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.

Long-term outcome following liver transplantation of patients with ACLF grade 3.

BACKGROUND AND AIMS: Utility, a major principle for allocation in the context of transplantation, is questioned in patients with acute-on chronic liver failure grade 3 (ACLF-3) who undergo liver transplantation (LT). We aimed to explore long-term outcomes of patients included the three-center retrospective French experience published in 2017. METHOD: All patients with ACLF-3 (n=73) as well as their transplanted matched controlled with ACLF-2 (n=145), 1 (n=119) and no ACLF (n=292) that have participated in the princeps study published in 2017 were included. We explored 5- and 10-year patient and graft survivals, causes of death and their predictive factors. RESULTS: Median follow-up of patients ACLF-3 patients was 7.5 years. At LT, median MELD was 40. In patients with ACLF-3, 2, 1 and no ACLF, 5-year patients' survivals were respectively 72.6% vs. 69.7% vs. 76.4% vs. 77.0% (p=0.31). Ten-year patients' survival ACLF-3 was 56.8% and was not different other groups (p=0.37) Leading causes of death in ACLF-3 patients were infections (33.3%), and cardiovascular events (23.3%). After exclusion of early death, UCLA futility risk score, age-adjusted Charlson comorbidity index and Chronic Liver Failure Consortium ACLF score were independently associated with 10-year patients' survival. Long-term grafts' survivals were not different across the groups. Clinical frailty scale and WHO performance status improved over time in patients alive after 5 years. CONCLUSION: 5- and 10-year patients' and grafts' survivals in ACLF-3 patients were not different from their controls. 5-year patients' survival is higher than that of the 50%-70% threshold defining the utility of liver graft. Efforts should focus on candidates' selection based on comorbidities as well as the prevention of infection and cardiovascular events standing as the main cause of death. IMPACT AND IMPLICATIONS: While short-term outcomes following liver transplantation in the most severely ill cirrhotic patients (ACLF-3) are known, long-term data are limited, raising questions about the utility of graft allocation in the context of scarce medical resources. This study provides a favorable long-term update, confirming no differences in 5- and 10-year patient and graft survival following liver transplantation in ACLF-3 patients compared to matched ACLF-2, ACLF-1, and no-ACLF patients. The study highlights the risk of dying from infection and cardiovascular causes in the long-term and identifies scores including comorbidities evaluation, such as the age-adjusted Charlson Comorbidity Index, as independently associated with long-term survival. Therefore, physicians should consider the cumulative burden of comorbidities when deciding to transplant these patients. Additionally, after transplantation, the study encourages mitigating infectious risk with tailored immunosuppressive regimens and managing tightly cardiovascular risk over time.

Clinical Application of Infrared Spectroscopy in Liver Transplantation for Rapid Assessment of Lipid Content in Liver Graft.

Liver transplantation (LT) is a major treatment for patients with end-stage liver diseases. Steatosis is a significant risk factor for primary graft nonfunction and associated with poor long-term graft outcomes. Traditionally, the evaluation of steatosis is based on frozen section examination to estimate the percentage of hepatocytes containing lipid vesicles. However, this visual evaluation correlates poorly with the true lipid content. This study aimed to address the potential of infrared (IR) microspectroscopy for rapidly estimating lipid content in the context of LT and assessing its impact on survival. Clinical data were collected for >20 months from 58 patients who underwent transplantation. For each liver graft, macrovacuolar steatosis and microvesicular steatosis were evaluated through histologic examination of frozen tissue section. Triglycerides (TG) were further quantified using gas phase chromatography coupled with a flame ionization detector (GC-FID) and estimated by IR microspectroscopy. A linear relationship and significant correlation were observed between the TG measured by GC-FID and those estimated using IR microspectroscopy (R2 = 0.86). In some cases, microvesicular steatosis was related to high lipid content despite low levels of macrovacuolar steatosis. Seven patients experienced posttransplantation liver failure, including 5 deceased patients. All patients underwent transplantation with grafts containing significantly high TG levels. A concentration of 250 nmol/mg was identified as the threshold above which the risk of failure after LT significantly increased, affecting 35% of patients. Our study established a strong correlation between LT outcomes and lipid content. IR microspectroscopy proved to be a rapid and reliable approach for assessing the lipid content in clinical settings.

Identification of liver transplant biopsy phenotypes associated with distinct liver biological markers and allograft survival.

The intricate association between histologic lesions and circulating antihuman leucocyte antigen donor-specific antibodies (DSA) in liver transplantation (LT) requires further clarification. We conducted a probabilistic, unsupervised approach in a comprehensively well-annotated LT cohort to identify clinically relevant archetypes. We evaluated 490 pairs of LT biopsies with DSA testing from 325 recipients transplanted between 2010 and 2020 across 3 French centers and an external cohort of 202 biopsies from 128 recipients. Unsupervised archetypal analysis integrated all clinico-immuno-histologic parameters of each biopsy to identify biopsy archetypes. The median time after LT was 1.17 (interquartile range, 0.38-2.38) years. We identified 7 archetypes distinguished by clinico-immuno-histologic parameters: archetype #1: severe T cell-mediated rejection (15.9%); #2: chronic rejection with ductopenia (1.8%); #3: architectural and microvascular damages (3.5%); #4: (sub)normal (55.9%); #5: mild T cell-mediated rejection (4.9%); #6: acute antibody-mediated rejection (6.5%); and #7: chronic rejection with DSA (11.4%). Cell infiltrates vary in the archetype. These archetypes were associated with distinct liver biological markers and allograft outcomes. These findings remained consistent when stratified using the patient's age or indications for LT, with good performance in the external cohort (mean highest probability assignment = 0.58, standard deviation ± 0.17). In conclusion, we have identified clinically meaningful archetypes, providing valuable insights into the intricate DSA-histology association, which may help standardize liver allograft pathology classification.

Liver transplant selection criteria and outcomes in critically ill patients with ACLF.

Background & Aims: Retrospective studies have reported good results with liver transplantation (LTx) for acute-on-chronic liver failure (ACLF) in selected patients. The aim of this study was to evaluate the selection process for LTx in patients with ACLF admitted to the intensive care unit (ICU) and to assess outcomes. Methods: This prospective, non-interventional, single high-volume center study collected data on patients with ACLF admitted to the ICU between 2017-2020. Results: Among 200 patients (mean age: 55.0 ± 11.2 years and 74% male), 96 patients (48%) were considered potential candidates for LTx. Unfavourable addictology criteria (n = 76) was the main reason for LTx ineligibility. Overall, 69 patients were listed for LTx (34.5%) and 50 were transplanted (25% of the whole population). The 1-year survival in the LTx group was significantly higher than in the non-transplanted group (94% vs. 15%, p <0.0001). Among patients eligible for LTx, mechanical ventilation during the first 7 days of ICU stay and an increase in the number of organ failures at day 3 were associated with the absence of LTx or death (odds ratio 9.58; 95% CI 3.29-27.89; p <0.0001 for mechanical ventilation and odds ratio 1.87; 95% CI 1.08-3.24; p <0.027 for increasing organ failures). The probability of not being transplanted in patients with ACLF under mechanical ventilation is >85.4% in those experiencing an increase of 2 organ failures since admission or >91% if experiencing an increase >2 organ failures, at which point futility could be considered. Conclusion: This prospective analysis of outcomes of patients with ACLF admitted to the ICU highlights the drastic nature of selection in this setting. Unfavourable addictology criteria, mechanical ventilation and increasing number of organ failures since admission were predictive of absence of LTx, futility and death. Impact and implications: Liver transplantation (LT) is the best therapeutic option in selected cirrhotic patients admitted to the ICU with acute on chronic liver failure. However, the selection criteria are poorly described and based on retrospective studies. This is the first prospective study that aimed to describe the selection process for LT in a transplant center. Patients with ACLF should be admitted to the ICU and evaluated within a short period of time for LT. In the context of organ shortage, eligibility for LT and either absence of LT, futility of care or death are better clarified in our study. These are mainly determined by prolonged respiratory failure and worsening of organ failures since ICU admission. Considering worldwide variations in the etiology and definition of ACLF, transplant availability and a narrow therapeutic window for transplant further prospective studies are awaited.

Early Deregulation of Cholangiocyte NR0B2 During Primary Sclerosing Cholangitis.

Background and Aims: Primary sclerosing cholangitis (PSC) is a probable autoimmune liver disease characterized by persistent and progressive biliary inflammation that leads to biliary infection, cirrhosis, or cholangiocarcinoma. Genome-wide omics data are scarce regarding this severe disease. Methods: MEDLINE database gene prioritization by text mining (biliary inflammation, biliary fibrosis, biliary stasis) was integrated in distinct omics data: (1) PSC liver transcriptome training and validation cohorts, (2) farnesoid X receptor (FXR) mice liver transcriptome subjected to an FXR agonist or FXR knockout mice; (3) liver single-cell transcriptome of the Abcb4-/- mice model of PSC. Results: A liver molecular network highlighted the involvement of nuclear receptor subfamily 0 group B member 2 (NR0B2) and its associated nuclear receptor FXR in a metabolic cascade that may influence the immune response. NR0B2 upregulation in PSC liver was independent of gender, age, body mass index, liver fibrosis, and PSC complications. Heterogeneity of NR0B2 upregulation was found in cholangiocyte cell types in which the NR0B2-based cell fate decision revealed the involvement of several metabolic pathways for detoxification (sulfur, glutathione derivative, and monocarboxylic acid metabolisms). Genes potentially implicated in carcinogenesis were also discovered on this cholangiocyte trajectory: GSTA3, inhibitor of DNA binding 2, and above all, TMEM45A, a transmembrane molecule from the Golgi apparatus considered as oncogenic in several cancers. Conclusion: By revisiting PSC through PubMed data mining, we evidenced the early cholangiocyte deregulation of NR0B2, highlighting a metabolic and premalignant reprogramming of the cholangiocyte cell type. The therapeutic targeting of NR0B2 could potentiate that of FXR and enable action on early events of the disease and prevent its progression.

External Validation of LCR1-LCR2, a Multivariable Hepatocellular Carcinoma Risk Calculator, in a Multiethnic Cohort of Patients With Chronic Hepatitis B.

Background and Aims: The liver cancer risk test (LCR1-LCR2) is a multianalyte blood test combining proteins involved in liver cell repair (apolipoprotein A1, haptoglobin), hepatocellular carcinoma (HCC) risk factors (gender, age, gamma glutamyl transpeptidase), a marker of fibrosis (alpha2-macroglobulin), and alpha-fetoprotein, a specific marker of HCC. The aim was to externally validate LCR1-LCR2 in hepatitis B. Methods: Preincluded patients were from the Hepather cohort, a multicenter, multiethnic prospective study in 6071 patients. The coprimary study outcome was the negative predictive value of LCR1-LCR2 at 5 years for the occurrence of HCC and survival without HCC according to the predetermined LCR1-LCR2 cutoffs, adjusted for risk covariables and for chronic hepatitis B treatment and quantified using time-dependent Cox proportional hazards models. A post hoc analysis compared the number of patients needed to screen one cancer by LCR1-LCR2 and PAGE-B. Results: A total of 3520 patients, 191 (5.4%) with cirrhosis, with at least 1 year of follow-up were included. A total of 76 HCCs occurred over a median (interquartile range) of 6.0 years (4.8-7.3) of follow-up. Among the 3367 patients with low-risk LCR1-LCR2, the 5-year negative predictive value was 99.3% (95% confidence interval = 99.0-99.6), with a significant Cox hazard ratio (6.4, 3.1-13.0; P < .001) obtained after adjustment for exposure to antivirals, age, gender, geographical origin, HBe-Ag status, alcohol consumption, and type-2 diabetes. LCR1-LCR2 outperformed PAGE-B for number of patients needed to screen mean (95% CI), 8.5 (3.2-8.1) vs 26.3 (17.5-38.5; P < .0001), respectively. Conclusion: The performance of LCR1-LCR2 to identify patients with chronic hepatitis B at very low risk of HCC at 5 years was externally validated. ClinicalTrials.gov: NCT01953458.