Optimal Timing of Administration of Direct-acting Antivirals for Patients With Hepatitis C-associated Hepatocellular Carcinoma Undergoing Liver Transplantation

OBJECTIVE

To investigate the optimal timing of direct acting antiviral (DAA) administration in patients with hepatitis C-associated hepatocellular carcinoma (HCC) undergoing liver transplantation (LT).

SUMMARY OF BACKGROUND DATA

In patients with hepatitis C (HCV) associated HCC undergoing LT, the optimal timing of direct-acting antivirals (DAA) administration to achieve sustained virologic response (SVR) and improved oncologic outcomes remains a topic of much debate.

METHODS

The United States HCC LT Consortium (2015-2019) was reviewed for patients with primary HCV-associated HCC who underwent LT and received DAA therapy at 20 institutions. Primary outcomes were SVR and HCC recurrence-free survival (RFS).

RESULTS

Of 857 patients, 725 were within Milan criteria. SVR was associated with improved 5-year RFS (92% vs 77%, P < 0.01). Patients who received DAAs pre-LT, 0-3 months post-LT, and ≥3 months post-LT had SVR rates of 91%, 92%, and 82%, and 5-year RFS of 93%, 94%, and 87%, respectively. Among 427 HCV treatment-naïve patients (no previous interferon therapy), patients who achieved SVR with DAAs had improved 5-year RFS (93% vs 76%, P < 0.01). Patients who received DAAs pre-LT, 0-3 months post-LT, and ≥3 months post-LT had SVR rates of 91%, 93%, and 78% (P < 0.01) and 5-year RFS of 93%, 100%, and 83% (P = 0.01).

CONCLUSIONS

The optimal timing of DAA therapy appears to be 0 to 3 months after LT for HCV-associated HCC, given increased rates of SVR and improved RFS. Delayed administration after transplant should be avoided. A prospective randomized controlled trial is warranted to validate these results.

High-resolution phenotyping of early acute rejection reveals a conserved alloimmune signature

Alloimmune responses in acute rejection are complex, involving multiple interacting cell types and pathways. Deep profiling of these cell types has been limited by technology that lacks the capacity to resolve this high dimensionality. Single-cell mass cytometry is used to characterize the alloimmune response in early acute rejection, measuring 37 parameters simultaneously, across multiple time points in two models: a murine cardiac and vascularized composite allotransplant (VCA). Semi-supervised hierarchical clustering is used to group related cell types defined by combinatorial expression of surface and intracellular proteins, along with markers of effector function and activation. This expression profile is mapped to visualize changes in antigen composition across cell types, revealing phenotypic signatures in alloimmune T cells, natural killer (NK) cells, and myeloid subsets that are conserved and that firmly distinguish rejecting from non-rejecting grafts. These data provide a comprehensive, high-dimensional profile of cellular rejection after allograft transplantation.

Predictors of Outcomes of Patients Referred to a Transplant Center for Urgent Liver Transplantation Evaluation

Liver transplantation (LT) is definitive treatment for end-stage liver disease. This study evaluated factors predicting successful evaluation in patients transferred for urgent inpatient LT evaluation. Eighty-two patients with cirrhosis were transferred for urgent LT evaluation from January 2016 to December 2018. Alcohol-associated liver disease was the common etiology of liver disease (42/82). Of these 82 patients, 35 (43%) were declined for LT, 27 (33%) were wait-listed for LT, 5 (6%) improved, and 15 (18%) died. Psychosocial factors were the most common reasons for being declined for LT (49%). Predictors for listing and receiving LT on multivariate analysis included Hispanic race (odds ratio [OR], 1.89; P = 0.003), Asian race (OR, 1.52; P = 0.02), non-Hispanic ethnicity (OR, 1.49; P = 0.04), hyponatremia (OR, 1.38; P = 0.04), serum albumin (OR, 1.13; P = 0.01), and Model for End-Stage Liver Disease (MELD)-Na (OR, 1.02; P = 0.003). Public insurance (i.e., Medicaid) was a predictor of not being listed for LT on multivariate analysis (OR, 0.77; P = 0.02). Excluding patients declined for psychosocial reasons, predictors of being declined for LT on multivariate analysis included Chronic Liver Failure Consortium (CLIF-C) score >51.5 (OR, 1.26; P = 0.03), acute-on-chronic liver failure (ACLF) grade 3 (OR, 1.41; P = 0.01), hepatorenal syndrome (HRS) (OR, 1.38; P = 0.01), and respiratory failure (OR, 1.51; P = 0.01). Predictors of 3-month mortality included CLIF-C score >51.5 (hazard ratio [HR], 2.52; P = 0.04) and intensive care unit (HR, 8.25; P < 0.001). Conclusion: MELD-Na, albumin, hyponatremia, ACLF grade 3, HRS, respiratory failure, public insurance, Hispanic race, Asian race, and non-Hispanic ethnicity predicted liver transplant outcome. Lack of psychosocial support was a major reason for being declined for LT. The CLIF-C score predicted being declined for LT and mortality.

Establishment of Heterotopic Hind Limb Transplantation Model in the Mouse

BACKGROUND

The mouse is the most widely used animal for establishing in vivo models in transplant research. However, because of the advanced microsurgical skills required for these operations, the vascularized composite transplantation model in mouse has proven to be technically challenging. The purpose of this report is to describe novel modifications in surgical techniques to establish a consistent and reliable mouse model of hind limb transplantation.

METHODS

Forty C57BL/6 male mice, half as donors and half as recipients, were used in this study. The donor hind limb was harvested and transplanted into the recipient's ipsilateral cervical region by anastomosing the donor femoral artery to the recipient common carotid artery with a modified sleeve technique. The donor femoral vein was mounted with a modified cuff and inserted into the recipient external jugular vein. The graft was evaluated at 2 weeks postoperatively.

RESULTS

The modified cuff and modified sleeve technique facilitated anastomoses. The time spent on either of the donor operation and recipient operation was about 45 minutes. The graft survival rate was 80% (16 of 20) at 2 weeks after transplant. There was minimal blood loss and no infections were noted.

CONCLUSIONS

Revised surgical techniques using a modified cuff proved to be a safe, reliable, and reproducible strategy in establishing a mouse model of hind limb heterotopic transplantation. The consistent graft survival in this syngeneic study demonstrates that this model can serve as a useful tool for further studies in vascularized composite transplantation.

Epstein-Barr virus peptides derived from latent cycle proteins alter NKG2A + NK cell effector function

Natural killer (NK) cells control viral infection through the interaction between inhibitory receptors and human leukocyte antigen (HLA) ligands and bound peptide. NK cells expressing the inhibitory receptor NKG2A/CD94 recognize and respond to autologous B cells latently infected with Epstein-Barr virus (EBV). The mechanism is not yet understood, thus we investigated peptides derived from seven latent proteins of EBV in the interaction of NKG2A and its ligand HLA-E. Functional analysis demonstrated that EBV peptides can bind to HLA-E and block inhibition of NK cell effector function. Moreover, analysis of DNA from 79 subjects showed sequence variations in the latent protein, LMP1, which alters NK responses to EBV. We provide evidence that peptides derived from EBV latent cycle proteins can impair the recognition of NKG2A despite being presented by HLA-E, resulting in NK cell activation.

Successful liver transplantation in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE)

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a fatal disorder characterized by progressive gastrointestinal dysmotility, peripheral neuropathy, leukoencephalopathy, skeletal myopathy, ophthalmoparesis, and ptosis. MNGIE stems from deficient thymidine phosphorylase activity (TP) leading to toxic elevations of plasma thymidine. Hematopoietic stem cell transplant (HSCT) restores TP activity and halts disease progression but has high transplant-related morbidity and mortality. Liver transplant (LT) was reported to restore TP activity in two adult MNGIE patients. We report successful LT in four additional MNGIE patients, including a pediatric patient. Our patients were diagnosed between ages 14 months and 36 years with elevated thymidine levels and biallelic pathogenic variants in TYMP. Two patients presented with progressive gastrointestinal dysmotility, and three demonstrated progressive peripheral neuropathy with two suffering limitations in ambulation. Two patients, including the child, had liver dysfunction and cirrhosis. Following LT, thymidine levels nearly normalized in all four patients and remained low for the duration of follow-up. Disease symptoms stabilized in all patients, with some manifesting improvements, including intestinal function. No patient died, and LT appeared to have a more favorable safety profile than HSCT, especially when liver disease is present. Follow-up studies will need to document the long-term impact of this new approach on disease outcome. Take Home Message: Liver transplantation is effective in stabilizing symptoms and nearly normalizing thymidine levels in patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) and may have an improved safety profile over hematopoietic stem cell transplant.

Genomic variations in EBNA3C of EBV associate with posttransplant lymphoproliferative disorder

Epstein-Barr Virus (EBV) is a ubiquitous virus linked to a variety of lymphoid and epithelial malignancies. In solid organ and hematopoietic stem cell transplant recipients, EBV is causally associated with posttransplant lymphoproliferative disorder (PTLD), a group of heterogeneous lymphoid diseases. EBV+ B cell lymphomas that develop in the context of PTLD are generally attributed to the immunosuppression required to promote graft survival, but little is known regarding the role of EBV genome diversity in the development of malignancy. We deep-sequenced the EBV genome from the peripheral blood of 18 solid organ transplant recipients, including 6 PTLD patients. Sequences from 6 EBV+ spontaneous lymphoblastoid B cell lines (SLCL) were similarly analyzed. The EBV genome from PTLD patients had a significantly greater number of variations than EBV from transplant recipients without PTLD. Importantly, there were 15 nonsynonymous variations, including 8 in the latent cycle gene EBNA3C that were associated with the development of PTLD. One of the nonsynonymous variations in EBNA3C is located within a previously defined T cell epitope. These findings suggest that variations in the EBV genome can contribute to the pathogenesis of PTLD.

Eliminating international normalized ratio threshold for transfusion in pediatric patients with acute liver failure

INTRODUCTION

Transfusion protocols are not well-studied for pediatric patients with acute liver failure (ALF). This study evaluates the utility of an international normalized ratio (INR)-based transfusion threshold for these patients.

METHODS

Forty-four ALF pediatric patients from 2009 to 2018 were reviewed and divided into two groups: (a) a threshold group including patients between 2009 and 2015 who were transfused for an INR above 3.0, per institutional policy (n = 30), and (b) a post-threshold group including patients after 2015 through 2018 who were transfused based on clinical judgment (n = 14). Preoperative INRs, preoperative transfusions, intraoperative transfusions, early reoperation, renal function, graft function and deaths were compared.

RESULTS

Liver failure severity was similar between threshold and post-threshold groups. Threshold patients had a lower average INR prior to transplantation, 2.8 (range 1.8-3.8) vs 4.4 (range 2.1-9.0), respectively (P = .01). Twenty-six threshold patients (87%) received preoperative FFP compared with seven post-threshold patients (50%, P = .0088). Two threshold patients (7%) received preoperative cryoprecipitate compared with five post-threshold patients (36%, P = .014). The incidence of pre-transplant bleeding, operative transfusions, and 1-year patient and graft survival did not differ significantly.

CONCLUSION

Clinical judgment vs an INR-based threshold for transfusions did not increase perioperative complications in children with ALF.

Differential role of natural killer group 2D in recognition and cytotoxicity of hepatocyte-like cells derived from embryonic stem cells and induced pluripotent stem cells

Stem cell-based approaches have the potential to address the organ shortage in transplantation. Whereas both embryonic stem cells and induced pluripotent stem cells have been utilized as cellular sources for differentiation and lineage specification, their relative ability to be recognized by immune effector cells is unclear. We determined the expression of immune recognition molecules on hepatocyte-like cells (HLC) generated from murine embryonic stem cells and induced pluripotent stem cells, compared to adult hepatocytes, and we evaluated the impact on recognition by natural killer (NK) cells. We report that HLC lack MHC class I expression, and that embryonic stem cell-derived HLC have higher expression of the NK cell activating ligands Rae1, H60, and Mult1 than induced pluripotent stem cell-derived HLC and adult hepatocytes. Moreover, the lack of MHC class I renders embryonic stem cell-derived HLC, and induced pluripotent stem cell-derived HLC, susceptible to killing by syngeneic and allogeneic NK cells. Both embryonic stem cell-derived HLC, and induced pluripotent stem cell-derived HLC, are killed by NK cells at higher levels than adult hepatocytes. Finally, we demonstrate that the NK cell activation receptor, NKG2D, plays a key role in NK cell cytotoxicity of embryonic stem cell-derived HLC, but not induced pluripotent stem cell-derived HLC.

Dual blockade of the PI3K/Akt/mTOR pathway inhibits posttransplant Epstein-Barr virus B cell lymphomas and promotes allograft survival

Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of organ transplantation that often manifests as Epstein-Barr virus (EBV)-associated B cell lymphomas. Current treatments for PTLD have limited efficacy and can be associated with graft rejection or systemic toxicities. The mTOR inhibitor, rapamycin, suppresses tumor growth of EBV+ B cell lymphoma cells in vitro and in vivo; however, the efficacy is limited and clinical benefits of mTOR inhibitors for PTLD are variable. Here, we show constitutive activation of multiple nodes within the PI3K/Akt/mTOR pathway in EBV+ PTLD-derived cell lines. Inhibition of either PI3K or Akt, with specific inhibitors CAL-101 and MK-2206, respectively, diminished growth of EBV+ B cell lines from PTLD patients in a dose-dependent manner. Importantly, rapamycin combined with CAL-101 or MK-2206 had a synergistic effect in suppressing cell growth as determined by IC₅₀ isobolographic analysis and Loewe indices. Moreover, these combinations were significantly more effective than rapamycin alone in inhibiting tumor xenograft growth in NOD-SCID mice. Finally, both CAL-101 and MK-2206 also prolonged survival of heterotopic cardiac allografts in C57BL/6 mice. Thus, combination therapy with rapamycin and a PI3K inhibitor, or an Akt inhibitor, can be an efficacious treatment for EBV-associated PTLD, while simultaneously promoting allograft survival.

Orthotopic Liver Transplantation After Stereotactic Body Radiotherapy for Pediatric Hepatocellular Carcinoma with Central Biliary Obstruction and Nodal Involvement

Here we describe the case of a 10-year-old boy with a history of chronic hepatitis B who was diagnosed with hepatocellular carcinoma (HCC) with a large central hepatic mass and metastatic disease in a celiac lymph node. His tumor was unresectable, due to location and lack of clear margins, and he could not receive chemotherapy due to elevated bilirubin. He was treated with stereotactic body radiotherapy (SBRT) to the primary site and involved nodal region. After completing radiotherapy, his total bilirubin level fell below 1.0 mg/dL, allowing him to begin systemic therapy with cisplatin and doxorubicin. At three months after SBRT, his bilirubin was 0.1 mg/dL, alpha-fetoprotein (AFP) was 88 ng/mL, and imaging demonstrated a decrease in tumor size (total volume 28.7 cc), with no evidence of local or distant disease progression. He then developed distant disease within the liver, but his disease remained controlled at the primary site and nodes that had been treated with SBRT. He underwent orthotopic liver transplantation (OLT) with an uneventful operative course and remains with no evidence of disease at seven months after OLT. This is one of the first reported cases of successful downstaging of pediatric HCC with nodal involvement to allow for OLT, and it argues for consideration of similar patients for OLT.

The Effect of Serotonin Inhibition on Initial Microvessel Hemostasis and Platelet Aggregation In Vivo

The role of serotonin (5-HT) in initial microvascular hemostasis is not fully understood. This study was made to evaluate the effect on hemostatic plug formation and laser-induced arteriolar microembolism of different substances which counteract the effect of 5-HT. Hemostatic plug formation time and stability was measured in the rabbit mesenteric microcirculation and laserinduced embolism in the rabbit ear chamber. Ketanserine, a selective 5-HT2-receptor blocker shortened arteriolar hemostatic plug formation time. Dihydroergotamine, an unselective blocker (with 5-HT- and α-adrenergic receptor affinity) increased venular hemostatic plug formation time and also decreased the hemostatic plug stability. Laser-induced platelet embolism was unaltered after both ketanserine and dihydroergotamine administration. The magnitude of these changes seems to exclude an important effect of 5-HT in initial microvessel hemostasis or on platelet activity.

Assessment of Antithrombotic Properties of Sodium Ibuprofen

The effect of sodium ibuprofen on platelet activity in vivo and the lysability of ex vivo thrombi was investigated. The formation of a hemostatic platelet plug in the rabbit mesentery and platelet embolism as a response to a laser-induced injury in the ear chamber of rabbits were used as models for determining platelet activity. Ibuprofen at a dose of 25 mg/kg i.v. was found to increase the primary (PHT) and the total hemostatic plug formation time (THT). The same dose decreased the number of cumulative emboli over a 10 min period after a laser injury to arterioles. A dose of 10 mg/kg i.v. did not affect the formation of the hemostatic platelet plug. In dogs, doses of 10, 25 und 50 mg/kg did not enhance the release of 125I-FDP from the thrombi after incubation in plasmin, but the largest dose which is approximately five times the recommended dose in humans, did significantly decrease the thrombus weight 90 and 180 min after the drug administration. In conclusion, sodium ibuprofen was shown to have an inhibitory effect on platelet function in vivo and in large doses was also found to diminish the thrombus weight.

Transarterial chemoembolization in children to treat unresectable hepatocellular carcinoma

Children with unresectable HCC have a dismal prognosis and few approved treatment options. TACE is an effective treatment option for adults with HCC, but experience in children is very limited. Retrospective analysis was performed of 8 patients aged 4-17 years (4 male, mean 12.5 years) who underwent TACE for unresectable HCC. Response to TACE was evaluated by change in AFP, RECIST and tumor volume, PRETEXT, and transplantation eligibility by UCSF and Milan criteria. Post-procedure mean follow-up was 8.2 years. Mean overall change in tumor volume for the 8 patients was 51%. Percent change in AFP ranged from a decrease of 100% to an increase of 89.3%, with a mean change of -49.6%. Two patients did not undergo resection or transplantation and died of progressive disease. Six patients underwent orthotopic liver transplantation with mean first TACE-to-transplant interval of 141 days (range 11-514). Following transplantation, 5 patients were alive at the end of the follow-up period and one died of recurrent disease. Based on our initial experience, TACE for children with unresectable HCC appears to be a safe and effective method for managing hepatic tumor burden and for downstaging and bridging to liver transplantation.

Prenatal treatment of ornithine transcarbamylase deficiency

PURPOSE OF STUDY

Patients with neonatal urea cycle defects (UCDs) typically experience severe hyperammonemia during the first days of life, which results in serious neurological injury or death. Long-term prognosis despite optimal pharmacological and dietary therapy is still poor. The combination of intravenous sodium phenylacetate and sodium benzoate (Ammonul®) can eliminate nitrogen waste independent of the urea cycle. We report attempts to improve outcomes for males with severe ornithine transcarbamylase deficiency (OTCD), a severe X-linked condition, via prenatal intravenous administration of Ammonul and arginine to heterozygous carrier females of OTCD during labor.

METHODS USED

Two heterozygote OTCD mothers carrying male fetuses with a prenatal diagnosis of OTCD received intravenous Ammonul, arginine and dextrose-containing fluids shortly before birth. Maintenance Ammonul and arginine infusions and high-caloric enteral nutrition were started immediately after birth. Ammonul metabolites were measured in umbilical cord blood and the blood of the newborn immediately after delivery. Serial ammonia and biochemical analyses were performed following delivery.

SUMMARY OF RESULTS

Therapeutic concentrations of Ammonul metabolites were detected in umbilical cord and neonatal blood samples. Plasma ammonia and glutamine levels in the postnatal period were within the normal range. Peak ammonia levels in the first 24-48h were 53mcmol/l and 62mcmol/l respectively. The boys did not experience neurological sequelae secondary to hyperammonemia and received liver transplantation at ages 3months and 5months. The patients show normal development at ages 7 and 3years.

CONCLUSION

Prenatal treatment of mothers who harbor severe OTCD mutations and carry affected male fetuses with intravenous Ammonul and arginine, followed by immediate institution of maintenance infusions after delivery, results in therapeutic levels of benzoate and phenylacetate in the newborn at delivery and, in conjunction with high-caloric enteral nutrition, prevents acute hyperammonemia and neurological decompensation. Following initial medical management, early liver transplantation may improve developmental outcome.

Dynamics of Viral and Host Immune Cell MicroRNA Expression during Acute Infectious Mononucleosis

Epstein–Barr virus (EBV) is the etiological agent of acute infectious mononucleosis (IM). Since acute IM is a self-resolving disease with most patients regaining health in 1–3 weeks there have been few studies examining molecular signatures in early acute stages of the disease. MicroRNAs (miRNAs) have been shown, however, to influence immune cell function and consequently the generation of antibody responses in IM. In this study, we performed a comprehensive analysis of differentially expressed miRNAs in early stage uncomplicated acute IM. miRNAs were profiled from patient peripheral blood obtained at the time of IM diagnosis and at subsequent time points, and pathway analysis performed to identify important immune and cell signaling pathways. We identified 215 differentially regulated miRNAs at the most acute stage of infection when the patients initially sought medical help. The number of differentially expressed miRNAs decreased to 148 and 68 at 1 and 2 months post-primary infection, with no significantly changed miRNAs identified at 7 months post-infection. Interferon signaling, T and B cell signaling and antigen presentation were the top pathways influenced by the miRNAs associated with IM. Thus, a dynamic and regulated expression profile of miRNA accompanies the early acute immune response, and resolution of infection, in IM.

Mass cytometry reveals a distinct immunoprofile of operational tolerance in pediatric liver transplantation

Long-term IS in transplant patients has significant morbidity, poorer quality of life, and substantial economic costs. TOL, defined as graft acceptance without functional impairment in the absence of IS, has been achieved in some pediatric LT recipients. Using mass cytometry, peripheral blood immunotyping was performed to characterize differences between tolerant patients and patients who are stable on single-agent IS. Single-cell mass cytometry was performed using blood samples from a single-center pediatric LT population of operationally tolerant patients to comprehensively characterize the immune cell populations in the tolerant state compared with patients on chronic low-dose IS. Specific T-cell populations of interest were confirmed by flow cytometry. This high-dimensional phenotypic analysis revealed distinct immunoprofiles between transplant populations as well as a CD4⁺ TOT (CD4⁺ CD5⁺ CD25⁺ CD38^-/lo CD45RA) that correlates with tolerance in pediatric LT recipients. In TOL patients, the TOT was significantly increased as compared to patients stable on low levels of IS. This TOT cell was confirmed by flow cytometry and is distinct from classic Treg cells. These results demonstrate the power of mass cytometry to discover significant immune cell signatures that have diagnostic potential.

Living donor liver transplantation for inborn errors of metabolism - An underutilized resource in the United States

Inborn metabolic diseases of the liver can be life-threatening disorders that cause debilitating and permanent neurological damage. Symptoms may manifest as early as the neonatal period. Liver transplant replaces the enzymatically deficient liver, allowing for metabolism of toxic metabolites. LDLT for metabolic disorders is rarely performed in the United States as compared to countries such as Japan, where they report >2000 cases performed within the past two decades. Patient and graft survival is comparable to that of the United States, where most of the studies are based on deceased donors. No living donor complications were observed, suggesting that LDLT is as safe and effective as deceased donor transplants performed in the USA. Increased utilization of living donors in the USA will allow for early transplantation to prevent permanent neurological damage in those with severe disease. Pediatric transplant centers should consider utilizing living donors when feasible for children with metabolic disorders of the liver.

Effect of Liver Transplant on Long-term Disease-Free Survival in Children With Hepatoblastoma and Hepatocellular Cancer

INTRODUCTION

Hepatoblastoma (HBL) and hepatocellular cancer (HCC) are the most common primary hepatic malignant neoplasms in childhood. Given the rarity of these childhood tumors and their propensity to present at advanced stages, updated long-term data are needed.

OBJECTIVE

To determine the efficacy of liver transplant in children with HBL or HCC.

DESIGN, PARTICIPANTS, AND SETTING

This single-institution retrospective medical record review and analysis spanned from January 1, 1997, through September 17, 2014, at Stanford University School of Medicine. A total of 40 patients younger than 18 years underwent liver transplant for treatment of HBL (n = 30) or HCC (n = 10) during the study period, with follow-up until September 17, 2014. Patients who underwent transplant for HCC included those with tumors that were greater in size than what is proposed by the Milan (a single tumor measuring ≤5 cm or ≤3 nodules measuring ≤3 cm) and University of California, San Francisco (single tumor measuring ≤6.5 cm or ≤3 nodules measuring ≤4.5 cm and a total diameter of ≤8 cm), criteria.

MAIN OUTCOMES AND MEASURES

Disease-free and overall patient survival and graft survival.

RESULTS

Using a Kaplan-Meier survival analysis, 1-, 5-, and 10-year disease-free survival after liver transplant was 93%, 82%, and 82%, respectively, for 30 patients with HBL and 90%, 78%, and 78%, respectively, for 10 patients with HCC. Risk factors associated with HBL recurrence after transplant included having pretreatment extent of disease stage IV lesions and a longer waiting list time and being older at the time of the transplant. Recurrence was found in 2 of 7 patients with HBL and pretransplant metastases, which were not found to be an independent risk factor for recurrence. Patients with HCC larger than the proposed Milan and University of California, San Francisco, criteria experienced good 5-year disease-free (82%) and overall (78%) survival after transplant. Being older at the time of transplant (18 vs 11 years; P = .04) and the presence of metastatic disease (1 patient vs none; P = .05) were associated with HCC tumor recurrence.

CONCLUSIONS AND RELEVANCE

Liver transplant combined with chemotherapy is an excellent treatment that provides long-term disease-free survival in children diagnosed with advanced HBL and HCC. Early addition to a waiting list and aggressive multimodal therapy provide excellent results. Transplant should still be considered in children with HCC larger than the Milan and University of California, San Francisco, criteria.

Epstein-Barr virus modulates host cell microRNA-194 to promote IL-10 production and B lymphoma cell survival

Epstein-Barr virus (EBV) is a γ-herpesvirus that is linked to the development of posttransplant lymphoproliferative disorder (PTLD) in solid organ recipients. We previously demonstrated that EBV(+) B cell lymphoma cell lines isolated from patients with PTLD produce human IL-10 as an autocrine growth factor. However, little is known regarding IL-10 regulation in B cells. Here we show that EBV infection markedly alters the expression of host B cell microRNA, a class of small noncoding RNA that is an important regulator of transcriptional and posttranscriptional gene expression. Gene arrays reveal unique microRNA profiles in EBV(+) B cell lymphoma lines from patients with PTLD, compared to normal B cells or in vitro generated EBV(+) lymphoblastoid cell lines. We show that microRNA-194 expression is uniquely suppressed in EBV(+) B cell lines from PTLD patients and that the 3'untranslated region of IL-10 is targeted by microRNA-194. Overexpression of microRNA-194 attenuates IL-10 production and increases apoptosis of EBV(+) B cell lymphoma lines. Together, these data indicate that EBV co-opts the host B cell microRNA network and specifically suppresses microRNA-194 to override control of IL-10 expression. Thus, modulation of microRNA-194 may constitute a novel approach to inhibiting proliferation of EBV(+) B cell lymphomas in PTLD.