USO1 isoforms differentially promote liver cancer progression by dysregulating the ER-Golgi network.

Alternative splicing of RNA transcripts plays an important role in cancer development and progression. Recent advances in RNA-seq technology have made it possible to identify alternately spliced events in various types of cancer; however, research on hepatocellular carcinoma (HCC) is still limited. Here, by performing RNA-seq profiling of HCC transcripts at isoform level, we identified tumor-specific and molecular subtype-dependent expression of the USO1 isoforms, which we designated as a normal form USO1-N (XM_001290049) and a tumor form USO1-T (NM_003715). The expression of USO1-T, but not USO1-N, was associated with worse prognostic outcomes of HCC patients. We confirmed that the expression of USO1-T promoted an aggressive phenotype of HCC, both in vitro and in vivo. In addition, structural modeling analyses revealed that USO1-T lacks an ARM10 loop encoded by exon 15, which may weaken the dimerization of USO1 and its tethering to GM130. We demonstrated that USO1-T ensured unstacking of the Golgi and accelerated the vesicles trafficking from endoplasmic reticulum (ER) to Golgi and plasma membrane in multiple liver cancer cells. ERK and GRASP65 were found to be involved in the USO1-T-mediated Golgi dysfunction. Conclusively, we provide new mechanophysical insights into the USO1 isoforms that differentially regulate the ER-Golgi network, promoting the heterogeneous HCC progression.

Risk Factors for Beyond Milan Recurrence After Hepatic Resection for Single Hepatocellular Carcinoma No Larger Than 5 Centimeters.

Hepatic resection (HR) is considered a treatment of choice for a single hepatocellular carcinoma (HCC) ≤5 cm in patients with preserved liver function. However, it is possible for these patients to develop a severe form of recurrence (beyond Milan recurrence [BMR] criteria). This recurrence could have been avoided if liver transplantation (LT) was performed primarily, as LT is believed to yield a more favorable oncological outcome compared with HR. The aim of this study was to determine the risk factors for BMR after HR and to verify whether primary LT can provide a more favorable outcome in patients with BMR risk factors. Data from 493 patients who underwent HR for HCC ≤5 cm between 1995 and 2016 were analyzed. Among them, 74 patients (15%) experienced BMR. The 10-year survival rate of patients with BMR was significantly low compared with that of patients without BMR (22.6% versus 79.8%; P < 0.01). In multivariate analysis, calculated hepatic venous pressure gradient ≥7 mm Hg and microvascular invasion were identified as the risk factors for BMR (P < 0.05). During the same period, 63 eligible patients underwent LT as a primary treatment for HCC ≤5 cm. No significant difference in long-term survival rate was observed when no risk factor for BMR was present in the HR and LT groups (85.5% versus 100%; P = 0.39). However, 10-year survival was poorer in the HR group in the presence of risk factors for BMR (60.6% versus 91.8%; P < 0.001). Among the patients with HCCs ≤5 cm, which are resectable and transplantable, LT is indicated when calculated hepatic venous pressure gradient ≥7 mm Hg and/or microvascular invasion is present.

TPRG1-AS1 induces RBM24 expression and inhibits liver cancer progression by sponging miR-4691-5p and miR-3659.

BACKGROUND & AIMS: Noncoding RNAs (ncRNAs) play critical roles in hepatocellular carcinoma (HCC) progression. Here, by performing RNA-sequencing (RNA-Seq) profiling, we sought to identify novel ncRNAs that potentially drive the heterogeneous progression of liver cancers. METHODS: RNA-Seq profiles were obtained from 68 HCC specimens and 10 samples of adjacent non-tumour liver tissues. The functional significance of the potential driver ncRNAs was evaluated by cell experiments. RESULTS: TPRG1-AS1 was identified as a potential driver noncoding RNA that promotes heterogeneous liver cancer progression. TPRG1-AS1 induced tumour suppressor RNA-binding motif protein 24 (RBM24), suppressing tumour growth by activating apoptotic tumour cell death. In addition, we report that TPRG1-AS1 acts as a competing endogenous RNA (ceRNA) for RBM24, sponging miR-4691-5p and miR-3659 to interfere with their binding to RBM24. CONCLUSIONS: We suggest that TPRG1-AS1 is a novel ceRNA sponging miR-4691-5p and miR-3659, resulting in RBM24 expression and suppression of liver cancer growth. Our results provide new insights into the functions of ncRNAs in heterogeneous HCC progression.

Surgical Outcomes of Hepatocellular Carcinoma With Bile Duct Tumor Thrombus: A Korea-Japan Multicenter Study.

OBJECTIVE: To identify optimal surgical methods and the risk factors for long-term survival in patients with hepatocellular carcinoma accompanied by macroscopic bile duct tumor thrombus (BDTT). SUMMARY BACKGROUND DATA: Prognoses of patients with hepatocellular carcinoma accompanied by BDTT have been known to be poor. There have been significant controversies regarding optimal surgical approaches and risk factors because of the low incidence and small number of cases in previous reports. METHODS: Records of 257 patients from 32 centers in Korea and Japan (1992-2014) were analyzed for overall survival and recurrence rate using the Cox proportional hazard model. RESULTS: Curative surgery was performed in 244 (94.9%) patients with an operative mortality of 5.1%. Overall survival and recurrence rate at 5 years was 43.6% and 74.2%, respectively. TNM Stage (P < 0.001) and the presence of fibrosis/cirrhosis (P = 0.002) were independent predictors of long-term survival in the Cox proportional hazards regression model. Both performing liver resection equal to or greater than hemihepatectomy and combined bile duct resection significantly increased overall survival [hazard ratio, HR = 0.61 (0.38-0.99); P = 0.044 and HR = 0.51 (0.31-0.84); P = 0.008, respectively] and decreased recurrence rate [HR = 0.59 (0.38-0.91); P = 0.018 and HR = 0.61 (0.42-0.89); P = 0.009, respectively]. CONCLUSIONS: Clinical outcomes were mostly influenced by tumor stage and underlying liver function, and the impact of BDTT to survival seemed less prominent than vascular invasion. Therefore, an aggressive surgical approach, including major liver resection combined with bile duct resection, to increase the chance of R0 resection is strongly recommended.

HDAC6 Suppresses Let-7i-5p to Elicit TSP1/CD47-Mediated Anti-Tumorigenesis and Phagocytosis of Hepatocellular Carcinoma.

Histone deacetylase 6 (HDAC6) uniquely serves as a tumor suppressor in hepatocellular carcinogenesis, but the underlying mechanisms leading to tumor suppression are not fully understood. To identify comprehensive microRNAs (miRNAs) regulated by HDAC6 in hepatocellular carcinogenesis, differential miRNA expression analysis of HDAC6-transfected Hep3B cells was performed. Using integrative analyses of publicly available transcriptome data and miRNA target prediction, we selected five candidate miRNAs and, through in vitro functional validation, showed that let-7i-5p specifically suppressed thrombospondin-1 (TSP1) in hepatocellular carcinoma (HCC). Ectopic expression of antisense let-7i-5p (AS-let-7i-5p) inhibited in vitro tumorigenesis of HCC cells. In addition, treatments of partially purified TSP1 from culture cell media (ppTSP1) and recombinant TSP1 (rTSP1) exhibited similar effects with AS-let-7i-5p treatment on the same HCC cells, whereas TSP1 neutralizing antibody treatment significantly attenuated these effects. Notably, treatments of HDAC6 plasmid, AS-let-7i-5p, ppTSP1, and rTSP1 significantly suppressed in vitro angiogenesis and metastatic potential of HCC cells, but the co-treatment of TSP1 antibody specific to cluster of differentiation 47 (CD47) binding domain successfully blocked these effects in the same cells. Furthermore, we demonstrated that recovery of HDAC6 elicited let-7i-5p suppression to de-repress TSP1 expression; therefore, it occupied the CD47 receptor to block CD47-SIRPα-mediated anti-phagocytosis of macrophage in HCC. We also observed that HCC-derived exosomal let-7i-5p suppressed TSP1 of recipient hepatocyte cells. Treatments of HDAC6 plasmid, AS-let-7i-5p, and rTSP1 suppressed tumor incidence as well as tumor growth rates in a spontaneous mouse HCC model. Conclusion: Our findings suggest that the HDAC6-let-7i-5p-TSP1 regulatory pathway suppresses neoplastic and antiphagocytic behaviors of HCC by interacting with cell surface receptor CD47 in HCC and neighboring cells of tumor microenvironment, providing a therapeutic target for the treatment of liver malignancy and metastasis.

A Model to Predict 1-Month Risk of Transplant or Death in Hepatitis A-Related Acute Liver Failure.

Acute liver failure (ALF) caused by hepatitis A is a rare but fatal disease. Here, we developed a model to predict outcome in patients with ALF caused by hepatitis A. The derivation set consisted of 294 patients diagnosed with hepatitis A-related ALF (ALFA) from Korea, and a validation set of 56 patients from Japan, India, and United Kingdom. Using a multivariate proportional hazard model, a risk-prediction model (ALFA score) consisting of age, international normalized ratio, bilirubin, ammonia, creatinine, and hemoglobin levels acquired on the day of ALF diagnosis was developed. The ALFA score showed the highest discrimination in the prediction of liver transplant or death at 1 month (c-statistic, 0.87; 95% confidence interval [CI], 0.84-0.92) versus King's College criteria (KCC; c-statistic, 0.56; 95% CI, 0.53-0.59), U.S. Acute Liver Failure Study Group index specific for hepatitis A virus (HAV-ALFSG; c-statistic, 0.70; 95% CI, 0.65-0.76), the new ALFSG index (c-statistic, 0.79; 95% CI, 0.74-0.84), Model for End-Stage Liver Disease (MELD; c-statistic, 0.79; 95% CI, 0.74-0.84), and MELD including sodium (MELD-Na; c-statistic, 0.78; 95% CI, 0.73-0.84) in the derivation set (all P < 0.01). In the validation set, the performance of the ALFA score (c-statistic, 0.84; 95% CI, 0.74-0.94) was significantly better than that of KCC (c-statistic, 0.65; 95% CI, 0.52-0.79), MELD (c-statistic, 0.74; 95% CI, 0.61-0.87), and MELD-Na (c-statistic, 0.72; 95% CI, 0.58-0.85) (all P < 0.05), and better, but not statistically significant, than that of the HAV-ALFSG (c-statistic, 0.76; 95% CI, 0.61-0.90; P = 0.28) and new ALFSG indices (c-statistic, 0.79; 95% CI, 0.65-0.93; P = 0.41). The model was well-calibrated in both sets. Conclusion: Our disease-specific score provides refined prediction of outcome in patients with ALF caused by hepatitis A.

Prognostic Analysis of Hepatocellular Carcinoma With Hepatitis C Virus Infection Using Epithelial-Mesenchymal Transition Gene Profiles.

BACKGROUND: Epithelial-mesenchymal transition genes have prognostic influence on hepatocellular carcinoma (HCC). Previously, the following four epithelial-mesenchymal transition-related genes were considered to be significantly influential: E-cadherin (CDH1), inhibitor of DNA binding 2 (ID2), matrix metalloproteinase 9 (MMP9), and transcription factor 3 (TCF3). A prognostic prediction model, NRISK4 = (-0.333 × [CDH1] - 0.400 × [ID2] + 0.339 × [MMP9] + 0.387 × [TCF3]) was constructed, but from patients with HCC with predominantly hepatitis B virus infection. We therefore aim to validate if this model also fits patients with HCC and hepatitis C virus (HCV) infection. METHODS: We collected HCC tissue samples from 67 patients with HCV infection. Discrimination of the NRISK4 was re-estimated using receiver operating curve analysis and we redefined the appropriate cutoff value. Using this cutoff value, patients were divided into two groups (high/low risk patients) and we compared their clinicopathological factors and prognosis. RESULTS: Area under the curve of NRISK4 prediction was 0.70 and an appropriate cutoff value was 3.19 in this cohort. Patients were divided into high- (n = 25) and low-risk (n = 42) patients for prognosis. There were no significant differences in tumor factors between the two groups. Cancer-specific survival rates at 5 y after surgery on high- and low-risk patients were 45% and 68%, respectively (P = 0.02). At 2 y after surgery, recurrence rates were 68% and 37% among high- and low-risk patients, respectively (P = 0.01). Aggressive recurrences were highly observed in the high-risk patients (P = 0.01). CONCLUSIONS: NRISK4 model could also successfully validate prognosis of patients with HCC with HCV infection similarly to in the previous report of patients with hepatitis B virus infection, especially in the early period after surgery.

Hepatitis B Prophylaxis after Liver Transplantation in Korea: Analysis of the KOTRY Database.

BACKGROUND: Prophylaxis for hepatitis B virus (HBV) recurrence is essential after liver transplantation (LT) in HBV-associated recipients. We conducted real-world analysis of HBV prophylaxis after LT in the Korean population. METHODS: Korean Organ Transplantation Registry (KOTRY) database and additionally collected data (n = 326) were analyzed with special reference to types of HBV prophylaxis. RESULTS: The study cohort comprised 267 cases of living-donor LT and 59 cases of deceased-donor LT. Hepatocellular carcinoma (HCC) was diagnosed in 232 (71.2%) of these subjects. Antiviral agents were used in 255 patients (78.2%) prior to LT. HBV DNA was undetectable in 69 cases (21.2%) and detectable over wide concentrations in the other 257 patients (78.8%) prior to LT. Polymerase chain reaction analysis of the store blood samples detected HBV DNA in all patients, with 159 patients (48.9%) showing concentrations > 100 IU/mL. Post-transplant HBV regimens during the first year included combination therapy in 196 (60.1%), hepatitis B immunoglobulin (HBIG) monotherapy in 121 (37.1%), and antiviral monotherapy in 9 (2.8%). In the second post-transplant year, these regimens had changed to combination therapy in 187 (57.4%), HBIG monotherapy in 112 (34.4%), and antiviral monotherapy in 27 (8.3%). Trough antibody to hepatitis B surface antigen titers > 500 IU/mL and >1,000 IU/mL were observed in 61.7% and 25.2%, respectively. The mean simulative half-life of HBIG was 21.6 ± 4.3 days with a median 17.7 days. Up to 2-year follow-up period, HCC recurrence and HBV recurrence developed in 18 (5.5%) and 6 (1.8%), respectively. HCC recurrence developed in 3 of 6 patients with HBV recurrence. CONCLUSION: Combination therapy is the mainstay of HBV prophylaxis protocols in a majority of Korean LT centers, but HBIG was often administered excessively. Individualized optimization of HBIG treatments using SHL is necessary to adjust the HBIG infusion interval.

Longterm Analysis of Biliary Complications After Duct-to-Duct Biliary Reconstruction in Living Donor Liver Transplantations.

Biliary complication (BC) is still regarded as the Achilles' heel of a living donor liver transplantation (LDLT). This study aims to evaluate the longterm outcomes of the duct-to-duct (DD) biliary reconstruction using 7-0 suture and to identify the risk factors of BCs after LDLTs. Data of 140 LDLTs between 2006 and 2015 were analyzed. All biliary reconstructions were performed as DD anastomoses using 7-0 suture: 102 for the right lobe, 20 for the left lobe, and 18 for right posterior sector grafts. BC was defined as a bile leakage (BL) or a biliary stricture (BS), and the median follow-up time after LDLT was 65 months. A total of 19 recipients (13.5%) developed BCs (8 BLs and 16 BSs) after LDLT. The survival rates between recipients with and without BCs were 83% and 86.7%, respectively (P = 0.88). In univariate analyses, the risk factors for BC were small diameter of the graft's bile duct, long warm ischemic time, small graft-to-recipient weight ratio, and no use of external biliary stent (EBS). The graft's bile duct diameter ≤ 3 mm and no use of EBS were determined as independent risk factors (hazard ratios of 9.74 and 7.68, respectively) in multivariate analyses. The 116 recipients with EBS had no BL, 11 had BSs (9%), while 24 without EBS had 8 BLs (33%) and 5 BSs (21%). After a propensity score match between the recipients with and without EBS, the EBS group (24) developed only 1 BS (4%). In conclusion, DD anastomosis using 7-0 suture combined with EBS could provide favorable longterm outcomes after LDLT, which should thus be considered the surgical technique of choice for LDLTs.

Prognostic Prediction Models for Resection of Large Hepatocellular Carcinoma: A Korean Multicenter Study.

BACKGROUND: We developed a prognostic prediction model (PPM) using 4 factors for hepatic resection (HR) of large hepatic cellular carcinoma (HCC). Multiplication of α-fetoprotein (AFP), des-γ-carboxy prothrombin, and tumor volume (TV) (ADV score) is a surrogate marker for post-resection prognosis. This study intended to validate the predictive power of 4-factor PPM and to develop new ADV score-based PPM. METHODS: A total of 526 patients who underwent HR for solitary HCC ≥ 8 cm were selected from 9 Korean institutions between 2008 and 2014. RESULTS: Median tumor diameter and TV were 11.0 cm and 398 mL, respectively. Tumor recurrence and patient survival rates were 53.0 and 78.4% at 1 year and 70.2 and 49.3% at 5 years, respectively. Independent risk factors for both tumor recurrence and patient survival included AFP ≥ 100 ng/mL, hypermetabolic FDG-positron emission tomography (PET), microvascular invasion and satellite nodules, which comprised 4 factors of the PPM. Five subgroups based on the number of involved risk factors exhibited significant differences in tumor recurrence and patient survival. ADV score cutoff was set at 7log (ADV7log) after cluster prognostic analysis. Patient grouping according to combination of ADV7log and FDG-PET findings (ADV7log-PET) exhibited significant differences in tumor recurrence and patient survival, comparable to those of the 4-factor PPM. CONCLUSIONS: Two PPMs using 4 risk factors and ADV7log-PET could reliably predict the risk of early HCC recurrence and long-term survival outcomes in patients who underwent HR for large HCC. We believe that these PPMs can guide surgical treatment for large HCCs from preoperative HR planning to post-resection follow-up.

Plugged percutaneous biopsy of the liver in living-donor liver transplantation recipients suspected to have graft rejection.

Background Percutaneous biopsy is a widely-accepted technique for acquiring histologic samples of the liver. When there is concern for bleeding, plugged percutaneous biopsy (PPB) may be performed, which involves embolization of the biopsy tract. Purpose To evaluate the efficacy and safety of PPB of the liver in patients suspected to have graft rejection after living-donor liver transplantation (LDLT). Material and Methods During January 2007 and December 2013, 51 patients who underwent PPB of the liver under the suspicion of post-LDLT graft rejection were retrospectively analyzed. A total of 73 biopsies were performed. Biopsy was performed with a 17-gauge core needle and 18-gauge cutting needle. The needle tract was embolized using gelatin sponge (n = 44) or N-butyl cyanoacrylate (NBCA) (n = 29). The specimens were reviewed to determine their adequacy for histologic diagnosis. We reviewed all medical records after PPB. Results Specimens were successfully acquired in all procedures (100%). They were adequate for diagnosis in 70 cases (95.9%) and inadequate in three (1.3%). Average of 9.8 complete portal tracts was counted per specimen. One minor complication (1.4%) occurred where the patient had transient fever after the procedure. Conclusion PPB is easy and safe to perform in LDLT recipients and provides high diagnostic yield.

Prognostic significance of microvascular invasion in tumor stage for hepatocellular carcinoma.

BACKGROUND: The presence of microvascular invasion (McVI) in hepatocellular carcinoma (HCC) has been proposed as a cause of recurrence and poor survival, although this has not been officially emphasized in staging systems. Thus, we conducted a retrospective study to investigate the prognostic importance of McVI in tumor staging in patients with HCC who underwent hepatic resection. METHODS: A retrospective analysis was performed of patients who underwent hepatic resection for HCC at our center from 1994 to 2012. Patients with HCC were classified into four groups based on the presence of McVI and extent of gross vascular invasion (VI). RESULTS: The 5-year overall and recurrence-free survival rates of 676 patients were 63.3 and 42.6%, respectively. There was no difference in tumor recurrence or survival rate between patients with HCC and McVI without gross VI and those with gross VI confined to segmental/sectional branches. Multivariate analysis revealed that the extent of VI based on the presence of McVI and gross VI was independently associated with tumor recurrence and overall survival. CONCLUSIONS: McVI was revealed to be an important risk factor similar to gross VI confined to a segmental/sectional branch in patients with HCC who underwent hepatic resection. This finding should be considered when estimating the stage for prognosis.

Mitochondrial Respiratory Dysfunction Induces Claudin-1 Expression via Reactive Oxygen Species-mediated Heat Shock Factor 1 Activation, Leading to Hepatoma Cell Invasiveness.

Although mitochondrial dysfunction has been implicated in tumor metastasis, it is unclear how it regulates tumor cell aggressiveness. We have reported previously that human hepatoma cells harboring mitochondrial defects have high tumor cell invasion activity via increased claudin-1 (Cln-1) expression. In this study, we demonstrated that mitochondrial respiratory defects induced Cln-1 transcription via reactive oxygen species (ROS)-mediated heat shock factor 1 (HSF1) activation, which contributed to hepatoma invasiveness. We first confirmed the inverse relationship between mitochondrial defects and Cln-1 induction in SNU hepatoma cells and hepatocellular carcinoma tissues. We then examined five different respiratory complex inhibitors, and complex I inhibition by rotenone most effectively induced Cln-1 at the transcriptional level. Rotenone increased both mitochondrial and cytosolic ROS. In addition, rotenone-induced Cln-1 expression was attenuated by N-acetylcysteine, an antioxidant, and exogenous H2O2 treatment was enough to increase Cln-1 transcription, implying the involvement of ROS. Next we found that ROS-mediated HSF1 activation via hyperphosphorylation was the key event for Cln-1 transcription. Moreover, the Cln-1 promoter region (from -529 to +53) possesses several HSF1 binding elements, and this region showed increased promoter activity and HSF1 binding affinity in response to rotenone treatment. Finally, we demonstrated that the invasion activity of SNU449 cells, which harbor mitochondrial defects, was blocked by siRNA-mediated HSF1 knockdown. Taken together, these results indicate that mitochondrial respiratory defects enhance Cln-1-mediated hepatoma cell invasiveness via mitochondrial ROS-mediated HSF1 activation, presenting a potential role for HSF1 as a novel mitochondrial retrograde signal-responsive transcription factor to control hepatoma cell invasiveness.

Quantitative Assessment of the Portal Pressure for the Liver Surgery Using Serological Tests.

OBJECTIVE: To establish a reliable equation to predict hepatic venous pressure gradient (HVPG) using serological tests for surgical patients with hepatocellular carcinoma (HCC). BACKGROUND: Accurate assessment of portal pressure for surgical patients with HCC is important for safe hepatic resection (HR). The HVPG is regarded as the most reliable method to detect portal hypertension. However, HVPG is not utilized in many medical centers due to invasiveness of procedure. METHODS: Between 2006 and 2008, 171 patients (Correlation cohort), who underwent liver surgery in a tertiary hospital, were enrolled. Preoperative measurements of the HVPG and serological tests were performed simultaneously. Correlation between the HVPG and serological tests were analyzed to establish an equation for calculated HVPG (cHVPG). Between 2008 and 2013, 510 surgical patients (Application cohort) were evaluated, and HR recommended when cHVPG < 10 mm Hg. The outcomes of HR were analyzed to evaluate reliability of the cHVPG for HR. RESULTS: In the correlation cohort, the equation for cHVPG was established using multivariate linear regression analysis; cHVPG (mm Hg) = 0.209 × [ICG-R15 (%)] - 1.646 × [albumin (g/dL)] - 0.01×[platelet count (10)] + 1.669 × [PT-INR] + 8.911. In the application cohort, 425 patients with cHVPG < 10 mm Hg underwent HR. Among them, 357 had favorable value of ICG-R15 < 20% (group A), and 68 had unfavorable value of ICG-R15 ≥ 20% (group B). There was no significant difference in patient demographics, tumor characteristics, operative outcome, and survival rates between group A and B. CONCLUSIONS: The equation for cHVPG of this study was established on statistical reliability. The cHVPG could be useful to predict portal pressure quantitatively for surgical patients with HCC using serological tests.

Identification of a mitochondrial defect gene signature reveals NUPR1 as a key regulator of liver cancer progression.

UNLABELLED: Many cancer cells require more glycolytic adenosine triphosphate production due to a mitochondrial respiratory defect. However, the roles of mitochondrial defects in cancer development and progression remain unclear. To address the role of transcriptomic regulation by mitochondrial defects in liver cancer cells, we performed gene expression profiling for three different cell models of mitochondrial defects: cells with chemical respiratory inhibition (rotenone, thenoyltrifluoroacetone, antimycin A, and oligomycin), cells with mitochondrial DNA depletion (Rho0), and liver cancer cells harboring mitochondrial defects (SNU354 and SNU423). By comparing gene expression in the three models, we identified 10 common mitochondrial defect-related genes that may be responsible for retrograde signaling from cancer cell mitochondria to the intracellular transcriptome. The concomitant expression of the 10 common mitochondrial defect genes is significantly associated with poor prognostic outcomes in liver cancers, suggesting their functional and clinical relevance. Among the common mitochondrial defect genes, we found that nuclear protein 1 (NUPR1) is one of the key transcription regulators. Knockdown of NUPR1 suppressed liver cancer cell invasion, which was mediated in a Ca(2+) signaling-dependent manner. In addition, by performing an NUPR1-centric network analysis and promoter binding assay, granulin was identified as a key downstream effector of NUPR1. We also report association of the NUPR1-granulin pathway with mitochondrial defect-derived glycolytic activation in human liver cancer. CONCLUSION: Mitochondrial respiratory defects and subsequent retrograde signaling, particularly the NUPR1-granulin pathway, play pivotal roles in liver cancer progression.

Low serum interleukin-6 levels as a predictive marker of recurrence in patients with hepatitis B virus related hepatocellular carcinoma who underwent curative treatment.

BACKGROUND: We aimed to investigate the use of novel serum biomarkers for predicting the recurrence and survival of patients with hepatitis B virus (HBV)-related early hepatocellular carcinoma (HCC) after hepatic resection or radiofrequency ablation (RFA). METHODS: One hundred and five patients with HBV-related HCC, who fulfilled the Milan criteria without vascular invasion and underwent hepatic resection or RFA, were followed-up for a median duration of 52months. Pretreatment serum concentrations of 16 cytokines including interleukin-6 (IL-6) were measured by using a Luminex 200 system. The measured serum cytokines and several clinical factors were analyzed retrospectively. RESULTS: Univariate analysis showed that patients with lower pretreatment serum levels of IL-10, IL-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α had significantly shorter disease-free survival (DFS) than those with higher levels. Multivariate analysis revealed that a low serum IL-6 level (⩽33.00pg/mL; hazard ratio [HR]=5.39; 95% confidence interval [CI]=1.27-22.93; P=0.022), low platelet count (<100×10(9)/L; HR=2.23; 95% CI=1.28-3.89; P=0.005), and low serum albumin level (⩽3.5g/L; HR=2.26; 95% CI=1.28-3.97; P=0.005) had a negative prognostic impact on DFS. In the analysis for overall survival, a low serum platelet level (<100×10(9)/L; HR=2.80; 95% CI=1.31-5.99; P=0.008) and multiple tumor (⩾2; HR=4.05; 95% CI=1.56-10.48; P=0.004) showed a negative prognostic impact on the overall survival. CONCLUSION: A low serum IL-6 level is, in addition to low platelet count and low serum albumin level, an independent prognostic factor for DFS in patients with HBV-related early HCC who underwent hepatic resection or RFA with curative intention.

AROS Is a Significant Biomarker for Tumor Aggressiveness in Non-cirrhotic Hepatocellular Carcinoma.

Despite a low risk of liver failure and preserved liver function, non-cirrhotic hepatocellular carcinoma (HCC) has a poor prognosis. In the current study, we evaluated an active regulator of SIRT1 (AROS) as a prognostic biomarker in non-cirrhotic HCC. mRNA levels of AROS were measured in tumor and non-tumor tissues obtained from 283 non-cirrhotic HCC patients. AROS expression was exclusively up-regulated in recurrent tissues from the non-cirrhotic HCC patients (P = 0.015) and also in tumor tissues irrespective of tumor stage (P < 0.001) or BCLC stage (P < 0.001). High mRNA levels of AROS were statistically significantly associated with tumor stage (P < 0.001), BCLC stage (P = 0.007), alpha fetoprotein (AFP) level (P = 0.013), microvascular invasion (P = 0.001), tumor size (P = 0.036), and portal vein invasion (P = 0.005). Kaplan-Meir curve analysis demonstrated that HCC patients with higher AROS levels had shorter disease-free survival (DFS) in both the short-term (P < 0.001) and long-term (P = 0.005) compared to those with low AROS. Cox regression analysis demonstrated that AROS is a significant predictor for DFS along with large tumor size, tumor multiplicity, vascular invasion, and poor tumor differentiation, which are the known prognostic factors. In conclusion, AROS is a significant biomarker for tumor aggressiveness in non-cirrhotic hepatocellular carcinoma.

Comparative interactomes of SIRT6 and SIRT7: Implication of functional links to aging.

Sirtuins are NAD(+) -dependent deacetylases that regulate a range of cellular processes. Although diverse functions of sirtuins have been proposed, those functions of SIRT6 and SIRT7 that are mediated by their interacting proteins remain elusive. In the present study, we identified SIRT6- and SIRT7-interacting proteins, and compared their interactomes to investigate functional links. Our interactomes revealed 136 interacting proteins for SIRT6 and 233 for SIRT7 while confirming seven and 111 proteins identified previously for SIRT6 and SIRT7, respectively. Comparison of SIRT6 and SIRT7 interactomes under the same experimental conditions disclosed 111 shared proteins, implying related functional links. The interaction networks of interactomes indicated biological processes associated with DNA repair, chromatin assembly, and aging. Interactions of two highly acetylated proteins, nucleophosmin (NPM1) and nucleolin, with SIRT6 and SIRT7 were confirmed by co-immunoprecipitation. NPM1 was found to be deacetylated by both SIRT6 and SIRT7. In senescent cells, the acetylation level of NPM1 was increased in conjunction with decreased levels of SIRT6 and SIRT7, suggesting that the acetylation of NPM1 could be regulated by SIRT6 and SIRT7 in the aging process. Our comparative interactomic study of SIRT6 and SIRT7 implies important functional links to aging by their associations with interacting proteins. All MS data have been deposited in the ProteomeXchange with identifiers PXD000159 and PXD000850 (http://proteomecentral.proteomexchange.org/dataset/PXD000159, http://proteomecentral.proteomexchange.org/dataset/PXD000850).

Time of hepatocellular carcinoma recurrence after liver resection and alpha-fetoprotein are important prognostic factors for salvage liver transplantation.

Salvage liver transplantation (LT) is considered a feasible option for the treatment of recurrent hepatocellular carcinoma (HCC). We performed this multicenter study to assess the risk factors associated with the recurrence of HCC and patient survival after salvage LT. Between January 2000 and December 2011, 101 patients who had previously undergone liver resection (LR) for HCC underwent LT at 3 transplant centers in Korea. Sixty-nine patients' data were retrospectively reviewed for the analysis. The recurrence of HCC was diagnosed at a median of 10.6 months after the initial LR, and patients underwent salvage LT. Recurrences were within the Milan criteria in 48 cases and were outside the Milan criteria in 21 cases. After salvage LT, 31 patients had HCC recurrence during a median follow-up period of 24.5 months. There were 24 deaths, and 20 were due to HCC recurrence. The 5-year overall survival rate was approximately 54.6%, and the 5-year recurrence-free survival rate was 49.3%. HCC recurrence within the 8 months after LR [hazard ratio (HR) = 3.124, P = 0.009], an alpha-fetoprotein level higher than 200 ng/mL (HR = 2.609, P = 0.02), and HCC outside the Milan criteria at salvage LT (HR = 2.219, P = 0.03) were independent risk factors for poor recurrence-free survival after salvage LT. In conclusion, the timing and extent of HCC recurrence after primary LR both play significant roles in the outcome of salvage LT.

Safety and efficacy of early corticosteroid withdrawal in liver transplant recipients: A randomized controlled trial.

Backgrounds/Aims: Prolonged use of steroids after liver transplantation (LT) significantly increases the risk of diabetes or cardiovascular disease, which can adversely affect patient outcomes. Our study evaluated the effectiveness and safety of early steroid withdrawal within the first year following LT. Methods: This study was conducted as an open-label, multicenter, randomized controlled trial. Liver transplant recipients were randomly assigned to one of the following two groups: Group 1, in which steroids were withdrawn two weeks posttransplantation, and Group 2, in which steroids were withdrawn three months posttransplantation. This study included participants aged 20 to 70 years who were scheduled to undergo a single-organ liver transplant from a living or deceased donor at one of the four participating centers. Results: Between November 2012 and August 2020, 115 patients were selected and randomized into two groups, with 60 in Group 1 and 55 in Group 2. The incidence of new-onset diabetes after transplantation (NODAT) was notably higher in Group 1 (32.4%) than in Group 2 (10.0%) in the per-protocol set. Although biopsy-proven acute rejection, graft failure, and mortality did not occur, the median tacrolimus trough level/dose/weight in Group 1 exceeded that in Group 2. No significant differences in safety parameters, such as infection and recurrence of hepatocellular carcinoma, were observed between the two groups. Conclusions: The present study did not find a significant reduction in the incidence of NODAT in the early steroid withdrawal group. Our study suggests that steroid withdrawal three months posttransplantation is a standard and safe immunosuppressive strategy for LT patients.