A Machine Learning Algorithm Facilitates Prognosis Prediction and Treatment Selection for Barcelona Clinic Liver Cancer Stage C Hepatocellular Carcinoma

BACKGROUND

Given its heterogeneity and diverse clinical outcomes, precise subclassification of BCLC-C hepatocellular carcinoma (HCC) is required for appropriately determining patient prognosis and selecting treatment.

METHODS

We recruited 2,626 patients with BCLC-C stage HCC from multiple centers, comprising training/test (n=1,693) and validation cohorts (n=933). The XGBoost was chosen for maximum performance among the machine learning (ML) models. Patients were categorized into low-/intermediate-/high-/very high-risk subgroups which were based on the estimated prognosis, and this subclassification was named the CLAssification via Machine learning of BCLC-C (CLAM-C).

RESULTS

The areas under the receiver operating characteristic curve of the CLAM-C for predicting the 6-/12-/24-month survival of patients with BCLC-C were 0.800/0.831/0.715, respectively-significantly higher than those of the conventional models, which was consistent in the validation cohort. The four subgroups had significantly different median overall survivals, and this difference was maintained among various patient subgroups and treatment modalities. Immune-checkpoint inhibitors and transarterial therapies were associated with significantly better survival than tyrosine kinase inhibitors (TKIs) in the low- and intermediate-risk subgroups. In cases with first-line systemic therapy, the CLAM-C identified atezolizumab-bevacizumab as the best therapy particularly in the high-risk group. In cases with later-line systemic therapy, nivolumab had better survival than TKIs in the low-to-intermediate-risk subgroup, whereas TKIs had better survival in the high-to-very high-risk subgroup.

CONCLUSIONS

ML modeling effectively subclassified patients with BCLC-C HCC, potentially aiding treatment allocation. Our study underscores the potential utilization of ML modeling in terms of prognostication and treatment allocation in patients with BCLC-C HCC.

Intrahepatic immunoglobulin a complex induces polarization of cancer-associated fibroblasts to matrix phenotypes in the tumor microenvironment of hepatocellular carcinoma

BACKGROUND AND AIMS

Cancer-associated fibroblasts (CAFs) play key roles in the tumor microenvironment (TME). Immunoglobulin A (IgA) contributes to inflammation and dismantling anti-tumor immunity in the human liver. In this study, we aimed to elucidate the effects of the IgA complex on CAFs in the TME of hepatocellular carcinoma (HCC).

APPROACH AND RESULTS

CAF dynamics in HCC TME were analyzed via single-cell RNA sequencing of HCC samples. CAFs isolated from 50 HCC samples were treated with mock or serum-derived IgA dimers in vitro. Progression-free survival of advanced HCC patients treated with atezolizumab and bevacizumab was significantly longer in those with low serum IgA levels (p<0.05). Single-cell analysis showed that sub-cluster proportions in the CAF-fibroblast activation protein-α (FAP) matrix were significantly increased in patients with high serum IgA levels. Flow cytometry revealed a significant increase in the mean fluorescence intensity of FAP in the CD68+ cells from patients with high serum IgA levels (p<0.001). We confirmed CD71 (IgA receptor) expression in CAFs, and IgA-treated CAFs exhibited higher programmed death-ligand 1 (PD-L1) expression levels than those in mock-treated CAFs (p<0.05). Co-culture with CAFs attenuated cytotoxic function of activated CD8+ T cells. Interestingly, activated CD8+ T cells co-cultured with IgA-treated CAFs exhibited increased programmed death-1 (PD-1) expression levels than those co-cultured with mock-treated CAFs (p<0.05).

CONCLUSIONS

Intrahepatic IgA induced polarization of HCC-CAFs into more malignant matrix phenotypes and attenuates cytotoxic T cell function. Our study highlighted their potential roles in tumor progression and immune suppression.

Role of Portosystemic Shunt and Portal Vein Stent in Managing Portal Hypertension Due to Hematological Diseases

INTRODUCTION

Patients with hematological diseases experience complications related to portal hypertension, including life-threatening complications such as variceal bleeding.

METHODS

We analyzed the prognosis of patients with hematological diseases and portal hypertension treated with transjugular intrahepatic portosystemic shunts (TIPS) or portal vein stents. We retrospectively assessed patients with hematological diseases and portal hypertension who had variceal bleeding. We evaluated the characteristics and prognosis of the enrolled patients. A total of 11 patients with hematological diseases who underwent TIPS, or portal vein stenting, were evaluated.

RESULTS

The median follow-up period was 420 days. Of the 11 patients, eight showed resolution of portal hypertension and its complications following TIPS, or stent insertion. One patient experienced rebleeding due to incomplete resolution of portal hypertension, and two other patients also experienced rebleeding because they underwent TIPS closure or revision due to repetitive hepatic encephalopathy.

CONCLUSION

Portosystemic shunt and stent installation are effective treatment options for portal hypertension due to hematological diseases.

Association between the early high level of serum tacrolimus and recurrence of hepatocellular carcinoma in ABO-incompatible liver transplantation

BACKGROUND

Clinical factors predicting graft survival (GS) after ABO-incompatible (ABOi) liver transplantation (LT), and differences between recipients with and without hepatocellular carcinoma (HCC) are unclear.

AIM

To analyze the impact of serial serum tacrolimus trough concentration in recipients with or without HCC) in ABOi living-donor liver transplantation (LDLT).

METHODS

We analyzed a historical cohort of 89 recipients who underwent ABOi LDLT, including 47 patients with HCC.

RESULTS

The 1-, 3-, 5-, and 10-year GS rates were 85.9%, 73.3%, 71.4%, and 71.4%, respectively, and there were no significant differences between HCC and non-HCC recipients. In multivariate Cox-regression analyses, tacrolimus trough concentrations below 5.4 ng/mL at 24 wk post-LT, in addition to the antibody-mediated rejection (AMR) were associated with poor-graft outcomes. In HCC patients, AMR [hazard ratio (HR) = 63.20, P < 0.01] and HCC recurrence (HR = 20.72, P = 0.01) were significantly associated with poor graft outcomes. HCCs outside Milan criteria, and tacrolimus concentrations at 4 wk post-LT > 7.3 ng/mL were significant predictive factors for HCC recurrence. After propensity score matching, patients with high tacrolimus concentrations at 4 wk had significantly poor recurrence-free survival.

CONCLUSION

Elevated tacrolimus levels at 4 wk after ABOi LDLT have been found to correlate with HCC recurrence. Therefore, careful monitoring and control of tacrolimus levels are imperative in ABOi LT recipients with HCC.

A Real-World Comparative Analysis of Atezolizumab Plus Bevacizumab and Transarterial Chemoembolization Plus Radiotherapy in Hepatocellular Carcinoma Patients with Portal Vein Tumor Thrombosis

This study aimed to compare the treatment outcomes of atezolizumab-plus-bevacizumab (Ate/Bev) therapy with those of transarterial chemoembolization plus radiotherapy (TACE + RT) in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) and without metastasis. Between June 2016 and October 2022, we consecutively enrolled 855 HCC patients with PVTT. After excluding 758 patients, 97 patients (n = 37 in the Ate/Bev group; n = 60 in the TACE + RT group) were analyzed. The two groups showed no significant differences in baseline characteristics and had similar objective response and disease control rates. However, the Ate/Bev group showed a significantly higher one-year survival rate (p = 0.041) compared to the TACE + RT group, which was constantly displayed in patients with extensive HCC burden. Meanwhile, the clinical outcomes were comparable between the two groups in patients with unilobar intrahepatic HCC. In Cox-regression analysis, Ate/Bev treatment emerged as a significant factor for better one-year survival (p = 0.049). Finally, in propensity-score matching, the Ate/Bev group demonstrated a better one-year survival (p = 0.02) and PFS (p = 0.01) than the TACE + RT group. In conclusion, Ate/Bev treatment demonstrated superior clinical outcomes compared to TACE + RT treatment in HCC patients with PVTT. Meanwhile, in patients with unilobar intrahepatic HCC, TACE + RT could also be considered as an alternative treatment option alongside Ate/Bev therapy.

Comparative Analysis of Atezolizumab Plus Bevacizumab and Hepatic Artery Infusion Chemotherapy in Unresectable Hepatocellular Carcinoma: A Multicenter, Propensity Score Study

This study aimed to compare the prognosis and characteristics of patients with advanced hepatocellular carcinoma treated with first-line atezolizumab plus bevacizumab (AB) combination therapy and hepatic artery infusion chemotherapy (HAIC). We retrospectively assessed 193 and 114 patients treated with HAIC and AB combination therapy, respectively, between January 2018 and May 2023. The progression-free survival (PFS) of patients treated with AB combination therapy was significantly superior to that of patients treated with HAIC (p < 0.05), but there was no significant difference in overall survival (OS). After propensity score matching, our data revealed no significant differences in OS and PFS between patients who received AB combination therapy and those who received HAIC therapy (p = 0.5617 and 0.3522, respectively). In conclusion, our propensity score study reveals no significant differences in OS and PFS between patients treated with AB combination therapy and those treated with HAIC.

Higher Number of Tumor-Infiltrating PD-L1+ Cells Is Related to Better Response to Multikinase Inhibitors in Hepatocellular Carcinoma

Multikinase inhibitors (MKIs) such as sorafenib and lenvatinib are first-line treatments for unresectable hepatocellular carcinoma (HCC) and are known to have immunomodulatory effects. However, predictive biomarkers of MKI treatment in HCC patients need to be elucidated. In the present study, thirty consecutive HCC patients receiving lenvatinib (n = 22) and sorafenib (n = 8) who underwent core-needle biopsy before treatment were enrolled. The associations of CD3, CD68, and programmed cell death-ligand-1 (PD-L1) immunohistochemistry with patient outcomes, including overall survival (OS), progression-free survival (PFS), and objective response rate (ORR), were evaluated. High and low subgroups were determined according to median CD3, CD68, and PD-L1 values. Median CD3 and CD68 counts were 51.0 and 46.0 per 20,000 µm², respectively. The median combined positivity score (CPS) of PD-L1 was 2.0. Median OS and PFS were 17.6 and 4.4 months, respectively. ORRs of the total, lenvatinib, and sorafenib groups were 33.3% (10/30), 12.5% (1/8), and 40.9% (9/22), respectively. The high CD68+ group had significantly better PFS than the low CD68+ group. The high PD-L1 group had better PFS than the low subgroup. When we analyzed the lenvatinib subgroup, PFS was also significantly better in the high CD68+ and PD-L1 groups. These findings suggest that high numbers of PD-L1-expressing cells within tumor tissue prior to MKI treatment can serve as a biomarker to predict favorable PFS in HCC patients.

Factors associated with the survival outcomes of patients with untreated hepatocellular carcinoma: An analysis of nationwide data

Introduction

In this study, we examined the natural course of untreated hepatocellular carcinoma (HCC) and identified predictors of survival in an area where hepatitis B is the predominant cause of HCC.

Methods

We identified 1,045 patients with HCC who did not receive HCC treatment and were registered in the Korean Primary Liver Cancer Registry between 2008 and 2014, and were followed-up up to December 2018. Thereafter, we analyzed the clinical characteristics of patients who survived for <12 or ≥12 months. A Cox proportional regression model was used to identify the variables associated with patient survival.

Results and discussion

The mean age of the untreated patients at HCC diagnosis was 59.6 years, and 52.1% of patients had hepatitis B. Most untreated patients (94.2%) died during the observation period. The median survival times for each Barcelona Clinic Liver Cancer (BCLC) stage were as follows: 31.0 months for stage 0/A (n = 123), 10.0 months for stage B (n = 96), 3.0 months for stage C (n = 599), and 1.0 month for stage D (n = 227). Multivariate Cox regression analysis demonstrated that BCLC stage D (hazard ratio, 4.282; P < 0.001), model for end-stage liver disease (MELD) score ≥10 (HR, 1.484; P < 0.001), and serum alpha-fetoprotein (AFP) level ≥1,000 ng/mL (HR, 1.506; P < 0.001) were associated with poor survival outcomes in patients with untreated HCC. In untreated patients with HCC, advanced stage BCLC, serum AFP level ≥1,000 ng/mL, and MELD score ≥10 were significantly associated with overall survival.

An Immunological Perspective on the Mechanism of Drug Induced Liver Injury: Focused on Drugs for Treatment of Hepatocellular Carcinoma and Liver Transplantation

The liver is frequently exposed to potentially toxic materials, and it is the primary site of clearance of foreign agents, along with many innate and adaptive immune cells. Subsequently, drug induced liver injury (DILI), which is caused by medications, herbs, and dietary supplements, often occurs and has become an important issue in liver diseases. Reactive metabolites or drug-protein complexes induce DILI via the activation of various innate and adaptive immune cells. There has been a revolutionary development of treatment drugs for hepatocellular carcinoma (HCC) and liver transplantation (LT), including immune checkpoint inhibitors (ICIs), that show high efficacy in patients with advanced HCC. Along with the high efficacy of novel drugs, DILI has become a pivotal issue in the use of new drugs, including ICIs. This review demonstrates the immunological mechanism of DILI, including the innate and adaptive immune systems. Moreover, it aims to provide drug treatment targets, describe the mechanisms of DILI, and detail the management of DILI caused by drugs for HCC and LT.

Genotype-Phenotype Association in ABCC2 Exon 18 Missense Mutation Leading to Dubin-Johnson Syndrome: A Case Report

We report a case of a patient with Dubin-Johnson syndrome confirmed by a genetic study. A 50-year-old woman who had symptoms of intermittent right upper quadrant abdominal pain was diagnosed with calculous cholecystitis at another institute and was presented to our hospital for a cholecystectomy. She had no history of liver disease, and her physical examination was normal. Abdominal computed tomography showed a gallbladder stone with chronic cholecystitis. During a laparoscopic cholecystectomy for cholecystitis, a smooth, black-colored liver was noted, and a liver biopsy was performed. The biopsy specimen showed coarse, dark brown granules in centrilobular hepatocytes via hematoxylin and eosin staining. We performed a genetic study using the blood samples of the patient. In the adenosine triphosphate-binding cassette subfamily C member 2 (ABCC2) mutation study, a missense mutation in exon 18 was noted. Based on the black-colored liver without nodularity, conjugated hyperbilirubinemia, the liver biopsy results of the coarse pigment in centrilobular hepatocytes, and the ABCC2 mutation, Dubin-Johnson syndrome was diagnosed. The patient was managed with conservative care using hepatotonics. One month after follow-up, total bilirubin and direct bilirubin remained in a similar range. Another follow-up was planned a month later, and the patient maintained her use of hepatotonics.

Real-life experience of ledipasvir and sofosbuvir for HCV infected Korean patients: a multicenter cohort study

BACKGROUND/AIMS

To evaluate the efficacy and safety of ledipasvir/sofosbuvir (LDV/SOF) therapy in hepatitis C virus (HCV)-infected Korean patients in a real clinical setting.

METHODS

A total of 273 patients who received LDV/SOF therapy between May 2016 and February 2021 were consecutively enrolled and analyzed. A per-protocol analysis was performed to evaluate the virologic response.

RESULTS

Seventy-five percent were infected with genotype 1, and 25% were infected with genotype 2. A hundred eightyone (66.3%) patients had chronic hepatitis, 74 (27.1%) had compensated cirrhosis, eight (2.9%) had decompensated cirrhosis, and 10 (3.7%) had undergone liver transplantation. Undetectable HCV RNA at week 4 was achieved in 90.2% (231/256) of patients, 99.2% (250/252) achieved the end of treatment response, and 98.1% (202/206) achieved sustained virologic response at 12 weeks post-treatment (SVR12). According to liver function, the SVR12 rates were 99.3% (135/136) in chronic hepatitis, 96.4% (53/55) in compensated cirrhosis, and 100% (6/6) in decompensated cirrhosis. The SVR12 rates according to the genotype were 98.2% (167/170) for genotype 1 and 97.2% (35/36) for genotype 2. An 8-week LDV/SOF treatment in treatment-naïve chronic hepatitis patients with HCV RNA &lt; 6,000,000 IU/mL at baseline resulted in 100% (23/23) SVR12 rates. Overall, LDV/SOF was tolerated well, with a 0.7% (2/273) discontinuation rate due to adverse events that were unrelated to LDV/SOF.

CONCLUSION

LDV/SOF is effective and safe for treating HCV-infected Korean patients with high SVR12 rates.

Blood-based biomarkers for immune-based therapy in advanced HCC: Promising but a long way to go

The introduction of immune checkpoint inhibitors (ICIs) represents a key shift in the management strategy for patients with hepatocellular carcinoma (HCC). However, there is a paucity of predictive biomarkers that facilitate the identification of patients that would respond to ICI therapy. Although several researchers have attempted to resolve the issue, the data is insufficient to alter daily clinical practice. The use of minimally invasive procedures to obtain patient-derived specimen, such as using blood-based samples, is increasingly preferred. Circulating tumor DNA (ctDNA) can be isolated from the blood of cancer patients, and liquid biopsies can provide sufficient material to enable ongoing monitoring of HCC. This is particularly significant for patients for whom surgery is not indicated, including those with advanced HCC. In this review, we summarize the current state of understanding of blood-based biomarkers for ICI-based therapy in advanced HCC, which is promising despite there is still a long way to go.

MiR-23b-3p suppresses epithelial-mesenchymal transition, migration, and invasion of hepatocellular carcinoma cells by targeting c-MET

Background

Aberrant expression of c-MET is known to be associated with tumor recurrence and metastasis by promoting cell proliferation, epithelial-mesenchymal transition (EMT), and migration in hepatocellular carcinoma (HCC). Recently, miR-23b-3p has been identified as a tumor suppressor, but detailed role of miR-23b-3p in HCC is still unclear. Our study aimed to investigate how miR-23b-3p is associated with the malignant potential of HCC cells.

Methods

HCC tissues and their adjacent non-tumor tissues were acquired from 30 patients with HCC. Expression of EMT- or stemness-related genes were examined in the two HCC cell lines. Migration of HCC cells was analyzed using transwell and wound healing assays.

Results

c-MET was overexpressed in HCC tissues compared to the adjacent non-tumor tissues. c-MET knockdown inhibited EMT and reduced migration and invasion of HCC cells. Furthermore, c-MET was a target of miR-23b-3p, and miR-23b-3p expression was decreased in HCC tissues compared to non-tumor tissues. Treatment of miR-23b-3p inhibitor in HCC cells promoted EMT, cell migration, and invasion. In contrast, miR-23b-3p overexpression suppressed EMT, cell migration, and invasion, concomitantly reducing c-MET expression. Transfection of miR-23b-3p inhibitor with concomitant c-MET knockdown mitigated the effects of miR-23b-3p inhibitor on EMT in HCC cells. In addition, transforming growth factor beta1 (TGF-β1) stimulation after miR-23b-3p overexpression induced neither the mesenchymal phenotype nor migratory property of HCC cells.

Conclusion

In this study, we confirmed that miR-23b-3p downregulation significantly increased EMT, migration, and invasion of HCC cells. In addition, c-MET was confirmed to be a target of miR-23b-3p in HCC cells and regulated the functional effects of miR-23b-3p. These results suggest that miR-23b-3p can be used as a prognostic biomarker and candidate target for HCC treatment.

•

c-MET is a target of miR-23b-3p and overexpressed in HCC tissues.

•

MiR-23b-3p expression was decreased in HCC tissues compared to non-tumor tissues.

•

Inhibition of miR-23b-3p induced migration and invasion via EMT in HCC cells.

•

MiR-23b-3p/c-MET axis may serve as a therapeutic target for HCC.

A risk prediction model for hepatocellular carcinoma after hepatitis B surface antigen seroclearance

BACKGROUND & AIMS

After hepatitis B surface antigen (HBsAg) seroclearance, the risk of hepatocellular carcinoma (HCC) remains, and the optimal surveillance strategy has yet to be determined. Herein, we aimed to evaluate incidence and risk factors for HCC and establish a novel prediction model for HCC development after HBsAg seroclearance.

METHODS

A total of 1,443 patients with chronic hepatitis B who achieved HBsAg seroclearance between 1991 and 2020 were retrospectively screened for study eligibility. The data from 831 of these patients were included in the final analysis. A prediction model was developed based on multivariable Cox models. Harrell's C-index and a time-dependent AUROC were used for discrimination. Bootstrap analysis was performed for internal validation.

RESULTS

Overall, 40 patients (4.8%) developed HCC after HBsAg seroclearance during a follow-up of 4,644 person-years (0.86%/year). Age at HBsAg seroclearance, presence of cirrhosis, family history of HCC, and more-than-moderate alcohol consumption were independently predictive of HCC, and these 4 independent variables were used to develop the prediction model. The C-index of the model was 0.804. The time-dependent AUROCs of the score for HCC prediction at 5, 10, and 15 years were 0.799, 0.835, and 0.817, respectively. The score also showed good discrimination in the internal validation and sensitivity analysis.

CONCLUSIONS

The novel prediction model based on age, cirrhosis, family history of HCC, and alcohol consumption enables reliable risk estimation of HCC after HBsAg seroclearance and may serve as a useful reference for decision-making in HCC surveillance for HBsAg-cleared patients.

LAY SUMMARY

After spontaneous hepatitis B surface antigen (HBsAg) seroclearance, the risk of hepatocellular carcinoma (HCC) remains. Age at HBsAg seroclearance, presence of cirrhosis, family history of HCC, and more-than-moderate alcohol consumption were independently associated with HCC development after HBsAg seroclearance. The novel prediction model using these 4 variables enables reliable risk estimation of HCC and serves as a useful reference for decision-making in HCC surveillance and management for HBsAg-cleared patients.

Safety and effectiveness of direct-acting antivirals in patients with chronic hepatitis C and chronic kidney disease

BACKGROUND/AIMS

To evaluate the effectiveness and safety of direct acting antivirals (DAAs) available in chronic kidney disease (CKD) patients with hepatitis C virus (HCV) infection in Korea.

METHODS

In a retrospective, multicenter cohort study, 362 patients were enrolled from 2015 to 2019. The effectiveness and safety of DAAs including glecaprevir/pibrentasvir, sofosubvir/ribavirin, ledipasvir/sofosbuvir, and daclatasvir/asunaprevir were analyzed for patients according to CKD stage. We evaluated sustained virologic response at week 12 after treatment (SVR12) as primary endpoint. The effectiveness and safety were also evaluated according to CKD stage.

RESULTS

Among 362 patients, 307 patients completed DAAs treatment and follow-up period after end of treatment. The subjects comprised 87 patients (62 with CKD stage 3 and 25 with CKD stage (4-5), of whom 22 were undergoing hemodialysis). HCV patients with CKD stage 1 and 2 (estimated glomerular filtration rate [eGFR] ≥ 60 mL/min/1.73 m2) showed SVR12 of 97.2% and 95.4% respectively. SVR12 of CKD stage 3 and 4-5 (eGFR &lt; 60 mL/min/1.73 m2) patients was 91.9% and 91.6% respectively. Patients undergoing hemodialysis achieved SVR12 (90.9%). Treatment failure of DAAs in stage 1, 2, 3, and 4-5 was 2.8%, 2.7%, 1.6%, and 4%. DAAs showed good safety profile and did not affect deterioration of renal function.

CONCLUSION

DAAs shows comparable SVR12 and safety in CKD patients (stage 3, 4, and 5) with HCV compared with patients with stage 1 and 2. The effectiveness and safety of DAAs may be related to the treatment duration. Therefore, it is important to select adequate regimens of DAAs and to increase treatment adherence.

Multidisciplinary approach for hepatocellular carcinoma arising from cirrhotic liver with Budd-Chiari syndrome: a case report

Budd-Chiari syndrome (BCS) is defined by the obstruction of the hepatic venous outflow between the small hepatic veins and the junction of the inferior vena cava (IVC) with the right atrium. BCS with IVC obstruction occasionally progresses to hepatocellular carcinoma (HCC). Here, we report the case of a patient with HCC arising from a cirrhotic liver with BCS, in whom the hepatic portion of the IVC was obstructed, and who had a favorable outcome with a multidisciplinary approach and IVC balloon angioplasty.

A decrease in functional microbiomes represented as Faecalibacterium affects immune homeostasis in long-term stable liver transplant patients

LT, liver transplantation; HCC, hepatocellular carcinoma; IS, immunosuppressants; DC, dendritic cells; Treg, regulatory T; Th17, T helper 17; AST, aspartate transaminase; ALT, alanine transaminase; OUT, operational taxonomic unit; LEfSe, linear discriminant analysis effect size; LDA, linear discriminant analysis; IL, interleukin; TGF, transforming growth factor; GM-CSF, granulocyte-macrophage colony-stimulating factor; IFN, interferon; TNF-α, tumor necrosis factor-α; MIP-1α, macrophage inflammatory protein-1α; IP-10, interferon γ-induced protein; MCP-1, monocyte chemoattractant protein-1; ACR, acute cellular rejection; NF-κB, nuclear factor κB; PT INR, prothrombin time; QC, quality check; PBMC, peripheral blood mononuclear cells; PBS, phosphate-buffered saline; ELISA, enzyme-linked immunosorbent assay.

Enhanced Tumoricidal Immune Responses by Transarterial Chemotherapy Using Novel Nanocomplexes in a Rat Liver Cancer Model

BACKGROUND/AIM

Locoregional treatments for hepatocellular carcinoma (HCC) induce immunogenic cell death and a tumor-specific immune response, but infiltration and activation of immune cells in the liver have not been clearly described. Transarterial chemoembolization (TACE) or transarterial chemotherapy (TAC) without embolization have been used to treat intermediate or advanced stage HCC patients. The identification of intrahepatic immune cell changes after locoregional therapy provides a theoretical basis for the combination with immune checkpoint inhibitors (ICIs) in HCC. This study aimed to determine the anticancer effect and changes in the liver immune cell population and function after direct injection of polymerized phenylboronic acid-conjugated doxorubicin (pPBA-Dox) nanocomplexes into the liver through TAC.

MATERIALS AND METHODS

pPBA-Dox nanocomplexes were delivered directly to the liver cancer in a rat model by transarterial methods. Anticancer effect was confirmed by magnetic resonance imaging (MRI), and the immune cell population and functional changes were confirmed by flow cytometry (FACS).

RESULTS

We first established a rat liver cancer model by implanting McA-RH7777 into rats and confirmed the formation of liver cancer through MRI, pathological examinations, and biochemical tests. Transarterial injection of pPBA-Dox nanocomplexes had a stronger anticancer effect than conventional Dox alone. Higher numbers of CD8⁺ and CD4⁺ T cells with activated phenotypes were infiltrated into the tumor microenvironment after transarterial pPBA-Dox treatments than after Dox alone treatment, suggesting the induction of stronger local immune responses by pPBA-Dox than Dox alone.

CONCLUSION

This study provides a theoretical basis for TAC combined with ICIs and insight into novel targeted therapies using nanocomplexes for the treatment of HCC.

Intrahepatic inflammatory IgA+PD-L1high monocytes in hepatocellular carcinoma development and immunotherapy

Background

IgA neutralizes pathogens to prevent infection at mucosal sites. However, emerging evidence shows that IgA contributes to aggravating inflammation or dismantling antitumor immunity in human diseased liver. The aim of this study was to elucidate the roles of inflammation-induced intrahepatic inflammatory IgA⁺ monocytes in the development of hepatocellular carcinoma (HCC).

Methods

Patient cohorts including steatohepatitis cohort (n=61) and HCC cohort (n=271) were established. Patients’ surgical and biopsy specimens were analyzed using immunohistochemistry. Multicolor flow cytometry was performed with a subset of patient samples. Single-cell RNA-Seq analysis was performed using Gene Expression Omnibus (GEO) datasets. Additionally, we performed in vitro differentiation of macrophages, stimulation with coated IgA, and RNA sequencing. Hepa1-6 cells and C57BL/6N mice were used to obtain HCC syngeneic mouse models.

Results

Serum IgA levels were associated (p<0.001) with fibrosis progression and HCC development in patients with chronic liver diseases. Additionally, immunohistochemical staining of inflamed livers or HCC revealed IgA positivity in monocytes, with a correlation between IgA⁺ cell frequency and IgA serum levels. Compared with IgA⁻ monocytes, intrahepatic IgA⁺ monocytes expressed higher levels of programmed death-ligand 1 (PD-L1) in inflamed livers and in HCC tumor microenvironment. Single-cell RNA sequencing using NCBI GEO database indicated an upregulation in inflammation-associated genes in the monocytes of patients whose plasma cell IGHA1 expression was greater than or equal to the median value. Bulk RNA sequencing demonstrated that in vitro stimulation of M2-polarized macrophages using coated IgA complex induced PD-L1 upregulation via YAP-mediated signaling. In vivo blockade of IgA signaling decreased the number of tumor-infiltrating IgA⁺PD-L1^high macrophages and increased the number of CD69⁺CD8⁺ T cells to enhance antitumor effects in HCC mice models.

Conclusions

Overall, the findings of this study showed that serum IgA levels was correlated with intrahepatic and intratumoral infiltration of inflammatory IgA⁺PD-L1^high monocytes in chronic liver diseases and HCC, providing potential therapeutic targets.

Patient-Derived Avatar Mouse Model to Predict the Liver Immune Homeostasis of Long-Term Stable Liver Transplant Patients

Although rejection or tolerance can occur in liver transplantation (LT) patients, there are no reliable non-invasive methods for predicting immune homeostasis. In this study, we developed a humanized mouse model to predict liver immune homeostasis in patients who underwent LT. The patient-derived avatar model was developed by injecting peripheral blood mononuclear cells from healthy controls (HCs) or LT patients with stable, rejection, or tolerance into NOD.Cg-Prkdc^scidIL2rg^tm1Wjl/SzJ (NSG) mice, followed by injection of human hepatic stellate cells and Carbone tetrachloride (CCl₄). After 7 weeks, the patient’s T-cell engraftment and liver inflammation in the avatar model were evaluated and compared with the liver histology of LT patients. Changes in liver inflammation following treatment with tacrolimus and/or biguanide derivatives were also examined. The C-X-C Motif Chemokine Receptor 3 (CXCR3)-dependently engrafted patient T cells led to differences in liver inflammation in our model according to the status of LT patients. The livers of avatar models from rejection patients had severe inflammation with more T helper 17 cells and fewer regulatory T cells compared to those of models from tolerance and HCs showing only mild inflammation. Moreover, our model classified stable post-LT patients into severe and mild inflammation groups, which correlated well with liver immunity in these patients. Our models revealed alleviation of inflammation after combination treatment with tacrolimus and biguanide derivatives or monotherapy. Consequently, using our new patient-derived avatar model, we predicted liver immune homeostasis in patients with stable LT without biopsy. Moreover, our avatar model may be useful for preclinical analysis to evaluate treatment responses while reducing risks to patients.

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.

Diagnostic performance of serum exosomal miRNA-720 in hepatocellular carcinoma

Background/Aim

Hepatocellular carcinoma (HCC) is associated with poor prognosis, largely due to late detection. Highly accurate biomarkers are urgently needed to detect early-stage HCC. Our study aims to explore the diagnostic performance of serum exosomal microRNA (miR)-720 in HCC.

Methods

Exosomal miRNA was measured via quantitative real-time PCR. A correlation analysis of exosomal miR-720 and tumor or clinico-demographic data of patients with HCC was performed. The receiver operating characteristic (ROC) curve was used to assess the diagnostic capacity of serum exosomal miR-720 for HCC, in comparison with α-fetoprotein (AFP) and prothrombin induced by vitamin K absence or antagonist-II (PIVKA-II).

Results

MiR-720 was chosen as a potential HCC marker via miR microarray based on significant differential expression between tumor and non-tumor samples. Serum exosomal miR-720 was significantly upregulated in patients with HCC (n=114) versus other liver diseases (control, n=30), with a higher area under the ROC curve (AUC, 0.931) than the other markers. Particularly, serum exosomal miR-720 showed superior performance in diagnosing small HCC (<5 cm; AUC, 0.930) compared with AFP (AUC, 0.802) or PIVKA-II (AUC, 0.718). Exosomal miR-720 levels showed marginal correlation with tumor size. The proportion of elevated miR-720 also increased with intrahepatic tumor stage progression. Unlike AFP or PIVKA-II showing a significant correlation with aminotransferase levels, the exosomal miR-720 level was not affected by aminotransferase levels.

Conclusions

Serum exosomal miR-720 is an excellent biomarker for the diagnosis of HCC, with better performance than AFP or PIVKA-II. Its diagnostic utility is maintained even in small HCC and is unaffected by aminotransferase levels.

Anti-fibrotic effects of branched-chain amino acids on hepatic stellate cells

BACKGROUND/AIMS

Patients with liver cirrhosis (LC) have low levels of branched-chain amino acids (BCAAs). There is accumulating evidence that BCAAs have anti- fibrotic effects in cirrhosis. This study is aimed to evaluate the effect of BCAAs on the function and phenotype of activated hepatic stellate cells (HSCs).

METHODS

LX-2, an immortalized human stellate cell line, was used in in vitro experiments. LX-2 cells were exposed to transforming growth factor β1 (TGF-β1) and BCAAs or to valine, leucine, and isoleucine, which are components of BCAAs. Activation of the TGF-β signaling pathway in LX-2 cells was observed using real-time quantitative polymerase chain reaction and Western blotting.

RESULTS

The increased expression of snail family transcriptional repressor 1 (SNAI1) was observed in LX-2 cells activated by TGF-β1. After BCAA treatment, its expression was significantly decreased at the mRNA level. The increased expression of Col1α1 and TIMP2 at the mRNA level and alpha smooth muscle actin at the protein level in activated LX-2 cells decreased after BCAA treatment. Among the BCAA components, leucine and valine significantly abrogated TGF-β-induced activation of LX-2 cells. BCAA treatment led to the decreased phosphorylation of Smad2 and p38 proteins, which are markers for Smad and Smad-independent p38 mitogen-activated protein kinase signaling pathways, respectively.

CONCLUSION

BCAA treatment can improve hepatic fibrosis by directly affecting the activated state of hepatic stellate cells through inhibition of the TGF-β signaling pathway. Among BCAA components, leucine and valine mainly abrogated TGF-β-induced activation of HSCs. Our results suggest that BCAA may be used to attenuate the progression of liver fibrosis.

Tenofovir disoproxil fumarate directly ameliorates liver fibrosis by inducing hepatic stellate cell apoptosis via downregulation of PI3K/Akt/mTOR signaling pathway

Background

Antifibrotic agent for the treatment of liver fibrosis has not been developed so far. Long term treatment of chronic hepatitis B patients with antiviral drugs tenofovir disoproxil fumarate (TDF) and entecavir (ETV) results in the regression of liver fibrosis, but the underlying mechanism has not been clarified. Therefore, we aimed to investigate the direct impact of TDF and ETV on liver fibrosis.

Methods

Activated hepatic stellate cell (HSC) cell lines were used to evaluate the effects of TDF and ETV. After treatment with each antiviral agent, cell viability, morphology, apoptotic features, autophagy and antifibrosis signalling pathways were examined. Then, collagen deposition, fibrosis markers and activated HSCs were measured in liver tissues of the liver fibrosis model mice.

Results

After TDF treatment, the viabilities of LX2 and HSC-T6 cells were decreased, and the cells exhibited apoptotic features, but ETV did not induce these effects. Cleavage of PARP and Caspase-3 and the inhibition of the antiapoptotic gene Bcl-xl indicated activated HSC apoptosis following TDF treatment. TDF simultaneously increased autophagy, which also regulated apoptosis through crosstalk. TDF inactivated the PI3K/Akt/mTOR signalling pathway, which was associated with the activation of both apoptosis and autophagy. In the liver fibrosis mouse model, the fibrotic area and activated HSC markers were decreased by TDF but not ETV treatment. Additionally, apoptotic cells were concentrated in the periportal fibrotic area after TDF treatment, which indicated the specific antifibrotic effect of TDF.

Conclusions

TDF directly ameliorates liver fibrosis by downregulating the PI3K/Akt/mTOR signalling pathway, which results in the apoptosis of activated HSCs. The antifibrotic effects of TDF indicate that it may be a therapeutic agent for the treatment of liver fibrosis.

Whole blood viscosity is associated with extrahepatic metastases and survival in patients with hepatocellular carcinoma

Whole blood viscosity (WBV) is increased in cancer patients and associated with the advanced stage with systemic metastases. However, relevance of WBV in hepatocellular carcinoma (HCC) remains unclear. This pilot study included a discovery cohort of 148 treatment-naïve HCC patients with preserved liver function, and a validation cohort of 33 treatment-experienced HCC patients with nivolumab. Systolic and diastolic WBV was measured using an automated scanning capillary tube viscometer at diagnosis or before the nivolumab treatment. Extrahepatic metastases were observed in 15 treatment-naïve patients (11.3%) at diagnosis. Portal vein tumor thrombosis (PVTT), tumor size, number of tumors, and systolic/diastolic WBV were factors associated with extrahepatic metastases. Systolic WBV and diastolic WBV were significantly increased in patients with metastases compared with patients without metastases. Multivariate logistic regression showed that high diastolic WBV > 16 cP was an independent factor associated with metastases. Notably, patients who developed extrahepatic metastases during the observation period among patients without metastases at diagnosis had higher diastolic WBV initially. Patients with high diastolic WBV had poor survival, and multivariate Cox regression analyses showed high diastolic WBV was an independent risk factor for poor survival with the Child-Pugh B7 and PVTT. High diastolic WBV also predicted poor survival in patients with low alpha-fetoprotein (AFP) and proteins induced by vitamin K antagonist-II (PIVKA-II) levels. In 33 nivolumab-treated patients, high diastolic WBV before the treatment was also tended to be associated with overall and progression-free survival. Our study is the first in which high WBV is associated with the distant metastases and survival in patients with HCC, but future prospective, large cohort studies are necessary to validate the results.

Determination of infectious hepatitis B virus particles by an end-point dilution assay identifies a novel class of inhibitors

The quantification of infectious virus particles is fundamental to perform in vitro virology studies. To determine the number of hepatitis B virus (HBV) genome-containing particles in vitro, the genome equivalents (GEq) are measured using quantitative PCR (qPCR). However, in addition to infectious virions, HBV DNA-containing, non-infectious HBV particles are also produced in vitro, which can lead to an over-estimation of the number of infectious HBV particles when analyzed by qPCR. Here, we establish an end-point dilution assay that can precisely determine the number of infectious HBV particles. The cell-based HBV infection assay uses a 384-well plate format and enables the calculation of the 50% tissue culture infective dose (TCID₅₀) in a semi-automated manner. Cell culture-derived HBV (HBVcc), produced by either stable HBV-replicating cells (HepAD38) or HBV-infected HepG2-NTCP cells, as well as patient-derived HBV sera were serially diluted and used to infect naïve target cells. Applying the end-point dilution assay, we infected HepG2-NTCP cells with PEG precipitated HBV derived from HepAD38-and HepG2-NTCPsec+ cell supernatants, calculated the TCID₅₀/mL, converted to plaque-forming units (PFUs), and generated the specific infectivity (ratio of PFU/GEq). As a result, a TCID₅₀/mL of 7.22 × 10⁶ and 2.16 × 10⁶, and the specific infectivity of 1/13,816 and 1/8798 were calculated for HepAD38 and HepG2-NTCPsec+ cell supernatants, respectively. The specific infectivity further increased by approximately 2-fold after removal of non-infectious "naked" particles by immunoprecipitation. Purification of HepAD38 cell supernatants by heparin columns increased the TCID₅₀/mL and specific infectivity by 18- and 15-fold, respectively. Interestingly, non-purified patient-derived HBV sera from two individuals had a specific infectivity of 1/88 and 1/3609. After converting TCID₅₀ to multiplicity of infection (MOI) values, we inoculated HepG2-NTCP cells with HBVcc based on GEq or MOI values and demonstrated that MOI-based infection leads to more reproducible infection rates. Furthermore, the assay was validated using serially diluted lamivudine, an HBV replication inhibitor, inhibiting HBV DNA secretion and infectious viral progeny by approx. 56- and 470-fold, respectively. Interestingly, we identified dexmedetomidine (DMM), an alpha-2 adrenergic agonist, inhibiting the secretion of infectious viral progeny by approx. 6-fold, without interfering in the secretion of HBV DNA. Taken together, we developed an assay that is suitable for the standard quantification of infectious HBV particles. We identified DMM as a novel inhibitor that exclusively interferes with the secretion of infectious HBV particles without affecting the secretion of HBV genomes. This end-point dilution assay enables the precise determination of the number of infectious HBV particles, assessment of the specific infectivity and stability of HBV particles, and identification of novel classes of HBV inhibitors.

Use of M2BPGi in HCC patients with TACE

BACKGROUND AND AIM

Serum Mac-2-binding protein glycosylation isomer (M2BPGi) has been studied as a marker for liver fibrosis or cirrhosis. This study explores the potential role of M2BPGi in predicting clinical outcomes of patients with hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE).

METHODS

A total of 226 HCC patients undergoing TACE were enrolled. Serum M2BPGi was measured at baseline. Receiver operating characteristic curve analysis was used to determine the cut-off value (= 2.82) of M2BPGi for prediction of patient outcomes. The prognostic performance of M2BPGi was compared with the hepatoma arterial embolization prognostic (HAP) score. The primary outcome was progression-free survival (PFS). Secondary outcomes included overall survival (OS), radiologic response, and recurrence after complete response (CR).

RESULTS

Median PFS was 14.5 months. Patients with low M2BPGi levels had significantly better OS and PFS than those with high M2BPGi levels. M2BPGi was an independent variable for PFS and OS. Patients were classified into three groups by combination of M2BPGi and the HAP score. The low-risk group had significantly better PFS and OS than the high-risk and intermediate-risk groups, whereas the differences between the high-risk and intermediate-risk groups were insignificant. The combination showed higher area under the receiver operating characteristic curve for 3-year PFS and OS than the HAP score alone. M2BPGi was a significant predictor of HCC recurrence after achieving CR.

CONCLUSIONS

Serum M2BPGi level is a useful prognostic indicator of PFS and OS in TACE-treated HCC patients, as well as recurrent cases, which cannot be predicted with the HAP score. The combination of M2BPGi and the HAP score enhances the detection of TACE-preferred patients.

Effects of Positive Hepatitis B Core Antibody and Metabolic Disorders in Hepatocellular Carcinoma in an Endemic Area of Hepatitis B Virus

BACKGROUND AND AIMS

This retrospective study aimed to investigate the impact of positive hepatitis B core antibody (anti-HBc) and metabolic disorders on clinical characteristics of hepatocellular carcinoma (HCC) patients in an HBV-endemic area.

METHODS

A total of 1950 consecutive patients newly diagnosed with HCC between 2002 and 2015 were included. Patient records were reviewed. We compared non-viral and non-alcoholic HCC patients with other etiological groups for HCC. In addition, we compared HCC patients with negative hepatitis B surface antigen (HBsAg) and positive anti-HBc to those with negative HBsAg and negative anti-HBc, and to those with HBV.

RESULTS

The prevalence of non-viral and non-alcoholic HCC increased from 7% in 2002-2011 to 12% in 2012-2015. The proportion of non-viral and non-alcoholic HCC gradually increased with age. Patients with non-viral and non-alcoholic HCC exhibited higher rates of metabolic disorders and preserved liver function. The rate of anti-HBc positivity was similarly high in all HCC etiological groups. The clinical features of HCC patients with negative HBsAg and positive anti-HBc were similar to those with negative HBsAg and negative anti-HBc, but significantly different from those with HBV HCC. Regarding tumor characteristics, patients in the non-viral and non-alcoholic HCC group had more advanced stages of tumors (mUICC stage III-V and BCLC stage C/D). There was no significant difference in overall survival among the patient groups. The presence of anti-HBc did not affect patient survival.

CONCLUSION

Patients with non-viral and non-alcoholic HCC had a relatively high prevalence of metabolic disorders and preserved liver function. However, they had advanced tumor stage compared to patients from other etiological groups. Anti-HBc positivity did not affect the clinical characteristics or prognosis of non-HBV HCC patients in this study.

Reactivation of Resolved Hepatitis B After Daratumumab for Multiple Myeloma

The risk of reactivation of resolved hepatitis B virus (HBV) in hepatitis B surface antigen (HBsAg)-negative multiple myeloma patients after daratumumab has not been reported. Among 93 patients with daratumumab treatment, reactivation occurred in 6 patients (6.5%) with one hepatic failure. This is the first report demonstrating a considerable risk of reactivation of resolved HBV after daratumumab.

Targeted Next-Generation Sequencing of Plasma Cell-Free DNA in Korean Patients with Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is the second-most-common cause of cancer-related deaths worldwide, and an accurate and non-invasive biomarker for the early detection and monitoring of HCC is required. We assessed pathogenic variants of HCC driver genes in cell-free DNA (cfDNA) from HCC patients who had not undergone systemic therapy.

Methods

Plasma cfDNA was collected from 20 HCC patients, and deep sequencing was performed using a customized cfDNA next-generation sequencing panel, targeting the major HCC driver genes (TP53, CTNNB1, TERT) that incorporates molecular barcoding.

Results

In 13/20 (65%) patients, we identified at least one pathogenic variant of two major HCC driver genes (TP53 and CTNNB1), including 16 variants of TP53 and nine variants of CTNNB1. The TP53 and CTNNB1 variants showed low allele frequencies, with median values of 0.17% (range 0.06%–6.99%) and 0.07% (range 0.05%–0.96%), respectively. However, the molecular coverage of variants was sufficient, with median values of 5,543 (range 2,317–9,088) and 7,568 (range 2,400–9,633) for TP53 and CTNNB1 variants, respectively.

Conclusions

Our targeted DNA sequencing successfully identified low-frequency pathogenic variants in the cfDNA from HCC patients by achieving high coverage of unique molecular families. Our results support the utility of cfDNA analysis to identify somatic gene variants in HCC patients.

Improving the Prediction of Relapse After Nucleos(t)ide Analogue Discontinuation in Patients With Chronic Hepatitis B

BACKGROUND

Current guidelines recommend rules for stopping nucleos(t)ide analogues (NAs) in patients with chronic hepatitis B (CHB), but off-therapy relapse is still high. This study aimed to identify predictors of off-therapy relapse and improve existing stopping rules.

METHODS

This retrospective study included 488 patients with CHB (262 hepatitis B e antigen [HBeAg]-positive and 226 HBeAg-negative) who discontinued NAs. Posttreatment relapse was investigated.

RESULTS

During the median follow-up period of 73.3 months, the cumulative 5-year and 10-year virologic relapse (VR) rates were 73.5% and 76.1%, respectively. In HBeAg-positive patients, end-of-therapy hepatitis B surface antigen (HBsAg) levels (hazard ratio [HR], 1.93 [95% confidence interval {CI}, 1.42-2.61]) and consolidation duration ≥2 years (HR, 0.31 [95% CI: .17-.58]) were independent predictors of VR. Consolidation ≥2 years and low HBsAg levels (≤560 IU/mL) significantly lowered VR rates. In HBeAg-negative patients, only the HBsAg level (HR, 1.61 [95% CI: 1.24-2.11]) was independently predictive of VR. Cirrhosis was significantly associated with higher VR rates in HBeAg-negative patients with low HBsAg levels (≤800 IU/mL). Combining end-of-therapy HBsAg levels with current stopping rules or consolidation duration further reduced off-therapy relapse, with 2-year VR rates of approximately 15%-25% in HBeAg-positive patients and 35% in HBeAg-negative patients.

CONCLUSIONS

End-of-therapy HBsAg levels, consolidation duration, and cirrhosis are key determinants of off-therapy relapse. Together with low HBsAg levels, extended consolidation therapy for ≥2 years should be ensured, and cirrhotic patients should continue NAs even if low HBsAg levels are achieved. A combination of these parameters will help identify individuals at low risk of relapse and significantly improve the predictive ability of the existing stopping rules.

Exosomal miR-125b Exerts Anti-Metastatic Properties and Predicts Early Metastasis of Hepatocellular Carcinoma

Background & Aims

Cancer metastasis is responsible for the majority of cancer-related deaths. Exosomal miRNAs have emerged as promising biomarkers for cancer, serving as signaling molecules that can regulate tumor growth and metastasis. This study examined circulating exosomal miRNAs that could predict hepatocellular carcinoma (HCC) metastasis.

Methods

Exosomal miRNA was measured by quantitative real-time PCR (qRT-PCR) in a large set of patients (n = 284). To investigate the role of exosomal miRNA in HCC, we performed a series of in vitro tests, such as exosome labeling, qRT-PCR, reverse transcription PCR, wound healing assay, transwell assay, and Western blot assay.

Results

Exosomal miR-125b was drastically downregulated in HCC patients with metastasis than in those without metastasis. In vitro, we observed the uptake of miR-125b by exosome in recipient cells. Exosome-mediated miR-125b significantly inhibited migration and invasion abilities and downregulated the mRNA expressions of MMP-2, MMP-9, and MMP-14 in recipient cells via intercellular communication. Further investigation revealed that miR-125b suppressed SMAD2 protein expression in recipient cells by binding to its 3' untranslated regions. Exosome-mediated miR-125b transfer also disrupted TGF-β1-induced epithelial-mesenchymal transition and TGF-β1/SMAD signaling pathway in recipient cells by leading to a decrease of SMAD2 protein expression. Moreover, exosomal miR-125b was downregulated after metastasis compared with that at baseline in patients with serial measurements before and after metastasis.

Conclusions

The results imply that exosome-mediated miR-125b exerts anti-metastatic properties in HCC. These findings highlight that circulating exosomal miR-125b might represent a reliable biomarker with diagnostic and therapeutic implications for extrahepatic metastasis from HCC.

Real-Life Experience of mTOR Inhibitors in Liver Transplant Recipients in a Region Where Living Donation Is Predominant

Background: Mammalian target of rapamycin (mTOR) inhibitors, such as everolimus and sirolimus, may be efficacious in preserving renal function in liver transplantation (LT) recipients while preventing hepatocellular carcinoma (HCC) recurrence.

Materials and Methods: In this study, we retrospectively evaluated the safety, efficacy, and renoprotective effects of mTOR inhibitors in LT recipients. Among the 84 patients enrolled, mTOR inhibitor was commenced during the first year after LT. Renal function was measured by estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease equation.

Results: Regarding the type of mTOR inhibitor, everolimus was used in 71 patients and sirolimus in 13 patients. Concomitant tacrolimus was used in 63 patients (75.0%). For total enrolled patients, kidney function did not significantly change during 12 months after initiation of mTOR inhibitors, although tacrolimus-withdrawn patients (n = 21) showed better kidney function compared to tacrolimus-minimized patients (n = 63) after conversion. However, a significant improvement in kidney function was observed in the eGFR <60 ml/min/1.73 m2 group (n = 19) 12 months after initiation of mTOR inhibitors, for both patient groups with early + mid starters (n = 7, stating within 1 year after LT) and late starters (n = 12, starting over 1 year after LT). mTOR inhibitors were safely administered without serious adverse events that led to drug discontinuation.

Conclusion: We demonstrated that patients with renal impairment showed significant improvement in renal function regardless of the timing of mTOR inhibitor start, suggesting that switch to mTOR inhibitors may be beneficial when renal function declines.

A new high-content screening assay of the entire hepatitis B virus life cycle identifies novel antivirals

Background & Aims

Chronic hepatitis B is an incurable disease. Addressing the unmet medical need for therapies has been hampered by a lack of suitable cell culture models to investigate the HBV life cycle in a single experimental setup. We sought to develop a platform suitable to investigate all aspects of the entire HBV life cycle.

Methods

HepG2-NTCPsec+ cells were inoculated with HBV. Supernatants of infected cells were transferred to naïve cells. Inhibition of infection was determined in primary and secondary infected cells by high-content imaging of viral and cellular factors. Novel antivirals were triaged in cells infected with cell culture- or patient-derived HBV and in stably virus replicating cells. HBV internalisation and target-based receptor binding assays were conducted.

Results

We developed an HBV platform, screened 2,102 drugs and bioactives, and identified 3 early and 38 late novel HBV life cycle inhibitors using infectious HBV genotype D. Two early inhibitors, pranlukast (EC₅₀ 4.3 μM; 50% cytotoxic concentration [CC₅₀] >50 μM) and cytochalasin D (EC₅₀ 0.07 μM; CC₅₀ >50 μM), and 2 late inhibitors, fludarabine (EC₅₀ 0.1 μM; CC₅₀ 13.4 μM) and dexmedetomidine (EC₅₀ 6.2 μM; CC₅₀ >50 μM), were further investigated. Pranlukast inhibited HBV preS1 binding, whereas cytochalasin D prevented the internalisation of HBV. Fludarabine inhibited the secretion of HBV progeny DNA, whereas dexmedetomidine interfered with the infectivity of HBV progeny. Patient-derived HBV genotype C was efficiently inhibited by fludarabine (EC₅₀ 0.08 μM) and dexmedetomidine (EC₅₀ 8.7 μM).

Conclusions

The newly developed high-content assay is suitable to screen large-scale drug libraries, enables monitoring of the entire HBV life cycle, and discriminates between inhibition of early and late viral life cycle events.

Lay summary

HBV infection is an incurable, chronic disease with few available treatments. Addressing this unmet medical need has been hampered by a lack of suitable cell culture models to study the entire viral life cycle in a single experimental setup. We developed an image-based approach suitable to screen large numbers of drugs, using a cell line that can be infected by HBV and produces large amounts of virus particles. By transferring viral supernatants from these infected cells to uninfected target cells, we could monitor the entire viral life cycle. We used this system to screen drug libraries and identified novel anti-HBV inhibitors that potently inhibit HBV in various phases of its life cycle. This assay will be an important new tool to study the HBV life cycle and accelerate the development of novel therapeutic strategies.

•

We developed a high-content screening assay suitable to monitor the entire HBV life cycle and eligible to discriminate between early and late viral life cycle inhibition.

•

We screened FDA-approved drugs and bioactives.

•

We confirmed antiviral activity in primary and secondary assays, using stably virus replicating cells and cell culture- and patient-derived HBV.

•

Novel HBV inhibitors prevent receptor binding, virus internalisation, replication, or egress of viral progeny.

Association of Prophylactic Anti-Hepatitis B Virus Therapy With Improved Long-term Survival in Patients With Hepatocellular Carcinoma Undergoing Transarterial Therapy

BACKGROUND

The effect of prophylactic antiviral therapy (AVT) on survival of patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains unknown. This study aimed to determine whether prophylactic AVT could improve long-term survival in patients undergoing transarterial chemotherapy (TAC).

METHODS

Between 2002 and 2016, 2860 newly diagnosed HBV-related patients with HCC treated with TAC were screened to analyze 2 groups based on prophylactic use of antivirals. Treatment effects were analyzed using propensity score (PS) matching (1:1) separately for the entire cohort and each subgroup. The primary endpoint was overall survival.

RESULTS

A total of 1547 patients met the inclusion criteria and 1084 were PS matched for the 2 groups. Median follow-up duration was 16.55 months. In the entire unmatched cohort, patients receiving prophylactic AVT survived significantly longer than those who did not. Among AVT-untreated patients, baseline high viremia and HBV reactivation during treatment were significantly associated with shorter survival. Regarding types of antivirals, survival was significantly longer for patients receiving high-potency antivirals than those receiving low-potency antivirals. Survival differed with antiviral response. In the PS-matched cohort, the prophylactic AVT group survived significantly longer than the nonprophylactic group, irrespective of viral status or tumor stage. Prophylactic AVT remained an independent factor for survival. The association of prophylactic AVT with decreased risk of mortality persisted in patient subgroups after adjusting for baseline risk factors. Sensitivity analyses also confirmed estimated treatment effects.

CONCLUSIONS

Prophylactic AVT is associated with significantly improved long-term survival among patients undergoing TAC. High-potency antivirals are indicated for this approach.Hepatitis B virus-associated morbidity is a well-known complication during transarterial chemotherapy (TAC). Our large-scale study demonstrated that prophylactic therapy with high-potency antivirals provides a significantly better survival in TAC-treated patients, irrespective of baseline viremia status or tumor stage.

Nardostachys jatamansi Root Extract Attenuates Tumor Progression in Hepatocellular Carcinoma via Inhibition of ERK/STAT3 Pathways

BACKGROUND/AIM

Hepatocellular carcinoma (HCC) is a highly prevalent disease and treatment is limited. Therefore, development of new therapeutic agents is urgent. The aim of this study was to investigate the in vitro and in vivo anti-cancer effects of Nardostachys jatamansi root extract (NJRE) against HCC and underlying mechanisms involved in such effects.

MATERIALS AND METHODS

Effects of NJRE on viability of HCC cell lines were determined by MTT analysis and annexin/PI apoptosis assays. Expression levels of proteins in MAPK and STAT3 pathways and caspase-3 and PARP after treatment with NJRE in HCC cell lines were determined by western blotting. In a syngeneic model using mouse HCC cells Hepa1-6, inhibition of tumor formation after oral administration of NJRE was determined and expression levels of phospho-ERK and phospho-STAT3 in liver tissues were analyzed by immunohistochemical staining.

RESULTS

NJRE reduced the activation of STAT3 by inhibiting the expression of ERK and finally attenuated the proliferation of HCC.

CONCLUSION

NJRE has anti-cancer effects against HCC. It has potential to be used in the treatment of human HCC.

Sustained off therapy response after peglyated interferon favours functional cure and no disease progression in chronic hepatitis B

BACKGROUND & AIMS

Nucleos(t)ide analogue (NA) therapy in chronic hepatitis B (CHB) patients reduces liver-related mortality. However, long-term outcomes after pegylated interferon (PEG-IFN) therapy remain to be elucidated. Therefore, we aimed to investigate the long-term effectiveness and clinical outcomes of PEG-IFN therapy.

METHODS

A total of 190 patients treated with PEG-IFN for CHB or compensated cirrhosis were consecutively enrolled between 2005 and 2014, and 122 patients who completed the treatment were analysed. The initial response was assessed at 6 months post-treatment and defined as achieving both <2000 IU/mL HBV DNA and HBeAg loss or seroconversion in the HBeAg-positive group, and <2000 IU/mL HBV DNA in the HBeAg-negative group. The rates of HBsAg loss, disease progression to cirrhosis or HCC, and sustained off-therapy response, defined as not requiring further NAs because of low viremia and liver enzymes, were analysed.

RESULTS

The median follow-up period was 7.2 years. Forty-three (35.2%) patients achieved an initial response and 53 patients (43.4%) achieved a sustained response. Initial responders displayed higher rates of sustained response than noninitial responders (69.6% vs 32.5%, P < .001). A higher rate of HBsAg loss was observed in patients who achieved a sustained response than in non-sustained responders (16.2% vs 2.5%, P = .01). Disease progression to cirrhosis or HCC was observed in eight patients (6.6%) who were nonsustained responders.

CONCLUSIONS

During long-term follow-up after PEG-IFN treatment, nearly half of patients achieved sustained response without the need of further NA and these patients displayed favourable outcomes, including HBsAg loss and no disease progression.

HBV-Induced Increased N6 Methyladenosine Modification of PTEN RNA Affects Innate Immunity and Contributes to HCC

BACKGROUND AND AIMS

Epitranscriptomic modification of RNA has emerged as the most prevalent form of regulation of gene expression that affects development, differentiation, metabolism, viral infections, and most notably cancer. We have previously shown that hepatitis B virus (HBV) transcripts are modified by N6 methyladenosine (m⁶ A) addition. HBV also affects m⁶ A modification of several host RNAs, including phosphatase and tensin homolog (PTEN), a well-known tumor suppressor. PTEN plays a critical role in antiviral innate immunity and the development of hepatocellular carcinoma (HCC). Reports have shown that PTEN controlled interferon regulatory factor 3 (IRF-3) nuclear localization by negative phosphorylation of IRF-3 at Ser97, and PTEN reduced carcinogenesis by inhibiting the phosphatidylinositol-3-kinase (PI3K)/AKT pathway.

APPROACH AND RESULTS

Here, we show that HBV significantly increases the m⁶ A modification of PTEN RNA, which contributes to its instability with a corresponding decrease in PTEN protein levels. This is reversed in cells in which the expression of m⁶ A methyltransferases is silenced. PTEN expression directly increases activated IRF-3 nuclear import and subsequent interferon synthesis. In the absence of PTEN, IRF-3 dephosphorylation at the Ser97 site is decreased and interferon synthesis is crippled. In chronic HBV patient biopsy samples, m⁶ A-modified PTEN mRNA levels were uniformly up-regulated with a concomitant decrease of PTEN mRNA levels. HBV gene expression also activated the PI3K/AKT pathway by regulating PTEN mRNA stability in HCC cell lines.

CONCLUSIONS

The m⁶ A epitranscriptomic regulation of PTEN by HBV affects innate immunity by inhibiting IRF-3 nuclear import and the development of HCC by activating the PI3K/AKT pathway. Our studies collectively provide new insights into the mechanisms of HBV-directed immune evasion and HBV-associated hepatocarcinogenesis through m⁶ A modification of the host PTEN mRNAs.

Sorafenib for advanced hepatocellular carcinoma provides better prognosis after liver transplantation than without liver transplantation

BACKGROUND

Although sorafenib has been used to treat advanced hepatocellular carcinoma (HCC), the efficacy of sorafenib in patients with recurrent HCCs after liver transplantation (LT) has not been compared with that in patients without LT (non-LT).

METHODS

Between 2008 and 2019, a total of 832 consecutive HCC patients treated with sorafenib (790 in the non-LT group and 42 in the LT group) were enrolled. The primary outcome was overall survival (OS). Secondary outcomes were time-to-progression (TTP), objective response rate (ORR) and disease control rate (DCR). Treatment outcomes were assessed by multiple subgroup analyses and propensity-score matching (PSM).

RESULTS

The median follow-up duration was 152.5 days. The LT group was younger and had smaller intrahepatic HCC than the non-LT group. The LT group showed significantly better OS (16.8 vs. 7.1 months, p < 0.001), TTP, ORR and DCR than the non-LT group. The superior efficacy of sorafenib in the LT group was corroborated in multiple subgroup analyses stratified by metastasis, effective sorafenib maintenance dose, or Child-Turcotte-Pugh class A. LT was identified as an independent factor for favorable OS. Intrahepatic HCC was the strongest tumor-related factor for both OS and TTP and was significantly associated with tumor response and hepatic function. Finally, subanalyses including only patients with small intrahepatic HCC or PSM modeling showed no difference in sorafenib efficacy between the LT and the non-LT groups.

CONCLUSION

Sorafenib provides better outcomes in the LT setting than the non-LT setting. This benefit may be associated with the smaller intrahepatic HCC coupled with preserved hepatic function in LT recipients.

Continuing besifovir dipivoxil maleate versus switching from tenofovir disoproxil fumarate for treatment of chronic hepatitis B: Results of 192-week phase 3 trial

Background/Aims

Besifovir dipivoxil maleate (BSV), an acyclic nucleotide phosphonate, shows potent antiviral activity against hepatitis B virus. Our previous 48-week trial revealed that BSV has comparable antiviral efficacy to tenofovir disoproxil fumarate (TDF) and better safety profiles in terms of improved renal and bone safety. This extension study evaluated the prolonged efficacy and safety of BSV in treatment-naive chronic hepatitis B patients.

Methods

Patients continued to participate in an open-label BSV study after an initial 48-week double-blind comparison of BSV and TDF treatment. The antiviral efficacy and drug safety was evaluated up to 192 weeks in two groups: patients continuing BSV treatment (BSV-BSV) and patients switching from TDF to BSV after 48 weeks (TDF-BSV).

Results

Among 197 patients receiving randomized treatments, 170 (86%) entered the open-label phase and 152 (77%) entered the 192-week extension study. Virological response rates over 192 weeks were 92.50% and 93.06% in the BSV-BSV and TDF-BSV groups, respectively (P=0.90). Hepatitis B envelop antigen seroconversion and alanine aminotransferase normalization rates were similar between the groups (P=0.75 and P=0.36, respectively). There were no drug-resistant mutations to BSV. Bone mineral density and renal function were well preserved in the BSV-BSV group, whereas these initially worsened then recovered after switching therapy in the TDF-BSV group.

Conclusions

BSV maintained potent antiviral efficacy after 192 weeks and showed no evidence of drug resistance. BSV was safe, well tolerated, and effective in patients who switched from TDF to BSV. Trial Registration Number: NCT01937806 (date: 10 Sep 2013).

Combination Treatment With Metformin and Tacrolimus Improves Systemic Immune Cellular Homeostasis by Modulating Treg and Th17 Imbalance

We examined the effect of combination therapy with metformin and tacrolimus on immune parameters including T regulatory (Treg) and type 17 helper T (Th17) cells in vitro and in vivo in mice and in liver transplantation (LT) patients. T cell proliferation and subtypes after in vitro T cell activation or allogeneic stimulation were evaluated. RNA sequencing and microarray analysis were used to evaluate differences in gene expression. Metformin and tacrolimus were administered to mice with graft-versus-host disease (GVHD) and the effects in vivo were assessed. Five LT patients were treated with metformin and the changes in Treg and Th17 cells examined. Combination therapy decreased Type 1 helper T (Th1) and Th17 cells present after in vitro T cell activation, whereas genes associated with Treg were overexpressed. During in vitro allogeneic stimulation, combination therapy increased Treg cells and decreased T cell proliferation and pro-inflammatory markers. In mice with GVHD, combination treatment decreased the clinical and pathological severity of GVHD. In LT patients, addition of metformin increased the peripheral percentage of CD4+Treg and CD8+Treg cells and decreased CD4+Th17. Our study suggests that the addition of metformin to tacrolimus may improve immunological balance by increasing Treg cells and decreasing Th17 cells.

Persistence of intrahepatic hepatitis B virus DNA integration in patients developing hepatocellular carcinoma after hepatitis B surface antigen seroclearance

Background/Aims

The role of hepatitis B virus (HBV) integration into the host genome in hepatocarcinogenesis following hepatitis B surface antigen (HBsAg) seroclearance remains unknown. Our study aimed to investigate and characterize HBV integration events in chronic hepatitis B (CHB) patients who developed hepatocellular carcinoma (HCC) after HBsAg seroclearance.

Methods

Using probe-based HBV capturing followed by next-generation sequencing technology, HBV integration was examined in 10 samples (seven tumors and three non-tumor tissues) from seven chronic carriers who developed HCC after HBsAg loss. Genomic locations and patterns of HBV integration were investigated.

Results

HBV integration was observed in six patients (85.7%) and eight (80.0%) of 10 tested samples. HBV integration breakpoints were detected in all of the non-tumor (3/3, 100%) and five of the seven (71.4%) tumor samples, with an average number of breakpoints of 4.00 and 2.43, respectively. Despite the lower total number of tumoral integration breakpoints, HBV integration sites in the tumors were more enriched within the genic area. In contrast, non-tumor tissues more often showed intergenic integration. Regarding functions of the affected genes, tumoral genes with HBV integration were mostly associated with carcinogenesis. At enrollment, patients who did not remain under regular HCC surveillance after HBsAg seroclearance had a large HCC, while those on regular surveillance had a small HCC.

Conclusions

The biological functions of HBV integration are almost comparable between HBsAg-positive and HBsAg-serocleared HCCs, with continuing pro-oncogenic effects of HBV integration. Thus, ongoing HCC surveillance and clinical management should continue even after HBsAg seroclearance in patients with CHB.

Obesity and the risk of primary liver cancer: A systematic review and meta-analysis

Background/Aims

In this systematic review and meta-analysis, we aimed to clarify the effect of obesity on the occurrence of and mortality from primary liver cancer.

Methods

This study was conducted using a systematic literature search of MEDLINE, EMBASE, and the Cochrane Library until November 2018 using the primary keywords “obesity,” “overweight,” “body mass index (BMI),” “body weight,” “liver,” “cancer,” “hepatocellular carcinoma,” “liver cancer,” “risk,” and “mortality.” Studies assessing the relationship between BMI and occurrence of or mortality from primary liver cancer in prospective cohorts and those reporting hazard ratios (HRs) or data that allow HR estimation were included.

Results

A total of 28 prospective cohort studies with 8,135,906 subjects were included in the final analysis. These included 22 studies with 6,059,561 subjects for cancer occurrence and seven studies with 2,077,425 subjects for cancer-related mortality. In the meta-analysis, an increase in BMI was associated with the occurrence of primary liver cancer (HR, 1.69; 95% confidence interval, 1.50–1.90, I²=56%). A BMI-dependent increase in the risk of occurrence of primary liver cancer was reported. HRs were 1.36 (95% CI, 1.02–1.81), 1.77 (95% CI, 1.56–2.01), and 3.08 (95% CI, 1.21–7.86) for BMI >25 kg/m², >30 kg/m², and >35 kg/m², respectively. Furthermore, increased BMI resulted in enhanced liver cancer-related mortality (HR, 1.61; 95% CI, 1.14–2.27, I²=80%).

Conclusions

High BMI increases liver cancer mortality and occurrence of primary liver cancer. Obesity is an independent risk factor for the occurrence of and mortality from primary liver cancer.

Diffusion-Weighted Magnetic Resonance Imaging in Hepatocellular Carcinoma as a Predictor of a Response to Cisplatin-Based Hepatic Arterial Infusion Chemotherapy

This study aimed to identify the utility of diffusion-weighted magnetic resonance (MR) imaging with an apparent diffusion coefficient (ADC) map as a predictor of the response of hepatocellular carcinoma (HCC) to cisplatin-based hepatic arterial infusion chemotherapy (HAIC). We retrospectively evaluated 113 consecutive patients with Barcelona Clinical Liver Cancer (BCLC) stage B or C HCC, who underwent gadoxetic acid-enhanced and diffusion-weighted MR imaging. The appropriate cutoff for the pretreatment tumor-to-liver ADC ratio was determined to be 0.741. Of the 113 patients, 50 (44%) presented with a pretreatment tumor-to-liver ADC ratio < 0.741 (low group). Evaluation of the treatment response after 2-3 cycles of HAIC in these 50 patients revealed that 21 patients (42%) experienced an objective response to HAIC. On the other hand, only 11 of the 63 patients (17%) with a pretreatment tumor-to-liver ADC ratio ≥ 0.741 (high group) showed an objective response. Thus, the objective response rate was significantly higher in the low group than in the high group (P = 0.006). Multivariate logistic regression analysis using parameters including perfusion alteration, percentage of non-enhancing portions, and pretreatment tumor-to-liver ADC ratio revealed that a pretreatment tumor-to-liver ADC ratio < 0.741 (odds ratio 3.217; P = 0.014) was the sole predictor of an objective response to HAIC. Overall survival rates were significantly higher in patients with objective responses to HAIC than in those without objective responses (P = 0.001 by log-rank test). In conclusion, patients with BCLC stage C or C HCC with a pretreatment tumor-to-liver ADC ratio < 0.741 showed a favorable intrahepatic response to cisplatin-based HAIC. Therefore, diffusion-weighted MR imaging can play a critical role as a predictor of response to cisplatin-based HAIC in unresectable HCC.

EpCAM-high liver cancer stem cells resist natural killer cell-mediated cytotoxicity by upregulating CEACAM1

Background

Natural killer (NK) cells can recognize and kill cancer cells directly, but their activity can be attenuated by various inhibitory molecules expressed on the surface. The expression of epithelial cell adhesion molecule (EpCAM), a potential marker for cancer stem cells (CSCs), is known to be strongly associated with poor clinical outcomes in hepatocellular carcinoma (HCC). NK cells targeting CSCs may be a promising strategy for anti-tumor therapy, but little is known about how they respond to EpCAM^high CSCs in HCC.

Methods

EpCAM expression was assessed by immunohistochemistry in 280 human HCC tissues obtained from curative surgery. To investigate the functional activity of NK cells against liver CSCs, EpCAM^high and EpCAM^low Huh-7 cells were sorted by flow cytometry. The functional role of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), which is related to NK cells, was determined by in vitro co-culture of NK cells and hepatoma cells using Hepa1–6 mouse hepatoma cells, as well as in vivo experiments using C57/BL6 mice.

Results

The frequency of recurrence after curative surgery was higher in patients with positive EpCAM expression than in those with negative EpCAM expression. In subsequent analysis based on the anatomical location of EpCAM expression, patients with peritumoral EpCAM expression showed worse prognosis than those with pantumoral EpCAM expression. Co-culture experiments demonstrated that CEACAM1 was upregulated on the surface of EpCAM^high HCC cells, resulting in resistance to NK cell-mediated cytotoxicity. Inversely, silencing CEACAM1 restored cytotoxicity of NK cells against EpCAM^high Huh-7 cells. Moreover, neutralizing CEACAM1 on the NK cell surface enhanced killing of Huh-7 cells, suggesting that homophilic interaction of CEACAM1 is responsible for attenuated NK cell–mediated killing of CEACAM1^high cells. In mouse experiments with Hepa1–6 cells, EpCAM^high Hepa1–6 cells formed larger tumors and showed higher CEACAM1 expression after NK cell depletion. NK-mediated cytotoxicity was enhanced after blocking CEACAM1 expression using the anti-CEACAM1 antibody, thereby facilitating tumor regression. Moreover, CEACAM1 expression positively correlated with EpCAM expression in human HCC tissues, and serum CEACAM1 levels were also significantly higher in patients with EpCAM⁺ HCC.

Conclusion

Our data demonstrated that EpCAM^high liver CSCs resist NK cell–mediated cytotoxicity by upregulation of CEACAM1 expression.

Infiltration of T Cells and Programmed Cell Death Ligand 1-expressing Macrophages as a Potential Predictor of Lenvatinib Response in Hepatocellular Carcinoma

Background/Aims

Lenvatinib was recently proven to be non-inferior to sorafenib in treating unresectable hepatocellular carcinoma (HCC) in a phase-3 randomized controlled trial. In this study, we investigated whether the response to lenvatinib was affected by tumor immunogenicity.

Methods

Between May 2019 and April 2020, nine patients with intermediate-to-advanced HCC, who were treated with lenvatinib after liver biopsy, were enrolled. Immunohistochemical staining and multi-color flow cytometry were performed on specimens obtained from liver biopsy.

Results

Among the nine patients enrolled, four showed objective responses (complete responses+partial responses). Immunohistochemical staining for CD3, CD68, and programmed cell death ligand 1 (PD-L1) demonstrated that patients with objective responses showed marked infiltration of T cells and PD-L1-expressing macrophages in intra-tumoral and peri-tumoral tissues compared to those without objective responses. A significant difference in the numbers of infiltrated T cells, both in the intra-tumoral (P<0.01) and peri-tumoral regions (P<0.05), were identified between responders and non-responders. Regarding the number of infiltrated macrophages, no significant difference was found between the responders and non-responders, although the number of PD-L1-expressing tumor-associated macrophages was significantly higher in responders than that in non-responders (P<0.05).

Conclusions

Tumor immunogenicity, as indicated by T cell and PD-L1-positive macrophage infiltration, affects lenvatinib response in unresectable HCC.

A Simple and Cost-Effective DNA Preparation Method Suitable for High-Throughput PCR Quantification of Hepatitis B Virus Genomes

Hepatitis B virus (HBV) is a para-retrovirus that reverse transcribes its pregenomic RNA into relaxed circular DNA inside viral nucleocapsids. The number of HBV genomes produced in vitro is typically quantified using commercial silica-membrane-based nucleic acid purification kits to isolate total DNA followed by HBV-specific quantitative PCR (qPCR). However, despite the convenience of commercial kits, this procedure is costly and time-consuming due to multiple centrifugation steps, which produce unnecessary waste. Here, we report a rapid, cost-effective, and environmentally friendly total DNA preparation method. The assay is based on the simple incubation of detergent and proteinase K with cells or cell-free supernatants to permeabilize cells and disrupt viral particles. After heat inactivation and subsequent centrifugation to clear the lysates, DNA samples are directly subjected to qPCR to quantify HBV genomes. As a proof of concept, the assay was developed in 12-well plates to assess intra- and extracellular HBV genome equivalents (GEqs) of stably viral-replicating cell lines (e.g., HepAD38) and HBV-infected HepG2-NTCP cells, both treated with lamivudine (LMV), an HBV replication inhibitor. Viral DNA was also prepared from the serum of patients chronically infected with HBV. To validate the assay, a representative commercial DNA isolation kit was used side-by-side to isolate intra- and extracellular HBV DNA. Both methods yielded comparable amounts of HBV GEqs with comparable LMV 50% efficient concentration (EC₅₀) values. The assay was subsequently adapted to 96- and 384-well microtiter plates using HepAD38 cells. The EC₅₀ values were comparable to those obtained in 12-well plates. In addition, the calculated coefficient of variation, Z’ values, and assay window demonstrated high reproducibility and quality. We devised a novel, robust, reproducible, high-throughput microtiter plate DNA preparation method suitable for quantifying HBV GEqs by qPCR analysis. This strategy enables rapid and convenient quantitative analysis of multiple viral DNA samples in parallel to investigate intracellular HBV replication and the secretion of DNA-containing viral particles.