Imaging Delay Following Liver-Directed Therapy Increases Progression Risk in Early- to Intermediate-Stage Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related deaths in the world. Patients with early-stage HCC are treated with liver-directed therapies to bridge or downstage for liver transplantation (LT). In this study, the impact of HCC care delay on HCC progression among early-stage patients was investigated. Early-stage HCC patients undergoing their first cycle of liver-directed therapy (LDT) for bridge/downstaging to LT between 04/2016 and 04/2022 were retrospectively analyzed. Baseline variables were analyzed for risk of disease progression and time to progression (TTP). HCC care delay was determined by the number of rescheduled appointments related to HCC care. The study cohort consisted of 316 patients who received first-cycle LDT. The HCC care no-show rate was associated with TTP (p = 0.004), while the overall no-show rate was not (p = 0.242). The HCC care no-show rate and HCC care delay were further expanded as no-show rates and rescheduled appointments for imaging, laboratory, and office visits, respectively. More than 60% of patients experienced HCC care delay for imaging and laboratory appointments compared to just 8% for office visits. Multivariate analysis revealed that HCC-specific no-show rates and HCC care delay for imaging (p < 0.001) were both independently associated with TTP, highlighting the importance of minimizing delays in early-stage HCC imaging surveillance to reduce disease progression risk.

Lineage-specific regulation of PD-1 expression in early-stage hepatocellular carcinoma following 90yttrium transarterial radioembolization - Implications in treatment outcomes.

BACKGROUND: Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related deaths in the world. Liver-directed therapies, including 90Yttrium (90Y) radioembolization, play an integral role in the management of HCC with excellent response rates. This has led to clinical trials of immunotherapy in combination with 90Y. Elevated PD-1 expression and lymphopenia were recently shown as risk factors for disease progression in early-stage HCC treated with liver-directed therapies. The aim of this study was to investigate PD-1 expression dynamics in bridge/downstage to transplant in HCC patients receiving first-cycle 90Y and evaluate the impact of these changes on response rates and time-to-progression (TTP). METHODS: Patients with HCC receiving first-cycle 90Y as a bridge to liver transplantation (n = 99) were prospectively enrolled. Blood specimens were collected before 90Y and again during routine imagining follow-up to analyze PD-1 expression via flow cytometry. Complete and objective response rates (CR and ORR) were determined using mRECIST. RESULTS: In 84/88 patients with available follow-up imaging, 83% had a localized ORR with 63% having localized CR. For overall response, 71% and 54% experienced ORR and CR, respectively. Post-90Y PD-1 upregulation in CD8 + associated with HCC progression and decreased TTP. Treatment with 90Y was associated with an anticipated significant post-treatment drop in lymphocytes (P < 0.001) that was independent of PD-1 expression for either CD4+ or CD8+ T cells (P = 0.751 and P = 0.375) and not associated with TTP risk. The change in lymphocytes was not correlated with PD-1 expression following treatment nor TTP. CONCLUSIONS: Elevated PD-1 expression on peripheral T cells is associated with increased risk of HCC progression and shorter time to progression in bridging/downstaging to transplant HCC patients undergoing first-cycle 90Y. Treatment-induced lymphopenia was not associated with treatment response, or increased progression risk, suggesting this anticipated adverse event does not impact short-term HCC outcomes.

Impaired Autophagy Response in Hepatocellular Carcinomas Enriches Glypican-3 in Exosomes, Not in the Microvesicles.

Background and Aim: HCC development in liver cirrhosis is associated with impaired autophagy leading to increased production of extracellular vesicles (EVs) including exosomes and microvesicles. The goal of the study is to determine which of these particles is primarily involved in releasing of HCC-specific biomarker glypican-3 (GPC3) when autophagy is impaired. Methods: Streptavidin-coated magnetic beads were coupled with either biotinylated CD63 or Annexin A1 antibodies. Coupled beads were incubated with EVs isolated from either HCC culture or serum. EVs captured by immuno-magnetic beads were then stained with FITC or PE fluorescent-conjugated antibodies targeting exosomes (CD81), and microvesicles (ARF6). The percentage of GPC3 enrichment in the microvesicles and exosomes was quantified by flow cytometry. The impact of autophagy modulation on GPC3 enrichment in exosomes and microvesicles was assessed by treating cells with Torin 1 and Bafilomycin A1. For clinical validation, GPC3 content was quantified in microvesicles, and exosomes were isolated from the serum of patients with a recent HCC diagnosis. Results: The immune-magnetic bead assay distinguishes membrane-derived microvesicles from endosome-derived exosomes. The GPC3 expression was only seen in the CD63 beads group but not in the Annexin A1 beads group, confirming that in HCC, GPC3 is preferentially released through exosomes. Furthermore, we found that autophagy induction by Torin1 decreased GPC3-positive exosome secretion and decreased microvesicle release. Conversely, autophagy inhibition by Bafilomycin A1 increased the secretion of GPC3-positive exosomes. Serum analysis showed CD81+ve EVs were detected in exosomes and ARF6+ve vesicles were detected in microvesicles, suggesting that immunoaffinity assay is specific. The exosomal GPC3 enrichment was confirmed in isolated EVs from the serum of patients with HCC. The frequency of GPC3-positive exosomes was higher in patients with HCC (12.4%) compared to exosomes isolated from non-cirrhotic and healthy controls (3.7% and 1.3% respectively, p<0.001). Conclusion: Our results show that GPC3 is enriched in the endolysosomal compartment and released in exosome fractions when autophagy is impaired.

Distinct Gene Expression Profiles in Viable Hepatocellular Carcinoma Treated With Liver-Directed Therapy.

Background: Hepatocellular carcinoma is a heterogeneous tumor that accumulates a mutational burden and dysregulated signaling pathways that differ from early to advanced stages. Liver transplant candidates with early-stage hepatocellular carcinoma (HCC) undergo liver-directed therapy (LDT) to delay disease progression and serve as a bridge to liver transplantation (LT). Unfortunately, >80% of LDT-treated patients have viable HCC in the explant liver, dramatically increasing recurrence risk. Understanding the effect of LDT on early-stage HCC could help identify therapeutic targets to promote complete pathologic necrosis and improve recurrence-free survival. In this study, transcriptomic data from viable HCC in LDT-treated bridged to transplant patients were investigated to understand how treatment may affect tumor signaling pathways. Methods: Multiplex transcriptomic gene analysis was performed with mRNA extracted from viable tumors of HCC patients bridged to transplant using LDT. The NanoString nCounter® Tumor Signaling 360 panel was used that contained 780 genes from 48 pathways involved in tumor biology within the microenvironment as well as antitumoral immune responses. Results: Hierarchical clustering separated tumors into three subtypes (HCC-1, HCC-2, and HCC-3) each with distinct differences in anti-tumoral signaling and immune infiltration within the tumor microenvironment. Immune infiltration (neutrophils, T cells, and macrophages) were all lowest in subtype HCC-3. The tumor inflammatory signature consisting of 18 genes associated with PD-1/PD-L1 inhibition, antigen presentation, chemokine secretion, and adaptive immune responses was highest in subtype HCC-1 and lowest in HCC-3. History of decompensation and etiology were associated with HCC subtype favoring downregulations in inflammation and immune infiltration with upregulation of lipid metabolism. Gene expression among intrahepatic lesions was remarkably similar with >85% of genes expressed in both lesions. Genes differentially expressed (<8 genes per patient) in multifocal disease were all upregulated in LDT-treated tumors from pathways involving epithelial mesenchymal transition, extracellular matrix remodeling, and/or inflammation potentially implicating intrahepatic metastases. Conclusion: Incomplete response to LDT may drive expression patterns that inhibit an effective anti-tumoral response through immune exclusion and induce intrahepatic spread.

Hypoalbuminemia Is a Hepatocellular Carcinoma Independent Risk Factor for Tumor Progression in Low-Risk Bridge to Transplant Candidates.

Due to active hepatocellular carcinoma (HCC) surveillance, many patients are diagnosed with early-stage disease and are usually amendable to curative treatments. These patients lack poor prognostic factors associated with Milan Criteria and alpha fetoprotein (AFP) biomarker levels. There are currently limited strategies to assess prognosis in the patients who remain at risk of post-treatment HCC progression. In a cohort of liver transplant (LT) candidates with HCC, this study seeks to identify factors prior to liver-directed therapy (LDT) associated with time to progression (TTP). This is a retrospective analysis of prospectively collected data from LT candidates with recently diagnosed HCC and receiving LDT as a bridge to LT at three interventional oncology programs within a single system (n = 373). Demographics, clinical hepatology and serology, and factors related to HCC burden were extracted and analyzed for associations with TTP risk. Albumin level below the cohort median (3.4 g/dL) emerged as an independent risk factor for TTP controlling for AFP > 20 ng/mL as well as Milan, T-stage, and Barcelona Clinic Liver Cancer (BCLC) stage individually. In modality-specific subgroup survival analysis, albumin-based TTP stratification was restricted to patients receiving first cycle microwave ablation (p = 0.007). In n = 162 patients matching all low-risk criteria for Milan, T-stage, BCLC stage, and AFP, the effect of albumin < 3.4 g/dL remained significant for TTP (p = 0.004) with 2-year TTP rates of 68% (<3.4 g/dL) compared to 95% (≥3.4 g/dL). In optimal bridge to LT candidates with small HCC and low AFP biomarker levels, albumin level at treatment baseline provides an HCC-independent positive prognostic factor for risk of HCC progression prior to LT.

PD-1 expression in hepatocellular carcinoma predicts liver-directed therapy response and bridge-to-transplant survival.

BACKGROUND: Hepatocellular carcinoma (HCC) patients undergo liver-directed therapy (LDT) to control tumor burden while awaiting liver transplantation with response impacting waitlist survival. In this study, we investigate the link between absolute lymphocyte count (ALC) and PD-1 expression with response to LDT and bridge-to-transplant survival. METHODS: Treatment-naïve HCC patients (n = 86) undergoing LDT were enrolled at a single center from August 2016-March 2020. Response to LDT was determined using mRECIST. Blood samples were collected on the day of LDT and at follow-up. Cells were analyzed for phenotype by flow cytometry. Outcomes were liver transplantation or tumor progression. RESULTS: Incomplete response to initial LDT was associated with tumor progression precluding liver transplantation (OR: 7.6, 1.7 - 33.3, P < 0.001). Univariate analysis of baseline T cell phenotypes revealed ALC (OR: 0.44, 0.24-0.85, P = 0.009) as well as intermediate expression of PD-1 on CD4 (OR: 3.3, 1.03-10.3, P = 0.034) and CD8 T cells (OR: 3.0, 0.99-8.8 P = 0.043) associated with incomplete response to LDT. Elevations in PD-1 expression were associated with increased risk of bridge-to-transplant tumor progression (HR: 3.2, 1.2-9.4). In patients successfully bridged to liver transplantation, pre-treatment peripheral PD-1 profile was associated with advanced tumor staging (P < 0.005) with 2/4 of patients with elevations in PD-1 having T3-T4 TNM staging compared to 0 with low PD-1 expression. CONCLUSION: Low lymphocyte count or elevated expression of the PD-1 checkpoint inhibitor is associated with incomplete response to LDT and increased risk of bridge-to-transplant tumor progression. Patients with impaired T cell homeostasis may benefit from PD-1 immunotherapy to improve response to LDT and improve bridge-to-transplant outcomes.

Baseline Alpha-Fetoprotein, Alpha-Fetoprotein-L3, and Des-Gamma-Carboxy Prothrombin Biomarker Status in Bridge to Liver Transplant Outcomes for Hepatocellular Carcinoma.

The biomarkers α-fetoprotein (AFP), Lens culinaris agglutinin-reactive AFP fraction (AFP-L3), and des-γ-carboxy prothrombin (DCP) have emerging implications in hepatocellular carcinoma (HCC) surveillance, overall prognosis, and post-surgical recurrence risk. This retrospective study investigated treatment and bridge to liver transplant (LT) prognosis associated with AFP, AFP-L3%, and DCP biomarker profiles prior to liver-directed therapy (LDT). In a 140-patient cohort, each biomarker was associated with HCC progression risk using the established thresholds of AFP > 20 ng/mL, AFP-L3 > 15%, and DCP > 7.5 ng/mL. Over 60% of the cohort expressed at least one biomarker at baseline. Although most biomarker-positive patients expressed the clinical standard AFP (57/87), only 32% were positive for AFP alone. Biomarker accumulation increased HCC progression risk but was not associated with demographic factors or preserved liver function. Biomarker triple negative patients had smaller index HCC (p = 0.003), decreased multifocal burden (p = 0.010), and a higher objective response rate (ORR, 62% compared to 46%, p = 0.011). Expressing all three biomarkers at baseline was associated with dismal first-line ORR (12%) with a median time to progression (TTP) of only 181 days post-LDT. Patients with triple negative status for the HCC biomarkers AFP, AFP-L3%, and DCP have the highest first-line ORR with < 5% HCC progression 1-year post-LDT. Biomarker profiling can establish baseline prognosis for identifying optimal bridge to LT and downstaging to LT candidates with triple negative biomarker status and providing an ideal post-LDT target as a compliment to radiographic response.

Hepatitis C-associated focal proliferative glomerulonephritis in an aviremic recipient of a hepatitis C-positive antibody donor liver.

Shortage of organs for liver transplantation (LT) and the availability of highly efficient pan-genotypic direct-acting antivirals (DAAs) against hepatitis C virus (HCV) have allowed the use of livers from HCV-positive antibody/negative nucleic acid test donors (dHCV Ab+/NAT-) into aviremic HCV recipients over the last few years. We report the case of a patient who received an LT from an HCV Ab+/NAT- donor and, after HCV viremic conversion, developed a nephrotic syndrome due to a focal proliferative glomerulonephritis early after LT. Patient's renal function and proteinuria resolved after successful treatment with DAAs. Renal and hepatic function remain normal over 24 months of follow-up. This case restates the success of LT using livers from dHCV Ab+/NAT- in aviremic recipients in the context of DAAs while illustrating the risk for potential complications associated with the HCV transmission and reinforcing the importance of early initiation of anti-HCV therapy.

Interleukin-33 / Cyclin D1 imbalance in severe liver steatosis predicts susceptibility to ischemia reperfusion injury.

Transplanting donor livers with severe macrosteatosis is associated with increased risk of primary non-function (PNF). The purpose of this study was to identify steatosis-driven biomarkers as a predisposition to severe liver damage and delayed recovery following ischemia reperfusion injury. Wistar rats were fed a methionine- and choline-deficient (MCD) diet for up to three weeks to achieve severe macrosteatosis (>90%). Animals underwent diet withdrawal to control chow and/or underwent ischemia reperfusion and partial hepatectomy injury (I/R-PHx) and reperfused out to 7 days on control chow. For animals with severe macrosteatosis, hepatic levels of IL-33 decreased while Cyclin D1 levels increased in the absence of NF-κB p65 phosphorylation. Animals with high levels of nuclear Cyclin D1 prior to I/R-PHx either did not survive or had persistent macrosteatosis after 7 days on control chow. Survival 7 days after I/R-PHx fell to 57% which correlated with increased Cyclin D1 and decreased liver IL-33 levels. In the absence of I/R-PHx, withdrawing the MCD diet normalized IL-33, Cyclin D1 levels, and I/R-PHx survival back to baseline. In transplanted grafts with macrosteatosis, higher Cyclin D1 mRNA expression was observed. Shifts in Cyclin D1 and IL-33 expression may identify severely macrosteatotic livers with increased failure risk if subjected to I/R injury. Clinical validation of the panel in donor grafts with macrosteatosis revealed increased Cyclin D1 expression corresponding to delayed graft function. This pre-surgical biomarker panel may identify the subset of livers with increased susceptibility to PNF.

Hip and Knee Arthroplasty Outcomes After Abdominal Organ Transplantation.

This case control study retrospectively compares patients who underwent solid organ transplantation and total joint replacement with a control group that only underwent joint replacement. The study compares 42 transplant patients who underwent liver or kidney transplantation and total hip arthroplasty (THA) or total knee arthroplasty (TKA) to a matched group of 42 nontransplant patients who underwent only THA or TKA. The transplant cohort had significantly more complications (18) than the nontransplant cohort (7) (p D .022). Renal transplant patients had 6.75 times higher odds (95% CI, 1.318-34.565) of experiencing a complication compared with liver transplant patients. The average time between transplant and joint replacement was 2 s 4.9 years. Transplant patients undergoing joint arthroplasty at an average of 2 years posttransplant are at higher risk for complications than a matched cohort of patients undergoing only joint arthroplasty, with renal transplant patients being more at risk for complications than liver transplant patients. (Journal of Surgical Orthopaedic Advances 27(2):119-124, 2018).

Assessment of Response to Transcatheter Arterial Chemoembolization with Doxorubicin-eluting Microspheres: Tumor Biology and Hepatocellular Carcinoma Recurrence in a 5-year Transplant Cohort.

Purpose To assess response to transcatheter arterial chemoembolization (TACE) based on immune markers and tumor biology in patients with hepatocellular carcinoma (HCC) who were bridged to liver transplantation, and to produce an optimized pretransplantation model for posttransplantation recurrence risk. Materials and Methods In this institutional review board-approved HIPAA-compliant retrospective analysis, 93 consecutive patients (73 male, 20 female; mean age, 59.6 years; age range, 23-72 years) underwent TACE with doxorubicin-eluting microspheres (DEB) (hereafter, DEB-TACE) and subsequently underwent transplantation over a 5-year period from July 7, 2011, to May 16, 2016. DEB-TACE response was based on modified Response Evaluation Criteria in Solid Tumors. Imaging responses and posttransplantation recurrence were compared with demographics, liver function, basic immune markers, treatment dose, and tumor morphology. Treatment response and recurrence were analyzed with uni- and multivariate statistics, as well as internal validation and propensity score matching of factors known to affect recurrence to assess independent effects of DEB-TACE response on recurrence. Results Low-grade tumors (grade 0, 1, or 2) demonstrated a favorable long-term treatment response in 87% of patients (complete response, 49%; partial response, 38%; stable disease [SD] or local disease progression [DP], 13%) versus 33% of high-grade tumors (grade 3 or 4) (complete response, 0%; partial response, 33%; SD or DP, 67%) (P < .001). Of the 93 patients who underwent treatment, 82 were followed-up after transplantation (mean duration, 757 days). Recurrence occurred in seven (9%) patients (mean time after transplantation, 635 days). Poor response to DEB-TACE (SD or DP) was present in 86% of cases and accounted for 35% of all patients with SD or DP (P < .001). By using only variables routinely available prior to liver transplantation, a validated model of posttransplantation recurrence risk was produced with a concordance statistic of 0.83. The validated model shows sensitivity of 83.6%, specificity of 82.6%, and negative predictive value of 98.4%, which are pessimistic estimates. Conclusion Response to DEB-TACE is correlated with tumor biology and patients at risk for posttransplantation recurrence, and it may be associated with HCC recurrence after liver transplantation. © RSNA, 2017 Online supplemental material is available for this article.

Predictive model and risk factors associated with a revised definition of early allograft dysfunction in liver transplant recipients.

INTRODUCTION: Early allograft dysfunction (EAD) is a well-defined clinical syndrome that reflects overall graft function within the first week after transplant. The aim of this study was to further refine the definition for EAD. METHOD: In this study, 1124 patients were included for analysis. Logistic regression was performed to identify markers of liver injury associated with 6-month patient and graft failure. RESULTS: Recursive partitioning identified cut-points for ALT/AST > 3000/6000 IU/dL observed within first week, with bilirubin ≥ 10 mg/dL and INR ≥ 1.6 on postoperative day 7 for the revised EAD model. The incidence of updated EAD was 15% (164/1124). Multivariable analysis identified eight risk factors associated with EAD: % macrosteatosis, donor location, donor weight, nonheart beating donors, type of organ transplanted, recipient-associated hepatocellular carcinoma, severity of postreperfusion syndrome, and the amount of transfused fresh frozen plasma. In the presence of EAD, the incidence of post-transplant renal replacement therapy and dialysis dependence increases. There was a significant association of the presence of EAD with 6-month mortality (12% vs 3%) and 6-month graft failure (8% vs 1%). CONCLUSION: Higher AST/ALT level needed as cutoff in comparison with the old EAD definition.

Long-Term Cardiac Morbidity and Mortality in Patients With Aortic Valve Disease Following Liver Transplantation: A Case Matching Study.

INTRODUCTION: This retrospective study examined the role of aortic valve (AV) disease in patients who underwent orthotopic liver transplantation (OLT) to determine the incidence of postoperative cardiac morbidity and mortality when compared with a matched control group without AV disease. METHODS: Patients were included in the AV group if diagnosed with aortic stenosis (AS) or aortic regurgitation or had received AV replacement prior to OLT. The AV group (n = 53) was matched to a control group (n = 212) with the following preoperative variables: type of organ transplanted, age, gender, race, body mass index, MELD, redo-transplantation, preoperative renal replacement therapy, nonalcoholic steatohepatitis, viral hepatitis, diabetes, and coronary artery disease. A 1:4 ratio was utilized to improve the efficiency and power of the analysis. RESULTS: No significant difference in survival or posttransplant cardiac complications (acute coronary syndrome, heart failure, or dysrhythmia) was observed between groups. However, statistically significantly more patients-11% (6/53)-required coronary intervention following OLT in the AV group, whereas 3% (7/212) required coronary intervention (χ2 = 5.8; P = .0156) in the control group. Following OLT, 9% (5/53) in the AV group required surgical or nonsurgical AV intervention, whereas no valvular events were observed in the control group. Event-free survival in the AV group, with an end point defined as AV intervention (n = 5) and death (n = 10), was 92% (49/53) at 1 year, 83% (44/53) at 3 years, and 72% (38/53) at 5 years. CONCLUSIONS: Patients with pretransplant AV replacement or AS have significant cardiac complications (myocardial infarction, AV replacement, or cardiac death) in 1 to 3 years post-OLT.

Post-Liver Transplant Delirium Increases Mortality and Length of Stay.

BACKGROUND: Incidence of delirium after liver transplantation (LT) has been reported to occur in 10%-47% of patients and is associated with increased hospital and intensive care unit lengths of stay and poor outcomes. METHODS: Our primary objective was to evaluate the incidence and predisposing risk factors for developing delirium after LT. Our secondary objectives were to describe how delirium is managed in patients after LT, to examine the utilization of resources associated with delirium after LT, and to analyze the outcomes of patients who were treated for delirium after LT. RESULTS: In a population of 181 consecutive patients who received an LT, 38 (21.0%) developed delirium. In the multivariate analysis, delirium was associated with pretransplant use of antidepressants (odds ratio [OR] 3.34, 95% confidence interval [CI] 1.29-8.70) and pretransplant hospital admission for encephalopathy (OR 4.39, 95% CI 1.77-10.9). Patients with delirium spent more time on mechanical ventilation (2.0 vs 1.3 days, P=0.008) and had longer intensive care unit stays (4.6 vs 2.7 days, P=0.008), longer hospital stays (27.6 vs 11.2 days, P=0.003), and higher 6-month mortality (13.2% vs 1.4%, P=0.003) than patients who did not develop delirium. CONCLUSION: The presence of delirium is common after LT and is associated with high morbidity and mortality within the first 6 months posttransplant. Pretransplant factors independently associated with developing delirium after LT include prior use of antidepressants and pretransplant hospital admission for encephalopathy. Efforts should be made to identify patients at risk for delirium, as protocol-based management may improve outcomes in a cost-effective manner.

Negligible Oval Cell Proliferation Following Ischemia-Reperfusion Injury With and Without Partial Hepatectomy.

BACKGROUND: Hepatic oval cells proliferate to replace hepatocytes and restore liver function when hepatocyte proliferation is compromised or inadequate. Exposure to chemical carcinogens, severe liver steatosis, and partial hepatectomy has been used in animal models to demonstrate the role of oval cells in liver regeneration. Ischemia-reperfusion injury (IRI) causes hepatocellular damage and death in the absence of confounding chemical toxicity; however, oval cell induction by IRI has not been demonstrated in vivo. We examine oval cell induction following partial IRI. METHODS: Wistar rats were subjected to 2 IRI protocols: 70% warm liver ischemia for 30 minutes followed by reperfusion or 70% warm liver ischemia for 30 minutes with partial hepatectomy of the nonischemic lobes followed by reperfusion. Liver injury was monitored by serum alanine aminotransferase (ALT) at 1 day and 7 days of reperfusion. Oval cell proliferation was monitored by indirect immunofluorescence staining using the surface markers BD.2 and Thy-1. Cellular proliferation was quantified by 5-ethynyl-2'-deoxyuridine (EdU) incorporation in vivo. RESULTS: Serum ALT elevation was only observed at the 1-day time point in the IRI with partial hepatectomy model. Oval cell marker expression was restricted to the biliary structures in both the ischemic and the nonischemic control lobes. Oval cell induction, measured by changes in the frequency of BD.2 and Thy-1 expression and EdU incorporation, was not significantly altered by IRI. CONCLUSION: In both mild and moderate IRI models, we did not find evidence of oval cell induction or proliferation. EdU staining was restricted to hepatocytes, suggesting that liver regeneration following IRI is mediated by hepatocyte proliferation.

Novel Biliary Reconstruction Techniques During Liver Transplantation.

BACKGROUND: Biliary complications remain a significant problem following liver transplantation. Several surgical options can be used to deal with a significant size mismatch between the donor and recipient bile ducts during the biliary anastomosis. We compared biliary transposition to recipient biliary ductoplasty in cadaveric liver transplant. METHODS: A total of 33 reconstructions were performed from January 1, 2005 to December 31, 2013. In the biliary transposition group (n=23), 5 reconstructions were performed using an internal stent (5 or 8 French pediatric feeding tube), and 18 were performed without. Of the 10 biliary ductoplasties, 2 were performed with a stent. All patients were managed with standard immunosuppression and ursodiol. Follow-up ranged from 2 months to 5 years. RESULTS: No patients in the biliary transposition group required reoperation; 1 patient had an internal stent removed for recurrent unexplained leukocytosis, and 2 patients required endoscopic retrograde cholangiography and stent placement for evidence of stricture. Three anastomotic leaks occurred in the biliary ductoplasty group, and 2 patients in the biliary ductoplasty group required reoperation for biliary complications. CONCLUSION: Our results indicate that biliary reconstruction can be performed with either biliary transposition or biliary ductoplasty. These techniques are particularly useful when a significant mismatch in diameter exists between the donor and recipient bile ducts.

Antibody-Mediated Rejection: A Review.

BACKGROUND: Chronic antibody injury is a serious threat to allograft outcomes and is therefore the center of active research. In the continuum of allograft rejection, the development of antibodies plays a critical role. In recent years, an increased recognition of molecular and histologic changes has provided a better understanding of antibody-mediated rejection (AMR), as well as potential therapeutic interventions. However, several pathways are still unknown, which accounts for the lack of efficacy of some of the currently available agents that are used to treat rejection. METHODS: We review the current diagnostic criteria for AMR; AMR paradigms; and desensitization, treatment, and prevention strategies. RESULTS: Chronic antibody-mediated endothelial injury results in transplant glomerulopathy, manifested as glomerular basement membrane duplication, double contouring, or splitting. Clinical manifestations of AMR include proteinuria and a rise in serum creatinine. Current strategies for the treatment of AMR include antibody depletion with plasmapheresis (PLEX), immunoadsorption (IA), immunomodulation with intravenous immunoglobulin (IVIG), and T cell- or B cell-depleting agents. Some treatment benefits have been found in using PLEX and IA, and some small nonrandomized trials have identified some benefits in using rituximab and the proteasome inhibitor-based therapy bortezomib. More recent histologic follow-ups of patients treated with bortezomib have not shown significant benefits in terms of allograft outcomes. Furthermore, no specific treatment approaches have been approved by the US Food and Drug Administration. Other agents used for more difficult rejections include bortezomib and eculizumab (an anti-C5 monoclonal antibody). CONCLUSION: AMR is a fascinating field with ample opportunities for research and progress in the future. Despite the use of advanced techniques for the detection of human leukocyte antigen (HLA) or non-HLA donor-specific antibodies, alloimmune response remains an important barrier for successful long-term allograft function. Treatment of AMR with currently available therapies has produced a variety of results, some of them suboptimal, precluding the development of standardized protocols. New therapies are promising, but randomized controlled trials are needed to find surrogate markers and improve the efficacy of therapy.

Cyclin D1 in the Liver: Role of Noncanonical Signaling in Liver Steatosis and Hormone Regulation.

BACKGROUND: Cyclin D1 is an important protein for cell cycle progression; however, functions independent of the cell cycle have been described in the liver. Cyclin D1 is also involved in DNA repair, is overexpressed in many cancers, and functions as a proto-oncogene. The lesser-known roles of Cyclin D1, specifically in hepatocytes, impact liver steatosis and hormone regulation in the liver. METHODS: A comprehensive search of PubMed was conducted using the keywords Cyclin D1, steatosis, lipogenesis, and liver transplantation. In this article, we review the results from this literature search, with a focus on the role of Cyclin D1 in hepatic lipogenesis and gluconeogenesis, as well as the impact and function of this protein in hepatic steatosis. RESULTS: Cyclin D1 represses carbohydrate response element binding protein (ChREBP) and results in a decrease in transcription of fatty acid synthase (FAS) and acetyl-coenzyme A carboxylase (ACC). Cyclin D1 also inhibits peroxisome proliferator-activated receptor gamma (PPARγ) which is involved in hepatic lipogenesis. Cyclin D1 inhibits both hepatocyte nuclear factor 4 alpha (HNF4α) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α) and represses transcription of lipogenic genes FAS and liver-type pyruvate kinase (Pklr), along with the gluconeogenic genes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase). CONCLUSION: Cyclin D1 represses multiple proteins involved in both lipogenesis and gluconeogenesis in the liver. Targeting Cyclin D1 to decrease hepatic steatosis in patients with nonalcoholic fatty liver disease or alcoholic fatty liver disease may help improve patient health and the quality of the donor liver pool.

Balloon-Occlusion Technique for Managing Portal Vein Hemorrhage in Liver Transplantation.

BACKGROUND: Portal vein thrombosis (PVT) is relatively common among candidates for liver transplantation and can present significant intraoperative challenges. Depending on the extent of PVT, thromboendovenectomy (TEV), portal bypass, or systemic inflow may be required to restore portal inflow. While TEV is the most commonly used approach to restore anatomic portal inflow, portal vein injury and life-threatening hemorrhage are risks with this technique. CASE REPORT: We present a salvage technique for managing portal vein injury during TEV using intraluminal balloon occlusion of the portal vein during portal vein repair and reconstruction. This alternative mode of bleeding control optimizes exposure to the retropancreatic space and avoids direct application of vascular clamps that can cause further injury to the vessel and surrounding tissue. CONCLUSION: Careful preoperative planning and anticipation of potential problems are essential for safe and effective management of complex PVT intraoperatively. The balloon-occlusion technique can facilitate safe and efficient repair of a portal vein injury during TEV for liver transplantation.

Interpreting Outcomes in DCDD Liver Transplantation: First Report of the Multicenter IDOL Consortium.

BACKGROUND: In the United States, 5% of adult liver transplant recipients receive a graft donation after circulatory determination of death (DCDD). Concerns for ischemic cholangiopathy (IC), a disease of diffuse intrahepatic stricturing limits broader DCDD use. Single-center reports demonstrate large variation in outcomes. METHODS: Retrospective deidentified data collected between 2005 and 2013 were entered electronically by 10 centers via a Research Electronic Data Capture database. Our primary outcome was development of intrahepatic biliary strictures consistent with IC. RESULTS: Within 6 months post-DCDD transplant, 162 (21.8%) patients developed a biliary stricture, of which 88 (11.8%) exhibited intrahepatic structuring consistent with IC. Unadjusted 6-month IC rate among the 10 centers varied significantly (P = 0.006) from 6.3% to 25.9%. The only factor associated with increased risk of IC within 6 months was Roux-en-Y hepaticojejunostomy (vs duct-to-duct) (odds ratio, 3.06; 95% confidence interval, 1.52-6.16; P = 0.002). Graft failure by 6 months was more than 3 times higher for DCDD recipients with IC (odds ratio for IC, 3.36; 95% confidence interval, 1.95-5.79). CONCLUSIONS: This first report of the large combined experience with DCDD from the Improving DCDD Outcomes in Liver Transplant consortium demonstrates significant differences in IC among centers, the importance of biliary strictures as a risk factor for graft failure, and does not validate other risk factors for IC found in smaller studies.