Functional and genetic deconstruction of the cellular origin in liver cancer

NUSAP1 Promotes Immunity and Apoptosis by the SHCBP1/JAK2/STAT3 Phosphorylation Pathway to Induce Dendritic Cell Generation in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and is associated with high morbidity and mortality rates. The aims of this study were to investigate the immune-promoting action of nucleolar and spindle-associated protein 1 (NUSAP1) and identify an immunotherapy target for HCC. The Cancer Genome Atlas (TCGA) was used to analyze interaction molecules and immune correlation. The interaction between NUSAP1 and SHC binding and spindle associated 1 (SHCBP1) was examined. The role of the SHCBP1/Janus kinase 2/signal transducer and activator of transcription 3 (SHCBP1/JAK2/STAT3) pathway in this process was explored. After co-culture with HCC cell lines, the differentiation of peripheral blood mononuclear cells (PBMCs) into dendritic cells (DC) was evaluated by measuring the expression of surface factors CD1a and CD86. Pathological tissues from 50 patients with HCC were collected to validate the results of cell experiments. The expression levels of CD1a and CD86 in tissues were also determined. The results show that NUSAP1 interacted with SHCBP1 and was positively correlated with DC. In HCC cell lines, an interaction was observed between NUSAP1 and SHCBP1. It was verified that NUSAP1 inhibited the JAK2/STAT3 phosphorylation pathway by blocking SHCBP1. After co-culture, the levels of CD1a and CD86 in PBMC were elevated. In the clinical specimens, CD1a and CD86 expression levels were significantly higher in the high-NUSAP1 group versus the low-NUSAP1 group. In Summary, NUSAP1 enhanced immunity by inhibiting the SHCBP1/JAK2/STAT3 phosphorylation pathway and promoted DC generation and HCC apoptosis. NUSAP1 may be a target of immunotherapy for HCC.

Hepatitis B virus X protein and TGF-β: partners in the carcinogenic journey of hepatocellular carcinoma

Hepatitis B infection is substantially associated with the development of liver cancer globally, with the prevalence of hepatocellular carcinoma (HCC) cases exceeding 50%. Hepatitis B virus (HBV) encodes the Hepatitis B virus X (HBx) protein, a pleiotropic regulatory protein necessary for the transcription of the HBV covalently closed circular DNA (cccDNA) microchromosome. In previous studies, HBV-associated HCC was revealed to be affected by HBx in multiple signaling pathways, resulting in genetic mutations and epigenetic modifications in proto-oncogenes and tumor suppressor genes. In addition, transforming growth factor-β (TGF-β) has dichotomous potentials at various phases of malignancy as it is a crucial signaling pathway that regulates multiple cellular and physiological processes. In early HCC, TGF-β has a significant antitumor effect, whereas in advanced HCC, it promotes malignant progression. TGF-β interacts with the HBx protein in HCC, regulating the pathogenesis of HCC. This review summarizes the respective and combined functions of HBx and TGB-β in HCC occurrence and development.

PARP-1 selectively impairs KRAS-driven phenotypic and molecular features in intrahepatic cholangiocarcinoma

OBJECTIVE

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer with limited therapeutic options. KRAS mutations are among the most abundant genetic alterations in iCCA associated with poor clinical outcome and treatment response. Recent findings indicate that Poly(ADP-ribose)polymerase1 (PARP-1) is implicated in KRAS-driven cancers, but its exact role in cholangiocarcinogenesis remains undefined.

DESIGN

PARP-1 inhibition was performed in patient-derived and established iCCA cells using RNAi, CRISPR/Cas9 and pharmacological inhibition in KRAS-mutant, non-mutant cells. In addition, Parp-1 knockout mice were combined with iCCA induction by hydrodynamic tail vein injection to evaluate an impact on phenotypic and molecular features of Kras-driven and Kras-wildtype iCCA. Clinical implications were confirmed in authentic human iCCA.

RESULTS

PARP-1 was significantly enhanced in KRAS-mutant human iCCA. PARP-1-based interventions preferentially impaired cell viability and tumourigenicity in human KRAS-mutant cell lines. Consistently, loss of Parp-1 provoked distinct phenotype in Kras/Tp53-induced versus Akt/Nicd-induced iCCA and abolished Kras-dependent cholangiocarcinogenesis. Transcriptome analyses confirmed preferential impairment of DNA damage response pathways and replicative stress response mediated by CHK1. Consistently, inhibition of CHK1 effectively reversed PARP-1 mediated effects. Finally, Parp-1 depletion induced molecular switch of KRAS-mutant iCCA recapitulating good prognostic human iCCA patients.

CONCLUSION

Our findings identify the novel prognostic and therapeutic role of PARP-1 in iCCA patients with activation of oncogenic KRAS signalling.

Genetic screening of liver cancer: State of the art

Liver cancer, primarily hepatocellular carcinoma, remains a global health challenge with rising incidence and limited therapeutic options. Genetic factors play a pivotal role in the development and progression of liver cancer. This state-of-the-art paper provides a comprehensive review of the current landscape of genetic screening strategies for liver cancer. We discuss the genetic underpinnings of liver cancer, emphasizing the critical role of risk-associated genetic variants, somatic mutations, and epigenetic alterations. We also explore the intricate interplay between environmental factors and genetics, highlighting how genetic screening can aid in risk stratification and early detection via using liquid biopsy, and advancements in high-throughput sequencing technologies. By synthesizing the latest research findings, we aim to provide a comprehensive overview of the state-of-the-art genetic screening methods for liver cancer, shedding light on their potential to revolutionize early detection, risk assessment, and targeted therapies in the fight against this devastating disease.

Revealing the role of necroptosis microenvironment: FCGBP + tumor-associated macrophages drive primary liver cancer differentiation towards cHCC-CCA or iCCA

Previous research has demonstrated that the conversion of hepatocellular carcinoma (HCC) to intrahepatic cholangiocarcinoma (iCCA) can be stimulated by manipulating the tumor microenvironment linked with necroptosis. However, the specific cells regulating the necroptosis microenvironment have not yet been identified. Additionally, further inquiry into the mechanism of how the tumor microenvironment regulates necroptosis and its impact on primary liver cancer(PLC) progression may be beneficial for precision therapy. We recruited a single-cell RNA sequencing dataset (scRNA-seq) with 34 samples from 4 HCC patients and 3 iCCA patients, and a Spatial Transcriptomic (ST) dataset including one each of HCC, iCCA, and combined hepatocellular-cholangiocarcinoma (cHCC-CCA). Quality control, dimensionality reduction and clustering were based on Seurat software (v4.2.2) process and batch effects were removed by harmony (v0.1.1) software. The pseudotime analysis (also known as cell trajectory) in the single cell dataset was performed by monocle2 software (v2.24.0). Calculation of necroptosis fraction was performed by AUCell (v1.16.0) software. Switch gene analysis was performed by geneSwitches(v0.1.0) software. Dimensionality reduction, clustering, and spatial image in ST dataset were performed by Seurat (v4.0.2). Tumor cell identification, tumor subtype characterization, and cell type deconvolution in spot were performed by SpaCET (v1.0.0) software. Immunofluorescence and immunohistochemistry experiments were used to prove our conclusions. Analysis of intercellular communication was performed using CellChat software (v1.4.0). ScRNA-seq analysis of HCC and iCCA revealed that necroptosis predominantly occurred in the myeloid cell subset, particularly in FCGBP + SPP1 + tumor-associated macrophages (TAMs), which had the highest likelihood of undergoing necroptosis. The existence of macrophages undergoing necroptosis cell death was further confirmed by immunofluorescence. Regions of HCC with poor differentiation, cHCC-CCA with more cholangiocarcinoma features, and the tumor region of iCCA shared spatial colocalization with FCGBP + macrophages, as confirmed by spatial transcriptomics, immunohistochemistry and immunofluorescence. Pseudotime analysis showed that premalignant cells could progress into two directions, one towards HCC and the other towards iCCA and cHCC-CCA. Immunofluorescence and immunohistochemistry experiments demonstrated that the number of macrophages undergoing necroptosis in cHCC-CCA was higher than in iCCA and HCC, the number of macrophages undergoing necroptosis in cHCC-CCA with cholangiocarcinoma features was more than in cHCC-CCA with hepatocellular carcinoma features. Further investigation showed that myeloid cells with the highest necroptosis score were derived from the HCC_4 case, which had a severe inflammatory background on pathological histology and was likely to progress towards iCCA and cHCC-CCA. Switchgene analysis indicated that S100A6 may play a significant role in the progression of premalignant cells towards iCCA and cHCC-CCA. Immunohistochemistry confirmed the expression of S100A6 in PLC, the more severe inflammatory background of the tumor area, the more cholangiocellular carcinoma features of the tumor area, S100A6 expression was higher. The emergence of necroptosis microenvironment was found to be significantly associated with FCGBP + SPP1 + TAMs in PLC. In the presence of necroptosis microenvironment, premalignant cells appeared to transform into iCCA or cHCC-CCA. In contrast, without a necroptosis microenvironment, premalignant cells tended to develop into HCC, exhibiting amplified stemness-related genes (SRGs) and heightened malignancy.

Mechanisms of drug resistance in HCC

HCC comprises ∼80% of primary liver cancer. HCC is the only major cancer for which death rates have not improved over the last 10 years. Most patients are diagnosed with advanced disease when surgical and locoregional treatments are not feasible or effective. Sorafenib, a multikinase inhibitor targeting cell growth and angiogenesis, was approved for advanced unresectable HCC in 2007. Since then, other multikinase inhibitors have been approved. Lenvatinib was found to be noninferior to sorafenib as a first-line agent. Regorafenib, cabozantinib, and ramucirumab were shown to prolong survival as second-line agents. Advances in immunotherapy for HCC have also added hope for patients, but their efficacy remains limited. A large proportion of patients with advanced HCC gain no long-term benefit from systemic therapy due to primary and acquired drug resistance, which, combined with its rising incidence, keeps HCC a highly fatal disease. This review summarizes mechanisms of primary and acquired resistance to therapy and includes methods for bypassing resistance. It addresses recent advancements in immunotherapy, provides new perspectives on the linkage between drug resistance and molecular etiology of HCC, and evaluates the role of the microbiome in drug resistance. It also discusses alterations in signaling pathways, dysregulation of apoptosis, modulations in the tumor microenvironment, involvement of cancer stem cells, changes in drug metabolism/transport, tumor hypoxia, DNA repair, and the role of microRNAs in drug resistance. Understanding the interplay among these factors will provide guidance on the development of new therapeutic strategies capable of improving patient outcomes.

HOXD3 promotes the migration and angiogenesis of hepatocellular carcinoma via modifying hepatocellular carcinoma cells exosome-delivered CCR6 and regulating chromatin conformation of CCL20

Angiogenesis plays an essential role in the microenvironment of hepatocellular carcinoma (HCC). HOXD3 is involved in the metastasis and invasion of HCC cells; Whereas the underlying molecular mechanisms in the microenvironment of HCC remain unknown. Wound healing, transwell invasion, tube formation and spheroid sprouting assays were carried out to identify the effects of HCC-HOXD3-exosomes and genes on the migration of HCC cells. ChIP-PCR was applied to test the binding region of HOXD3 on CCR6, Med15, and CREBBP promoter. Exosome isolation and mRNA-seq were applied to examine the morphological characteristics of exosomes and the contained mRNA in exosomes. Co-IP and Immunofluorescence assays were used to demonstrate the role of CREBBP in the chromatin conformation of CCL20. The nude mice were used to identify the function of genes in regulating migration of HCC in vivo. In this study, integrated cellular and bioinformatic analyses revealed that HOXD3 targeted the promoter region of CCR6 and induced its transcription. CCR6 was delivered by exosomes to endothelial cells and promoted tumour migration. Overexpression of CCR6 promoted metastasis, invasion in HCCs and angiogenesis in endothelial cells (ECs), whereas its downregulation suppressed these functions. The role of HOXD3 in the metastasis and invasion of HCC cells was reversed after the suppression of CCR6. Furthermore, CCL20 was demonstrated as the ligand of CCR6, and its high expression was found in HCC tissues and cells, which was clinically associated with the poor prognosis of HCC. Mechanistically, HOXD3 targets the promoter regions of CREBBP and Med15, which affect CCL20 chromatin conformation by regulating histone acetylation and expression of Pol II to enhance the migration of HCCs. This study demonstrated the function of the HOXD3-CREBBP/Med15-CCL20-CCR6 axis in regulating invasion and migration in HCC, thus providing new therapeutic targets for HCC.

Cost-effectiveness analysis of Tislelizumab vs Sorafenib as the first-line treatment of unresectable hepatocellular carcinoma

BACKGROUND

To evaluate the cost-effectiveness of Tislelizumab vs Sorafenib as the first-line treatment of unresectable hepatocellular carcinoma (HCC) from the perspective of the Chinese health service system.

METHODS

A lifetime partitioned survival model (PSM) was developed to cost-effectively analyze Tislelizumab vs Sorafenib as the first-line treatment of unresectable HCC. The clinical and safety data were derived from a recently randomized clinical trial (RATIONALE-301). Utilities were collected from the published literature. Costs were obtained from an open-access database (http://www.yaozh.com) and previous studies. The model cycle was 21 days, according to the RATIONALE-301 study, and the simulation period was patients' lifetime. Long-term direct medical costs and quality-adjusted life-years (QALYs) were determined. The incremental cost-effectiveness ratio (ICER) was used as the evaluation index. one-way sensitivity analysis (OSWA) and probabilistic sensitivity analysis (PSA) were used to analyze the uncertainty of parameters and to adjust and verify the stability of the baseline results.

RESULTS

The Tislelizumab group generated a cost of $39,746.34 and brought health benefits to 2.146 QALYs, while the cost and utility of the Sorafenib group were $26750.95 and 1.578 QALYs, respectively. The Tislelizumab group increased QALYs by 0.568, the incremental cost was $12995.39, and the ICER was $22869.64/QALY, lower than the willingness to pay threshold (WTP). OSWA results showed that the utility of progressed disease (PD), cost of Camrelizumab, and cost of Tislelizumab were the main factors affecting the ICER. PSA results showed that, within 1000 times the Monte Carlo simulation, the cost of the Tislelizumab group was lower than three times the per capita gross domestic product (GDP) of China ($37653/QALY). The cost-effectiveness acceptability curves (CEAC) revealed that when WTP was no less than $12251.00, the Tislelizumab group was the dominant scheme, and the economic advantage grew with an increasing WTP. When WTP ≥ $19000.00, the Tislelizumab group became the absolute economic advantage.

CONCLUSION

Under the current economic conditions in China, the Tislelizumab therapeutic scheme is more cost-effective than the Sorafenib therapeutic scheme for treating patients with unresectable HCC.

WNT/β-catenin signaling in hepatocellular carcinoma: The aberrant activation, pathogenic roles, and therapeutic opportunities

Hepatocellular carcinoma (HCC) is a liver cancer, highly heterogeneous both at the histopathological and molecular levels. It arises from hepatocytes as the result of the accumulation of numerous genomic alterations in various signaling pathways, including canonical WNT/β-catenin, AKT/mTOR, MAPK pathways as well as signaling associated with telomere maintenance, p53/cell cycle regulation, epigenetic modifiers, and oxidative stress. The role of WNT/β-catenin signaling in liver homeostasis and regeneration is well established, whereas in development and progression of HCC is extensively studied. Herein, we review recent advances in our understanding of how WNT/β-catenin signaling facilitates the HCC development, acquisition of stemness features, metastasis, and resistance to treatment. We outline genetic and epigenetic alterations that lead to activated WNT/β-catenin signaling in HCC. We discuss the pivotal roles of CTNNB1 mutations, aberrantly expressed non-coding RNAs and complexity of crosstalk between WNT/β-catenin signaling and other signaling pathways as challenging or advantageous aspects of therapy development and molecular stratification of HCC patients for treatment.

Prognostic value and gene regulatory network of CMSS1 in hepatocellular carcinoma

BACKGROUND

Cms1 ribosomal small subunit homolog (CMSS1) is an RNA-binding protein that may play an important role in tumorigenesis and development.

OBJECTIVE

RNA-seq data from the GEPIA database and the UALCAN database were used to analyze the expression of CMSS1 in liver hepatocellular carcinoma (LIHC) and its relationship with the clinicopathological features of the patients.

METHODS

LinkedOmics was used to identify genes associated with CMSS1 expression and to identify miRNAs and transcription factors significantly associated with CMSS1 by GSEA.

RESULTS

The expression level of CMSS1 in hepatocellular carcinoma tissues was significantly higher than that in normal tissues. In addition, the expression level of CMSS1 in advanced tumors was significantly higher than that in early tumors. The expression level of CMSS1 was higher in TP53-mutated tumors than in non-TP53-mutated tumors. CMSS1 expression levels were strongly correlated with disease-free survival (DFS) and overall survival (OS) in patients with LIHC, and high CMSS1 expression predicted poorer OS (P< 0.01) and DFS (P< 0.01). Meanwhile, our results suggested that CMSS1 is associated with the composition of the immune microenvironment of LIHC.

CONCLUSIONS

The present study suggests that CMSS1 is a potential molecular marker for the diagnosis and prognostic of LIHC.

Stemness markers in hepatocellular carcinoma of Eastern vs. Western population: Etiology matters?

Hepatocellular carcinoma (HCC) is one of the most common cancers with a high mortality rate. HCC development is associated with its underlying etiologies, mostly caused by infection of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV), alcohol, non-alcoholic fatty liver disease, and exposure to aflatoxins. These variables, together with human genetic susceptibility, contribute to HCC molecular heterogeneity, including at the cellular level. HCC initiation, tumor recurrence, and drug resistance rates have been attributed to the presence of liver cancer stem cells (CSC). This review summarizes available data regarding whether various HCC etiologies may be associated to the appearance of CSC biomarkers. It also described the genetic variations of tumoral tissues obtained from Western and Eastern populations, in particular to the oncogenic effect of HBV in the human genome.

A comprehensive analysis of the potential role of necroptosis in hepatocellular carcinoma using single-cell RNA Seq and bulk RNA Seq

PURPOSE

Necroptosis plays an essential role in oncogenesis and tumor progression in hepatocellular carcinoma (HCC). This study aimed to investigate the role of necroptosis in the development and progression of HCC. Specifically, we constructed a prognostic prediction model using necroptosis-associated genes (NAGs) to predict patient outcomes.

METHODS

Using data from The Cancer Genome Atlas (TCGA) database, we analyzed gene expression and clinical data. We identified a 5-gene model associated with NAGs and explored genetic features and immune cell infiltration using the CIBERSORT algorithm. In addition, we conducted single-cell RNA sequencing to investigate the potential role of necroptosis in HCC.

RESULTS

We constructed a 5-gene prognostic model based on NAGs that demonstrated excellent predictive accuracy in both training and validation sets. Using multifactorial cox regression analysis, we confirmed the risk score derived from the model as an independent predictor of prognosis, surpassing other clinical characteristics. Patients with high risk scores had significantly worse prognosis than those with low risk scores. To enhance the clinical utility of the necroptosis score, we constructed an accurate nomogram. Additionally, we compared metabolic pathway and immune microenvironment differences between HCC tumors with high and low risk scores. Our single-cell RNA sequencing analyses revealed that necroptosis in HCC was primarily associated with a specific subset of macrophages.

CONCLUSIONS

Our study revealed the presence of two distinct necroptosis subtypes in HCC and developed a robust prognostic model with exceptional predictive accuracy. We observed significantly higher infiltration of M0 macrophages in the high-risk group. We propose that rescuing cytochrome c metabolism in HCC could serve as a potential therapeutic strategy. Furthermore, at a single-cell resolution, our analysis identified myeloid cells as the primary cells exhibiting necroptosis. Specifically, macrophages expressing CD5L, CETP, and MARCO, which may belong to a subset of tissue-resident macrophages, were found to be highly susceptible to necroptosis. These findings suggest the involvement of this specific macrophage subset in potential antitumor therapies. Our study provides novel insights into predicting patient prognosis and developing personalized therapeutic approaches for HCC.

Exosome-transported circHDAC1_004 Promotes Proliferation, Migration, and Angiogenesis of Hepatocellular Carcinoma by the miR-361-3p/NACC1 Axis

Background and Aims

Hepatocellular carcinoma (HCC) is among the most common malignant tumors globally. Circular RNAs (circRNAs), as a type of noncoding RNAs, reportedly participate in various tumor biological processes. However, the role of circHDAC1_004 in HCC remains unclear. Thus, we aimed to explore the role and the underlying mechanisms of circHDAC1_004 in the development and progression of HCC.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect circHDAC1_004 expression (circ_0005339) in HCC. Sanger sequencing and agarose gel electrophoresis were used to determine the structure of circHDAC1_004. In vitro and in vivo experiments were used to determine the biological function of circHDAC1_004 in HCC. Herein, qRT-PCR, RNA immunoprecipitation, western blotting, and a luciferase reporter assay were used to explore the relationships among circHDAC1_004, miR-361-3p, and NACC1.

Results

circHDAC1_004 was upregulated in HCC and significantly associated with poor overall survival. circHDAC1_004 promoted HCC cell proliferation, stemness, migration, and invasion. In addition, circHDAC1_004 upregulated human umbilical vein endothelial cells (HUVECs) and promoted angiogenesis through exosomes. circHDAC1_004 promoted NACC1 expression and stimulated the epithelial-mesenchymal transition pathway by sponging miR-361-3p.

Conclusions

We found that circHDAC1_004 overexpression enhanced the proliferation, stemness, and metastasis of HCC via the miR-361-3p/NACC1 axis and promoted HCC angiogenesis through exosomes. Our findings may help develop a possible therapeutic strategy for HCC.

Cellular senescence-related genes: predicting prognosis in hepatocellular carcinoma

Recent studies have shown that the high incidence and low cure rate of hepatocellular carcinoma (HCC) have not improved significantly. Surgery and liver transplantation are the mainstays of prolonging the survival of HCC patients. However, the surgical resection rate of HCC patients is very low, and even after radical surgical resection, the recurrence rate at 5 years postoperatively remains high and the prognosis is very poor, so more treatment options are urgently needed. Increasing evidence suggests that cellular senescence is not only related to cancer development but may also be one of its primary driving factors. We aimed to establish a prognostic signature of senescence-associated genes to predict the prognosis and therapeutic response of HCC patients. The aim of this study was to develop a risk model associated with cellular senescence and to search for potential strategies to treat HCC. We divided HCC patients into two clusters and identified differentially expressed genes (DEGs) between clusters. In this study, low-risk patients had a better prognosis, higher levels of immune cell infiltration, and better efficacy to fluorouracil, Paclitaxel and Cytarabine chemotherapy compared to high-risk patients. To further identify potential biomarkers for HCC, we further validated the expression levels of the four signature genes in HCC and neighbouring normal tissues by in vitro experiments. In conclusion, we identified and constructed a relevant prognostic signature, which performed well in predicting the survival and treatment response of HCC patients. This helps to differentiate between low-score and high-risk HCC, and the results may contribute to precise treatment protocols in clinical practice.

A human pilot study on positive electrostatic charge effects in solid tumors of the late-stage metastatic patients

Background

Correlative interactions between electrical charges and cancer cells involve important unknown factors in cancer diagnosis and treatment. We previously reported the intrinsic suppressive effects of pure positive electrostatic charges (PEC) on the proliferation and metabolism of invasive cancer cells without any effect on normal cells in cell lines and animal models. The proposed mechanism was the suppression of pro-caspases 3 and 9 with an increase in Bax/Bcl2 ratio in exposed malignant cells and perturbation induced in the KRAS pathway of malignant cells by electrostatic charges due to the phosphate molecule electrostatic charge as the trigger of the pathway. This study aimed to examine PECs as a complementary treatment for patients with different types of solid metastatic tumors, who showed resistance to chemotherapy and radiotherapy.

Methods

In this study, solid metastatic tumors of the end-stage patients (n = 41) with various types of cancers were locally exposed to PEC for at least one course of 12 days. The patient's signs and symptoms, the changes in their tumor size, and serum markers were followed up from 30 days before positive electrostatic charge treating (PECT) until 6 months after the study.

Results

Entirely, 36 patients completed the related follow-ups. Significant reduction in tumor sizes and cancer-associated enzymes as well as improvement in cancer-related signs and symptoms and patients' lifestyles, without any side effects on other tissues or metabolisms of the body, were observed in more than 80% of the candidates.

Conclusion

PECT induced significant cancer remission in combination with other therapies. Therefore, this non-ionizing radiation would be a beneficial complementary therapy, with no observable side effects of ionizing radiotherapy, such as post-radiation inflammation.

Past, present, and future of chemically induced hepatocarcinogenesis rodent models: Perspectives concerning classic and new cancer hallmarks

Hepatocellular carcinoma (HCC), the main primary liver cancer, accounts for 5 % of all incident cases and 8.4 % of all cancer-related deaths worldwide. HCC displays a spectrum of environmental risk factors (viral chronic infections, aflatoxin exposure, alcoholic- and nonalcoholic fatty liver diseases) that result in molecular complexity and heterogeneity, contributing to a rising epidemiological burden, poor prognosis, and non-satisfactory treatment options. The emergence of HCC (i.e., hepatocarcinogenesis) is a multistep and complex process that addresses many (epi)genetic alterations and phenotypic traits, the so-called cancer hallmarks. "Polymorphic microbiomes", "epigenetic reprogramming", "senescent cells" and "unlocking phenotypic plasticity" are trending hallmarks/enabling features in cancer biology. As the main molecular drivers of HCC are still undruggable, chemically induced in vivo models of hepatocarcinogenesis are useful tools in preclinical research. Thus, this narrative review aimed at recapitulating the basic features of chemically induced rodent models of hepatocarcinogenesis, eliciting their permanent translational value regarding the "classic" and the "new" cancer hallmarks/enabling features. We gathered state-of-art preclinical evidence on non-cirrhotic, inflammation-, alcoholic liver disease- and nonalcoholic fatty liver-associated HCC models, demonstrating that these bioassays indeed express the recently added hallmarks, as well as reflect the interplay between classical and new cancer traits. Our review demonstrated that these protocols remain valuable for translational preclinical application, as they recapitulate trending features of cancer science. Further "omics-based" approaches are warranted while multimodel investigations are encouraged in order to avoid "model-biased" responses.

System analysis based on the lysosome-related genes identifies HPS4 as a novel therapy target for liver hepatocellular carcinoma

Background

Liver cancer is a leading cause of cancer-related deaths worldwide. Lysosomal dysfunction is implicated in cancer progression; however, prognostic prediction models based on lysosome-related genes (LRGs) are lacking in liver cancer. This study aimed to establish an LRG-based model to improve prognosis prediction and explore potential therapeutic targets in liver cancer.

Methods

Expression profiles of 61 LRGs were analyzed in The Cancer Genome Atlas liver cancer cohorts. There were 14 LRGs identified, and their association with clinical outcomes was evaluated. Unsupervised clustering, Cox regression, and functional assays were performed.

Results

Patients were classified into high-risk and low-risk subgroups based on the 14 LRGs. The high-risk group had significantly worse overall survival. Aberrant immune infiltration and checkpoint expression were observed in the high-risk group. Furthermore, HPS4 was identified as an independent prognostic indicator. Knockdown of HPS4 suppressed liver cancer cell proliferation and induced apoptosis.

Conclusion

This study developed an LRG-based prognostic model to improve risk stratification in liver cancer. The potential value of HPS4 as a therapeutic target and biomarker was demonstrated. Regulation of HPS4 may offer novel strategies for precision treatment in liver cancer patients.

MYC determines lineage commitment in KRAS-driven primary liver cancer development

BACKGROUND & AIMS

Primary liver cancer (PLC) comprises hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), two frequent and lethal tumour types that differ regarding their tumour biology and responses to cancer therapies. Liver cells harbour a high degree of cellular plasticity and can give rise to either HCC or iCCA. However, little is known about the cell-intrinsic mechanisms directing an oncogenically transformed liver cell to either HCC or iCCA. The scope of this study was to identify cell-intrinsic factors determining lineage commitment in PLC.

METHODS

Cross-species transcriptomic and epigenetic profiling was applied to murine HCCs and iCCAs and to two human PLC cohorts. Integrative data analysis comprised epigenetic Landscape In Silico deletion Analysis (LISA) of transcriptomic data and Hypergeometric Optimization of Motif EnRichment (HOMER) analysis of chromatin accessibility data. Identified candidate genes were subjected to functional genetic testing in non-germline genetically engineered PLC mouse models (shRNAmir knockdown or overexpression of full-length cDNAs).

RESULTS

Integrative bioinformatic analyses of transcriptomic and epigenetic data pinpointed the Forkhead-family transcription factors FOXA1 and FOXA2 as MYC-dependent determination factors of the HCC lineage. Conversely, the ETS family transcription factor ETS1 was identified as a determinant of the iCCA lineage, which was found to be suppressed by MYC during HCC development. Strikingly, shRNA-mediated suppression of FOXA1 and FOXA2 with concomitant ETS1 expression fully switched HCC to iCCA development in PLC mouse models.

CONCLUSIONS

The herein reported data establish MYC as a key determinant of lineage commitment in PLC and provide a molecular explanation why common liver-damaging risk factors such as alcoholic or non-alcoholic steatohepatitis can lead to either HCC or iCCA.

IMPACT AND IMPLICATIONS

Liver cancer is a major health problem and comprises hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), two frequent and lethal tumour types that differ regarding their morphology, tumour biology, and responses to cancer therapies. We identified the transcription factor and oncogenic master regulator MYC as a switch between HCC and iCCA development. When MYC levels are high at the time point when a hepatocyte becomes a tumour cell, an HCC is growing out. Conversely, if MYC levels are low at this time point, the result is the outgrowth of an iCCA. Our study provides a molecular explanation why common liver-damaging risk factors such as alcoholic or non-alcoholic steatohepatitis can lead to either HCC or iCCA. Furthermore, our data harbour potential for the development of better PLC therapies.

Tumor purity-associated genes influence hepatocellular carcinoma prognosis and tumor microenvironment

Introduction

Tumor purity takes on critical significance to the progression of solid tumors. The aim of this study was at exploring potential prognostic genes correlated with tumor purity in hepatocellular carcinoma (HCC) by bioinformatics analysis.

Methods

The ESTIMATE algorithm was applied for determining the tumor purity of HCC samples from The Cancer Genome Atlas (TCGA). The tumor purity-associated genes with differential expression (DEGs) were identified based on overlap analysis, weighted gene co-expression network analysis (WGCNA), and differential expression analysis. The prognostic genes were identified in terms of the prognostic model construction based on the Kaplan-Meier (K-M) survival analysis and Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses. The expression of the above-described genes was further validated by the GSE105130 dataset from the Gene Expression Omnibus (GEO) database. We also characterized the clinical and immunophenotypes of prognostic genes. Gene set enrichment analysis (GSEA) was carried out for exploring the biological signaling pathway.

Results

A total of 26 tumor purity-associated DEGs were identified, which were involved in biological processes such as immune/inflammatory responses and fatty acid elongation. Ultimately, we identified ADCK3, HK3, and PPT1 as the prognostic genes for HCC. Moreover, HCC patients exhibiting higher ADCK3 expression and lower HK3 and PPT1 expressions had a better prognosis. Furthermore, high HK3 and PPT1 expressions and low ADCK3 expression resulted in high tumor purity, high immune score, high stromal score, and high ESTIMATE score. GSEA showed that the abovementioned prognostic genes showed a significant correlation with immune-inflammatory response, tumor growth, and fatty acid production/degradation.

Discussion

In conclusion, this study identified novel predictive biomarkers (ADCK3, HK3, and PPT1) and studied the underlying molecular mechanisms of HCC pathology initially.

DKK1-CKAP4 signal axis promotes hepatocellular carcinoma aggressiveness

Hepatocellular carcinoma (HCC) is the most prevalent malignant liver neoplasm. Despite the advances in diagnosis and treatment, the prognosis of HCC patients remains poor. Cytoskeleton-associated membrane protein 4 (CKAP4) is a receptor of the glycosylated secretory protein Dickkopf-1 (DKK1), and the DKK1-CKAP4 axis is activated in pancreatic, lung, and esophageal cancer cells. Expression of DKK1 and CKAP4 has been examined in HCC in independent studies that yielded contradictory results. In this study, the relationship between the DKK1-CKAP4 axis and HCC was comprehensively examined. In 412 HCC cases, patients whose tumors were positive for both DKK1 and CKAP4 had a poor prognosis compared to those who were positive for only one of these markers or negative for both. Deletion of either DKK1 or CKAP4 inhibited HCC cell growth. In contrast to WT DKK1, DKK1 lacking the CKAP4 binding region did not rescue the phenotypes caused by DKK1 depletion, suggesting that binding of DKK1 to CKAP4 is required for HCC cell proliferation. Anti-CKAP4 Ab inhibited HCC growth, and its antitumor effect was clearly enhanced when combined with lenvatinib, a multikinase inhibitor. These results indicate that simultaneous expression of DKK1 and CKAP4 is involved in the aggressiveness of HCC, and that the combination of anti-CKAP4 Ab and other therapeutics including lenvatinib could represent a promising strategy for treating advanced HCC.

Non-invasive imaging in the diagnosis of combined hepatocellular carcinoma and cholangiocarcinoma

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare type of primary liver cancer. It is a complex "biphenotypic" tumor type consisting of bipotential hepatic progenitor cells that can differentiate into cholangiocytes subtype and hepatocytes subtype. The prognosis of patients with cHCC-CC is quite poor with its specific and more aggressive nature. Furthermore, there are no definite demographic or clinical features of cHCC-CC, thus a clear preoperative identification and accurate non-invasive imaging diagnostic analysis of cHCC-CC are of great value. In this review, we first summarized the epidemiological features, pathological findings, molecular biological information and serological indicators of cHCC-CC disease. Then we reviewed the important applications of non-invasive imaging modalities-particularly ultrasound (US)-in cHCC-CC, covering both diagnostic and prognostic assessment of patients with cHCC-CC. Finally, we presented the shortcomings and potential outlooks for imaging studies in cHCC-CC.

Molecular characterization-based multi-omics analyses in primary liver cancer using the Japanese version of the genome atlas

BACKGROUND

Primary liver cancer (PLC) is classified into hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and combined hepatocellular and intrahepatic cholangiocarcinoma (CHC). We investigated the genomic landscape of PLC according to the histological classification and established a cross-histological molecular subtyping for PLC by a multi-omics analysis.

METHODS

We analyzed 265 PLC cases with whole-exome sequencing and DNA copy number analyses and 251 cases with gene expression profiling.

RESULTS

The cohort included HCC (n = 223, 84%), ICC (n = 34, 13%), and CHC (n = 8, 3%). Mutation analyses identified histological type-specific driver genes, such as CTNNB1 in HCC and KRAS, IDH1, and PIK3CA in ICC, and ARID1A and KMT2C in CHC. The tumor suppressor gene TP53 mutation was detected in 21.1% of HCC, 16.1% of ICC, and 25.0% of CHC cases. Other well-characterized tumor suppressor genes included RB1, which was mutated in 2.8% of HCC and 3.2% of ICC; and PTEN, which was mutated in 1.4% of HCC, 3.2% of ICC, and 12.5% of CHC cases. DNA copy number analyses identified focal amplifications, with NUF2 (1q23.3) the most frequently detected as an amplified gene in all 3 types (HCC, 3.8%; CHC, 12.5%, ICC, 3.2%). Molecular subtyping for PLC based on the multi-omics analysis identified three subtypes, one of which was associated with recurrence after resection and amplified genes located at chromosome 8q.

CONCLUSIONS

Our dataset serves as a fundamental resource for genomic medicine for PLC in Japan and identified amplified genes located at chromosome 8q as promising therapeutic targets for the subgroup with a poor prognosis.

Tumor decellularization reveals proteomic and mechanical characteristics of the extracellular matrix of primary liver cancer

Tumor initiation and progression are critically dependent on interaction of cancer cells with their cellular and extracellular microenvironment. Alterations in the composition, integrity, and mechanical properties of the extracellular matrix (ECM) dictate tumor processes including cell proliferation, migration, and invasion. Also in primary liver cancer, consisting of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), the dysregulation of the extracellular environment by liver fibrosis and tumor desmoplasia is pertinent. Yet, the exact changes occurring in liver cancer ECM remain uncharacterized and underlying tumor-promoting mechanisms remain largely unknown. Herein, an integrative molecular and mechanical approach is used to extensively characterize the ECM of HCC and CCA tumors by utilizing an optimized decellularization technique. We identified a myriad of proteins in both tumor and adjacent liver tissue, uncovering distinct malignancy-related ECM signatures. The resolution of this approach unveiled additional ECM-related proteins compared to large liver cancer transcriptomic datasets. The differences in ECM protein composition resulted in divergent mechanical properties on a macro- and micro-scale that are tumor-type specific. Furthermore, the decellularized tumor ECM was employed to create a tumor-specific hydrogel that supports patient-derived tumor organoids, which provides a new avenue for personalized medicine applications. Taken together, this study contributes to a better understanding of alterations to composition, stiffness, and collagen alignment of the tumor ECM that occur during liver cancer development.

Targeting PSAT1 to mitigate metastasis in tumors with p53-72Pro variant

The single-nucleotide polymorphism (SNP) of p53, in particular the codon 72 variants, has recently been implicated as a critical regulator in tumor progression. However, the underlying mechanism remains elusive. Here we found that cancer cells carrying codon 72-Pro variant of p53 showed impaired metastatic potential upon serine supplementation. Proteome-wide mapping of p53-interacting proteins uncovered a specific interaction of the codon 72 proline variant (but not p53^72R) with phosphoserine aminotransferase 1 (PSAT1). Interestingly, p53^72P-PSAT1 interaction resulted in dissociation of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) that otherwise bound to p53^72P, leading to subsequent nuclear translocation of PGC-1α and activation of oxidative phosphorylation (OXPHOS) and tricarboxylic acid (TCA) cycle. Depletion of PSAT1 restored p53^72P-PGC-1α interaction and impeded the OXPHOS and TCA function, resulting in mitochondrial dysfunction and metastasis suppression. Notably, pharmacological targeting the PSAT1-p53^72P interaction by aminooxyacetic acid (AOA) crippled the growth of liver cancer cells carrying the p53^72P variant in both in vitro and patient-derived xenograft models. Moreover, AOA plus regorafenib, an FDA-proved drug for hepatocellular carcinoma and colorectal cancer, achieved a better anti-tumor effect on tumors carrying the p53^72P variant. Therefore, our findings identified a gain of function of the p53^72P variant on mitochondrial function and provided a promising precision strategy to treat tumors vulnerable to p53^72P-PSAT1 perturbation.

Criteria for preclinical models of cholangiocarcinoma: scientific and medical relevance

Cholangiocarcinoma (CCA) is a rare malignancy that develops at any point along the biliary tree. CCA has a poor prognosis, its clinical management remains challenging, and effective treatments are lacking. Therefore, preclinical research is of pivotal importance and necessary to acquire a deeper understanding of CCA and improve therapeutic outcomes. Preclinical research involves developing and managing complementary experimental models, from in vitro assays using primary cells or cell lines cultured in 2D or 3D to in vivo models with engrafted material, chemically induced CCA or genetically engineered models. All are valuable tools with well-defined advantages and limitations. The choice of a preclinical model is guided by the question(s) to be addressed; ideally, results should be recapitulated in independent approaches. In this Consensus Statement, a task force of 45 experts in CCA molecular and cellular biology and clinicians, including pathologists, from ten countries provides recommendations on the minimal criteria for preclinical models to provide a uniform approach. These recommendations are based on two rounds of questionnaires completed by 35 (first round) and 45 (second round) experts to reach a consensus with 13 statements. An agreement was defined when at least 90% of the participants voting anonymously agreed with a statement. The ultimate goal was to transfer basic laboratory research to the clinics through increased disease understanding and to develop clinical biomarkers and innovative therapies for patients with CCA.

Circular RNA-0072309 has antitumor influences in Hep3B cell line by targeting microRNA-665

Liver cancer is a malignant tumor that occurs in the liver and has a high mortality rate. We strived to detect the role and mechanism of circRNA-0072309 in liver cancer. Hep3B cell line was transfected with pc-circ and si-circ for viability, colony formation, apoptosis, migration, and invasion tests, which were individually performed by CCK-8, colony formation detection, flow cytometry assay, migration and invasion assays. What is more, the luciferase reporter assay was conducted to determine the target relationship between the circRNA-0072309 and microRNA (miR)-665. The expression of circRNA-0072309 was examined by qRT-PCR. The expression of proteins was examined via western blot. CircRNA-0072309 was lowly expressed in liver cancer tissues and positively associated with 5-year survival rate. The viability, colony formation, invasive and migratory ability were inhibited by abundant circRNA-0072309, which promoted cell apoptosis on the contrary. CircRNA-0072309 knockdown induced opposite effects, but could not affect apoptosis. Overexpressed miR-665 in tumor tissues was targeted and negatively controlled by circRNA-0072309. The PI3K/AKT and Wnt/β-catenin pathways were inhibited by abundant circRNA-0072309. miR-665 overexpression disturbed those effects derived from pc-circ. The circRNA-0072309 had antitumor influences in Hep3B cell line through targeting miR-665 relying on the deactivation of PI3K/AKT and Wnt/β-catenin pathways.

Rhamnetin ameliorates non-alcoholic steatosis and hepatocellular carcinoma in vitro

Non-alcoholic fatty liver (NAFLD) is a widespread disease with various complications including Non-alcoholic steatohepatitis (NASH) that could lead to cirrhosis and ultimately hepatocellular carcinoma (HCC). Up till now there is no FDA approved drug for treatment of NAFLD. Flavonoids such as Rhamnetin (Rhm) have been ascribed effective anti-inflammatory and anti-oxidative properties. Thus, Rhm as a potent flavonoid could target multiple pathological cascades causing NAFLD to prevent its progression into HCC. NAFLD is a multifactorial disease and its pathophysiology is complex and is currently challenged by the ‘Multiple-hit hypothesis’ that includes wider range of comorbidities rather than previously established theory of ‘Two-hit hypothesis’. Herein, we aimed at establishing reliable in vitro NASH models using different mixtures of variable ratios and concentrations of oleic acid (OA) and palmitic acid (PA) combinations using HepG2 cell lines. Moreover, we compared those models in the context of oil red staining, triglyceride levels and their altered downstream molecular signatures for genes involved in de novo lipogenesis, inflammation, oxidative stress and apoptotic machineries as well. Lastly, the effect of Rhm on NASH and HCC models was deeply investigated. Over the 10 NASH models tested, PA 500 µM concentration was the best model to mimic the molecular events of steatosis induced NAFLD. Rhm successfully ameliorated the dysregulated molecular events caused by the PA-induced NASH. Additionally, Rhm regulated inflammatory and oxidative machinery in the HepG2 cancerous cell lines. In conclusion, PA 500 µM concentration is considered an effective in vitro model to mimic NASH. Rhm could be used as a promising therapeutic modality against both NASH and HCC pathogenesis.

Mesenchymal/stromal stem cells: necessary factors in tumour progression

Mesenchymal/stromal stem cells (MSCs) are a crucial component of the tumour microenvironment (TME). They can be recruited from normal tissues into the TME and educated by tumour cells to transform into tumour-associated MSCs, which are oncogenic cells that promote tumour development and progression by impacting or transforming into various kinds of cells, such as immune cells and endothelial cells. Targeting MSCs in the TME is a novel strategy to prevent malignant processes. Exosomes, as communicators, carry various RNAs and proteins and thus link MSCs and the TME, which provides options for improving outcomes and developing targeted treatment.

Consensus subtypes of hepatocellular carcinoma associated with clinical outcomes and genomic phenotypes

BACKGROUND AND AIMS

Although many studies revealed transcriptomic subtypes of HCC, concordance of the subtypes are not fully examined. We aim to examine a consensus of transcriptomic subtypes and correlate them with clinical outcomes.

APPROACH AND RESULTS

By integrating 16 previously established genomic signatures for HCC subtypes, we identified five clinically and molecularly distinct consensus subtypes. STM (STeM) is characterized by high stem cell features, vascular invasion, and poor prognosis. CIN (Chromosomal INstability) has moderate stem cell features, but high genomic instability and low immune activity. IMH (IMmune High) is characterized by high immune activity. BCM (Beta-Catenin with high Male predominance) is characterized by prominent β-catenin activation, low miRNA expression, hypomethylation, and high sensitivity to sorafenib. DLP (Differentiated and Low Proliferation) is differentiated with high hepatocyte nuclear factor 4A activity. We also developed and validated a robust predictor of consensus subtype with 100 genes and demonstrated that five subtypes were well conserved in patient-derived xenograft models and cell lines. By analyzing serum proteomic data from the same patients, we further identified potential serum biomarkers that can stratify patients into subtypes.

CONCLUSIONS

Five HCC subtypes are correlated with genomic phenotypes and clinical outcomes and highly conserved in preclinical models, providing a framework for selecting the most appropriate models for preclinical studies.

Liver tumour immune microenvironment subtypes and neutrophil heterogeneity

The heterogeneity of the tumour immune microenvironment (TIME), organized by various immune and stromal cells, is a major contributing factor of tumour metastasis, relapse and drug resistance^1-3, but how different TIME subtypes are connected to the clinical relevance in liver cancer remains unclear. Here we performed single-cell RNA-sequencing (scRNA-seq) analysis of 189 samples collected from 124 patients and 8 mice with liver cancer. With more than 1 million cells analysed, we stratified patients into five TIME subtypes, including immune activation, immune suppression mediated by myeloid or stromal cells, immune exclusion and immune residence phenotypes. Different TIME subtypes were spatially organized and associated with chemokine networks and genomic features. Notably, tumour-associated neutrophil (TAN) populations enriched in the myeloid-cell-enriched subtype were associated with an unfavourable prognosis. Through in vitro induction of TANs and ex vivo analyses of patient TANs, we showed that CCL4⁺ TANs can recruit macrophages and that PD-L1⁺ TANs can suppress T cell cytotoxicity. Furthermore, scRNA-seq analysis of mouse neutrophil subsets revealed that they are largely conserved with those of humans. In vivo neutrophil depletion in mouse models attenuated tumour progression, confirming the pro-tumour phenotypes of TANs. With this detailed cellular heterogeneity landscape of liver cancer, our study illustrates diverse TIME subtypes, highlights immunosuppressive functions of TANs and sheds light on potential immunotherapies targeting TANs.

Biological roles of the RNA m6A modification and its implications in cancer

The N⁶-Methyladenosine (m⁶A) modification of RNA transcripts is the most prevalent and abundant internal modification in eukaryotic messenger RNAs (mRNAs) and plays diverse and important roles in normal biological processes. Extensive studies have indicated that dysregulated m⁶A modification and m⁶A-associated proteins play critical roles in tumorigenesis and cancer progression. However, m⁶A-mediated physiological consequences often lead to opposite outcomes in a biological context-dependent manner. Therefore, context-related complexity must be meaningfully considered to obtain a comprehensive understanding of RNA methylation. Recently, it has been reported that m⁶A-modified RNAs are closely related to the regulation of the DNA damage response and genomic integrity maintenance. Here, we present an overview of the current knowledge on the m⁶A modification and its function in human cancer, particularly in relation to the DNA damage response and genomic instability.

Studying Hepatitis Virus-Host Interactions in Patient Liver Biopsies

Infectious diseases are a major contributor to human suffering and the associated socioeconomic burden worldwide. A better understanding of human pathogen-host interactions is a prerequisite for the development of treatment strategies aimed at combatting human pathogen-induced diseases. Model systems that faithfully recapitulate the pathogen-host interactions in humans are critical to gain meaningful insight. Unfortunately, such model systems are not yet available for a number of pathogens. The strict tropism of the hepatitis B (HBV) and C (HCV) viruses for the human liver has made it difficult to study their virus-host interactions during the natural history of these infections. In this case, surplus liver biopsy tissue donated by patients provides an opportunity to obtain a snapshot of the phenomenological and molecular aspects of the human liver of chronically HCV or HBV-infected patients. In this review, we will briefly summarize our own efforts over the years to advance our knowledge of the virus-host interactions during the natural history of chronic HCV and HBV infection.

Small-molecule inhibitors, immune checkpoint inhibitors, and more: FDA-approved novel therapeutic drugs for solid tumors from 1991 to 2021

The United States Food and Drug Administration (US FDA) has always been a forerunner in drug evaluation and supervision. Over the past 31 years, 1050 drugs (excluding vaccines, cell-based therapies, and gene therapy products) have been approved as new molecular entities (NMEs) or biologics license applications (BLAs). A total of 228 of these 1050 drugs were identified as cancer therapeutics or cancer-related drugs, and 120 of them were classified as therapeutic drugs for solid tumors according to their initial indications. These drugs have evolved from small molecules with broad-spectrum antitumor properties in the early stage to monoclonal antibodies (mAbs) and antibody‒drug conjugates (ADCs) with a more precise targeting effect during the most recent decade. These drugs have extended indications for other malignancies, constituting a cancer treatment system for monotherapy or combined therapy. However, the available targets are still mainly limited to receptor tyrosine kinases (RTKs), restricting the development of antitumor drugs. In this review, these 120 drugs are summarized and classified according to the initial indications, characteristics, or functions. Additionally, RTK-targeted therapies and immune checkpoint-based immunotherapies are also discussed. Our analysis of existing challenges and potential opportunities in drug development may advance solid tumor treatment in the future.

CDC20 May Serve as a Potential Biomarker-Based Risk Score System in Predicting the Prognosis of Patients with Hepatocellular Carcinoma

Background

The specificity and sensitivity of hepatocellular carcinoma (HCC) diagnostic markers are limited, hindering the early diagnosis and treatment of HCC patients. Therefore, improving prognostic biomarkers for patients with HCC is urgently needed.

Methods

HCC-related datasets were downloaded from the public databases. Differentially expressed genes (DEGs) between HCC and adjacent nontumor liver tissues were then identified. Moreover, the intersection of DEGs in four datasets (GSE138178, GSE77509, GSE84006, and TCGA) was used in the functional enrichment, and module genes were obtained by a coexpression network. Cox and Kaplan-Meier analyses were used to identify overall survival- (OS-) related genes from module genes. Area under the curve (AUC) > 0.9 of OS-related genes was then carried out in order to perform the protein-protein interaction network. The feature genes were identified by least absolute shrinkage and selection operator (LASSO). Furthermore, the hub gene was identified through the univariate Cox model, after which the correlation analysis between the hub gene and pathways was explored. Finally, infiltration in immune cell types in HCC was analyzed.

Results

A total of 2,227 upregulated genes and 1,501 downregulated DEGs were obtained in all four datasets, which were mainly found to be involved in the cell cycle and retinol metabolism. Accordingly, 998 OS-related genes were screened to construct the LASSO model. Finally, 8 feature genes (BUB1, CCNB1, CCNB2, CCNA2, AURKB, CDC20, OIP5, and TTK) were obtained. CDC20 was shown to serve as a poor prognostic gene in HCC and was mainly involved in the cell cycle. Moreover, a positive correlation was noted between the high degree of infiltration with Th2 and CDC20.

Conclusion

High expression of CDC20 predicted poor survival, as potential target in the treatment for HCC.

Exosome-mediated delivery of Cas9 ribonucleoprotein complexes for tissue-specific gene therapy of liver diseases

CRISPR-Cas9 gene editing has emerged as a powerful therapeutic technology, but the lack of safe and efficient in vivo delivery systems, especially for tissue-specific vectors, limits its broad clinical applications. Delivery of Cas9 ribonucleoprotein (RNP) owns competitive advantages over other options; however, the large size of RNPs exceeds the loading capacity of currently available delivery vectors. Here, we report a previously unidentified genome editing delivery system, named exosome^RNP, in which Cas9 RNPs were loaded into purified exosomes isolated from hepatic stellate cells through electroporation. Exosome^RNP facilitated effective cytosolic delivery of RNP in vitro while specifically accumulated in the liver tissue in vivo. Exosome^RNP showed vigorous therapeutic potential in acute liver injury, chronic liver fibrosis, and hepatocellular carcinoma mouse models via targeting p53 up-regulated modulator of apoptosis (PUMA), cyclin E1 (CcnE1), and K (lysine) acetyltransferase 5 (KAT5), respectively. The developed exosome^RNP provides a feasible platform for precise and tissue-specific gene therapies of liver diseases.

Constitutive Activation of the Tumor Suppressor p53 in Hepatocytes Paradoxically Promotes Non-Cell Autonomous Liver Carcinogenesis

In chronic liver diseases (CLD), p53 is constitutively activated in hepatocytes due to various etiologies as viral infection, ethanol exposure, or lipid accumulation. This study was aimed to clarify the significance of p53 activation on the pathophysiology of CLDs. In Kras-mutant liver cancer model, murine double minute 2 (Mdm2), a negative regulator of p53, was specifically deleted in hepatocytes [Alb-Cre KrasLSL-G12D Mdm2fl/fl (LiKM; KrasG12D mutation and Mdm2 loss in the liver)]. Accumulation of p53 and upregulation of its downstream genes were observed in hepatocytes in LiKM mice. LiKM mice showed liver inflammation accompanied by hepatocyte apoptosis, senescence-associated secretory phenotype (SASP), and the emergence of hepatic progenitor cells (HPC). More importantly, Mdm2 deletion promoted non-cell autonomous development of liver tumors. Organoids generated from HPCs harbored tumor-formation ability when subcutaneously inoculated into NOD/Shi-scid/IL2Rγ (null) mice. Treatment with acyclic retinoid suppressed growth of HPCs in vitro and inhibited tumorigenesis in LiKM mice. All of the phenotypes in LiKM mice, including accelerated liver tumorigenesis, were negated by further deletion of p53 in hepatocytes (Alb-Cre KrasLSL-G12D Mdm2fl/fl p53fl/fl). Activation of hepatic p53 was noted in liver biopsy samples obtained from 182 patients with CLD, in comparison with 23 normal liver samples without background liver diseases. In patients with CLD, activity of hepatic p53 was positively correlated with the expression of apoptosis, SASP, HPC-associated genes and tumor incidence in the liver after biopsy. In conclusion, activation of hepatocyte p53 creates a microenvironment prone to tumor formation from HPCs. Optimization of p53 activity in hepatocytes is important to prevent patients with CLD from hepatocarcinogenesis.

SIGNIFICANCE

This study reveals that activation of p53 in hepatocytes promotes liver carcinogenesis derived from HPCs, which elucidates a paradoxical aspect of a tumor suppressor p53 and novel mechanism of liver carcinogenesis. See related commentary by Barton and Lozano, p. 2824.

Inhibition of eIF6 Activity Reduces Hepatocellular Carcinoma Growth: An In Vivo and In Vitro Study

Nonalcoholic fatty liver disease (NAFLD) is characterized by the accumulation of lipids in the liver. Given the high prevalence of NAFLD, its evolution to nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) is of global concern. Therapies for managing NASH-driven HCC can benefit from targeting factors that play a continuous role in NAFLD evolution to HCC. Recent work has shown that postprandial liver translation exacerbates lipid accumulation through the activity of a translation factor, eukaryotic initiation factor 6 (eIF6). Here, we test the effect of eIF6 inhibition on the progression of HCC. Mice heterozygous for eIF6 express half the level of eIF6 compared to wt mice and are resistant to the formation of HCC nodules upon exposure to a high fat/high sugar diet combined with liver damage. Histology showed that nodules in eIF6 het mice were smaller with reduced proliferation compared to wt nodules. By using an in vitro model of human HCC, we confirm that eIF6 depletion reduces the growth of HCC spheroids. We also tested three pharmacological inhibitors of eIF6 activity—eIFsixty-1, eIFsixty-4, and eIFsixty-6—and all three reduced eIF6 binding to 60S ribosomes and limited the growth of HCC spheroids. Thus, inhibition of eIF6 activity is feasible and limits HCC formation.

Cold Atmospheric Plasma Conveys Selectivity Against Hepatocellular Carcinoma Cells via Triggering EGFR(Tyr1068)-Mediated Autophagy

Hepatocellular carcinomas remain as a global health threat given its high mortality rate. We have previously identified the selectivity of cold atmospheric plasma (CAP) against multiple types of malignant tumors and proposed it as a promising onco-therapeutic strategy. Here, we investigated its roles in controlling hepatocellular carcinoma malignancy and one possible driving molecular mechanism. By focusing on post-translational modifications including acetylation, phosphorylation, and ubiquitination, we identified the crosstalk between EGFR acetylation and EGFR(Tyr1068) phosphorylation and their collective roles in determining LC3B ubiquitination and proposed the EGFR/p-JNK/BIRC6/LC3B axis in CAP-triggered autophagy. Our study not only demonstrated the selectivity of CAP against hepatocellular carcinoma malignancy and confirmed its roles as an onco-therapeutic tool but also opened the horizon of translating CAP into clinics toward a broader scope that included human longevity and anti-aging.

Discovery of a Novel Small-Molecule Inhibitor Disrupting TRBP-Dicer Interaction against Hepatocellular Carcinoma via the Modulation of microRNA Biogenesis

MicroRNAs (miRNAs) are key players in human hepatocellular carcinoma (HCC) tumorigenesis. Therefore, small molecules targeting components of miRNA biogenesis may provide new therapeutic means for HCC treatment. By a high-throughput screening and structural simplification, we identified a small molecule, CIB-3b, which suppresses the growth and metastasis of HCC in vitro and in vivo by modulating expression profiles of miRNAome and proteome in HCC cells. Mechanistically, CIB-3b physically binds to transactivation response (TAR) RNA-binding protein 2 (TRBP) and disrupts the TRBP-Dicer interaction, thereby altering the activity of Dicer and mature miRNA production. Structure-activity relationship study via the synthesis of 45 CIB-3b derivatives showed that some compounds exhibited a similar inhibitory effect on miRNA biogenesis to CIB-3b. These results support TRBP as a potential therapeutic target in HCC and warrant further development of CIB-3b along with its analogues as a novel therapeutic strategy for the treatment of HCC.

Targeting USP9X-AMPK Axis in ARID1A-Deficient Hepatocellular Carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is a highly heterogeneous solid tumor with high morbidity and mortality. AT-rich interaction domain 1A (ARID1A) accounts for up to 10% of mutations in liver cancer, however, its role in HCC remains controversial, and no targeted therapy has been established.

METHODS

The expression of ARID1A in clinical samples was examined by Western blot and immunohistochemical staining. ARID1A was knocked out by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) in HCC cell lines, and the effects of glucose deprivation on cell viability, proliferation, and apoptosis were measured. Mass spectrometry analysis was used to find ARID1A-interacting proteins, and the result was verified by co-immunoprecipitation and Glutathione S Transferase (GST) pull-down. The regulation of ARID1A target gene USP9X was investigated by chromatin immunoprecipitation, Glutathione S Transferase (GST) pull-down, luciferase reporter assay, and so forth. Finally, drug treatments were performed to explore the therapeutic potential of the agents targeting ARID1A-deficient HCC in vitro and in vivo.

RESULTS

Our study has shown that ARID1A loss protected cells from glucose deprivation-induced cell death. A mechanism study disclosed that AIRD1A recruited histone deacetylase 1 via its C-terminal region DUF3518 to the promoter of USP9X, resulting in down-regulation of USP9X and its target protein kinase AMP-activated catalytic subunit α2 (PRKAA2). ARID1A knockout and a 1989∗ truncation mutant in HCC abolished this effect, increased the levels of H3K9 and H3K27 acetylation at the USP9X promoter, and up-regulated the expression of USP9X and protein kinase AMP-activated catalytic subunit α2 (PRKAA2), which mediated the adaptation of tumor cells to glucose starvation. Compound C dramatically inhibited the growth of ARID1A-deficient tumors and prolongs the survival of tumor-bearing mice.

CONCLUSIONS

HCC patients with ARID1A mutation may benefit from synthetic lethal therapy targeting the ubiquitin-specific peptidase 9 X-linked (USP9X)-adenosine 5'-monophosphate-activated protein kinase (AMPK) axis.

Cellular origins of regenerating liver and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the predominant primary cancer arising from the liver and is one of the major causes of cancer-related mortality worldwide. The cellular origin of HCC has been a topic of great interest due to conflicting findings regarding whether it originates in hepatocytes, biliary cells, or facultative stem cells. These cell types all undergo changes during liver injury, and there is controversy about their contribution to regenerative responses in the liver. Most HCCs emerge in the setting of chronic liver injury from viral hepatitis, fatty liver disease, alcohol, and environmental exposures. The injuries are marked by liver parenchymal changes such as hepatocyte regenerative nodules, biliary duct cellular changes, expansion of myofibroblasts that cause fibrosis and cirrhosis, and inflammatory cell infiltration, all of which may contribute to carcinogenesis. Addressing the cellular origin of HCC is the key to identifying the earliest events that trigger it. Herein, we review data on the cells of origin in regenerating liver and HCC and the implications of these findings for prevention and treatment. We also review the origins of childhood liver cancer and other rare cancers of the liver.

Spatial Multiomics Analysis Reveals Only Minor Genetic and Epigenetic Changes in Human Liver Cancer Stem-Like Cells Compared With Other Tumor Parenchymal Cells

Cancer stem cells (CSCs) usually account for a very small tumor cell population but play pivotal roles in human cancer development and recurrence. A fundamental question in cancer biology is what genetic and epigenetic changes occur in CSCs. Here we show that the in-situ global levels of DNA cytosine modifications, including 5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC) and 5-formylcytosine (5fC), are similar between liver cancer stem-like (LCSL) cells and paratumor liver cells of liver cancer patients. We then developed a robust method combining immunohistochemistry, laser capture microdissection and genome sequencing with ultra-low-input cells (CIL-seq) to study the detailed genetic and DNA methylation changes in human LCSL cells. We first used clinical samples of mixed hepatocellular carcinoma-cholangiocarcinoma (HCC-CCA) with stem cell features to investigate human LCSL cells. The CIL-seq analysis of HCC-CCA and HCC patients showed that LCSL cells had strong spatial genetic and epigenetic heterogeneity. More interestingly, although the LCSL cells had some potential key changes in their genome, they had substantially fewer somatic single nucleotide variants (SNVs), copy number alterations (CNAs) and differentially methylated regions than other tumor parenchymal cells. The cluster analysis of SNVs, CNAs, DNA methylation patterns and spatial transcriptomes all clearly showed that the LCSL cells were clustered with the paratumor liver cells. Thus, spatial multiomics analysis showed that LCSL cells had only minor genetic and epigenetic changes compared with other tumor parenchymal cells. Targeting key changes in CSCs, not just changes in bulk tumor cells, should be more effective for human cancer therapy.

Identification of Subtypes of HCC Using Bioinformatics and the Hepatocyte Differentiation Model

The developmental signaling is closely associated with tumor aggressiveness. Subclassification of human hepatocellular carcinoma (HCC) from the developmental aspect may help understand the cellular origins of liver cancer, and further assist clinical practice. Here, we establish an in vitro hepatocyte differentiation model to induce human embryonic stem cells (hESCs) differentiation through progressive steps from uncommitted endoderm patterning to the multipotent liver progenitors, and finally differentiate into mature hepatocytes. The gene expression patterns and dynamic changes during hepatocyte differentiation could be monitored through RNA-sequencing of cells at different developmental stages. Hierarchical clustering analysis and topological data analysis could be used to generate and distinguish different subtypes of HCCs according to the gene expression signatures.

Growth differentiation factor 1-induced tumour plasticity provides a therapeutic window for immunotherapy in hepatocellular carcinoma

Tumour lineage plasticity is an emerging hallmark of aggressive tumours. Tumour cells usually hijack developmental signalling pathways to gain cellular plasticity and evade therapeutic targeting. In the present study, the secreted protein growth and differentiation factor 1 (GDF1) is found to be closely associated with poor tumour differentiation. Overexpression of GDF1 suppresses cell proliferation but strongly enhances tumour dissemination and metastasis. Ectopic expression of GDF1 can induce the dedifferentiation of hepatocellular carcinoma (HCC) cells into their ancestral lineages and reactivate a broad panel of cancer testis antigens (CTAs), which further stimulate the immunogenicity of HCC cells to immune-based therapies. Mechanistic studies reveal that GDF1 functions through the Activin receptor-like kinase 7 (ALK7)-Mothers against decapentaplegic homolog 2/3 (SMAD2/3) signalling cascade and suppresses the epigenetic regulator Lysine specific demethylase 1 (LSD1) to boost CTA expression. GDF1-induced tumour lineage plasticity might be an Achilles heel for HCC immunotherapy. Inhibition of LSD1 based on GDF1 biomarker prescreening might widen the therapeutic window for immune checkpoint inhibitors in the clinic.

Poorly differentiated hepatocellular carcinoma (HCC) is an aggressive disease with poor prognosis. Here the authors show that GDF1, a member of the TGF-β superfamily, is highly expressed in high-grade poorly differentiated HCC and is associated with tumor plasticity, and that GDF1-induced reexpression of cancer testis antigens could render tumors sensitive to immune checkpoint inhibition.

Expression and Prognostic Role of E2F2 in Hepatocellular Carcinoma

Introduction

Hepatocellular carcinoma (HCC) is a common clinical malignancy. Recent studies reported that E2F transcription factor 2 (E2F2) plays a significant role in tumor progression. However, its expression and biological function in HCC are still unclear. Therefore, we explored the relationship between E2F2 expression and tumor progression in HCC.

Methods

In this study, we utilized some online tools to explore the E2F2 expression in pan-carcinoma and HCC. The association of E2F2 expression with the clinical characteristics and prognosis of HCC was further studied. In addition, we explored the co-expressed genes of E2F2 and mined the positively/negatively corrected significant genes and excavated the possible functions. Meanwhile, the hub gene set was constructed based on protein-protein interaction (PPI) network, and the relationship between E2F2 and immunity was discovered.

Results

We observed that the expression level of E2F2 was generally upregulated in HCC. However, E2F2 expression was not significantly different between HCC and normal tissues in regard to the disease stage 4. Furthermore, we also observed the poor prognosis in patients with high E2F2 expression. The co-expressed genes of E2F2 were identified and further detected. Thereafter, we identified the positively/negatively corrected significant genes and constructed the hub gene network of E2F2 based on PPI network. We also found that E2F2 expression was positively correlated with the infiltration levels of CD4+ T, CD8+ T cells, macrophages, neutrophils, and dendritic cells.

Conclusion

Our findings suggested that E2F2 could be a potential prognostic factor for HCC, which could provide a therapeutic target for the molecular treatment of HCC.

In Vivo and In Vitro Models of Hepatocellular Carcinoma: Current Strategies for Translational Modeling

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the third leading cause of cancer-related death globally. HCC is a complex multistep disease and usually emerges in the setting of chronic liver diseases. The molecular pathogenesis of HCC varies according to the etiology, mainly caused by chronic hepatitis B and C virus infections, chronic alcohol consumption, aflatoxin-contaminated food, and non-alcoholic fatty liver disease associated with metabolic syndrome or diabetes mellitus. The establishment of HCC models has become essential for both basic and translational research to improve our understanding of the pathophysiology and unravel new molecular drivers of this disease. The ideal model should recapitulate key events observed during hepatocarcinogenesis and HCC progression in view of establishing effective diagnostic and therapeutic strategies to be translated into clinical practice. Despite considerable efforts currently devoted to liver cancer research, only a few anti-HCC drugs are available, and patient prognosis and survival are still poor. The present paper provides a state-of-the-art overview of in vivo and in vitro models used for translational modeling of HCC with a specific focus on their key molecular hallmarks.

Surgery After Conversion Therapy With PD-1 Inhibitors Plus Tyrosine Kinase Inhibitors Are Effective and Safe for Advanced Hepatocellular Carcinoma: A Pilot Study of Ten Patients

Background and Aims

Immunotherapy with PD-1 inhibitors combined with tyrosine kinase inhibitors (TKIs) has been proven to be effective against advanced hepatocellular carcinoma (HCC). The aim of this study was to identify the feasibility and safety of subsequent salvage surgery after this combination therapy.

Methods and Patients

A retrospective analysis was performed on patients with primary HCC with major vascular invasion between 2018 and 2019. All cases were treated with a combination of a PD-1 inhibitor and TKI agents and subsequent surgery.

Results

A total of 10 HCC cases with major vascular invasion met the successful conversion criteria after the combination therapy, and eight patients underwent subsequent salvage surgery after both radiology and 3D quantitative oncological assessment. Partial response (PR) was recorded in 7 of 10 patients and complete response (CR) in 3 of 10 patients before salvage surgery. Salvage surgery included right hepatectomy, left hepatectomy, and anatomic segmental hepatectomy. The mean intraoperative blood loss was 1,650 ml (50–3,000 ml). No complications beyond Clavien–Dindo level III or postoperative mortality were observed. The viable tumor cell rate of the PR cases (modified response evaluation criteria in solid tumors, mRECIST) varied from 1.5% to 100%, and only one patient had pathology-proven pathological complete response (pCR). The postoperative median follow-up time was 19.7 months (9.1–24.9 months). The 12-month recurrence-free survival rate of all cases who underwent salvage surgery was 75%.

Conclusion

Salvage surgery was effective and safe after conversion therapy with PD-1 inhibitors plus TKIs and may increase the long-term oncological benefit for patients with unresectable HCC.