Perspective on the Role of Gut Microbiome in the Treatment of Hepatocellular Carcinoma with Immune Checkpoint Inhibitors

The gut microbiota: an emerging modulator of drug resistance in hepatocellular carcinoma

Liver cancer is usually diagnosed at an advanced stage and is the third most common cause of cancer-related death worldwide. In addition to the lack of effective treatment options, resistance to therapeutic drugs is a major clinical challenge. The gut microbiota has recently been recognized as one of the key factors regulating host health. The microbiota and its metabolites can directly or indirectly regulate gene expression in the liver, leading to gut-liver axis dysregulation, which is closely related to liver cancer occurrence and the treatment response. Gut microbiota disturbance may participate in tumor progression and drug resistance through metabolite production, gene transfer, immune regulation, and other mechanisms. However, systematic reviews on the role of the gut microbiota in drug resistance in liver cancer are lacking. Herein, we review the relationships between the gut microbiota and the occurrence and drug resistance of hepatocellular carcinoma, summarize the emerging mechanisms underlying gut microbiota-mediated drug resistance, and propose new personalized treatment options to overcome this resistance.

Exploring the Potential of Ellagic Acid in Gastrointestinal Cancer Prevention: Recent Advances and Future Directions

Gastrointestinal (GI) cancers are a significant global health concern with diverse etiologies and limited treatment options. Ellagic acid (EA), a natural polyphenolic compound, exhibits promising anticancer properties against various GI malignancies. In this article, we have reviewed recent research on the anticancer potential of EA across esophageal, gastric, colorectal, pancreatic, and liver cancers. In esophageal cancer, EA inhibits the formation of O6-methylguanine (O6-meGua) adducts induced by carcinogens like N-nitrosomethylbenzylamine (NMBA), thereby suppressing tumor growth. Additionally, EA inhibits STAT3 signaling and stabilizes tumor suppressor proteins, showing potential as an anti-esophageal cancer agent. In gastric cancer, EA regulates multiple pathways involved in cell proliferation, invasion, and apoptosis, including the p53 and PI3K-Akt signaling pathways. It also demonstrates anti-inflammatory and antioxidant effects, making it a promising therapeutic candidate against gastric cancer. In colorectal cancer (CRC), EA inhibits cell proliferation, induces apoptosis, and modulates the Wnt/β-catenin and PI3K/Akt pathways, suggesting its efficacy in preventing CRC progression. Furthermore, EA has shown promise in pancreatic cancer by inhibiting nuclear factor-kappa B, inducing apoptosis, and suppressing epithelial-mesenchymal transition. In liver cancer, EA exhibits radio-sensitizing effects, inhibits inflammatory pathways, and modulates the tumor microenvironment, offering potential therapeutic benefits against hepatocellular carcinoma. Studies on EA potential in combination therapies and the development of targeted delivery systems are required for enhanced efficacy against gastrointestinal cancers.

Therapeutic success in primary biliary cholangitis and gut microbiota: a safe highway?

Primary biliary cholangitis (PBC) is a chronic, cholestatic, autoimmune disease, characterized by destruction of bile ducts. PBC predominantly affects women between 40 and 60 years of age. The presence of antimitochondrial antibodies (AMA) is a serological feature of PBC. These highly specific antibodies are found in about 95% of patients with the disease. The family of enzymes located in the inner membrane of the mitochondria, called the 2-oxo-acid dehydrogenase complex represents the target of the AMA. Ursodeoxycholic acid (UDCA) is a synthetic bile acid capable of protecting cholangiocytes from cholestatic damage caused by the accumulation of bile acids with a mechanism of action not yet well clarified. UDCA represents the gold standard therapy for PBC patients with recommended dose of 13-15 mg/kg/day. However, not every patient responds to therapy. On the other hand, the gut microbiota plays a key role in the onset of PBC through still unclear biochemical pathways. Less is known about its role as a potential biomarker after drug treatment. Actually, few studies analyzed the changes in gut microbiota composition before and after UDCA treatment. For this reason, this review represents an examination of the studies carried out on changes in gut microbiota composition in patients affected by PBC before and after treatment.

Use of Non-Invasive Biomarkers and Clinical Scores to Predict the Complications of Liver Cirrhosis: A Bicentric Experience

Background and objectives: Liver cirrhosis is a chronic, progressive condition characterized by fibrosis and architectural distortion of the liver, leading to impaired liver function and severe complications. Accurately predicting these complications is crucial to the improvement of patient outcomes. Therefore, this study aimed to evaluate the accuracy of various non-invasive biomarkers and clinical scores in assessing the risk of complications among cirrhotic patients. Materials and methods: We conducted an observational retrospective study involving 236 cirrhotic patients from two tertiary care hospitals in Italy and Romania, in a timespan ranging from January 2021 to March 2024. Data on clinical characteristics, liver function tests, hematological indices, various non-invasive biomarkers, and clinical scores were collected and analyzed. Receiver operating characteristic analysis was performed to assess the accuracy of these biomarkers and clinical scores in predicting complications, including the presence of varices and hepato-renal syndrome. Results: The Child-Pugh score showed the highest accuracy for cirrhosis-related complications, with an area under curve (AUC) = 0.667. The red cell distribution width coefficient of variation followed closely with an AUC = 0.646. While the Child-Pugh score had a high specificity (85.42%), its sensitivity was low (37.97%). In patients with varices, non-invasive scores such as platelet distribution width (PDW) and the RDW-to-platelet ratio (RPR) showed modest predictive ability, with an AUC = 0.594. For hepato-renal syndrome, the Model for End-Stage Liver Disease (MELD) score showed the highest diagnostic accuracy with an AUC = 0.758. Conclusions: The most reliable biomarkers for detecting complications, varices, and hepato-renal syndrome, are, respectively, the Child-Pugh Score, PDW along with RPR, and the MELD score. However, while these scores remain valuable, the moderate diagnostic accuracy of other indices suggests the need for a more integrated approach to risk stratification. Future research should focus on validating these tools across different populations and incorporating emerging biomarkers to enhance predictive accuracy and inform more effective clinical decision-making.

Single-cell and spatial transcriptomics reveal apelin/APJ pathway's role in microvessel formation and tumour progression in hepatocellular carcinoma

The apelin receptor (APJ) is a key player in tumour angiogenesis, but its role in hepatocellular carcinoma (HCC) remains unclear. This study aims to elucidate the function of the apelin/APJ pathway in HCC using a multi-omics approach and identify potential therapeutic biomarkers. Differentially expressed genes related to the apelin/APJ axis were identified from bulk transcriptomics to reveal HCC-associated disparities. Single-cell and spatial transcriptomics were used to localize and analyse the function of these genes. Machine learning models were constructed to predict outcomes based on apelin/APJ expression, and experimental validation was conducted to explore the pathway's impact on HCC angiogenesis. Single cell analysis revealed an overexpression of APJ/Aplin in the endothelium. The stemness of endothelial cell (EC) with high apelin/APJ was enhanced, as well as the expression of TGFb, oxidative stresses and PI3K/AKT pathway genes. Spatial transcriptomics confirmed that EC populations with high APJ scores were enriched within the tumour. Machine learning models showed high prognostic accuracy. High APJ expression was linked to worse outcomes (p = 0.001), and AUC values were high (1 year, 3 year, 5 year) (0.95, 0.97, 0.98). Immune suppression and non-responsiveness of immune therapy were also seen in high-risk groups. The experimental validation showed that silencing apelin reduced angiogenesis (p  < 0.05), endothelial proliferation, decreased expression of ANG2, KLF2, VEGFA and lower ERK1/2 phosphorylation. Apelin may serve as a potential therapeutic target in HCC, given its role in promoting tumour angiogenesis and poor patient outcomes.

Epidemiology, pathophysiology and clinical aspects of Hepatocellular Carcinoma in MAFLD patients

Hepatocellular carcinoma (HCC) is undergoing a transformative shift, with metabolic-associated fatty liver disease (MAFLD) emerging as a dominant etiology. Diagnostic criteria for MAFLD involve hepatic steatosis and metabolic dysregulation. Globally, MAFLD prevalence stands at 38.77%, significantly linked to the escalating rates of obesity. Epidemiological data indicate a dynamic shift in the major etiologies of hepatocellular carcinoma (HCC), transitioning from viral to metabolic liver diseases. Besides the degree of liver fibrosis, several modifiable lifestyle risk factors, such as type 2 diabetes, obesity, alcohol use, smoking, and HBV, HCV infection contribute to the pathogenesis of HCC. Moreover  gut microbiota and genetic variants may contribute to HCC development.The pathophysiological link between MAFLD and HCC involves metabolic dysregulation, impairing glucose and lipid metabolism, inflammation and oxidative stress. Silent presentation poses challenges in early MAFLD-HCC diagnosis. Imaging, biopsy, and AI-assisted techniques aid diagnosis, while HCC surveillance in non-cirrhotic MAFLD patients remains debated.ITA.LI.CA. group proposes a survival-based algorithm for treatment based on Barcelona clinic liver cancer (BCLC) algorithm. Liver resection, transplantation, ablation, and locoregional therapies are applied based on the disease stage. Systemic treatments is promising, with initial immunotherapy results indicating a less favorable response in MAFLD-related HCC.Adopting lifestyle interventions and chemopreventive measures with medications, including aspirin, metformin, and statins, constitute promising approaches for the primary prevention of HCC.Prognosis is influenced by multiple factors, with MAFLD-HCC associated with prolonged survival. Emerging diagnostic biomarkers and epigenomic markers, show promising results for early HCC detection in the MAFLD population.

Clinical model to predict the risk of nonalcoholic fatty liver disease: A secondary analysis of data from a cross-sectional study

This study aimed to develop and validate a clinical model for predicting the risk of nonalcoholic fatty liver disease (NAFLD) by using data from a cross-sectional study. This investigation utilized data from the Dryad database and employed multivariable logistic regression analysis, restricted cubic spline, and nomogram analysis to achieve comprehensive insights. The discrimination and calibration of the nomogram were evaluated using the receiver operating characteristic curve and calibration plot. A total of 1072 patients were included in the study, including 456 with non-NAFLD and 616 with NAFLD. Significant differences were observed in terms of sex, body mass index (BMI), tobacco, hypertension, diabetes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), ALT/AST ratio, uric acid (UA), fasting blood glucose (FBG), triglyceride (TG), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, systolic blood pressure, and diastolic blood pressure (P < .05 for all comparisons). Multivariable logistic regression analysis indicated that sex, BMI, diabetes, ALT/AST ratio, UA, FBG, and TG were associated with an increased risk of NAFLD. Restricted cubic spline indicated a nonlinear relationship between the risk of NAFLD and variables including ALT/AST ratio, FPG, TG, and UA (P for nonlinearity < .01). The variables in the nomogram included BMI, diabetes, ALT/AST ratio, UA, FBG, and TG. The value of area under the curve was 0.790, indicating that the nomogram prediction model exhibited significant discriminatory accuracy. A reliable clinical model for predicting the risk of NAFLD was developed using readily available clinical data. The model can assist clinicians in identifying individuals with an increased risk of NAFLD, enabling early interventions for preventing and managing this prevalent liver disease.

Gut Microbiota, Deranged Immunity, and Hepatocellular Carcinoma

BACKGROUND

Liver cancer, particularly hepatocellular carcinoma (HCC), is a significant gastrointestinal disease with a mortality rate as high as nearly 80% within five years. The disease's pathophysiology involves deranged immune responses and bile acid metabolism, with the gut microbiota (GM) playing a crucial role. Recent research highlights the potential of GM in influencing HCC treatment outcomes, especially regarding immune checkpoint inhibitors (ICIs). However, few patients currently benefit from ICIs due to a lack of effective response biomarkers.

AIMS AND METHODS

This review aimed to explore the literature on HCC treatment issues, focusing on immune response, bile acid metabolism, and GM dysbiosis. This review included studies from PubMed, Medline, and major gastroenterology and hepatology meetings, using keywords like gut microbiota, immune system, liver cancer, and checkpoint inhibitors.

RESULTS

GM dysbiosis significantly impacts immune response and bile acid metabolism, making it a promising biomarker for ICI response. Modulating GM can enhance ICI treatment efficacy, although more research is needed to confirm its direct therapeutic benefits for HCC.

CONCLUSIONS

GM dysbiosis is integral to liver cancer pathogenesis and treatment response. Its modulation offers promising therapeutic avenues for improving HCC prognosis and response to immunotherapy.

Impact of diet and gut microbiota changes in the development of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer that occurs with a frequency of 85% in patients with liver cirrhosis. It is the sixth most common type of cancer globally. Asia is the continent with the highest incidence (72%), followed by Europe (8%) and Africa (5%). Men are four times more likely than women to develop this cancer, especially in the 70-80 age group. Risk factors include alcoholic liver disease, tobacco use, genetic predisposition, dysmetabolic comorbidities such as type 2 diabetes mellitus and obesity, hepatitis B virus and hepatitis C virus infections, and non-alcoholic fatty liver disease. Unhealthy dietary regimens and gut dysbiosis are additional risk factors that have been recently investigated. These two factors are closely related because the gut microbiota performs several biological functions, including nutrient metabolism, a process that promotes gut homeostasis, known as eubiosis. With regard to the correlation between diet, gut microbiota, and HCC development, there are several mechanisms that have not yet been fully elucidated. This narrative review aims to evaluate the impact of diet and gut microbiota changes in the development of HCC. Our analysis, performed on several clinical and pre-clinical studies, showed that a high-fat diet promotes gut dysbiosis and hepatic fat accumulation, leading to the progression from simple steatosis to HCC, while the Mediterranean diet, rich in fiber and monounsaturated fatty acids, had a protective role. For this reason, international employment of this dietary regimen for therapeutic purposes should be encouraged.

Liver cancer wars: plant-derived polyphenols strike back

Liver cancer currently represents the leading cause of cancer-related death worldwide. The majority of liver cancer arises in the context of chronic inflammation and cirrhosis. Surgery, radiation therapy, and chemotherapy have been the guideline-recommended treatment options for decades. Despite enormous advances in the field of liver cancer therapy, an effective cure is yet to be found. Plant-derived polyphenols constitute a large family of phytochemicals, with pleiotropic effects and little toxicity. They can drive cellular events and modify multiple signaling pathways which involves initiation, progression and metastasis of liver cancer and play an important role in contributing to anti-liver cancer drug development. The potential of plant-derived polyphenols for treating liver cancer has gained attention from research clinicians and pharmaceutical scientists worldwide in the last decades. This review overviews hepatic carcinogenesis and briefly discusses anti-liver cancer mechanisms associated with plant-derived polyphenols, specifically involving cell proliferation, apoptosis, autophagy, angiogenesis, oxidative stress, inflammation, and metastasis. We focus on plant-derived polyphenols with experiment-based chemopreventive and chemotherapeutic properties against liver cancer and generalize their basic molecular mechanisms of action. We also discuss potential opportunities and challenges in translating plant-derived polyphenols from preclinical success into clinical applications.

The Role of Cytokines in the Pathogenesis and Treatment of Alcoholic Liver Disease

Alcoholic liver disease (ALD) is a major cause of chronic liver disease. This term covers a broad spectrum of liver lesions, from simple steatosis to alcoholic hepatitis and cirrhosis. The pathogenesis of ALD is multifactorial and not fully elucidated due to complex mechanisms related to direct ethanol toxicity with subsequent hepatic and systemic inflammation. The accumulation of pro-inflammatory cytokines and the reduction of anti-inflammatory cytokines promote the development and progression of ALD. To date, there are no targeted therapies to counter the progression of chronic alcohol-related liver disease and prevent acute liver failure. Corticosteroids reduce mortality by acting on the hepatic-systemic inflammation. On the other hand, several studies analyzed the effect of inhibiting pro-inflammatory cytokines and stimulating anti-inflammatory cytokines as potential therapeutic targets in ALD. This narrative review aims to clarify the role of the main cytokines involved in the pathogenesis and treatment of ALD.