Specific binding sites on Rhesus rotavirus capsid protein dictates the method of endocytosis inducing the murine model of biliary atresia.

Biliary atresia (BA) is the leading indication for pediatric liver transplantation. Rhesus rotavirus (RRV) induced murine BA develops an obstructive cholangiopathy that mirrors the human disease. We have previously demonstrated the "SRL" motif on RRV's VP4 protein binds to heat shock cognate 70 protein (Hsc70) facilitating entry into cholangiocytes. In this study, we analyzed how binding to Hsc70 affects viral endocytosis, intracellular trafficking, and uniquely activates the signaling pathway that induces murine BA. Inhibition of clathrin- and dynamin-mediated endocytosis in cholangiocytes following infection demonstrated blocking dynamin decreased the infectivity of RRV whereas clathrin inhibition had no effect. Blocking early endosome trafficking resulted in decreased viral titers of RRV while late endosome inhibition had no effect. Following infection, TLR3 expression and p-NF-κB levels increased in cholangiocytes, leading to increased release of CXCL9 and CXCL10. Infected mice knocked out for TLR3 had decreased levels of CXCL9 and CXCL10, resulting in reduced NK cell numbers. Human BA patients experienced an increase in CXCL10 levels, suggesting this as a possible pathway leading to biliary obstruction. Viruses that utilize Hsc70 for cell entry exploit a clathrin-independent pathway and traffic to the early recycling endosome uniquely activating NF-κB through TLR3, leading to the release of CXCL9 and CXCL10, and inducing NK cell recruitment. These results define how the "SRL" peptide found on RRV's VP4 protein modulates viral trafficking, inducing the host response leading to bile duct obstruction.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease.

BACKGROUND AND AIMS: Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis. APPROACH AND RESULTS: A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS. CONCLUSIONS: Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Management of undifferentiated embryonal sarcoma of the liver: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Undifferentiated embryonal sarcoma of the liver (UESL) is a rare tumor for which there are few evidence-based guidelines. The aim of this study was to define current management strategies and outcomes for these patients using a multi-institutional dataset curated by the Pediatric Surgical Oncology Research Collaborative. METHODS: Data were collected retrospectively for patients with UESL treated across 17 children's hospitals in North America from 1989 to 2019. Factors analyzed included patient and tumor characteristics, PRETEXT group, operative details, and neoadjuvant/adjuvant regimens. Event-free and overall survival (EFS, OS) were the primary and secondary outcomes, respectively. RESULTS: Seventy-eight patients were identified with a median age of 9.9 years [interquartile range [IQR): 7-12]. Twenty-seven patients underwent resection at diagnosis, and 47 patients underwent delayed resection, including eight liver transplants. Neoadjuvant chemotherapy led to a median change in maximum tumor diameter of 1.6 cm [IQR: 0.0-4.4] and greater than 90% tumor necrosis in 79% of the patients undergoing delayed resection. R0 resections were accomplished in 63 patients (81%). Univariate analysis found that metastatic disease impacted OS, and completeness of resection impacted both EFS and OS, while multivariate analysis revealed that R0 resection was associated with decreased expected hazards of experiencing an event [hazard ratio (HR): 0.14, 95% confidence interval (CI): 0.04-0.6]. At a median follow-up of 4 years [IQR: 2-8], the EFS was 70.0% [95% CI: 60%-82%] and OS was 83% [95% CI: 75%-93%]. CONCLUSION: Complete resection is associated with improved survival for patients with UESL. Neoadjuvant chemotherapy causes minimal radiographic response, but significant tumor necrosis.

Children's Oncology Group's 2023 blueprint for research: Liver tumors.

Liver tumors account for approximately 1%-2% of all pediatric malignancies, with the two most common tumors being hepatoblastoma (HB) and hepatocellular carcinoma (HCC). Previous Children's Oncology Group studies have meaningfully contributed to the current understanding of disease pathophysiology and treatment, laying groundwork for the ongoing prospective international study of both HB and HCC. Future work is focused on elucidating the biologic underpinnings of disease to support an evolution in risk categorization, advancements in the multidimensional care required to treat these patients, and the discovery of novel therapies.

Anti-thymocyte globulin induction with delayed introduction of tacrolimus preserves renal function in pediatric liver transplant recipients.

BACKGROUND: Tacrolimus (TAC)-mediated renal disease occurs in up to 70% of pediatric liver transplant (LT) recipients. The safety and efficacy of renal-sparing immunosuppression using anti-thymocyte globulin (ATG) induction and delayed TAC administration has not been studied in children. We evaluated the safety and efficacy of ATG induction on preserving renal function in children within the first year (Y1) post-LT in a single-center retrospective cohort study. METHODS: Children under age 18 years of who received isolated LT from 2008 to 2020 with a GFR < 70 received renal-sparing (RS) protocol consisting of ATG with methylprednisolone (MP), delayed TAC administration, lower initial TAC trough goals, and mycophenolate mofetil (MMF). The RS group was matched 1:2 by age and LT indication with standard immunosuppression (SI) group. Changes in renal function as well as adverse events within Y1 post-LT were compared. RESULTS: Forty-four pediatric patients were included in the analysis, of which 13 received RS. As expected, the RS group had significantly lower mean TAC trough levels at 30 days (10.3 vs. 13.2, p = .001) post-LT. Renal function was significantly preserved at 6 (-0.26 vs. 0.21, p = .004) and 12 months (-0.33 vs. 0.11, p = .003) post-LT in the RS versus SI group as measured by mean change in serum creatinine, with similar trends observed in eGFR and cystatin C. ACR, sepsis, viremia, graft loss and mortality occurred at similar rates in both RS and SI groups. CONCLUSION: Induction immunosuppression with ATG and delayed TAC administration in children with renal impairment is safe and effectively preserves renal function during Y1 post-LT.

Histologic type predicts disparate outcomes in pediatric hepatocellular neoplasms: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Hepatocellular carcinoma (HCC) is a rare cancer in children, with various histologic subtypes and a paucity of data to guide clinical management and predict prognosis. METHODS: A multi-institutional review of children with hepatocellular neoplasms was performed, including demographic, staging, treatment, and outcomes data. Patients were categorized as having conventional HCC (cHCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), and hepatoblastoma with HCC features (HB-HCC). Univariate and multivariate analyses identified predictors of mortality and relapse. RESULTS: In total, 262 children were identified; and an institutional histologic review revealed 110 cHCCs (42%; 69 normal background liver, 34 inflammatory/cirrhotic, 7 unknown), 119 FLCs (45%), and 33 HB-HCCs (12%). The authors observed notable differences in presentation and behavior among tumor subtypes, including increased lymph node involvement in FLC and higher stage in cHCC. Factors associated with mortality included cHCC (hazard ratio [HR], 1.63; P = .038), elevated α-fetoprotein (HR, 3.1; P = .014), multifocality (HR, 2.4; P < .001), and PRETEXT (pretreatment extent of disease) stage IV (HR, 5.76; P < .001). Multivariate analysis identified increased mortality in cHCC versus FLC (HR, 2.2; P = .004) and in unresectable tumors (HR, 3.4; P < .001). Disease-free status at any point predicted survival. CONCLUSIONS: This multi-institutional, detailed data set allowed a comprehensive analysis of outcomes for children with these rare hepatocellular neoplasms. The current data demonstrated that pediatric HCC subtypes are not equivalent entities because FLC and cHCC have distinct anatomic patterns and outcomes in concert with their known molecular differences. This data set will be further used to elucidate the impact of histology on specific treatment responses, with the goal of designing risk-stratified algorithms for children with HCC. LAY SUMMARY: This is the largest reported granular data set on children with hepatocellular carcinoma. The study evaluates different subtypes of hepatocellular carcinoma and identifies key differences between subtypes. This information is pivotal in improving understanding of these rare cancers and may be used to improve clinical management and subsequent outcome in children with these rare malignancies.

Hepatoblastomas with carcinoma features represent a biological spectrum of aggressive neoplasms in children and young adults.

BACKGROUND & AIMS: Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) are the predominant liver cancers in children, though their respective treatment options and associated outcomes differ dramatically. Risk stratification using a combination of clinical, histological, and molecular parameters can improve treatment selection, but it is particularly challenging for tumors with mixed histological features, including those in the recently created hepatocellular neoplasm not otherwise specified (HCN NOS) provisional category. We aimed to perform the first molecular characterization of clinically annotated cases of HCN NOS. METHODS: We tested whether these histological features are associated with genetic alterations, cancer gene dysregulation, and outcomes. Namely, we compared the molecular features of HCN NOS, including copy number alterations, mutations, and gene expression profiles, with those in other pediatric hepatocellular neoplasms, including HBs and HCCs, as well as HBs demonstrating focal atypia or pleomorphism (HB FPAs), and HBs diagnosed in older children (>8). RESULTS: Molecular profiles of HCN NOS and HB FPAs revealed common underlying biological features that were previously observed in HCCs. Consequently, we designated these tumor types collectively as HBs with HCC features (HBCs). These tumors were associated with high mutation rates (∼3 somatic mutations/Mb) and were enriched with mutations and alterations in key cancer genes and pathways. In addition, recurrent large-scale chromosomal gains, including gains of chromosomal arms 2q (80%), 6p (70%), and 20p (70%), were observed. Overall, HBCs were associated with poor clinical outcomes. CONCLUSIONS: Our study indicates that histological features seen in HBCs are associated with combined molecular features of HB and HCC, that HBCs are associated with poor outcomes irrespective of patient age, and that transplanted patients are more likely to have good outcomes than those treated with chemotherapy and surgery alone. These findings highlight the importance of molecular testing and early therapeutic intervention for aggressive childhood hepatocellular neoplasms. LAY SUMMARY: We molecularly characterized a class of histologically aggressive childhood liver cancers and showed that these tumors are clinically aggressive and that their observed histological features are associated with underlying recurrent molecular features. We proposed a diagnostic algorithm to identify these cancers using a combination of histological and molecular features, and our analysis suggested that these cancers may benefit from specialized treatment strategies that may differ from treatment guidelines for other childhood liver cancers.

High Mobility Group Box 1 Release by Cholangiocytes Governs Biliary Atresia Pathogenesis and Correlates With Increases in Afflicted Infants.

BACKGROUND AND AIMS: Biliary atresia (BA) is a devastating cholangiopathy of infancy. Upon diagnosis, surgical reconstruction by Kasai hepatoportoenterostomy (HPE) restores biliary drainage in a subset of patients, but most patients develop fibrosis and progress to end-stage liver disease requiring liver transplantation for survival. In the murine model of BA, rhesus rotavirus (RRV) infection of newborn pups results in a cholangiopathy paralleling that of human BA. High-mobility group box 1 (HMGB1) is an important member of the danger-associated molecular patterns capable of mediating inflammation during infection-associated responses. In this study, we investigated the role of HMGB1 in BA pathogenesis. APPROACH AND RESULTS: In cholangiocytes, RRV induced the expression and release of HMGB1 through the p38 mitogen-activated protein kinase signaling pathway, and inhibition of p38 blocked HMGB1 release. Treatment of cholangiocytes with ethyl pyruvate suppressed the release of HMGB1. Administration of glycyrrhizin in vivo decreased symptoms and increased survival in the murine model of BA. HMGB1 levels were measured in serum obtained from infants with BA enrolled in the PROBE and START studies conducted by the Childhood Liver Disease Research Network. High HMGB1 levels were found in a subset of patients at the time of HPE. These patients had higher bilirubin levels 3 months post-HPE and a lower survival of their native liver at 2 years. CONCLUSIONS: These results suggest that HMGB1 plays a role in virus induced BA pathogenesis and could be a target for therapeutic interventions in a subset of patients with BA and high HMGB1.

Children undergoing early liver re-transplantation for primary non-function have improved survival.

BACKGROUND: Primary non-function (PNF) in the early post-LT period in children leads to prolonged hospitalization, high graft loss, and significant mortality. However, there is a paucity of data available on the natural history of children relisted for LT due to PNF, including those who recover graft function and survive with their original allograft. METHODS: We interrogated the United Network of Organ Sharing (UNOS) database for pediatric LT recipients who were relisted with a primary diagnosis of PNF from 2000 to 2020. Patients >21-year-old and multiple organ transplants were excluded. Logistic regression and Cox proportional hazard models were employed to identify risk factors for early re-transplantation (within 30 days of relisting) and mortality after adjusting for baseline clinical characteristics. RESULTS: One hundred and eight patients were relisted for LT for PNF during the study period. Twenty-five patients survived beyond 30 days from relisting with their original LT, 76 underwent early re-transplantation, and 7 did not survive. Having a high-risk EBV mismatch (OR 2.03, 95% CI 0.66-6.27) and an elevated donor serum creatinine (OR: 2.19, 95% CI 0.54-8.84) were associated with increased odds of a patient requiring early re-transplantation. Donor characteristics including age, final total bilirubin, final AST/ALT, and final serum sodium, as well as vasopressor use prior to procurement, were not associated with increased odds of early re-transplantation (p > 0.05). Operative characteristics including allograft type and cold-ischemia time were also not associated with early re-transplantation (p > 0.05). Patients undergoing early re-transplantation showed a trend toward improved 1-year graft survival (69% vs 55%, p = 0.24). On multivariable Cox proportional hazards modeling, early re-transplantation was associated with reduced risk of overall patient mortality compared to those who survived with their original LT (HR 0.27, 95% CI 0.12-0.67). CONCLUSION: Early re-transplantation for PNF is associated with improved patient survival compared with patients who survive with their original LT.

Rotavirus Reassortant-Induced Murine Model of Liver Fibrosis Parallels Human Biliary Atresia.

BACKGROUND AND AIMS: Biliary atresia (BA) is a devastating neonatal cholangiopathy that progresses to fibrosis and end-stage liver disease by 2 years of age. Portoenterostomy may reestablish biliary drainage, but, despite drainage, virtually all afflicted patients develop fibrosis and progress to end-stage liver disease requiring liver transplantation for survival. APPROACH AND RESULTS: In the murine model of BA, rhesus rotavirus (RRV) infection of newborn pups results in a cholangiopathy paralleling human BA and has been used to study mechanistic aspects of the disease. Unfortunately, nearly all RRV-infected pups succumb by day of life 14. Thus, in this study we generated an RRV-TUCH rotavirus reassortant (designated as TR(VP2,VP4) ) that when injected into newborn mice causes an obstructive jaundice phenotype with lower mortality rates. Of the mice that survived, 63% developed Ishak stage 3-5 fibrosis with histopathological signs of inflammation/fibrosis and bile duct obstruction. CONCLUSIONS: This model of rotavirus-induced neonatal fibrosis will provide an opportunity to study disease pathogenesis and has potential to be used in preclinical studies with an objective to identify therapeutic targets that may alter the course of BA.

Clinical heterogeneity of pediatric hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is often a chemoresistant neoplasm with a poor prognosis. Pediatric HCC may reflect unique biological and clinical heterogeneity. PROCEDURE: An IRB-approved retrospective institutional review of patients with HCC treated between 2004 and 2015 was undertaken. Clinical, radiographic, and histologic data were collected from all patients. RESULTS: Thirty-two patients with HCC, median age 11.5 years (range 1-20) were identified. Seventeen patients had a genetic or anatomic predisposition. Histology was conventional HCC (25) and fibrolamellar HCC (7). Evans staging was 1 (12); 2 (1); 3 (10); 4 (9). Sixteen patients underwent resection at diagnosis and five patients after neoadjuvant chemotherapy. Surgical procedures included liver transplantation (LT, 11), hemihepatectomy (9), and segmentectomy (1). Eighteen patients had medical therapy (13 neoadjuvant, 5 adjuvant). Most common initial medical therapy included sorafenib alone (7) and cisplatin/doxorubicin-based therapy (8). Overall, 14 (43.8%) patients survived with a median follow-up of 58.8 months (range 26.5-157.6). Cause of death was most often linked to lack of primary tumor surgery (11). Of the survivors, Evans stage was 1 (11), 2 (1), and 3 (2, both treated with LT). Four of 18 patients (22%) who received medical therapy, 8 of 17 patients with a predisposition (47%), and 14 of 21 patients (66%) who underwent surgery remain alive. CONCLUSIONS: Genetic and anatomic predisposing conditions were seen in over half of this cohort. Evans stage 1 or 2 disease was linked to improved survival. LT trended toward improved survival. Use of known chemotherapy agents may benefit a smaller group of pediatric HCC and warrants formal prospective study through cooperative group trials.

Congenital Portosystemic Shunts in Children: Associations, Complications, and Outcomes.

BACKGROUND: Congenital portosystemic shunt (CPSS) is a rare malformation in which splanchnic venous flow bypasses the liver. CPSS is associated with other congenital anomalies and syndromes and can be associated with life-threatening complications. CPSS and their management remain underreported in the literature. Here, we review the clinical characteristics, management, and outcomes of a cohort of children and young adults with CPSS from two pediatric centers. METHODS: Cases of CPSS from Cincinnati Children's Hospital Medical Center and C.S. Mott Children's Hospital were reviewed to define CPSS anatomy, associated anomalies, complications, interventions, and outcomes. The imaging features and histopathology of liver lesions were characterized in detail. RESULTS: A total of 11 cases were identified. Median age was 10 years (range 0-26); 8 (73%) cases were female. Associated anomalies included six patients with heterotaxy (55%), five patients with congenital heart disease (45%), three patients with Turner syndrome (27%), and two patients with omphalocele, exstrophy, imperforate anus, spinal defects (OEIS) complex (18%). Eight (73%) cases had hyperammonemia ± encephalopathy. A 4-month-old presented with hepatopulmonary syndrome, and 12-year-old presented with pulmonary hypertension. Eight patients (73%) had liver lesions including five with premalignant adenomas and three with well-differentiated hepatocellular carcinoma (HCC). Four children underwent successful CPSS occlusion/ligation. Three children underwent liver transplant (2) or resection (1) for HCC without recurrence at extended follow-up. CONCLUSIONS: CPSS is associated with multiple anomalies (heterotaxy, congenital heart disease) and syndromes (Turner syndrome). CPSS liver lesions should be very carefully evaluated due to risk of premalignant adenomas and HCC. Serious complications of CPSS can occur at a young age but can be managed endovascularly or with open surgery.

Dose modifications and pharmacokinetics of adjuvant cisplatin monotherapy while on hemodialysis for patients with hepatoblastoma.

Hepatoblastoma can be associated with chronic kidney disease and genitourinary anomalies. Cisplatin is a key agent for treating hepatoblastoma but renal clearance and toxicity can limit its use in end-stage renal disease. We present pharmacokinetic data and clinical outcomes using cisplatin on hemodialysis for three patients with hepatoblastoma. All patients were initially treated with surgery and adjuvant cisplatin [1.67 mg/kg (2 patients) or 50 mg/m2 (1 patient)]. The patient treated with body surface area-based dosing had higher exposures and ototoxicity. Treating hepatoblastoma with cisplatin on hemodialysis using 1.67 mg/kg achieved clinical efficacy with minimal morbidity.

Surgical and anesthetic management for hepatectomy in two pediatric patients with trisomy 18, pulmonary hypertension, and hepatoblastoma.

Children with trisomy 18 are surviving longer and undergoing more aggressive life-sustaining therapy. This report describes two patients with trisomy 18 and hepatoblastoma (HB) successfully resected in the setting of significant pulmonary hypertension. Forty-four previously published cases of the association between HB and trisomy 18 are reviewed. With careful multidisciplinary preoperative planning, successful resection of HB in children with trisomy 18 who have significant pulmonary hypertension is feasible. Because HB and trisomy 18 are increasing in prevalence, the need for timely liver tumor resection in the setting of pulmonary hypertension will be more common.

Is anuria prior to pediatric renal transplantation associated with poor allograft outcomes?

INTRODUCTION: Anuria from end-stage renal disease leads to a defunctionalized bladder and may pose technical challenges at the time of renal transplantation. Anuria's effect on bladder function after renal transplantation is considered to be minimal in adults, although a paucity of evidence is available in children. The purpose of this study was to examine the effects of anuria prior to pediatric renal transplantation for ESRD due to medical renal disease on allograft outcome. METHODS: We performed a retrospective review of pediatric patients who underwent renal transplantation for medical renal disease at our institution between 2005 and 2016. Demographics and clinical data were assessed. We also compared GFR at 1 year post-transplant for medical renal patients with history of anuria and those without. RESULTS: Twenty-one patients fulfilled our inclusion criteria with median duration of anuria was 10 months. Preoperative VCUG was available in five patients and their bladder capacity was 29% of expected bladder capacity for age (range 8%-41%). Anticholinergic therapy was prescribed in six patients (28%) for a mean duration of 5 months (range 1-16 months). Comparison of GFR at 1 year post-transplant in anuria group and those without anuria showed no difference (69 vs 75 mL/min, P = 0.37). No correlation was observed between duration of anuria and post-transplant GFR. CONCLUSION: The majority of children in our pretransplant anuria cohort did not develop bladder dysfunction after renal transplantation. No difference was observed between GFR at 1 year when comparing anuric to non-anuric transplant recipients of medical renal disease etiology.

A Point Mutation in the Rhesus Rotavirus VP4 Protein Generated through a Rotavirus Reverse Genetics System Attenuates Biliary Atresia in the Murine Model.

Rotavirus infection is one of the most common causes of diarrheal illness in humans. In neonatal mice, rhesus rotavirus (RRV) can induce biliary atresia (BA), a disease resulting in inflammatory obstruction of the extrahepatic biliary tract and intrahepatic bile ducts. We previously showed that the amino acid arginine (R) within the sequence SRL (amino acids 445 to 447) in the RRV VP4 protein is required for viral binding and entry into biliary epithelial cells. To determine if this single amino acid (R) influences the pathogenicity of the virus, we generated a recombinant virus with a single amino acid mutation at this site through a reverse genetics system. We demonstrated that the RRV mutant (RRVVP4-R446G) produced less symptomatology and replicated to lower titers both in vivo and in vitro than those seen with wild-type RRV, with reduced binding in cholangiocytes. Our results demonstrate that a single amino acid change in the RRV VP4 gene influences cholangiocyte tropism and reduces pathogenicity in mice.IMPORTANCE Rotavirus is the leading cause of diarrhea in humans. Rhesus rotavirus (RRV) can also lead to biliary atresia (a neonatal human disease) in mice. We developed a reverse genetics system to create a mutant of RRV (RRVVP4-R446G) with a single amino acid change in the VP4 protein compared to that of wild-type RRV. In vitro, the mutant virus had reduced binding and infectivity in cholangiocytes. In vivo, it produced fewer symptoms and lower mortality in neonatal mice, resulting in an attenuated form of biliary atresia.

The SRL peptide of rhesus rotavirus VP4 protein governs cholangiocyte infection and the murine model of biliary atresia.

Biliary atresia (BA) is a neonatal obstructive cholangiopathy that progresses to end-stage liver disease, often requiring transplantation. The murine model of BA, employing rhesus rotavirus (RRV), parallels human disease and has been used to elucidate mechanistic aspects of a virus induced biliary cholangiopathy. We previously reported that the RRV VP4 gene plays an integral role in activating the immune system and induction of BA. Using rotavirus binding and blocking assays, this study elucidated how RRV VP4 protein governs cholangiocyte susceptibility to infection both in vitro and in vivo in the murine model of BA. We identified the amino acid sequence on VP4 and its cholangiocyte binding protein, finding that the sequence is specific to those rotavirus strains that cause obstructive cholangiopathy. Pretreatment of murine and human cholangiocytes with this VP4-derived peptide (TRTRVSRLY) significantly reduced the ability of RRV to bind and infect cells. However, the peptide did not block cholangiocyte binding of TUCH and Ro1845, strains that do not induce murine BA. The SRL sequence within TRTRVSRLY is required for cholangiocyte binding and viral replication. The cholangiocyte membrane protein bound by SRL was found to be Hsc70. Inhibition of Hsc70 by small interfering RNAs reduced RRV's ability to infect cholangiocytes. This virus-cholangiocyte interaction is also seen in vivo in the murine model of BA, where inoculation of mice with TRTRVSRLY peptide significantly reduced symptoms and mortality in RRV-injected mice. CONCLUSION: The tripeptide SRL on RRV VP4 binds to the cholangiocyte membrane protein Hsc70, defining a novel binding site governing VP4 attachment. Investigations are underway to determine the cellular response to this interaction to understand how it contributes to the pathogenesis of BA. (Hepatology 2017;65:1278-1292).

Analysis of surgical interruption of the enterohepatic circulation as a treatment for pediatric cholestasis.

To evaluate the efficacy of nontransplant surgery for pediatric cholestasis, 58 clinically diagnosed children, including 20 with Alagille syndrome (ALGS), 16 with familial intrahepatic cholestasis-1 (FIC1), 18 with bile salt export pump (BSEP) disease, and 4 others with low γ-glutamyl transpeptidase disease (levels <100 U/L), were identified across 14 Childhood Liver Disease Research Network (ChiLDReN) centers. Data were collected retrospectively from individuals who collectively had 39 partial external biliary diversions (PEBDs), 11 ileal exclusions (IEs), and seven gallbladder-to-colon (GBC) diversions. Serum total bilirubin decreased after PEBD in FIC1 (8.1 ± 4.0 vs. 2.9 ± 4.1 mg/dL, preoperatively vs. 12-24 months postoperatively, respectively; P = 0.02), but not in ALGS or BSEP. Total serum cholesterol decreased after PEBD in ALGS patients (695 ± 465 vs. 457 ± 319 mg/dL, preoperatively vs. 12-24 months postoperatively, respectively; P = 0.0001). Alanine aminotransferase levels increased in ALGS after PEBD (182 ± 70 vs. 260 ± 73 IU/L, preoperatively vs. 24 months; P = 0.03), but not in FIC1 or BSEP. ALGS, FIC1, and BSEP patients experienced less severely scored pruritus after PEBD (ALGS, 100% vs. 9% severe; FIC1, 64% vs. 10%; BSEP, 50% vs. 20%, preoperatively vs. >24 months postoperatively, respectively; P < 0.001). ALGS patients experienced a trend toward greater freedom from xanthomata after PEBD. There was a trend toward decreased pruritus in FIC1 after IE and GBC. Vitamin K supplementation increased in ALGS after PEBD (33% vs. 77%; P = 0.03). Overall, there were 15 major complications after surgery. Twelve patients (3 ALGS, 3 FIC1, and 6 BSEP) subsequently underwent liver transplantation. CONCLUSION: This was a multicenter analysis of nontransplant surgical approaches to intrahepatic cholestasis. Approaches vary, are well tolerated, and generally, although not uniformly, result in improvement of pruritus and cholestasis. (Hepatology 2017;65:1645-1654).

Germline APC mutations in hepatoblastoma.

BACKGROUND: Conflicting reports on the frequency of germline adenomatous polyposis coli (APC) gene mutations in patients with hepatoblastoma (HB) have called into question the clinical value of APC mutation testing on apparently sporadic HB. METHODS: An Institutional Review Board approved retrospective review of clinical data collected from patients with HB who received APC testing at our institution was conducted. All HB patients seen at Cincinnati Children's Hospital Medical Center were eligible for testing. Potential genotype/phenotype correlations were assessed. RESULTS: As of July 2015, 29 patients with HB had received constitutional APC testing. Four (14%) were found to have APC pathogenic truncations of the APC protein and in addition two (7%) had APC missense variants of unknown clinical significance. Two patients (7%) had family histories indicative of familial adenomatous polyposis (FAP). Response to chemotherapy tracked differently in APC pathogenic cases, with a slower imaging response despite an equivalent or slightly faster α-fetoprotein (AFP) response. CONCLUSION: The prevalence of pathogenic APC variants in apparently sporadic HB may be higher than previously detected. Differences in time to imaging response, despite similar AFP response, may impact surgical planning. All patients with HB warrant germline APC mutation testing for underlying FAP.

Surgical management of children and adolescents with upfront completely resected hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is an aggressive malignant neoplasm that is often chemoresistant. Complete surgical resection remains the mainstay of therapy. The role of liver transplantation (LT) in pediatric HCC is in evolution, as is the role of adjuvant chemotherapy for stage I disease. METHODS: A retrospective review of patients < 18 years of age with completely resected HCC treated with surgical intervention alone at our institution from 2004 to 2015 was conducted. RESULTS: Twelve patients with a median age of 12 years (range = 1-17; number of females = 7) with upfront resected HCC (Evans stage I) were identified. Four patients had HCC without identifiable risk factors (fibrolamellar-HCC = 2; early HCC arising in focal nodular hyperplasia = 1, well-differentiated [wd] HCC = 1). Four patients had early or wd-HCC in the context of portosystemic shunts (Abernethy = 2; mesocaval shunt and portal vein thrombosis = 2). Four patients had moderate to wd-HCC in the context of pre-existing liver disease with cirrhosis (progressive familial intrahepatic cholestasis type-2 = 2, alpha-1 antitrypsin deficiency = 1, Alagille syndrome = 1). Seven patients underwent LT (multifocal = 5; solitary = 2); five exceeded Milan criteria (MC) by imaging. Five patients underwent complete resection (segmentectomy = 2; hemihepatectomy = 3). Ten patients received no adjuvant chemotherapy. All patients are alive without evidence of disease with a median follow-up of 54.1 months (range = 28.1-157.7 months). CONCLUSIONS: Pediatric and adolescent patients with upfront, completely resected HCC can be effectively treated without chemotherapy. LT should be considered for nonmetastatic HCC, especially in the context of pre-existing chronic liver disease, even when the tumor exceeds MC. Distinct pediatric selection criteria are needed to identify patients most suitable for LT.