Chemokine-driven lymphocyte infiltration: an early intratumoural event determining long-term survival in resectable hepatocellular carcinoma

Hepatic Natural Killer Cells: Organ-Specific Sentinels of Liver Immune Homeostasis and Physiopathology

The liver is considered a preferential tissue for NK cells residency. In humans, almost 50% of all intrahepatic lymphocytes are NK cells that are strongly imprinted in a liver-specific manner and show a broad spectrum of cellular heterogeneity. Hepatic NK (he-NK) cells play key roles in tuning liver immune response in both physiological and pathological conditions. Therefore, there is a pressing need to comprehensively characterize human he-NK cells to better understand the related mechanisms regulating their effector-functions within the dynamic balance between immune-tolerance and immune-surveillance. This is of particular relevance in the liver that is the only solid organ whose parenchyma is constantly challenged on daily basis by millions of foreign antigens drained from the gut. Therefore, the present review summarizes our current knowledge on he-NK cells in the light of the latest discoveries in the field of NK cell biology and clinical relevance.

Alcohol and hepatocellular carcinoma

BACKGROUND

Alcohol is classified as a Group 1 carcinogen by the International Agency for Research on Cancer because it induces hepatocellular carcinoma (among other cancers) in humans. An excessive alcohol intake may result in fatty liver, acute/chronic hepatitis, and cirrhosis and eventually lead to hepatocellular carcinoma. It has been reported that alcohol abuse increases the relative risk of hepatocellular carcinoma by 3- to 10-fold.

AIM AND METHODS

To clarify the known mechanisms of alcohol-related carcinogenesis, we searched Pubmed using the terms alcohol and immune mechanism, alcohol and cancer, and immune mechanism and cancer and summarized the articles as a qualitative review.

RESULTS

From a clinical perspective, it is well known that alcohol interacts with other factors, such as smoking, viral hepatitis, and diabetes, leading to an increased risk of hepatocellular carcinoma. There are several possible mechanisms through which alcohol may induce liver carcinogenicity, including the mutagenic effects of acetaldehyde and the production of ROS due to the excessive hepatic deposition of iron. Furthermore, it has been reported that alcohol accelerates hepatitis C virus-induced liver tumorigenesis through TLR4 signaling. Despite intense investigations to elucidate the mechanisms, they remain poorly understood.

CONCLUSION

This review summarizes the recent findings of clinical and pathological studies that have investigated the carcinogenic effects of alcohol in the liver.

TM6SF2 E167K Variant Overexpression Promotes Expression of Inflammatory Cytokines in the HCC Cell Line HEPA 1-6

Background and Aims: Accumulated evidence has shown that chronic liver inflammation is one of the main risks of hepatocellular carcinoma (HCC), and E167K variant of the transmembrane 6 superfamily member 2 (TM6SF2) plays an important role in the progression of chronic liver diseases and HCC. The aim of this study was to explore effects of the TM6SF2 E167K variant on expression of the inflammatory cytokines TNF-α, IL-2, IL-6 and IL-8 in the HCC cell line HEPA 1-6. Methods: HEPA 1-6 cells were infected with lentivirus containing either the TM6SF2 E167K variant or TM6SF2 wild-type, or control plasmids. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were conducted to analyze the expression of the inflammatory cytokines TNF-α, IL-2, IL-6 and IL-8. A t-test was used for statistical analysis. Results: Compared with the control group and TM6SF2 overexpression group, the relative expression of IL-2 and IL-6 mRNAs were significantly elevated in the TM6SF2 E167K overexpression group (p < 0.05). The relative mRNA expression of IL-8 in the TM6SF2 and TM6SF2 E167K overexpression groups were increased compared to the control group (p < 0.05). No obvious differences were observed for the expression of TNF-α in each group. The expression of TNF-α, IL-2, IL-6 and IL-8 that was tested by western blotting showed the same trends as the qRT-PCR results. Conclusions: In conclusion, the E167K variant of the TM6SF2 gene could promote the expression of inflammatory cytokines IL-2 and IL-6 in HEPA 1-6 cells, suggesting that the TM6SF2 E167K variant may accelerate the progression of HCC.

Systems Challenges of Hepatic Carcinomas: A Review

Hepatocellular Carcinoma (HCC) is ubiquitous in its prevalence in most of the developing countries. In the era of systems biology, multi-omics has evinced an extensive approach to define the underlying mechanism of disease progression. HCC is a multifactorial disease and the investigation of progression of liver cirrhosis becomes much extensive with cultivating omics approaches. We have performed a comprehensive review about such challenges in multi-omics approaches that are concerned to identify the immunological, genetics and epidemiological factors associated with HCC.

Immune activation underlies a sustained clinical response to Yttrium-90 radioembolisation in hepatocellular carcinoma

OBJECTIVES

Yttrium-90 (Y90)-radioembolisation (RE) significantly regresses locally advanced hepatocellular carcinoma and delays disease progression. The current study is designed to deeply interrogate the immunological impact of Y90-RE, which elicits a sustained therapeutic response.

DESIGN

Time-of-flight mass cytometry and next-generation sequencing (NGS) were used to analyse the immune landscapes of tumour-infiltrating leucocytes (TILs), tumour tissues and peripheral blood mononuclear cells (PBMCs) at different time points before and after Y90-RE.

RESULTS

TILs isolated after Y90-RE exhibited signs of local immune activation: higher expression of granzyme B (GB) and infiltration of CD8⁺ T cells, CD56⁺ NK cells and CD8⁺ CD56⁺ NKT cells. NGS confirmed the upregulation of genes involved in innate and adaptive immune activation in Y90-RE-treated tumours. Chemotactic pathways involving CCL5 and CXCL16 correlated with the recruitment of activated GB⁺CD8⁺ T cells to the Y90-RE-treated tumours. When comparing PBMCs before and after Y90-RE, we observed an increase in tumour necrosis factor-α on both the CD8⁺ and CD4⁺ T cells as well as an increase in percentage of antigen-presenting cells after Y90-RE, implying a systemic immune activation. Interestingly, a high percentage of PD-1⁺/Tim-3⁺CD8⁺ T cells coexpressing the homing receptors CCR5 and CXCR6 denoted Y90-RE responders. A prediction model was also built to identify sustained responders to Y90-RE based on the immune profiles from pretreatment PBMCs.

CONCLUSION

High-dimensional analysis of tumour and systemic immune landscapes identified local and systemic immune activation that corresponded to the sustained response to Y90-RE. Potential biomarkers associated with a positive clinical response were identified and a prediction model was built to identify sustained responders prior to treatment.

Clinicopathologic and prognostic significance of tumor-infiltrating CD8+ T cells in patients with hepatocellular carcinoma: A meta-analysis

BACKGROUND

In patients with hepatocellular carcinoma (HCC), the clinicopathologic and prognostic roles of tumor-infiltrating CD8+ T cells for survival are still controversial. A meta-analysis was performed to resolve this issue.

METHODS

We identified studies from PubMed, Embase, and the Cochrane Library to evaluate the clinicopathologic and prognostic value of tumor-infiltrating CD8+ T cells in patients with HCC. A meta-analysis was conducted to estimate clinicopathologic characteristics, overall survival (OS), and disease-free survival. The hazard ratio (HR) and 95% confidence interval (CI) were calculated employing fixed-effect or random-effect models depending on the heterogeneity of the included trials.

RESULTS

A total of 3509 patients from 21 observational studies were enrolled. The meta-analysis revealed that high levels of intratumoral CD8+ tumor-infiltrating lymphocytes (TILs) were associated with better OS (OS; HR = 0.676, P = .001) and disease-free survival (disease-free survival [DFS]; HR = 0.712, P = .002). The pooled analysis also demonstrated high density of infiltration of CD8+ TILs in margin of tumor (MT) was statistically significant associated with better OS (HR = 0.577; P <.001). Moreover, the patients with low CD8+ TILs infiltration had negative HBSAg (OR = 1.67, P = .02), large tumor size (OR = 1.74, P <.01), and later TNM stage (OR = 1.70, P <.01).

CONCLUSIONS

Our findings suggested that low levels of CD8+ TILs predict large tumor size, later TNM stage and might be a promising prognostic factor of HCC especially for Asian patients. High-quality randomized controlled trials are needed to determine if CD8+ TILs could serve as targets for immunotherapy in hepatocellular carcinoma.

Prognostic value of tumor-infiltrating lymphocytes in hepatocellular carcinoma: A meta-analysis

BACKGROUND

In patients with hepatocellular carcinoma (HCC), the prognostic role of tumor-infiltrating lymphocytes (TILs) for survival is still controversial. A meta-analysis was performed to investigate the prognostic effect of TILs in HCC.

METHODS

We identify studies from PubMed, Embase, and the Cochrane Library to evaluate the prognostic value of TILs in patients with HCC. A meta-analysis was conducted to estimate overall survival and disease-free survival. The hazard ratio (HR) and 95% confidence interval (CI) were calculated employing fixed-effect or random-effect models depending on the heterogeneity of the included trials.

RESULTS

A total of 7905 patients from 46 observational studies were enrolled. For TILs subsets, the density of CD8+, FOXP3+, CD3+, and Granzyme B+ lymphocytes was significantly associated with improved survival (P < .05). The density of FOXP3+ TILs in intratumor (IT) was the most significant prognostic marker (pooled HR = 1.894; 95% CI = 1.659-2.164; P < .001). Patients with high infiltration of CD8+ TILs in IT (pooled HR = 0.676; 95% CI = 0.540-0.845; P = .001) or in margin of tumor (MT) (pooled HR = 0.577; 95% CI = 0.437-0.760; P < .001) had better OS. The pooled analysis revealed that high density of Granzyme B+ T-lymphocytes in IT was statistically significant associated with better OS (pooled HR = 0.621; 95% CI = 0.516-0.748; P < .001) and DFS (pooled HR = 0.678; 95% CI = 0.563-0.815; P < .001). It was interesting that high density of CD3+ in IT foreboded worse OS (pooled HR = 1.008; 95% CI = 1.000-1.015; P = .037), but better DFS (pooled HR = 0.596; 95% CI = 0.374-0.948; P = .029).

CONCLUSION

Our findings suggested that some TIL subsets could serve as prognostic biomarkers in HCC. High-quality randomized controlled trials are needed to determine if these TILs could serve as targets for immunotherapy in HCC.

Natural Killer Cell Dysfunction in Hepatocellular Carcinoma: Pathogenesis and Clinical Implications

Hepatocellular carcinoma (HCC) is currently the third leading cause of malignancy-related mortalities worldwide. Natural killer (NK) cells are involved in the critical role of first line immunological defense against cancer development. Defects in NK cell functions are recognized as important mechanisms for immune evasion of tumor cells. NK cell function appears to be attenuated in HCC, and many previous reports suggested that NK cells play a critical role in controlling HCC, suggesting that boosting the activity of dysfunctional NK cells can enhance tumor cell killing. However, the detailed mechanisms of NK cell dysfunction in tumor microenvironment of HCC remain largely unknown. A better understanding of the mechanisms of NK cell dysfunction in HCC will help in the NK cell-mediated eradication of cancer cells and prolong patient survival. In this review, we describe the various mechanisms underlying human NK cell dysfunction in HCC. Further, we summarize current advances in the approaches to enhance endogenous NK cell function and in adoptive NK cell therapies, to cure this difficult-to-treat cancer.

Non-hematopoietic Control of Peripheral Tissue T Cell Responses: Implications for Solid Tumors

In response to pathological challenge, the host generates rapid, protective adaptive immune responses while simultaneously maintaining tolerance to self and limiting immune pathology. Peripheral tissues (e.g., skin, gut, lung) are simultaneously the first site of pathogen-encounter and also the location of effector function, and mounting evidence indicates that tissues act as scaffolds to facilitate initiation, maintenance, and resolution of local responses. Just as both effector and memory T cells must adapt to their new interstitial environment upon infiltration, tissues are also remodeled in the context of acute inflammation and disease. In this review, we present the biochemical and biophysical mechanisms by which non-hematopoietic stromal cells and extracellular matrix molecules collaborate to regulate T cell behavior in peripheral tissue. Finally, we discuss how tissue remodeling in the context of tumor microenvironments impairs T cell accumulation and function contributing to immune escape and tumor progression.

Treatment of advanced hepatocellular carcinoma: immunotherapy from checkpoint blockade to potential of cellular treatment

The absence of potent therapeutic option accounts for the dismal prognosis of advanced hepatocellular carcinoma (HCC) with high mortality and recurrence rate. For a decade, sorafenib is the only approved systemic drug in the first-line setting and warrants as the standard-of-care for HCC in the advanced stage. Given the common failures of chemotherapies and targeted therapies in the field of HCC treatment, promising breakthroughs were eagerly needed and until recently, immunotherapies have opened a new era of anticancer treatment. The liver organ is perceived as "immunotolerant" owing to its functional role, and the hepatic immune balance is found to be deregulated during chronic liver inflammation and HCC tumorigenesis. Restoring a competent immunity by mitigation of immunosuppression signals is a contemporary approach. In this regard, novel immune checkpoint inhibitors have revolutionized cancer pharmacological treatment options with remarkable clinical outcomes in hematologic malignancy and multiple solid tumors including advanced HCC. Nivolumab, an immunotherapeutic agent to block programmed cell death protein 1 (PD-1), showed high efficacy potential for patients progressed with sorafenib and granted accelerated approval by the US Food and Drug Administration (FDA) recently. The development of this class of immunotherapeutic drug is currently based on myriad studies established on the role of T-cell mediated immunosuppression through immune checkpoints. Heterogeneous results have led to further explorations to the profile of oncogenic processes and signaling pathways associated with PD1/PD-L1 axis. Emerging evidence from preclinical studies implicate natural killer (NK) cells as a mediator to the PD-1 checkpoint signaling immunoevasion. The strategy of adopting immunomodulating ability of NK cells by immune checkpoints inhibitors is potential to additive effects in stimulating anticancer immunity. This idea is not entirely newfound but has recently gained prominence because of advances in defining phenotypic heterogeneity of NK cell populations. The physiological significance and synergistic value of NK cells await further investigation in clinical trials. In this review, an overview of the treatment paradigm shift of HCC management is presented. Current knowledge concerning immunological mechanisms of immune checkpoints attributed to T cell is further discussed and relevant ongoing clinical trials are summarized. We proposed that NK cells should be viewed as part of the network of checkpoint immunoevasion and delineate current evidence of translational clinical research in this area. It is conceivable that immune checkpoint inhibitors in combination with NK cell-based therapeutic strategies will be great promise for treatment of advanced HCC.

Tumor-immune profiling of murine syngeneic tumor models as a framework to guide mechanistic studies and predict therapy response in distinct tumor microenvironments

Mouse syngeneic tumor models are widely used tools to demonstrate activity of novel anti-cancer immunotherapies. Despite their widespread use, a comprehensive view of their tumor-immune compositions and their relevance to human tumors has only begun to emerge. We propose each model possesses a unique tumor-immune infiltrate profile that can be probed with immunotherapies to inform on anti-tumor mechanisms and treatment strategies in human tumors with similar profiles. In support of this endeavor, we characterized the tumor microenvironment of four commonly used models and demonstrate they encompass a range of immunogenicities, from highly immune infiltrated RENCA tumors to poorly infiltrated B16F10 tumors. Tumor cell lines for each model exhibit different intrinsic factors in vitro that likely influence immune infiltration upon subcutaneous implantation. Similarly, solid tumors in vivo for each model are unique, each enriched in distinct features ranging from pathogen response elements to antigen presentation machinery. As RENCA tumors progress in size, all major T cell populations diminish while myeloid-derived suppressor cells become more enriched, possibly driving immune suppression and tumor progression. In CT26 tumors, CD8 T cells paradoxically increase in density yet are restrained as tumor volume increases. Finally, immunotherapy treatment across these different tumor-immune landscapes segregate into responders and non-responders based on features partially dependent on pre-existing immune infiltrates. Overall, these studies provide an important resource to enhance our translation of syngeneic models to human tumors. Future mechanistic studies paired with this resource will help identify responsive patient populations and improve strategies where immunotherapies are predicted to be ineffective.

Perivascular Tumor-Infiltrating Leukocyte Scoring for Prognosis of Resected Hepatocellular Carcinoma Patients

Liver resection is a curative treatment for hepatocellular carcinoma (HCC). Tumor-infiltrating leukocytes (TILs) are important players in predicting HCC recurrence. However, the invasive margin could not be confirmed as relevant for HCC. The migration of immune cells into HCC may originate from intratumoral vessels. No previous study has examined perivascular (PV) infiltration. Tumors from 60 patients were examined. Immunohistochemistry was performed against CD3, CD8, CD20, and CD66b. TILs were counted in the PV regions using an algorithm for quantification of the tumor immune stroma (QTiS). The results were correlated with overall (OS) and disease-free survival (DFS), clinical parameters, and laboratory values. PV infiltration of TILs was predominant in resected HCC. Higher PV infiltration of CD3⁺ (p = 0.016) and CD8⁺ (p = 0.028) independently predicted better OS and DFS, respectively. CD20⁺ showed a trend towards better DFS (p = 0.076). Scoring of CD3⁺, CD8⁺, and CD20⁺ independently predicted OS and DFS (p < 0.01). The amount of perivascular-infiltrating CD3⁺ cells is an independent predictor of better OS, and CD8⁺ cells independently predict prolonged DFS. Our novel perivascular infiltration scoring (PVIS) can independently predict both DFS and OS in resected HCC patients.

Reduced CD160 Expression Contributes to Impaired NK-cell Function and Poor Clinical Outcomes in Patients with HCC

: We previously reported that deficiencies in natural killer (NK)-cell number and function play an important role in the progression of hepatocellular carcinoma (HCC). However, the mechanisms underlying this phenomenon remain obscure. In this study, we analyzed the expression of CD160 on intrahepatic NK cells by evaluating peritumoral and intratumoral tissues of 279 patients with HCC and 20 healthy livers. We observed reduced expression of CD160 on intratumoral NK cells, and patients with lower CD160 cell densities within tumors exhibited worse disease and a higher recurrence rate. High-resolution microarray and gene set enrichment analysis of flow cytometry-sorted primary intrahepatic CD160⁺ and CD160^- NK cells of healthy livers indicated that human CD160⁺ NK cells exhibited functional activation, high IFNγ production, and NK-mediated immunity. In addition, global transcriptomic analysis of sorted peritumoral and intratumoral CD160⁺ NK cells revealed that intratumoral CD160⁺ NK cells are more exhausted than peritumoral CD160⁺ NK cells and produce less IFNγ. High levels of TGFβ1 interfered with production of IFNγ by CD160⁺ NK cells, blocking of which specifically restored IFNγ production in CD160⁺ NK cells to normal levels. These findings indicate that reduced numbers of CD160⁺ NK cells, together with the functional impairment of CD160⁺ NK cells by TGFβ1, contribute to tumor immune escape. In addition, restoring the expression of CD160 and blocking TGFβ1 appear a promising therapeutic strategy against liver cancer. SIGNIFICANCE: These findings show that reduced number and function of CD160⁺ NK cells in the tumor microenvironment contributes to immune escape of HCC; blocking TGFβ1 restores IFNγ production of CD160⁺ NK cells.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/23/6581/F1.large.jpg.

Natural Killer Cells in Liver Disease and Hepatocellular Carcinoma and the NK Cell-Based Immunotherapy

Nature killer (NK) cells play a critical role in host innate and adaptive immune defense against viral infections and tumors. NK cells are enriched in liver hematopoietic cells with unique NK repertories and functions to safeguard liver cells against hepatitis virus infection or malignancy transformation. However, accumulating evidences were found that the NK cells were modulated by liver diseases and liver cancers including hepatocellular carcinoma (HCC) and showed impaired functions failing to activate the elimination of the viral-infected cells or tumor cells and were further involved in the pathogenesis of liver injury and inflammation. The full characterization of circulation and intrahepatic NK cell phenotype and function in liver disease and liver cancer has not only provided new insight into the disease pathogenesis but has also discovered new targets for developing new NK cell-based therapeutic strategies. This review will discuss and summarize the NK cell phenotypic and functional changes in liver disease and HCC, and the NK cell-based immunotherapy approaches and progresses for cancers including HCC will also be reviewed.

Landscape of immune microenvironment in hepatocellular carcinoma and its additional impact on histological and molecular classification

Immune cells constitute an important element of tumor tissue. Accumulating evidence indicates their clinicopathological significance in predicting prognosis and therapeutic efficacy. Nonetheless, the combinations of immune cells forming the immune microenvironment and their association with histological findings remain largely unknown. Moreover, it is unclear which immune cells or immune microenvironments are the most prognostically significant. Here, we comprehensively analyzed the immune microenvironment and its intratumor heterogeneity in 919 regions of 158 hepatocellular carcinomas (HCCs), and the results were compared with the corresponding histological and prognostic data. Consequently, we classified the immune microenvironment of HCC into three distinct immunosubtypes: Immune-high, Immune-mid, and Immune-low. The Immune-high subtype was characterized by increased B-/plasma-cell and T cell infiltration, and the Immune-high subtype and B-cell infiltration were identified as independent positive prognostic factors. Varying degrees of intratumor heterogeneity of the immune microenvironment were observed, some of which reflected the multistep nature of HCC carcinogenesis. However, the predominant pattern of immunosubtype and immune cell infiltration of each tumor was prognostically important. Of note, the Immune-high subtype was associated with poorly differentiated HCC, cytokeratin 19 (CK19)⁺ , and/or Sal-like protein 4 (SALL4)⁺ high-grade HCC, and Hoshida's S1/Boyault's G2 subclasses. Furthermore, patients with high-grade HCC of the predominant Immune-high subtype had significantly better prognosis. These results provide a rationale for evaluating the immune microenvironment in addition to the usual histological/molecular classification of HCC.

CONCLUSION

The immune microenvironment of HCC can be classified into three immunosubtypes (Immune-high, Immune-mid, and Immune-low) with additional prognostic impact on histological and molecular classification of HCC. (Hepatology 2018).

Immune Gene Expression Profile in Hepatocellular Carcinoma and Surrounding Tissue Predicts Time to Tumor Recurrence

BACKGROUND

The antitumor immune response may play a major role in the clinical outcome of hepatocellular carcinoma (HCC). We characterized the liver immune microenvironment by direct hybridization of RNA extracted from HCC and nontumorous tissues.

METHODS

RNA was extracted from frozen liver tissue samples of HCC (T; n = 30) and nontumorous tissues (NT; n = 33) obtained from 38 patients. Matched samples were available for 25 patients. The immune gene expression profile was analyzed with the nCounter GX Human Immunology v2 system (NanoString Technologies), which detects the expression levels of 579 immune response-related genes simultaneously.

RESULTS

Since the immune gene expression profile of T and NT tissues was significantly different, the prognostic relevance of the liver immune microenvironment was evaluated in the T and NT samples separately. Unsupervised clustering detected two main clusters of immune gene expression both in T and in NT liver samples. In both cases, the expression clusters identified groups of patients with a significantly different median time to HCC recurrence (TTR) but similar overall survival. Based on T tissue, two groups with median TTR of 19 and 127 months, respectively, were detected (p < 0.005). Expression of genes related to T-cell activation was associated with longer TTR. The analysis of NT tissue discriminated subsets of patients with median TTR of 22 and 68 months (p < 0.05). In contrast to T tissue, a predominant inflammatory immune environment was associated with shorter TTR.

CONCLUSIONS

Immune gene expression profiles predictive of TTR could be identified both in HCC and in adjacent cirrhotic tissues. Longer TTR was associated with overexpression in T tissue and downregulation in NT tissue of the immune response and of inflammation-related genes.

Immunogenomic Analyses of Advanced Serous Ovarian Cancer Reveal Immune Score is a Strong Prognostic Factor and an Indicator of Chemosensitivity

Purpose: Ovarian cancer is one of the first human cancers for which in situ immune response was reported to be important for the clinical outcome. To elucidate the mechanistic relationship between immune repertoire and cancer genotype in ovarian cancer, the development of a well-defined immune score for ovarian cancer is required.Experimental Design: From a collection of 2,203 patient samples of advanced ovarian cancer from public available resources, we evaluated the prognostic values for a compendium of immune marker genes and proposed an immune score. The relationships between immune score, tumor-infiltrating immune cells, cancer genotypes, and their impact on patient outcome were characterized.Results: Loss of chemokine and IFNγ pathway genes is frequent in ovarian cancer and is significantly associated with low immune score and poor outcome. Chemotherapy can increase the immune score of tumors by inducing the expression of IFNγ inducible chemokines. High immune score is significantly associated with BRCA1/2 mutation status and the response to chemotherapy. Multivariate analysis revealed that immune score is a strong predictor of patient survival and the response to immunotherapy.Conclusions: Our results reveal the drivers of the immune repertoire of advanced ovarian cancer and demonstrate the importance of immune score as an independent prognostic signature and a potent indicator of intratumoral immune status. Clin Cancer Res; 24(15); 3560-71. ©2018 AACR.

Oncolytic viruses as engineering platforms for combination immunotherapy

To effectively build on the recent successes of immune checkpoint blockade, adoptive T cell therapy and cancer vaccines, it is critical to rationally design combination strategies that will increase and extend efficacy to a larger proportion of patients. For example, the combination of anti-cytotoxic T lymphocyte-associated antigen 4 (CTLA4) and anti-programmed cell death protein 1 (PD1) immune checkpoint inhibitors essentially doubles the response rate in certain patients with metastatic melanoma. However, given the heterogeneity of cancer, it seems likely that even more complex combinations of immunomodulatory agents may be required to obtain consistent, durable therapeutic responses against a broad spectrum of cancers. This carries serious implications in terms of toxicities for patients, feasibility for care providers and costs for health-care systems. A compelling solution is offered by oncolytic viruses (OVs), which can be engineered to selectively replicate within and destroy tumour tissue while simultaneously augmenting antitumour immunity. In this Opinion article, we argue that the future of immunotherapy will include OVs that function as multiplexed immune-modulating platforms expressing factors such as immune checkpoint inhibitors, tumour antigens, cytokines and T cell engagers. We illustrate this concept by following the trials and tribulations of tumour-reactive T cells from their initial priming through to the execution of cytotoxic effector function in the tumour bed. We highlight the myriad opportunities for OVs to help overcome critical barriers in the T cell journey, leading to new synergistic mechanisms in the battle against cancer.

Ambiguous roles of innate lymphoid cells in chronic development of liver diseases

Innate lymphoid cells (ILCs) are defined as a distinct arm of innate immunity. According to their profile of secreted cytokines and lineage-specific transcriptional factors, ILCs can be categorized into the following three groups: group 1 ILCs (including natural killer (NK) cells and ILC1s) are dependent on T-bet and can produce interferon-γ; group 2 ILCs (ILC2s) are dependent on GATA3 and can produce type 2 cytokines, including interleukin (IL)-5 and IL-13; and, group 3 ILCs (including lymphoid tissue-like cells and ILC3s) are dependent on RORγt and can produce IL-22 and IL-17. Collaborative with adaptive immunity, ILCs are highly reactive innate effectors that promptly orchestrate immunity, inflammation and tissue repair. Dysregulation of ILCs might result in inflammatory disorders. Evidence regarding the function of intrahepatic ILCs is emerging from longitudinal studies of inflammatory liver diseases wherein they exert both physiological and pathological functions, including immune homeostasis, defenses and surveillance. Their overall effect on the liver depends on the balance of their proinflammatory and antiinflammatory populations, specific microenvironment and stages of immune responses. Here, we review the current data about ILCs in chronic liver disease progression, to reveal their roles in different stages as well as to discuss their therapeutic potency as intervention targets.

The immune contexture of hepatocellular carcinoma predicts clinical outcome

The general relevance of the immune system for cancer development and therapy is increasingly recognized. However and although the immune contexture of most human cancer types has been determined, a global characterisation of the immune tumour microenvironment in hepatocellular carcinoma (HCC) is lacking. Equally, differences in the immune contexture of HCC between different patient subgroups and its effect on survival remain to be established. Here we report an in silico analysis of the immune contexture of human HCC. Using large deep sequencing HCC tumour, adjacent non-tumour and healthy liver high-dimensional data sets, we were able to reveal previously unrecognized differences in the immune contexture of HCC. Strikingly, we found that different etiologies and HCC stages were not associated with major changes in the immune contexture. In contrast, the presence of T cells and cytotoxic cells as well as the absence of macrophages and Th2 cells positively correlated with patient survival. Based on these novel findings, we developed a prognostic score that accurately distinguishes between patients with good and poor survival. Our study provides the first global characterisation of the immune contexture of HCC and will have direct implications for future HCC therapies.

Effect of CCL5 expression in the recruitment of immune cells in triple negative breast cancer

Triple negative breast cancer (TNBC) is the most aggressive form of breast cancer with limited options of targeted therapy. Recent findings suggest that the clinical course of TNBC may be modified by the presence of tumor-infiltrating lymphocytes (TILs) and chemokine's expression, such as CCL5. Diverse studies have shown that CCL5 suppresses anti-tumor immunity and it has been related to poor outcome in different types of cancer while in other studies, this gene has been related with a better outcome. We sought to determine the association of CCL5 with the recruitment of TILs and other immune cells. With this aim we evaluated a retrospective cohort of 72 TNBC patients as well as publicly available datasets. TILs were correlated with residual tumor size after neoadjuvant chemotherapy (NAC) and CCL5 expression. In univariate analysis, TILs and CCL5 were both associated to the distant recurrence free survival; however, in a multivariate analysis, TILs was the only significant marker (HR = 0.336; 95%IC: 0.150-0.753; P = 0.008). CIBERSORT analysis suggested that a high CCL5 expression was associated with recruitment of CD8 T cells, CD4 activated T cells, NK activated cells and macrophages M1. The CD8A gene (encoding for CD8) was associated with an improved outcome in several public breast cancer datasets.

Pretreatment prognostic factors of survival and late toxicities for patients with nasopharyngeal carcinoma treated by simultaneous integrated boost intensity-modulated radiotherapy

Background

To scrutinize the pretreatment prognosticators on survival and late toxicities in a homogenous cohort of nasopharyngeal carcinoma (NPC) patients treated by simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT).

Methods

A total of 219 non-distant metastatic NPC patients consecutively treated by SIB-IMRT at a single institute were collected. The pretreatment factors including the socio-demographic variables, TNM stages, gross tumor volume (GTV), Epstein-Barr virus (EBV)-DNA, and hematologic inflammatory markers were analyzed. Cox model was used to screen the prognostic factors of late toxicities and four survival outcomes including locoregional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS), failure-free survival (FFS), and overall survival (OS).

Results

Statistically significant inter-correlations were observed between the values of EBV-DNA, some hematologic inflammatory markers, GTV, and N classification. The 5-year LRRFS, DMFS, FFS, and OS rates were 87.9%, 89.4%, 79.4%, and 81.3%, respectively. Multivariate analysis revealed that advanced N classification (N2–3 vs. N0–1) remained the only significant negative prognosticator for all the four survival outcomes. An increased monocyte percentage and a decreased lymphocyte-to-monocyte ratio were significantly associated with poorer FFS and OS, respectively. Larger GTV was observed to be predictive of poorer LRRFS. Patients with T3–4 (HR: 3.5, 95% CI: 1.0–12.1, p = 0.048) or higher GTV (HR: 1.006, 95% CI: 1.001–1.011, p = 0.027) were associated with higher incidence of radiation neuropathy.

Conclusion

N classification remains the most significant survival predictor for NPC patients treated by SIB-IMRT after adjusting these biomarkers. GTV impacts not only on locoregional control but also radiation neuropathy.

C-C chemokine receptor type 1 mediates osteopontin-promoted metastasis in hepatocellular carcinoma

In the hepatocellular carcinoma (HCC) microenvironment, chemokine receptors play a critical role in tumorigenesis and metastasis. Our previous studies have found that osteopontin (OPN) is a promoter for HCC metastasis. However, the role of chemokine receptors in OPN-induced HCC metastasis remains unclear. In this study, we demonstrate that OPN is dramatically elevated in HCC tissues with metastasis and that high expression of OPN correlates with poorer overall survival and higher recurrence rate. OPN upregulates chemokine receptor expression, migration, invasion and pulmonary metastasis in HCC. We find that C-C chemokine receptor type 1 (CCR1) and C-X-C chemokine receptor type 6 (CXCR6) are the most upregulated chemokine receptors induced by OPN. CCR1 knockdown results in reduction of migration, invasion and pulmonary metastasis induced by OPN in vitro and in vivo, whereas CXCR6 knockdown does not reverse OPN-promoted migration and invasion. Moreover, OPN upregulates the expression of CCR1 through activating phosphoinositide 3-kinase (PI3K)/AKT and hypoxia-inducible factor 1α (HIF-1α) in HCC cells. Furthermore, blockade of OPN-CCR1 axis with CCR1 antagonist significantly restrains the promoting effects of OPN on HCC progression and metastasis. In human HCC tissues, OPN expression shows significantly positive correlation with CCR1 expression, and the patients with high levels of both OPN and CCR1 have the most dismal prognosis. Collectively, our results indicate that the OPN-CCR1 axis in HCC is important for accelerating tumor metastasis and that CCR1 is a potential therapeutic target for controlling metastasis in HCC patients with high OPN.

Distinct role of interleukin-6 and tumor necrosis factor receptor-1 in oval cell- mediated liver regeneration and inflammation-associated hepatocarcinogenesis

Interleukin 6 (IL6), tumor necrosis factor α (TNFα) and TNF receptor-1(TNFR1) have been shown to involve in oval cell proliferation and hepatocellular carcinoma (HCC) development. However, their role in these processes is still unclear. In the present study, by using hepatocytes-specific DDB1 deletion mouse models, we explored the role and mechanism of IL6, TNFα and TNFR1 in oval cell proliferation and HCC development in the context of inflammation, which is the common features of HCC pathogenesis in humans. Our results showed that IL6 promotes oval cell proliferation and liver regeneration, while TNFα/TNFR1 does not affect this process. Deletion of IL6 accelerates HCC development and increases tumor burden. The number of natural killer(NK) cells is significantly decreased in tumors without IL6, implying that IL6 suppresses HCC by NK cells. In contrast to IL6, TNFR1-mediated signaling pathway promotes HCC development, and deletion of TNFR1 reduced tumor incidence. Increased apoptosis, compensatory proliferation and activation of MAPK/MEK/ERK cascade contribute to the oncogenic function of TNFR1-mediated signaling pathway. Intriguingly, deletion of TNFα accelerates tumor development, which shows divergent roles of TNFα and TNFR1 in hepatocarcinogenesis.

Targeting gut microbiota in hepatocellular carcinoma: probiotics as a novel therapy

Hepatocellular carcinoma (HCC), the most common primary liver cancer, is one of the dreaded complications of chronic liver disease. Recent experimental and clinical studies have revealed that the alteration of gut-liver axis plays a pivotal role in the onset of chronic liver diseases, including HCC. Altered gut microbiota and endotoxemia are increasingly recognized as critical components in promoting the progression of chronic liver diseases to HCC. Probiotics have been suggested as a novel, safe and cost-effective approach to prevent or treat HCC. Mechanisms by which probiotics exerts their anti-cancer effects include their ability to bind carcinogens, modulation of gut microbiota, improvement of intestinal barrier function, and immunomodulation. This review summarizes the literature findings of the changes in gut microbiota linked to HCC, and discusses the possible therapeutic implications of probiotics for HCC.

MiRSEA: Discovering the pathways regulated by dysfunctional MicroRNAs

Recent studies have shown that dysfunctional microRNAs (miRNAs) are involved in the progression of various cancers. Dysfunctional miRNAs may jointly regulate their target genes and further alter the activities of canonical biological pathways. Identification of the pathways regulated by a group of dysfunctional miRNAs could help uncover the pathogenic mechanisms of cancer and facilitate development of new drug targets. Current miRNA-pathway analyses mainly use differentially-expressed miRNAs to predict the shared pathways on which they act. However, these methods fail to consider the level of differential expression level, which could improve our understanding of miRNA function. We propose a novel computational method, MicroRNA Set Enrichment Analysis (MiRSEA), to identify the pathways regulated by dysfunctional miRNAs. MiRSEA integrates the differential expression levels of miRNAs with the strength of miRNA pathway associations to perform direct enrichment analysis using miRNA expression data. We describe the MiRSEA methodology and illustrate its effectiveness through analysis of data from hepatocellular cancer, gastric cancer and lung cancer. With these analyses, we show that MiRSEA can successfully detect latent biological pathways regulated by dysfunctional miRNAs. We have implemented MiRSEA as a freely available R-based package on CRAN (https://cran.r-project.org/web/packages/MiRSEA/).

Role of Chemokines in Thyroid Cancer Microenvironment: Is CXCL8 the Main Player?

Tumor-related inflammation does influence the biological behavior of neoplastic cells and ultimately the patient's outcome. With specific regard to thyroid cancer, the issue of tumor-associated inflammation has been extensively studied and recently reviewed. However, the role of chemokines, which play a crucial role in determining the immuno-phenotype of tumor-related inflammation, was not addressed in previous reviews on the topic. Experimental evidence shows that thyroid cancer cells actively secrete a wide spectrum of chemokines and, at least for some of them, solid scientific data support a role for these immune-active molecules in the aggressive behavior of the tumor. Our proposal for a review article on chemokines and thyroid cancer stems from the notion that chemokines, besides having the ability to attract and maintain immune cells at the tumor site, also produce several pro-tumorigenic actions, which include proangiogenetic, cytoproliferative, and pro-metastatic effects. Studies taking into account the role of CCL15, C-X-C motif ligand 12, CXCL16, CXCL1, CCL20, and CCL2 in the context of thyroid cancer will be reviewed with particular emphasis on CXCL8. The reason for focusing on CXCL8 is that this chemokine is the most studied one in human malignancies, displaying multifaceted pro-tumorigenic effects. These include enhancement of tumor cells growth, metastatization, and angiogenesis overall contributing to the progression of several cancers including thyroid cancer. We aim at reviewing current knowledge on the (i) ability of both normal and tumor thyroid cells to secrete CXCL8; (ii) direct/indirect pro-tumorigenic effects of CXCL8 demonstrated by in vitro and in vivo studies specifically performed on thyroid cancer cells; and (iii) pharmacologic strategies proven to be effective for lowering CXCL8 secretion and/or its effects on thyroid cancer cells.

Boosting Natural Killer Cell-Based Immunotherapy with Anticancer Drugs: a Perspective

Natural killer (NK) cells efficiently recognize and kill tumor cells through several mechanisms including the expression of ligands for NK cell-activating receptors on target cells. Different clinical trials indicate that NK cell-based immunotherapy represents a promising antitumor treatment. However, tumors develop immune-evasion strategies, including downregulation of ligands for NK cell-activating receptors, that can negatively affect antitumor activity of NK cells, which either reside endogenously, or are adoptively transferred. Thus, restoration of the expression of NK cell-activating ligands on tumor cells represents a strategic therapeutic goal. As discussed here, various anticancer drugs can fulfill this task via different mechanisms. We envision that the combination of selected chemotherapeutic agents with NK cell adoptive transfer may represent a novel strategy for cancer immunotherapy.

Preoperative prediction of hepatocellular carcinoma with portal vein tumor thrombus based on conventional data

Hepatocellular carcinoma (HCC) has a high predilection with portal vein tumor thrombosis (PVTT). However, part of the PVTT type can be found only under the microscopy, which was namely as type I₀. The objective of this study was to establish a simple and inexpensive non-invasive model to predict the presentation of PVTT at HCC patients. A total of 815 HCC patients were retrospectively evaluated and randomly assigned into 2 groups: the training group (n = 408) and validation group (n = 407). A new index model, namely WγAL, was built to predict the presence of PVTT in the training subjects and was further validated in the validation subjects. At the optimal cutoff of 8.90, WγAL identified patients with a hazard ratio (HR) of 7.139 for the presence of PVTT. The area under receiver operating characteristic (AUROC) of WγAL was 0.795 (sensitivity: 71.9%; specificity: 78.6%) for differentiation between PVTT and non-PVTT patients in the training group. The AUROC of WγAL in differentiating patients with PVTT type I₀ from non-PVTT patients was 0.748 (sensitivity: 72.1%; specificity: 68.4%) with an HR of 5.355. In addition, WγAL > 8.90 was significantly associated with large tumors, multiple tumor numbers, TNM stage III-IV, metastasis, and overall survival in HCC patients. The novel predictive model represents a simple and inexpensive model that can identify the presence of PVTT in HCC patients with a high degree of accuracy, with important clinical significance in the future therapeutic management of HCC patients.

DAMP-TLR-cytokine axis dictates the fate of tumor

Random mutations leading to loss of cell cycle control is not a rare occurrence in an organism but the mutated cells are recognized and eliminated preventing the development of a tumor. These potentially tumorigenic cells release damage-associated molecular patterns (DAMPs), which are recognized by toll-like receptors (TLRs) on macrophages and dendritic cells. The initial TLR-DAMP interactions lead to different responses such as altered antigen presentation and cytokine release that directly affect T cell activation and removal of the tumorigenic cells. The indirect effects of TLR-DAMP interaction include chemokine-directed altered T cell trafficking, angiogenesis for both T cell infiltration and tumor cell metastasis, and alteration of intra-tumoral milieu contributing to the development of tumor cells heterogeneity. Thus, the initial TLR-DAMP interaction has a set of local effects that modulate tumor cell growth and heterogeneity and a disseminating set of central effects that dynamically affect T cell trafficking and functions. Herein, we argue that the DAMP-TLR-cytokine axis in the tumor microenvironment serves as the mainstay that orchestrates and regulates the pro- and anti-tumor elements which dynamically interact between themselves eventuating in tumor regression or growth. The knowledge of this TLR-based immuno-surveillance framework is a key to developing a novel immunotherapy against cancer.

Natural killer cells and tumor metastasis

Natural killer (NK) cells are cytotoxic lymphocytes that recognize tumor cells or stressed cells through 'missing-self' signals, such as altered or absent expression of MHC class I molecules. The function of NK cells is regulated by the activation or inhibition of receptors present on their surface. The activation of NK cells results in cytotoxic activity on target cells through release of toxic granules and inflammatory cytokines. However, NK cells infiltrating tumors have been frequently shown to exhibit a skewed phenotype that includes decreased antitumor activity and enhanced protumor activities, such as angiogenesis and metastasis. In fact, many studies have reported that tumor microenvironments induce a protumor phenotype in NK cells. Here, we review the biological properties of NK cells in the context of tumorigenesis and tumor progression, with a specific focus on the interactions between NK cells and critical tumor microenvironments, such as epithelial-to-mesenchymal transition, matrix metalloproteinases, and tumor-associated chronic inflammation in tumor metastasis.

Delineation of an immunosuppressive gradient in hepatocellular carcinoma using high-dimensional proteomic and transcriptomic analyses

The recent development of immunotherapy as a cancer treatment has proved effective over recent years, but the precise dynamics between the tumor microenvironment (TME), nontumor microenvironment (NTME), and the systemic immune system remain elusive. Here, we interrogated these compartments in hepatocellular carcinoma (HCC) using high-dimensional proteomic and transcriptomic analyses. By time-of-flight mass cytometry, we found that the TME was enriched in regulatory T cells (Tregs), tissue resident memory CD8⁺ T cells (T_RMs), resident natural killer cells (NK_Rs), and tumor-associated macrophages (TAMs). This finding was also validated with immunofluorescence staining on Foxp3⁺CD4⁺ and PD-1⁺CD8⁺ T cells. Interestingly, Tregs and T_RMs isolated from the TME expressed multiple markers for T-cell exhaustion, including PD-1, Lag-3, and Tim-3 compared with Tregs and T_RMs isolated from the NTME. We found PD-1⁺ T_RMs were the predominant T-cell subset responsive to anti-PD-1 treatment and significantly reduced in number with increasing HCC tumor progression. Furthermore, T-bet was identified as a key transcription factor, negatively correlated with PD-1 expression on memory CD8⁺ T cells, and the PD-1:T-bet ratio increased upon exposure to tumor antigens. Finally, transcriptomic analysis of tumor and adjacent nontumor tissues identified a chemotactic gradient for recruitment of TAMs and NK_Rs via CXCR3/CXCL10 and CCR6/CCL20 pathways, respectively. Taken together, these data confirm the existence of an immunosuppressive gradient across the TME, NTME, and peripheral blood in primary HCC that manipulates the activation status of tumor-infiltrating leukocytes and renders them immunocompromised against tumor cells. By understanding the immunologic composition of this gradient, more effective immunotherapeutics for HCC may be designed.

Identifying baseline immune-related biomarkers to predict clinical outcome of immunotherapy

As cancer strikes, individuals vary not only in terms of factors that contribute to its occurrence and development, but as importantly, in their capacity to respond to treatment. While exciting new therapeutic options that mobilize the immune system against cancer have led to breakthroughs for a variety of malignancies, success is limited to a subset of patients. Pre-existing immunological features of both the host and the tumor may contribute to how patients will eventually fare with immunotherapy. A broad understanding of baseline immunity, both in the periphery and in the tumor microenvironment, is needed in order to fully realize the potential of cancer immunotherapy. Such interrogation of the tumor, blood, and host immune parameters prior to treatment is expected to identify biomarkers predictive of clinical outcome as well as to elucidate why some patients fail to respond to immunotherapy. To approach these opportunities for progress, the Society for Immunotherapy of Cancer (SITC) reconvened the Immune Biomarkers Task Force. Comprised of an international multidisciplinary panel of experts, Working Group 4 sought to make recommendations that focus on the complexity of the tumor microenvironment, with its diversity of immune genes, proteins, cells, and pathways naturally present at baseline and in circulation, and novel tools to aid in such broad analyses.

Mixed hepatocellular cholangiocarcinoma tumors: Cholangiolocellular carcinoma is a distinct molecular entity

BACKGROUND & AIMS

Mixed hepatocellular cholangiocarcinoma (HCC-CCA) is a rare and poorly understood type of primary liver cancer. We aimed to perform a comprehensive molecular characterization of this malignancy.

METHODS

Gene expression profiling, DNA copy number detection, and exome sequencing using formalin-fixed samples from 18 patients with mixed HCC-CCA were performed, encompassing the whole histological spectrum of the disease. Comparative genomic analysis was carried out, using independent datasets of HCC (n=164) and intrahepatic cholangiocarcinoma (iCCA) (n=149).

RESULTS

Integrative genomic analysis of HCC-CCAs revealed that cholangiolocellular carcinoma (CLC) represents a distinct biliary-derived entity compared with the stem-cell and classical types. CLC tumors were neural cell adhesion molecule (NCAM) positive (6/6 vs. 1/12, p<0.001), chromosomally stable (mean chromosomal aberrations 5.7 vs. 14.1, p=0.008), showed significant upregulation of transforming growth factor (TGF)-β signaling and enrichment of inflammation-related and immune response signatures (p<0.001). Stem-cell tumors were characterized by spalt-like transcription factor 4 (SALL4) positivity (6/8 vs. 0/10, p<0.001), enrichment of progenitor-like signatures, activation of specific oncogenic pathways (i.e., MYC and insulin-like growth factor [IGF]), and signatures related to poor clinical outcome. In the classical type, there was a significant correlation in the copy number variation of the iCCA and HCC components, suggesting a clonal origin. Exome sequencing revealed an average of 63 non-synonymous mutations per tumor (2 mean driver mutations per tumor). Among those, TP53 was the most frequently mutated gene (6/21, 29%) in HCC-CCAs.

CONCLUSIONS

Mixed HCC-CCA represents a heterogeneous group of tumors, with the stem-cell type characterized by features of poor prognosis, and the classical type with common lineage for HCC and iCCA components. CLC stands alone as a distinct biliary-derived entity associated with chromosomal stability and active TGF-β signaling.

LAY SUMMARY

Molecular analysis of mixed hepatocellular cholangiocarcinoma (HCC-CCA) showed that cholangiolocellular carcinoma (CLC) is distinct and biliary in origin. It has none of the traits of hepatocellular carcinoma (HCC). However, within mixed HCC-CCA, stem-cell type tumors shared an aggressive nature and poor outcome, whereas the classic type showed a common cell lineage for both the HCC and the intrahepatic CCA component. The pathological classification of mixed HCC-CCA should be redefined because of the new molecular data provided.

CCR6+ B lymphocytes responding to tumor cell-derived CCL20 support hepatocellular carcinoma progression via enhancing angiogenesis

BACKGROUND & AIMS

Different immune cells in tumor microenvironment shape tumor progression. CCL20 over-expression was reported as one of the "stemness" trait in TP53 mutated hepatocellular carcinoma (HCC). We aimed to understand the effect of CCL20 on HCC progression.

METHODS

In two HCC cohort patients (n=95, n=85 respectively), serum CCL20 concentration was quantified by using ELISA. Expressions of CCL20 and CCR6 in 41 paired HCC tumor and adjacent non-tumor tissues were determined by quantitative Real-Time PCR, confirmed by immunohistochemistry (CCL20) or by flow cytometry analysis (CCR6). Chemotaxis of splenocytes or purified CD19⁺ B cells to tumor cell-derived CCL20, and angiogenesis of different CD19⁺ B subtypes responding to tumor cell-derived CCL20 were measured in vitro. H22 murine hepatoma cells were inoculated into immunocompetent or immunodeficient SCID mice, tumor growth and metastasis were monitored after the mice were treated with anti-CCL20 neutralizing antibody or depleted B cells by anti-CD20.

RESULTS

Elevation of pretherapy serum CCL20 in HCC patients and increase of CCR6 expression in HCC tissues were closely associated with tumor metastasis and disease poor prognosis. In HCC tissues, CCL20 expression was positively correlated with CCR6 (R² =0.3134, P=0.0002), and CCR6 was exclusively identified in tumor infiltrated immune cells. CD19⁺CD5⁺ B lymphocytes expressed higher CCR6, responded to tumor cell-derived CCL20 and enhanced angiogenesis in vitro. Neutralizing CCL20 activity in immunocompetent mice, not in SCID mice, attenuated tumor incidence, restrained tumor growth and distal metastasis. Tumor angiogenesis was significantly inhibited after CCL20 activity was blockade. In addition, inhibiting B lymphocyte infiltration into tumor mileum also attenuated tumor growth.

CONCLUSIONS

Tumor cell-derived CCL20 interacts with CCR6 highly expressed CD19⁺CD5⁺ B cells, to promote HCC progression, which might be via enhancing angiogenesis.

Prognostic Biomarker Identification Through Integrating the Gene Signatures of Hepatocellular Carcinoma Properties

Many molecular classification and prognostic gene signatures for hepatocellular carcinoma (HCC) patients have been established based on genome-wide gene expression profiling; however, their generalizability is unclear. Herein, we systematically assessed the prognostic effects of these gene signatures and identified valuable prognostic biomarkers by integrating these gene signatures. With two independent HCC datasets (GSE14520, N = 242 and GSE54236, N = 78), 30 published gene signatures were evaluated, and 11 were significantly associated with the overall survival (OS) of postoperative HCC patients in both datasets. The random survival forest models suggested that the gene signatures were superior to clinical characteristics for predicting the prognosis of the patients. Based on the 11 gene signatures, a functional protein-protein interaction (PPI) network with 1406 nodes and 10,135 edges was established. With tissue microarrays of HCC patients (N = 60), we determined the prognostic values of the core genes in the network and found that RAD21, CDK1, and HDAC2 expression levels were negatively associated with OS for HCC patients. The multivariate Cox regression analyses suggested that CDK1 was an independent prognostic factor, which was validated in an independent case cohort (N = 78). In cellular models, inhibition of CDK1 by siRNA or a specific inhibitor, RO-3306, reduced cellular proliferation and viability for HCC cells. These results suggest that the prognostic predictive capacities of these gene signatures are reproducible and that CDK1 is a potential prognostic biomarker or therapeutic target for HCC patients.

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Eleven gene signatures have promising values for the OS prediction of HCC patients who undergo the surgical treatments.

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Prediction results for the 11 gene signatures were in moderate concordance, and genes included were functionally linked.

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CDK1 is an independent prognostic biomarker and a potential therapeutic target for HCC patients.

Various gene signatures for hepatocellular carcinoma (HCC) patients have been reported; however, their generalizability is unclear. Using two HCC patient datasets, we assessed the prognostic values of these gene signatures and identified 11 gene signatures that were associated with overall survival for postoperative HCC patients in both cohorts. Genes derived from these signatures formed a functional protein-protein interaction network with 1,406 nodes and 10,135 edges, and the expression levels of three core genes, RAD21, CDK1, and HDAC2, in the network were negatively associated with the overall survival of HCC patients. Further studies suggested that CDK1 is an independent prognostic factor and that it is a potential therapeutic target for HCC patients.

Tumor regulation of the tissue environment in the liver

The tumor microenvironment (TME) in the liver plays an important role in primary and metastatic liver tumor formation and tumor growth promotion. Cellular and non-cellular components of the TME significantly influence tumor development, growth, metastatic spread, anti-tumor immunity and response to tumor therapy. The cellular components of the TME in the liver not only consist of infiltrating immune cells, but also of liver-resident cells such as liver sinusoidal endothelial cells (LSEC) and hepatic stellate cells (HSC), which promote tumor growth by negatively regulating tumor-associated immune responses. In this review, we characterize cells of the TME with pro- and anti-tumor function in primary and metastatic liver tumors. Furthermore, we summarize mechanisms that permit growth of hepatic tumors despite the occurrence of spontaneous anti-tumor immune responses and how novel therapeutic approaches targeting the TME could unleash tumor-specific immune responses to improve survival of liver cancer patients.

Interaction between tumour-infiltrating B cells and T cells controls the progression of hepatocellular carcinoma

OBJECTIVE

The nature of the tumour-infiltrating leucocytes (TILs) is known to impact clinical outcome in carcinomas, including hepatocellular carcinoma (HCC). However, the role of tumour-infiltrating B cells (TIBs) remains controversial. Here, we investigate the impact of TIBs and their interaction with T cells on HCC patient prognosis.

DESIGN

Tissue samples were obtained from 112 patients with HCC from Singapore, Hong Kong and Zurich and analysed using immunohistochemistry and immunofluorescence. RNA expression of CD19, CD8A, IFNG was analysed using quantitative PCR. The phenotype of freshly isolated TILs was analysed using flow cytometry. A mouse model depleted of mature B cells was used for functional study.

RESULTS

Tumour-infiltrating T cells and B cells were observed in close contact with each other and their densities are correlated with superior survival in patients with HCC. Furthermore, the density of TIBs was correlated with an enhanced expression of granzyme B and IFN-γ, as well as with reduced tumour viability defined by low expression of Ki-67, and an enhanced expression of activated caspase-3 on tumour cells. CD27 and CD40 costimulatory molecules and TILs expressing activation marker CD38 in the tumour were also correlated with patient survival. Mice depleted of mature B cells and transplanted with murine hepatoma cells showed reduced tumour control and decreased local T cell activation, further indicating the important role of B cells.

CONCLUSIONS

The close proximity of tumour-infiltrating T cells and B cells indicates a functional interaction between them that is linked to an enhanced local immune activation and contributes to better prognosis for patients with HCC.

Association of Lymphocyte-to-Monocyte Ratio With the Mortality in Patients With ST-Elevation Myocardial Infarction Who Underwent Primary Percutaneous Coronary Intervention

We investigated whether the lymphocyte-to-monocyte ratio (LMR) 48 hours after admission is related to 30-day and long-term mortality in patients with ST-elevation myocardial infarction (STEMI) who were treated with primary percutaneous coronary intervention (PCI). We evaluated 318 consecutive patients with STEMI who were undergoing primary PCI. The relationship between the LMR_48h and all-cause mortality (30-day and long-term) was analyzed by categorizing the patients into tertiles (T) according to LMR_48h-T1 (>2.46), T2 (1.67-2.46), and T3 (<1.67). The T3 group exhibited the highest risk of 30-day all-cause mortality (hazard ratio [HR]: 8.093 [1.006-65.074]; P = .049). For long-term mortality, a significantly higher mortality risk was observed in both T2 (HR: 2.005 [1.021-3.939]; P = .043) and T3 groups (HR: 2.374 [1.160-4.857]; P < .001) compared to the T1 group (reference group). In multivariate analysis, these associations remained unaltered even after adjusting for confounders. A low LMR at 48 hours after admission may be independently associated with both 30-day and long-term mortality in patients with STEMI who were treated with primary PCI. This marker may be used for identifying patients with STEMI at high risk.

Role of Monocyte Count and Neutrophil-to-Lymphocyte Ratio in Survival of Oral Cancer Patients

Introduction Inflammation seems to play a critical role in the development and progression of numerous cancers. Peripheral blood leukocyte count is an easily assessable parameter of systemic inflammatory response. Objective The aim of this study was to investigate whether the pretreatment leukocyte counts can predict the prognosis of patients with oral cavity cancer. Methods Medical records of 471 oral cavity cancer patients diagnosed between January 2007 and December 2008 were retrospectively analyzed. Receiver operating characteristic curve analysis and Cox proportional hazards analyses were applied to evaluate the associations of leukocyte counts with overall survival. Results The overall five year's survival of the cohort was found to be 49.4%. On univariate analysis, elevated monocyte count (≥500/mm3) and neutrophil-to-lymphocyte ratio (NLR) (>2.38) were associated with poor overall survival (OS) (p = 0.001 and 0.000, respectively). Multivariate Cox proportional hazard analysis showed that higher monocyte and NLR levels were significant independent predictors of worse OS (HR = 1.385, 95% CI = 1.049 - 1.829; p < 0.05 and HR = 1.392, 95% CI = 1.045 - 1.855; p < 0.05, respectively). The advanced overall stage and lymph nodal involvement were also independent indicators for poor OS. Conclusions Higher pretreatment monocyte and NLR levels are independent predictors of poor prognosis for patients with oral cavity cancer. Thus, these easily accessed variables can serve as a potent marker to predict the outcomes of oral cancer patients.

High NKG2A expression contributes to NK cell exhaustion and predicts a poor prognosis of patients with liver cancer

Background and Aims: As the predominant lymphocyte subset in the liver, natural killer (NK) cells have been shown to be highly associated with the outcomes of patients with chronic hepatitis B virus infection (CHB) and hepatocellular carcinoma (HCC). Previously, we reported that NKG2A, a checkpoint candidate, mediates human and murine NK cell dysfunction in CHB. However, NK cell exhaustion and, particularly, the level of NKG2A expression within liver tumors have not been reported. Methods: In this study, we analyzed NKG2A expression and the related dysfunction of NK cells located in intra- or peritumor regions of liver tissue samples from 207 HCC patients, in addition to analyzing disease outcomes. Results: The expression of NKG2A in NK cells and the NKG2A ligand, HLA-E, in intratumor HCC tissues was observed to be increased. These NK cells, and particularly CD56^dim NK cells, with higher NKG2A expression showed features of functional exhaustion and were associated with a poor prognosis. The increase in NKG2A expression might be induced by IL-10, which was present at a high level in the plasma of HCC patients. Blocking IL-10 could specifically inhibit NKG2A expression in NK cells. Conclusions: These findings indicate that NKG2A expression is influenced by factors from cancer nests and contributes to NK cell exhaustion, suggesting that NKG2A blockade has the potential to restore immunity against liver tumors by reversing NK cell exhaustion.

Phenotype and function of CXCR5+CD45RA-CD4+ T cells were altered in HBV-related hepatocellular carcinoma and elevated serum CXCL13 predicted better prognosis

The present study reveals an immunological characterization of circulating and tumor-infiltrating T follicular helper cells (Tfh), namely CXCR5⁺CD45RA⁻CD4⁺ T cells, and their related cytokines in hepatitis B virus-related hepatocellular carcinoma (HCC) patients. In HCC patients, circulating Tfh cells showed a CCR7⁺ and/or ICOS⁺ phenotype with increased Th2-like cells and decreased Th1-like and Th17-like subsets. Although the bulk frequency of circulating Tfh cells was not altered in HCC patients, the frequency of infiltrated CXCR5⁺CD45RA⁻CD4⁺ CD3⁺cells was higher in tumor than in para-tumor tissues, and Th1-like cells were the predominant phenotype. Circulating Tfh cells in HCC patients were defective in the production of IL-21 in vitro, which was in accordance with lower IL-21 levels in tumor tissues than in para-tumor tissues. Serum CXCL13 was increased in HCC patients and associated with recurrence-free survival after hepatectomy. This was confirmed in an additional HCC cohort of 111 patients with up to 5 years follow-up. Immunohistochemical staining indicated that the percentage of CXCR5⁺ or CXCL13⁺ cells was higher in poorly differentiated than in well-differentiated tumors. In conclusion, patients with HBV-related HCC showed altered phenotypes and impaired function of Tfh cells or subpopulations. CXCL13 could be a potential biomarker for predicting recurrence in HCC patients after hepatectomy.

Programmed death ligand 1 as an indicator of pre-existing adaptive immune responses in human hepatocellular carcinoma

It is well known that the aberrant expression of programmed death ligand 1 (PD-L1) on tumor cells impairs antitumor immunity. To date, in hepatocellular carcinoma (HCC), the relationship between PD-L1 expression and host-tumor immunity is not well defined. Here, the expression levels of PD-L1 and CD8(+) T cell infiltration were analyzed by immunohistochemistry (IHC) in formalin fixed paraffin embedded (FFPE) specimens from 167 HCC patients undergoing resection. A significant positive association was found between PD-L1 expression and the presence of CD8(+) T cell (p < 0.0001). Moreover, constitutive PD-L1 protein expression was not detected by western blot in HepG2, Hep3B, and 7402 HCC cancer cell lines; but co-cultured these cell lines with INFγ, a cytokine produced by activated CD8(+) T cells, remarkably upregulated PD-L1 expression. In fresh frozen HCC specimens, INFγ was found to be significantly correlated with PD-L1 and CD8(+) gene expression, as evaluated by quantitative reverse transcriptase polymerase chain reaction (RT-PCR). These findings indicate that increased PD-L1 level may represent an adaptive immune resistance mechanism exerted by tumor cells in response to endogenous antitumor activity. Both increased intratumoral PD-L1 and CD8(+) were significantly associated with superior DFS (CD8(+): p = 0.03; PD-L1: p = 0.023) and OS (CD8(+): p = 0.001 and PD-L1: p = 0.059), but PD-L1 expression was not independently prognostic. In conclusions, PD-L1 upregulation is mainly induced by activated CD8(+) cytotoxic T cells pre-existing in HCC milieu rather than be constitutively expressed by the tumor cells, and it is a favorable prognostic factor for HCC.

TLR3 agonist and Sorafenib combinatorial therapy promotes immune activation and controls hepatocellular carcinoma progression

Hepatocellular carcinoma (HCC) is associated with high mortality and the current therapy for advanced HCC, Sorafenib, offers limited survival benefits. Here we assessed whether combining the TLR3 agonist: lysine-stabilized polyinosinic-polycytidylic-acid (poly-ICLC) with Sorafenib could enhance tumor control in HCC. Combinatorial therapy with poly-ICLC and Sorafenib increased apoptosis and reduced proliferation of HCC cell lines in vitro, in association with impaired phosphorylation of AKT, MEK and ERK. In vivo, the combinatorial treatment enhanced control of tumor growth in two mouse models: one transplanted with Hepa 1-6 cells, and the other with liver tumors induced using the Sleeping beauty transposon. Tumor cell apoptosis and host immune responses in the tumor microenvironment were enhanced. Particularly, the activation of local NK cells, T cells, macrophages and dendritic cells was enhanced. Decreased expression of the inhibitory signaling molecules PD-1 and PD-L1 was observed in tumor-infiltrating CD8⁺ T cells and tumor cells, respectively. Tumor infiltration by monocytic-myeloid derived suppressor cells (Mo-MDSC) was also reduced indicating the reversion of the immunosuppressive tumor microenvironment. Our data demonstrated that the combinatorial therapy with poly-ICLC and Sorafenib enhances tumor control and local immune response hence providing a rationale for future clinical studies.

Local production of the chemokines CCL5 and CXCL10 attracts CD8+ T lymphocytes into esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a very common malignant tumor with poor prognosis in China. Chemokines secreted by tumors are pivotal for the accumulation of CD8(+) T lymphocytes within malignant lesions in several types of cancers, but the exact mechanism underlying CD8(+) T lymphocyte homing is still unknown in ESCC. In this study, we revealed that, compared with marginal tissues, the expression of both chemokine (C-C motif) ligand 5 (CCL5) and (C-X-C motif) ligand 10 (CXCL10) was upregulated in ESCC tissues. CCL5 expression was positively associated with the overall survival of patients. Meanwhile, RT-PCR data showed that the expression of CCL5 and CXCL10 was positively correlated with the local expressions of the CD8(+) T lymphocyte markers (CD8 and Granzyme B) in tumor tissues. Correspondingly, CD8(+) T lymphocytes were more frequently CCR5- and CXCR3-positive in tumor than in peripheral blood. Transwell analysis showed both CCL5 and CXCL10 were important for the chemotactic movement of CD8(+) T lymphocytes. Our data indicate that CCL5 and CXCL10 serve as the key chemokines to recruit CD8(+) T lymphocytes into ESCC tissue and may play a role in patient survival.

The Relationship Between Lymphocyte-to-Monocyte Ratio and Bare-Metal Stent In-Stent Restenosis in Patients With Stable Coronary Artery Disease

In-stent restenosis (ISR) is a common clinical problem in patients with coronary artery disease treated with percutaneous coronary intervention. Inflammatory process plays a pivotal role in the development of ISR. Both lymphocytes and monocytes are associated with inflammatory status. Recently, it has been shown that the lymphocyte-to-monocyte ratio (LMR) is a novel inflammatory marker. We aimed to investigate the association of serum LMR levels and ISR in patients undergoing bare-metal stent (BMS) implantation. The study included 273 patients (aged 61 ± 11 years, 66.5% men) with a history of BMS implantation and a further control coronary angiography due to stable angina pectoris. Patients were divided into 2 groups: patients with and without ISR. The LMR levels were significantly lower in patients with ISR than in those without ISR (2.50 ± 0.95 vs 3.87 ± 1.51, respectively, P < .001). On multivariate logistic regression analysis, the LMR was independently associated with ISR (odds ratio [OR]: 0.310, 95% confidence interval: 0.166-0.579, P < .001) together with high-sensitivity C-reactive protein (OR: 1.244, P = .008), reason for stent implantation (OR: 6.566, P = .003), stent diameter (OR: 0.015, P < .001), and stent length (OR: 1.137, P = .007). In conclusion, LMR levels are inversely related to ISR in patients treated with BMS implantation.