Robotic and laparoscopic right lobe living donation compared to the open approach: A multicenter study on 1194 donor hepatectomies.

Due to the success of minimally invasive liver surgery, laparoscopic and robotic minimally invasive donor hepatectomies (MIDH) are increasingly performed worldwide. We conducted a retrospective, multicentre, propensity score-matched analysis on right lobe MIDH by comparing the robotic, laparoscopic, and open approaches to assess the feasibility, safety, and early outcomes of MIDHs. From January 2016 until December 2020, 1194 donors underwent a right donor hepatectomy performed with a robotic (n = 92), laparoscopic (n = 306), and open approach (n = 796) at 6 high-volume centers. Donor and recipients were matched for different variables using propensity score matching (1:1:2). Donor outcomes were recorded, and postoperative pain was measured through a visual analog scale. Recipients' outcomes were also analyzed. Ninety-two donors undergoing robotic surgery were matched and compared to 92 and 184 donors undergoing laparoscopic and open surgery, respectively. Conversions to open surgery occurred during 1 (1.1%) robotic and 2 (2.2%) laparoscopic procedures. Robotic procedures had a longer operative time (493 ± 96 min) compared to laparoscopic and open procedures (347 ± 120 and 358 ± 95 min; p < 0.001) but were associated with reduced donor blood losses ( p < 0.001). No differences were observed in overall and major complications (≥ IIIa). Robotic hepatectomy donors had significantly less pain compared to the 2 other groups ( p < 0.001). Fifty recipients of robotic-procured grafts were matched to 50 and 100 recipients of laparoscopic and open surgery procured grafts, respectively. No differences were observed in terms of postoperative complications, and recipients' survival was similar ( p =0.455). In very few high-volume centers, robotic right lobe procurement has shown to be a safe procedure. Despite an increased operative and the first warm ischemia times, this approach is associated with reduced intraoperative blood losses and pain compared to the laparoscopic and open approaches. Further data are needed to confirm it as a valuable option for the laparoscopic approach in MIDH.

The learning curve for robotic living donor right hepatectomy: Analysis of outcomes in two specialized centers.

Robotic surgery is an emerging minimally invasive option for living donor hepatectomy. Currently, there are no studies on the learning curve of robotic donor hepatectomy. Thus, we evaluated the learning curve for robotic donor right hepatectomy (RH). We retrospectively reviewed prospectively collected data from consecutive living donors who underwent robotic hepatectomy at two specialized centers between 2016 and 2022. We estimated the number of cases required to achieve stable operating times for robotic donor RH using cumulative sum (CUSUM) analysis. The complication rates were similar between the two centers (22.8% vs. 26.7%; p=0.74). Most complications were graded as minor (70.4%). Analysis of the total operative time demonstrated that the learning curves reached a peak at the 17th case in Center 1 and the 9th case in Center 2. The average operation times for cases 1-17 versus 18-99 in Center 1 were 603 versus 438 minutes (p<0.001), and cases 1-9 versus 10-15 in Center 2 were 532 versus 418 minutes (p=0.002). Complication rates were lower after the learning curves were achieved, although this did not reach statistical significance. A comparison of outcomes between centers suggests that a standardized approach to this complex operation can be successfully transferred.

Intraindividual comparison of prognostic imaging features of HCCs between MRIs with extracellular and hepatobiliary contrast agents.

BACKGROUND & AIMS: Accumulating evidence suggests that certain imaging features of hepatocellular carcinoma (HCC) may have prognostic implications. This study aimed to intraindividually compare MRIs with extracellular contrast agent (ECA-MRI) and hepatobiliary agent (HBA-MRI) for prognostic imaging features of HCC and to compare the prediction of microvascular invasion (MVI) and early recurrence between the two MRIs. METHODS: The present study included 102 prospectively enrolled at-risk patients (median age, 61.0 years; 83 men) with surgically resected single HCC with both preoperative ECA-MRI and HBA-MRI between July 2019 and June 2023. The McNemar test was used to compare each prognostic imaging feature between the two MRIs. Significant imaging features associated with MVI were identified by multivariable logistic regression analysis, and early recurrence rates (<2 years) were compared between the two MRIs. RESULTS: The frequencies of prognostic imaging features were not significantly different between the two MRIs (p = .07 to >.99). Non-smooth tumour margin (ECA-MRI, odds ratio [OR] = 5.30; HBA-MRI, OR = 7.07) and peritumoral arterial phase hyperenhancement (ECA-MRI, OR = 4.26; HBA-MRI, OR = 4.43) were independent factors significantly associated with MVI on both MRIs. Two-trait predictor of venous invasion (presence of internal arteries and absence of hypoattenuating halo) on ECA-MRI (OR = 11.24) and peritumoral HBP hypointensity on HBA-MRI (OR = 20.42) were other predictors of MVI. Early recurrence rates of any two or more significant imaging features (49.8% on ECA-MRI vs 51.3% on HBA-MRI, p = .75) were not significantly different between the two MRIs. CONCLUSION: Prognostic imaging features of HCC may be comparable between ECA-MRI and HBA-MRI.

An explainable machine learning model to predict early and late acute kidney injury after major hepatectomy.

BACKGROUND: Risk assessment models for acute kidney injury (AKI) after major hepatectomy that differentiate between early and late AKI are lacking. This retrospective study aimed to create a model predicting AKI through machine learning and identify features that contribute to the development of early and late AKI. METHODS: Patients that underwent major hepatectomy were categorized into the No-AKI, Early-AKI (within 48 h) or Late-AKI group (between 48 h and 7 days). Modeling was done with 20 perioperative features and the performance of prediction models were measured by the area under the receiver operating characteristic curve (AUROCC). Shapley Additive Explanation (SHAP) values were utilized to explain the outcome of the prediction model. RESULTS: Of the 1383 patients included in this study, 1229, 110 and 44 patients were categorized into the No-AKI, Early-AKI and Late-AKI group, respectively. The CatBoost classifier exhibited the greatest AUROCC of 0.758 (95% CI: 0.671-0.847) and was found to differentiate well between Early and Late-AKI. We identified different perioperative features for predicting each outcome and found 1-year mortality to be greater for Early-AKI. CONCLUSIONS: Our results suggest that risk factors are different for Early and Late-AKI after major hepatectomy, and 1-year mortality is greater for Early-AKI.

Tcf7l2 in hepatocytes regulates de novo lipogenesis in diet-induced non-alcoholic fatty liver disease in mice.

AIMS/HYPOTHESIS: Non-alcoholic fatty liver disease (NAFLD) associated with type 2 diabetes may more easily progress towards severe forms of non-alcoholic steatohepatitis (NASH) and cirrhosis. Although the Wnt effector transcription factor 7-like 2 (TCF7L2) is closely associated with type 2 diabetes risk, the role of TCF7L2 in NAFLD development remains unclear. Here, we investigated how changes in TCF7L2 expression in the liver affects hepatic lipid metabolism based on the major risk factors of NAFLD development. METHODS: Tcf7l2 was selectively ablated in the liver of C57BL/6N mice by inducing the albumin (Alb) promoter to recombine Tcf7l2 alleles floxed at exon 5 (liver-specific Tcf7l2-knockout [KO] mice: Alb-Cre;Tcf7l2f/f). Alb-Cre;Tcf7l2f/f and their wild-type (Tcf7l2f/f) littermates were fed a high-fat diet (HFD) or a high-carbohydrate diet (HCD) for 22 weeks to reproduce NAFLD/NASH. Mice were refed a standard chow diet or an HCD to stimulate de novo lipogenesis (DNL) or fed an HFD to provide exogenous fatty acids. We analysed glucose and insulin sensitivity, metabolic respiration, mRNA expression profiles, hepatic triglyceride (TG), hepatic DNL, selected hepatic metabolites, selected plasma metabolites and liver histology. RESULTS: Alb-Cre;Tcf7l2f/f essentially exhibited increased lipogenic genes, but there were no changes in hepatic lipid content in mice fed a normal chow diet. However, following 22 weeks of diet-induced NAFLD/NASH conditions, liver steatosis was exacerbated owing to preferential metabolism of carbohydrate over fat. Indeed, hepatic Tcf7l2 deficiency enhanced liver lipid content in a manner that was dependent on the duration and amount of exposure to carbohydrates, owing to cell-autonomous increases in hepatic DNL. Mechanistically, TCF7L2 regulated the transcriptional activity of Mlxipl (also known as ChREBP) by modulating O-GlcNAcylation and protein content of carbohydrate response element binding protein (ChREBP), and targeted Srebf1 (also called SREBP1) via miRNA (miR)-33-5p in hepatocytes. Eventually, restoring TCF7L2 expression at the physiological level in the liver of Alb-Cre;Tcf7l2f/f mice alleviated liver steatosis without altering body composition under both acute and chronic HCD conditions. CONCLUSIONS/INTERPRETATION: In mice, loss of hepatic Tcf7l2 contributes to liver steatosis by inducing preferential metabolism of carbohydrates via DNL activation. Therefore, TCF7L2 could be a promising regulator of the NAFLD associated with high-carbohydrate diets and diabetes since TCF7L2 deficiency may lead to development of NAFLD by promoting utilisation of excess glucose pools through activating DNL. DATA AVAILABILITY: RNA-sequencing data have been deposited into the NCBI GEO under the accession number GSE162449 ( www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE162449 ).

Left-sided Hepatectomy Leads to Less Postoperative Liver Failure and Comparable Overall Survival to Right-sided Hepatectomy in Type II or IV Perihilar Cholangiocarcinoma.

INTRODUCTION: Right-side hepatectomy (RH) is used in oncological resection for perihilar cholangiocarcinoma (PHC); however, the decision between performing left-side hepatectomy (LH) or RH is still controversial. We compared surgical and oncologic outcomes of LH and RH in PHC type II or IV where either hepatectomy was expected to have a negative margin. METHODS: From 2001 to 2020, 99 patients underwent major liver resection for type II or IV PHC. Patients with unilateral vascular invasion, unilateral tumor growth, and atrophy of unilateral liver were excluded. Preoperative characteristics, perioperative, and long-term outcomes were compared between the remaining RH and LH patients. RESULTS: After excluding 47 cases with side predominance, the RH group (n = 29) and LH group (n = 23) were compared. Clinical characteristics and disease severity did not differ between the groups. Portal vein embolization (RH: 48.3% vs. LH: 0.0%, p < 0.001) and days from diagnosis to operation (RH: 31.0 ± 16.2 vs. LH: 18.8 ± 13.4, p = 0.006) were significantly higher in the RH group. The RH group had statistically higher rate of postoperative hepatic failure (RH: 55.2% vs. LH: 21.7%, p = 0.015) and a higher mortality rate that was not significant (RH: 13.8% vs. LH: 0%, p = 0.120). The R0 resection rate (RH: 72.4% vs. LH: 78.3%, p = 0.629), median disease-free (p = 0.620), and overall (p = 0.487) survival did not differ between groups. R1 resection and lymph node metastasis were significant risk factors for disease-free survival in multivariate analysis. CONCLUSIONS: In type II or type IV PHC where either LH or RH was feasible, LH provided a shorter period of preoperative preparation, lower postoperative hepatic failure rate, similar R0 rate, and comparable long-term outcomes. LH should be considered a reasonable option in type II or IV PHC.

Hepatic arterial infusion in combination with systemic chemotherapy in patients with hepatic metastasis from colorectal cancer: a randomized phase II study - (NCT05103020) - study protocol.

BACKGROUND: Although 80% of patients with metastatic colorectal cancer (CRC) experience liver metastases, only 10-25% undergo resection at the time of diagnosis. Even in initially unresectable conditions, if appropriate treatment is provided, such as surgical conversion through a combination of hepatic arterial infusion (HAI) chemotherapy and systemic chemotherapy (sys-CT), better overall survival can be expected. Therefore, this study aims to evaluate the efficacy of HAI oxaliplatin in combination with sys-CT plus targeted therapy in patients with unresectable CRC with liver-only metastasis. METHODS: This is a single-center, randomized, open-label phase II trial (NCT05103020). Patients with untreated CRC, who have liver-only metastases and for whom liver resection is potentially possible but deemed infeasible at the time of initial diagnosis by a multidisciplinary team, will be eligible. Patients will be randomly assigned in a 1:1 ratio to either the combined HAI oxaliplatin and modified systemic 5-fluorouracil, folinic acid, and irinotecan (FOLFIRI) plus targeted therapy group or the systemic FOLFIRI plus targeted therapy group. Both regimens will be repeated every 2 weeks for a total of 12 cycles. The primary objective of this study is to compare the rate of conversion to liver resection. The surgical conversion rate is expected to increase by 25% with HAI oxaliplatin in combination with sys-CT plus targeted therapy (40% in the experimental arm versus 15% in the control arm) (power, 80%; two-sided alpha-risk, 5%). The secondary objectives include overall survival, progression-free survival, and objective response rate. DISCUSSION: This is the first randomized controlled trial to investigate the efficacy of HAI oxaliplatin in combination with sys-CT plus targeted therapy as first-line treatment from the initial diagnosis in patients with unresectable CRC with liver-only metastasis, aiming to significantly increase the surgical conversion rate. TRIAL REGISTRATION: ClinicalTrials.gov, (NCT05103020). Trial registration date: November 2, 2021.

Prognostic impact of R1 resection margin in synchronous and simultaneous colorectal liver metastasis resection: a retrospective cohort study.

BACKGROUND: A margin ≥ 1 mm is considered a standard resection margin for colorectal liver metastasis (CRLM). However, microscopic incomplete resection (R1) is not rare since aggressive surgical resection has been attempted in multiple and bilobar CRLM. This study aimed to investigate the prognostic impact of resection margins and perioperative chemotherapy in patients with CRLM. METHODS: A total of 368 of 371 patients who underwent simultaneous colorectal and liver resection for synchronous CRLM between 2006 and June 2017, excluding three R2 resections, were included in this study. R1 resection was defined as either abutting tumor on the resection line or involved margin in the pathological report. The patients were divided into R0 (n = 304) and R1 (n = 64) groups. The clinicopathological characteristics, overall survival, and intrahepatic recurrence-free survival were compared between the two groups using propensity score matching. RESULTS: The R1 group had more patients with ≥ 4 liver lesions (27.3 vs. 50.0%, P < 0.001), higher mean tumor burden score (4.4 vs. 5.8%, P = 0.003), and more bilobar disease (38.8 vs. 67.2%, P < 0.001) than the R0 group. Both R0 and R1 groups showed similar long-term outcomes in the total cohort (OS, P = 0.149; RFS, P = 0.414) and after matching (OS, P = 0.097, RFS: P = 0.924). However, the marginal recurrence rate was higher in the R1 group than in the R0 group (26.6 vs. 16.1%, P = 0.048). Furthermore, the resection margin did not have a significant impact on OS and RFS, regardless of preoperative chemotherapy. Poorly differentiated, N-positive stage colorectal cancer, liver lesion number ≥ 4, and size ≥ 5 cm were poor prognostic factors, and adjuvant chemotherapy had a positive impact on survival. CONCLUSIONS: The R1 group was associated with aggressive tumor characteristics; however, no effect on the OS and intrahepatic RFS with or without preoperative chemotherapy was observed in this study. Tumor biological characteristics, rather than resection margin status, determine long-term prognosis. Therefore, aggressive surgical resection should be considered in patients with CRLM expected to undergo R1 resection in this multidisciplinary approach era.

Outcomes of Robotic Living Donor Right Hepatectomy From 52 Consecutive Cases: Comparison With Open and Laparoscopy-assisted Donor Hepatectomy.

OBJECTIVE: To investigate the feasibility and safety of RLDRH. SUMMARY OF BACKGROUND DATA: Data for minimally invasive living-donor right hepatectomy, especially RLDRH, from a relatively large donor cohort that have not been reported yet. METHODS: From March 2016 to March 2019, 52 liver donors underwent RLDRH. The clinical and perioperative outcomes of RLDRH were compared with those of CODRH (n = 62) and LADRH (n = 118). Donor satisfaction with cosmetic results was compared between RLDRH and LADRH using a body image questionnaire. RESULTS: Although RLDRH was associated with longer operative time (minutes) (RLDRH, 493.6; CODRH, 404.4; LADRH, 355.9; P < 0.001), mean estimated blood loss (mL) was significantly lower (RLDRH, 109.8; CODRH, 287.1; LADRH, 265.5; P = 0.001). Postoperative complication rates were similar among the 3 groups (RLDRH, 23.1%; CODRH, 35.5%; LADRH, 28.0%; P = 0.420). Regarding donor satisfaction, body image and cosmetic appearance scores were significantly higher in RLDRH than in LADRH. After propensity score matching, RLDRH showed less estimated blood loss compared to those of CODRH (RLDRH, 114.7 mL; CODRH, 318.4 mL; P < 0.001), but complication rates were similar among the three groups (P = 0.748). CONCLUSIONS: RLDRH resulted in less blood loss compared with that of CODRH and similar postoperative complication rates to CODRH and LADRH. RLDRH provided better body image and cosmetic results compared with those of LADRH. RLDRH is feasible and safe when performed by surgeons experienced with both robotic and open hepatectomy.

Perioperative management of living donor liver transplantation: Part 2 - Donors.

Living donor liver transplantation was first developed to mitigate the limited access to deceased donor organs in Asia in the 1990s. This alternative liver transplantation method has become a widely practiced and established transplantation option for adult patients suffering with end-stage liver disease, and it has successfully helped address the shortage of deceased donors. The Society for the Advancement of Transplant Anesthesia and the Korean Society of Transplantation Anesthesiologists jointly reviewed published studies on the perioperative management of adult live liver donors undergoing donor hemi-hepatectomy. The goal of the review is to offer transplant anesthesiologists and critical care physicians a comprehensive overview of the perioperative management of adult live donors. We featured the current status, donor selection process, outcomes and complications, surgical procedure, anesthetic management, Enhanced Recovery After Surgery protocols, avoidance of blood transfusion, and considerations for emergency donation. Recent surgical advances, including laparoscopic donor hemi-hepatectomy and robotic laparoscopic donor surgery, are also addressed.

Laparoscopic Minor Liver Resections for Hepatocellular Carcinoma in the Posterosuperior Segments Using the Rubber Band Technique.

BACKGROUND: Although laparoscopic minor liver resections (LLR) of posterosuperior (PS) segments are technically challenging, several expert centers are increasingly performing this procedure. In the present study, we introduced novel techniques, including the rubber band traction method and positional changes, and compared surgical outcomes of LLR for hepatocellular carcinoma (HCC) located in PS segments with open minor liver resection (OLR). METHODS: From January 2008 to August 2019, 113 patients underwent laparoscopic (n = 55) or open (n = 58) minor liver resections for single small HCCs (<5 cm) located in PS segments. Propensity score matching in a 1:1 ratio was conducted to minimize preoperative selection bias, and surgical outcomes were compared between the two groups. RESULTS: There was no intraoperative mortality or reoperation in either group. One conversion to open surgery was necessary due to severe post-operative adhesions. The matched LLR group compared to OLR had significantly shorter operative time (215.16 vs. 251.41 min, P = 0.025), lesser blood loss (218.11 vs. 358.92 mL, P = 0.046), lower complication rate (8.1% vs. 29.7%, P = 0.018), and shorter hospital stay (7.03 vs. 11.78 days, P = 0.001). Intraoperative transfusion, R0 resection, resection margin, 5-year disease-free survival and 5-year overall survival were comparable. CONCLUSION: Our standardized LLR provided improved short-term outcomes and similar long-term outcomes, when compared with OLR. With advanced techniques and accumulated surgical experience, LLR can be the first option for HCC in PS segments at expert centers.

Gadoxetic acid-enhanced MRI of macrotrabecular-massive hepatocellular carcinoma and its prognostic implications.

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.

Subclassification of Microscopic Vascular Invasion in Hepatocellular Carcinoma.

OBJECTIVE: To investigate whether subclassification of microscopic vascular invasion (MiVI) affects the long-term outcome after curative surgical resection or liver transplantation (LT) in patients with hepatocellular carcinoma (HCC). SUMMARY OF BACKGROUND DATA: The most important factor for TNM staging in HCC is MiVI, which includes all vascular invasions detected on microscopic examination. However, there is a broad spectrum of current definitions for MiVI. METHODS: In total, 412 consecutive patients with HCC who underwent curative surgical resection without any preoperative treatment or gross vascular invasion were histologically evaluated for MiVI. Patients with MiVI were subclassified into 2 groups: microvessel invasion (MI; n = 164) only and microscopic portal vein invasion (MPVI; n = 36). Clinicopathologic features were compared between 2 groups (MI vs MPVI), whereas disease-free survival (DFS) and overall survival (OS) after resection were analyzed among 3 groups (no vascular invasion [NVI] vs MI vs MPVI). These subclassifications were validated in a cohort of 197 patients with HCC who underwent LT. RESULTS: The MPVI group showed more aggressive tumor characteristics, such as higher tumor marker levels (alpha-fetoprotein, P = 0.006; protein induced by vitamin K absence-II, P = 0.001) and poorer differentiation (P = 0.011), than the MI group. In multivariate analysis, both MI and MPVI were independent prognostic factors for DFS (P = 0.001 and <0.001, respectively) and OS (P = 0.005 and <0.001, respectively). In the validation cohort, 5-year DFS was 89%, 67.9%, and 0% in the NVI, MI, and MPVI groups, respectively (P < 0.001), whereas 5-year OS was 79.1%, 55.0%, and 15.4%, respectively (P < 0.001). CONCLUSIONS: Based on subclassification of MiVI in HCC, MPVI was associated with more aggressive clinicopathologic characteristics and poorer survival than MI only. Therefore, the original MiVI classification should be divided into MI and MPVI.

Axl Deficiency Promotes the Neuroinvasion of Japanese Encephalitis Virus by Enhancing IL-1α Production from Pyroptotic Macrophages.

Japanese encephalitis virus (JEV) is a flavivirus that causes Japanese encephalitis (JE), which has an unclear pathogenesis. Despite vaccination, thousands of deaths attributed to JE are reported annually. In this study, we report that mice deficient for Axl, a receptor tyrosine kinase that plays multiple roles in flaviviral infection, displayed greater mortality upon JEV infection. The effect of Axl deficiency on JEV infection was mediated by markedly elevated serum interleukin-1α (IL-1α) levels, which devastated the blood-brain-barrier and promoted viral neuroinvasion within 24 h postinfection. Using an in situ infection model, we showed that dead macrophages were the primary source of observed increased serum IL-1α levels. Axl deficiency enhanced cell death and caused pyroptosis in 80% of JEV-infected macrophages by disrupting phosphatidylinositol 3-kinase (PI3K)-Akt signaling. Intriguingly, the primary effector released by pyroptotic macrophages in our model was IL-1α rather than IL-1ß. Finally, we assessed the effect of an IL-1α antagonist and demonstrated that it effectively prevented the incidence of JE. Our results indicate that Axl plays a protective role in JEV infection, identify IL-1α released by pyroptotic macrophages as a crucial factor promoting JEV neuroinvasion, and suggest that an IL-1α antagonist may be a candidate for JE therapy.IMPORTANCE Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes Japanese encephalitis (JE), the most commonly diagnosed viral encephalitis worldwide. The fatality rate of JE is 20%, and nearly half of the surviving patients develop neuropsychiatric sequelae. Axl is a receptor tyrosine kinase that plays multiple roles in flaviviral infections. Currently, the involvement of Axl in JEV infection remains enigmatic. In this study, we demonstrate that Axl impedes the pathogenesis of severe JE in mice by maintaining blood-brain-barrier (BBB) integrity and restricting viral neuroinvasion. Furthermore, serum IL-1α is a key mediator of this process and is primarily released by JEV-infected pyroptotic macrophages to elicit BBB breakdown, while an IL-1α antagonist can effectively reduce the incidence of severe JE. Our work uncovers the protective role of Axl in antagonizing severe JE and shows that the use of an IL-1α antagonist may be a promising tactic to prevent severe JE.

Major Laparoscopic Versus Open Resection for Hepatocellular Carcinoma: A Propensity Score-Matched Analysis Based on Surgeons' Learning Curve.

BACKGROUND: Surgical complications for surgeons still in the learning phase of major laparoscopic liver resection (LLR) have been frequently observed. We aimed to compare perioperative and long-term outcomes of laparoscopic and open surgery based on the surgeons' learning curve for LLR after propensity score-matched (PSM) analysis. METHODS: This was a retrospective study of all patients with a histologic diagnosis of hepatocellular carcinoma who underwent major hepatectomy between January 2013 and December 2018. A PSM analysis was used to compare the groups of patients who underwent LLR and open major liver resection (OLR) before and after the learning curve was maximized. RESULTS: Among 405 patients, 106 underwent LLR and 299 underwent OLR. The learning curve was maximized after 42 cases. Compared with OLR, LLR had more liver-related injury and grade III or higher complications during the learning phase. The LLR group had less blood loss, fewer transfusion requirements, and fewer liver-related complications during the 'experienced' phase. Hospital stay was significantly shorter during and after maximization of the learning curve in LLR compared with OLR. Operative time was comparable in the two phases. Overall, LLR was associated with less blood loss, fewer complications, and shorter hospital stay compared with open surgery. There was no significant difference in long-term survival outcomes between the two groups. CONCLUSIONS: LLR had a higher incidence of liver-related complications during the surgeon's learning phase compared with OLR. This association was significantly diminished with surgeon experience. Overall perioperative outcomes such as estimated blood loss, surgical complications, and hospital stay remained better for LLR compared with OLR.

Clinical and survival outcomes after hepatectomy in patients with non-alcoholic fatty liver and hepatitis B-related hepatocellular carcinoma.

BACKGROUND: The prevalence of non-alcoholic fatty liver disease-related hepatocellular carcinoma (NAFLD-HCC) has increased parallelly with that of metabolic syndrome. This study aimed to compare the clinical and survival outcomes of NAFLD-HCC and HBV-related HCC(HBV-HCC). METHODS: The medical records of patients who underwent hepatectomy for HCC at Severance Hospital between 2005 and 2015 were retrospectively reviewed. Occult HBV infection was identified by nested PCR. Propensity score matching (PSM) was conducted to minimize lead-time bias caused by the lack of surveillance in NAFLD patients. Surgical and oncologic outcomes were compared between the two groups. RESULTS: There were 32 patients (7%) with NAFLD-HCC, 200 (46%) with HBV-HCC, and 194 (44%) with HBV/NAFLD-HCC (HBV and NAFLD). Before PSM, cirrhosis was more frequently detected in HBV-HCC patients (55% vs 15%, p < 0.001) and the average tumor size was larger in the NAFLD-HCC group than in the HBV-HCC group (4.4 ± 3.3 cm vs 3.4 ± 1.8 cm, p = 0.014). After a median follow-up of 74 months (range 0-157 months), survival analyses before PSM showed better 5-year overall survival (OS) in HBV-HCC patients than in NAFLD-HCC patients (80% vs 63%, p = 0.041). After PSM, 5-year OS rates were similar (60% vs 63%, p = 0.978). There were no differences between the groups in recurrence-free or disease-specific survival before and after PSM. CONCLUSION: Patients with NAFLD-HCC were less likely to have underlying cirrhosis but more likely to have larger tumors at the time of diagnosis than patients with HBV-HCC. The OS of patients with NAFLD-HCC appeared to be worse than that of patients with HBV-HCC. Therefore, active HCC surveillance is recommended in patients with metabolic syndrome for the early detection of HCC.

Identification of ALDH6A1 as a Potential Molecular Signature in Hepatocellular Carcinoma via Quantitative Profiling of the Mitochondrial Proteome.

Various liver diseases, including hepatocellular carcinoma (HCC), have been linked to mitochondrial dysfunction, reduction of reactive oxygen species (ROS), and elevation of nitric oxide (NO). In this study, we subjected the human liver mitochondrial proteome to extensive quantitative proteomic profiling analysis and molecular characterization to identify potential signatures indicative of cancer cell growth and progression. Sequential proteomic analysis identified 2452 mitochondrial proteins, of which 1464 and 2010 were classified as nontumor and tumor (HCC) mitochondrial proteins, respectively, with 1022 overlaps. Further metabolic mapping of the HCC mitochondrial proteins narrowed our biological characterization to four proteins, namely, ALDH4A1, LRPPRC, ATP5C1, and ALDH6A1. The latter protein, a mitochondrial methylmalonate semialdehyde dehydrogenase (ALDH6A1), was most strongly suppressed in HCC tumor regions (∼10-fold decrease) in contrast to LRPPRC (∼6-fold increase) and was predicted to be present in plasma. Accordingly, we selected ALDH6A1 for functional analysis and engineered Hep3B cells to overexpress this protein, called ALDH6A1-O/E cells. Since ALDH6A1 is predicted to be involved in mitochondrial respiration, we assessed changes in the levels of NO and ROS in the overexpressed cell lines. Surprisingly, in ALDH6A1-O/E cells, NO was decreased nearly 50% but ROS was increased at a similar level, while the former was restored by treatment with S-nitroso-N-acetyl-penicillamine. The lactate levels were also decreased relative to control cells. Propidium iodide and Rhodamine-123 staining suggested that the decrease in NO and increase in ROS in ALDH6A1-O/E cells could be caused by depolarization of the mitochondrial membrane potential (ΔΨ). Taken together, our results suggest that hepatic neoplastic transformation appears to suppress the expression of ALDH6A1, which is accompanied by a respective increase and decrease in NO and ROS in cancer cells. Given the close link between ALDH6A1 suppression and abnormal cancer cell growth, this protein may serve as a potential molecular signature or biomarker of hepatocarcinogenesis and treatment responses.

Potential Regulatory Role of Human-Carboxylesterase-1 Glycosylation in Liver Cancer Cell Growth.

We previously reported that human carboxylesterase 1 (CES1), a serine esterase containing a unique N-linked glycosyl group at Asn79 (N79 CES1), is a candidate serological marker of hepatocellular carcinoma (HCC). CES1 is normally present at low-to-undetectable levels in normal human plasma, HCC tumors, and major liver cancer cell lines. To investigate the potential mechanism underlying the suppression of CES1 expression in liver cancer cells, we took advantage of the low detectability of this marker in tumors by overexpressing CES1 in multiple HCC cell lines, including stable Hep3B cells. We found that the population of CES1-overexpressing (OE) cells decreased and that their doubling time was longer compared with mock control liver cancer cells. Using interactive transcriptome, proteome, and subsequent Gene Ontology enrichment analysis of CES1-OE cells, we found substantial decreases in the expression levels of genes involved in cell cycle regulation and proliferation. This antiproliferative function of the N79 glycan of CES1 was further supported by quantitative real-time polymerase chain reaction, flow cytometry, and an apoptosis protein array assay. An analysis of the levels of key signaling target proteins via Western blotting suggested that CES1 overexpression exerted an antiproliferative effect via the PKD1/PKCµ signaling pathway. Similar results were also seen in another HCC cell line (PLC/RFP/5) after transient transfection with CES1 but not in similarly treated non-HCC cell lines (e.g., HeLa and Tera-1 cells), suggesting that CES1 likely exerts a liver cell-type-specific suppressive effect. Given that the N-linked glycosyl group at Asn79 (N79 glycan) of CES1 is known to influence CES1 enzyme activity, we hypothesized that the post-translational modification of CES1 at N79 may be linked to its antiproliferative activity. To investigate the regulatory effect of the N79 glycan on cellular growth, we mutated the single N-glycosylation site in CES1 from Asn to Gln (CES1-N79Q) via site-directed mutagenesis. Fluorescence 2-D difference gel electrophoresis protein expression analysis of cell lysates revealed an increase in cell growth and a decrease in doubling time in cells carrying the N79Q mutation. Thus our results suggest that CES1 exerts an antiproliferative effect in liver cancer cells and that the single N-linked glycosylation at Asn79 plays a potential regulatory role. These functions may underlie the undetectability of CES1 in human HCC tumors and liver cancer cell lines. Mass spectrometry data are available via ProteomeXchange under the identifier PXD021573.

A nomogram based on liver stiffness predicts postoperative complications in patients with hepatocellular carcinoma.

BACKGROUND & AIMS: Liver stiffness measurement (LSM), assessed by transient elastography (Fibroscan), has been demonstrated to predict post-hepatectomy liver failure in patients who undergo hepatic resection for hepatocellular carcinoma (HCC). However, other complications are also likely to be related to the underlying grade of liver fibrosis. Herein, we aimed to identify predictors of postoperative complications and to build and develop a novel nomogram able to identify patients at risk of developing severe complications. METHODS: Data from patients who underwent hepatectomy for HCC between 2006 and 2016 at 2 referral centres were retrospectively reviewed. All surgical complications were recorded and scored using the comprehensive complication index (CCI), ranging from 0 (uneventful course) to 100 (death). A CCI ≥26.2 was used as a threshold to define severe complications. RESULTS: During the study period, 471 patients underwent hepatic resection for HCC. Among them, 50 patients (10.6%) had a CCI ≥26.2. Age, model for end-stage liver disease (MELD) score and LSM values, together with serum albumin, were independent predictors of high CCI. The nomogram built on these variables was internally validated and showed good performance (optimism-corrected c-statistic = 0.751). A regression equation to predict the CCI was also established by multiple linear regression analysis: [LSM (kPa) × 0.254] + [age (years) × 0.118] + [MELD score (pt.) × 1.050] - [albumin (g/dl) × 2.395] - 3.639. CONCLUSION: A novel nomogram, combining LSM values, age and liver function tests provided an excellent preoperative prediction of high CCI in patients with resectable HCC. This predictive model could be used as a reference for clinicians and surgeons to help them in clinical decision-making. LAY SUMMARY: Liver stiffness measurement is increasingly being used to assess the degree of liver fibrosis in patients with cirrhosis and/or chronic hepatitis. Using Fibroscan, we developed a novel nomogram to predict severe complications following liver resection for hepatocellular carcinoma, according to the new comprehensive complication index. This tool could be used as a reference for clinicians and surgeons to help them in clinical decision-making.

Functions of human liver CD69+CD103-CD8+ T cells depend on HIF-2α activity in healthy and pathologic livers.

BACKGROUND & AIMS: Human liver CD69+CD8+ T cells are ~95% CD103- and ~5% CD103+. Although CD69+CD103+CD8+ T cells show tissue residency and robustly respond to antigens, CD69+CD103-CD8+ T cells are not yet well understood. METHODS: Liver perfusate and paired peripheral blood were collected from healthy living donors and recipients with cirrhosis during liver transplantation. Liver tissues were obtained from patients with acute hepatitis A. Phenotypic and functional analyses were performed by flow cytometry. Gene expression profiles were determined by microarray and quantitative reverse transcription PCR. PT-2385 was used to inhibit hypoxia-inducible factor (HIF)-2α. RESULTS: Human liver CD69+CD103-CD8+ T cells exhibited HIF-2α upregulation with a phenotype of tissue residency and terminal differentiation. CD103- cells comprised non-hepatotropic virus-specific T cells as well as hepatotropic virus-specific T cells, but CD103+ cells exhibited only hepatotropic virus specificity. Although CD103- cells were weaker effectors on a per cell basis than CD103+ cells, following T cell receptor or interleukin-15 stimulation, they remained the major CD69+CD8+ effector population in the liver, surviving with less cell death. An HIF-2α inhibitor suppressed the effector functions and survival of CD69+CD103-CD8+ T cells. In addition, HIF-2α expression in liver CD69+CD103-CD8+ T cells was significantly increased in patients with acute hepatitis A or cirrhosis. CONCLUSIONS: Liver CD69+CD103-CD8+ T cells are tissue resident and terminally differentiated, and their effector functions depend on HIF-2α. Furthermore, activation of liver CD69+CD103-CD8+ T cells with HIF-2α upregulation is observed during liver pathology. LAY SUMMARY: The immunologic characteristics and the role of CD69+CD103-CD8+ T cells, which are a major population of human liver CD8+ T cells, remain unknown. Our study shows that these T cells have a terminally differentiated tissue-resident phenotype, and their effector functions depend on a transcription factor, HIF-2α. Furthermore, these T cells were activated and expressed higher levels of HIF-2α in liver pathologies, suggesting that they play an important role in immune responses in liver tissues and the pathogenesis of human liver disease.