Deep Learning-Enabled Diagnosis of Liver Adenocarcinoma.

BACKGROUND & AIMS: Diagnosis of adenocarcinoma in the liver is a frequent scenario in routine pathology and has a critical impact on clinical decision making. However, rendering a correct diagnosis can be challenging, and often requires the integration of clinical, radiologic, and immunohistochemical information. We present a deep learning model (HEPNET) to distinguish intrahepatic cholangiocarcinoma from colorectal liver metastasis, as the most frequent primary and secondary forms of liver adenocarcinoma, with clinical grade accuracy using H&E-stained whole-slide images. METHODS: HEPNET was trained on 714,589 image tiles from 456 patients who were randomly selected in a stratified manner from a pool of 571 patients who underwent surgical resection or biopsy at Heidelberg University Hospital. Model performance was evaluated on a hold-out internal test set comprising 115 patients and externally validated on 159 patients recruited at Mainz University Hospital. RESULTS: On the hold-out internal test set, HEPNET achieved an area under the receiver operating characteristic curve of 0.994 (95% CI, 0.989-1.000) and an accuracy of 96.522% (95% CI, 94.521%-98.694%) at the patient level. Validation on the external test set yielded an area under the receiver operating characteristic curve of 0.997 (95% CI, 0.995-1.000), corresponding to an accuracy of 98.113% (95% CI, 96.907%-100.000%). HEPNET surpassed the performance of 6 pathology experts with different levels of experience in a reader study of 50 patients (P = .0005), boosted the performance of resident pathologists to the level of senior pathologists, and reduced potential downstream analyses. CONCLUSIONS: We provided a ready-to-use tool with clinical grade performance that may facilitate routine pathology by rendering a definitive diagnosis and guiding ancillary testing. The incorporation of HEPNET into pathology laboratories may optimize the diagnostic workflow, complemented by test-related labor and cost savings.

Comprehensive clinicopathologic study of alpha fetoprotein-expression in a large cohort of patients with hepatocellular carcinoma.

Alpha fetoprotein (AFP) is the most widely used diagnostic and prognostic serum biomarker for hepatocellular carcinoma (HCC). Despite its wide clinical use, a systematic clinicopathologic study comparing AFP expression in HCC in situ with serum AFP concentrations has not yet been conducted. To analyze AFP expression in a large cohort of patients by immunohistochemistry, we employed a comprehensive tissue microarray with 871 different HCCs of overall 561 patients. AFP immunoreactivity was detected in only about 20% of HCC core biopsies, whereas 48.9% of the patients displayed increased serum values (>12 ng/mL). Immunostaining of whole tumor slides revealed that lack of detectable immunoreactivity in core biopsies in a subgroup of patients with elevated AFP serum concentrations is due to heterogeneous intratumoral AFP expression. Serum AFP concentrations and AFP expression in situ were moderately correlated (Spearman's rank correlation coefficient .53, P = 1.2e - 13). High AFP expression detected in serum (>227.3 ng/mL) or in situ predicted unfavorable prognosis and was associated with vascular invasion, higher tumor grade and macrotrabecular-massive tumor subtype. Multivariate and ROC curve analysis demonstrated that high AFP concentrations in serum is an independent prognostic parameter and represents the more robust prognostic predictor in comparison to AFP immunostaining of core biopsies. The previously published vessels encapsulating tumor clusters (VETC) pattern turned out as an additional, statistically independent prognostic parameter. AFP-positivity was associated with increased tumor cell apoptosis, but not with increased vascular densities. Additionally, AFP-positive tumors displayed increased proliferation rates, urea cycle dysregulation and signs of genomic instability, which may constitute the basis for their increased aggressiveness.

Lipid Droplet-Associated Proteins Perilipin 1 and 2: Molecular Markers of Steatosis and Microvesicular Steatotic Foci in Chronic Hepatitis C.

Chronic infection with hepatitis C (HCV) is a major risk factor in the development of cirrhosis and hepatocellular carcinoma. Lipid metabolism plays a major role in the replication and deposition of HCV at lipid droplets (LDs). We have demonstrated the importance of LD-associated proteins of the perilipin family in steatotic liver diseases. Using a large collection of 231 human liver biopsies with HCV, perilipins 1 and 2 have been localized to LDs of hepatocytes that correlate with the degree of steatosis and specific HCV genotypes, but not significantly with the HCV viral load. Perilipin 1- and 2-positive microvesicular steatotic foci were observed in 36% of HCV liver biopsies, and also in chronic hepatitis B, autoimmune hepatitis and mildly steatotic or normal livers, but less or none were observed in normal livers of younger patients. Microvesicular steatotic foci did not frequently overlap with glycogenotic/clear cell foci as determined by PAS stain in serial sections. Steatotic foci were detected in all liver zones with slight architectural disarrays, as demonstrated by immunohistochemical glutamine synthetase staining of zone three, but without elevated Ki67-proliferation rates. In conclusion, microvesicular steatotic foci are frequently found in chronic viral hepatitis, but the clinical significance of these foci is so far not clear.

[Hepatocellular carcinoma in an inflammatory adenoma with ß-catenin mutation in a patient with hepatocellular adenomatosis due to germline mutation in HNF1α]. / Entstehung eines hepatozellulären Karzinoms in einem inflammatorischen Adenom mit ß-Catenin-Mutation bei einem Patienten mit hepatozellulärer Adenomatose und HNF1α-Keimbahnmutation.

Hepatocyte nuclear factor 1 α (HNF1α) mutations cause maturity-onset diabetes of the young (MODY) type 3 and are associated with hepatocellular adenomatosis. Malignant transformation of HNF1α-mutated hepatocellular adenomas is rare. We report a case of a 28-year-old man with HNF1α-inactivated adenomatosis who developed an inflammatory adenoma with ß catenin mutation with malignant transformation into a well-differentiated hepatocellular carcinoma (HCC).

Controlled attenuation parameter and alcoholic hepatic steatosis: Diagnostic accuracy and role of alcohol detoxification.

BACKGROUND & AIMS: Controlled attenuation parameter (CAP) is a novel non-invasive measure of hepatic steatosis, but it has not been evaluated in alcoholic liver disease. Therefore, we aimed to validate CAP for the assessment of biopsy-verified alcoholic steatosis and to study the effect of alcohol detoxification on CAP. METHODS: This was a cross-sectional biopsy-controlled diagnostic study in four European liver centres. Consecutive alcohol-overusing patients underwent concomitant CAP, regular ultrasound, and liver biopsy. In addition, we measured CAP before and after admission for detoxification in a separate single-centre cohort. RESULTS: A total of 562 patients were included in the study: 269 patients in the diagnostic cohort with steatosis scores S0, S1, S2, and S3 = 77 (28%), 94 (35%), 64 (24%), and 34 (13%), respectively. CAP diagnosed any steatosis and moderate steatosis with fair accuracy (area under the receiver operating characteristic curve [AUC] ≥S1 = 0.77; 0.71-0.83 and AUC ≥S2 = 0.78; 0.72-0.83), and severe steatosis with good accuracy (AUC S3 = 0.82; 0.75-0.88). CAP was superior to bright liver echo pattern by regular ultrasound. CAP above 290 dB/m ruled in any steatosis with 88% specificity and 92% positive predictive value, while CAP below 220 dB/m ruled out steatosis with 90% sensitivity, but 62% negative predictive value. In the 293 patients who were admitted 6.3 days (interquartile range 4-6) for detoxification, CAP decreased by 32 ±â€¯47 dB/m (p <0.001). Body mass index predicted higher CAP in both cohorts, irrespective of drinking pattern. Obese patients with body mass index ≥30 kg/m2 had a significantly higher CAP, which did not decrease significantly during detoxification. CONCLUSIONS: CAP has a good diagnostic accuracy for diagnosing severe alcoholic liver steatosis and can be used to rule in any steatosis. In non-obese but not in obese, patients, CAP rapidly declines after alcohol withdrawal. LAY SUMMARY: CAP is a new ultrasound-based technique for measuring fat content in the liver, but has never been tested for fatty liver caused by alcohol. Herein, we examined 562 patients in a multicentre setting. We show that CAP highly correlates with liver fat, and patients with a CAP value above 290 dB/m were highly likely to have more than 5% fat in their livers, determined by liver biopsy. CAP was also better than regular ultrasound for determining the severity of alcoholic fatty-liver disease. Finally, we show that three in four (non-obese) patients rapidly decrease in CAP after short-term alcohol withdrawal. In contrast, obese alcohol-overusing patients were more likely to have higher CAP values than lean patients, irrespective of drinking.

Widespread expression of perilipin 5 in normal human tissues and in diseases is restricted to distinct lipid droplet subpopulations.

Diseases associated with the accumulation of lipid droplets are increasing in western countries. Lipid droplet biogenesis, structure and degradation are regulated by proteins of the perilipin family. Perilipin 5 has been shown to regulate basal lipolysis in oxidative tissues. We examine perilipin 5 in normal human tissues and in diseases using protein biochemical and microscopic techniques. Perilipin 5 was constitutively located at small lipid droplets in skeletal myocytes, cardiomyocytes and brown adipocytes. In addition, perilipin 5 was detected in the epithelia of the gastrointestinal and urogenital tract, especially in hepatocytes, the mitochondria-rich parietal cells of the stomach, tubular kidney cells and ductal cells of the salivary gland and pancreas. Granular cytoplasmic expression, without a lipid droplet-bound localization was detected elsewhere. In cardiomyopathies, in skeletal muscle diseases and during hepatocyte steatogenesis, perilipin 5 was upregulated and localized to larger and more numerous lipid droplets. In steatotic human hepatocytes, perilipin 5 was moderately increased and colocalized with perilipins 1 and 2 but not with perilipin 3 at lipid droplets. In liver diseases implicated in alterations of mitochondria, such as mitochondriopathies, alcoholic liver disease, Wilson's disease and acute liver injury, perilipin 5 was frequently localized to small lipid droplets and less in the cytoplasm. In tumorigenesis, perilipin 5 was especially upregulated in lipo-, leio- and rhabdomyosarcoma and hepatocellular and renal cell carcinoma. In summary, our study provides evidence that perilipin 5 is not restricted to certain cell types but localizes to distinct lipid droplet subpopulations reflecting a possible function in oxidative energy supply in normal tissues and in diseases.

Sensitive and non-invasive assessment of hepatocellular iron using a novel room-temperature susceptometer.

BACKGROUND & AIMS: Liver iron accumulates in various chronic liver diseases where it is an independent factor for survival and carcinogenesis. We tested a novel room-temperature susceptometer (RTS) to non-invasively assess liver iron concentration (LIC). METHODS: Two hundred and sixty-four patients with or without signs of iron overload or liver disease were prospectively enrolled. Thirty-five patients underwent liver biopsy with semiquantitative iron determination (Prussian Blue staining), atomic absorption spectroscopy (AAS, n=33), or magnetic resonance imaging (MRI, n=15). RESULTS: In vitro studies demonstrated a highly linear (r2=0.998) association between RTS-signal and iron concentration, with a detection limit of 0.3mM. Using an optimized algorithm, accounting for the skin-to-liver capsule distance, valid measurements could be obtained in 84% of cases. LIC-RTS showed a significant correlation with LIC-AAS (r=0.74, p<0.001), LIC-MRI (r=0.64, p<0.001) and hepatocellular iron (r=0.58, p<0.01), but not with macrophage iron (r=0.32, p=0.30). Normal LIC-RTS was 1.4mg/g dry weight. Besides hereditary and transfusional iron overload, LIC-RTS was also significantly elevated in patients with alcoholic liver disease. The areas under the receiver operating characteristic curve (AUROC) for grade 1, 2 and 3 hepatocellular iron overload were 0.72, 0.89 and 0.97, respectively, with cut-off values of 2.0, 4.0 and 5.0mg/g dry weight. Notably, the positive and negative predictive values, sensitivity, specificity and accuracy of severe hepatic iron overload (HIO) (grade ≥2) detection, were equal to AAS and superior to all serum iron markers. Depletion of hepatic iron could be efficiently monitored upon phlebotomy. CONCLUSIONS: RTS allows for the rapid and non-invasive measurement of LIC. In comparison to MRI, it could be a cost-effective bedside method for LIC screening. Lay summary: Novel room-temperature susceptometer (RTS) allows for the rapid, sensitive, and non-invasive measurement of liver iron concentration. In comparison to MRI, it could be a cost-effective bedside method for liver iron concentration screening.

Perilipin discerns chronic from acute hepatocellular steatosis.

BACKGROUND & AIMS: Hepatocellular steatosis is the most frequent liver disease in the western world and may develop further to steatohepatitis, liver cirrhosis and hepatocellular carcinoma. We have previously shown that lipid droplet (LD)-associated proteins of the perilipin/PAT-family are differentially expressed in hepatocyte steatosis and that perilipin is expressed de novo. The aim of this study was to determine the conditions for the temporal regulation of de novo synthesis of perilipin in vitro and in vivo. METHODS: Immunohistochemical PAT-analysis was performed with over 120 liver biopsies of different etiology and duration of steatosis. Steatosis was induced in cultured hepatocytic cells with combinations of lipids, steatogenic substances and DMSO for up to 40 days under conditions of stable down-regulation of adipophilin and/or TIP47. RESULTS: Whereas perilipin and adipophilin were expressed in human chronic liver disease irrespective of the underlying etiology, in acute/microvesicular steatosis TIP47, and MLDP were recruited from the cytoplasm to LDs, adipophilin was strongly increased, but perilipin was virtually absent. In long-term steatosis models in vitro, TIP47, MLDP, adipophilin, and finally perilipin were gradually induced. Perilipin and associated formation of LDs were intricately regulated on the transcriptional (PPARs, C/EBPs, SREBP), post-transcriptional, and post-translational level (TAG-amount, LD-fusion, phosphorylation-dependent lipolysis). In long-term steatosis models under stable down-regulation of adipophilin and/or TIP47, MLDP substituted for TIP47, and perilipin for adipophilin. CONCLUSIONS: LD-maturation in hepatocytes in vivo and in vitro involves sequential expression of TIP47, MLDP, adipophilin and finally perilipin. Thus, perilipin might be used for the differential diagnosis of chronic vs. acute steatosis.

Combined Resection of Liver and Hilar Bifurcation for Colorectal Liver Metastasis: A Single-Center Experience and Review of the Literature.

Introduction: Colorectal liver metastases (CRLM) infiltrating the hilar bifurcation is rarely described. We investigated the outcome of partial hepatectomy combined with resection of the hilar bifurcation. Methods: Data collection for patients who underwent resection for CRLM at our institution was performed prospectively from January 2008 to August 2021. Follow-up ended in August 2023. Patients with and without bile duct infiltration of CRLM were analyzed retrospectively. The primary endpoints were overall (OS) and recurrence-free survival (RFS). Results: A total of 1,156 liver resections were screened. Out of those, 18 were combined resections of the liver and the hilar bifurcation. Bile duct infiltration of CRLM was histologically proven in 5 of 18 cases. Preoperative mild obstructive jaundice occurred in 6 of 18 patients and was treated by drainage. Out of those, only 2 had a confirmed infiltration of the hilar bifurcation by CRLM. The median recurrence-free survival (RFS) was 10 months in those patients with bile duct infiltration compared to 9 months in those with no infiltration (p = 0.503). Conclusion: While CRLM is common, infiltration into the central biliary tract is rare. Tumor invasion of the biliary tree can cause jaundice, but jaundice does not necessarily mean tumor invasion. We have shown that combined resection of the liver and hilar bifurcation for CRLM is safe and infiltration of the bile duct by CRLM did not seem to have a significant effect on RFS or OS.

Adipophilin/perilipin-2 as a lipid droplet-specific marker for metabolically active cells and diseases associated with metabolic dysregulation.

AIMS: Lipid droplets (LDs) are dynamic storage compartments for energy-rich fats that are nearly ubiquitously present in eukaryotic cells, exerting tissue-specific functions in metabolically active cell types, and are increased in conditions following cellular damage or lipid overload. The LD-cytoplasm interface is stabilized by amphiphilic proteins of the PAT/perilipin family (perilipin/perilipin-1, adipophilin/perilipin-2, and TIP47/perilipin-3). We evaluated the value of adipophilin immunohistochemistry for the diagnosis of diseases associated with LD accumulation. METHODS AND RESULTS: In human tissues, adipophilin-positive LDs were especially prominent in steroidogenic cells of the adrenal gland, testis, and ovary, in hepatocytes and hepatic stellate cells, in cardiac, striated and smooth myocytes, in lactating mammary gland epithelial cells, and in plurivacuolar adipocytes. Variable amounts of adipophilin-positive LDs were also detected almost ubiquitously in epithelial cells of the gastrointestinal tract and skin. In diseases associated with lipid storage, adipophilin was strongly expressed in lipid-laden macrophages in atherosclerosis, in cardiomyopathies, kidney diseases, hepatocyte steatosis, colon ischaemia, and at the border of organ infarcts. CONCLUSIONS: Adipophilin immunohistochemistry visualizes small LDs in tissues under physiological and disease conditions that are not visible by conventional light microscopy. Immunohistology for adipophilin may facilitate histomorphological diagnosis of diseases and definition of the extent of metabolic dysregulation, such as in organ infarcts, cardiomyopathies, kidney diseases, and microvesicular steatosis.

Reduced Lipid Peroxidation Predicts Unfavorable Prognosis in Hepatocellular Carcinoma, but Not Intrahepatic Cholangiocarcinoma.

Primary liver cancer, including hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA), remains a significant contributor to cancer-related mortality worldwide. Oxidative stress and lipid peroxidation play a key role in chronic liver diseases and have been shown to be pivotal for tumor initiation and progression. 4-hydroxy-nonenal (4-HNE), one of the major mediators of oxidative stress and a well-established biomarker for lipid peroxidation, can act as a signal transducer, inducing inflammation and exerting carcinogenic effects. However, the role of 4-HNE in primary liver cancer remains poorly explored. In this study, we investigated 4-HNE levels in 797 liver carcinomas, including 561 HCC and 236 iCCA, by immunohistochemistry. We then correlated 4-HNE levels with comprehensive clinical data and survival outcomes. In HCC, lower expression levels of 4-HNE were associated with vascular invasion, a high tumor grade, a macrotrabecular-massive HCC subtype, and poor overall survival. Concerning iCCA, large duct iCCA showed significantly higher 4-HNE levels when compared to small duct iCCA. Yet, in iCCA, 4-HNE levels did not correlate with known prognostic parameters or survival outcomes. To conclude, in HCC but not in iCCA, low amounts of 4-HNE predict unfavorable survival outcomes and are associated with aggressive tumor behavior. These findings provide insights into the role of 4-HNE in liver cancer progression and may enable novel therapeutic strategies.

p62 Promotes Survival and Hepatocarcinogenesis in Mice with Liver-Specific NEMO Ablation.

SQSTM1/p62 is a multitasking protein that functions as an autophagy receptor, but also as a signaling hub regulating diverse cellular pathways. p62 accumulation in mice with autophagy-deficient hepatocytes mediates liver damage and hepatocarcinogenesis through Nrf2 overactivation, yet the role of the p62-Keap1-Nrf2 axis in cell death and hepatocarcinogenesis in the absence of underlying autophagy defects is less clear. Here, we addressed the role of p62 and Nrf2 activation in a chronic liver disease model, namely mice with liver parenchymal cell-specific knockout of NEMO (NEMOLPC-KO), in which we demonstrate that they show no inherent autophagy impairment. Unexpectedly, systemic p62 ablation aggravated the phenotype and caused early postnatal lethality in NEMOLPC-KO mice. Expression of a p62 mutant (p62ΔEx2-5), which retains the ability to form aggregates and activate Nrf2 signaling, did not cause early lethality, but exacerbated hepatocarcinogenesis in these mice. Our immunohistological and molecular analyses showed that the increased tumor burden was only consistent with increased expression/stability of p62ΔEx2-5 driving Nrf2 hyperactivation, but not with other protumorigenic functions of p62, such as mTOR activation, cMYC upregulation or increased fibrosis. Surprisingly, forced activation of Nrf2 per se did not increase liver injury or tumor burden in NEMOLPC-KO mice, suggesting that autophagy impairment is a necessary prerequisite to unleash the Nrf2 oncogenic potential in mice with autophagy-competent hepatocytes.

PNPLA3(I148M) Inhibits Lipolysis by Perilipin-5-Dependent Competition with ATGL.

The single nucleotide polymorphism I148M of the lipase patatin-like phospholipase domain containing 3 (PNPLA3) is associated with an unfavorable prognosis in alcoholic and non-alcoholic steatohepatitis (ASH, NASH), with progression to liver cirrhosis and development of hepatocellular carcinoma. In this study, we investigated the mechanistic interaction of PNPLA3 with lipid droplet (LD)-associated proteins of the perilipin family, which serve as gatekeepers for LD degradation. In a collective of 106 NASH, ASH and control liver samples, immunohistochemical analyses revealed increased ballooning, inflammation and fibrosis, as well as an accumulation of PNPLA3-perilipin 5 complexes on larger LDs in patients homo- and heterozygous for PNPLA3(I148M). Co-immunoprecipitation demonstrated an interaction of PNPLA3 with perilipin 5 and the key enzyme of lipolysis, adipose triglyceride lipase (ATGL). Localization studies in cell cultures and human liver showed colocalization of perilipin 5, ATGL and PNPLA3. Moreover, the lipolytic activity of ATGL was negatively regulated by PNPLA3 and perilipin 5, whereas perilipin 1 displaced PNPLA3 from the ATGL complex. Furthermore, ballooned hepatocytes, the hallmark of steatohepatitis, were positive for PNPLA3 and perilipins 2 and 5, but showed decreased perilipin 1 expression with respect to neighboured hepatocytes. In summary, PNPLA3- and ATGL-driven lipolysis is significantly regulated by perilipin 1 and 5 in steatohepatitis.

Constitutive Occurrence of E:N-cadherin Heterodimers in Adherens Junctions of Hepatocytes and Derived Tumors.

Cell-cell junctions are pivotal for embryogenesis and tissue homeostasis but also play a major role in tumorigenesis, tumor invasion, and metastasis. E-cadherin (CDH1) and N-cadherin (CDH2) are two adherens junction's transmembrane glycoproteins with tissue-specific expression patterns in epithelial and neural/mesenchymal cells. Aberrant expression has been implicated in the process of epithelial-mesenchymal transition (EMT) in malignant tumors. We could hitherto demonstrate cis-E:N-cadherin heterodimer in endoderm-derived cells. Using immunoprecipitation in cultured cells of the line PLC as well as in human hepatocellular carcinoma (HCC)-lysates, we isolated E-N-cadherin heterodimers in a complex with the plaque proteins α- and ß-catenin, plakoglobin, and vinculin. In confocal laser scanning microscopy, E-cadherin co-localized with N-cadherin at the basolateral membrane of normal hepatocytes, hepatocellular adenoma (HCA), and in most cases of HCC. In addition, we analyzed E- and N-cadherin expression via immunohistochemistry in a large cohort of 868 HCCs from 570 patients, 25 HCA, and respective non-neoplastic liver tissue, and correlated our results with multiple prognostic markers. While E- or N-cadherin were similarly expressed in tumor sites with vascular invasion or HCC metastases, HCC with vascular encapsulated tumor clusters (VETC) displayed slightly reduced E-cadherin, and slightly increased N-cadherin expression. Analyzing The Cancer Genome Atlas patient cohort, we found that reduced mRNA levels of CDH1, but not CDH2 were significantly associated with unfavorable prognosis; however, in multivariate analysis, CDH1 did not correlate with prognosis. In summary, E- and N-cadherin are specific markers for hepatocytes and derived HCA and HCC. E:N-cadherin heterodimers are constitutively expressed in the hepatocytic lineage and only slightly altered in malignant progression, thereby not complying with the concept of EMT.

Transforming Growth Factor-ß Activated Kinase 1 (Tak1) Is Activated in Hepatocellular Carcinoma, Mediates Tumor Progression, and Predicts Unfavorable Outcome.

Although knowledge on inflammatory signaling pathways driving cancer initiation and progression has been increasing, molecular mechanisms in hepatocarcinogenesis are still far from being completely understood. Hepatocyte-specific deletion of the MAPKKK Tak1 in mice recapitulates important steps of hepatocellular carcinoma (HCC) development, including the occurrence of cell death, steatohepatitis, dysplastic nodules, and HCCs. However, overactivation of Tak1 in mice upon deletion of its deubiquitinase Cyld also results in steatohepatitis and HCC development. To investigate Tak1 and Cyld in human HCCs, we created a tissue microarray to analyze their expression by immunohistochemistry in a large and well-characterized cohort of 871 HCCs of 561 patients. In the human liver and HCC, Tak1 is predominantly present as its isoform Tak1A and predominantly localizes to cell nuclei. Tak1 is upregulated in diethylnitrosamine-induced mouse HCCs as well as in human HCCs independent of etiology and is further induced in distant metastases. A high nuclear Tak1 expression is associated with short survival and vascular invasion. When we overexpressed Tak1A in Huh7 cells, we observed increased tumor cell migration, whereas overexpression of full-length Tak1 had no significant effect. A combined score of low Cyld and high Tak1 expression was an independent prognostic marker in a multivariate Cox regression model.

13 C-Methacetin Breath Test Predicts Survival in Patients With Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization.

INTRODUCTION: The 13 C-methacetin breath test ( 13 C-MBT) is a dynamic method for assessing liver function. This proof-of-concept study aimed to investigate the association between 13 C-MBT values and outcomes in patients with hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE). METHODS: A total of 30 patients with HCC were prospectively recruited. Of these, 25 were included in baseline and 20 in longitudinal analysis. 13 C-MBTs were performed before the first and second TACE session. Patients were followed for at least 1 year. RESULTS: At baseline, the median 13 C-MBT value was 261 µg/kg/hr (interquartile range 159-387). 13 C-MBT, albumin-bilirubin, Child-Pugh, and Model for End-Stage Liver Disease scores were associated with overall survival in extended univariable Cox regression ( 13 C-MBT: standardized hazard ratio [sHR] 0.297, 95% confidence interval [CI] 0.111-0.796; albumin-bilirubin score: sHR 4.051, 95% CI 1.813-9.052; Child-Pugh score: sHR 2.616, 95% CI 1.450-4.719; Model for End-Stage Liver Disease score: sHR 2.781, 95% CI 1.356-5.703). Using a cutoff of 140 µg/kg/hr at baseline, 13 C-MBT was associated with prognosis (median overall survival 28.5 months [95% CI 0.0-57.1] vs 3.5 months [95% CI 0.0-8.1], log-rank P < 0.001). Regarding prediction of 90-day mortality after second 13 C-MBT, the relative change in 13 C-MBT values yielded an area under the receiver-operating characteristic curve of 1.000 ( P = 0.007). DISCUSSION: Baseline and longitudinal 13 C-MBT values predict survival of patients with HCC undergoing TACE. The relative change in 13 C-MBT values predicts short-term mortality and may assist in identifying patients who will not benefit from further TACE treatment.

NIK/MAP3K14 in hepatocytes orchestrates NASH to hepatocellular carcinoma progression via JAK2/STAT5 inhibition.

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) ranges from steatosis to nonalcoholic steatohepatitis (NASH), which often progresses to hepatocellular carcinoma (HCC) through a largely undefined mechanism. NASH and HCC depend on inflammatory signaling, whose master regulator is the NFκB transcription factor family, activated by canonical and non-canonical pathways. METHODS: Here, we investigated non-canonical NFκB-inducing kinase (NIK/MAP3K14) in metabolic NASH, NASH to HCC transition, and DEN-induced HCC. To this end, we performed dietary and chemical interventions in mice that were analyzed via single nucleus sequencing, gene expression and histochemical methods. Ultimately, we verified our mouse results in human patient samples. RESULTS: We revealed that hepatocyte-specific NIK deficiency (NIKLKO) ameliorated metabolic NASH complications and reduced hepatocarcinogenesis, independent of its role in the NFκB pathway. Instead, hepatic NIK attenuated hepatoprotective JAK2/STAT5 signaling that is a prerequisite for NASH and NASH to HCC progression in mice and humans. CONCLUSIONS: Our data suggest NIK-mediated inhibitory JAK2 phosphorylation at serine 633 that might be amenable for future therapeutic interventions in patients.

Key Enzymes in Pyrimidine Synthesis, CAD and CPS1, Predict Prognosis in Hepatocellular Carcinoma.

Patients with hepatocellular carcinoma (HCC) have a highly variable clinical course. Therefore, there is an urgent need to identify new prognostic markers to determine prognosis and select specific therapies. Recently, it has been demonstrated that dysregulation of the urea cycle (UC) is a common phenomenon in multiple types of cancer. Upon UC dysregulation, nitrogen is diverted toward the multifunctional enzyme carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, and dihydroorotase (CAD), and increases pyrimidine synthesis. In this study, we investigated the role of CAD and carbamoyl-phosphate synthetase 1 (CPS1), a rate-limiting enzyme of the UC highly expressed in hepatocytes, in HCC. We created a tissue microarray to analyze expression of both enzymes by immunohistochemistry in a large and well-characterized overall cohort of 871 HCCs of 561 patients that underwent surgery. CAD was induced in recurrent HCCs, and high expression predicted shorter overall survival. CPS1 was downregulated in HCC and further reduced in recurrent tumors and distant metastases. Additionally, low CPS1 was associated with short overall survival. A combined score of both enzymes was an independent prognostic marker in a multivariate Cox regression model (HR = 1.37, 95% confidence interval 1.06-1.75, p = 0.014). Inhibition of pyrimidine synthesis may represent a novel therapeutic strategy for HCC.

Pathology and biopsy assessment of non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent liver diseases in Western industrialized countries with dramatically rising incidence. The diagnosis of NAFLD requires the existence of steatosis in the absence of significant alcohol consumption. In cases of relevant inflammation pathogenetically linked to steatosis, it is termed non-alcoholic steatohepatitis (NASH). While pure steatosis represents a relatively harmless and rapidly reversible condition without a significant tendency to progression, NASH carries a significant morbidity and progression risk. Noninvasive methods neither reliably establish the diagnosis nor define the extent of disease in NASH, making histopathology the diagnostic gold standard. Since current therapeutic options in NASH are limited, indication for biopsy is made in the clinical context, predominantly in unclear clinical constellations, prior to invasive measures, for follow-up purposes and in the context of clinical studies. Histological hallmarks of NASH are steatosis, hepatocellular ballooning (with and without Mallory-Denk bodies), necroinflammation, and progressing disease a characteristic with perisinusoidal fibrosis. For semiquantitative assessment of necroinflammation (grading) and fibrosis (staging), a score has recently been implemented. Although histology does not reliably distinguish alcoholic steatohepatitis/alcoholic fatty liver disease from NASH/NAFLD, it may give valuable hints. NASH has a tendency for more steatosis, the so-called glycogenated nuclei, and less necroinflammatory activity. Future development of biopsy diagnosis will be coupled to the development of differential systemic therapeutic approaches. Especially in the context of clinical studies, detailed histological evaluation should be considered for the detection of predictive parameters.

Differential pattern of lipid droplet-associated proteins and de novo perilipin expression in hepatocyte steatogenesis.

Fatty change (steatosis) is the most frequent liver pathology in western countries and is caused by a broad range of disorders such as alcohol abuse and metabolic syndrome. The surface layer of lipid droplets (LDs) contains members of a protein family that share homologous sequences and domains, the so-called PAT proteins, named after their constituents, perilipin, adipophilin, and TIP47. We characterized the LD-associated proteins in normal and diseased liver connected with LD accumulation. Adipophilin and TIP47 are expressed in LDs of vitamin A-storing hepatic stellate cells and additionally in LDs of steatotic hepatocytes. Perilipin, which was thought to be characteristic for LDs of adipocytes and steroidogenic cells, becomes de novo expressed in hepatocytes of human steatotic liver. Perilipin splice variant A was found in human steatotic hepatocytes by biochemical, molecular biological, and immunohistochemical methods. Its association with LDs is different from TIP47 and adipophilin, and depends on size and localization of the LDs, suggesting that the different PAT proteins play specific roles during maturation of LDs.