Oncogenic driver genes and the inflammatory microenvironment dictate liver tumor phenotype

Aberrant differentiation and proliferation of hepatocytes in chronic liver injury and liver tumors

Chronic liver injury induces liver cirrhosis and facilitates hepatocarcinogenesis. However, the effects of this condition on hepatocyte proliferation and differentiation are unclear. We showed that rodent hepatocytes display a ductular phenotype when they are cultured within a collagenous matrix. This process involves transdifferentiation without the emergence of hepatoblastic features and is at least partially reversible. During the ductular reaction in chronic liver diseases with progressive fibrosis, some hepatocytes, especially those adjacent to ectopic ductules, demonstrate ductular transdifferentiation, but the majority of increased ductules originate from the existing bile ductular system that undergoes extensive remodeling. In chronic injury, hepatocyte proliferation is weak but sustained, and most regenerative nodules in liver cirrhosis are composed of clonally proliferating hepatocytes, suggesting that a small fraction of hepatocytes maintain their proliferative capacity in chronic injury. In mouse hepatocarcinogenesis models, hepatocytes activate the expression of various fetal/neonatal genes, indicating that these cells undergo dedifferentiation. Hepatocyte-specific somatic integration of various oncogenes in mice demonstrated that hepatocytes may be the cells of origin for a broad spectrum of liver tumors through transdifferentiation and dedifferentiation. In conclusion, the phenotypic plasticity and heterogeneity of mature hepatocytes are important for understanding the pathogenesis of chronic liver diseases and liver tumors.

Potential utility of l-carnitine for preventing liver tumors derived from metabolic dysfunction-associated steatohepatitis

BACKGROUND

Recent reports have unveiled the potential utility of l-carnitine to alleviate metabolic dysfunction-associated steatohepatitis (MASH) by enhancing mitochondrial metabolic function. However, its efficacy at preventing the development of HCC has not been assessed fully.

METHODS

l-carnitine (2 g/d) was administered to 11 patients with MASH for 10 weeks, and blood liver function tests were performed. Five patients received a serial liver biopsy, and liver histology and hepatic gene expression were evaluated using this tissue. An atherogenic plus high-fat diet MASH mouse model received long-term l-carnitine administration, and liver histology and liver tumor development were evaluated.

RESULTS

Ten-week l-carnitine administration significantly improved serum alanine transaminase and aspartate transaminase levels along with a histological improvement in the NAFLD activity score, while steatosis and fibrosis were not improved. Gene expression profiling revealed a significant improvement in the inflammation and profibrotic gene signature as well as the recovery of lipid metabolism. Long-term l-carnitine administration to atherogenic plus high-fat diet MASH mice substantially improved liver histology (inflammation, steatosis, and fibrosis) and significantly reduced the incidence of liver tumors. l-carnitine directly reduced the expression of the MASH-associated and stress-induced transcriptional factor early growth response 1. Early growth response 1 activated the promoter activity of neural precursor cell expressed, developmentally downregulated protein 9 (NEDD9), an oncogenic protein. Thus, l-carnitine reduced the activation of the NEDD9, focal adhesion kinase 1, and AKT oncogenic signaling pathway.

CONCLUSIONS

Short-term l-carnitine administration ameliorated MASH through its anti-inflammatory effects. Long-term l-carnitine administration potentially improved the steatosis and fibrosis of MASH and may eventually reduce the risk of HCC.

Possible protective anticancer effect of chloroform fraction of Iraqi Hibiscus tiliaceus L. leaves extract on diethylnitrosamine-induced hepatocarcinogenesis in male rats

OBJECTIVE

We aimed to examine the potential protective effects of Iraqi H. tiliaceus L. chloroform leaves extract on DEN-induced HCC in male Wistar Albino rats.

METHOD

Rats were assigned to four groups, six in each group. Group I: rats were administered a daily oral dose of 1 mL/kg/day of distilled water. Group II: rats were intraperitoneally injected with 70 mg/kg DEN once per week for 10 consecutive weeks. Group III: rats received 250 mg/kg of chloroform leaves extract. Groups IV: the rats were administered 500 mg/kg of chloroform leaves extract, along with their food, for five days per week over 20 weeks, with a subsequent dose of DEN once per week for 10 consecutive weeks.

RESULTS

The results indicate that the extract demonstrated a significant reduction (p<0.05) in oxidative stress, pro-inflammatory mediators, and HCC parameters, the extract also had a beneficial effect on liver function tests, and there was a significant elevation (p<0.05) of antioxidant parameters in a dose-dependent manner.

CONCLUSION

This study supports the protective properties of the chloroform extract of Iraqi H. tiliaceus L. leaves in HCC.

CXCL6: A potential therapeutic target for inflammation and cancer

Chemokines were originally defined as cytokines that affect the movement of immune cells. In recent years, due to the increasing importance of immune cells in the tumor microenvironment (TME), the role of chemokines has changed from a single "chemotactic agent" to a key factor that can regulate TME and affect the tumor phenotype. CXCL6, also known as granulocyte chemoattractant protein-2 (GCP-2), can recruit neutrophils to complete non-specific immunity in the process of inflammation. Cancer-related genes and interleukin family can promote the abnormal secretion of CXCL6, which promotes tumor growth, metastasis, epithelial mesenchymal transformation (EMT) and angiogenesis in the TME. CXCL6 also has a role in promoting fibrosis and tissue damage repair. In this review, we focus on the regulatory network affecting CXCL6 expression, its role in the progress of inflammation and how it affects tumorigenesis and progression based on the TME, in an attempt to provide a potential target for the treatment of diseases such as inflammation and cancer.

Prostate cancer cell-derived exosomal IL-8 fosters immune evasion by disturbing glucolipid metabolism of CD8+ T cell

Depletion of CD8+ T cells is a major obstacle in immunotherapy; however, the relevant mechanisms remain largely unknown. Here, we showed that prostate cancer (PCa) cell-derived exosomes hamper CD8+ T cell function by transporting interleukin-8 (IL-8). Compared to the low IL-8 levels detected in immune cells, PCa cells secreted the abundance of IL-8 and further accumulated in exosomes. The delivery of PCa cell-derived exosomes into CD8+ T cells exhausted the cells through enhanced starvation. Mechanistically, exosomal IL-8 overactivated PPARα in recipient cells, thereby decreasing glucose utilization by downregulating GLUT1 and HK2 but increasing fatty acid catabolism via upregulation of CPT1A and ACOX1. PPARα further activates uncoupling protein 1 (UCP1), leading to fatty acid catabolism for thermogenesis rather than ATP synthesis. Consequently, inhibition of PPARα and UCP1 restores CD8+ T cell proliferation by counteracting the effect of exosomal IL-8. This study revealed that the tumor exosome-activated IL-8-PPARα-UCP1 axis harms tumor-infiltrating CD8+ T cells by interfering with energy metabolism.

Metabolic reprogramming and its clinical implication for liver cancer

Cancer cells often encounter hypoxic and hypo-nutrient conditions, which force them to make adaptive changes to meet their high demands for energy and various biomaterials for biomass synthesis. As a result, enhanced catabolism (breakdown of macromolecules for energy production) and anabolism (macromolecule synthesis from bio-precursors) are induced in cancer. This phenomenon is called "metabolic reprogramming," a cancer hallmark contributing to cancer development, metastasis, and drug resistance. HCC and cholangiocarcinoma (CCA) are 2 different liver cancers with high intertumoral heterogeneity in terms of etiologies, mutational landscapes, transcriptomes, and histological representations. In agreement, metabolism in HCC or CCA is remarkably heterogeneous, although changes in the glycolytic pathways and an increase in the generation of lactate (the Warburg effect) have been frequently detected in those tumors. For example, HCC tumors with activated β-catenin are addicted to fatty acid catabolism, whereas HCC tumors derived from fatty liver avoid using fatty acids. In this review, we describe common metabolic alterations in HCC and CCA as well as metabolic features unique for their subsets. We discuss metabolism of NAFLD as well, because NAFLD will likely become a leading etiology of liver cancer in the coming years due to the obesity epidemic in the Western world. Furthermore, we outline the clinical implication of liver cancer metabolism and highlight the computation and systems biology approaches, such as genome-wide metabolic models, as a valuable tool allowing us to identify therapeutic targets and develop personalized treatments for liver cancer patients.

Melatonin Mitigates the Progression of Chemically Induced Hepatocellular Carcinoma in Rats via Targeting Wnt/Β-Catenin Pathway, and Small Noncoding miR-let-7b

Background

Melatonin, the controlling hormone of the sleep-wake cycle, has acquired attention due to its role in immunomodulation, anti-inflammation, as well as its proapoptotic effects. Wnt/β-catenin signaling can modulate cancer progression by promoting cell division and migration, while miR-let-7b may inhibit cell growth, migration, and invasion by affecting the function of adaptive immune cells. This work was designed to detect the effect of using melatonin as an immunomodulating therapeutic approach to control the progression of chemically induced hepatocellular carcinoma (HCC).

Methods

Thirty male rats were equally divided into control, HCC, and melatonin-HCC groups. Animals in the HCC and melatonin-HCC groups were injected with diethylnitrosamine (intraperitoneal single dose) followed by repeated carbon-tetrachloride subcutaneous injection once weekly for six weeks. Melatonin was given from the first week of the study and continued during the process of HCC induction.

Results

In the HCC group, the levels of tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF), and Wnt/β-catenin expression significantly increased, while there was a downregulation of microRNA Let7b. Melatonin administration reversed these changes, along with an increase in hepatic content of interleukin-2 (IL-2) and caspase-3.

Conclusions

Melatonin exerted hepatic immunomodulating changes, in addition to proapoptotic and antiangiogenic effects, illustrated by increased IL-2, caspase-3, and decreased VEGF levels, respectively. Moreover, the use of melatonin during hepatocarcinogenesis positively modulated the disrupted expression of microRNA let7b and Wnt/β-catenin significantly.

High blood galectin-3 level associated with risk of frailty in aging

Background

Frailty is one of the most problematic expressions of population aging, but its underlying mechanism has not been fully elucidated. Circulating galectin-3 (Gal-3) is involved in the pathogenesis of many age-related diseases. This study aims to explore the influence of circulating Gal-3 on the regulation of frailty and aging and to identify the potential mechanism further.

Methods

In this cross-sectional analysis, the Fried frailty phenotype (FP) was assessed among 149 community elderly residents in Shanghai. Peripheral blood mononuclear cells (PBMCs) were isolated by the Ficoll-Paque density gradient method, and differentially expressed genes (DEGs) encoding transcription factors in frailty were detected by Illumina and bioinformatics analyzed with R software. Gene Ontology (GO) enrichment analyses and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to explore the functional roles of these DEGs and the target genes related to frailty phenotypes. The serum Gal-3 concentration was tested by enzyme-linked immunosorbent assay (ELISA). Mouse frailty phenotype was used to construct an in vivo model of frailty, after which the serum levels of circulating Gal-3 and its gene expression levels in mouse tissues were determined.

Results

Participants' mean age was 72.04 ± 7.05 years. In total, 21.48% were frail and 36.91% were pre-frail. The mean serum Gal-3 concentration was 46.34 ± 17.99 ng/mL in frail participants, 32.30 ± 8.14 ng/mL in pre-frail participants, and 26.00 ± 5.87 ng/mL in non-frail individuals (p < 0.001). Significant positive correlations between serum Gal-3 level and FP score, SARC-F score, C-reactive protein (CRP), interleukin-6, etc., were observed. In addition, the KEGG pathway and GO enrichment analyses showed that 265 DEGs in PBMCs of frail participants were mainly related to inflammatory response, translation, RNA binding, protein binding, ribosome, and primary immunodeficiency. LGALS3 was identified as the overlapping gene between frailty-related DEGs and aging-related DEGs. The elevated serum Gal-3 concentration in the in vivo model of frailty was consistent with the results in participants.

Conclusion

In both community-dwelling older adults and aged mice, serum Gal-3 concentration was positively correlated with frailty. This circulating mediator may be a promising indicator of frailty.

Clinical trial registration

Chinese Clinical Trial Registry identifier, ChiCTR2000036399.

Circ-RAPGEF5 promotes intrahepatic cholangiocarcinoma progression by stabilizing SAE1 to facilitate SUMOylation

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy with a poor prognosis. The underlying functions and mechanisms of circular RNA and SUMOylation in the development of ICC remain poorly understood.

METHODS

Circular RNA hsa_circ_0001681 (termed Circ-RAPGEF5 hereafter) was identified by circular RNA sequencing from 19 pairs of ICC and adjacent tissue samples. The biological function of Circ-RAPGEF5 in tumor proliferation and metastasis was examined by a series of in vitro assays. A preclinical model was used to validate the therapeutic effect of targeting Circ-RAPGEF5. RNA pull-down and dual-luciferase reporter assays were used to access the RNA interactions. Western blot and Co-IP assays were used to detect SUMOylation levels.

RESULTS

Circ-RAPGEF5, which is generated from exons 2 to 6 of the host gene RAPGEF5, was upregulated in ICC. In vitro and in vivo assays showed that Circ-RAPGEF5 promoted ICC tumor proliferation and metastasis, and inhibited apoptosis. Additionally, high Circ-RAPGEF5 expression was significantly correlated with a poor prognosis. Further investigation showed that SAE1, a potential target of Circ-RAPGEF5, was also associated with poor oncological outcomes. RNA pull-down and dual-luciferase reporter assays showed an interaction of miR-3185 with Circ-RAPGEF5 and SAE1. Co-IP and western blot assays showed that Circ-RAPGEF5 is capable of regulating SUMOylation.

CONCLUSION

Circ-RAPGEF5 promotes ICC tumor progression and SUMOylation by acting as a sponge for miR-3185 to stabilize SAE1. Targeting Circ-RAPGEF5 or SAE1 might be a novel diagnostic and therapeutic strategy in ICC.

Unraveling the pathophysiologic role of galectin-3 in chronically injured liver

Galectin-3 (Gal-3) previously referred to as S-type lectins, is a soluble protein that specifically binds to β-galactoside carbohydrates with high specificity. Gal-3 plays a pivotal role in a variety of pathophysiological processes such as cell proliferation, inflammation, differentiation, angiogenesis, transformation and apoptosis, pre-mRNA splicing, metabolic syndromes, fibrosis, and host defense. The role of Gal-3 has also been implicated in liver diseases. Gal-3 is activated upon a hepatotoxic insult to the liver and its level has been shown to be upregulated in fatty liver diseases, inflammation, nonalcoholic steatohepatitis, fibrosis, cholangitis, cirrhosis, and hepatocellular carcinoma (HCC). Gal-3 directly interacts with the NOD-like receptor family, pyrin domain containing 3, and activates the inflammasome in macrophages of the liver. In the chronically injured liver, Gal-3 secreted by injured hepatocytes and immune cells, activates hepatic stellate cells (HSCs) in a paracrine fashion to acquire a myofibroblast like collagen-producing phenotype. Activated HSCs in the fibrotic liver secrete Gal-3 which acts via autocrine signaling to exacerbate extracellular matrix synthesis and fibrogenesis. In the stromal microenvironment, Gal-3 activates cancer cell proliferation, migration, invasiveness, and metastasis. Clinically, increased serum levels and Gal-3 expression were observed in the liver tissue of nonalcoholic steatohepatitis, fibrotic/cirrhotic, and HCC patients. The pathological role of Gal-3 has been experimentally and clinically reported in the progression of chronic liver disease. Therefore, this review discusses the pathological role of Gal-3 in the progression of chronic liver diseases.

Gradual deterioration of fatty liver disease to liver cancer via inhibition of AMPK signaling pathways involved in energy-dependent disorders, cellular aging, and chronic inflammation

Introduction

Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer kind. According to recent research, a fatty liver increases the risk of hepatocellular cancer. Nevertheless, the AMPK signaling pathway is crucial. In addition, 5'-AMP-activated protein kinase (AMPK) is strongly linked to alterations in the tumor microenvironment, such as inflammation, hypoxia, and aging. The objective of this study is to evaluate the impact of the AMPK signaling pathway on the progression of fatty liver to HCC.

Methods

In this study, we established a mouse liver cancer model using high-fat diets and nano-nitrosamines (nano-DEN). In addition, we employed a transcriptomic technique to identify all mRNAs detected in liver samples at the 25th weekexpression of proteins linked with the LKB1-AMPK-mTOR signaling pathway, inflammation, aging, and hypoxia was studied in microarrays of liver cancer tissues from mice and humans. These proteins included p-AMPK, LKB1, mTOR, COX-2, β-catenin, HMGB1, p16, and HIF-1α.

Results

Data were collected at different times in the liver as well as in cancerous and paracancerous regions and analyzed by a multispectral imaging system. The results showed that most of the genes in the AMPK signaling pathway were downregulated. Prakk1 expression was upregulated compared to control group but downregulated in the cancerous regions compared to the paracancerous regions. Stk11 expression was downregulated in the cancerous regions. Mtor expression was upregulated in the cancerous regions. During liver cancer formation, deletion of LKB1 in the LKB1-AMPK-mTOR signaling pathway reduces phosphorylation of AMPK. It contributed to the upregulation of mTOR, which further led to the upregulation of HIF1α. In addition, the expression of β-catenin, COX-2, and HMGB1 were upregulated, as well as the expression of p16 was downregulated.

Discussion

These findings suggest that changes in the AMPK signaling pathway exacerbate the deterioration of disrupted energy metabolism, chronic inflammation, hypoxia, and cellular aging in the tumor microenvironment, promoting the development of fatty liver into liver cancer.

miR-579-3p Controls Hepatocellular Carcinoma Formation by Regulating the Phosphoinositide 3-Kinase-Protein Kinase B Pathway in Chronically Inflamed Liver

Chronic liver inflammation causes continuous liver damage with progressive liver fibrosis and cirrhosis, which may eventually lead to hepatocellular carcinoma (HCC). Whereas the 10-year incidence for HCC in patients with cirrhosis is approximately 20%, many of these patients remain tumor free for their entire lives. Clarifying the mechanisms that define the various outcomes of chronic liver inflammation is a key aspect in HCC research. In addition to a wide variety of contributing factors, microRNAs (miRNAs) have also been shown to be engaged in promoting liver cancer. Therefore, we wanted to characterize miRNAs that are involved in the development of HCC, and we designed a longitudinal study with formalin-fixed and paraffin-embedded liver biopsy samples from several pathology institutes from Switzerland. We examined the miRNA expression by nCounterNanostring technology in matched nontumoral liver tissue from patients developing HCC (n = 23) before and after HCC formation in the same patient. Patients with cirrhosis (n = 26) remaining tumor free within a similar time frame served as a control cohort. Comparison of the two cohorts revealed that liver tissue from patients developing HCC displayed a down-regulation of miR-579-3p as an early step in HCC development, which was further confirmed in a validation cohort. Correlation with messenger RNA expression profiles further revealed that miR-579-3p directly attenuated phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) expression and consequently protein kinase B (AKT) and phosphorylated AKT. In vitro experiments and the use of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology confirmed that miR-579-3p controlled cell proliferation and cell migration of liver cancer cell lines. Conclusion: Liver tissues from patients developing HCC revealed changes in miRNA expression. miR-579-3p was identified as a novel tumor suppressor regulating phosphoinositide 3-kinase-AKT signaling at the early stages of HCC development.

C-Reactive Protein Is an Indicator of the Immunosuppressive Microenvironment Fostered by Myeloid Cells in Hepatocellular Carcinoma

BACKGROUND

C-reactive protein (CRP) is a widely used marker of systemic inflammation and predicts poor clinical outcomes in patients with hepatocellular carcinoma (HCC); however, its significance in the local immune response at the tumor site is not clear.

METHODS

Serum CRP levels of 329 HCC patients were detected before resection. Paired paraffin-embedded tumor samples were used to quantify immune cell populations, such as CD11b+ myeloid cells, CD68+ macrophages (Mφs), CD15+ neutrophils, CD8+ T cells, and CD206+, CD204+, CD163+ and CD169+ Mφs, by immunohistochemistry. Enrichment scores for 34 types of immune cells based on transcriptome data from 24 HCC samples were calculated by xCell. Overall survival of patients was analyzed using the Kaplan-Meier method.

RESULTS

Serum CRP levels were correlated with liver functions and tumor stages in patients with HCC. The densities of CD68+ tumor-associated macrophages (TAMs) and CD15+ tumor-associated neutrophils (TANs) were significantly higher in patients with elevated serum CRP levels than in those with low CRP levels (both p < 0.0001). Further analysis of TAM subtypes revealed that serum CRP levels were associated with CD204+ and CD163+ Mφ densities (p < 0.0001 and p = 0.0003, respectively). Moreover, transcriptome data showed that CRP expression was associated with the expression of myeloid cell infiltration-related genes in HCC tumors. The combination of serum CRP with TAMs or TANs in both the nontumor and intratumor regions could represent a powerful criterion for predicting patient prognoses.

CONCLUSION

Serum CRP could serve as an indicator of an immunosuppressive TME in HCC, which could be of potential clinical application for treatment strategies targeting the TME.

DEN-Induced Rat Model Reproduces Key Features of Human Hepatocellular Carcinoma

Simple Summary

Hepatocellular carcinoma is the most frequent form of primary liver cancer, characterized by increasing incidence and high mortality. Animal models of hepatocellular carcinoma are widely used to study the biology of cancer and to test potential therapies. Herein, we describe how the rat model of DEN-induced hepatocellular carcinoma mimics the pathogenesis of hepatocellular carcinoma seen in humans, including liver damage, chronic inflammation, hepatocytes proliferation, liver fibrosis and cirrhosis, disorganized vasculature, and modulations of the liver’s immune microenvironment. Our results should help the hepatocellular carcinoma field to better tailor the use of the DEN-induced rat liver cancer model for testing specific experimental hypotheses or to perform preclinical testing.

Abstract

Hepatocellular carcinoma (HCC) is the most common type of liver cancer. The majority of HCC cases are associated with liver fibrosis or cirrhosis developing from chronic liver injuries. The immune system of the liver contributes to the severity of tissue damage, the establishment of fibrosis and the disease’s progression towards HCC. Herein, we provide a detailed characterization of the DEN-induced HCC rat model during fibrosis progression and HCC development with a special focus on the liver’s inflammatory microenvironment. Fischer 344 male rats were treated weekly for 14 weeks with intra-peritoneal injections of 50 mg/kg DEN. The rats were sacrificed before starting DEN-injections at 0 weeks, after 8 weeks, 14 weeks and 20 weeks after the start of DEN-injections. We performed histopathological, immunohistochemical, RT-qPCR, RNA-seq and flow cytometry analysis. Data were compared between tumor and non-tumor samples from the DEN-treated versus untreated rats, as well as versus human HCCs. Chronic DEN injections lead to liver damage, hepatocytes proliferation, liver fibrosis and cirrhosis, disorganized vasculature, and a modulated immune microenvironment that mimics the usual events observed during human HCC development. The RNA-seq results showed that DEN-induced liver tumors in the rat model shared remarkable molecular characteristics with human HCC, especially with HCC associated with high proliferation. In conclusion, our study provides detailed insight into hepatocarcinogenesis in a commonly used model of HCC, facilitating the future use of this model for preclinical testing.

Comprehensive analysis of the cancer driver genes in breast cancer demonstrates their roles in cancer prognosis and tumor microenvironment

Background

Breast cancer is the most common malignancy in women. Cancer driver gene-mediated alterations in the tumor microenvironment are critical factors affecting the biological behavior of breast cancer. The purpose of this study was to identify the expression characteristics and prognostic value of cancer driver genes in breast cancer.

Methods

The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets are used as the training and test sets. Classified according to cancer and paracancerous tissues, we identified differentially expressed cancer driver genes. We further screened prognosis-associated genes, and candidate genes were submitted for the construction of a risk signature. Functional enrichment analysis and transcriptional regulatory networks were performed to search for possible mechanisms by which cancer driver genes affect breast cancer prognosis.

Results

We identified more than 200 differentially expressed driver genes and 27 prognosis-related genes. High-risk group patients had a lower survival rate compared to the low-risk group (P<0.05), and risk signature showed high specificity and sensitivity in predicting the patient prognosis (AUC 0.790). Multivariate regression analysis suggested that risk scores can independently predict patient prognosis. Further, we found differences in PD-1 expression, immune score, and stromal score among different risk groups.

Conclusion

Our study confirms the critical prognosis role of cancer driver genes in breast cancer. The cancer driver gene risk signature may provide a novel biomarker for clinical treatment strategy and survival prediction of breast cancer.

The deficiency of FKBP-5 inhibited hepatocellular progression by increasing the infiltration of distinct immune cells and inhibiting obesity-associated gut microbial metabolite

Background

Gut microbiota has a number of essential roles in nutrition metabolism and immune homeostasis, and is closely related to hepatocellular progression. In recent years, studies have also shown that FK506 binding protein 5 (FKBP-5) plays a crucial role in immune regulation. However, it is not yet clear whether FKBP-5 promotes the development of hepatocellular carcinoma (HCC) by affecting immune function and gut microbiota.

Methods

FKBP-5 expression was verified by immunochemistry and western blot and reverse transcription polymerase chain reaction (RT-qPCR) assays. After treatment in WT and FKBP-5^-/- mice, the histological characteristic of mice liver tissue was assessed by H&E staining, and hepatic leukocytes and hepatic NKT cells were identified by flow cytometer. Meanwhile, primary bile acids (BAs), secondary BAs, serum total cholesterol, and the weight of abdomen adipose tissues were examined, and the gut microbiota was evaluated by 16S ribosomal ribonucleic acid (rRNA) sequencing.

Results

We discovered that FKBP-5 was highly expressed in HCC tissues. Meanwhile, FKBP-5 deletion inhibited tumor progression by increasing CD⁸⁺ T, CD⁴⁺ T, NKT and CD⁴⁺NKT cells in mice after diethylnitrosamine (DEN) injection. Besides, we proved that FKBP-5 deletion generated rapid and significant reductions in the intestinal BAs, the weight of abdomen adipose tissues and the serum total cholesterol. FKBP-5 deletion also led to a change in the composition of gut microbiota, suggesting that BAs are the main dietary factor regulating gut microbiota, which could be affected by FKBP-5 deletion. Further, we uncovered that anti-CD4 and anti-CD8 treatments facilitated hepatocellular progression by modulating gut microbiota composition in FKBP-5^-/- mice.

Conclusions

Therefore, we demonstrated that FKBP-5 deletion inhibited hepatocellular progression by modulating immune response and gut microbiome-mediated BAs metabolism.

SPTBN1 inhibits inflammatory responses and hepatocarcinogenesis via the stabilization of SOCS1 and downregulation of p65 in hepatocellular carcinoma

Background: Spectrin, beta, non-erythrocytic 1 (SPTBN1), an adapter protein for transforming growth factor beta (TGF-β) signaling, is recognized as a tumor suppressor in the development of hepatocellular carcinoma (HCC); however, the underlying molecular mechanisms of this tumor suppression remain obscure.

Methods: The effects on expression of pro-inflammatory cytokines upon the inhibition or impairment of SPTBN1 in HCC cell lines and liver tissues of Sptbn1^+/- and wild-type (WT) mice were assessed by analyses of quantitative real-time reverse-transcription polymerase chain reaction (QRT-PCR), enzyme linked immunosorbent assay (ELISA), Western blotting and gene array databases from HCC patients. We investigated the detailed molecular mechanisms underlying the inflammatory responses by immunoprecipitation-Western blotting, luciferase reporter assay, chromatin immunoprecipitation quantitative real time PCR (ChIP-qPCR), immunohistochemistry (IHC) and electrophoretic mobility shift assay (EMSA). The proportion of myeloid-derived suppressor cells in liver, spleen, bone marrow and peripheral blood samples from WT and Sptbn1^+/- mice were measured by fluorescence-activated cell sorting (FACS) analysis. Further, the hepatocacinogenesis and its correlation with inflammatory microenvironment by loss of SPTBN1/SOCS1 and induction of p65 were analyzed by treating WT and Sptbn1^+/- mice with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC).

Results: Loss of SPTBN1 in HCC cells upregulated the expression of pro-inflammatory cytokines including interleukin-1α (IL-1α), IL-1β, and IL-6, and enhanced NF-κB transcriptional activation. Mechanistic analyses revealed that knockdown of SPTBN1 by siRNA downregulated the expression of suppressor of cytokine signaling 1 (SOCS1), an E3 ligase of p65, and subsequently upregulated p65 accumulation in the nucleus of HCC cells. Restoration of SOCS1 abrogated this SPTBN1 loss-associated elevation of p65 in HCC cells. In human HCC tissues, SPTBN1 gene expression was inversely correlated with gene expression of IL-1α, IL-1β and IL-6. Furthermore, a decrease in the levels of SPTBN1 gene, as well as an increase in the gene expression of IL-1β or IL-6 predicted shorter relapse free survival in HCC patients, and that HCC patients with low expression of SPTBN1 or SOCS1 protein is associated with poor survival. Heterozygous loss of SPTBN1 (Sptbn1^+/-) in mice markedly upregulated hepatic expression of IL-1α, IL-1β and IL-6, and elevated the proportion of myeloid-derived suppressor cells (MDSCs) and CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Foxp3⁺Treg) cells in the liver, promoting hepatocarcinogenesis of mouse fed by DDC.

Conclusions: Our findings provided evidence that loss of SPTBN1 in HCC cells increases p65 protein stability via the inhibition of SOCS1 and enhances NF-κB activation, stimulating the release of inflammatory cytokines, which are critical molecular mechanisms for the loss of SPTBN1-induced liver cancer formation. Reduced SPTBN1 and SOCS1 predict poor outcome in HCC patients.

Oncogenic driver genes and tumor microenvironment determine the type of liver cancer

Primary liver cancer (PLC) may be mainly classified as the following four types: hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), hepatoblastoma (HB), and combined hepatocellular carcinoma and intrahepatic cholangiocarcinoma (cHCC-ICC). The majority of PLC develops in the background of tumor microenvironment, such as inflammatory microenvironments caused by viral hepatitis, alcoholic or nonalcoholic steatohepatitis, carbon tetrachloride (CCl₄), 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC), and necroptosis-associated hepatic cytokine microenvironment caused by necroptosis of hepatocytes. However, the impact of different types of microenvironments on the phenotypes of PLC generated by distinct oncogenes is still unclear. In addition, the cell origin of different liver cancers have not been clarified, as far as we know. Recent researches show that mature hepatocytes retain phenotypic plasticity to differentiate into cholangiocytes. More importantly, our results initially demonstrated that HCC, ICC, and cHCC-ICC could originate from mature hepatocytes rather than liver progenitor cells (LPCs), hepatic stellate cells (HSCs) and cholangiocytes in AKT-driven, AKT/NICD-driven and AKT/CAT-driven mouse PLC models respectively by using hydrodynamic transfection methodology. Therefore, liver tumors originated from mature hepatocytes embody a wide spectrum of phenotypes from HCC to CC, possibly including cHCC-ICC and HB. However, the underlying mechanism determining the cancer phenotype of liver tumors has yet to be delineated. In this review, we will provide a summary of the possible mechanisms for directing the cancer phenotype of liver tumors (i.e., ICC, HCC, and cHCC-ICC) in terms of oncogenic driver genes and tumor microenvironment. Moreover, this study initially revealed the cell origin of different types of liver cancer.

Mouse Models of Oncoimmunology in Hepatocellular Carcinoma

Liver cancer is the fourth leading cause of cancer-related mortality worldwide and incidence is on the rise. Hepatocellular carcinoma (HCC) is the most common form of liver cancer, with a complex etiology and limited treatment options. The standard-of-care treatment for patients with advanced HCC is sorafenib, a tyrosine kinase inhibitor that offers limited survival benefit. In the past years, therapeutic options for the treatment of advanced HCC have increased substantially, including additional multikinase inhibitors as well as immune checkpoint inhibitors. Nivolumab and pembrolizumab were approved in 2017 and 2018, respectively, as second-line treatment in advanced HCC. These drugs, both targeting the programmed death-1 pathway, demonstrate unprecedented results, with objective response rates of approximately 20%. However, the majority of patients do not respond, necessitating the identification of biomarkers of response and resistance to immunotherapy. With the recent success of immunotherapies in oncology, mouse models that better recapitulate the human disease and antitumor immune response are needed. This review lists ongoing clinical trials testing immunotherapy in HCC, briefly discusses the unique immunosuppressive environment of the liver, and then delves into the most applicable current murine model systems to study oncoimmunology within the context of HCC, including syngeneic, genetically engineered, and humanized models.

Liver Fibrosis: Mechanistic Concepts and Therapeutic Perspectives

Liver fibrosis due to viral or metabolic chronic liver diseases is a major challenge of global health. Correlating with liver disease progression, fibrosis is a key factor for liver disease outcome and risk of hepatocellular carcinoma (HCC). Despite different mechanism of primary liver injury and disease-specific cell responses, the progression of fibrotic liver disease follows shared patterns across the main liver disease etiologies. Scientific discoveries within the last decade have transformed the understanding of the mechanisms of liver fibrosis. Removal or elimination of the causative agent such as control or cure of viral infection has shown that liver fibrosis is reversible. However, reversal often occurs too slowly or too infrequent to avoid life-threatening complications particularly in advanced fibrosis. Thus, there is a huge unmet medical need for anti-fibrotic therapies to prevent liver disease progression and HCC development. However, while many anti-fibrotic candidate agents have shown robust effects in experimental animal models, their anti-fibrotic effects in clinical trials have been limited or absent. Thus, no approved therapy exists for liver fibrosis. In this review we summarize cellular drivers and molecular mechanisms of fibrogenesis in chronic liver diseases and discuss their impact for the development of urgently needed anti-fibrotic therapies.

Murine hepatoblast-derived liver tumors resembling human combined hepatocellular-cholangiocarcinoma with stem cell features

BACKGROUND

Combined hepatocellular-cholangiocarcinoma (CHC) is a primary hepatic malignancy with heterogeneously combined histological features of putative hepatic progenitor cells (HPC) origin. We describe a mouse model that exhibits the heterogenous histological and phenotypic finding similar to human CHC.

METHODS

We injected hepatoblasts isolated from p53-/- C57BL/6 mice into syngeneic wild-type pre-conditioned C57BL/6 mice. We confirmed that p53-/- murine hepatoblasts act as tumor-initiating cells (TICs) that generate CHC both in situ and within metastases. For comparative pathological study, 8 human cases of CHC with stem cell features were recruited by immunohistochemistry and multicolor fluorescence immunostaining.

RESULTS

We identified corresponding areas in murine tumors matching each WHO criteria-described subtype of human CHC. In both murine and human tumors, HPC-like cells in tumor nests and associated stem cell features/traits are suggested histologically to be the progenitor origin of the cancer.

CONCLUSIONS

The pathological characteristics of murine tumors recapitulate human CHC with stem cell features. These data provide additional comparative pathological evidence that CHC with stem cell features originate from HPCs and validate a model to study this cancer type in vivo.

Genetically engineered animal models of biliary tract cancers

PURPOSE OF REVIEW

Biliary tract cancers which include intrahepatic and extrahepatic cholangiocarcinomas and gallbladder cancer, are characterized by poor outcome. Therefore, identifying the molecular mechanisms of the disease has become a priority. However, such identification has to cope with extreme heterogeneity of the disease, which results from the variable anatomical location, the numerous cell types of origin and the high number of known genetic alterations.

RECENT FINDINGS

Animal models can develop invasive and metastatic tumours that recapitulate as faithfully as possible the molecular features of the human tumours. To generate animal models of cholangiocarcinoma, investigators resorted to the administration of carcinogens, induction of cholestasis, grafting of tumour cells and induction of genetic modifications.

SUMMARY

Here, we summarize the currently available genetically engineered animal models, and focus on mice and zebrafish. The experimental strategies that were selected to induce cholangiocarcinoma in a time-controlled and cell-type-specific manner are critically examined. We discuss their strengths and limitations while considering their relevance to human pathophysiology.

Identification of a Pan-Gamma-Secretase Inhibitor Response Signature for Notch-Driven Cholangiocarcinoma

Cholangiocarcinoma (CCA) mortality rates are increasing as a result of rising incidence and limited curative treatment(s) for patients with advanced disease. NOTCH pathway reactivation has been reported in biliary malignancies to conflicting degrees, hindering prioritization of key therapeutic targets within the network and identification of candidate responder patients for NOTCH-directed therapies. We analyzed genomic data from 341 patients with CCA and identified NOTCH1 significantly increased in a subgroup characterized by distinct stromal infiltration. Network-wide imbalance of the NOTCH pathway was seen in CCA, including correlation of NOTCH1 with NOTCH3 and NOTCH ligands. Given the diversity of observed NOTCH receptor engagement, γ-secretase modulation was rationalized as a therapeutic option. Indeed, subcutaneous transplantation of sensitive and resistant CCA cell lines pretreated with a γ-secretase inhibitor (GSi) cocktail demonstrated the antineoplastic effects of GSi in a subset of CCA and led to the development of a 225-gene responder signature. This signature was validated in an independent cohort of 119 patients. Further, this signature was enriched in liver tumors initiated by hydrodynamic injections of activated-NOTCH as compared with the AKT-RAS-driven tumors. Candidate GSi-responder patients were characterized by distinct transcriptomes overlapping with previous hepatobiliary metastasis and stemness, unique stromal properties, and dysfunctional intratumoral immune infiltration. Pan-cancer analysis identified 41.9% of cancer types to harbor prospective GSi-responder patients, which was adapted into a 20-gene GSi-sensitivity score metric capable of discriminating nanomolar versus micromolar sensitivity to a cell-permeable GSi (Z-LLNle-CHO) across 60 diverse tumor lines (area under the curve = 1). Conclusion: We have established a GSi-responder signature with evidence across several patient cohorts, as well as in vitro and in vivo models, to enable precision medicine application of NOTCH-directed therapy in CCA as well as prospectively across diverse malignancies.

Shikonin induces colorectal carcinoma cells apoptosis and autophagy by targeting galectin-1/JNK signaling axis

Colorectal carcinoma (CRC) is the third most common malignant tumor pathology worldwide. Despite progress in surgical procedures and therapy options, CRC is still a considerable cause of cancer-related mortality. In this study, we tested the antitumor effects of shikonin in CRC and tried to identify its potential mechanism. The potential target, molecular mechanism as well as in vitro and in vivo antitumor effects of shikonin in CRC cells were determined by an integrative protocol including quantitative proteomics, RT-PCR, western blotting, RNA interference and overexpression, apoptosis and autophagy assays, etc. Galectin-1 was a potential target of shikonin from the iTRAQ-based proteomic analysis in shikonin-treated SW620 cell. The overexpression and RNA silencing of galectin-1 in two CRC cells suggested that the shikonin sensitivity was correlation to galectin-1 levels. The ROS accumulation induced by shikonin was important to the formation of galectin-1 dimers. Dimer galectin-1 was found to be associated with the activation of JNK and downstream apoptosis or autophagy. Moreover, through functional in vitro studies, we showed that differences in galectin-1 level affected tumor cell proliferation, migration, and invasion. In summary, shikonin induced CRC cells apoptosis and autophagy by targeting galectin-1 and JNK signaling pathway both in vitro and in vivo, which suggested a potential novel therapy target for CRC.

Context-Dependent Role of NF-κB Signaling in Primary Liver Cancer-from Tumor Development to Therapeutic Implications

Chronic inflammatory cell death is a major risk factor for the development of diverse cancers including liver cancer. Herein, disruption of the hepatic microenvironment as well as the immune cell composition are major determinants of malignant transformation and progression in hepatocellular carcinomas (HCC). Considerable research efforts have focused on the identification of predisposing factors that promote induction of an oncogenic field effect within the inflammatory liver microenvironment. Among the most prominent factors involved in this so-called inflammation-fibrosis-cancer axis is the NF-κB pathway. The dominant role of this pathway for malignant transformation and progression in HCC is well documented. Pathway activation is significantly linked to poor prognostic traits as well as stemness characteristics, which places modulation of NF-κB signaling in the focus of therapeutic interventions. However, it is well recognized that the mechanistic importance of the pathway for HCC is highly context and cell type dependent. While constitutive pathway activation in an inflammatory etiological background can significantly promote HCC development and progression, absence of NF-κB signaling in differentiated liver cells also significantly enhances liver cancer development. Thus, therapeutic targeting of NF-κB as well as associated family members may not only exert beneficial effects but also negatively impact viability of healthy hepatocytes and/or cholangiocytes, respectively. The review presented here aims to decipher the complexity and paradoxical functions of NF-κB signaling in primary liver and non-parenchymal cells, as well as the induced molecular alterations that drive HCC development and progression with a particular focus on (immune-) therapeutic interventions.

Block of NF-kB signaling accelerates MYC-driven hepatocellular carcinogenesis and modifies the tumor phenotype towards combined hepatocellular cholangiocarcinoma

Primary liver cancer ranks among the leading causes of cancer death worldwide. Risk factors are closely linked to inflammation, such as viral hepatitis and alcoholic as well as non-alcoholic steatohepatitis. Among the pathways involved in the pathogenesis of malignant liver tumors, dysregulation of NF-κB signaling plays a prominent role. It provides a link between inflammation and cancer. To examine the role of NF-κB in a MYC-induced model of hepatocellular carcinoma we deleted NEMO (IKKγ) specifically from hepatocytes. NEMO deletion accelerated tumor development and shortened survival, suggesting a tumor-suppressive function of NF-κB signaling. We observed increased proliferation, inflammation and fibrosis, as well as activation of MAPK and STAT signaling. Importantly, deletion of NEMO modified the tumor phenotype from hepatocellular carcinoma to combined hepatocellular cholangiocarcinoma. The intrahepatic cholangiocarcinoma tumor component showed increased expression of progenitor markers such as Sox9 and reduced expression of mature hepatic markers such as CPS1. In both cases tumorigenesis was reversible by turning off MYC expression. To our knowledge this is the first mouse model of combined hepatocellular cholangiocarcinoma and may provide insights into the development of this rare malignant tumor.

Aberrantly DNA Methylated-Differentially Expressed Genes and Pathways in Hepatocellular Carcinoma

Background: Methylation plays a significant role in the etiology and pathogenesis of hepatocellular carcinoma (HCC). The aim of the present study is to identify aberrantly methylated-diferentially expressed genes (DEGs) and dysregulated pathways associated with the development of HCC through integrated analysis of gene expression and methylation microarray.

Method: Aberrantly methylated-DEGs were identified from gene expression microarrays (GSE62232, GSE74656) and gene methylation microarrays (GSE44909, GSE57958). Functional enrichment and pathway enrichment analyses were performed through the database of DAVID. Protein-protein interaction (PPI) network was established by STRING and visualized in Cytoscape. Subsequently, overall survival (OS) analysis of hub genes was performed by OncoLnc. Finally, we validated the expression level of CDCA5 by quantitative real-time PCR (qRT-PCR) and western blotting, and performed Immunohistochemical experiments utilizing a tissue microarray. Cell growth assay and flow cytometry were behaved to explore the function of CDCA5.

Results: Aberrantly methylated-DEGs were enriched in biological process, molecular function, cellular component and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Among them, cell cycle was enriched most frequently, and some terms associated with cancer were enriched, such as p53 signaling pathway, pathways in cancers, PI3K-Akt signaling pathway and AMPK signaling pathway. After survival analysis and validation in TCGA database including methylation and gene expression status, 12 hub genes were identified. Furthermore, the expression level of new gene CDCA5 was validated in HCC cell lines and hepatic normal cell lines through qRT-PCR and western blotting. In additional, immunohistochemistry experiments revealed higher CDCA5 protein expression from HCC tumor tissues compared with paracancer tissues by tissue microarray. Finally, through loss of function, we demonstrated that CDCA5 promoted proliferation by regulating the cell cycle.

Conclusions: In summary, the present study implied possible aberrantly methylated-differentially expressed genes and dysregulated pathways in HCC by bioinformatics analysis and experiments, which could be helpful in understanding the molecular mechanisms underlying the development and progression of HCC. Hub genes including CDC20, AURKB, BIRC5, RRM2, MCM2, PTTG1, CDKN2A, NEK2, CENPF, RACGAP1, GNA14 and especially the new gene CDCA5 may serve as biomarkers for diagnosis, treatment and prognosis of HCC.

Ginkgo biloba induces different gene expression signatures and oncogenic pathways in malignant and non-malignant cells of the liver

Ginkgo biloba (EGb761) is a widely used botanical drug. Several reports indicate that EGb761 confers preventive as well as anti-tumorigenic properties in a variety of tumors, including hepatocellular carcinoma (HCC). We here evaluate functional effects and molecular alterations induced by EGb761 in hepatoma cells and non-malignant hepatocytes. Hepatoma cell lines, primary human HCC cells and immortalized human hepatocytes (IH) were exposed to various concentrations (0–1000 μg/ml) of EGb761. Apoptosis and proliferation were evaluated after 72h of EGb761 exposure. Response to oxidative stress, tumorigenic properties and molecular changes were further investigated. While anti-oxidant effects were detected in all cell lines, EGb761 promoted anti-proliferative and pro-apoptotic effects mainly in hepatoma cells. Consistently, EGb761 treatment caused a significant reduction in colony and sphere forming ability in hepatoma cells and no mentionable changes in IH. Transcriptomic changes involved oxidative stress response as well as key oncogenic pathways resembling Nrf2- and mTOR signaling pathway. Taken together, EGb761 induces differential effects in non-transformed and cancer cells. While treatment confers protective effects in non-malignant cells, EGb761 significantly impairs tumorigenic properties in cancer cells by affecting key oncogenic pathways. Results provide the rational for clinical testing of EGb761 in preventive and therapeutic strategies in human liver diseases.

A Novel 3D in Vitro Tumor Model Based on Silk Fibroin/Chitosan Scaffolds To Mimic the Tumor Microenvironment

Drug development involves various evaluation processes to ascertain drug effects and rigorous analysis of biological indicators during in vitro preclinical studies. Two-dimensional (2D) cell cultures are commonly used in numerous in vitro studies, which are poor facsimiles of the in vivo conditions. Recently, three-dimensional (3D) tumor models mimicking the tumor microenvironment and reducing the use of experimental animals have been developed generating great interest to appraise tumor response to treatment strategies in cancer therapy. In this study, silk fibroin (SF) protein and chitosan (CS), two natural biomaterials, were chosen to construct the scaffolds of 3D cell models. Human non-small cell lung cancer A549 cells in the SF/CS scaffolds were found to have a great tendency to gather and form tumor spheres. A549 cell spheres in the 3D scaffolds showed biological and morphological characteristics much closer to the in vivo tumors. Besides, the cells in 3D models displayed better invasion ability and drug resistance than 2D models. Additionally, differences in drug-resistant and immune-related protein levels were found, which indicated that 3D models might resemble the real-life situation. These findings suggested that these 3D tumor models composed of SF/CS are promising to provide a valuable biomaterial platform in the evaluation of anticancer drugs.

A Herpes Simplex Virus Thymidine Kinase-Induced Mouse Model of Hepatocellular Carcinoma Associated with Up-Regulated Immune-Inflammatory-Related Signals

Inflammation and fibrosis in human liver are often precursors to hepatocellular carcinoma (HCC), yet none of them is easily modeled in animals. We previously generated transgenic mice with hepatocyte-specific expressed herpes simplex virus thymidine kinase (HSV-tk). These mice would develop hepatitis with the administration of ganciclovir (GCV)(Zhang, 2005 #1). However, our HSV-tk transgenic mice developed hepatitis and HCC tumor as early as six months of age even without GCV administration. We analyzed the transcriptome of the HSV-tk HCC tumor and hepatitis tissue using microarray analysis to investigate the possible causes of HCC. Gene Ontology (GO) enrichment analysis showed that the up-regulated genes in the HCC tissue mainly include the immune-inflammatory and cell cycle genes. The down-regulated genes in HCC tumors are mainly concentrated in the regions related to lipid metabolism. Gene set enrichment analysis (GSEA) showed that immune-inflammatory-related signals in the HSV-tk mice are up-regulated compared to those in Notch mice. Our study suggests that the immune system and inflammation play an important role in HCC development in HSV-tk mice. Specifically, increased expression of immune-inflammatory-related genes is characteristic of HSV-tk mice and that inflammation-induced cell cycle activation maybe a precursory step to cancer. The HSV-tk mouse provides a suitable model for the study of the relationship between immune-inflammation and HCC, and their underlying mechanism for the development of therapeutic application in the future.

HDAC3-mediated silencing of miR-451 decreases chemosensitivity of patients with metastatic castration-resistant prostate cancer by targeting NEDD9

Background:

Treatment of metastatic castration-resistant prostate cancer (mCRPC) with docetaxel often fails due to the emergence of chemoresistance. Thus, restoring chemosensitivity to docetaxel-based therapies remains a challenge in mCRPC treatment.

Methods:

microRNA (miR)-451 expression was measured in docetaxel-treated prostate cancer cells and tumor tissues by quantitative reverse-transcription polymerase chain reaction . Cell-counting kit 8 assay was performed to determine docetaxel chemoresistance. Neural-precursor-cell-expressed developmentally downregulated protein 9 (NEDD9) was identified as a novel target of miR-451 by dual-luciferase reporter system. Chromatin immunoprecipitation and co-immunoprecipitation assay were performed to confirm that histone deacetylase 3 (HDAC3)/Sp1 (a highly evolutionarily conserved transcription factor) interacted with the Sp1 binding sites in miR-451 promoter.

Results:

miR-451 was found to be silenced in docetaxel-treated prostate cancer cells and mCRPC tissues. Low miR-451 expression was closely associated with a high Gleason score, high Eastern Cooperative Oncology Group performance status score, visceral metastasis and poor prognosis. Low expression of miR-451 was significantly correlated with short progression-free survival (PFS) and overall survival (OS) according to Kaplan–Meier analysis, and miR-451 was determined to be an independent poor prognostic factor for PFS and OS in mCRPC patients by univariate and multivariate Cox regression analyses. NEDD9 was identified as a new and functional target of miR-451. Restoration of NEDD9 partially reversed the effects of miR-451 on enhancing chemosensitivity of prostate cancer cells. HDAC3 was confirmed to be involved in silencing of miR-451 expression in prostate cancer cells.

Conclusions:

The current data revealed a new HDAC3/Sp1/miR-451/NEDD9 signaling axis that regulates the chemosensitivity of prostate cancer cells and represents a novel therapeutic target for chemosensitizing mCRPC.

Identification of The Aberrantly Expressed LncRNAs in Hepatocellular Carcinoma: A Bioinformatics Analysis Based on RNA-sequencing

Hepatocellular carcinoma (HCC) is one of the most prevalent subtypes of liver cancer worldwide. LncRNAs have been demonstrated to be associated with the progression of HCC, but a systematic identification and characterization of their clinical roles and molecular mechanisms in HCC has not been conducted. In this study, the aberrantly expressed lncRNAs in HCC tissues were analyzed based on TCGA RNA-seq data. 1162 lncRNAs were found to be aberrantly expressed in HCC tissues, including 232 down-regulated lncRNAs and 930 up-regulated lncRNAs. The top 5 lncRNAs with the highest diagnostic accuracy were further analyzed to evaluate their clinical value and potential mechanism in HCC. Kaplan-Meier curves showed that higher expressions of DDX11-AS1 and AC092171.4 were in correlation with poorer survival in HCC patients. Significant difference was also observed when comparing the expression levels of DDX11-AS1 and SFTA1P in different clinical parameters (p < 0.05). GO analysis showed that genes regulated by the 5 lncRNAs were enriched in certain pathways, such as PI3K pathway. Moreover, GSEA analysis on the expression of DDX11-AS1 showed that DDX11-AS1 affected the gene expressions involved in HCC proliferation, differentiation and cell cycle, indicating an essential role of DDX11-AS1 in hepatocarcinogenesis.

The immunology of hepatocellular carcinoma

In contrast to most other malignancies, hepatocellular carcinoma (HCC), which accounts for approximately 90% of primary liver cancers, arises almost exclusively in the setting of chronic inflammation. Irrespective of etiology, a typical sequence of chronic necroinflammation, compensatory liver regeneration, induction of liver fibrosis and subsequent cirrhosis often precedes hepatocarcinogenesis. The liver is a central immunomodulator that ensures organ and systemic protection while maintaining immunotolerance. Deregulation of this tightly controlled liver immunological network is a hallmark of chronic liver disease and HCC. Notably, immunotherapies have raised hope for the successful treatment of advanced HCC. Here we summarize the roles of specific immune cell subsets in chronic liver disease, with a focus on non-alcoholic steatohepatitis and HCC. We review new advances in immunotherapeutic approaches for the treatment of HCC and discuss the challenges posed by the immunotolerant hepatic environment and the dual roles of adaptive and innate immune cells in HCC.

Impact of glutathione peroxidase 4 on cell proliferation, angiogenesis and cytokine production in hepatocellular carcinoma

Insufficient supplementation with the micronutrient selenium and persistent hepatic inflammation predispose to hepatocellular carcinoma (HCC). Inflammation-associated reactive oxygen species attack membrane lipids and form lipid hydroperoxides able to propagate oxidative hepatic damage. Selenium-containing enzyme glutathione peroxidase 4 (GPx4) antagonizes this damage by reducing lipid hydroperoxides to respective hydroxides. However, the role of GPx4 in HCC remains elusive. We generated two human HCC cell lines with stable overexpression of GPx4, performed xenotransplantation into NOD.Cg-Prkdc^scidIl2rg^tm1Wjl/SzJ (NSG) host mice and characterized the tumors formed. The experimental data were verified using gene expression data from two independent HCC patient cohorts. GPx4 overexpression protected from oxidative stress and reduced intracellular free radical level. GPx4-overexpressing cells displayed impaired tumor growth, reduced proliferation, altered angiogenesis and decreased expression of clinically relevant cytokine interleukin-8 and C-reactive protein. Moreover, GPx4 overexpression impaired migration of endothelial cells in vitro, and enhanced expression of thrombospondin 1, an endogenous inhibitor of angiogenesis. In patients, GPx4 expression in tumors positively correlated with survival and was linked to pathways which regulate cell proliferation, motility, tissue remodelling, immune response and M1 macrophage polarization. The patient data largely confirmed experimental findings especially in a subclass of poor prognosis tumors with high proliferation. GPx4 suppresses formation and progression of HCC by inhibition of angiogenesis and tumor cell proliferation as well as by immune-mediated mechanisms. Modification of GPx4 expression may represent a novel tool for HCC prevention or treatment.

DNAJB1-PRKACA fusion kinase interacts with β-catenin and the liver regenerative response to drive fibrolamellar hepatocellular carcinoma

A segmental deletion resulting in DNAJB1-PRKACA gene fusion is now recognized as the signature genetic event of fibrolamellar hepatocellular carcinoma (FL-HCC), a rare but lethal liver cancer that primarily affects adolescents and young adults. Here we implement CRISPR-Cas9 genome editing and transposon-mediated somatic gene transfer to demonstrate that expression of either the endogenous fusion protein or a chimeric cDNA leads to the formation of indolent liver tumors in mice that closely resemble human FL-HCC. Notably, overexpression of the wild-type PRKACA was unable to fully recapitulate the oncogenic activity of DNAJB1-PRKACA, implying that FL-HCC does not simply result from enhanced PRKACA expression. Tumorigenesis was significantly enhanced by genetic activation of β-catenin, an observation supported by evidence of recurrent Wnt pathway mutations in human FL-HCC, as well as treatment with the hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine, which causes tissue injury, inflammation, and fibrosis. Our study validates the DNAJB1-PRKACA fusion kinase as an oncogenic driver and candidate drug target for FL-HCC, and establishes a practical model for preclinical studies to identify strategies to treat this disease.

Down-regulation of hepatocyte nuclear factor-4α and defective zonation in livers expressing mutant Z α1-antitrypsin

α₁ -Antitrypsin (AAT) deficiency is one of the most common genetic disorders and the liver disease due to the Z mutant of AAT (ATZ) is a prototype of conformational disorder due to protein misfolding with consequent aberrant intermolecular protein aggregation. In the present study, we found that livers of PiZ transgenic mice expressing human ATZ have altered expression of a network of hepatocyte transcriptional factors, including hepatocyte nuclear factor-4α, that is early down-regulated and induces a transcriptional repression of ATZ expression. Reduced hepatocyte nuclear factor-4α was associated with activation of β-catenin, which regulates liver zonation. Livers of PiZ mice and human patients with AAT deficiency were both found to have a severe perturbation of liver zonation. Functionally, PiZ mice showed a severe defect of ureagenesis, as shown by increased baseline ammonia, and reduced urea production and survival after an ammonia challenge. Down-regulation of hepatocyte nuclear factor-4α expression and defective zonation in livers have not been recognized so far as features of the liver disease caused by ATZ and are likely involved in metabolic disturbances and in the increased risk of hepatocellular carcinoma in patients with AAT deficiency.

CONCLUSION

The findings of this study are consistent with the concept that abnormal AAT protein conformation and intrahepatic accumulation have broad effects on metabolic liver functions. (Hepatology 2017;66:124-135).

Kupffer Cell-Derived Tnf Triggers Cholangiocellular Tumorigenesis through JNK due to Chronic Mitochondrial Dysfunction and ROS

Intrahepatic cholangiocarcinoma (ICC) is a highly malignant, heterogeneous cancer with poor treatment options. We found that mitochondrial dysfunction and oxidative stress trigger a niche favoring cholangiocellular overgrowth and tumorigenesis. Liver damage, reactive oxygen species (ROS) and paracrine tumor necrosis factor (Tnf) from Kupffer cells caused JNK-mediated cholangiocellular proliferation and oncogenic transformation. Anti-oxidant treatment, Kupffer cell depletion, Tnfr1 deletion, or JNK inhibition reduced cholangiocellular pre-neoplastic lesions. Liver-specific JNK1/2 deletion led to tumor reduction and enhanced survival in Akt/Notch- or p53/Kras-induced ICC models. In human ICC, high Tnf expression near ICC lesions, cholangiocellular JNK-phosphorylation, and ROS accumulation in surrounding hepatocytes are present. Thus, Kupffer cell-derived Tnf favors cholangiocellular proliferation/differentiation and carcinogenesis. Targeting the ROS/Tnf/JNK axis may provide opportunities for ICC therapy.

Liver Cancer Cell of Origin, Molecular Class, and Effects on Patient Prognosis

Primary liver cancer is the second leading cause of cancer-related death worldwide and therefore a major public health challenge. We review hypotheses of the cell of origin of liver tumorigenesis and clarify the classes of liver cancer based on molecular features and how they affect patient prognosis. Primary liver cancer comprises hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (iCCA), and other rare tumors, notably fibrolamellar carcinoma and hepatoblastoma. The molecular and clinical features of HCC versus iCCA are distinct, but these conditions have overlapping risk factors and pathways of oncogenesis. A better understanding of the cell types originating liver cancer can aid in exploring molecular mechanisms of carcinogenesis and therapeutic options. Molecular studies have identified adult hepatocytes as the cell of origin. These cells have been proposed to transform directly into HCC cells (via a sequence of genetic alterations), to dedifferentiate into hepatocyte precursor cells (which then become HCC cells that express progenitor cell markers), or to transdifferentiate into biliary-like cells (which give rise to iCCA). Alternatively, progenitor cells also give rise to HCCs and iCCAs with markers of progenitor cells. Advances in genome profiling and next-generation sequencing have led to the classification of HCCs based on molecular features and assigned them to categories such as proliferation-progenitor, proliferation-transforming growth factor β, and Wnt-catenin β1. iCCAs have been assigned to categories of proliferation and inflammation. Overall, proliferation subclasses are associated with a more aggressive phenotype and poor outcome of patients, although more specific signatures have refined our prognostic abilities. Analyses of genetic alterations have identified those that might be targeted therapeutically, such as fusions in the FGFR2 gene and mutations in genes encoding isocitrate dehydrogenases (in approximately 60% of iCCAs) or amplifications at 11q13 and 6p21 (in approximately 15% of HCCs). Further studies of these alterations are needed before they can be used as biomarkers in clinical decision making.