Cryoablation combined with dual immune checkpoint blockade enhances antitumor efficacy in hepatocellular carcinoma model mice.

BACKGROUND: Cryoablation (Cryo) is a minimally invasive treatment for tumors. Cryo can activate the body's immune response, although it is typically weak. The immune response induced by Cryo in hepatocellular carcinoma (HCC) is poorly understood. PD-1 and CTLA-4 monoclonal antibodies are immune checkpoint inhibitors used in immunotherapy for tumors. The combined use of these antibodies with Cryo may enhance the immune effect. METHODS: A Balb/c mouse model of HCC was established and treated with Cryo, immune checkpoint blockade (ICB), or Cryo + ICB (combination therapy). The growth trend of right untreated tumors and survival time of mice were determined. The expression of apoptosis-related proteins was detected by Western blot (WB) assay. The percentages of immune cells and immunosuppressive cells were analyzed by flow cytometry. The numbers of infiltrating T lymphocytes were checked by immunohistochemistry, and the levels of T-cell-associated cytokines were detected by Quantitative real-time Polymerase Chain Reaction (qRT-PCR) assays and Enzyme-Linked Immunosorbent Assays (ELISA) assays. RESULTS: Cryo + ICB inhibited the growth of right untreated tumors, promoted tumor cell apoptosis, and prolonged the survival time of mice. Local T-cell infiltration in right tumor tissues increased after the combination therapy, while the number of immunosuppressive cells was significantly reduced. In addition, the combination therapy may induce the production of multiple Th1-type cytokines but reduce the production of Th2-type cytokines. CONCLUSIONS: Cryo can activate CD8+ and CD4+ T-cell immune responses. Cryo + ICB can relieve the immunosuppressive tumor microenvironment and shift the Th1/Th2 balance toward Th1 dominance, further enhancing the Cryo-induced T-cell immune response and resulting in a stronger antitumor immune response.

Estimating the key outcomes and hepatocellular carcinoma risk in patients in immune-tolerant phase of chronic hepatitis B virus infection: A systematic review and meta-analysis.

The question of whether patients in the immune-tolerant (IT) phase of chronic hepatitis B virus (HBV) infection should undergo antiviral therapy and determine the optimal regimen remains unclear. A comprehensive search of PubMed, Embase, MEDLINE, Cochrane Library, and Wanfang Data from inception to 5 December 2023, was conducted. Studies reporting on key outcomes such as HBV DNA undetectability, HBeAg loss or seroconversion, HBsAg loss or seroconversion, and hepatocellular carcinoma (HCC) incidence in patients in the IT phase of chronic HBV infection were included. In total, 23 studies were incorporated. Approximately 4% of patients in the IT phase achieved spontaneous HBeAg loss over 48 weeks of follow-up. Antiviral therapy demonstrated a favourable impact on HBV DNA negative conversion (Children: risk ratios [RR] = 6.83, 95% CI: 2.90-16.05; Adults: RR = 25.84, 95% CI: 6.47-103.31) and HBsAg loss rates (Children: RR = 9.49, 95% CI: 1.74-51.76; Adults: RR = 7.35, 95% CI: 1.41-38.27) for patients in the IT phase. Subgroup analysis revealed that in adult patients in the IT phase, interferon plus nucleos(t)ide analogues (NA)-treated patients exhibited a higher pooled rate of HBsAg loss or seroconversion than those treated with NA monotherapy (9% vs. 0%). Additionally, the pooled annual HCC incidence for patients in the IT phase was 3.03 cases per 1000 person-years (95% CI: 0.99-5.88). Adult patients in the IT phase had a significantly lower HCC incidence risk than HBeAg-positive indeterminate phase patients (RR = 0.46, 95% CI: 0.32-0.66), with no significant differences observed between IT and immune-active phases. Presently, there is insufficient evidence solely based on reducing the risk of HCC incidence, to recommend treating patients in the IT phase of chronic HBV infection. However, both adult and paediatric patients in the IT phase responded well to antiviral therapy, showing favourable rates of HBsAg loss or seroconversion.

Construction and validation of prognostic signature for transcription factors regulating T cell exhaustion in hepatocellular carcinoma.

In the tumor microenvironment (TME), CD8+ T cells showed stage exhaustion due to the continuous stimulation of tumor antigens. To evaluate the status of CD8+ T cells and reverse the exhaustion is the key to evaluate the prognosis and therapeutic effect of tumor patients. The aim of this study was to establish a prognostic signature that could effectively predict prognosis and response to immunotherapy in patients with hepatocellular carcinoma (HCC). We used univariate Cox analysis to obtain transcription factors associated with CD8+ T cell exhaustion from The Cancer Genome Atlas dataset. Then, the prognostic signature for transcription factors basic leucine zipper ATF-like transcription factor, Eomesodermin, and T-box protein 21 regulating T cell exhaustion was constructed using LASSO Cox regression. The relative expression levels of the mRNA of the 3 transcription factors were detected by reverse transcription-quantitative polymerase chain reaction in 23 pairs of HCC and paracancer tissues, and verified internally in The Cancer Genome Atlas dataset and externally in the International Cancer Genome Consortium dataset. Cox regression analysis showed that risk score was an independent prognostic variable. The overall survival of the high-risk group was significantly lower than that of the low-risk group. The low-risk group had higher immune scores, matrix scores, and ESTIMATE scores, and significantly increased expression levels of most immune checkpoint genes in the low-risk group. Therefore, patients with lower risk scores benefit more from immunotherapy. The combination of the 3 transcription factors can evaluate the exhaustion state of CD8+ T cells in the TME, laying a foundation for evaluating the TME and immunotherapy efficacy in patients with HCC.

Microproteins encoded by noncanonical ORFs are a major source of tumor-specific antigens in a liver cancer patient meta-cohort.

The expression of tumor-specific antigens during cancer progression can trigger an immune response against the tumor. Here, we investigate if microproteins encoded by noncanonical open reading frames (ncORFs) are a relevant source of tumor-specific antigens. We analyze RNA sequencing data from 117 hepatocellular carcinoma (HCC) tumors and matched healthy tissue together with ribosome profiling and immunopeptidomics data. Combining human leukocyte antigen-epitope binding predictions and experimental validation experiments, we conclude that around 40% of the tumor-specific antigens in HCC are likely to be derived from ncORFs, including two peptides that can trigger an immune response in humanized mice. We identify a subset of 33 tumor-specific long noncoding RNAs expressing novel cancer antigens shared by more than 10% of the HCC samples analyzed, which, when combined, cover a large proportion of the patients. The results of the study open avenues for extending the range of anticancer vaccines.

SIGLEC15, negatively correlated with PD-L1 in HCC, could induce CD8+ T cell apoptosis to promote immune evasion.

Functional roles of SIGLEC15 in hepatocellular carcinoma (HCC) were not clear, which was recently found to be an immune inhibitor with similar structure of inhibitory B7 family members. SIGLEC15 expression in HCC was explored in public databases and further examined by PCR analysis. SIGLEC15 and PD-L1 expression patterns were examined in HCC samples through immunohistochemistry. SIGLEC15 expression was knocked-down or over-expressed in HCC cell lines, and CCK8 tests were used to examine cell proliferative ability in vitro. Influences of SIGLEC15 expression on tumor growth were examined in immune deficient and immunocompetent mice respectively. Co-culture system of HCC cell lines and Jurkat cells, flow cytometry analysis of tumor infiltrated immune cells and further sequencing analyses were performed to investigate how SIGLEC15 could affect T cells in vitro and in vivo. We found SIGLEC15 was increased in HCC tumor tissues and was negatively correlated with PD-L1 in HCC samples. In vitro and in vivo models demonstrated inhibition of SIGLEC15 did not directly influence tumor proliferation. However, SIGLEC15 could promoted HCC immune evasion in immune competent mouse models. Knock-out of Siglec15 could inhibit tumor growth and reinvigorate CD8+ T cell cytotoxicity. Anti-SIGLEC15 treatment could effectively inhibit tumor growth in mouse models with or without mononuclear phagocyte deletion. Bulk and single-cell RNA sequencing data of treated mouse tumors demonstrated SIGLEC15 could interfere CD8+ T cell viability and induce cell apoptosis. In all, SIGLEC15 was negatively correlated with PD-L1 in HCC and mainly promote HCC immune evasion through inhibition of CD8+ T cell viability and cytotoxicity.

Interleukin-10 as a marker for response to dendritic cells-dribbles immunotherapy in hepatocellular carcinoma, a mice model.

Cancer immunotherapy is a promising strategy in cancer management, including hepatocellular carcinoma (HCC). This experimental study aimed to evaluate interleukin-10 (IL-10) as a biomarker for monitoring the response of tumor-derived autophagosomes vaccine in inducing antitumor immunity in HCC induced mice. It was conducted on 56 BALB/c mice; divided into 20 normal and 36, cancer induced with human liver cancer cell line (HepG2) cells. The latter group was subdivided into a positive control group (n=6) and a treated group (n=30), that was subdivided into 3 subgroups: (A) treated with dendritic cells (DC) vaccine only, (B) treated with vaccine named Dribbles only, and (C) treated with DC plus Dribbles. Serum IL-10 was assessed after immunotherapy. The mean percentage of tumor volume reduction in mice vaccinated by DC plus Dribbles was significantly superior to DC and Dribbles groups (p= 0.013, and p= 0.043, respectively). There was a statistically significant difference in IL-10 levels between different immunotherapy groups (p= 0.0003). As the mean IL-10 level was 19.50 pg/ml for the positive control group, 13 pg/ml for Dribbles group, 10 pg/ml for DCs group and 3.50 pg/ml for DCs plus Dribbles group. We conclude that DC-Dribbles vaccine has a remarkable efficacy superior to either Dribbles alone or DC alone in the decline of HCC development and survival improvement. IL-10 is a predictive biomarker for response after immunotherapy.

Inflammatory Response in the Pathogenesis and Treatment of Hepatocellular Carcinoma: A Double-Edged Weapon.

Hepatocellular carcinoma (HCC) is the most frequent among primary liver tumors (90%) and one of the main causes of cancer-related death. It develops usually in a chronically inflamed environment, ranging from compensatory parenchymal regeneration to fibrosis and cirrhosis: carcinogenesis can potentially happen in each of these stages. Inflammation determined by chronic viral infection (hepatitis B, hepatitis C, and hepatitis delta viruses) represents an important risk factor for HCC etiology through both viral direct damage and immune-related mechanisms. The deregulation of the physiological liver immunological network determined by viral infection can lead to carcinogenesis. The recent introduction of immunotherapy as the gold-standard first-line treatment for HCC highlights the role of the immune system and inflammation as a double-edged weapon in both HCC carcinogenesis and treatment. In this review we highlight how the inflammation is the key for the hepatocarcinogenesis in viral, alcohol and metabolic liver diseases.

Advancements in Immunotherapeutic Treatments for Hepatocellular Carcinoma: Potential of Combination Therapies.

Hepatocellular carcinoma (HCC) is the sixth most prevalent cancer and a significant global health burden, with increasing incidence rates and limited treatment options. Immunotherapy has become a promising approach due to its ability to affect the immune microenvironment and promote antitumor responses. The immune microenvironment performs an essential role in both the progression and the development of HCC, with different characteristics based on specific immune cells and etiological factors. Immune checkpoint inhibitors, including programmed death-1/programmed death-ligand 1 inhibitors (pembrolizumab, nivolumab, and durvalumab) and cytotoxic T lymphocyte antigen-4 inhibitors (tremelimumab and ipilimumab), have the potential to treat advanced HCC and overcome adverse effects, such as liver failure and chemoresistance. Phase II and phase III clinical trials highlight the efficacy of pembrolizumab and nivolumab, respectively, in advanced HCC patients, as demonstrated by their positive effects on overall survival and progression-free survival. Tremelimumab has exhibited modest response rates, though it does possess antiviral activity. Thus, it is still being investigated in ongoing clinical trials. Combination therapies with multiple drugs have demonstrated potential benefits in terms of survival and tumor response rates, improving patient outcomes compared to monotherapy, especially for advanced-stage HCC. This review addresses the clinical trials of immunotherapies for early-, intermediate-, and advanced-stage HCC. Additionally, it highlights how combination therapy can significantly enhance overall survival, progression-free survival, and objective response rate in advanced-stage HCC, where treatment options are limited.

The Role of CD4+T Cells in Nonalcoholic Steatohepatitis and Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) has become the fourth leading cause of cancer-related deaths worldwide; annually, approximately 830,000 deaths related to liver cancer are diagnosed globally. Since early-stage HCC is clinically asymptomatic, traditional treatment modalities, including surgical ablation, are usually not applicable or result in recurrence. Immunotherapy, particularly immune checkpoint blockade (ICB), provides new hope for cancer therapy; however, immune evasion mechanisms counteract its efficiency. In addition to viral exposure and alcohol addiction, nonalcoholic steatohepatitis (NASH) has become a major cause of HCC. Owing to NASH-related aberrant T cell activation causing tissue damage that leads to impaired immune surveillance, NASH-associated HCC patients respond much less efficiently to ICB treatment than do patients with other etiologies. In addition, abnormal inflammation contributes to NASH progression and NASH-HCC transition, as well as to HCC immune evasion. Therefore, uncovering the detailed mechanism governing how NASH-associated immune cells contribute to NASH progression would benefit HCC prevention and improve HCC immunotherapy efficiency. In the following review, we focused our attention on summarizing the current knowledge of the role of CD4+T cells in NASH and HCC progression, and discuss potential therapeutic strategies involving the targeting of CD4+T cells for the treatment of NASH and HCC.

Effects of the subtypes of apolipoprotein E on immune inhibition and prognosis in patients with Hepatocellular Carcinoma.

PURPOSE: To investigate whether prognosis of patients with hepatocellular carcinoma (HCC) is affected by the abundance and subgroups of myeloid-derived suppressor cells (MDSCs) as well as subtypes and expression of apolipoprotein E (apoE). METHODS: 31 HCC patients were divided into three groups according to blood total apoE level for detecting the abundance of immunoregulatory cells by flow cytometry. Tumour tissue microarrays from 360 HCC patients were evaluated about the abundance and subgroups of MDSCs and the expression of apoE2, apoE3, apoE4 by immunofluorescence staining and immunohistochemistry staining. Survival analysis by means of univariate, multivariate COX regression and Kaplan-Meier methods of the 360 patients was performed based on clinical and pathological examinations along with 10 years' follow-up data. RESULTS: The lower apoE group presented higher abundance of MDSCs in the peripheral blood of HCC patients than higher apoE group. The abundance of monocyte-like MDSCs (M-MDSCs) was higher in the apoE low level group than high level group (p = 0.0399). Lower H-score of apoE2 (HR = 6.140, p = 0.00005) and higher H-score of apoE4 (HR = 7.001, p = 0.009) in tumour tissue were significantly associated with shorter overall survival (OS). The higher infiltration of polymorphonuclear granulocyte-like MDSCs (PMN-MDSCs, HR = 3.762, p = 0.000009) and smaller proportion of M-MDSCs of total cells (HR = 0.454, p = 0.006) in tumour tissue were independent risk factors for shorter recurrence-free survival (RFS). CONCLUSION: The abundance of MDSCs in HCC patients' plasma negatively correlates with the level of apoE. The expression of apoE4 in HCC tissue indicated a poor prognosis while apoE2 might be a potential protective factor.

A-to-I RNA co-editing predicts clinical outcomes and is associated with immune cells infiltration in hepatocellular carcinoma.

Aberrant RNA editing has emerged as a pivotal factor in the pathogenesis of hepatocellular carcinoma (HCC), but the impact of RNA co-editing within HCC remains underexplored. We used a multi-step algorithm to construct an RNA co-editing network in HCC, and found that HCC-related RNA editings are predominantly centralized within the network. Furthermore, five pairs of risk RNA co-editing events were significantly correlated with the overall survival in HCC. Based on presence of risk RNA co-editings resulted in the categorization of HCC patients into high-risk and low-risk groups. Disparities in immune cell infiltrations were observed between the two groups, with the high-risk group exhibiting a greater abundance of exhausted T cells. Additionally, seven genes associated with risk RNA co-editing pairs were identified, whose expression effectively differentiates HCC tumor samples from normal ones. Our research offers an innovative perspective on the etiology and potential therapeutics for HCC.

Emerging role of oncogenic ß-catenin in exosome biogenesis as a driver of immune escape in hepatocellular carcinoma.

Immune checkpoint inhibitors have produced encouraging results in cancer patients. However, the majority of ß-catenin-mutated tumors have been described as lacking immune infiltrates and resistant to immunotherapy. The mechanisms by which oncogenic ß-catenin affects immune surveillance remain unclear. Herein, we highlighted the involvement of ß-catenin in the regulation of the exosomal pathway and, by extension, in immune/cancer cell communication in hepatocellular carcinoma (HCC). We showed that mutated ß-catenin represses expression of SDC4 and RAB27A, two main actors in exosome biogenesis, in both liver cancer cell lines and HCC patient samples. Using nanoparticle tracking analysis and live-cell imaging, we further demonstrated that activated ß-catenin represses exosome release. Then, we demonstrated in 3D spheroid models that activation of ß-catenin promotes a decrease in immune cell infiltration through a defect in exosome secretion. Taken together, our results provide the first evidence that oncogenic ß-catenin plays a key role in exosome biogenesis. Our study gives new insight into the impact of ß-catenin mutations on tumor microenvironment remodeling, which could lead to the development of new strategies to enhance immunotherapeutic response.

Endoplasmic reticulum stress promotes hepatocellular carcinoma by modulating immunity: a study based on artificial neural networks and single-cell sequencing.

INTRODUCTION: Hepatocellular carcinoma (HCC) is characterized by the complex pathogenesis, limited therapeutic methods, and poor prognosis. Endoplasmic reticulum stress (ERS) plays an important role in the development of HCC, therefore, we still need further study of molecular mechanism of HCC and ERS for early diagnosis and promising treatment targets. METHOD: The GEO datasets (GSE25097, GSE62232, and GSE65372) were integrated to identify differentially expressed genes related to HCC (ERSRGs). Random Forest (RF) and Support Vector Machine (SVM) machine learning techniques were applied to screen ERSRGs associated with endoplasmic reticulum stress, and an artificial neural network (ANN) diagnostic prediction model was constructed. The ESTIMATE algorithm was utilized to analyze the correlation between ERSRGs and the immune microenvironment. The potential therapeutic agents for ERSRGs were explored using the Drug Signature Database (DSigDB). The immunological landscape of the ERSRGs central gene PPP1R16A was assessed through single-cell sequencing and cell communication, and its biological function was validated using cytological experiments. RESULTS: An ANN related to the ERS model was constructed based on SRPX, THBS4, CTH, PPP1R16A, CLGN, and THBS1. The area under the curve (AUC) of the model in the training set was 0.979, and the AUC values in three validation sets were 0.958, 0.936, and 0.970, respectively, indicating high reliability and effectiveness. Spearman correlation analysis suggests that the expression levels of ERSRGs are significantly correlated with immune cell infiltration and immune-related pathways, indicating their potential as important targets for immunotherapy. Mometasone was predicted to be the most promising treatment drug based on its highest binding score. Among the six ERSRGs, PPP1R16A had the highest mutation rate, predominantly copy number mutations, which may be the core gene of the ERSRGs model. Single-cell analysis and cell communication indicated that PPP1R16A is predominantly distributed in liver malignant parenchymal cells and may reshape the tumor microenvironment by enhancing macrophage migration inhibitory factor (MIF)/CD74 + CXCR4 signaling pathways. Functional experiments revealed that after siRNA knockdown, the expression of PPP1R16A was downregulated, which inhibited the proliferation, migration, and invasion capabilities of HCCLM3 and Hep3B cells in vitro. CONCLUSION: The consensus of various machine learning algorithms and artificial intelligence neural networks has established a novel predictive model for the diagnosis of liver cancer associated with ERS. This study offers a new direction for the diagnosis and treatment of HCC.

[Analysis of correlation between high expression of nucleoporin 85 (NUP85) and immune cell infiltration in hepatocellular carcinoma].

Objective To investigate the significance of nucleoporin 85 (NUP85) ex-pression in hepatocellular carcinoma (HCC) and analyze its relevance to immune response. Methods A comprehensive analysis was conducted using various online databases to assess the mRNA and protein expression of NUP85 in HCC, as well as its mutation status and prognostic diagnostic value. The immune relevance of NUP85 was evaluated using single-cell sequencing data and resources from the Tumor Immune Estimation Resource (TIMER) and the Gene Expression Profiling Interactive Analysis 2021 (GEPIA2021) databases. The drug sensitivity of NUP85 was analyzed through the Genomic Landscape of Cancer (GSCA) and the Clinical Bioinformatics Home. Co-expressed genes of NUP85 in HCC were filtered using the Hepatocellular Carcinoma Comprehensive Molecular Database (HCCDB), and the correlation between NUP85 and its related genes was analyzed using the R language "limma" package. The gene ontology (GO) functions, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) of NUP85 and its related genes were performed using the R language "clusterProfiler" package. The Clinical Bioinformatics Home was utilized to construct heatmaps and prognostic risk scoring models for NUP85 and its related genes. Results NUP85 mRNA and protein expression were upregulated in HCC, showing high levels across dif-ferent stages and grades, which indicates a poor prognosis for patients. The mutation rate of NUP85 in HCC samples was 19%, significantly affecting the overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS) of patients. NUP85 was highly expressed in various immune cells, including macrophages, B cells, and T cells, and was positively correlated with the infiltration levels of multiple immune cells. The expression of NUP85 was significantly correlated with multiple drugs, such as Milademetan (PD0325901), a structural analog of Vemurafenib (PLX4720), and Regorafenib (PD0325901). The GO functions of NUP85 and its co-expressed genes were mainly enriched in organelle fission, nuclear division, and chromosome segregation, while the KEGG pathways were primarily enriched in the cell cycle and kinesin proteins. These factors significantly and unfavorably affected the OS of HCC patients, and the areas under the ROC curve (AUC) for the 1-year, 3-year, and 5-year OS prognostic diagnosis of HCC patients were all greater than 0.7. Conclusion The high expression of NUP85 in HCC is correlated with a poor prognosis and is related to various immune cells and drugs, making it a potential biomarker for di-agnosis, treatment, and prognosis in HCC.

Immune landscape of hepatocellular carcinoma: From dysregulation of the immune responses to the potential immunotherapies.

Hepatocellular carcinoma (HCC) presents a considerable global health burden due to its late diagnosis and high morbidity. The liver's specific anatomical and physiological features expose it to various antigens, requiring precise immune regulation. To the best of our knowledge, this is the first time that a comprehensive overview of the interactions between the immune system and gut microbiota in the development of HCC, as well as the relevant therapeutic approaches are discussed. Dysregulation of immune compartments within the liver microenvironment drives HCC pathogenesis, characterized by elevated regulatory cells such as regulatory T cells (Tregs), myeloid-derived suppressor cells, and M2 macrophages as well as suppressive molecules, alongside reduced number of effector cells like T cells, natural killer cells, and M1 macrophages. Dysbiosis of gut microbiota also contributes to HCC by disrupting intestinal barrier integrity and triggering overactivated immune responses. Immunotherapy approaches, particularly immune checkpoint inhibitors, have exhibited promise in HCC management, yet adoptive cell therapy and cancer vaccination research are in the early steps with relatively less favorable outcomes. Further understanding of immune dysregulation, gut microbiota involvement, and therapeutic combination strategies are essential for advancing precision immunotherapy in HCC.

Mitotic catastrophe heterogeneity: implications for prognosis and immunotherapy in hepatocellular carcinoma.

Background and aims: The mitotic catastrophe (MC) pathway plays an important role in hepatocellular carcinoma (HCC) progression and tumor microenvironment (TME) regulation. However, the mechanisms linking MC heterogeneity to immune evasion and treatment response remain unclear. Methods: Based on 94 previously published highly correlated genes for MC, HCC patients' data from the Cancer Genome Atlas (TCGA) and changes in immune signatures and prognostic stratification were studied. Time and spatial-specific differences for MCGs were assessed by single-cell RNA sequencing and spatial transcriptome (ST) analysis. Multiple external databases (GEO, ICGC) were employed to construct an MC-related riskscore model. Results: Identification of two MC-related subtypes in HCC patients from TCGA, with clear differences in immune signatures and prognostic risk stratification. Spatial mapping further associates low MC tumor regions with significant immune escape-related signaling. Nomogram combining MC riskscore and traditional indicators was validated great effect for early prediction of HCC patient outcomes. Conclusion: MC heterogeneity enables immune escape and therapy resistance in HCC. The MC gene signature serves as a reliable prognostic indicator for liver cancer. By revealing clear immune and spatial heterogeneity of HCC, our integrated approach provides contextual therapeutic strategies for optimal clinical decision-making.

The significance of lipid metabolism reprogramming of tumor-associated macrophages in hepatocellular carcinoma.

In the intricate landscape of the tumor microenvironment, tumor-associated macrophages (TAMs) emerge as a ubiquitous cellular component that profoundly affects the oncogenic process. The microenvironment of hepatocellular carcinoma (HCC) is characterized by a pronounced infiltration of TAMs, underscoring their pivotal role in modulating the trajectory of the disease. Amidst the evolving therapeutic paradigms for HCC, the strategic reprogramming of metabolic pathways presents a promising avenue for intervention, garnering escalating interest within the scientific community. Previous investigations have predominantly focused on elucidating the mechanisms of metabolic reprogramming in cancer cells without paying sufficient attention to understanding how TAM metabolic reprogramming, particularly lipid metabolism, affects the progression of HCC. In this review article, we intend to elucidate how TAMs exert their regulatory effects via diverse pathways such as E2F1-E2F2-CPT2, LKB1-AMPK, and mTORC1-SREBP, and discuss correlations of TAMs with these processes and the characteristics of relevant pathways in HCC progression by consolidating various studies on TAM lipid uptake, storage, synthesis, and catabolism. It is our hope that our summary could delineate the impact of specific mechanisms underlying TAM lipid metabolic reprogramming on HCC progression and provide useful information for future research on HCC and the development of new treatment strategies.

Identification and characterization of RAC1-related immune and prognostic subtypes of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant tumor with significant variability in prognosis among patients. Ras-related C3 botulinum toxin substrate 1 (RAC1) is a key focus in the area of cancer research. However, the molecular mechanisms of RAC1 in HCC remain incompletely elucidated. MATERIALS AND METHODS: In this study, bioinformatics analysis was used, and public databases were used to obtain information about HCC cases. The samples were categorized into two groups of high and low expression based on the expression level of RAC1 gene. The limma package was used to calculate the differentially expressed genes between the two groups, and univariate Cox regression analysis was used to screen the prognostic related factors. Consensus clustering analysis was performed using the ConsensusClusterPlus package to identify molecular subtypes of HCC patients. Immune cell infiltration and ESTIMATE scores were assessed using the single sample gene set enrichment analysis and ESTIMATE algorithms. The sensitivity of different isoforms to chemotherapeutic agents was predicted by the oncoPredict package. Finally, we also performed cell function experiments to validate the biological role of RAC1 in vitro. Initially, we classified patients into high and low expression groups based on RAC1 gene expression levels and identified 195 up-regulated genes and 107 down-regulated genes. Through univariate Cox regression analysis, we screened out 169 prognosis-related factors. Furthermore, HCC patients were categorized into two subtypes. Subsequently, Kaplan-Meier survival curves showed that there was a significant difference in prognosis between the two molecular subtypes. Further analysis indicated substantial differences in gene expression levels and TIDE scores between two molecular subtypes. Moreover, these two subtypes exhibited varying sensitivity to chemotherapy drugs, as evidenced by differences in IC50 values. In addition, we found that the silence of RAC1 could effectively inhibit the migration and invasion of HCC cells in vitro. CONCLUSION: This study sheds light on the molecular intricacies of RAC1 in HCC and identifies patient populations that may benefit from immunotherapeutic interventions, with potential implications for tailored treatment strategies.

Single cell analyses reveal the PD-1 blockade response-related immune features in hepatocellular carcinoma.

Background: Immunotherapy has demonstrated its potential to improve the prognosis of patients with hepatocellular carcinoma (HCC); however, patients' responses to immunotherapy vary a lot. A comparative analysis of the tumor microenvironment (TME) in responders and non-responders is expected to unveil the mechanisms responsible for the immunotherapy resistance and provide potential treatment targets. Methods: We performed sequencing analyses using 10x Genomics technology on six HCC patients who responded to anti-PD-1 therapy and one HCC patient who did not respond. Additionally, we obtained single cell data from untreated, responsive, and nonresponsive HCC patients from public databases, and used part of the datasets as a validation cohort. These data were integrated using algorithms such as Harmony. An independent validation cohort was established. Furthermore, we performed spatial transcriptomic sequencing on the tumor adjacent tissues of three HCC responsive patients using 10x Genomics spatial transcriptomic technology. Additionally, we analyzed data about three HCC patients obtained from public databases. Finally, we validated our conclusions using immunofluorescence, flow cytometry, and in vivo experiments. Results: Our findings confirmed the presence of "immune barrier" partially accounting for the limited efficacy of immunotherapy. Our analysis revealed a significant increase in TREM2+ Macrophages among non-responsive patients expressing multiple immunosuppressive signals. anti-Csf1r monoclonal antibodies effectively eliminated these macrophages and augmented the therapeutic effects of anti-PD-1 therapy. TCR+ Macrophages possessed direct tumor-killing capabilities. IL1B+ cDC2 was the primary functional subtype of cDC2 cells. Absence of THEMIShi CD8+ T subtypes might diminish immunotherapeutic effects. Furthermore, CD8+ T cells entered a state of stress after anti-PD-1 treatment, which might be associated with CD8+ T cell exhaustion and senescence. Conclusions: The profiles of immune TMEs showed differences in HCC patients responsive, non-responsive and untreated. These differences might explain the discounted efficacy of immunotherapy in some HCC patients. The cells and molecules, which we found to carry unique capabilities, may be targeted to enhance immunotherapeutic outcomes in patients with HCC.

Efficacy comparison of immune combination therapies in subgroups for advanced hepatocellular carcinoma patients: Systematic review and network meta-analysis.

BACKGROUND: There is a lack of precision in the immunotherapy strategy tailored for patients exhibiting diverse clinical characteristics. This study aims to employ a rigorous network meta-analysis (NMA) approach to systematically evaluate the effectiveness of immune-combination therapies among patients with advanced hepatocellular carcinoma, taking into account their varying clinico-characteristics. METHODS: Studies were retrieved from PubMed, Embase, Cochrane Library, and Web of Science databases. The included first-line phase III studies were categorized into three types: immunotherapy combined with anti-angiogenetic agents, immunotherapy combined with tyrosine kinase inhibitors, and dual immunotherapy, with sorafenib serving as the control group. The primary endpoint used to assess efficacy was overall survival (OS), facilitating a comparative analysis among the three treatment modalities. Furthermore, subgroup analyses were conducted to evaluate the varying effectiveness for patients with diverse clinico-characteristics. Secondary outcome measures included progression-free survival, objective response rate, and toxicity assessment. RESULTS: A total of 6 studies were included in the NMA, encompassing a cohort of 3840 patients. The results revealed that immunotherapy combined with anti-angiogenetic agents exhibited a significantly enhanced therapeutic effect in terms of improving OS compared to sorafenib (HR = 0.61, 95% CrI, 0.42-0.90). Furthermore, based on various clinicopathological features, this combination therapy demonstrated superior OS responses in specific patient subgroups: BCLC C (HR = 0.63, 95% CrI, 0.42-0.93), ECOG 1 (HR = 0.57, 95% CrI, 0.36-0.91), with extrahepatic spread (EHS) (HR = 0.59, 95% CrI, 0.37-0.92), alpha fetoprotein (AFP)<400ng/ml (HR = 0.56, 95% CrI, 0.33-0.94) and viral hepatitis positivity (HR = 0.56, 95% CrI, 0.39-0.77) (especially HBV (HR = 0.58, 95% CrI, 0.40-0.85)). Importantly, the advantage of this combination therapy was even more pronounced in patients with viral hepatitis positivity. Also, the adverse events associated with immunotherapy combined with antiangiogenic drugs were moderate. CONCLUSIONS: Immunotherapy combined with anti-angiogenetic agents could represent the most effective first-line intervention for achieving improved OS, particularly in patients with viral hepatitis positivity.