Liver transplantation for advanced hepatocellular carcinoma

Safety and Therapeutic Outcomes of Adjuvant Immunotherapy With Autologous Cytokine-induced Killer Cells for Patients With Hepatocellular Carcinoma Beyond Milan Criteria After Liver Transplantation

BACKGROUND

Adjuvant immunotherapy with autologous cytokine-induced killer (CIK) cells for hepatocellular carcinoma (HCC) remains understudied in liver transplant patients because of potential risks of acute rejection and diminished efficacy by immunosuppression.

METHODS

This study examined the safety and effectiveness of CIK therapy in patients with HCC exceeding the Milan criteria, treated at 2 Korean hospitals between 2019 and 2021. We analyzed clinical outcomes of 16 patients who underwent CIK therapy compared with 44 propensity-matched controls who did not receive CIK therapy. CIK cells were administered in 6 escalating doses, either 3 or 6 times over the course of weeks 4, 5, 6, 8, 10, and 12 posttransplantation.

RESULTS

CIK therapy was well-tolerated without significant treatment-related adverse reactions. Maximal tolerated dose of CIK cells was 10 × 109, which had been repeated 6 times. The CIK group exhibited higher 2-y HCC recurrence-free (87.5% versus 62.9%, P = 0.027) and patient survival (100% versus 81.5%, P = 0.002) rates, with no significant difference in rejection-free survival rates (92.9% versus 95.0%, P = 0.926) compared with the no-CIK group. Subgroup analysis showed that the CIK group in patients with high retreat scores, elevated R3-α-fetoprotein scores, and those beyond the University of California San Francisco criteria had improved HCC recurrence-free survival. Immunological evaluation showed elevated CD8+ T cells and polymorphonuclear myeloid-derived suppressor cells with transient increases in granzyme B and tumor necrosis factor-α levels in the CIK group.

CONCLUSIONS

These findings advocate CIK therapy as a safe and effective, potential adjuvant treatment for HCC beyond Milan criteria after transplantation, supporting further validation trials.

Small graft size and hepatocellular carcinoma outcomes in living donor liver transplantation: a retrospective multicentric cohort study

INTRODUCTION

This study examined associations between the graft-to-recipient weight ratio (GRWR) for adult-to-adult living donor liver transplantation (LDLT) and hepatocellular carcinoma (HCC) outcomes.

MATERIALS AND METHODS

Data from patients in the Korean Organ Transplantation Registry who underwent LDLT for HCC from 2014 to 2021 were retrospectively reviewed. Patients were categorized using the cutoff GRWR for HCC recurrence determined by an adjusted cubic spline (GRWR <0.7% vs. GRWR ≥0.7%). Recurrence-free survival (RFS) and HCC recurrence were analyzed in the entire and a 1:5 propensity-matched cohort.

RESULTS

The eligible cohort consisted of 2005 LDLT recipients [GRWR <0.7 ( n =59) vs. GRWR ≥0.7 ( n =1946)]. In the entire cohort, 5-year RFS was significantly lower in the GRWR <0.7 than in the GRWR ≥0.7 group (66.7% vs. 76.7%, P =0.019), although HCC recurrence was not different between groups (77.1% vs. 80.7%, P =0.234). This trend was similar in the matched cohort ( P =0.014 for RFS and P =0.096 for HCC recurrence). In multivariable analyses, GRWR <0.7 was an independent risk factor for RFS [adjusted hazard ratio (aHR) 1.89, P =0.012], but the result was marginal for HCC recurrence (aHR 1.61, P =0.066). In the pretransplant tumor burden subgroup analysis, GRWR <0.7 was a significant risk factor for both RFS and HCC recurrence only for tumors exceeding the Milan criteria (aHR 3.10, P <0.001 for RFS; aHR 2.92, P =0.003 for HCC recurrence) or with MoRAL scores in the fourth quartile (aHR 3.33, P <0.001 for RFS; aHR 2.61, P =0.019 for HCC recurrence).

CONCLUSIONS

A GRWR <0.7 potentially leads to lower RFS and higher HCC recurrence after LDLT when the pretransplant tumor burden is high.

Preoperative assessment of microvascular invasion risk using gadoxetate-enhanced MRI for predicting outcomes after liver transplantation for single hepatocellular carcinoma within the Milan criteria

OBJECTIVE

To compare therapeutic outcomes after liver transplantation (LT) between hepatocellular carcinomas (HCC) with low and high risk for microvascular invasion (MVI) within the Milan criteria evaluated preoperatively.

METHODS

Eighty patients with a single HCC who underwent LT as the initial therapy between 2008 and 2017 were included from two tertiary referral medical centers in a HBV-predominant population. A preoperative MVI-risk model was used to identify low- and high-risk patients. Recurrence-free survival (RFS) after LT between the two risk groups was compared using Kaplan-Meier curves with the log-rank test. Prognostic factors for RFS were identified using a multivariable Cox hazard regression analysis.

RESULTS

Eighty patients were included (mean age, 51.8 years +/- 7.5 [standard deviation], 65 men). Patients were divided into low-risk (n = 64) and high-risk (n = 16) groups for MVI. The RFS rates after LT were significantly lower in the MVI high-risk group compared to the low-risk group at 1 year (75.0% [95% CI: 56.5-99.5%] vs. 96.9% [92.7-100%], p = 0.048), 3 years (62.5% [42.8-91.4%] vs. 95.3% [90.3-100%], p = 0.008), and 5 years (62.5% [42.8-91.4%] vs. and 95.3% [90.3-100%], p = 0.008). In addition, multivariable analysis showed that MVI high risk was the only significant factor for poor RFS (p = 0.016).

CONCLUSION

HCC patients with a high risk of MVI showed significantly lower RFS after LT than those without. This model could aid in selecting optimal candidates in addition to the Milan criteria when considering upfront LT for patients with HCC if alternative treatment options are available.

CLINICAL RELEVANCE STATEMENT

High risk for microvascular invasion (MVI) in hepatocellular carcinoma patients lowered recurrence-free survival after liver transplantation, despite meeting the Milan criteria. Identifying MVI risk could aid candidate selection for upfront liver transplantation, particularly if alternative treatments are available.

KEY POINTS

• A predictive model-derived microvascular invasion (MVI) high- and low-risk groups had a significant difference in the incidence of MVI on pathology. • Recurrence-free survival after liver transplantation (LT) for single hepatocellular carcinoma (HCC) within the Milan criteria was significantly different between the MVI high- and low-risk groups. • The peak incidence of tumor recurrence was 20 months after liver transplantation, probably indicating that HCC with high risk for MVI had a high risk of early (≤ 2 years) tumor recurrence.

Anticancer Effect of Statins in Patients Undergoing Liver Transplantation for Hepatocellular Carcinoma

The anticancer effect of statins is drawing attention. However, it is unclear whether statin use reduces the risk of hepatocellular carcinoma (HCC) recurrence in patients who undergo liver transplantation (LT) for HCC. Consecutive patients who underwent LT for HCC between 1995 and 2019 were enrolled. The effects of statins on HCC recurrence and mortality were compared between statin user and statin nonuser groups. We performed the analyses in a variety of ways, including inverse probability treatment weighting (IPTW) methods to balance any confounders and the landmark method to avoid immortal time bias. A total of 430 patients were enrolled, among whom 323 (75.1%) were statin nonusers and 107 (24.9%) were statin users. During a median of 64.9 months (IQR, 26.1-122.6 months) of follow-up, 79 patients (18.4%) had HCC recurrence and 111 (25.8%) died. Among those who died, 53 (47.7%) were identified as HCC-related mortalities. Statin use was a predictor of HCC recurrence (adjusted hazard ratio [HR], 0.3; 95% confidence interval [CI], 0.1-0.6; P = 0.002), all-cause mortality (adjusted HR, 0.3; 95% CI, 0.2-0.5; P < 0.001), and HCC-related mortality (adjusted HR, 0.4; 95% CI, 0.2-0.9; P = 0.03). The effects of statin use on clinical outcomes were also identified through IPTW analysis. There was a dose-dependent relationship between statin use and HCC recurrence. The anticancer effect of statins on HCC recurrence was consistently significant across multivariable-stratified and sensitivity analyses. Statin use significantly reduced the risk of HCC recurrence and improved the survival of patients who underwent LT for HCC.

Bromodomain-containing protein BRPF1 is a therapeutic target for liver cancer

Epigenetic deregulation plays an essential role in hepatocellular carcinoma (HCC) progression. Bromodomains are epigenetic "readers" of histone acetylation. Recently, bromodomain inhibitors have exhibited promising therapeutic potential for cancer treatment. Using transcriptome sequencing, we identified BRPF1 (bromodomain and PHD finger containing 1) as the most significantly upregulated gene among the 43 bromodomain-containing genes in human HCC. BRPF1 upregulation was significantly associated with poor patient survival. Gene ablation or pharmacological inactivation of BRPF1 significantly attenuated HCC cell growth in vitro and in vivo. BRPF1 was involved in cell cycle progression, senescence and cancer stemness. Transcriptome sequencing revealed that BRPF1 is a master regulator controlling the expression of multiple key oncogenes, including E2F2 and EZH2. We demonstrated that BRPF1 activated E2F2 and EZH2 expression by facilitating promoter H3K14 acetylation through MOZ/MORF complex. In conclusion, BRPF1 is frequently upregulated in human HCCs. Targeting BRPF1 may be an approach for HCC treatment.

Is Macroscopic Portal Vein Tumor Thrombosis of HCC Really an Exclusion for Liver Transplantation?

PURPOSE

Hepatocellular carcinoma is a heterogenous group of disease with a spectrum of disease presentations that developed on the setting of liver cirrhosis, although the achievements made in the imaging techniques have enabled the early diagnosis in nearly 60% of the cases in cirrhotic patients. However, hepatobiliary centers and tertiary liver transplant centers have to treat patients with advanced hepatocellular carcinoma with portal venous tumor thrombosis.

METHODS

In this review, liver transplantation results in hepatocellular carcinoma patients with portal vein tumor thrombosis is reviewed.

RESULTS

Although historically portal venous tumor thrombosis is considered a contraindication for radical surgical procedures such as liver transplantation, current data suggests that patients with hepatocellular carcinoma and macrovascular invasion can achieve favorable outcomes with liver transplantation provided that strict selection criteria is applied. One of the cornerstones of treatment of these patients is development of locoregional therapy such as transarterial chemo and radioembolizations. Transarterial radioembolization is effective in patients if the pretreatment liver failure is mild and the tumor burden including extension to the portal vein is low. Although data is lacking especially radioembolization could even help physicians to differentiate tumors with favorable biologic characteristics.

CONCLUSIONS

Therefore, these patients should be subject of multimodality treatment, and liver transplantation should be offered whenever objective and significant response is obtained by locoregional therapies.

Predicting Hepatocellular Carcinoma Recurrence Beyond Milan Criteria After Liver Resection for Solitary Hepatocellular Carcinoma

BACKGROUND AND PURPOSE

Several hepatectomy patients with HCC who are initially transplantable (within MC) developed untransplantable HCC recurrence (beyond MC) after primary curative liver resection. The purpose of our study is to identify the risk factors of untransplantable hepatocellular carcinoma (HCC) recurrence after primary curative resection of solitary HCC and solitary HCC within Milan criteria (MC).

METHODS

We retrospectively reviewed 592 patients with recurrent HCC who underwent liver resection due to solitary HCC between 2005 and 2011.

RESULTS

All patients were Child-Pugh class A. At primary curative hepatectomy, 411 patients (69.4%) were diagnosed with HCC within MC and 181 patients (30.6%) had HCC beyond MC. The mean time from primary hepatectomy to recurrence was 14 months (range, 1-116 months). At HCC recurrence, 93 patients (15.7%) were diagnosed beyond MC. Multivariate analysis showed that microvascular invasion and a tumor grade of 3 or 4 were closely associated with a high risk of HCC recurrence beyond MC in patients who had hepatectomy for solitary HCC. Of the 411 patients within MC at primary curative hepatectomy, 54 patients (13.9%) developed HCC recurrence beyond MC. Multivariate analysis also showed that microvascular invasion and a tumor grade of 3 or 4 were closely associated with HCC recurrence beyond MC in these patients.

CONCLUSIONS

The present study suggests that the presence of certain unfavorable histological factors in patients who underwent initial liver resection of transplantable HCC within MC with good liver function predicted the development of recurrent HCC beyond MC.

Comparison of Models for Tumor Recurrence after Liver Transplantation for the Patients with Hepatocellular Carcinoma: A Multicenter Long-Term Follow-Up Study

BACKGROUND AND AIMS

Several models have been developed to predict tumor the recurrence of hepatocellular carcinoma (HCC) after liver transplantation besides the conventional Milan criteria (MC), including the MoRAL score. This study aimed to compare the prognostication power of the MoRAL score to most models designed so far in the Eastern and Western countries.

METHODS

This study included 564 patients who underwent living donor liver transplantation (LDLT) in three large-volume hospitals in Korea. The primary and secondary endpoints were time-to-recurrence, and overall survival (OS), respectively. The performance of the MoRAL score was compared with those of other various Liver transplantation (LT) criteria, including the Milan criteria, University of California San Francisco (UCSF) criteria, up-to-seven criteria, Kyoto criteria, AFP model, total tumor volume/AFP criteria, Metroticket 2.0 model, and Weill Cornell Medical College group model.

RESULTS

The median follow-up duration was 78.1 months. Among all models assessed, the MoRAL score showed the best discrimination function for predicting the risk of tumor recurrence after LT, with c-index of 0.78, compared to other models (all p < 0.001). The MoRAL score also represented the best calibration function by Hosmer-Lemeshow test (p = 0.15). Especially in the beyond-MC sub-cohort, the MoRAL score predicted tumor recurrence (c-index, 0.80) and overall survival (OS) (c-index, 0.70) significantly better than any other models (all p < 0.001). When the MoRAL score was low (<314.8), the five-year cumulative risks of tumor recurrence and death were excellent in beyond-MC (27.8%, and 20.5%, respectively) and within-MC (16.3%, and 21.1%, respectively) sub-cohorts.

CONCLUSIONS

The MoRAL score provides the most refined prognostication for predicting HCC recurrence after LDLT.

Multidisciplinary approach is associated with improved survival of hepatocellular carcinoma patients

Background

Given the complexity of managing hepatocellular carcinoma (HCC), a multidisciplinary approach (MDT) is recommended to optimize management of HCC patients. However, evidence suggesting that MDT improves patient outcome is limited.

Methods

We performed a retrospective cohort study of all patients newly-diagnosed with HCC between 2005 and 2013 (n = 6,619). The overall survival (OS) rates between the patients who were and were not managed via MDT were compared in the entire cohort (n = 6,619), and in the exactly matched cohort (n = 1,396).

Results

In the entire cohort, the 5-year survival rate was significantly higher in the patients who were managed via MDT compared to that of the patients who were not (71.2% vs. 49.4%, P < 0.001), with an adjusted hazard ratio (HR) of 0.47 (95% confidence interval [CI]; 0.41–0.53). In the exactly matched cohort, the 5-year survival rate was higher in patients who were managed via MDT (71.4% vs. 58.7%, P < 0.001; HR [95% CI] = 0.67 [0.56–0.80]). The survival benefit of MDT management was observed in most pre-defined subgroups, and was especially significant in patients with poor liver function (ALBI grade 2 or 3), intermediate or advanced tumor stage (BCLC stage B or C), or high alphafetoprotein levels (≥200 ng/ml).

Conclusion

MDT management was associated with improved overall survival in HCC patients, indicating that MDT management can be a valuable option to improve outcome of HCC patients. This warrants prospective evaluations.

Achieving Complete Remission of Hepatocellular Carcinoma: A Significant Predictor for Recurrence-Free Survival after Liver Transplantation

BACKGROUND

Liver transplantation (LT) is a curative treatment for hepatocellular carcinoma (HCC) and the underlying primary liver disease; however, tumor recurrence is still a major issue. Therefore, the aim of this study was to assess predictors and risk factors for HCC recurrence after LT in patients within and outside the Milan criteria with a special focus on the impact of different bridging strategies.

METHODS

All patients who underwent LT for HCC between 07/2002 and 09/2016 at the University Hospital of Muenster were consecutively included in this retrospective study. Database research was performed and a multivariable regression analysis was conducted to explore potential risk factors for HCC recurrence.

RESULTS

A total of 82 patients were eligible for the statistical analysis. Independent of bridging strategy, achieving complete remission (CR) was significantly associated with a lower risk for tumor recurrence (p = 0.029; OR = 0.426, 95% CI 0.198-0.918). A maximal diameter of lesion < 3 cm was also associated with lower recurrence rates (p = 0.040; OR = 0.140, 95% CI 0.022-0.914). Vascular invasion proved to be an independent risk factor for HCC recurrence (p = 0.004; OR = 11.357, 95% CI 2.142-60.199).

CONCLUSION

Achieving CR prior to LT results in a significant risk reduction of HCC recurrence after LT independent of the treatment modalities applied.

Efficacy of Sorafenib for the Treatment of Post-Transplant Hepatocellular Carcinoma Recurrence

BACKGROUND

The role of sorafenib in patients with hepatocellular carcinoma (HCC) recurrence after liver transplantation (LT) has been rarely studied. The aim of this study was to evaluate the efficacy of sorafenib in post-LT era.

METHODS

Consecutive patients with post-transplant HCC recurrence not eligible to resection or locoregional therapy were included. Patients receiving best supportive care (BSC) until 2007 were compared with those treated by sorafenib thereafter.

RESULTS

Of a total of 65 patients, 20 patients received BSC and 45 received sorafenib. Clinical characteristics were similar between two groups except that sorafenib group received tacrolimus and mammalian target-of-rapamycin inhibitors more frequently than BSC group. Treatment with sorafenib conferred a survival advantage as compared with BSC for survival after recurrence (median, 14.2 vs. 6.8 months; P = 0.01). In multivariate analyses, high serum α-fetoprotein level, synchronous intrahepatic recurrence and distant metastasis at the time of recurrence, and BSC were independently associated with poorer survival after recurrence. Sorafenib treatment was associated with better survival after recurrence as compared with BSC (hazard ratio, 0.25; 95% confidence interval, 0.10-0.62; P = 0.002). In addition, sorafenib group showed tolerable toxicity in the post-transplant setting.

CONCLUSION

Sorafenib may be beneficial in patients with post-transplant HCC recurrence.

Nonintegrating Direct Conversion Using mRNA into Hepatocyte-Like Cells

Recently, several researchers have reported that direct reprogramming techniques can be used to differentiate fibroblasts into hepatocyte-like cells without a pluripotent intermediate step. However, the use of viral vectors for conversion continues to pose important challenges in terms of genome integration. Herein, we propose a new method of direct conversion without genome integration with potential clinical applications. To generate hepatocyte-like cells, mRNA coding for the hepatic transcription factors Foxa3 and HNF4α was transfected into mouse embryonic fibroblasts. After 10-12 days, the fibroblasts converted to an epithelial morphology and generated colonies of hepatocyte-like cells (R-iHeps). The generated R-iHeps expressed hepatocyte-specific marker genes and proteins, including albumin, alpha-fetoprotein, HNF4α, CK18, and CYP1A2. To evaluate hepatic function, indocyanine green uptake, periodic acid-Schiff staining, and albumin secretion were assessed. Furthermore, mCherry-positive R-iHeps were engrafted in the liver of Alb-TRECK/SCID mice, and we confirmed FAH enzyme expression in Fah1RTyrc/RJ models. In conclusion, our data suggest that the nonintegrating method using mRNA has potential for cell therapy.

Risk Factors for Dropout From the Liver Transplant Waiting List of Hepatocellular Carcinoma Patients Under Locoregional Treatment

BACKGROUND

In new organ allocation policy, patients with hepatocellular carcinoma (HCC) experience a 6-month delay in being granted Model for End-Stage Liver Disease exception points. However, it may not be fair for patients at risk of early progression of HCC.

METHODS

All patients who were diagnosed as United Network for Organ Sharing (UNOS) stage 1 or 2 of HCC between January 2004 and December 2012 were included. Patients who received surgical resection or liver transplant (LT) as a primary treatment and who did not receive any treatment for HCC were excluded. Patients with baseline Model for End-Stage Liver Disease score ≥22 were also excluded because they have a higher chance of receiving LT. Patients who developed extrahepatic progression within 1 year were considered as high-risk for early recurrence after LT.

RESULTS

A total of 586 patients were included. Mean (SD) age was 59.9 (10.3) years and 409 patients (69.8%) were men. The cumulative incidence of estimated dropout was 8.9% at 6 months; size of the maximum nodule (≥3 cm) and nonachievement of complete response were independent factors. Extrahepatic progression developed in 16 patients (2.7%) within 1 year; size of the maximum nodule (4 cm) and alpha-fetoprotein level (>100 ng/mL) were independent predictors.

CONCLUSIONS

The estimated dropout rate from the waiting list within 6 months was 8.9%. Advantage points might be needed for patients with maximum nodule size ≥3 cm or those with noncomplete response. However, in patients with maximum nodule size ≥4 cm or alpha-fetoprotein level >100 ng/mL, caution is needed.

The Clinical Implications of Liver Resection Margin Size in Patients with Hepatocellular Carcinoma in Terms of Positron Emission Tomography Positivity

BACKGROUND

The positivity of positron emission tomography (PET) in hepatocellular carcinoma (HCC) correlates with aggressive tumor factors and poor survival. Adequate resection margin size is still a topic of debate. We analyzed the clinical implications of resection margin size in patients with HCC in terms of PET positivity.

METHODS

We retrospectively reviewed the medical records of 92 patients who underwent liver resection from March 2012 to October 2015. We investigated prognostic factors for recurrence and survival. We analyzed the correlation of resection margin size and PET positivity. Resection margins were classified as less than 1 cm and more than 1 cm.

RESULTS

Twenty six (31.3%) patients had PET-positive HCC. Multivariate analysis showed PET, satellite nodules, microvessel invasion, and multicentric occurrence were significant prognostic factors for HCC recurrence. Multivariate analysis also showed satellite nodules and microscopic portal vein invasion were significant prognostic factors for overall survival (OS). Resection margin size did not affect disease-free survival (DFS) (p = 0.681) or OS (p = 0.301) in patients with PET-negative HCC, but showed a difference in DFS [<1 cm at 11 months vs. ≥1 cm at 41 months (p = 0.188)] and OS [<1 cm at 28 months vs. ≥1 cm at 48 months (p < 0.001)] in patients with PET-positive HCC.

CONCLUSIONS

PET has low sensitivity for HCC. However, it is useful to predict treatment outcomes after liver resection or liver transplantation for HCC. Although the extent of liver resection must be decided based on liver function, a resection margin size >1 cm may improve DFS and OS in patients with PET-positive HCC.

Hepatobiliary MRI as novel selection criteria in liver transplantation for hepatocellular carcinoma

BACKGROUND & AIMS

Hepatobiliary magnetic resonance imaging (MRI) provides additional information beyond the size and number of tumours, and may have prognostic implications. We examined whether pretransplant radiological features on MRI could be used to stratify the risk of tumour recurrence after liver transplantation (LT) for hepatocellular carcinoma (HCC).

METHODS

A total of 100 patients who had received a liver transplant and who had undergone preoperative gadoxetic acid-enhanced MRI, including the hepatobiliary phase (HBP), were reviewed for tumour size, number, and morphological type (e.g. nodular, nodular with perinodular extension, or confluent multinodular), satellite nodules, non-smooth tumour margins, peritumoural enhancement in arterial phase, peritumoural hypointensity on HBP, and apparent diffusion coefficients. The primary endpoint was time to recurrence.

RESULTS

In a multivariable adjusted model, the presence of satellite nodules [hazard ratio (HR) 3.07; 95% confidence interval (CI) 1.14-8.24] and peritumoural hypointensity on HBP (HR 4.53; 95% CI 1.52-13.4) were identified as independent factors associated with tumour recurrence. Having either of these radiological findings was associated with a higher tumour recurrence rate (72.5% vs. 15.4% at three years, p <0.001). When patients were stratified according to the Milan criteria, the presence of these two high-risk radiological findings was associated with a higher tumour recurrence rate in both patients transplanted within the Milan criteria (66.7% vs. 11.6% at three years, p <0.001, n = 68) and those who were transplanted outside the Milan criteria (75.5% vs. 28.6% at three years, p <0.001, n = 32).

CONCLUSIONS

Radiological features on preoperative hepatobiliary MRI can stratify the risk of tumour recurrence in patients who were transplanted either within or outside the Milan criteria. Therefore, hepatobiliary MRI can be a useful way to select potential candidates for LT.

LAY SUMMARY

High-risk radiological findings on preoperative hepatobiliary magnetic resonance imaging (either one of the following features: satellite nodule and peritumoural hypointensity on hepatobiliary phase) were associated with a higher tumour recurrence rate in patients transplanted either within or outside the Milan criteria.

Three-Dimensional Bioprinting of Hepatic Structures with Directly Converted Hepatocyte-Like Cells

Three-dimensional (3D) bioprinting technology is a promising new technology in the field of bioartificial organ generation with regard to overcoming the limitations of organ supply. The cell source for bioprinting is very important. Here, we generated 3D hepatic scaffold with mouse-induced hepatocyte-like cells (miHeps), and investigated whether their function was improved after transplantation in vivo. To generate miHeps, mouse embryonic fibroblasts (MEFs) were transformed with pMX retroviruses individually expressing hepatic transcription factors Hnf4a and Foxa3. After 8-10 days, MEFs formed rapidly growing hepatocyte-like colonies. For 3D bioprinting, miHeps were mixed with a 3% alginate hydrogel and extruded by nozzle pressure. After 7 days, they were transplanted into the omentum of Jo2-treated NOD Scid gamma (NSG) mice as a liver damage model. Real-time polymerase chain reaction and immunofluorescence analyses were conducted to evaluate hepatic function. The 3D bioprinted hepatic scaffold (25 × 25 mm) expressed Albumin, and ASGR1 and HNF4a expression gradually increased for 28 days in vitro. When transplanted in vivo, the cells in the hepatic scaffold grew more and exhibited higher Albumin expression than in vitro scaffold. Therefore, combining 3D bioprinting with direct conversion technology appears to be an effective option for liver therapy.

Expanded Criteria for Hepatocellular Carcinoma in Liver Transplant

OBJECTIVES

Hepatocellular carcinoma is the sixth most common cancer worldwide and is the third highest cause of malignancy-related death. Because of its typically late diagnosis, median survival is approximately 6 to 20 months, with 5-year survival of < 12%. Hepatocellular carcinoma typically arises in the background of cirrhosis, with liver transplant regarded as the optimal therapy for selected patients. Initially, orthotopic liver transplant was limited to patients with extensive unresectable tumors, resulting in uniformly dismal outcomes due to high tumor recurrence rates. Here, we evaluated our long-term results with expanded-criteria liver transplant.

MATERIALS AND METHODS

From December 1988 to January 2017, we performed 552 liver transplants at Baskent University. In candidates with hepatocellular carcinoma, our expanded criteria for liver transplant is applied regardless of tumor size and number, includes those without major vascular invasion and without distant metastasis, and those with negative cytology (if the patient has ascites). Since 1994, of 61 liver transplants for hepatocellular carcinoma, 36 patients received transplants according to our expanded criteria.

RESULTS

Of 36 expanded-criteria patients, 11 were children and 25 were adults. Sixteen patients (4 pediatric, 12 adult) were within our expanded criteria both radiologically and pathologically before transplant. The other 20 patients (7 pediatric, 13 adult) were within Milan criteria radiologically before transplant; however, after liver transplant, when pathologic specimens were evaluated, patients were found to be within our center's expanded criteria. During follow-up, 9/36 patients (25%) had hepatocellular carcinoma recurrence. In pediatric patients, 5-year and 10-year survival rates were 90%; in adults, 5-year survival was 58.7% and 10-year survival was 49.7%. Overall 5-year and 10-year survival rates were 71.7% and 62.7%.

CONCLUSIONS

Liver transplant is safe and effective in patients with hepatocellular carcinoma in combination with interventional radiology procedures, regardless of tumor size and number, without major vascular invasion and distant metastasis.

Simple Maturation of Direct-Converted Hepatocytes Derived from Fibroblasts

Target cells differentiation techniques from stem cells are developed rapidly. Recently, direct conversion techniques are introduced in various categories. Unlike pluripotent stem cells, this technique enables direct differentiation into the other cell types such as neurons, cardiomyocytes, insulin-producing cells, and hepatocytes without going through the pluripotent stage. However, the function of these converted cells reserve an immature phenotype. Therefore, we modified the culture conditions of mouse direct converted hepatocytes (miHeps) to mature fetal characteristics, such as higher AFP and lower albumin (ALB) expression than primary hepatocytes. First, we generate miHeps from mouse embryonic fibroblasts (MEFs) with two transcription factors HNF4α and Foxa3. These cells indicate typical epithelial morphology and express hepatic proteins. To mature hepatic function, DMSO is treated during culture time for more than 7 days. After maturation, miHeps showed features of maturation such as exhibiting typical hepatocyte-like morphology, increased up-regulated ALB and CYP enzyme gene expression, down-regulated AFP expressions, and acquired hepatic function over time. Thus, our data provides a simple method to mature direct converted hepatocytes functionally and these cells enable them to move closer to generating functional hepatocytes.

Inflammasome activation involved in early inflammation reaction after liver transplantation

Liver transplantation has emerged as a vital therapy for end-stage liver diseases. Acute -phase inflammation play an important role in liver graft injury.Recent studies have revealed that inflammasome are responsible for initiating inflammation in early stage of acute organ rejection in liver transplantation, however the underlying mechanism remains unclear. Here we explored to block inflammasome activation to see whether it can alleviate early inflammation reaction during rejection of allgrafts in a rat model and gain further insights into the mechanism of inhibiting inflammation in allografts. By using Ac-YVAD-CMK, a highly selective caspase-1 inhibitor, to inhibit inflammation reaction involved in allograft rejection in a rat model. Our results showed that the rejection activity index (RAI) of Ac-YVAD-CMK-treated allografts is significantly diminished in similar magnitude to that of isografts. Compared with isografts, the expression of apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and IL-1β in allograft group increased significantly with the development of rejection, exhibiting apparent correlation. Expression of IFN-γ mRNA in untreated allografts was maximal on day 3 while in Ac-YVAD-CMK-treated allografts and isografts, IFN-γ mRNA levels remained low over the duration of the time course. ELISA results revealed serum elevation of IL-1β by day 7 after othotopic liver transplantation (OLT) in comparison with isografts. There were no statistically significant differences between isografts and Ac-YVAD-CMK-treated allografts. For the first time, our data reveal that inhibition of the inflammasome activation pathway attenuates inflammation reaction of hepatic transplant rejection.

Liver Transplantation is a Preferable Alternative to Palliative Therapy for Selected Patients with Advanced Hepatocellular Carcinoma

BACKGROUND

Patients with hepatocellular carcinoma (HCC) beyond the traditional criteria (advanced HCC) are typically offered palliation, which is associated with a 3-year survival rate lower than 30%. This study aimed to describe the outcomes for a subset of patients with advanced HCC who satisfied the Extended Toronto Criteria (ETC) and were listed for liver transplantation (LT).

METHODS

All patients listed in the Toronto liver transplantation program with HCC beyond both the Milan and University of California, San Francisco criteria were included in this study. Data were extracted from the prospectively collected electronic database. All radiologic images were reviewed by two independent radiologists. The primary end point was patient survival.

RESULTS

Between January 1999 and August 2014, 96 patients with advanced HCC were listed for LT, and 62 (65%) of these patients received bridging therapy while on the waiting list. Bridging therapy led to a significant reduction in tumor progression (p = 0.02) and tumor burden (p < 0.001). The majority of those listed underwent LT (n = 69, 72%). Both tumor progression on waiting list (hazard ratio [HR] 4.973; range1.599-15.464; p = 0.006) and peak alpha-fetoprotein (AFP) at 400 ng/ml or higher (HR, 4.604; range 1.660-12.768; p = 0.003) were independently associated with waiting list dropout. Post-LT HCC recurrence occurred in 35% of the patients (n = 24). Among those with HCC recurrence, survival was significantly better for those who received curative treatment (p = 0.004). The overall actuarial survival rates from the listing were 76% at 1 year, 56% at 3 years, and 47% at 5 years, and the corresponding rates from LT were 93, 71, and 66%.

CONCLUSION

Liver transplantation provides significantly better survival rates than palliation for patients with selected advanced HCC.

When to consider liver transplantation in hepatocellular carcinoma patients?

Orthotopic liver transplantation (LT) has been regarded as the best cure among the three curative treatment modalities. However, when to consider LT in hepatocellular carcinoma (HCC) patients remains a complicated clinical question. In this article, we will look into the recent updates in the context of LT for HCC, including the timing of orthotopic LT (primary or salvage LT), patient selection criteria, newer prognostic markers and scoring systems, down-staging and bridging therapy, salvage LT and treatment option of post-LT HCC recurrence. Evolution of immunosuppressive therapy and future development of the LT for HCC will also be discussed.