Adjuvant and neoadjuvant immunotherapies in hepatocellular carcinoma.

Liver cancer, specifically hepatocellular carcinoma (HCC), is the sixth most common cancer and the third leading cause of cancer mortality worldwide. The development of effective systemic therapies, particularly those involving immune-checkpoint inhibitors (ICIs), has substantially improved the outcomes of patients with advanced-stage HCC. Approximately 30% of patients are diagnosed with early stage disease and currently receive potentially curative therapies, such as resection, liver transplantation or local ablation, which result in median overall survival durations beyond 60 months. Nonetheless, up to 70% of these patients will have disease recurrence within 5 years of resection or local ablation. To date, the results of randomized clinical trials testing adjuvant therapy in patients with HCC have been negative. This major unmet need has been addressed with the IMbrave 050 trial, demonstrating a recurrence-free survival benefit in patients with a high risk of relapse after resection or local ablation who received adjuvant atezolizumab plus bevacizumab. In parallel, studies testing neoadjuvant ICIs alone or in combination in patients with early stage disease have also reported efficacy. In this Review, we provide a comprehensive overview of the current approaches to manage patients with early stage HCC. We also describe the tumour immune microenvironment and the mechanisms of action of ICIs and cancer vaccines in this setting. Finally, we summarize the available evidence from phase II/III trials of neoadjuvant and adjuvant approaches and discuss emerging clinical trials, identification of biomarkers and clinical trial design considerations for future studies.

Tcf20 deficiency is associated with increased liver fibrogenesis and alterations in mitochondrial metabolism in mice and humans.

BACKGROUND & AIMS: Transcription co-activator factor 20 (TCF20) is a regulator of transcription factors involved in extracellular matrix remodelling. In addition, TCF20 genomic variants in humans have been associated with impaired intellectual disability. Therefore, we hypothesized that TCF20 has several functions beyond those described in neurogenesis, including the regulation of fibrogenesis. METHODS: Tcf20 knock-out (Tcf20-/- ) and Tcf20 heterozygous mice were generated by homologous recombination. TCF20 gene genotyping and expression was assessed in patients with pathogenic variants in the TCF20 gene. Neural development was investigated by immufluorescense. Mitochondrial metabolic activity was evaluated with the Seahorse analyser. The proteome analysis was carried out by gas chromatography mass-spectrometry. RESULTS: Characterization of Tcf20-/- newborn mice showed impaired neural development and death after birth. In contrast, heterozygous mice were viable but showed higher CCl4 -induced liver fibrosis and a differential expression of genes involved in extracellular matrix homeostasis compared to wild-type mice, along with abnormal behavioural patterns compatible with autism-like phenotypes. Tcf20-/- embryonic livers and mouse embryonic fibroblast (MEF) cells revealed differential expression of structural proteins involved in the mitochondrial oxidative phosphorylation chain, increased rates of mitochondrial metabolic activity and alterations in metabolites of the citric acid cycle. These results parallel to those found in patients with TCF20 pathogenic variants, including alterations of the fibrosis scores (ELF and APRI) and the elevation of succinate concentration in plasma. CONCLUSIONS: We demonstrated a new role of Tcf20 in fibrogenesis and mitochondria metabolism in mice and showed the association of TCF20 deficiency with fibrosis and metabolic biomarkers in humans.

Identification of IGF2 as Genomic Driver and Actionable Therapeutic Target in Hepatoblastoma.

Management of hepatoblastoma (HB), the most frequent pediatric liver cancer, is based on surgical resection and perioperative chemotherapy regimens. In this study, we aimed to identify actionable targets in HB and assess the efficacy of molecular therapies in preclinical models of HB. Paired tumor and adjacent tissues from 31 HBs and a validation set of 50 HBs were analyzed using RNA-seq, SNP, and methylation arrays. IGF2 overexpression was identified as the top targetable HB driver, present in 71% of HBs (22/31). IGF2high tumors displayed progenitor cell features and shorter recurrence-free survival. IGF2 overexpression was associated in 91% of cases with fetal promoter hypomethylation, ICR1 deregulation, 11p15.5 loss of heterozygosity or miR483-5p overexpression. The antitumor effect of xentuzumab (a monoclonal antibody targeting IGF1/2) alone or in combination with the conventional therapeutic agent cisplatin was assessed in HB cell lines, in PDX-derived HB organoids and in a xenograft HB murine model. The combination of xentuzumab with cisplatin showed strong synergistic antitumor effects in organoids and in IGF2high cell lines. In mice (n = 55), the combination induced a significant decrease in tumor volume and improved survival compared with cisplatin alone. These results suggest that IGF2 is an HB actionable driver and that, in preclinical models of HB, the combination of IGF1/2 inhibition with cisplatin induces superior antitumor effects than cisplatin monotherapy. Overall, our study provides a rationale for testing IGF2 inhibitors in combination with cisplatin in HB patients with IGF2 overexpression.

Inflamed and non-inflamed classes of HCC: a revised immunogenomic classification.

OBJECTIVE: We previously reported a characterisation of the hepatocellular carcinoma (HCC) immune contexture and described an immune-specific class. We now aim to further delineate the immunogenomic classification of HCC to incorporate features that explain responses/resistance to immunotherapy. DESIGN: We performed RNA and whole-exome sequencing, T-cell receptor (TCR)-sequencing, multiplex immunofluorescence and immunohistochemistry in a novel cohort of 240 HCC patients and validated our results in other cohorts comprising 660 patients. RESULTS: Our integrative analysis led to define: (1) the inflamed class of HCC (37%), which includes the previously reported immune subclass (22%) and a new immune-like subclass (15%) with high interferon signalling, cytolytic activity, expression of immune-effector cytokines and a more diverse T-cell repertoire. A 20-gene signature was able to capture ~90% of these tumours and is associated with response to immunotherapy. Proteins identified in liquid biopsies recapitulated the inflamed class with an area under the ROC curve (AUC) of 0.91; (2) The intermediate class, enriched in TP53 mutations (49% vs 29%, p=0.035), and chromosomal losses involving immune-related genes and; (3) the excluded class, enriched in CTNNB1 mutations (93% vs 27%, p<0.001) and PTK2 overexpression due to gene amplification and promoter hypomethylation. CTNNB1 mutations outside the excluded class led to weak activation of the Wnt-ßcatenin pathway or occurred in HCCs dominated by high interferon signalling and type I antigen presenting genes. CONCLUSION: We have characterised the immunogenomic contexture of HCC and defined inflamed and non-inflamed tumours. Two distinct CTNNB1 patterns associated with a differential role in immune evasion are described. These features may help predict immune response in HCC.

CXCR2 inhibition enables NASH-HCC immunotherapy.

OBJECTIVE: Hepatocellular carcinoma (HCC) is increasingly associated with non-alcoholic steatohepatitis (NASH). HCC immunotherapy offers great promise; however, recent data suggests NASH-HCC may be less sensitive to conventional immune checkpoint inhibition (ICI). We hypothesised that targeting neutrophils using a CXCR2 small molecule inhibitor may sensitise NASH-HCC to ICI therapy. DESIGN: Neutrophil infiltration was characterised in human HCC and mouse models of HCC. Late-stage intervention with anti-PD1 and/or a CXCR2 inhibitor was performed in murine models of NASH-HCC. The tumour immune microenvironment was characterised by imaging mass cytometry, RNA-seq and flow cytometry. RESULTS: Neutrophils expressing CXCR2, a receptor crucial to neutrophil recruitment in acute-injury, are highly represented in human NASH-HCC. In models of NASH-HCC lacking response to ICI, the combination of a CXCR2 antagonist with anti-PD1 suppressed tumour burden and extended survival. Combination therapy increased intratumoural XCR1+ dendritic cell activation and CD8+ T cell numbers which are associated with anti-tumoural immunity, this was confirmed by loss of therapeutic effect on genetic impairment of myeloid cell recruitment, neutralisation of the XCR1-ligand XCL1 or depletion of CD8+ T cells. Therapeutic benefit was accompanied by an unexpected increase in tumour-associated neutrophils (TANs) which switched from a protumour to anti-tumour progenitor-like neutrophil phenotype. Reprogrammed TANs were found in direct contact with CD8+ T cells in clusters that were enriched for the cytotoxic anti-tumoural protease granzyme B. Neutrophil reprogramming was not observed in the circulation indicative of the combination therapy selectively influencing TANs. CONCLUSION: CXCR2-inhibition induces reprogramming of the tumour immune microenvironment that promotes ICI in NASH-HCC.

Molecular pathogenesis and systemic therapies for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) remains one of the most prevalent and deadliest cancers. The poor outcome associated with HCC is dramatically changing due to the advent of effective systemic therapies. Here we discuss the molecular pathogenesis of HCC, molecular classes and determinants of heterogeneity. In addition, effective single-agent and combination systemic therapies involving immunotherapies as standard of care are analyzed. Finally, we propose a flowchart of sequential therapies, explore mechanisms of resistance and address the need for predictive biomarkers.

Cabozantinib Enhances Anti-PD1 Activity and Elicits a Neutrophil-Based Immune Response in Hepatocellular Carcinoma.

PURPOSE: Immune checkpoint inhibitors combined with antiangiogenic agents produce benefits in the treatment of advanced hepatocellular carcinoma (HCC). We investigated the efficacy and immunomodulatory activity of cabozantinib alone and combined with anti-PD1 in experimental models of HCC, and explored the potential target population that might benefit from this combination. EXPERIMENTAL DESIGN: C57BL/6J mice bearing subcutaneous Hepa1-6 or Hep53.4 tumors received cabozantinib, anti-PD1, their combination, or placebo. Tumor and blood samples were analyzed by flow cytometry, IHC, transcriptome, and cytokine profiling. Cabozantinib-related effects were validated in a colorectal cancer patient-derived xenograft model. Transcriptomic data from three human HCC cohorts (cohort 1: n = 167, cohort 2: n = 57, The Cancer Genome Atlas: n = 319) were used to cluster patients according to neutrophil features, and assess their impact on survival. RESULTS: The combination of cabozantinib and anti-PD1 showed increased antitumor efficacy compared with monotherapy and placebo (P < 0.05). Cabozantinib alone significantly increased neutrophil infiltration and reduced intratumor CD8+PD1+ T-cell proportions, while the combination with anti-PD1 further stimulated both effects and significantly decreased regulatory T cell (Treg) infiltration (all P < 0.05). In blood, cabozantinib and especially combination increased the proportions of overall T cells (P < 0.01) and memory/effector T cells (P < 0.05), while lowering the neutrophil-to-lymphocyte ratio (P < 0.001 for combination). Unsupervised clustering of human HCCs revealed that high tumor enrichment in neutrophil features observed with the treatment combination was linked to less aggressive tumors with more differentiated and less proliferative phenotypes. CONCLUSIONS: Cabozantinib in combination with anti-PD1 enhanced antitumor immunity by bringing together innate neutrophil-driven and adaptive immune responses, a mechanism of action which favors this approach for HCC treatment.

Molecular characterisation of hepatocellular carcinoma in patients with non-alcoholic steatohepatitis.

BACKGROUND AND AIMS: Non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) is increasing globally, but its molecular features are not well defined. We aimed to identify unique molecular traits characterising NASH-HCC compared to other HCC aetiologies. METHODS: We collected 80 NASH-HCC and 125 NASH samples from 5 institutions. Expression array (n = 53 NASH-HCC; n = 74 NASH) and whole exome sequencing (n = 52 NASH-HCC) data were compared to HCCs of other aetiologies (n = 184). Three NASH-HCC mouse models were analysed by RNA-seq/expression-array (n = 20). Activin A receptor type 2A (ACVR2A) was silenced in HCC cells and proliferation assessed by colorimetric and colony formation assays. RESULTS: Mutational profiling of NASH-HCC tumours revealed TERT promoter (56%), CTNNB1 (28%), TP53 (18%) and ACVR2A (10%) as the most frequently mutated genes. ACVR2A mutation rates were higher in NASH-HCC than in other HCC aetiologies (10% vs. 3%, p <0.05). In vitro, ACVR2A silencing prompted a significant increase in cell proliferation in HCC cells. We identified a novel mutational signature (MutSig-NASH-HCC) significantly associated with NASH-HCC (16% vs. 2% in viral/alcohol-HCC, p = 0.03). Tumour mutational burden was higher in non-cirrhotic than in cirrhotic NASH-HCCs (1.45 vs. 0.94 mutations/megabase; p <0.0017). Compared to other aetiologies of HCC, NASH-HCCs were enriched in bile and fatty acid signalling, oxidative stress and inflammation, and presented a higher fraction of Wnt/TGF-ß proliferation subclass tumours (42% vs. 26%, p = 0.01) and a lower prevalence of the CTNNB1 subclass. Compared to other aetiologies, NASH-HCC showed a significantly higher prevalence of an immunosuppressive cancer field. In 3 murine models of NASH-HCC, key features of human NASH-HCC were preserved. CONCLUSIONS: NASH-HCCs display unique molecular features including higher rates of ACVR2A mutations and the presence of a newly identified mutational signature. LAY SUMMARY: The prevalence of hepatocellular carcinoma (HCC) associated with non-alcoholic steatohepatitis (NASH) is increasing globally, but its molecular traits are not well characterised. In this study, we uncovered higher rates of ACVR2A mutations (10%) - a potential tumour suppressor - and the presence of a novel mutational signature that characterises NASH-related HCC.

NASH limits anti-tumour surveillance in immunotherapy-treated HCC.

Hepatocellular carcinoma (HCC) can have viral or non-viral causes1-5. Non-alcoholic steatohepatitis (NASH) is an important driver of HCC. Immunotherapy has been approved for treating HCC, but biomarker-based stratification of patients for optimal response to therapy is an unmet need6,7. Here we report the progressive accumulation of exhausted, unconventionally activated CD8+PD1+ T cells in NASH-affected livers. In preclinical models of NASH-induced HCC, therapeutic immunotherapy targeted at programmed death-1 (PD1) expanded activated CD8+PD1+ T cells within tumours but did not lead to tumour regression, which indicates that tumour immune surveillance was impaired. When given prophylactically, anti-PD1 treatment led to an increase in the incidence of NASH-HCC and in the number and size of tumour nodules, which correlated with increased hepatic CD8+PD1+CXCR6+, TOX+, and TNF+ T cells. The increase in HCC triggered by anti-PD1 treatment was prevented by depletion of CD8+ T cells or TNF neutralization, suggesting that CD8+ T cells help to induce NASH-HCC, rather than invigorating or executing immune surveillance. We found similar phenotypic and functional profiles in hepatic CD8+PD1+ T cells from humans with NAFLD or NASH. A meta-analysis of three randomized phase III clinical trials that tested inhibitors of PDL1 (programmed death-ligand 1) or PD1 in more than 1,600 patients with advanced HCC revealed that immune therapy did not improve survival in patients with non-viral HCC. In two additional cohorts, patients with NASH-driven HCC who received anti-PD1 or anti-PDL1 treatment showed reduced overall survival compared to patients with other aetiologies. Collectively, these data show that non-viral HCC, and particularly NASH-HCC, might be less responsive to immunotherapy, probably owing to NASH-related aberrant T cell activation causing tissue damage that leads to impaired immune surveillance. Our data provide a rationale for stratification of patients with HCC according to underlying aetiology in studies of immunotherapy as a primary or adjuvant treatment.

Liver Injury Increases the Incidence of HCC following AAV Gene Therapy in Mice.

Adeno-associated virus (AAV) integrates into host genomes at low frequency, but when integration occurs in oncogenic hotspots it can cause hepatocellular carcinoma (HCC). Given the possibility of recombinant AAV (rAAV) integration leading to HCC, common causes of liver inflammation like non-alcoholic fatty liver disease (NAFLD) may increase the risk of rAAV-induced HCC. A rAAV targeting the oncogenic mouse Rian locus was used, and as expected led to HCC in all mice infected as neonates, likely due to growth-related hepatocyte proliferation in young mice. Mice infected with rAAV as adults did not develop HCC unless they were fed a diet leading to NAFLD, with increased inflammation and hepatocyte proliferation. Female mice were less susceptible to rAAV-induced HCC, and male mice with NAFLD treated with estrogen exhibited less inflammation and immune exhaustion associated with oncogenesis compared to those without estrogen. Adult NAFLD mice infected with a non-targeted control rAAV also developed HCC, though only half as frequently as those exposed to the Rian targeted rAAV. This study shows that adult mice exposed to rAAV gene therapy in the context of chronic liver disease developed HCC at high frequency, and thus warrants further study in humans given the high prevalence of NAFLD in the population.

Copy-Number Alteration Burden Differentially Impacts Immune Profiles and Molecular Features of Hepatocellular Carcinoma.

PURPOSE: Chromosomal instability is a hallmark of cancer that results in broad and focal copy-number alterations (CNAs), two events associated with distinct molecular, immunologic, and clinical features. In hepatocellular carcinoma (HCC), the role of CNAs has not been thoroughly assessed. Thus, we dissected the impact of CNA burdens on HCC molecular and immune features. EXPERIMENTAL DESIGN: We analyzed SNP array data from 452 paired tumor/adjacent resected HCCs and 25 dysplastic nodules. For each sample, broad and focal CNA burdens were quantified using CNApp, and the resulting broad scores (BS) and focal scores (FS) were correlated with transcriptomic, mutational, and methylation profiles, tumor immune composition, and clinicopathologic data. RESULTS: HCCs with low broad CNA burdens (defined as BS ≤ 4; 17%) presented high inflammation, active infiltrate signaling, high cytolytic activity, and enrichment of the "HCC immune class" and gene signatures related to antigen presentation. Conversely, tumors with chromosomal instability (high broad CNA loads, BS ≥ 11; 40%), displayed immune-excluded traits and were linked to proliferation, TP53 dysfunction, and DNA repair. Candidate determinants of the low cytotoxicity and immune exclusion features of high-BS tumors included alterations in antigen-presenting machinery (i.e., HLA), widespread hypomethylation, and decreased rates of observed/expected neoantigenic mutations. High FSs were independent of tumor immune features, but were related to proliferation, TP53 dysfunction, and progenitor cell traits. CONCLUSIONS: HCCs with high chromosomal instability exhibit features of immune exclusion, whereas tumors displaying low burdens of broad CNAs present an immune active profile. These CNA scores can be tested to predict response to immunotherapies.

Molecular classification and therapeutic targets in extrahepatic cholangiocarcinoma.

BACKGROUND & AIMS: Cholangiocarcinoma (CCA), a deadly malignancy of the bile ducts, can be classified based on its anatomical location into either intrahepatic (iCCA) or extrahepatic (eCCA), each with different pathogenesis and clinical management. There is limited understanding of the molecular landscape of eCCA and no targeted therapy with clinical efficacy has been approved. We aimed to provide a molecular classification of eCCA and identify potential targets for molecular therapies. METHODS: An integrative genomic analysis of an international multicenter cohort of 189 eCCA cases was conducted. Genomic analysis included whole-genome expression, targeted DNA-sequencing and immunohistochemistry. Molecular findings were validated in an external set of 181 biliary tract tumors from the ICGC. RESULTS: KRAS (36.7%), TP53 (34.7%), ARID1A (14%) and SMAD4 (10.7%) were the most prevalent mutations, with ∼25% of tumors having a putative actionable genomic alteration according to OncoKB. Transcriptome-based unsupervised clustering helped us define 4 molecular classes of eCCA. Tumors classified within the Metabolic class (19%) showed a hepatocyte-like phenotype with activation of the transcription factor HNF4A and enrichment in gene signatures related to bile acid metabolism. The Proliferation class (23%), more common in patients with distal CCA, was characterized by enrichment of MYC targets, ERBB2 mutations/amplifications and activation of mTOR signaling. The Mesenchymal class (47%) was defined by signatures of epithelial-mesenchymal transition, aberrant TGFß signaling and poor overall survival. Finally, tumors in the Immune class (11%) had a higher lymphocyte infiltration, overexpression of PD-1/PD-L1 and molecular features associated with a better response to immune checkpoint inhibitors. CONCLUSION: An integrative molecular characterization identified distinct subclasses of eCCA. Genomic traits of each class provide the rationale for exploring patient stratification and novel therapeutic approaches. LAY SUMMARY: Targeted therapies have not been approved for the treatment of extrahepatic cholangiocarcinoma. We performed a multi-platform molecular characterization of this tumor in a cohort of 189 patients. These analyses revealed 4 novel transcriptome-based molecular classes of extrahepatic cholangiocarcinoma and identified ∼25% of tumors with actionable genomic alterations, which has potential prognostic and therapeutic implications.

R-spondin 2 Drives Liver Tumor Development in a Yes-Associated Protein-Dependent Manner.

Each year, more than 25,000 people succumb to liver cancer in the United States, and this neoplasm represents the second cause of cancer-related death globally. R-spondins (RSPOs) are secreted regulators of Wnt signaling that function in development and promote tissue stem cell renewal. In cancer, RSPOs 2 and 3 are oncogenes first identified by insertional mutagenesis screens in tumors induced by mouse mammary tumor virus and by transposon mutagenesis in the colonic epithelium of rodents. RSPO2 has been reported to be activated by chromosomal rearrangements in colorectal cancer and overexpressed in a subset of hepatocellular carcinoma. Using human liver tumor gene expression data, we first discovered that a subset of liver cancers were characterized by high levels of RSPO2 in contrast to low levels in adjacent nontumor tissue. To determine if RSPOs are capable of inducing liver tumors, we used an in vivo model from which we found that overexpression of RSPO2 in the liver promoted Wnt signaling, hepatomegaly, and enhanced liver tumor formation when combined with loss of transformation-related protein 53 (Trp53). Moreover, the Hippo/yes-associated protein (Yap) pathway has been implicated in many human cancers, influencing cell survival. Histologic and gene expression studies showed activation of Wnt/ß-catenin and Hippo/Yap pathways following RSPO2 overexpression. We demonstrate that knockdown of Yap1 leads to reduced tumor penetrance following RSPO2 overexpression in the context of loss of Trp53. Conclusion: RSPO2 overexpression leads to tumor formation in the mouse liver in a Hippo/Yap-dependent manner. Overall, our results suggest a role for Yap in the initiation and progression of liver tumors and uncover a novel pathway activated in RSPO2-induced malignancies. We show that RSPO2 promotes liver tumor formation in vivo and in vitro and that RSPO2's oncogenic activity requires Hippo/Yap activation in hepatocytes. Both RSPO2 and YAP1 are suggested to represent novel druggable targets in Wnt-driven tumors of the liver.

An Immune Gene Expression Signature Associated With Development of Human Hepatocellular Carcinoma Identifies Mice That Respond to Chemopreventive Agents.

BACKGROUND & AIMS: Cirrhosis and chronic inflammation precede development of hepatocellular carcinoma (HCC) in approximately 80% of cases. We investigated immune-related gene expression patterns in liver tissues surrounding early-stage HCCs and chemopreventive agents that might alter these patterns to prevent liver tumorigenesis. METHODS: We analyzed gene expression profiles of nontumor liver tissues from 392 patients with early-stage HCC (training set, N = 167 and validation set, N = 225) and liver tissue from patients with cirrhosis without HCC (N = 216, controls) to identify changes in expression of genes that regulate the immune response that could contribute to hepatocarcinogenesis. We defined 172 genes as markers for this deregulated immune response, which we called the immune-mediated cancer field (ICF). We analyzed the expression data of liver tissues from 216 patients with cirrhosis without HCC and investigated the association between this gene expression signature and development of HCC and outcomes of patients (median follow-up, 10 years). Human liver tissues were also analyzed by histology. C57BL/6J mice were given a single injection of diethylnitrosamine (DEN) followed by weekly doses of carbon tetrachloride to induce liver fibrosis and tumorigenesis. Mice were then orally given the multiple tyrosine inhibitor nintedanib or vehicle (controls); liver tissues were collected and histology, transcriptome, and protein analyses were performed. We also analyzed transcriptomes of liver tissues collected from mice on a choline-deficient high-fat diet, which developed chronic liver inflammation and tumors, orally given aspirin and clopidogrel or the anti-inflammatory agent sulindac vs mice on a chow (control) diet. RESULTS: We found the ICF gene expression pattern in 50% of liver tissues from patients with cirrhosis without HCC and in 60% of nontumor liver tissues from patients with early-stage HCC. The liver tissues with the ICF gene expression pattern had 3 different features: increased numbers of effector T cells; increased expression of genes that suppress the immune response and activation of transforming growth factor ß signaling; or expression of genes that promote inflammation and activation of interferon gamma signaling. Patients with cirrhosis and liver tissues with the immunosuppressive profile (10% of cases) had a higher risk of HCC (hazard ratio, 2.41; 95% confidence interval, 1.21-4.80). Mice with chemically induced fibrosis or diet-induced steatohepatitis given nintedanib or aspirin and clopidogrel down-regulated the ICF gene expression pattern in liver and developed fewer and smaller tumors than mice given vehicle. CONCLUSIONS: We identified an immune-related gene expression pattern in liver tissues of patients with early-stage HCC, called the ICF, that is associated with risk of HCC development in patients with cirrhosis. Administration of nintedanib or aspirin and clopidogrel to mice with chronic liver inflammation caused loss of this gene expression pattern and development of fewer and smaller liver tumors. Agents that alter immune regulatory gene expression patterns associated with carcinogenesis might be tested as chemopreventive agents in patients with cirrhosis.

Molecular portrait of high alpha-fetoprotein in hepatocellular carcinoma: implications for biomarker-driven clinical trials.

The clinical utility of serum alpha-fetoprotein (AFP) in patients with hepatocellular carcinoma (HCC) is widely recognised. However, a clear understanding of the mechanisms of AFP overexpression and the molecular traits of patients with AFP-high tumours are not known. We assessed transcriptome data, whole-exome sequencing data and DNA methylome profiling of 520 HCC patients from two independent cohorts to identify distinct molecular traits of patients with AFP-high tumours (serum concentration > 400 ng/ml), which represents an accepted prognostic cut-off and a predictor of response to ramucirumab. Those AFP-high tumours (18% of resected cases) were characterised by significantly lower AFP promoter methylation (p < 0.001), significant enrichment of progenitor-cell features (CK19, EPCAM), higher incidence of BAP1 oncogene mutations (8.5% vs 1.6%) and lower mutational rates of CTNNB1 (14% vs 30%). Specifically, AFP-high tumours displayed significant activation of VEGF signalling (p < 0.001), which might provide the rationale for the reported benefit of ramucirumab in this subgroup of patients.

Immune Exclusion-Wnt/CTNNB1 Class Predicts Resistance to Immunotherapies in HCC.

Next-generation sequencing has provided information on actionable targets and biomarkers of response in oncology. In hepatocellular carcinoma (HCC), Wnt/CTNNB1 mutations characterize the immune-excluded class (cold tumors) and might represent the biomarkers predicting resistance to immune checkpoint inhibitors. Large-scale validation of these data is needed to customize immunotherapy in advanced HCC.See related article by Harding et al., p. 2116.

Molecular predictors of prevention of recurrence in HCC with sorafenib as adjuvant treatment and prognostic factors in the phase 3 STORM trial.

OBJECTIVE: Sorafenib is the standard systemic therapy for advanced hepatocellular carcinoma (HCC). Survival benefits of resection/local ablation for early HCC are compromised by 70% 5-year recurrence rates. The phase 3 STORM trial comparing sorafenib with placebo as adjuvant treatment did not achieve its primary endpoint of improving recurrence-free survival (RFS). The biomarker companion study BIOSTORM aims to define (A) predictors of recurrence prevention with sorafenib and (B) prognostic factors with B level of evidence. DESIGN: Tumour tissue from 188 patients randomised to receive sorafenib (83) or placebo (105) in the STORM trial was collected. Analyses included gene expression profiling, targeted exome sequencing (19 known oncodrivers), immunohistochemistry (pERK, pVEGFR2, Ki67), fluorescence in situ hybridisation (VEGFA) and immunome. A gene signature capturing improved RFS in sorafenib-treated patients was generated. All 70 RFS events were recurrences, thus time to recurrence equalled RFS. Predictive and prognostic value was assessed using Cox regression models and interaction test. RESULTS: BIOSTORM recapitulates clinicopathological characteristics of STORM. None of the biomarkers tested (related to angiogenesis and proliferation) or previously proposed gene signatures, or mutations predicted sorafenib benefit or recurrence. A newly generated 146-gene signature identifying 30% of patients captured benefit to sorafenib in terms of RFS (p of interaction=0.04). These sorafenib RFS responders were significantly enriched in CD4+ T, B and cytolytic natural killer cells, and lacked activated adaptive immune components. Hepatocytic pERK (HR=2.41; p=0.012) and microvascular invasion (HR=2.09; p=0.017) were independent prognostic factors. CONCLUSION: In BIOSTORM, only hepatocytic pERK and microvascular invasion predicted poor RFS. No mutation, gene amplification or previously proposed gene signatures predicted sorafenib benefit. A newly generated multigene signature associated with improved RFS on sorafenib warrants further validation. TRIAL REGISTRATION NUMBER: NCT00692770.

IGF2 Is Up-regulated by Epigenetic Mechanisms in Hepatocellular Carcinomas and Is an Actionable Oncogene Product in Experimental Models.

BACKGROUND & AIMS: Effective treatments are urgently needed for hepatocellular carcinoma (HCC), which is usually diagnosed at advanced stages. Signaling via the insulin-like growth factor (IGF) pathway is aberrantly activated in HCC by IGF2 overexpression. We aimed to elucidate the mechanism of IGF2 overexpression and its oncogenic activities and evaluate the anti-tumor effects of reducing IGF2 signaling. METHODS: We obtained 228 HCC samples from patients who underwent liver resection, 168 paired non-tumor adjacent cirrhotic liver samples, and 10 non-tumor liver tissues from patients undergoing resection for hepatic hemangioma. We analyzed gene expression, microRNA, and DNA methylation profiles for all samples, focusing on genes in the IGF signaling pathway. IGF2 was expressed in SNU449 and PLC5 HCC cells and knocked down with small hairpin RNAs in Hep3B and Huh7 cell lines. We analyzed these cells for proliferation, apoptosis, migration, and colony formation. We performed studies in mice engineered to express Myc and Akt1 in liver, which develop liver tumors, with or without hepatic expression of Igf2. Mice with xenograft tumors grown from HCC cells were given a monoclonal antibody against IGF1 and IGF2 (xentuzumab), along with sorafenib; tumor growth was measured and tissues were analyzed by immunohistochemistry and immunoblots. RESULTS: Levels of IGF2 messenger RNA and protein were increased >20-fold in 15% of human HCC tissues compared with non-tumor liver tissues. Methylation at the fetal promoters of IGF2 was reduced in the HCC samples and cell lines that overexpressed IGF2, compared with those that did not overexpress this gene, and non-tumor tissues. Tumors that overexpressed IGF2 had gene expression patterns significantly associated with hepatic progenitor cell features, stellate cell activation, NOTCH signaling, and an aggressive phenotype (P < .0001). In mice engineered to express Myc and Akt1 in liver, co-expression of Igf2 accelerated formation of liver tumors, compared to mice with livers expressing only Myc and Akt1, and shortened survival times (P = .02). The antibody xentuzumab blocked phosphorylation of IGF1 receptor in HCC cell lines and reduced their proliferation and colony formation. In mice with xenograft tumors, injection of xentuzumab, with or without sorafenib, slowed tumor growth and increased survival times compared to vehicle or sorafenib alone. Xentuzumab inhibited phosphorylation of IGF1 receptor and AKT and reduced decreased tumor vascularization compared with vehicle. CONCLUSIONS: A large proportion of HCC samples were found to overexpress IGF2, via demethylation of its fetal promoter. Overexpression of IGF2 accelerates formation of liver tumors in mice with hepatic expression of MYC and AKT1, via activation of IGF1 receptor signaling. An antibody against IGF1 and IGF2 slows growth of xenograft tumors and increases survival of these mice.

Exome sequencing of hepatocellular carcinomas identifies new mutational signatures and potential therapeutic targets.

Genomic analyses promise to improve tumor characterization to optimize personalized treatment for patients with hepatocellular carcinoma (HCC). Exome sequencing analysis of 243 liver tumors identified mutational signatures associated with specific risk factors, mainly combined alcohol and tobacco consumption and exposure to aflatoxin B1. We identified 161 putative driver genes associated with 11 recurrently altered pathways. Associations of mutations defined 3 groups of genes related to risk factors and centered on CTNNB1 (alcohol), TP53 (hepatitis B virus, HBV) and AXIN1. Analyses according to tumor stage progression identified TERT promoter mutation as an early event, whereas FGF3, FGF4, FGF19 or CCND1 amplification and TP53 and CDKN2A alterations appeared at more advanced stages in aggressive tumors. In 28% of the tumors, we identified genetic alterations potentially targetable by US Food and Drug Administration (FDA)-approved drugs. In conclusion, we identified risk factor-specific mutational signatures and defined the extensive landscape of altered genes and pathways in HCC, which will be useful to design clinical trials for targeted therapy.