Immunobiology of hepatocarcinogenesis: Ways to go or almost there?

Key oncogenic signaling pathways affecting tumor-infiltrating lymphocytes infiltration in hepatocellular carcinoma: basic principles and recent advances

The incidence of hepatocellular carcinoma (HCC) ranks first among primary liver cancers, and its mortality rate exhibits a consistent annual increase. The treatment of HCC has witnessed a significant surge in recent years, with the emergence of targeted immune therapy as an adjunct to early surgical resection. Adoptive cell therapy (ACT) using tumor-infiltrating lymphocytes (TIL) has shown promising results in other types of solid tumors. This article aims to provide a comprehensive overview of the intricate interactions between different types of TILs and their impact on HCC, elucidate strategies for targeting neoantigens through TILs, and address the challenges encountered in TIL therapies along with potential solutions. Furthermore, this article specifically examines the impact of oncogenic signaling pathways activation within the HCC tumor microenvironment on the infiltration dynamics of TILs. Additionally, a concise overview is provided regarding TIL preparation techniques and an update on clinical trials investigating TIL-based immunotherapy in solid tumors.

Identification of the ferroptosis-related ceRNA network related to prognosis and tumor immunity for gastric cancer

Gastric cancer (GC) is a highly invasive course and has a very poor prognosis. Because there are no obvious symptoms in the early stage, most patients with GC are diagnosed in the late stage. The effective diagnosis, prognosis biomarkers and treatment targets of GC can solve this problem to a great extent. Although researchers have done a lot of research on GC in recent years, the relationship between the competing endogenous RNA (ceRNA) network of ferroptosis-related genes and the GC remains to be explored. Therefore, the research done in this paper has become particularly important. Download the expression data and clinical survival data about stomach adenocarcinoma from UCSC Xena and The Cancer Genome Atlas (TCGA) platform. Using bioinformatics tools to screen lncRNAs, miRNAs and mRNAs that are differentially expressed in GC samples and normal samples and related to the prognosis of GC. Then, screening lncRNAs, miRNAs and mRNAs with targeted relationships from the Starbase database. Subsequently, correlation analysis and survival analysis were carried out respectively. Finally, we get a ceRNA network related to the prognosis of GC patients. Cell experiments confirmed the results obtained by bioinformatics. This is critical for the discovery of the diagnosis, prognosis biomarkers and treatment targets.

Immunotherapy in liver transplantation for hepatocellular carcinoma: Pros and cons

Liver transplantation (LT) has emerged as a curative strategy for hepatocellular carcinoma (HCC), but contributes to a higher predisposition to HCC recurrence in the immunosuppression context, especially for tumors beyond the Milan criteria. Although immunotherapy has dramatically improved survival for immunocompetent patients and has become the standard of care for a variety of tumors, including HCC, it is mainly used outside the scope of organ transplantation owing to potentially fatal allograft rejection. Nevertheless, accumulative evidence has expanded the therapeutic paradigms of immunotherapy for HCC, from downstaging or bridging management in the pretransplant setting to the salvage or adjuvant strategy in the posttransplant setting. Generally, immunotherapy mainly includes immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT) and vaccine therapy. ICIs, followed by ACT, have been most investigated in LT, with some promising results. Because of the complex tumor microenvironment and immunoreactivity when immunosuppressants are combined with immunotherapy, it is difficult to reach formulations for immunosuppressant adjustment and the optimal selection of immunotherapy as well as patients. In addition, the absence of effective biomarkers for identifying rejection and tumor response is still an unresolved barrier to successful clinical immunotherapy applications for LT. In this review, we comprehensively summarize the available evidence of immunotherapy used in LT that is specific to HCC. Moreover, we discuss clinically concerning issues regarding the concurrent goals of graft protection and antitumor response.

Characterization of the inflammatory microenvironment and hepatic macrophage subsets in experimental hepatocellular carcinoma models

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. HCC typically develops on a background of chronic inflammation and fibrosis with tumor associated macrophages (TAMs) playing an important role in chronic inflammation-induced HCC and progression. However, the liver harbors unique macrophages, resident liver Kupffer cells (KCs) and monocyte-derived macrophages (Mo-Mφ), and their contribution to HCC and to the population of TAMs is incompletely known. Here, we characterized the tumor microenvironment and the proportion and transcriptional profile of hepatic macrophages (Mφ) in two commonly used HCC mouse models. A gradually increased expression of inflammatory, immune regulatory, fibrotic and cell proliferation pathways and markers was observed during diethylnitrosamine (DEN)- and non-alcoholic steatohepatitis (NASH)-induced HCC development. The transcriptional phenotypes of isolated hepatic Mφ subsets were clearly distinct and shifted during HCC development, with mixed pro-inflammatory and tumor-promoting expression profiles. There were marked differences between the models as well, with Mφ in NASH-HCC exhibiting a more immunomodulatory phenotype, in conjunction with an upregulation of lipid metabolism genes. Our data show that at least some infiltrated macrophages display expression of pro-tumoral markers, and that Kupffer cells are part of the population of TAMs and enhance tumor progression. These insights are useful to further unravel sequential pathogenic events during hepatocarcinogenesis and direct future development of new treatment strategies for HCC.

Construction and Validation of a Ferroptosis-Related Prognostic Model for Gastric Cancer

BACKGROUND

Gastric cancer (GC), an extremely aggressive tumor with a very different prognosis, is the third leading cause of cancer-related mortality. We aimed to construct a ferroptosis-related prognostic model that can be distinguished prognostically.

METHODS

The gene expression and the clinical data of GC patients were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database (GEO). The ferroptosis-related genes were obtained from the FerrDb. Using the "limma" R package and univariate Cox analysis, ferroptosis-related genes with differential expression and prognostic value were identified in the TCGA cohort. Last absolute shrinkage and selection operator (LASSO) Cox regression was applied to shrink ferroptosis-related predictors and construct a prognostic model. Functional enrichment, ESTIMATE algorithm, and single-sample gene set enrichment analysis (ssGSEA) were applied for exploring the potential mechanism. GC patients from the GEO cohort were used for validation.

RESULTS

An 8-gene prognostic model was constructed and stratified GC patients from TCGA and meta-GEO cohort into high-risk groups or low-risk groups. GC patients in high-risk groups have significantly poorer OS compared with those in low-risk groups. The risk score was identified as an independent predictor for OS. Functional analysis revealed that the risk score was mainly associated with the biological function of extracellular matrix (ECM) organization and tumor immunity.

CONCLUSION

In conclusion, the ferroptosis-related model can be utilized for the clinical prognostic prediction in GC.

The Profile and Role of Tumor-infiltrating Lymphocytes in Hepatocellular Carcinoma: An Immunohistochemical Study

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver. Tumor-infiltrating lymphocytes (TILs) are a class of cells that form the tumor microenvironment and thus have an effect on carcinogenesis. The aim of this study was to investigate the immunohistochemical expression of CD8, CD4, cytotoxic T lymphocyte-associated protein-4 (CTLA-4), and granzyme B in HCC and their correlation with clinicopathologic parameters and prognosis. This study was carried out on 112 cases of HCC. High percentage of CD8+ TILs was associated with large tumors and adjacent noncirrhotic liver. High percentage of CD4+ TILs and high CD4 to CD8 ratio were associated with nonviral etiology, low alpha fetoprotein, and direct acting antiviral treatment. High percentage of CTLA-4-positive TILs tended to be associated with high-grade HCC, while a high percentage of CTLA-4 in tumor cells was associated with multiple lesions and low tumor grade. High percentage of granzyme B+ TILs was associated with low grade, early stage, and absence of tumor recurrence. High CD4 percentage and high CD4/CD8 ratio affected patients' overall survival. There is a dynamic interaction between the different subsets of lymphocytes in the environment of HCC manifested by coparallel expression of CD4 and CD8 augmenting the expression of CTLA-4, and only CD8 augments the expression of granzyme B. This opens the gate for the beneficial role of immunotherapy in the management of HCC, reducing recurrence and improving survival.

Modulating the Crosstalk between the Tumor and Its Microenvironment Using RNA Interference: A Treatment Strategy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with one of the highest mortality rates among solid cancers. It develops almost exclusively in the background of chronic liver inflammation, which can be caused by viral hepatitis, chronic alcohol consumption or an unhealthy diet. Chronic inflammation deregulates the innate and adaptive immune responses that contribute to the proliferation, survival and migration of tumor cells. The continuous communication between the tumor and its microenvironment components serves as the overriding force of the tumor against the body's defenses. The importance of this crosstalk between the tumor microenvironment and immune cells in the process of hepatocarcinogenesis has been shown, and therapeutic strategies modulating this communication have improved the outcomes of patients with liver cancer. To target this communication, an RNA interference (RNAi)-based approach can be used, an innovative and promising strategy that can disrupt the crosstalk at the transcriptomic level. Moreover, RNAi offers the advantage of specificity in comparison to the treatments currently used for HCC in clinics. In this review, we will provide the recent data pertaining to the modulation of a tumor and its microenvironment by using RNAi and its potential for therapeutic intervention in HCC.

Management and Treatment of Hepatocellular Carcinoma with Immunotherapy: A Review of Current and Future Options

With mortality rates of liver cancer doubling in the last 20 years, this disease is on the rise and has become the fifth most common cancer in men and the seventh most common cancer in women. Hepatocellular carcinoma (HCC) represents approximately 90% of all primary liver cancers and is a major global health concern. Patients with HCC can be managed curatively with surgical resection or with liver transplantation, if they are diagnosed at an early stage. Unfortunately, most patients with HCC present with advanced stages of the disease and have underlying liver dysfunction, which allows only 15% of patients to be eligible for curative treatment. Several different treatment modalities are available, including locoregional therapy radiofrequency ablation, microwave ablation, percutaneous ethanol injection, trans-arterial chemoembolization, transarterial radio-embolization, cryoablation, radiation therapy, stereotactic radiotherapy, systemic chemotherapy, molecularly targeted therapies, and immunotherapy. Immunotherapy has recently become a promising method for inhibiting HCC tumor progression, recurrence, and metastasis. The term "Immunotherapy" is a catch-all, encompassing a wide range of applications and targets, including HCC vaccines, adoptive cell therapy, immune checkpoint inhibitors, and use of oncolytic viruses to treat HCC. Immunotherapy in HCC is a relatively safe option for treating patients with advanced disease in the USA who are either unable to receive or failed sorafenib/lenvatinib therapy and thus may offer an additional survival benefit for these patients. The purpose of this review is to elaborate on some of the most recent advancements in immunotherapy.

The role of natural killer cells in hepatocellular carcinoma development and treatment: A narrative review

A major obstacle for treatment of HCC is the inadequate efficacy and limitation of the available therapeutic options. Despite the recent advances in developing novel treatment options, HCC still remains one of the major causes of cancer morbidity and mortality around the world. Achieving effective treatment and eradication of HCC is a challenging task, however recent studies have shown that targeting Natural Killer cells, as major regulators of immune system, can help with the complete treatment of HCC, restoration of normal liver function and subsequently higher survival rate of HCC patients. Studies have shown that decrease in the frequency of NK cells, their dysfunction due to several factors such as dysregulation of receptors and their ligands, and imbalance of different types of inhibitory and stimulating microRNA expression is associated with higher rate of HCC progression and development, and poor survival outcome. Here in our review, we mainly focused on the importance of NK cells in HCC development and treatment.

Preclinical and Clinical Therapeutic Strategies Affecting Tumor-Associated Macrophages in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) most often develops in patients with underlying liver disease characterized by chronic nonresolving inflammation. Tumor-associated macrophages (TAMs) are one of the most abundant immune cell populations within the tumoral microenvironment. As key actors of cancer-related inflammation, they promote tumor growth by suppression of effective anticancer immunity, stimulation of angiogenesis, and tissue remodeling. Therefore, they have become an attractive and promising target for immunotherapy. The heterogeneity of TAM subtypes and their origin and dynamic phenotype during the initiation and progression of HCC has been partially unraveled and forms the base for the development of therapeutic agents. Current approaches are aimed at decreasing the population of TAMs by depleting macrophages present in the tumor, blocking the recruitment of bone marrow-derived monocytes, and/or functionally reprogramming TAMs to antitumoral behavior. In this review, the preclinical evolution and hitherto clinical trials for TAM-targeted therapy in HCC will be highlighted.

Immunoregulatory Role of NK Cells in Tissue Inflammation and Regeneration

NK cells represent an important first line of defense against viral infection and cancer and are also involved in tissue homeostasis. Studies of NK cell activation in the last decade have revealed that they are able to respond to the inflammatory stimuli evoked by tissue damage and contribute to both progression and resolution of diseases. Exacerbation of the inflammatory response through interactions between immune effector cells facilitates the progression of non-alcoholic fatty liver disease (NAFLD) into steatosis, cirrhosis, and hepatocellular carcinoma (HCC). When hepatic damage is incurred, macrophage activation is crucial for initiating cross talk with neighboring cells present in the liver, including hepatocytes and NK cells, and the importance of this interaction in shaping the immune response in liver disease is increasingly recognized. Inflicted structural damage can be in part regenerated via the process of self-limiting fibrosis, though persistent hepatic damage will lead to chronic fibrosis and loss of tissue organization and function. The cytotoxic activity of NK cells plays an important role in inducing hepatic stellate cell apoptosis and thus curtailing the progression of fibrosis. Alternatively, in some diseases, such as HCC, NK cells may become dysregulated, promoting an immunosuppressive state where tumors are able to escape immune surveillance. This review describes the current understanding of the contributions of NK cells to tissue inflammation and metabolic liver diseases and the ongoing effort to develop therapeutics that target the immunoregulatory function of NK cells.