The Tumor Microenvironment in Cholangiocarcinoma Progression

Heterogeneity and plasticity of cholangiocytes in liver injury: a journey from pathophysiology to therapeutic utility

Cholangiocytes are highly specialised cells participating in the pathobiology of various liver diseases and recognised to play a crucial role in response to liver injury. Cholangiocytes exhibit dramatic heterogeneity and plasticity, with distinct subtypes performing disparate functions during liver injury and regeneration. Acting as the liver progenitor cells, cholangiocytes can also convert to hepatocytes in the context of impaired hepatocyte proliferation. Harnessing the intrinsic regenerative ability of cholangiocytes is of great importance to alleviate liver injury and promote cholangiocyte-driven liver regeneration. Clinically, cholangiocytes and cholangiocyte organoids are expected to serve as favourable sources for cell therapy in cholangiopathies, which are known as a group of complex diseases involving the biliary system while lacking effective therapeutic options. A comprehensive understanding of the biological characteristics of cholangiocytes provides insights into developing cholangiocyte cell therapy for cholangiopathies. In this review, we discuss the critical role of cholangiocytes in liver injury and regeneration, reveal the underlying mechanism of cholangiocyte plasticity, and explore the prospects and challenges of using cholangiocytes as a source for cell therapy.

Causal role of immune cells in primary liver cancer: a mendelian randomization study

BACKGROUND

Primary liver cancer is one of the most common fatal malignancies worldwide. Observational studies have shown that immune cells are closely linked to primary liver cancer, however, due to issues like reverse causality and confounding variables, the causal direction and extent of this association remain unclear. Thus, this study aimed to explore the potential causal association between immune cells and primary liver cancer, encompassing hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC).

METHODS

A two-sample mendelian randomization (MR) analysis was performed using summary statistics from genome-wide association studies (GWAS) of the 731 immune traits and primary liver cancer. The primary liver cancer dataset consisted of a total of 456,348 subjects, with 123 cases of HCC and 456,225 controls, as well as 104 cases of ICC and 456,244 controls, all of European ancestry. The primary method for assessing causality was inverse variance weighting (IVW), with sensitivity analysis utilized for testing heterogeneity and pleiotropy.

RESULTS

Two immunophenotypes were significantly associated with HCC risk: CD3 on CD45RA + CD4+ (OR [95% CI]: 1.334 [1.077 to 1.651], p = 0.008), CD80 on monocyte (OR [95% CI]: 0.578 [0.397 to 0.844], p = 0.004). Additionally, six immunophenotypes were identified to be significantly associated with the risk of ICC: SSC-A on NK (OR [95% CI]: 1.685 [1.166 to 2.436], p = 0.006); CD3 on CD28- CD8br: (OR [95% CI]: 1.826 [1.206 to 2.766], p = 0.004); CD45RA on naive CD4+: (OR [95% CI]: 1.391 [1.119 to 1.729], p = 0.003); Resting Treg %CD4: (OR [95% CI]: 1.290 [1.069 to 1.558], p = 0.008); HLA DR on HSC: (OR [95% CI]: 0.539 [0.343 to 0.846], p = 0.007); Plasmacytoid DC %DC: (OR [95% CI]: 0.610 [0.462 to 0.806], p < 0.001). And sensitivity analyses confirmed the robustness of the main findings.

CONCLUSIONS

MR analysis has revealed the causal relationship between immune cells and primary liver cancer through genetic methods. These findings could assist in clinical decision-making and provide new directions for the treatment and research of primary liver cancer.

Tumor diagnosis recharacterization enabled by comprehensive genomic profiling to guide precision medicine strategy

Comprehensive genomic profiling (CGP) via next-generation sequencing is standard clinical practice for advanced and metastatic cancers in the U.S. and can help identify clinically actionable alterations in patients who may benefit from targeted therapies. CGP can also complement clinicopathological findings and in certain cases, may lead to diagnostic recharacterization resulting in more precise therapeutic strategies. Here, we highlight examples where molecular findings resulted in tumor re-evaluation and subsequent recharacterization. Twenty-eight cases where CGP results were inconsistent with initial pathological diagnosis and clinical presentation were selected for secondary clinicopathological review to explore alternative diagnostic explanations more consistent with the genomic results. Genomic profiling identified clinically actionable and prognostic variants leading to more accurate therapeutic recommendations based on the updated diagnoses highlighting the value of CGP beyond biomarker detection for therapy selection and supporting its complementary use in diagnostic confirmation to unveil opportunities for precision medicine strategies.

Prognosis of cholangiocarcinoma patients based on multiple patterns of programmed cell death, integrated analysis of the immune microenvironment and drug sensitivity

Background

Cholangiocarcinoma (CHOL) is a highly malignant bile duct cancer with a poor prognosis and rising incidence. Programmed cell death (PCD) plays a crucial role in cancer biology, influencing tumor immunity and treatment response. This study analyzes the impact of multiple PCD patterns on CHOL prognosis, tumor microenvironment (TME) and drug sensitivity.

Methods

RNA sequencing data from TCGA-CHOL and GSE107943 were analyzed to identify PCD-related genes. A PCD-associated Risk Score was constructed using Cox and Lasso regression analyses. The score's prognostic value was assessed through survival analysis, ROC curves, and functional annotation.

Results

We identified 111 differentially expressed PCD-related genes, including NCK2, BNIP3 and BIK, that constituted PCD-associated Risk Score and correlated with prognosis of CHOL. Functional analyses indicated enrichment in immune-related processes. High-risk patients showed increased immune cell infiltration and higher immune checkpoint expression, suggesting a benefit from immunotherapy. They also demonstrated greater sensitivity to several chemotherapeutic and targeted agents.

Conclusion

PCD-associated Risk Score is a robust prognostic tool for CHOL, influencing TME modulation and therapeutic response, and may guide personalized treatment strategies.

The function of necroptosis in liver cancer

Liver cancer is one of the most lethal cancers, and apoptosis resistance is a major obstacle contributing to chemotherapy failure in liver cancer treatment. Inducing cancer cell death by bypassing the apoptotic pathway is considered a promising approach to overcome this problem. Necroptosis is a non-caspase-dependent regulated mode of cell death mainly mediated by receptor-interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like (MLKL) protein, and the utilization of necroptosis for treating hepatocellular carcinoma (HCC) also offers a new hope for addressing liver cancer in the clinic. In this paper, the role of necroptosis in HCC as well as the effect on differentiation of liver cancer are reviewed. We also comparatively analyze the relationship among necroptosis, apoptosis, and necrosis, as well as summarize the characteristics and functions of key proteins involved in this pathway. The bidirectional regulation of necroptosis and the mitochondrial machinery within this pathway deserve attention.

Role of genomics in liver transplantation for cholangiocarcinoma

PURPOSE OF REVIEW

The purpose of this review is to summarize the current knowledge of cholangiocarcinoma molecular biology and to suggest a framework for implementation of next-generation sequencing in all stages of liver transplantation. This is timely as recent guidelines recommend increased use of these technologies with promising results.

RECENT FINDINGS

The main themes covered here address germline and somatic genetic alterations recently discovered in cholangiocarcinoma, particularly those associated with prognosis and treatment responses, and nascent efforts to translate these into contemporary practice in the peri-liver transplantation period.

SUMMARY

Early efforts to translate molecular profiling to cholangiocarcinoma care demonstrate a growing number of potentially actionable alterations. Still lacking is a consensus on what biomarkers and technologies to adopt, at what scale and cost, and how to integrate them most effectively into care with the ambition of increasing the number of patients eligible for liver transplantation and improving their long-term outcomes.

Portal Fibrosis and the Ductular Reaction: Pathophysiological Role in the Progression of Liver Disease and Translational Opportunities

A consistent feature of chronic liver diseases and the hallmark of pathologic repair is the so-called "ductular reaction." This is a histologic abnormality characterized by an expansion of dysmorphic cholangiocytes inside and around portal spaces infiltrated by inflammatory, mesenchymal, and vascular cells. The ductular reaction is a highly regulated response based on the reactivation of morphogenetic signaling mechanisms and a complex crosstalk among a multitude of cell types. The nature and mechanism of these exchanges determine the difference between healthy regenerative liver repair and pathologic repair. An orchestrated signaling among cell types directs mesenchymal cells to deposit a specific extracellular matrix with distinct physical and biochemical properties defined as portal fibrosis. Progression of fibrosis leads to vast architectural and vascular changes known as "liver cirrhosis." The signals regulating the ecology of this microenvironment are just beginning to be addressed. Contrary to the tumor microenvironment, immune modulation inside this "benign" microenvironment is scarcely known. One of the reasons for this is that both the ductular reaction and portal fibrosis have been primarily considered a manifestation of cholestatic liver disease, whereas this phenomenon is also present, albeit with distinctive features, in all chronic human liver diseases. Novel human-derived cellular models and progress in "omics" technologies are increasing our knowledge at a fast pace. Most importantly, this knowledge is on the edge of generating new diagnostic and therapeutic advances. Here, we will critically review the latest advances, in terms of mechanisms, pathophysiology, and treatment prospects. In addition, we will delineate future avenues of research, including innovative translational opportunities.

Cancer-Associated Fibroblasts in Intrahepatic Cholangiocarcinoma: Insights into Origins, Heterogeneity, Lymphangiogenesis, and Peritoneal Metastasis

Intrahepatic cholangiocarcinoma (iCCA) denotes a rare, highly malignant, and heterogeneous class of primary liver adenocarcinomas exhibiting phenotypic characteristics of cholangiocyte differentiation. Among the distinctive pathological features of iCCA, one that differentiates the most common macroscopic subtype (eg, mass-forming type) of this hepatic tumor from conventional hepatocellular carcinoma is a prominent desmoplastic reaction manifested as a dense fibro-collagenous-enriched tumor stroma. Cancer-associated fibroblasts (CAFs) represent the most abundant mesenchymal cell type in the desmoplastic reaction. Although the protumor effects of CAFs in iCCA have been increasingly recognized, more recent cell lineage tracing studies, advanced single-cell RNA sequencing, and expanded biomarker analyses have provided new awareness into their ontogeny, as well as underscored their biological complexity as reflected by the presence of multiple subtypes. In addition, evidence supports CAFs' potential to display cancer-restrictive roles, including immunosuppression. However, CAFs also play important roles in facilitating metastasis, as exemplified by lymph node metastasis and peritoneal carcinomatosis, which are common in iCCA. Herein, the authors provide a timely appraisal of the origins and phenotypic and functional complexity of CAFs in iCCA, together with providing mechanistic insights into lymphangiogenesis and peritoneal metastasis relevant to this lethal human cancer.

Genetic, Epigenetic, and Microenvironmental Drivers of Cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive and heterogeneous malignancy of the biliary tree that carries a poor prognosis. Multiple features at the genetic, epigenetic, and microenvironmental levels have been identified to better characterize CCA carcinogenesis. Genetic alterations, such as mutations in IDH1/2, BAP1, ARID1A, and FGFR2, play significant roles in CCA pathogenesis, with variations across different subtypes, races/ethnicities, and causes. Epigenetic dysregulation, characterized by DNA methylation and histone modifications, further contributes to the complexity of CCA, influencing gene expression and tumor behavior. Furthermore, CCA cells exchange autocrine and paracrine signals with other cancer cells and the infiltrating cell types that populate the microenvironment, including cancer-associated fibroblasts and tumor-associated macrophages, further contributing to an immunosuppressive niche that supports tumorigenesis. This review explores the multifaceted genetic, epigenetic, and microenvironmental drivers of CCA. Understanding these diverse mechanisms is essential for characterizing the complex pathways of CCA carcinogenesis and developing targeted therapies to improve patient outcomes.

Unlocking the potential of chimeric antigen receptor T cell engineering immunotherapy: Long road to achieve precise targeted therapy for hepatobiliary pancreatic cancers

Innovative therapeutic strategies are urgently needed to address the ongoing global health concern of hepatobiliary pancreatic malignancies. This review summarizes the latest and most comprehensive research of chimeric antigen receptor (CAR-T) cell engineering immunotherapy for treating hepatobiliary pancreatic cancers. Commencing with an exploration of the distinct anatomical location and the immunosuppressive, hypoxic tumor microenvironment (TME), this review critically assesses the limitations of current CAR-T therapy in hepatobiliary pancreatic cancers and proposes corresponding solutions. Various studies aim at enhancing CAR-T cell efficacy in these cancers through improving T cell persistence, enhancing antigen specificity and reducing tumor heterogeneity, also modulating the immunosuppressive and hypoxic TME. Additionally, the review examines the application of emerging nanoparticles and biotechnologies utilized in CAR-T therapy for these cancers. The results suggest that constructing optimized CAR-T cells to overcome physical barrier, manipulating the TME to relieve immunosuppression and hypoxia, designing CAR-T combination therapies, and selecting the most suitable delivery strategies, all together could collectively enhance the safety of CAR-T engineering and advance the effectiveness of adaptive cell therapy for hepatobiliary pancreatic cancers.

Investigating the causal relationship between the plasma lipidome and cholangiocarcinoma mediated by immune cells: a mediation Mendelian randomization study

The plasma lipidome and immune cells are instrumental in shaping the health profile of an organism, and their influence on diseases is profound. However, the intricate interactions between cholangiocarcinoma (CCA) and these physiological components have yet to be comprehensively explored. Employing Mendelian randomization (MR), our study delved into the causal links among immune cells, the lipidome, and CCA. The research design meticulously considered both the direct associations and the mediating roles of immune cells within the complex interplay between the lipidome and CCA. Our analysis uncovered significant correlations between the levels of Sphingomyelin (d34:1), Phosphatidylcholine (0-16:0, 22:5) and Sterol ester (27:1/16:0) and CCA. Moreover, we have pinpointed various immune cells that play a mediating role in the impact of the lipidome on CCA. For example, Sphingomyelin (d34:1) can impact CCA through the IgD on IgD+ CD38- unswitched memory (unsw mem) B cell (B cell panel), IgD on unsw mem (B cell panel) and Naive CD4+ %CD4+ (maturation stages of T cell). The proportion of mediating effects further sheds light on the intricate interplay among the lipidome, immune cells, and their cumulative influence on CCA. Our study illuminates the intricate relationship among the lipidome, immune cells, and CCA. These findings suggest that the lipidome could serve as a promising and potentially effective therapeutic target in the treatment of CCA.

PPIH is a novel diagnostic biomarker associated with immune infiltration in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CHOL) is the second most common primary liver malignancy, characterized by high aggressiveness and heterogeneity. It is typically diagnosed at an advanced stage, leading to a poor prognosis. Although Peptidyl Proline Isomerase H (PPIH) has been implicated in various tumors, its role in CHOL remains unexplored. This study aims to investigate the diagnostic value and potential function of PPIH in CHOL.

METHODS

We analyzed the expression levels, prognostic significance, and diagnostic efficiency of PPIH in CHOL using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets, coupled with gene enrichment analyses. The CIBERSORT database was employed to assess the correlation between PPIH expression and immune cell infiltration in CHOL. Additionally, immunohistochemical experiments were conducted to validate PPIH expression levels in CHOL tissues and to explore its correlation with TP53 gene mutations.

RESULTS

Our findings indicate that overexpression of PPIH mRNA in CHOL is associated with poor prognosis, with increased PPIH protein levels observed in CHOL tissues. Furthermore, PPIH expression showed a positive correlation with TP53 mutations. PPIH demonstrated strong diagnostic value for CHOL. Moreover, PPIH may influence tumor progression through its involvement in cell cycle regulation and spliceosome pathways, and is associated with immune cell infiltration levels.

CONCLUSION

The results of this study suggest that PPIH is a potential novel biomarker with significant diagnostic value for patients with CHOL. PPIH may also play a role in modulating the immune microenvironment, contributing to poor prognosis.

Biomarkers for the Evaluation of Immunotherapy in Patients with Cholangiocarcinoma

Cholangiocarcinoma is a rare primary liver cancer with poor prognosis, due to the advanced stage at the time of diagnosis and limited therapeutic options, with poor response. Chemotherapy remains the standard first-line treatment, but the advent of immunotherapy has recently induced promising results. Given the fact that diagnosis frequency is increasing nowadays and the survival rate remains very low, it is crucial to recognize patients who are suitable for immunotherapy and will have the best response. Different types of biomarkers, such as interleukins, exosomes, mi-RNA, ctDNA, and gene mutations, have been studied for their feasibility, not only for the early diagnosis of biliary tract cancer but also for the determination of responsiveness in treatment. Less frequently, these studies focus on finding and observing biomarkers in patients who receive immunotherapy. This review aims to summarize current knowledge of existing/promising biomarkers in patients with unresectable or metastatic cholangiocarcinoma, treated with immunotherapy as monotherapy, or combined with chemotherapy.

Prognostic implications of tumor histology and microenvironment in surgically resected intrahepatic cholangiocarcinoma: a single institutional experience

Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive malignant neoplasm. Certain histologic features and the tumor microenvironment may impact disease progression. We aim to characterize the clinicopathologic features of ICC to identify prognostic factors. A total of 50 surgically resected ICC (partial or transplant) cases were analyzed. The cohort included 26 men and 24 women with a median age of 62 years. Eighteen (36%) cases were multifocal ICC with a mean largest tumor size of 6.5 cm. Neoadjuvant and adjuvant chemotherapy was done in eight (16%) and 33 (66%) patients, respectively. Histologically, 42 (84%) were small duct type, seven (14%) large duct type, and one mixed (2%). Thirty (60%) cases showed lymphovascular invasion (LVI) and 11 (22%) with perineural invasion (PNI). Twenty-eight (56%) cases demonstrated dense intratumoral hyaline fibrosis and 18 (36%) with tumor necrosis, each ≥ 10% tumor volume. On follow-up, 35 (70%) patients died of disease after a median disease-specific survival (DSS) of 21 months. Univariate analysis revealed that hyaline fibrosis and adjuvant chemotherapy were associated with better DSS, while tumor size, multifocality, necrosis, and peritumoral neutrophil to lymphocyte ratio were associated with worse DSS. In contrast, age, sex, small vs. large duct types, LVI, and individual inflammatory cell counts were not significant prognostic factors. In summary, ICC is a heterogeneous malignancy with variable clinical courses associated with tumor burden, histology, and microenvironment. Targeting specific components within the tumor microenvironments may be a promising approach for treatment in the future.

The importance of preclinical models for cholangiocarcinoma drug discovery

INTRODUCTION

Biliary tract cancer (BTC) comprises a clinically diverse and genetically heterogeneous group of tumors along the intra- and extrahepatic biliary system (intrahepatic and extrahepatic cholangiocarcinoma) and gallbladder cancer with the common feature of a poor prognosis, despite increasing molecular knowledge of associated genetic aberrations and possible targeted therapies. Therefore, the search for even more precise and individualized therapies is ongoing and preclinical tumor models are central to the development of such new approaches.

AREAS COVERED

The models described in the current review include simple and advanced in vitro and in vivo models, including cell lines, 2D monolayer, spheroid and organoid cultures, 3D bioprinting, patient-derived xenografts, and more recently, machine-perfusion platform-based models of resected liver specimens. All these models have individual advantages, disadvantages and limitations that need to be considered depending on the desired application.

EXPERT OPINION

In addition to potential cost limitations, availability of BTC cell types, time required for model establishment and growth success rate, the individual models differently reflect relevant characteristics such as tumor heterogeneity, spatial tumor-stroma microenvironment interactions, metabolic and nutritional gradients and immunological interactions. Therefore, a consequent combination of different models may be required to improve clinical study outcomes by strengthening the preclinical data basis.

Exploring the effects of gut microbiota on cholangiocarcinoma progression by patient-derived organoids

BACKGROUND

Recent research indicates a role of gut microbiota in development and progression of life-threatening diseases such as cancer. Carcinomas of the biliary ducts, the so-called cholangiocarcinomas, are known for their aggressive tumor biology, implying poor prognosis of affected patients. An impact of the gut microbiota on cholangiocarcinoma development and progression is plausible due to the enterohepatic circulation and is therefore the subject of scientific debate, however evidence is still lacking. This review aimed to discuss the suitability of complex cell culture models to investigate the role of gut microbiota in cholangiocarcinoma progression.

MAIN BODY

Clinical research in this area is challenging due to poor comparability of patients and feasibility reasons, which is why translational models are needed to understand the basis of tumor progression in cholangiocarcinoma. A promising approach to investigate the influence of gut microbiota could be an organoid model. Organoids are 3D cell models cultivated in a modifiable and controlled condition, which can be grown from tumor tissue. 3D cell models are able to imitate physiological and pathological processes in the human body and thus contribute to a better understanding of health and disease.

CONCLUSION

The use of complex cell cultures such as organoids and organoid co-cultures might be powerful and valuable tools to study not only the growth behavior and growth of cholangiocarcinoma cells, but also the interaction with the tumor microenvironment and with components of the gut microbiota.

Infiltrating T lymphocytes and tumor microenvironment within cholangiocarcinoma: immune heterogeneity, intercellular communication, immune checkpoints

Cholangiocarcinoma is the second most common primary liver cancer, and its global incidence has increased in recent years. Radical surgical resection and systemic chemotherapy have traditionally been the standard treatment options. However, the complexity of cholangiocarcinoma subtypes often presents a challenge for early diagnosis. Additionally, high recurrence rates following radical treatment and resistance to late-stage chemotherapy limit the benefits for patients. Immunotherapy has emerged as an effective strategy for treating various types of cancer, and has shown efficacy when combined with chemotherapy for cholangiocarcinoma. Current immunotherapies targeting cholangiocarcinoma have predominantly focused on T lymphocytes within the tumor microenvironment, and new immunotherapies have yielded unsatisfactory results in clinical trials. Therefore, it is essential to achieve a comprehensive understanding of the unique tumor microenvironment of cholangiocarcinoma and the pivotal role of T lymphocytes within it. In this review, we describe the heterogeneous immune landscape and intercellular communication in cholangiocarcinoma and summarize the specific distribution of T lymphocytes. Finally, we review potential immune checkpoints in cholangiocarcinoma.

The Immune Landscape and Its Potential for Immunotherapy in Advanced Biliary Tract Cancer

Biliary tract cancers (BTC) are a highly heterogeneous group of cancers at the genomic, epigenetic and molecular levels. The vast majority of patients initially present at an advanced (unresectable) disease stage due to a lack of symptoms and an aggressive tumour biology. Chemotherapy has been the mainstay of treatment in patients with advanced BTC but the survival outcomes and prognosis remain poor. The addition of immune checkpoint inhibitors (ICI) to chemotherapy have shown only a marginal benefit over chemotherapy alone due to the complex tumour immune microenvironment of these cancers. This review appraises our current understanding of the immune landscape of advanced BTC, including emerging transcriptome-based classifications, highlighting the mechanisms of immune evasion and resistance to ICI and their therapeutic implications. It describes the shifting treatment paradigm from traditional chemotherapy to immunotherapy combinations as well as the potential biomarkers for predicting response to ICI.

New Relevant Evidence in Cholangiocarcinoma Biology and Characterization

Among solid tumors, cholangiocarcinoma (CCA) emerges as one of the most difficult to eradicate. The silent and asymptomatic nature of this tumor, particularly in its early stages, as well as the high heterogeneity at genomic, epigenetic, and molecular levels delay the diagnosis, significantly compromising the efficacy of current therapeutic options and thus contributing to a dismal prognosis. Extensive research has been conducted on the molecular pathobiology of CCA, and recent advances have been made in the classification and characterization of new molecular targets. Both targeted therapy and immunotherapy have emerged as effective and safe strategies for various types of cancers, demonstrating potential benefits in advanced CCA. Furthermore, the deeper comprehension of the cellular and molecular components in the tumor microenvironment (TME) has opened up possibilities for new innovative treatment methods. This review discusses recent evidence in the characterization and molecular biology of CCA, highlighting novel possible druggable targets.

Immunobiology of biliary tract cancer and recent clinical findings in approved and upcoming immune checkpoint inhibitors

INTRODUCTION

Recently, immunotherapy has offered new hope for treating biliary tract cancer (BTC). However, several issues are to be considered, including the lack of validated predictive biomarkers that could help to identify patient groups which are most likely to benefit from such therapeutic approaches.

AREAS COVERED

In the current article, we will provide an overview of recent results and ongoing and future research directions of immunotherapy in BTC, with a special focus on recently published, practice-changing data, and ongoing active and recruiting clinical trials.

EXPERT OPINION

At this moment, dozens of clinical trials in phases I to III are evaluating the role of cancer immunotherapy in this setting, with the hope of adding more therapeutic options for BTC patients. Future research must focus on the development of novel agents and combinations, but the validation of biomarkers remains an urgent need. As more research results emerge, novel combinatorial strategies are destined to further transform the treatment paradigm for this heterogeneous and aggressive tumor type.

Identification of PANoptosis-relevant subgroups and predicting signature to evaluate the prognosis and immune landscape of patients with biliary tract cancer

BACKGROUND

This study conducted molecular subtyping of biliary tract cancer patients based on 19 PANoptosis-related gene signatures.

METHODS

Through consensus clustering, patients were categorized into two subtypes, A and B. By integrating multi-omics data and clinical information from different cohorts, we elucidated the association between different subtypes of biliary tract cancer and patient prognosis, which correlated with the immune infiltration characteristics of patients.

RESULTS

LASSO regression analysis was performed on the 19 gene signatures, and we constructed and validated a 9-gene risk score prognostic model that accurately predicts the overall survival rate of different biliary tract cancer patients. Additionally, we developed a predictive nomogram demonstrating the clinical utility and robustness of our model. Further analysis of the risk score-based immune landscape highlighted potential associations with immune cell infiltration, chemotherapy, and immune therapy response.

CONCLUSION

Our study provides valuable insights into personalized treatment strategies for biliary tract cancer, which are crucial for improving patient prognosis and guiding treatment decisions in clinical practice.

Expression and molecular insights of lima1 in cholangiocarcinoma

Lim Domain and Actin Binding protein1 (lima1) influence cancer cell function. Thus far, functional role of lima1 in cholangiocarcinoma remains unknown. We used public databases, in vitro experiments, and multi-omics analysis to investigate the Lima1 in cholangiocarcinoma. Our results showed that lima1 expression is significantly upregulated and high levels of lima1 are significantly associated with vascular invasion in cholangiocarcinoma. Furthermore, lima1 knocking out inhibits the RBE cell invasion. Multi-omics data suggest that lima1 affect a broad spectrum of cancer related pathways, promoting tumor progression and metastatic ability in cholangiocarcinoma. This study provides insights into molecular associations of lima1 with tumorigenesist and establishes a preliminary picture of the correlation network in cholangiocarcinoma.

Immunohistochemical basis for FAP as a candidate theranostic target across a broad range of cholangiocarcinoma subtypes

Purpose

The aims of this study were to evaluate and compare fibroblast activation protein (FAP) expression and localization in surgically resected cholangiocarcinoma (CCA), primary and metastatic hepatocellular carcinoma (HCC), hepatocellular adenoma (HCA), and focal nodular hyperplasia (FNH), and to identify any association between CCA clinical or pathologic features and FAP expression.

Materials and methods

FAP immunostaining from surgically resected CCA (N = 58), primary intrahepatic and extrahepatic metastatic HCC (N = 148), HCA (N26), and FNH (N = 19) was scored (negative, weak positive, moderate positive or strong positive) from tissue microarrays. FAP expression was compared between groups. CCA FAP expression was compared to clinical and tumor pathology features.

Results

Moderate-strong FAP expression in the tumor stroma was present in 93.1% of CCA, 60.7% of extrahepatic metastatic HCC, 29.6% of primary HCC, 21.1% of FNH, and 11.6% of HCA. Moderate-strong FAP expression in tumor stroma was significantly more prevalent in CCA than HCC (p < 0.001), metastatic HCC (p = 0.005), HCA (p < 0.001) and FNH (p < 0.001). FAP was expressed in the stroma of all but one CCA (1.7%), and FAP expression in CCA tumor stroma was not associated with any clinical or tumor pathology features (p > 0.05, all).

Conclusion

FAP is expressed in the stroma of a high proportion (93%) of primary CCA independent of patient clinical or tumor pathology features. As such, these data provide the tissue basis for systematically evaluating FAP as a theranostic target across a broad range of CCA subtypes.

Unveiling the prognostic role of blood inflammatory indexes in a retrospective cohort of patients undergoing liver resection for intrahepatic cholangiocarcinoma

BACKGROUND

Systemic inflammation is relevant in intrahepatic cholangiocarcinoma (iCCA), but controversial results exist on the prognostic role of inflammatory indexes and their correlation with tumor microenvironment. The authors aimed to explore the biological and prognostic values of these indexes.

MATERIALS AND METHODS

A retrospective cohort study involving iCCA patients who underwent hepatic resection between 2010 and 2021 was conducted. The neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and clinic-pathological factors were recorded. Immune-cell subpopulations, isolated from surgical specimens, were analyzed by flow cytometry. NLR and LMR cut-offs were calculated by X-Tile software. Linear regression, Kaplan-Meier, and Cox regression analyses were conducted.

RESULTS

A total of 101 iCCA patients were considered. NLR ≥3.83 and LMR <2.28 correlated with worse survival. Patients were divided into groups: 67 (66.3%) in the low-risk and 34 (33.7%) in the high-risk (having at least one worse prognostic ratio). The 5-year overall survival was 49.8 and 18.9% for low- and high-risk groups, respectively ( P =0.003). An elevated CA19-9 in the high-risk group gives 2.148 HR (95% CI: 1.060-4.349) of mortality and 2.182 HR (95% CI: 1.206-3.948) of disease recurrence. Flow cytometry analysis of 20 surgical specimens highlighted that NLR was associated with tumor-derived NLR ( P =0.026) and LMR with tumor-infiltrating lymphocytes ( P =0.002). In a subset of five high-risk vs five low-risk patients, T-cell evaluation showed a higher prevalence of CD4+ compared to CD8+ cells in the high-risk group (78.5 vs. 21.5%, P <0.0001). Conversely, low-risk patients demonstrated a noteworthy infiltration of CD8+ cells compared to the high-risk group (21.5 vs. 48.7%, P =0.037).

CONCLUSIONS

The combination of blood inflammatory indexes determined two survival-risk profiles. The correlation between the blood scores and the iCCA microenvironment suggests a link between immune-cell infiltration and the risk group. These findings open the possibility of patient stratification with the chance to identify subgroups suitable for dedicated follow-up and targeted immuno-chemotherapy protocols.

Prognostic impact of the tumour microenvironment in intrahepatic cholangiocarcinoma: identification of a peritumoural fibro-immune interface

The tumour microenvironment (TME) of intrahepatic cholangiocarcinoma (iCCA) is complex and plays a role in prognosis and resistance to treatments. We aimed to decipher the iCCA TME phenotype using multiplex sequential immunohistochemistry (MS-IHC) to investigate which cell types and their spatial location may affect its prognosis. This was a retrospective study of 109 iCCA resected samples. For all cases, we used an open-source software to analyse a panel of markers (αSMA, FAP, CD8, CD163) by MS-IHC for characterize the different TME cells and their location. RNA sequencing was performed to determine the main iCCA transcriptomic classes. The association of the TME composition with overall survival (OS) was assessed by univariate and multivariate analyses. A high proportion of activated fibroblasts (FAP +) was significantly associated with poor OS (HR = 2.33, 95%CI = 1.43-3.81, p = 0.001). CD8 T lymphocytes excluded from the epithelial compartment were significantly associated with worse OS (HR = 1.86, 95% CI = 1.07-3.22, p = 0.014). The combination of a high proportion of FAP + fibroblasts and CD8 T lymphocytes excluded from the epithelial compartment, observed in 21 cases (19%), was significantly associated with poor OS on univariate (HR = 2.49, 95% CI = 1.44-4.28, p = 0.001) and multivariate analyses (HR = 2.77, 95% CI = 1.56-4.92, p < 0.001). In these cases, CD8 T lymphocytes were predominantly located at the tumour/non-tumour interface (19/21, 90%), and an association with the transcriptomic inflammatory stroma class was observed (10/21, 48%). Our results confirm the TME prognostic role in iCCA, highlighting the impact in the process of spatial heterogeneity, especially cell colocalization of immune and fibroblastic cells creating a peritumoural fibro-immune interface.

Identification of molecular subtypes based on bile acid metabolism in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma is a highly heterogeneous tumor with bile acid metabolism involving in its development. The aim of this study was to characterize bile acid metabolism and identify specific subtypes to better stratify cholangiocarcinoma patients for individualized treatment and prognostic assessment.

METHODS

A total of 30 bile acids were quantified using the ultra-performance liquid chromatography tandem mass spectrometry. Using Consensus clustering, the molecular subtypes related to bile acid metabolism were identified. The prognosis, clinicopathologic characteristics, immune landscape, and therapeutic response were compared between these subtypes. The single-cell RNA sequencing (scRNA-seq) analysis and preliminary cell experiment were also conducted to verify our findings.

RESULTS

The altered bile acid profile and genetic variation of bile acid metabolism-related genes in cholangiocarcinoma were demonstrated. The cholangiocarcinoma was categorized into bile acid metabolism-active and -inactive subtypes with different prognoses, clinicopathologic characteristics, tumor microenvironments (TME) and therapeutic responses. This categorization was reproducible and predictable. Specifically, the bile acid metabolism-active subtype showed a poor prognosis with an immunosuppressive microenvironment and an inactive response to immunotherapy, while the bile acid metabolism-inactive subtype showed the opposite characteristics. Moreover, the scRNA-seq revealed that immunotherapy altered bile acid metabolism in TME of cholangiocarcinoma. Finally, a prognostic signature related to bile acid metabolism was developed, which exhibited strong power for prognostic assessment of cholangiocarcinoma. Consistently, these results were verified by immunohistochemistry, cell proliferation, migration, and apoptosis assays.

CONCLUSION

In conclusion, a novel cholangiocarcinoma classification based on bile acid metabolism was established. This classification was significant for the estimation of TME and prognosis.

Prevalence of Chronic Liver Disease in Cholangiocarcinoma: A Meta-Analysis

BACKGROUND AND AIMS

Chronic liver disease is a known risk factor for cholangiocarcinoma (CCA), but the proportion of people with CCA who have concurrent chronic liver disease is unclear. We aimed to evaluate the prevalence of chronic liver diseases in people with CCA.

METHODS

In this single-arm meta-analysis, we searched MEDLINE and EMBASE from inception to August 10, 2024, for articles in English containing data for CCA with and without chronic liver diseases. Data were pooled to obtain the prevalence of different chronic liver diseases, with further stratification by geographical location and tumor location.

RESULTS

In total, 118,068 individuals diagnosed with CCA were included, of whom 16,771 had chronic liver diseases. A pooled analysis of 109 studies determined that the prevalence of chronic liver disease was 25.23% (95% confidence interval [CI], 20.82%-30.23%; I2 = 99.0%), and 10.21% (7.75%-13.35%; I2 = 98.6%) of CCA patients had cirrhosis. Chronic liver diseases were associated more with intrahepatic CCAs, compared with extrahepatic CCAs (relative risk, 2.46; 95% CI, 2.37-2.55; P < .0001). This was observed across all etiologies of liver disease, except for primary sclerosing cholangitis, which was associated with extrahepatic CCAs (relative risk, 0.49; 95% CI, 0.43-0.57; P < .0001).

CONCLUSIONS

Around 1 in 4 people with CCA have chronic liver diseases, and 1 in 10 have cirrhosis.

Targeting cancer-associated fibroblasts/tumor cells cross-talk inhibits intrahepatic cholangiocarcinoma progression via cell-cycle arrest

BACKGROUND

Cancer-associated fibroblasts (CAFs), mainly responsible for the desmoplastic reaction hallmark of intrahepatic Cholangiocarcinoma (iCCA), likely have a role in tumor aggressiveness and resistance to therapy, although the molecular mechanisms involved are unknown. Aim of the study is to investigate how targeting hCAF/iCCA cross-talk with a Notch1 inhibitor, namely Crenigacestat, may affect cancer progression.

METHODS

We used different in vitro models in 2D and established new 3D hetero-spheroids with iCCA cells and human (h)CAFs. The results were confirmed in a xenograft model, and explanted tumoral tissues underwent transcriptomic and bioinformatic analysis.

RESULTS

hCAFs/iCCA cross-talk sustains increased migration of both KKU-M213 and KKU-M156 cells, while Crenigacestat significantly inhibits only the cross-talk stimulated migration. Hetero-spheroids grew larger than homo-spheroids, formed by only iCCA cells. Crenigacestat significantly reduced the invasion and growth of hetero- but not of homo-spheroids. In xenograft models, hCAFs/KKU-M213 tumors grew significantly larger than KKU-M213 tumors, but were significantly reduced in volume by Crenigacestat treatment, which also significantly decreased the fibrotic reaction. Ingenuity pathway analysis revealed that genes of hCAFs/KKU-M213 but not of KKU-M213 tumors increased tumor lesions, and that Crenigacestat treatment inhibited the modulated canonical pathways. Cell cycle checkpoints were the most notably modulated pathway and Crenigacestat reduced CCNE2 gene expression, consequently inducing cell cycle arrest. In hetero-spheroids, the number of cells increased in the G2/M cell cycle phase, while Crenigacestat significantly decreased cell numbers in the G2/M phase in hetero but not in homo-spheroids.

CONCLUSIONS

The hCAFs/iCCA cross-talk is a new target for reducing cancer progression with drugs such as Crenigacestat.

Septin 9 expression regulates 'don't eat me' signals and identifies an immune-epithelial class of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a highly heterogeneous and aggressive liver cancer with limited therapeutic options. Precise classification and immunotherapy are perspectives to improve the treatments. We reported the role of septin 9 in apico-basal polarity and epithelial-to-mesenchymal transition (EMT). Here, we aim to elucidate its role in iCCA. We analyzed single-cell transcriptomes from human iCCA tumor cells based on phenotype and cell state. Knockdown of the septin 9 gene (SEPT9) was done using small interfering RNA (siRNA); interferon-γ (IFN-γ) stimulation was performed using different CCA cells; gene expressions were analyzed by reverse transcription and real-time PCR analysis (RT-qPCR); and immunofluorescence, immunoblotting, and flow cytometry were performed to assess the expression of proteins. The differential distributions of SEPT9 and vimentin (VIM) gene expressions allowed us to define specific cellular trajectories of malignant cells and thus identified distinct clusters of iCCA cells. One cluster was enriched in VIM and extracellular-matrix (ECM) remodeling molecules, and another had high expression of SEPT9 and genes from the 'don't eat me' signal involved in immune escape. This antagonism between SEPT9 and VIM was confirmed by in vitro experiments. Notably, SEPT9 and 'don't eat me' gene expressions were inversely correlated to those of vimentin and the EMT markers. SEPT9 expression was upregulated by IFN-γ and SEPT9 knockdown decreased expression of 'don't eat me' signal genes and increased expression of mesenchymal markers. Cancer Cell Line Encyclopedia (CCLE) transcriptome database analyses confirmed that iCCA cells enriched in septin 9 exhibit epithelial-like features. This study revealed septin 9 as a cytoskeleton element of iCCA epithelial-like cells and a regulator of the immune system response. It also brings new insights into the enigmatic relationship between EMT and immune response. Notably, we decoded a potential mechanism that could sensitize patients to immunotherapies.

Radiomics of Intrahepatic Cholangiocarcinoma and Peritumoral Tissue Predicts Postoperative Survival: Development of a CT-Based Clinical-Radiomic Model

BACKGROUND

For many tumors, radiomics provided a relevant prognostic contribution. This study tested whether the computed tomography (CT)-based textural features of intrahepatic cholangiocarcinoma (ICC) and peritumoral tissue improve the prediction of survival after resection compared with the standard clinical indices.

METHODS

All consecutive patients affected by ICC who underwent hepatectomy at six high-volume centers (2009-2019) were considered for the study. The arterial and portal phases of CT performed fewer than 60 days before surgery were analyzed. A manual segmentation of the tumor was performed (Tumor-VOI). A 5-mm volume expansion then was applied to identify the peritumoral tissue (Margin-VOI).

RESULTS

The study enrolled 215 patients. After a median follow-up period of 28 months, the overall survival (OS) rate was 57.0%, and the progression-free survival (PFS) rate was 34.9% at 3 years. The clinical predictive model of OS had a C-index of 0.681. The addition of radiomic features led to a progressive improvement of performances (C-index of 0.71, including the portal Tumor-VOI, C-index of 0.752 including the portal Tumor- and Margin-VOI, C-index of 0.764, including all VOIs of the portal and arterial phases). The latter model combined clinical variables (CA19-9 and tumor pattern), tumor indices (density, homogeneity), margin data (kurtosis, compacity, shape), and GLRLM indices. The model had performance equivalent to that of the postoperative clinical model including the pathology data (C-index of 0.765). The same results were observed for PFS.

CONCLUSIONS

The radiomics of ICC and peritumoral tissue extracted from preoperative CT improves the prediction of survival. Both the portal and arterial phases should be considered. Radiomic and clinical data are complementary and achieve a preoperative estimation of prognosis equivalent to that achieved in the postoperative setting.

Macrophage-derived exosomal miR-155 regulating hepatocyte pyroptosis in MAFLD

Background

Previous studies have shown that pyroptosis in hepatocyte is essential for the development of MAFLD. Growing evidence has shown that exosomal miRNAs-mediated communication between inflammatory cells and hepatocyte is an important link in MAFLD. In the present study, we aim to elucidate whether macrophage-derived exosomal miRNAs contribute to the hepatocyte pyroptosis in the pathophysiological process of MAFLD.

Methods

The effects of hepatocyte pyroptosis were investigated in an HFD-induced MAFLD mouse model and in the liver tissues from patients with MAFLD using immunohistochemistry, real-time PCR, Western blotting, and luciferase reporter assay, among other techniques. MiR-155 inhibitor tail injections and AAV-FoxO3a-GFP were also administered to respectively inhibit or overexpress its expression in an HFD-induced MAFLD mouse model.

Results

Hepatocyte pyroptosis was heightened in the liver tissue of patients with MAFLD or HFD-induced MAFLD mouse. Importantly, treatment with a caspase-1 inhibitor or overexpression of FoxO3a reversed this trend. Our study also demonstrated that miR-155 expression and the number of infiltrated macrophages were increased, and knockdown of miR-155 attenuated hepotocyte pyroptosis and liver fibrosis in HFD-induced mouse. In addition, we demonstrated that macrophage-derived exosomal miR-155 was transferred to hepatocytes, leading to hepatocyte pyroptosis in MAFLD mouse. Furthermore, blockade of exosome secretion improved hepotocyte pyroptosis and liver fibrosis in HFD-induced mouse. On the contrary, macrophage-derived exosomal miR-155 worsened hepotocyte pyroptosis. Moreover, we found that miR-155 promoted hepatocyte pyroptosis in MAFLD by down-regulating FoxO3a.

Conclusions

Taken together, our results demonstrated that macrophage-derived exosomal miR-155 promotes hepatocyte pyroptosis and liver fibrosis in MAFLD.

Emerging biomarkers for immunotherapy response in biliary tract cancers: a comprehensive review of immune checkpoint inhibitor strategies

Biliary tract cancers (BTCs) have rising incidence and mortality rates. Chemotherapy's limited efficacy has led to exploring new treatments like immunotherapy. which offers modest benefits. Moreover, the identification of reliable predictive biomarkers for immune checkpoint therapy in BTCs remains elusive, hindering personalized treatment strategies. This review provides an overview of the current landscape of emerging biomarkers for immunotherapy response in BTCs. We discuss the incremental benefits of combination therapy and the evolving role of immunotherapy in managing advanced BTC. Additionally, we highlight the need for robust predictive biomarkers to optimize treatment outcomes and foster a more individualized approach to patient care. We aim to identify promising research avenues and strategies to enhance therapeutic efficacy and patient survival in BTCs.

Strategies for treating the cold tumors of cholangiocarcinoma: core concepts and future directions

Cholangiocarcinoma (CCA) is a rare type of digestive tract cancer originating from the epithelial cells of the liver and biliary tract. Current treatment modalities for CCA, such as chemotherapy and radiation therapy, have demonstrated limited efficacy in enhancing survival rates. Despite the revolutionary potential of immunotherapy in cancer management, its application in CCA remains restricted due to the minimal infiltration of immune cells in these tumors, rendering them cold and unresponsive to immune checkpoint inhibitors (ICIs). Cancer cells within cold tumors deploy various mechanisms for evading immune attack, thus impeding clinical management. Recently, combination immunotherapy has become increasingly essential to comprehend the mechanisms underlying cold tumors to enhance a deficient antitumor immune response. Therefore, a thorough understanding of the knowledge on the combination immunotherapy of cold CCA is imperative to leverage the benefits of immunotherapy in treating patients. Moreover, gut microbiota plays an essential role in the immunotherapeutic responses in CCA. In this review, we summarize the current concepts of immunotherapy in CCA and clarify the intricate dynamics within the tumor immune microenvironment (TIME) of CCA. We also delve into the evasion mechanisms employed by CCA tumors against the anti-tumor immune responses. The context of combination immunotherapies in igniting cold tumors of CCA and the critical function of gut microbiota in prompting immune responses have also been annotated. Furthermore, we have proposed future directions in the realm of CCA immunotherapy, aiming to improve the clinical prognosis of CCA patients.

Overcoming treatment resistance in cholangiocarcinoma: current strategies, challenges, and prospects

Significant advancements in our understanding and clinical treatment of cholangiocarcinoma (CCA) have been achieved over the past 5 years. Groundbreaking studies have illuminated the immune landscape and pathological characteristics of the tumor microenvironment in CCA. The development of immune- and metabolism-based classification systems has enabled a nuanced exploration of the tumor microenvironment and the origins of CCA, facilitating a detailed understanding of tumor progression modulation. Despite these insights, targeted therapies have not yet yielded satisfactory clinical results, highlighting the urgent need for innovative therapeutic strategies. This review delineates the complexity and heterogeneity of CCA, examines the current landscape of therapeutic strategies and clinical trials, and delves into the resistance mechanisms underlying targeted therapies. Finally, from a single-cell and spatial transcriptomic perspective, we address the challenge of therapy resistance, discussing emerging mechanisms and potential strategies to overcome this barrier and enhance treatment efficacy.

Knockdown of long noncoding RNA AL161431.1 inhibits malignant progression of cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is one of the most deadly cancers in the world. It usually has a bad prognosis and is challenging to identify in its early stages. Long noncoding RNAs (lncRNAs) have been shown in an increasing number of studies to be important in the control of signaling pathways, cell behaviors, and epigenetic modification that contribute to the growth of tumors. The purpose of this work was to examine the relationship between CCA and lncRNA AL161431.1.

METHODS

Using TCGA clinical survival data, we evaluated the association between AL161431.1 expression and patient prognosis. Using the program cluster Profiler R, enrichment analysis was performed. Additionally, the association between immune cell infiltration and AL161431.1 expression was evaluated by a review of the TCGA database. Next, to ascertain if AL161431.1 influences tumor growth, migration, and invasion in CCA, functional in vitro assays were conducted. Quantitative real-time polymerase chain reaction (qPCR) was employed to gauge AL161431.1 expression levels in CCA cells. Western blot was used to measure protein levels.

RESULTS

In CCA, AL161431.1 was extremely expressed. The patients in the high-risk group had a significantly poorer overall survival (OS) than the patients in the low-risk group. A more thorough look at the TCGA data showed a relationship between high expression levels of AL161431.1 and increased infiltration of T cells, T helper cells, and NK CD56dim cells. Furthermore, AL161431.1 knockdown in CCA cells impeded invasion, migration, and proliferation and also lowered the expression of phosphorylated Smad2/Smad3 to restrain the TGFβ/SMAD signaling pathway.

CONCLUSIONS

Our results indicate that the lncRNA AL161431.1 activates the TGFβ/SMAD signaling pathway to enhance CCA development and metastasis. AL161431.1 could be a novel target for cholangiocarcinoma treatment or a diagnostic marker.

Multiplexed immunohistochemical analysis of the immune microenvironment of biliary tract cancers pre- & post-neoadjuvant chemotherapy: case series

Background

Neoadjuvant chemotherapy (NACT) is increasingly being used in the management of locally advanced biliary tract cancer (BTC). The evidence suggests a contributing role of tumor infiltrating immune cells in the prognosis and response. We set out to characterize immune modulation of tumor immune microenvironment in BTC following NACT.

Case Description

Patients with BTC who underwent diagnostic biopsy, then NACT then resection between 2014-2018 were identified. Multiplexed immunohistochemical consecutive staining on single slide (MICSSS) analysis was performed with a series of immune markers to characterize T-cells, immune checkpoints etc. on pre- & post-NACT tumor tissue. Density was calculated for each marker. The final analysis included five patients. Median age was 48 (range, 41-56) years, with 4 female, 4 intrahepatic cholangiocarcinoma and 1 gallbladder. All patients received gemcitabine/cisplatin as NACT (median of 5 cycles). Median time from diagnosis to surgery was 4.3 (range, 1.4-7.8) months. All patients were mismatch repair proficient (pMMR). NACT on average produced a depletion of all immune markers. Given small sample size, each patient was considered their own control and changes in mean cell densities post-NACT were calculated. Patient #2 with a 40-fold increase in PD-L1 expression & 5-fold decrease in CD8:FOXP3 ratio after NACT notably had the shortest disease-free interval (DFI). Patient #3 with the longest DFI had the largest increase in CD8:FOXP3 by about 8-fold with a decrease in PD-L1.

Conclusions

Preliminary results suggest NACT may differentially modulate various compartments of the immune tumor contexture despite overall cell depletion. Future studies should focus on strategies to expand immune modulation of tumor microenvironment, including immune-oncology agents to augment the effects of chemotherapy.

Tumor-infiltrating T lymphocytes: A promising immunotherapeutic target for preventing immune escape in cholangiocarcinoma

Cholangiocarcinoma (CCA) is becoming more common and deadly worldwide. Tumor-infiltrating T cell subtypes make distinct contributions to the immune system; collectively, they constitute a significant portion of the tumor microenvironment (TME) in CCA. By secreting cytokines and other chemicals, regulatory T cells (Tregs) decrease activated T cell responses, acting as immunosuppressors. Reduced CD8+ T cell activation results in stimulating programmed death-1 (PD-1), which undermines the immunological homeostasis of T lymphocytes. On the other hand, cancer cells are eliminated by activated cytotoxic T lymphocyte (CTL) through the perforin-granzyme or Fas-FasL pathways. Th1 and CTL immune cell infiltration into the malignant tumor is also facilitated by γδ T cells. A higher prognosis is typically implied by CD8+ T cell infiltration, and survival is inversely associated with Treg cell density. Immune checkpoint inhibitors, either singly or in combination, provide novel therapeutic strategies for CCA immunotherapy. Furthermore, it is anticipated that immunotherapeutic strategies-such as the identification of new immune targets, combination treatments involving several immune checkpoint inhibitors, and chimeric antigen receptor-T therapies (CAR-T)-will optimize the effectiveness of anti-CCA treatments while reducing adverse effects.

A Review of Type 1 and Type 2 Intraductal Papillary Neoplasms of the Bile Duct

Intraductal papillary neoplasm of the bile duct (IPNB) is a heterogeneous disease similar to intraductal papillary mucinous neoplasm of the pancreas. These lesions have been recognized as one of the three major precancerous lesions in the biliary tract since 2010. In 2018, Japanese and Korean pathologists reached a consensus, classifying IPNBs into type l and type 2 IPNBs. IPNBs are more prevalent in male patients in East Asia and are closely related to diseases such as cholelithiasis and schistosomiasis. From a molecular genetic perspective, IPNBs exhibit early genetic variations, and different molecular pathways may be involved in the tumorigenesis of type 1 and type 2 IPNBs. The histological subtypes of IPNBs include gastric, intestinal, pancreaticobiliary, or oncocytic subtypes, but type 1 IPNBs typically exhibit more regular and well-organized histological features than type 2 IPNBs and are more commonly found in the intrahepatic bile ducts with abundant mucin. Due to the rarity of these lesions and the absence of specific clinical and laboratory features, imaging is crucial for the preoperative diagnosis of IPNB, with local bile duct dilation and growth along the bile ducts being the main imaging features. Surgical resection remains the optimal treatment for IPNBs, but negative bile duct margins and the removal of lymph nodes in the hepatic hilum significantly improve the postoperative survival rates for patients with IPNBs.

Long-term oncological results of percutaneous radiofrequency ablation for intrahepatic cholangiocarcinoma

INTRODUCTION

The effectiveness of percutaneous radiofrequency ablation (RFA) in intrahepatic cholangiocarcinomas (iCCA) remains insufficiently studied.

METHODS

We conducted a retrospective study including patients with histologically proven iCCA within Milan criteria treated by percutaneous RFA from 2000 to 2022. The primary outcome was overall survival in treatment-naive patients and secondary outcomes included ablation completeness, adverse events, local and distant recurrence. A total of 494 patients with hepatocellular carcinoma (HCC) on cirrhosis treated by RFA were included as a comparison group. Oncological events were analysed using Kaplan-Meier, log-rank and univariate/multivariate Cox models.

RESULTS

The main population included 71 patients, mostly cirrhotic (80%) with solitary tumours (66%) of a median size of 24 mm. Local recurrence was 45% at 5 years, lower in multibipolar versus monopolar RFA (22% vs. 55%, p = .007). In treatment-naive patients (n = 45), median overall and recurrence-free survivals were 26 and 11 months, respectively. Tumour size (p = .01) and Child-Pugh B (p = .001) were associated with death. The rate of distant recurrence was 59% at 5 years significantly lower for single tumours of less than 2 (p = .002) or 3 cm (p = .02). In cirrhotic patients naïve of previous treatment (n = 40), overall survival was shorter than in HCC (26 vs 68 months, p < .0001), with more local recurrences (p < .0001). Among distant recurrences, 50% were extrahepatic metastases compared to 12% in HCC (p < .001).

CONCLUSION

Multibipolar RFA provides better results in terms of tumour recurrence than monopolar RFA and could be used to treat small iCCA (<3 cm). Adjuvant chemotherapy should be discussed due to the frequent extra-hepatic metastasis at recurrence.

mir-605-3p prevents liver premetastatic niche formation by inhibiting angiogenesis via decreasing exosomal nos3 release in gastric cancer

BACKGROUND

Cancer-induced pre-metastatic niches (PMNs) play a decisive role in promoting metastasis by facilitating angiogenesis in distant sites. Evidence accumulates suggesting that microRNAs (miRNAs) exert significant influence on angiogenesis during PMN formation, yet their specific roles and regulatory mechanisms in gastric cancer (GC) remain underexplored.

METHODS

miR-605-3p was identified through miRNA-seq and validated by qRT-PCR. Its correlation with the clinicopathological characteristics and prognosis was analyzed in GC. Functional assays were performed to examine angiogenesis both in vitro and in vivo. The related molecular mechanisms were elucidated using RNA-seq, immunofluorescence, transmission electron microscopy, nanoparticle tracking analysis, enzyme-linked immunosorbent assay, luciferase reporter assays and bioinformatics analysis.

RESULTS

miR-605-3p was screened as a candidate miRNA that may regulate angiogenesis in GC. Low expression of miR-605-3p is associated with shorter overall survival and disease-free survival in GC. miR-605-3p-mediated GC-secreted exosomes regulate angiogenesis by regulating exosomal nitric oxide synthase 3 (NOS3) derived from GC cells. Mechanistically, miR-605-3p reduced the secretion of exosomes by inhibiting vesicle-associated membrane protein 3 (VAMP3) expression and affects the transport of multivesicular bodies to the GC cell membrane. At the same time, miR-605-3p reduces NOS3 levels in exosomes by inhibiting the expression of intracellular NOS3. Upon uptake of GC cell-derived exosomal NOS3, human umbilical vein endothelial cells exhibited increased nitric oxide levels, which induced angiogenesis, established liver PMN and ultimately promoted the occurrence of liver metastasis. Furthermore, a high level of plasma exosomal NOS3 was clinically associated with metastasis in GC patients.

CONCLUSIONS

miR-605-3p may play a pivotal role in regulating VAMP3-mediated secretion of exosomal NOS3, thereby affecting the formation of GC PMN and thus inhibiting GC metastasis.

Clinical outcomes of immune checkpoint inhibitor combined with other targeted or immunological therapy regimens for the treatment of advanced bile tract cancer: a systematic review and meta-analysis

Background and aims

A single immune checkpoint inhibitor (ICI) regimen has limited value in treating advanced bile tract cancer (BTC); therefore, ICI combination therapy is often applied. This meta-analysis aimed to evaluate the effectiveness and safety of ICI combination therapy for advanced BTC.

Methods

The study protocol was registered on PROSPERO (CRD42023452422). Data on the median progression-free survival (PFS), median overall survival (OS), objective response rate (ORR), disease control rate (DCR), and grade ≥3 adverse events (AEs) reported in relevant studies were pooled and analyzed to determine the efficacy and safety of ICI combination therapy.

Results

In total, 15 studies with 665 patients were included in this meta-analysis. The overall ORR and DCR were 34.6% and 77.6%, respectively. The overall median PFS and OS were 6.06 months [95% confidence interval (CI): 4.91-7.21] and 12.11 months (95% CI: 10.66-13.55), respectively. Patients receiving ICI combination therapy in addition to other therapies had a considerably prolonged median PFS and OS (z=9.69, p<0.001 and z=16.17, p<0.001). Patients treated as first-line treatment had a substantially longer median PFS and OS compared to patients treated as non-first-line treatment (z=11.19, p<0.001 and z=49.17, p<0.001). The overall pooled grade ≥3 AEs rate was 38.2% (95% CI: 0.268-0.497) and was not influenced by whether ICI therapy was combined with other treatments or not or the treatment line.

Conclusion

Advanced BTC patients may benefit from ICI combination treatment without additional AEs. However, concurrent chemotherapy or radiotherapy is still needed to achieve better outcomes.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023452422.

Integrative multiomics enhancer activity profiling identifies therapeutic vulnerabilities in cholangiocarcinoma of different etiologies

OBJECTIVES

Cholangiocarcinoma (CCA) is a heterogeneous malignancy with high mortality and dismal prognosis, and an urgent clinical need for new therapies. Knowledge of the CCA epigenome is largely limited to aberrant DNA methylation. Dysregulation of enhancer activities has been identified to affect carcinogenesis and leveraged for new therapies but is uninvestigated in CCA. Our aim is to identify potential therapeutic targets in different subtypes of CCA through enhancer profiling.

DESIGN

Integrative multiomics enhancer activity profiling of diverse CCA was performed. A panel of diverse CCA cell lines, patient-derived and cell line-derived xenografts were used to study identified enriched pathways and vulnerabilities. NanoString, multiplex immunohistochemistry staining and single-cell spatial transcriptomics were used to explore the immunogenicity of diverse CCA.

RESULTS

We identified three distinct groups, associated with different etiologies and unique pathways. Drug inhibitors of identified pathways reduced tumour growth in in vitro and in vivo models. The first group (ESTRO), with mostly fluke-positive CCAs, displayed activation in estrogen signalling and were sensitive to MTOR inhibitors. Another group (OXPHO), with mostly BAP1 and IDH-mutant CCAs, displayed activated oxidative phosphorylation pathways, and were sensitive to oxidative phosphorylation inhibitors. Immune-related pathways were activated in the final group (IMMUN), made up of an immunogenic CCA subtype and CCA with aristolochic acid (AA) mutational signatures. Intratumour differences in AA mutation load were correlated to intratumour variation of different immune cell populations.

CONCLUSION

Our study elucidates the mechanisms underlying enhancer dysregulation and deepens understanding of different tumourigenesis processes in distinct CCA subtypes, with potential significant therapeutics and clinical benefits.

Prognosis of patients with advanced bile tract carcinoma: assessment using the modified-Gustave Roussy Immune Score (mGRIm-s) as a clinico-immunological tool

BACKGROUND

The emergence of immune checkpoint inhibitors (ICIs) has enhanced survival outcomes for certain patients with advanced biliary tract carcinoma (BTC). Pinpointing those who would benefit most from immunotherapy remains elusive. We investigated the predictive value of the modified Gustave Roussy Immune Score (mGRIm-s) in BTC patients treated with ICIs.

METHODS

Data from 110 patients at Chinese People's Liberation Army General Hospital, spanning September 2015 to April 2021, were analyzed. The median follow-up duration was 38.7 months as of December 2023. Risk factors included low albumin, high lactate dehydrogenase, and an elevated neutrophil-lymphocyte ratio. Patients were stratified into low (patients with no risk factors) and high (patients with at least one risk factor) mGRIm-s groups based on these factors.

RESULTS

Survival outcomes post-immunotherapy favored the low mGRIm-s group, with significantly improved progression-free survival (PFS) and overall survival (OS) (8.50 months vs. 3.70 months and 21.60 months vs. 8.00 months). COX regression confirmed an elevated risk in the high mGRIm-s group. Subgroup analysis highlighted a notable survival advantage for low mGRIm-s patients receiving first-line immunotherapy.

CONCLUSIONS

This study underscores mGRIm-s's potential in predicting immunotherapy response in BTC, paving the way for more targeted approaches.

Efficacy of dual checkpoint inhibitors in a patient with a mixed hepatocellular cholangiocarcinoma

A woman in her 60s was diagnosed with a metastatic, unresectable rare histological type of liver cancer; combined hepatocellular cholangiocarcinoma. She had palliative chemotherapy, initially with gemcitabine and cisplatin, and then with oxaliplatin, L-folinic acid and fluorouracil. Both treatment strategies demonstrated disease progression, and somatic mutation profiling revealed no actionable mutations. The patient was started on immuno-oncology (IO) with nivolumab and ipilimumab, followed by maintenance nivolumab. She has achieved a sustained ongoing partial response since the start of this therapy for at least 12 months. The outcome in this patient is in keeping with the growing evidence of the role that IO agents have in metastatic biliary tract cancer and also serves to highlight their importance in mixed histology liver tumours.

Clinicopathological features of cholangiolocarcinoma and impact of tumor heterogeneity on prognosis: A single institution retrospective study

Cholangiolocarcinoma (CLC) is an extremely rare tumor classified as a subtype of small duct-type intrahepatic cholangiocarcinoma (iCCA). There are few detailed reports on CLC and the prognostic impact of tumor heterogeneity is not clear. Between April 2006 and June 2022, of the 774 primary liver cancer resection cases who presented at Kanazawa University Hospital, 14 patients were pathologically diagnosed with CLC through immunohistochemical analysis of their molecular and biological features. Clinicopathological features and prognoses were evaluated retrospectively. Additionally, tumor heterogeneity was assessed and tumors were classified into pure and partial types according to the CLC component proportion in a single tumor. Chronic liver disease was observed in nine patients (64.3%). All tumors were mass-forming, and pathological R0 resection was achieved in 11 patients (78.6%). Tumor heterogeneity was classified as pure in 11 (78.6%) and partial in three (21.4%) patients. The median follow-up was 59.5 months (12-114 months). There was no difference in the 5-year disease-specific survival rates between the pure and partial (90.0% vs. 100.0%; P=0.200) types, but rates were significantly higher in the R0 resection group compared with those in the R1 resection group (100.0% vs. 50.0%; P=0.025). In conclusion, these results suggest that it is important for CLC patients to achieve curative resection, and CLC may have a good prognosis regardless of the proportion of CLC components in a single tumor.

Transcription factor EHF drives cholangiocarcinoma development through transcriptional activation of glioma-associated oncogene homolog 1 and chemokine CCL2

Cholangiocarcinoma (CCA) is characterized by rapid onset and high chance of metastasis. Therefore, identification of novel therapeutic targets is imperative. E26 transformation-specific homologous factor (EHF), a member of the E26 transformation-specific transcription factor family, plays a pivotal role in epithelial cell differentiation and cancer progression. However, its precise role in CCA remains unclear. In this study, through in vitro and in vivo experiments, we demonstrated that EHF plays a profound role in promoting CCA by transcriptional activation of glioma-associated oncogene homolog 1 (GLI1). Moreover, EHF significantly recruited and activated tumor-associated macrophages (TAMs) through the C-C motif chemokine 2/C-C chemokine receptor type 2 (CCL2/CCR2) axis, thereby remodeling the tumor microenvironment. In human CCA tissues, EHF expression was positively correlated with GLI1 and CCL2 expression, and patients with co-expression of EHF/GLI1 or EHF/CCL2 had the most adverse prognosis. Furthermore, the combination of the GLI1 inhibitor, GANT58, and CCR2 inhibitor, INCB3344, substantially reduced the occurrence of EHF-mediated CCA. In summary, our findings suggest that EHF is a potential prognostic biomarker for patients with CCA, while also advocating the therapeutic approach of combined targeting of GLI1 and CCL2/CCR2-TAMs to inhibit EHF-driven CCA development.

Clinical significance of small extracellular vesicles in cholangiocarcinoma

Cholangiocarcinoma is an aggressive and heterogeneous malignancy originating from the bile duct epithelium. It is associated with poor prognosis and high mortality. The global incidence of cholangiocarcinoma is rising, and there is an urgent need for effective early diagnosis and treatment strategies to reduce the burden of this devastating tumor. Small extracellular vesicles, including exosomes and microparticles, are nanoscale vesicles formed by membranes that are released both normally and pathologically from cells, mediating the intercellular transfer of substances and information. Recent studies have demonstrated the involvement of small extracellular vesicles in numerous biological processes, as well as the proliferation, invasion, and metastasis of tumor cells. The present review summarizes the tumorigenic roles of small extracellular vesicles in the cholangiocarcinoma microenvironment. Owing to their unique composition, accessibility, and stability in biological fluids, small extracellular vesicles have emerged as ideal biomarkers for use in liquid biopsies for diagnosing and outcome prediction of cholangiocarcinoma. Specific tissue tropism, theoretical biocompatibility, low clearance, and strong biological barrier penetration of small extracellular vesicles make them suitable drug carriers for cancer therapy. Furthermore, the potential value of small extracellular vesicle-based therapies for cholangiocarcinoma is also reviewed.

Treatment resistance in pancreatic and biliary tract cancer: molecular and clinical pharmacology perspectives

INTRODUCTION

Treatment resistance poses a significant obstacle in oncology, especially in biliary tract cancer (BTC) and pancreatic cancer (PC). Current therapeutic options include chemotherapy, targeted therapy, and immunotherapy. Resistance to these treatments may arise due to diverse molecular mechanisms, such as genetic and epigenetic modifications, altered drug metabolism and efflux, and changes in the tumor microenvironment. Identifying and overcoming these mechanisms is a major focus of research: strategies being explored include combination therapies, modulation of the tumor microenvironment, and personalized approaches.

AREAS COVERED

We provide a current overview and discussion of the most relevant mechanisms of resistance to chemotherapy, target therapy, and immunotherapy in both BTC and PC. Furthermore, we compare the different strategies that are being implemented to overcome these obstacles.

EXPERT OPINION

So far there is no unified theory on drug resistance and progress is limited. To overcome this issue, individualized patient approaches, possibly through liquid biopsies or single-cell transcriptome studies, are suggested, along with the potential use of artificial intelligence, to guide effective treatment strategies. Furthermore, we provide insights into what we consider the most promising areas of research, and we speculate on the future of managing treatment resistance to improve patient outcomes.

Heterogeneity, crosstalk, and targeting of cancer-associated fibroblasts in cholangiocarcinoma

Cholangiocarcinoma (CCA) comprises diverse tumors of the biliary tree and is characterized by late diagnosis, short-term survival, and chemoresistance. CCAs are mainly classified according to their anatomical location and include diverse molecular subclasses harboring inter-tumoral and intratumoral heterogeneity. Besides the tumor cell component, CCA is also characterized by a complex and dynamic tumor microenvironment where tumor cells and stromal cells crosstalk in an intricate network of interactions. Cancer-associated fibroblasts, one of the most abundant cell types in the tumor stroma of CCA, are actively involved in cholangiocarcinogenesis by participating in multiple aspects of the disease including extracellular matrix remodeling, immunomodulation, neo-angiogenesis, and metastasis. Despite their overall tumor-promoting role, recent evidence indicates the presence of transcriptional and functional heterogeneous CAF subtypes with tumor-promoting and tumor-restricting properties. To elucidate the complexity and potentials of cancer-associated fibroblasts as therapeutic targets in CCA, this review will discuss the origin of cancer-associated fibroblasts, their heterogeneity, crosstalk, and role during tumorigenesis, providing an overall picture of the present and future perspectives toward cancer-associated fibroblasts targeting CCA.

Isolation and characterization of small extracellular vesicles from murine primary mammary tumor

Tumor-derived small extracellular vesicles (TEVs) play a pivotal role in cancer progression by transferring functional biomolecules between the parental and recipient cells. Here, we present a protocol to isolate TEVs directly from murine primary mammary tumor using differential centrifugation. We describe steps for tissue dissociation, enzymatic digestion, and centrifugation. We then detail procedures for characterization of TEVs through transmission electron microscopy, immunoblotting, and nano-flow cytometry. This protocol can be used to extract EVs from other solid tumor types. For complete details on the use and execution of this protocol, please refer to Li, Mei-Xin et al. (2023).1.