Understanding gut dysbiosis for hepatocellular carcinoma diagnosis and treatment

Gut microbiota in hepatocellular carcinoma immunotherapy: immune microenvironment remodeling and gut microbiota modification

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality, with limited treatment options at advanced stages. The gut microbiota, a diverse community of microorganisms residing in the gastrointestinal tract, plays a pivotal role in regulating immune responses through the gut-liver axis. Emerging evidence underscores its impact on HCC progression and the efficacy of immunotherapy. This review explores the intricate interactions between gut microbiota and the immune system in HCC, with a focus on key immune cells and pathways involved in tumor immunity. Additionally, it highlights strategies for modulating the gut microbiota - such as fecal microbiota transplantation, dietary interventions, and probiotics - as potential approaches to enhancing immunotherapy outcomes. A deeper understanding of these mechanisms could pave the way for novel therapeutic strategies aimed at improving patient prognosis.

Porphyran from discolored nori prevents metabolic syndrome through microbiota-bile acid-ceramide pathway

Nori is a component of the traditional Japanese diet. The Japanese have a low prevalence of obesity and cardiovascular disease worldwide, and components of nori may have disease-preventive effects. Here, we focused on porphyran, which is abundant in nori that is discarded due to discoloration, and investigated the effects of nori-derived porphyran on gut microbiota, bile acid composition, and ceramide synthesis. Administration of porphyran to mice prevented obesity, diabetes, metabolic dysfunction-associated steatohepatitis (MASH), and hepatocellular carcinoma (HCC). This improvement correlates with a decrease in secondary bile acids, a decrease in intestinal farnesoid X receptor (FXR) signaling, and a marked decrease in blood ceramide. Porphyran, abundant in discolored nori, should be the subject of future translational research to prevent diseases with significant unmet medical needs and improve global environmental sustainability.

Nanomaterials in the diagnosis and treatment of gastrointestinal tumors: New clinical choices and treatment strategies

Nanomaterials have emerged as a promising modality in the diagnosis and treatment of gastrointestinal (GI) tumors, offering significant advancements over conventional methods. In diagnostic applications, nanomaterials facilitate enhanced imaging techniques, including magnetic resonance imaging (MRI), computed tomography (CT), and fluorescence imaging, which provide improved resolution and more accurate detection of early-stage cancers. Nanoparticles (NPs), such as liposomes, dendrimers, and quantum dots, are increasingly employed for the targeted imaging of specific biomarkers associated with GI malignancies, thereby enhancing diagnostic sensitivity and specificity. Liposomes are primarily used for drug delivery due to their ability to encapsulate hydrophobic drugs, dendrimers are useful for both drug delivery and gene therapy due to their highly branched structure, and quantum dots are primarily used in imaging and diagnostics because of their fluorescent properties. We also discuss their respective advantages and limitations. In therapeutic contexts, nanomaterials play a pivotal role in the development of targeted drug delivery systems. These systems address the limitations of traditional chemotherapy by improving drug bioavailability, reducing systemic toxicity, and promoting selective accumulation at tumor sites via both passive and active targeting mechanisms. Nanomedicines, including NPs and nanocarriers, enable the precise delivery of chemotherapeutic agents, nucleic acid -based therapies, and immunomodulators directly to cancer cells, thereby optimizing therapeutic efficacy. Furthermore, nanotechnology offers the potential to modulate the tumor microenvironment (TME), a critical factor in overcoming challenges related to tumor resistance and metastasis. Despite these promising advancements, several challenges persist, including concerns regarding long-term toxicity, stability, and regulatory approval. Nonetheless, the integration of nanomaterials into clinical practice holds substantial potential for revolutionizing the management of GI cancers, paving the way for more precise, personalized, and effective therapeutic strategies.

Immunosenescence and immunotherapy in elderly patients with hepatocellular carcinoma

Liver cancer, more specifically hepatocellular carcinoma (HCC), is a global health issue and one of the dominant causes of cancer death around the world. In the past few decades, remarkable advances have been achieved in the systemic therapy of HCC. Immune checkpoint inhibitors (ICIs) have become a therapy mainstay for advanced HCC and have shown promise in the neoadjuvant therapy before resection. Despite these significant advancements, the compositions and functions of the immune system occur various alterations with age, called "immunosenescence", which may affect the antitumor effects and safety of ICIs, thus raising concerns that immunosenescence may impair elderly patients' response to ICIs. Therefore, it is important to learn more about the immunosenescence characteristics of elderly patients. However, the real-world elderly HCC patients may be not accurately represented by the elderly patients included in the clinical trials, affecting the generalizability of the efficacy and safety profiles from the clinical trials to the real-world elderly patients. This review summarizes the characteristics of immunosenescence and its influence on HCC progression and immunotherapy efficacy as well as provides the latest progress in ICIs available for HCC and discusses their treatment efficacy and safety on elderly patients. In the future, more studies are needed to clarify the mechanisms of immunosenescence in HCC, and to find sensitive screening tools or biomarkers to identify the patients who may benefit from ICIs.

Radiosensitization Strategies for Hepatocellular Carcinoma: Mechanisms, Therapeutic Advances, and Clinical Perspectives

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide, with treatment efficacy limited by late-stage diagnosis, frequent recurrence, and therapeutic resistance. Radiotherapy is a key local treatment for HCC; however, its efficacy is frequently limited by intrinsic tumor radioresistance. This review discusses strategies to improve the therapeutic response of HCC to radiotherapy. Targeting DNA repair mechanisms can block tumor cells from recovering after radiation-induced damage, whereas modulating cell cycle arrest and programmed cell death pathways (e.g., apoptosis, autophagy) diminishes their survival capacity. Furthermore, remodeling the tumor microenvironment-through hypoxia alleviation, metabolic reprogramming, oxidative stress regulation, and immune activation-may potentiate radiotherapy efficacy. Technological advances, such as stereotactic body radiotherapy and nanomaterial-based approaches, have also improved the precision and effectiveness of radiotherapy. Clinically, combining radiotherapy with systemic therapies (e.g., immune checkpoint inhibitors and antiangiogenic agents) has demonstrated preliminary promise in enhancing treatment outcomes. However, translating preclinical findings into clinical practice remains challenging due to tumor heterogeneity, normal tissue toxicity, and the lack of predictive biomarkers for treatment selection. Future research should focus on integrating molecular profiling with multimodal therapies to enable personalized radiosensitization and bridge the gap between mechanistic insights and clinical outcomes.

The gastrointestinal mycobiome in inflammation and cancer: unraveling fungal dysbiosis, pathogenesis, and therapeutic potential

The gastrointestinal mycobiome, comprising diverse fungal species, plays a significant role in gastrointestinal carcinogenesis and inflammatory bowel disease (IBD) pathogenesis. Recent studies have demonstrated that dysbiosis of the gut mycobiome, characterized by an overrepresentation of pathogenic fungi such as Candida albicans and Aspergillus, correlates with increased inflammation and cancer risk. For instance, C. albicans has been shown to induce colonic inflammation through the activation of pattern recognition receptors and the release of pro-inflammatory cytokines, exacerbating IBD symptoms and potentially facilitating tumorigenesis. Additionally, metagenomic analyses have revealed distinct fungal signatures in colorectal cancer tissues compared to adjacent healthy tissues, highlighting the potential of fungi as biomarkers for disease progression. Mechanistically, gut fungi contribute to disease through biofilm formation, mycotoxin secretion (e.g., aflatoxins, candidalysin), pro-inflammatory cytokine induction (e.g., IL-1β, IL-17), and disruption of epithelial barriers-creating a tumor-promoting and inflammation-prone environment. Furthermore, the interplay between fungi and the bacterial microbiome can amplify inflammatory responses, contributing to chronic inflammation and cancer development. Fungal interactions with bacterial communities also play a synergistic role in shaping mucosal immune responses and enhancing disease severity in both cancer and IBD contexts. As research continues to elucidate these complex fungal-host and fungal-bacterial interactions, targeting the gut mycobiome may offer novel therapeutic avenues for managing IBD and gastrointestinal cancers, emphasizing the need for integrated, mechanistically informed approaches to microbiome research.

Malignant tumors in vagal-innervated organs: Exploring its homeostatic role

Cancer remains a significant global health challenge, with its progression shaped by complex and multifactorial mechanisms. Recent research suggests that the vagus nerve could play a critical role in mediating communication between the tumor microenvironment and the central nervous system (CNS). This review highlights the diversity of vagal afferent receptors, which could position the vagus nerve as a unique pathway for transmitting immune, metabolic, mechanical, and chemical signals from tumors to the CNS. Such signaling could influence systemic disease progression and tumor-related responses. Additionally, the vagus nerve's interactions with the microbiome and the renin-angiotensin system (RAS)-both implicated in cancer biology-further underscore its potential central role in modulating tumor-related processes. Contradictions in the literature, particularly concerning vagal fibers, illustrate the complexity of its involvement in tumor progression, with both tumor-promoting and tumor-suppressive effects reported depending on cancer type and context. These contradictions often overlook certain experimental biases, such as the failure to distinguish between vagal afferent and efferent fibers during vagotomies or the localized parasympathetic effects that cannot always be extrapolated to the systemic level. By focusing on the homeostatic role of the vagus nerve, understanding these mechanisms could open the door to new perspectives in cancer research related to the vagus nerve and lead to potential therapeutic innovations.

The Role of the Gut-Biliary-Liver Axis in Primary Hepatobiliary Liver Cancers: From Molecular Insights to Clinical Applications

Background: Hepatobiliary liver cancers (HBLCs) represent the sixth most common neoplasm in the world. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) constitute the main HBLC types, with alarming epidemiological projections. Methods: In recent decades, alterations in gut microbiota, with mutual implications on the gut-liver axis and gut-biliary axis permeability status, have been massively investigated and proposed as HBLC pathogenetic deus ex machina. Results: In the HCC setting, elevated intestinal levels of Escherichia coli and other Gram-negative bacteria have been demonstrated, resulting in a close association with increased lipopolysaccharide (LPS) serum levels and, consequently, chronic systemic inflammation. In contrast, the intestinal microbiota of HCC individuals feature reduced levels of Lactobacillus spp., Bifidobacterium spp., and Enterococcus spp. In the CC setting, evidence has revealed an increased expression of Lactobacillus spp., with enhanced levels of Actynomices spp. and Alloscardovia spp. Besides impaired strains/species representation, gut-derived metabolites, including bile acids (BAs), short-chain fatty acids (SCFAs), and oxidative-stress-derived products, configure a network severely impacting the progression of HBLC. Conclusions: In the era of Precision Medicine, the clarification of microbiota composition and functioning in HCC and CC settings can contribute to the identification of individual signatures, potentially providing novel diagnostic markers, therapeutic approaches, and prognostic/predictive tools.

Liver fibrosis as a barometer of systemic health by gauging the risk of extrahepatic disease

This review article proposes the theory that liver fibrosis, the abnormal accumulation of excessive extracellular matrix, is not just an indicator of liver disease but also a negative reflection of overall systemic health. Liver fibrosis poses a heavy financial burden on healthcare systems worldwide and can develop due to chronic liver disease from various causes, often due to sustained inflammation. Liver fibrosis may not generate symptoms and become apparent only when it reaches the stage of cirrhosis and is associated with clinically significant portal hypertension and leads to decompensation events or promotes the development of hepatocellular carcinoma. While chronic viral hepatitis and excessive alcohol consumption were once the primary causes of chronic liver disease featuring fibrosis, this role is now increasingly taken over by metabolic dysfunction-associated steatotic liver disease (MASLD). In MASLD, endothelial dysfunction is an essential component in pathogenesis, promoting the development of liver fibrosis, but it is also present in endothelial cells of other organs such as the heart, lungs, and kidneys. Accordingly, liver fibrosis is a significant predictor of liver-related outcomes, as well as all-cause mortality, cardiovascular risk, and extrahepatic cancer. Physicians should be aware that individuals seeking medical attention for reasons unrelated to liver health may also have advanced fibrosis. Early identification of these at-risk individuals can lead to a more comprehensive assessment and the use of various treatment options, both approved and investigational, to slow or reverse the progression of liver fibrosis.

Intratumoral microbiota: an emerging force in diagnosing and treating hepatocellular carcinoma

Hepatocellular carcinoma (HCC) ranks among the most prevalent types of cancer in the world and its incidence and mortality are increasing year by year, frequently diagnosed at an advanced stage. Traditional treatments such as surgery, chemotherapy, and radiotherapy have limited efficacy, so new diagnostic and treatment strategies are urgently needed. Recent research has discovered that intratumoral microbiota significantly influences the development, progression, and metastasis of HCC by modulating inflammation, immune responses, and cellular signaling pathways. Intratumoral microbiota contributes to the pathologic process of HCC by influencing the tumor microenvironment and altering the function of immune system. This article reviews the mechanism of intratumoral microbiota in HCC and anticipates the future possibilities of intratumoral microbiota-based therapeutic strategies for HCC management. This emerging field provides fresh insights into early diagnosis and personalized approaches for HCC while holding substantial clinical application potential to improve patient outcomes and tailor interventions to individual tumor profiles.