrhotic liver is limited, due to the abnormal liver parenchyma. Computed tomography (CT) and magnetic resonance imaging (MRI) are considered to be most useful tools for at-risk patients or patients with inadequate US. Liver biopsy is still used for diagnosis and prognosis of HCC in specific nodules that cannot be definitely characterized as HCC by imaging. Recently the American College of Radiology designed the Liver Imaging Reporting and Data System (LI-RADS), which is a comprehensive system for standardized interpretation of CT and MRI liver examinations that was first proposed in 2011. In 2018, it was integrated into the American Association for the Study of Liver Diseases guidance statement for HCC. LI-RADS is designed to ensure high sensitivity, precise categorization, and high positive predictive value for the diagnosis of HCC and is applied to “high-risk populations” according to specific criteria. Most importantly LI-RADS criteria achieved international collaboration and consensus among liver experts around the world on the best practices for caring for patients with or at risk for HCC.

Abstract 3746: Influence of diethylnitrosamine on Mucin 13 expression in hepatocellular carcinoma

Abstract Background: Hepatocellular carcinoma (HCC) is regarded as environmental-related cancer due to involvement of chemical carcinogen and viral components in multistage process. Accumulating studies have shown that obesity and non-alcoholic fatty liver disease, which can lead to HCC, have been linked to modern diets that are high in fat and charcoal-grilled processed meat, however, the exact processes through which diet contributes to hepato-carcinogenesis remain unclear. In the present study, we demonstrated that diethylnitrosamine (DEN), a subgroup of the N-nitroso compounds presents in food additive/preservative, tobacco smoke, and pharmaceutical products, upregulates the Mucin 13, transmembrane mucin, via miR-145 suppression accompanied by hepatocarcinogenesis events. Methodology: Western blotting and qPCR were performed to examine the treatment effects of DEN on Mucin 13 and associated effector proteins in hepatocellular carcinoma cell (HepG2, Hep3B, C3A, and SK-HEP-1) lines. Chemically induced (DEN; 200 mg/kg bw; 2-AAF (150 mg/kg bw) animal model was used to further investigate the Mucin 13 expression. The serum AST, ALT and ALP activity were measured using kits provided by Span diagnostics. Immunohistochemistry was used to stain tumor tissue sections for Mucin 13 expression, and in situ hybridization was performed to detect miR-145 levels. Molecular docking studies were performed using Auto dock 4 package. Results: Our study demonstrated that DEN treatment facilitates the DNA adducts formation in liver cancer cell lines as compared to vehicle controls. Moreover, DEN treatment upregulates Mucin 13 and associated effector proteins as analyzed by qPCR and Western blotting. Liver section of DEN+2-AAF-administered group showed vacuolization of hepatocytes in the centrizonal area with variation of nuclear size. Clear nuclear atypia in the adenoma was seen. The serum activities of AST, ALP and ALT in diseased animals correlated with the liver cancer progression. Additionally, Mucin 13 was also upregulated by DEN treatment in liver tissues. Intriguingly, nuclear Mucin 13 staining was very less in normal liver tissues, whereas its levels were significantly increased DEN+2-AAF induced HCC. These observations indicate that nuclear localization of Mucin 13 may contribute to the malignant transformation of hepatocytes during carcinogenesis. This revealed significant downregulation of tumor suppressors miR-145 in tumor tissues as compared to normal control. Molecular modelling analysis revealed that DEN interacts with Mucin 13 and forms a stable complex by offering numerous interactions with the residues of Mucin 13. Conclusions: We propose that DEN modulates Mucin 13 and associated effector proteins in hepatocarcinogenesis. Citation Format: Shabnam Malik, Mohammed Sikander, Parvez Khan, Murali M. Yallapu, Swatantra Jain, Deepshikha P. Katare, Subhash C. Chauhan, Meena Jaggi. Influence of diethylnitrosamine on Mucin 13 expression in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3746.

Encouraging specific biomarkers-based therapeutic strategies for hepatocellular carcinoma.

The prevention, early discovery and effective treatment of patients with hepatocellular carcinoma (HCC) remain a global medical challenge. At present, HCC is still mainly treated by surgery, supplemented by vascular embolization, radio frequency, radiotherapy, chemotherapy and biotherapy. The application of multikinase inhibitor sorafenib, chimeric antigen receptor T cells, or PD-1/PD-L1 inhibitors can prolong the median survival of HCC patients. However, the treatment efficacy is still unsatisfactory due to HCC metastasis and postoperative recurrence. During the process of hepatocyte malignant transformation, HCC tissues can express and secrete many types of specific biomarkers, or oncogenic antigen molecules into blood, for example, alpha-fetoprotein, glypican-3, Wnt3a (one of the key signaling molecules in the Wnt/β-catenin pathway), insulin-like growth factor (IGF)-II or IGF-I receptor, vascular endothelial growth factor, secretory clusterin and so on. In addition, combining immunotherapy with non-coding RNAs might improve anti-cancer efficacy. These biomarkers not only contribute to HCC diagnosis or prognosis, but may also become molecular targets for HCC therapy under developing or clinical trials. This article reviews the progress in emerging biomarkers in basic research or clinical trials for HCC immunotherapy.

Tumor Microenvironment: Necroptosis Switches the Subtype of Liver Cancer While Necrosis Promotes Tumor Recurrence and Progression.

Liver cancer is a heterogeneous group of solid tumors that include mainly epithelial tumors. As with other solid carcinomas, tumor development results from an accumulation of genetic and epigenetic alterations. Hepatocellular carcinoma and intrahepatic cholangiocarcinoma, derived from malignant transformation of hepatocytes and cholangiocytes, respectively, are 2 primary types of liver cancers. However, it has been shown that the same kind of cell can give rise to different types of cancer, depending on manner of cell death in the tumor microenvironment. In a recent animal study, hepatocytes gave rise to both hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Oncogenically activated hepatocytes were shown to give rise to intrahepatic cholangiocarcinoma or hepatocellular carcinoma depending on cell death type of neighboring cells. Hepatocytes within the necroptotic microenvironment gave rise to intrahepatic cholangiocarcinoma; however, hepatocytes harboring the same oncogenic driver gave rise to hepatocellular carcinoma within the apoptotic microenvironment. The hepatic cytokine microenvironment structured by the necroptosis can also switch hepatocellular carcinoma to intrahepatic cholangiocarcinoma independently of the oncogenic drivers. Cell death by necrosis in damaged livers can also lead to development of carcinoma. Cancer cells are known to be resistant to apoptosis as a result of p53 mutation. Therefore, necrosis is the primary cell death pathway in cancer therapy. Necrosis is associated with high levels of angiogenesis, tumor-associated macrophages, and increased inflammation in the tumor microenvironment. Patients with hepatocellular carcinoma or intrahepatic cholangiocarcinoma characterized by necrosis and tumor-associated macrophages have reduced overall survival and recurrence-free survival. Cytotoxicity from anticancer therapy can also lead to accelerated necrosis. The content of cells undergoing necrosis triggers cytokine secretion, which designs cancer progression via inflammatory and noninflammatory pathways. Thus, the tumor microenvironment and manner of cell death (necrosis, apoptosis, or necroptosis) are crucial factors in the development of primary liver cancers and tumor progression.

Tumor suppressive role of mitochondrial sirtuin 4 in induction of G2/M cell cycle arrest and apoptosis in hepatitis B virus-related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is developed from uncontrolled cell growth after the malignant transformation of hepatocytes. The hepatitis B virus (HBV) X protein (HBx) has shown to induce cell cycle progression and hepatocarcinogenesis. A sub-fraction of HBx is localized in the mitochondria. Sirtuin 4 (SIRT4), a mitochondrial protein, has been demonstrated to play a tumor-suppressive role in many cancers, including HCC. However, little is known about the association between mitochondrial HBx and SIRT4 during hepatocarcinogenesis. We aimed to investigate the clinical significance and functional role of SIRT4 in HBV-related HCC. SIRT4 expression was significantly lower in the HCC tissues collected from 30 patients with HBV-related HCC than in normal liver tissues from control patients (p < 0.0001). TCGA data analysis indicated that SIRT4 expression was also lower in patients with HBV infection than in those without, and SIRT4 levels were positively associated with better patient survival. Similarly, HCC cell lines had lower SIRT4 expression than normal liver cell lines (all p < 0.01). Among the HCC cell lines, those harbored HBV had a lower SIRT4 expression than those without HBV (p < 0.0001). In vitro experiments revealed that stable HBx transfection suppressed SIRT4 expression in both HepG2 and Huh7 cells (both p < 0.001). Ectopic SIRT4 overexpression alone could induce cellular senescence through arresting cell-cycle progression at G2/M, and inducing cell apoptosis in HCC cells. Mechanistically, SIRT4 upregulated cell-cycle governing genes p16 and p21 protein expression, suppressed CyclinB1/Cdc2 and Cdc25c which normally induce cell-cycle progression, and suppressed survivin to induce apoptosis. Our findings demonstrate the interaction between HBV and SIRT4 in the context of HCC. SIRT4 involves in G2/M DNA damage checkpoint control and genomic stability in hepatocarcinogenesis, which could be targeted for future anticancer strategies.

Effects of alpha-fetoprotein on the occurrence and progression of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. Alpha-fetoprotein (AFP) is considered as a diagnostic and prognostic tumorous marker for HCC, and up to 70% of HCC patients showed elevated serum levels of AFP. In the past two decades, evidences have shown that AFP not only is a tumorous biomarker for diagnosing HCC, but also plays a very complicated role in regulating proliferation, apoptosis, and autophagy and inhibiting the immune response of cells. Because AFP is significantly elevated during hepatocarcinogenesis, the role of AFP in the development of HCC is a scientific problem worthy of further exploration. In this review, we reviewed the effects of AFP on hepatocyte malignant transformation and the underlying mechanisms involved in the progression of HCC.

Abnormal CD44 activation of hepatocytes with nonalcoholic fatty accumulation in rat hepatocarcinogenesis.

BACKGROUNDPrevalence of nonalcoholic fatty liver disease (NAFLD) is rapidly increasing, and NAFLD has become one of the most common chronic liver diseases worldwide. With abnormal CD44 activation, the severe form of NAFLD can progress to liver cirrhosis and hepatocellular carcinoma (HCC). Thus, the molecular mechanism of CD44 in NAFLD needs to be identified.AIMTo investigate the relationship between CD44 activation and malignant transformation of rat hepatocytes under nonalcoholic lipid accumulation.METHODSSprague-Dawley rats were fed a high-fat (HF) for 12 wk to entice NAFLD and then with HF plus 2-fluorenylacetamide (0.05%) to induce HCC. Rats were sacrificed every 2 wk, and subsequently divided into the groups based on liver pathological examination (hematoxylin and eosin staining): NAFLD, denaturation, precancerosis, HCC, and control. Liver CD44 mRNA was detected by OneArray. Liver fat as assessed by Oil red O staining or CD44 by immunohistochemical assay was compared with their integral optic density. Serum CD44, alanine aminotransferase, aspartate aminotransferase, triglyceride, total cholesterol, and AFP levels were quantitatively tested.RESULTSElevated CD44 was first reported in hepatocarcinogenesis, with increasing expression from NAFLD to HCC at the protein or mRNA level. The CD44 integral optic density values were significantly different between the control group and the NAFLD (t = 25.433, P < 0.001), denaturation (t = 48.822, P < 0.001), precancerosis (t = 27.751, P < 0.001), and HCC (t = 16.239, P < 0.001) groups, respectively. Hepatic CD44 can be secreted into the blood, and serum CD44 levels in HCC or precancerous rats were significantly higher (P < 0.001) than those in any of the other rats. Positive correlations were found between liver CD44 and CD44 mRNA (rs = 0.373, P = 0.043) and serum CD44 (rs = 0.541, P = 0.002) and between liver CD44 mRNA and serum CD44 (rs = 0.507, P = 0.004). Moreover, significant correlations were found between liver CD44 and liver AFP (rs = 0.572, P = 0.001), between serum CD44 and serum AFP (rs = 0.608, P < 0.001), and between CD44 mRNA and AFP mRNA (rs = 0.370, P = 0.044).CONCLUSIONThe data suggested that increasing CD44 expression is associated with the malignant transformation of hepatocytes in NAFLD.

Insulin-like Growth Factor I Receptor: A Novel Target for Hepatocellular Carcinoma Gene Therapy.

Human insulin-like growth factor (IGF) axis affects the molecular pathogenesis of hepatocellular carcinoma (HCC), especially in the abnormality of hepatic IGF-I receptor (IGF-IR) or IGF-II expression as a key molecule in hepatocarcinogenesis. However, the over-expression of hepatic IGFIR is associated with HCC progression with largely unknown mechanisms. The IGF-IR as one key molecule of the IGF signal pathway plays an important role in the hepatocyte malignant transformation. Attaching importance to IGF-IR might improve the prognostic or the therapeutic technique of HCC. This article reviews IGF-IR alteration during HCC development, and the effects of silencing IGF-IR gene by specific short hairpin RNA on the inhibition of cell proliferation in vitro or HCC xenograft growth in vivo to elucidate it as a novel molecular-targeted therapy for HCC.

Alteration of oncogenic IGF-II gene methylation status associates with hepatocyte malignant transformation

BackgroundOncogenic insulin-like growth factor-II (IGF-II) is overexpressed in hepatocellular carcinoma (HCC). The present study aimed to analyze the dynamic alteration of IGF-II CpG site methylation status and its molecular mechanism in HCC progression. MethodsIGF-II alterations were observed in rat hepatocarcinogenesis models induced by 2-acetylaminofluorene. Liver IGF-II expression was compared by immunohistochemistry or tissue IGF-II specific concentration (nmol/mg protein). Status of human IGF-II promoter 3 (P3) or rat IGF-II P2 CpG site methylation was amplified by methylation-specific polymerase chain reaction (MSP). Serum IGF-II levels were quantitatively detected by an enzyme-linked immunosorbent assay. ResultsThe levels of hepatic IGF-II expression were significantly elevated in the HCC group (P < 0.001). The unmethylation rate of IGF-II P3 CpG sites was 100% in the HCC-, 52.5% in the paracancerous-, and none (0%) in the distal noncancerous-tissues. Abnormal IGF-II expression was related to differentiation degree, tumor invasion, and positive HBV-DNA (all P < 0.001), with a negative correlation between P3 methylation degree and IGF-II expression. There was a positive correlation between liver IGF-II specific concentration and circulating IGF-II level (r = 0.97, P < 0.001). Significantly negative correlation was found between IGF-II P2 CpG site methylation and circulating IGF-II (rs = −0.89, P < 0.001) or liver IGF-II level (rs = −0.84, P < 0.001). ConclusionsThe increase of serum IGF-II and the alteration of oncogenic gene IGF-II methylation may be biomarkers for HCC diagnosis and DNA methylation may be the therapeutic target of HCC.

Extracellular Vesicles in Hepatobiliary Malignancies.

Primary hepatobiliary malignancies include a heterogeneous group of cancers with dismal prognosis, among which hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and hepatoblastoma (HB) stand out. These tumors mainly arise from the malignant transformation of hepatocytes, cholangiocytes (bile duct epithelial cells) or hepatoblasts (embryonic liver progenitor cells), respectively. Early diagnosis, prognosis prediction and effective therapies are still a utopia for these diseases. Extracellular vesicles (EVs) are small membrane-enclosed spheres secreted by cells and present in biological fluids. They contain multiple types of biomolecules, such as proteins, RNA, DNA, metabolites and lipids, which make them a potential source of biomarkers as well as regulators of human pathobiology. In this review, the role of EVs in the pathogenesis of hepatobiliary cancers and their potential usefulness as disease biomarkers are highlighted. Moreover, the therapeutic value of EV regulation is discussed and future directions on basic and clinical research are indicated.

Abnormal expression of HMGB-3 is significantly associated with malignant transformation of hepatocytes.

AIMTo explore the relationship between dynamic expression of high mobility group box-3 (HMGB3) and malignant transformation of hepatocytes.METHODSExpression of HMGB family proteins were observed in rat hepatocarcinogenesis models induced with 2-acetylaminofluorene. Alterations of HMGB3 were analyzed at the mRNA level by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and at the protein level by immunohistochemistry or Western blotting. HMGB3 in human liver cancer tissues were evaluated using bioinformatics databases from GEO, TCGA, and Oncomine. A specific HMGB3-shRNA was used to knock down HMGB3 expression in order to investigate its effects on proliferation and cell cycle in vitro and in vivo.RESULTSElevated HMGB3 levels were first reported in hepatocarcinogenesis, with increasing expression from normal liver to cancer. Bioinformatic databases showed that HMGB3 expression in hepatocellular carcinoma tissues was significantly higher than that in normal liver tissues. Higher HMGB3 expression was discovered in liver cancer cells compared with LO2 cells in vitro. According to gene set enrichment analysis, HMGB3 mRNA levels were correlated with cell cycle and DNA replication pathways. Knocking down HMGB3 by specific shRNA significantly inhibited proliferation of HepG2 cells by cell cycle arrest and downregulating DNA replication related genes (cyclin B1, FEN1, and PCNA) at the mRNA and protein level. Furthermore, silencing HMGB3 significantly inhibited xenograft tumor growth (measured by Ki67) in vivo.CONCLUSIONHMGB3 is involved in malignant transformation of hepatocytes and could be a useful biomarker for diagnosis and a potential target for therapy of liver cancer.

Role of secretory clusterin in hepatocarcinogenesis.

Secretory clusterin (sCLU) is a small stress-induced cytoprotective chaperone protein. Its biological functions are similar to those of a heat-shock protein. The sCLU plays a crucial role in cell proliferation, multiple drug resistance, metastasis, and tumor progression. Abnormal sCLU expression in tumor tissues or sera of patients with primary hepatic cancer has been considered a useful biomarker for diagnosis and surveillance. However, the exact relationship between sCLU overexpression and malignant transformation of hepatocytes is still unknown. The present review examines some novel advances of the knowledge about the oncogenic role of sCLU in hepatocarcinogenesis.

Abstract 4496: Myofibroblast-secreted follistatin-like 1 promotes hepatocellular carcinoma formation and metastasis

Abstract Hepatocellular carcinoma (HCC) develops in the setting of fibrosis/cirrhosis, a progressive process in which chronic inflammation and hepatocellular regeneration result in the malignant transformation of hepatocytes. Enrichment of stromal myofibroblasts in this pathological stage is commonly observed, which constitutes the bulk of the tumor microenvironment and contributes to disease progression. Cancer cells are regulated by signals generated intrinsically and extrinsically from the tumor microenvironment. Targeting critical factors involved in this process may offer important therapeutic opportunities. Follistatin-like 1 (FSTL1) has been widely reported as a pro-inflammatory mediator in different fibrosis-related and inflammatory diseases. Here, we report that FSTL1 is either absent or expressed at very low levels in HCC cells, but preferentially secreted from the myofibroblasts of peri-tumor liver and HCC tissue as well as in the liver following acute injury. FSTL1 was found to co-localize and positively correlate with α-SMA, marker of myofibroblasts, in both human HCC as well as in a DEN+CCl4-induced HCC mouse model. High FSTL1 expression in myofibroblast FAP+ cells (FAP+/FSTL1high) also correlated with advanced TNM stages as compared to HCC patients in the FAP+/FSTL1low subgroup. Functional investigations revealed that FSTL1 can induce HCC cell proliferation, metastasis and sorafenib resistance; while FSTL1 attenuation by neutralizing antibody elicited the opposite effects. These observations were further validated in HCC patient-derived organoid cultures in which FSTL1 can enhance the metastatic effect of the cells. Transcriptome sequencing analysis is now currently underway to delineate the underlying molecular mechanism by which myofibroblast-secreted FSTL1 drives carcinogenesis and tumor progression in HCC. Citation Format: Natalie Tsz Wai Li, Man Tong, Lei Zhou, Wen Ning, Chung-Mau Lo, Kwan Man, Terence Kin-Wah Lee, Stephanie Kwai-Yee Ma. Myofibroblast-secreted follistatin-like 1 promotes hepatocellular carcinoma formation and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4496.

Abstract 2424: Hepatocellular carcinoma in the South Texas Latino population: Implications of STEAP2

Abstract Introduction: Hepatocellular carcinoma (HCC) is the most common type of liver cancer in adults and the third most common cause of cancer death worldwide; while incidence and mortality rates are two times higher in Latinos, incidence rates are the highest among Latinos in the South Texas region. The genetic and epigenetic events associated with the increased incidence of HCC in this population are largely unknown. We performed whole genome RNA sequencing in paired HCC tumor and adjacent non-tumor tissue total RNA from nine South Texas Latino patients. Analysis of differentially expressed genes revealed significant alterations in pathways associated with oxidative stress; most importantly, we found that the expression of STEAP2 (Six Transmembrane Epithelial Antigen of the Prostate 2) is increased five-fold in HCC tumor tissue compared to adjacent non-tumor tissue. In comparison to a non-Latino population, this finding was unique to South Texas Latinos. STEAP2 is a metalloreductase of iron and copper; reduced iron and copper ions can mediate the production of hydroxyl radicals resulting in increased oxidative stress, which can cause DNA damage and lipid peroxidation. We aim to prove that STEAP2 through regulation of iron and copper homeostasis, and an increase in oxidative stress, will lead to malignant transformation of hepatocytes resulting in tumor progression of HCC, including in obese hosts. Material and Methods: Latino paired HCC and adjacent non-tumor tissues were collected for RNA sequencing, metal ion measurement and oxidative stress markers. STEAP2 RNA and protein expression levels in Latino and Caucasian samples were evaluated by RT-PCR, Western blot, and immunohistochemistry. HCC cell lines (SNU398 and HUH7) with knockdown (KD) and overexpression (OE) of STEAP2 were created to examine the proliferation, migration, anchorage independent growth, and oxidative stress in vitro. Results: Analysis of RNA sequencing data demonstrated the overexpression of STEAP2 in HCC tumors in Latino patients, which were validated by RT-PCR and Western blot data. Lipid peroxidation product, 4-hydroxynonenal, and copper levels were higher in HCC tumor vs. adjacent tissue. KD of STEAP2 in the HCC cell lines decreased proliferation, migration and anchorage independent growth, while OE of STEAP2 increase migration and anchorage independent growth but not proliferation. Conclusions: STEAP2 is specifically overexpressed in HCC tumors in Latinos in comparison to HCC tumors in non-Latino whites and appears to play a malignant-promoting role in HCC cells. Further studies on the role of STEAP2 as a novel tumor promoter in HCC and the mechanisms by which it promotes carcinogenesis are underway. The proposed studies will likely yield mechanistic insights into the molecular mechanisms that drive HCC development and progression in South Texas Latinos and potential therapeutic targets. Citation Format: Carla Zeballos, Hakim Bouamar, Guixi Zheng, Xiang Gu, Yidong Chen, Francisco G. Cigarroa, Lu-Zhe Sun. Hepatocellular carcinoma in the South Texas Latino population: Implications of STEAP2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2424.

Key signal molecules of wingless-related integration pathway and targeted therapy for liver cancer

Hepatocellular carcinoma is one of the most common digestive system tumors. Its occurrence and development are considered as multi-factorial and multi-step process. Recent studies have shown that wingless-related integration (Wnt) pathway plays an important role in the HCC progression and is associated with malignant transformation of hepatocytes, HCC metastasis, drug resistance and liver cancer stem cells. This article analyzes the expression of key signaling molecules in Wnt pathway and its value in diagnosis, prognosis and targeted therapy, and outlines the research progress of Wnt pathway targeted drugs for the treatment of HCC, with a view to providing targeted therapy research for HCC reference.

Immunohistochemical and electron microscopic morphometric image analysis of hepatocellular carcinoma in association of HCV infection

ABSTRACTEarly detection of hepatocellular carcinoma (HCC) is crucial for successful therapy. The present work examined the value of ultrastructural morphometric image analysis of hepatocyte nuclei in patients with chronic hepatitis C virus (HCV) versus HCC cases with chronic HCV and the corresponding surgical tumor-free safe margins (TFMs), to highlight any early predictive signs of neoplastic cellular transformation. This work also performed an immunohistochemical assessment of cytokeratin 19 (CK19) and Ki-67-positive cells to visualize any associated proliferative activity in the examined groups.The results showed significant decrease in the hepatocyte nuclear surface areas in the HCC and TFMs versus those in the HCV cases. The hepatocyte nucleolar surface area was significantly increased in the HCC cases versus that in the HCV cases. This increase was associated with a significant increase in Ki-67-positive cells in the HCC cases compared to those in the other groups. Conversely, the mean number of CK 19-positive cells was significantly reduced in the HCC cases compared to the cell numbers in TFMs and HCV cases with severe hepatic fibrosis. Liver progenitor cells (LPCs) were discerned in the reactive ductules and canaliculo-ductular junctions that characterized TFMs. LPCs were sporadically distributed in the liver lobules and reactive bile ductules in the HCC samples.In conclusion, CK 19 represents an important marker for distinguishing between dysplastic and malignant liver nodules. Electron microscopic morphometric image analysis may be considered as adjunct factor for assessing hepatocyte malignant transformation. Wider scale studies are needed to authenticate these results.