Mechanism-based target therapy in primary biliary cholangitis: opportunities before liver cirrhosis?

Risk stratification for patients with primary biliary cholangitis: early versus advanced-stage or non-cirrhosis versus cirrhosis?

BACKGROUND

Primary biliary cholangitis (PBC) is divided into early and advanced stages, which are two distinct disease states, and whether this division is optimal remains to be demonstrated.

AIMS

A risk stratification strategy was re-established according to histological stages and response criteria were defined accordingly.

METHODS

We retrospectively analyzed 721 patients with histological data. The endpoint events were liver-related death and liver transplantation (LT).

RESULTS

Histological stage IV was associated with LT-free survival compared to stage III (HR: 2.764, 95% CI: 1.457-5.247, p = 0.002); and stage III was not associated with LT-free survival compared to stage II (HR: 1.632, 95% CI: 0.833-3.195, p = 0.153). Total bilirubin was associated with LT-free survival (HR: 1.162, 95% CI: 1.079-1.251, p < 0.001), whereas alkaline phosphatase was not associated with LT-free survival in cirrhotic patients (HR: 1.256, 95% CI: 0.958-1.648, p = 0.100). Compared to Paris I, Paris II, and Toronto, Rotterdam had the highest area under the receiver operating characteristic curve (AUC) for predicting the 5-year endpoint events in cirrhotic patients (0.652 [0.558-0.745]). Patients who had poor response according to Rotterdam criteria had worse prognosis than those who were biochemical responders (p = 0.036). Compared to Paris II and Paris I (for stage III) + Paris II (for stage I-II), Paris I, Rotterdam, and Toronto had higher AUC in non-cirrhotic patients (p < 0.05).

CONCLUSIONS

Risk stratification based on histological classification of non-cirrhosis versus cirrhosis demonstrates superior clinical utility compared to the early versus advanced stage stratification. Furthermore, the Rotterdam criteria proved to be clinically applicable for assessing biochemical responses specifically in patients with histological cirrhosis.

Causal Association Between Circulating Inflammatory Proteins and Autoimmune Liver Disease: a Bidirectional Two-Sample Mendelian Randomization Study

Introduction

To investigate whether there is a direct causal relationship between circulating inflammatory proteins and autoimmune liver disease (AILD).

Materials and Methods

We collected genetic data for various AILD from the Genome Wide Association Studies (GWAS) dataset. The latest research provides GWAS data for 91 proteins associated with inflammation. Perform bidirectional two sample Mendelian randomization (MR) analysis using inverse variance weighted (IVW) to determine the causal relationship between inflammatory proteins and AILD, and use Mendelian randomization Egger method (MR Egger), weighted median (WM), and weighted mode as supplementary evaluations. In addition, we conducted sensitivity analysis.

Results

Positive MR analysis showed that CDCP1 (OR=1.363, p=0.0465) and IL-18 (OR=1.416, p=0.0477) were associated with higher including autoimmune hepatitis (AIH) risk. Higher CXCL11 (OR=1.574, p=9.23×10-5) were associated with an increased risk of primary biliary cholangitis (PBC). Lower levels of three inflammatory proteins were associated with increased risk of PBC. TNFSF12 (OR=1.827, p=0.0001, p_adj_fdr=0.0063), CD6 isoform (OR=1.126, p=0.0389), CCL20 (OR=1.880, p=0.0395) are associated with increased risk of primary sclerosing cholangitis (PSC). Reverse MR imaging showed that PBC may promote the expression levels of CCL4 (OR=1.023, p=0.0201) and OSM (OR=1.022, p=0.0236). PSC may promote the expression of five inflammatory proteins. Sensitivity analysis further excluded the effects of heterogeneity and horizontal pleiotropy.

Conclusion

This study indicates a potential association between circulating inflammatory proteins and AILD, which may become a new diagnostic indicator or drug target for clinical application in the prevention and treatment of AILD. However, further investigation is needed.

A Closer Look into Autoimmune Liver Diseases

Autoimmune liver diseases involve a heterogeneous group of chronic inflammatory disorders, including autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis. Sometimes presented consistently as an overlapping syndrome, their pathogenesis is rather complex and has yet to be fully elucidated, despite extensive research efforts. This review article corroborates the molecular mechanisms of autoimmune liver diseases, as well as existing and potential therapeutic modalities.

Breaking Grounds: A Comprehensive Analysis of Cutting-Edge Treatments for Primary Biliary Cirrhosis/Primary Biliary Cholangitis With Futuristic Treatments

Primary biliary cholangitis (PBC) is an autoimmune disorder characterized by biliary destruction leading to intrahepatic biliary cholestasis. It predominantly affects women during the fifth and sixth decades. Treatment options have progressed from ursodeoxycholic acid (UDCA) and obeticholic acid (OCA) to liver and stem cell transplant. The objectives include summarizing established and new diagnostic approaches for PBC along with reviewing efficacy treatments, their side effects, and future directions. The treatment of PBC is based on risk stratification, including assessment of the patient's age, sex, clinical pattern, biochemical and antibody profile, histology, and markers of fibrosis. UDCA and OCA are Food and Drug Administration (FDA) approved first-line and second-line agents. Elafibranor, a recently FDA-approved agent based on its efficacy, was shown in the ELATIVE trial. Seladelpar, currently under FDA review in the ENHANCE III trial, is also used in PBC. Fibrates, a third-line treatment, are found efficacious in different trials. Other treatment options are in phase II/III clinical trials. The question of whether we use immunotherapy has been answered in the NCT02376335 and NCT00746486 trials, stating that rituximab and budesonide cannot be used as no clinical significance is observed. The emergence of new therapies and the potential of combination treatments offer hope for improving outcomes for all patients with PBC. Personalized treatment strategies, continuous monitoring, and a comprehensive approach to symptom management are key to optimizing care and enhancing the quality of life for individuals affected by this chronic liver disease.

Current Treatment Regimens and Promising Molecular Therapies for Chronic Hepatobiliary Diseases

Chronic hepatobiliary damage progressively leads to fibrosis, which may evolve into cirrhosis and/or hepatocellular carcinoma. The fight against the increasing incidence of liver-related morbidity and mortality is challenged by a lack of clinically validated early-stage biomarkers and the limited availability of effective anti-fibrotic therapies. Current research is focused on uncovering the pathogenetic mechanisms that drive liver fibrosis. Drugs targeting molecular pathways involved in chronic hepatobiliary diseases, such as inflammation, hepatic stellate cell activation and proliferation, and extracellular matrix production, are being developed. Etiology-specific treatments, such as those for hepatitis B and C viruses, are already in clinical use, and efforts to develop new, targeted therapies for other chronic hepatobiliary diseases are ongoing. In this review, we highlight the major molecular changes occurring in patients affected by metabolic dysfunction-associated steatotic liver disease, viral hepatitis (Delta virus), and autoimmune chronic liver diseases (autoimmune hepatitis, primary biliary cholangitis, and primary sclerosing cholangitis). Further, we describe how this knowledge is linked to current molecular therapies as well as ongoing preclinical and clinical research on novel targeting strategies, including nucleic acid-, mesenchymal stromal/stem cell-, and extracellular vesicle-based options. Much clinical development is obviously still missing, but the plethora of promising potential treatment strategies in chronic hepatobiliary diseases holds promise for a future reversal of the current increase in morbidity and mortality in this group of patients.

Sinusoidal communication in chronic liver disease

The liver sinusoid, mainly composed of liver sinusoidal endothelial cells, hepatic macrophages and hepatic stellate cells, shapes the hepatic vasculature and is key to maintaining liver homeostasis and function. During chronic liver disease (CLD), the function of sinusoidal cells is impaired, being directly involved in the progression of liver fibrosis, cirrhosis, and main clinical complications including portal hypertension and hepatocellular carcinoma. In addition to their roles in liver diseases pathobiology, sinusoidal cells' paracrine communication or cross-talk is being studied as a mechanism of disease but also as a remarkable target for treatment. The aim of this review is to gather current knowledge of intercellular signalling in the hepatic sinusoid during the progression of liver disease. We summarise studies developed in pre-clinical models of CLD, especially emphasizing those pathways characterized in human-based clinically relevant models. Finally, we describe pharmacological treatments targeting sinusoidal communication as promising options to treat CLD and its clinical complications.

A Comparative Analysis of ADRs under Obeticholic Acid and Ursodeoxycholic Acid in Cholestatic Liver Diseases Using the FAERS Database

BACKGROUND

The objective of this study was to compare the safety profiles of OCA and UDCA for the treatment of PBC using the FDA Adverse Event Reporting System database.

METHODS

We extracted reports for OCA from 2016 to 2023 and UDCA from 2004 to 2023. Demographic details, adverse events (AEs), and concomitant medications were analyzed using descriptive statistics and signal detection methods.

RESULTS

The most common for OCA were pruritus (1345 cases, ROR 20.96) and fatigue (528 cases, ROR 3.46). UDCA was more frequently associated with hepatocellular carcinoma (22 cases, ROR 16.37) and type I hypersensitivity reactions (11 cases, ROR 12.77). OCA was also linked to a higher frequency of constipation (161 cases, ROR 3.92) and increased blood alkaline phosphatase levels (145 cases, ROR 44.27).

CONCLUSION

This study reveals distinct safety profiles for OCA and UDCA in the treatment of PBC. OCA is associated with a higher frequency of pruritus, fatigue, constipation, and increased blood alkaline phosphatase levels, while UDCA is linked to hepatocellular carcinoma and type I hypersensitivity reactions. These findings support personalized treatment approaches based on individual patient characteristics.

Determining the association between systematic lupus erythematosus and the occurrence of primary biliary cirrhosis: a systematic review and meta-analysis

BACKGROUND

Autoimmune diseases often coexist; however, the concomitant occurrence of systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) is rare. Therefore, this study aims to provide a comprehensive summary of evidence regarding the co-occurrence of SLE and PBC.

METHODS

PubMed, Web of Science, ScienceDirect , and Google Scholar databases were systematically and comprehensively searched for records published up to February 2024. Full-text articles that aligned with the study's aim were included, while those published in languages other than English and those designed as case reports, reviews, conference abstracts, or editorials were excluded. Statistical analyses were performed using Comprehensive Meta-Analysis software, and methodological quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

Only 14 studies that met the inclusion criteria with 3944 PBC and 9414 SLE patients were included for review and analysis. Pooled data analysis revealed that approximately 1.1% of SLE patients have concomitant PBC (range: 0.02-7.5%), while around 2.7% of PBC patients concurrently have SLE (range: 1.3-7.5%). Furthermore, qualitative data analysis indicated that the prevalence of PBC in SLE patients presenting with hepatic dysfunction or abnormal liver enzymes ranges from 2 to 7.5%.

CONCLUSION

Although the concomitant occurrence of SLE and PBC is rare, the small proportion of patients where these diseases coexist warrants close monitoring by clinicians. This underscores the importance of surveillance to prevent their co-occurrence.

Current Perspectives on the Molecular and Clinical Relationships between Primary Biliary Cholangitis and Hepatocellular Carcinoma

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterised by the immune-mediated destruction of small and medium intrahepatic bile ducts, with variable outcomes and progression. This review summarises the state of the art regarding the risk of neoplastic progression in PBC patients, with a particular focus on the molecular alterations present in PBC and in hepatocellular carcinoma (HCC), which is the most frequent liver cancer in these patients. Major risk factors are male gender, viral infections, e.g., HBV and HCV, non-response to UDCA, and high alcohol intake, as well as some metabolic-associated factors. Overall, HCC development is significantly more frequent in patients with advanced histological stages, being related to liver cirrhosis. It seems to be of fundamental importance to unravel eventual dysfunctional molecular pathways in PBC patients that may be used as biomarkers for HCC development. In the near future, this will possibly take advantage of artificial intelligence-designed algorithms.

Causal relationship between systemic lupus erythematosus and primary liver cirrhosis based on two-sample bidirectional Mendelian randomization and transcriptome overlap analysis

BACKGROUND

Overlapping cases of systemic lupus erythematosus (SLE) and primary biliary cirrhosis (PBC) are rare and have not yet been fully proven to be accidental or have a common genetic basis.

METHODS

Two-sample bidirectional Mendelian randomization (MR) analysis was applied to explore the potential causal relationship between SLE and PBC. The heterogeneity and reliability of MR analysis were evaluated through Cochran's Q-test and sensitivity test, respectively. Next, transcriptome overlap analysis of SLE and PBC was performed using the Gene Expression Omnibus database to identify the potential mechanism of hub genes. Finally, based on MR analysis, the potential causal relationship between hub genes and SLE or PBC was validated again.

RESULTS

The MR analysis results indicated that SLE and PBC were both high-risk factors for the occurrence and development of the other party. On the one hand, MR analysis had heterogeneity, and on the other hand, it also had robustness. Nine hub genes were identified through transcriptome overlap analysis, and machine learning algorithms were used to verify their high recognition efficiency for SLE patients. Finally, based on MR analysis, it was verified that there was no potential causal relationship between the central gene SOCS3 and SLE, but it was a high-risk factor for the potential risk of PBC.

CONCLUSION

The two-sample bidirectional MR analysis revealed that SLE and PBC were high-risk factors for each other, indicating that they had similar genetic bases, which could to some extent overcome the limitation of insufficient overlap in case samples of SLE and PBC. The analysis of transcriptome overlapping hub genes provided a theoretical basis for the potential mechanisms and therapeutic targets of SLE with PBC overlapping cases.

Diagnostic value of anti-mitochondrial antibody in patients with primary biliary cholangitis: A systemic review and meta-analysis

BACKGROUND

Anti-mitochondrial antibodies (AMA) and the M2 subtype are considered serological hallmarks in the diagnosis of primary biliary cholangitis (PBC). However, these autoantibodies may be undetectable in some patients. This meta-analysis aimed to evaluate the diagnostic accuracy of serum AMA and M2 for PBC.

METHODS

We systematically searched PubMed, Embase, Web of Science, and the Cochrane Library for relevant studies. Pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR) were calculated using a random-effects model. We also constructed hierarchical summary receiver operating characteristic curves and calculated the area under the curve values.

RESULTS

Our meta-analysis included 28 studies, of which 24 examined the diagnostic accuracy of AMA for PBC. Pooled sensitivity and specificity of AMA were 84% (95% confidence intervals [CI] 77-90%) and 98% (96-99%), respectively. Pooled LR+, LR-, and DOR were 42.2 (22.1-80.5), 0.16 (0.11-0.24), and 262 (114-601), respectively. Sixteen studies explored the diagnostic value of the M2 subtype, demonstrating pooled sensitivity and specificity of 89% (81-94%) and 96% (93-98%), respectively. Pooled LR+, LR-, and DOR were 20.3 (8.0-51.1), 0.12 (0.05-0.26), and 169 (41-706), respectively. The hierarchical summary receiver operating characteristic curves for both of serum AMA and M2 subtype lie closer to the upper left corner of the plot with area under the curve values of 0.98 (95% CI = 0.96-0.99) and 0.98 (95% CI = 0.96-0.99) respectively.

CONCLUSION

This meta-analysis provides evidence affirming the utility of AMA and M2 as sensitive and specific serological hallmarks that can facilitate early screening and diagnosis of PBC.