Effect of sofosbuvir and velpatasvir therapy on clinical outcome in hepatitis C virus patients with decompensated cirrhosis.

AIM: To determine the impact of direct-acting antiviral therapy on the long-term prognosis of decompensated cirrhotic patients. METHODS: A total of 37 patients with hepatitis C virus-induced decompensated cirrhosis treated with sofosbuvir and velpatasvir (SOF/VEL group) were prospectively enrolled. For historical control, 65 hepatitis C virus-positive decompensated cirrhotic patients who did not receive direct-acting antiviral therapy were included (control group). The incidence rates of hepatocellular carcinoma (HCC), decompensated events with hospitalization, and overall survival were compared between both groups. RESULTS: A total of 41 patients experienced decompensated events during 15.0 months in the control group, and six patients during 21.6 months in the SOF/VEL group. The cumulative incidence rates of decompensated events after 2 years were significantly higher in the control group (53.1%) than in the SOF/VEL group (14.5%; p < 0.001). A total of 27 patients died within 22.0 months in the control group, and three patients died within 25.6 months in the SOF/VEL group. The overall survival rates after 2 years were significantly lower in the control group (67.6%) than in the SOF/VEL group (91.3%; p = 0.010). A total of 13 patients in the control group developed HCC during 15.8 months, and 10 patients during 17.3 months in the SOF/VEL group. The HCC incidence rates after 2 years were 20.3% and 29.6% in the control and SOF/VEL groups, respectively, with no significant difference (p = 0.327). CONCLUSIONS: SOF/VEL therapy may suppress the development of decompensated events and improve the prognosis in decompensated cirrhotic patients; however, the incidence of HCC remains prevalent in these patients irrespective of SOF/VEL therapy.

Improved Liver Function After Sustained Virologic Response Enhanced Prognosis in Hepatitis C with Compensated Advanced Liver Fibrosis.

BACKGROUND AND AIM: Liver function can be improved in patients with chronic hepatitis C virus (HCV) infection who achieved sustained virologic response (SVR) with direct-acting antiviral (DAA) treatment. However, to our knowledge, the impact of liver function improvement after SVR on prognosis has not been investigated. METHODS: A total of 716 patients with chronic HCV infection and compensated advanced liver fibrosis who began receiving DAA treatment between September 2014 and August 2018 in 25 Japanese hospitals and achieved SVR were enrolled. RESULTS: The median age was 73 years, and 336 (47%) and 380 (53%) patients had albumin-bilirubin (ALBI) grade 1 and grade 2, respectively. Improvement to ALBI grade 1 at 1 year after the end of treatment (EOT) was observed in 76% of the patients with baseline ALBI grade 2. Among 380 patients with baseline ALBI grade 2, alanine aminotransferase (ALT) levels ≥ 40 U/L (p < 0.001) and modified ALBI (mALBI) grade 2a (p < 0.001) were significantly associated with improvement to ALBI grade 1 at 1 year after EOT in multivariate analysis. During the median observation period of 51.8 months, 4 and 10 patients with baseline ALBI grade 1 and 2, respectively, died. In patients with baseline ALBI grade 2, only the absence of improvement to ALBI grade 1 at 1 year after EOT was significantly associated with all-cause mortality in univariate analysis. CONCLUSIONS: Baseline ALT levels and mALBI grade were significantly associated with improvement in liver function after SVR. Patients whose liver function improved after SVR could have better prognosis.

Recycling endosomes attach to the trans-side of Golgi stacks in Drosophila and mammalian cells.

Historically, the trans-Golgi network (TGN) has been recognized as a sorting center of newly synthesized proteins, whereas the recycling endosome (RE) is a compartment where endocytosed materials transit before being recycled to the plasma membrane. However, recent findings revealed that both the TGN and RE connect endocytosis and exocytosis and, thus, are functionally overlapping. Here we report, in both Drosophila and microtubule-disrupted HeLa cells, that REs are interconvertible between two distinct states, namely Golgi-associated REs and free REs. Detachment and reattachment of REs and Golgi stacks are often observed, and newly synthesized glycosylphosphatidylinositol-anchored cargo protein but not vesicular stomatitis virus G protein is transported through these two types of RE. In plants, there are two types of TGN - Golgi-associated TGN and Golgi-independent TGN. We show that dynamics of REs in both Drosophila and mammalian cells are very similar compared with those of plant TGNs. And, together with the similarity on the molecular level, our results indicate that fly and mammalian REs are organelles that are equivalent to TGNs in plants. This suggests that the identities and functional relationships between REs and TGNs should be reconsidered.

Risk of hepatocellular carcinoma after sustained virologic response in hepatitis C virus patients without advanced liver fibrosis.

AIM: Hepatocellular carcinoma (HCC) after sustained virologic response (SVR) has been observed even in hepatitis C virus (HCV) patients without advanced liver fibrosis. Identifying predictors for HCC incidence in patients without advanced liver fibrosis will enable efficient post-SVR HCC surveillance. This study aimed to develop a scoring system to predict the incidence of HCC after SVR in HCV patients without advanced liver fibrosis. METHODS: A total of 1682 HCV patients without advanced liver fibrosis (defined as Fibrosis-4 index <3.25) with no history of HCC who initiated direct-acting antiviral treatment between September 2014 and October 2020 at 26 institutions, and achieved SVR24, were included. We divided 1682 patients into training (1122) and validation (560) cohorts. RESULTS: In the multivariate analysis, baseline age ≥ 65 years (p = 0.030), alanine aminotransferase (ALT) levels at SVR24 ≥ 30 U/l (p = 0.001), and α-fetoprotein (AFP) levels at SVR24 ≥ 5.0 ng/ml (p = 0.001) were independent predictors for HCC incidence in the training cohort. We developed a scoring system to predict HCC incidence after SVR24 using these three factors (1 point was added for each factor). The cumulative HCC incidence rates at 5 years were 7.1% in patients who scored 2 or 3, and no patients developed HCC in those who scored 0 in the validation cohort. CONCLUSIONS: Our scoring system using the three factors of baseline age, ALT levels at SVR, and AFP levels at SVR is useful for post-SVR HCC surveillance of patients without advanced liver fibrosis.

Prediction Model for Intrahepatic Distant Recurrence After Radiofrequency Ablation for Primary Hepatocellular Carcinoma 2 cm or Smaller.

BACKGROUND: Intrahepatic hepatocellular carcinoma (HCC) has a high recurrence rate after radiofrequency ablation (RFA). However, to date, no standalone predictive factors for intrahepatic distant recurrence after curative ablation have been reported. AIMS: The aim of this study was to investigate predictive factors for intrahepatic distant recurrence after curative treatment with RFA for HCCs. METHODS: This multicenter study consisted of 17 institutions that registered 821 patients. The risk factors for intrahepatic distant recurrence after complete ablation by RFA for primary HCC ≤ 2 cm in diameter were identified in a retrospectively collected training set (n = 636) and then validated in a prospectively collected validation set (n = 185). RESULTS: The cumulative intrahepatic distant and local recurrence rates (i.e., entire recurrence rate) in the training set were 23.6% and 53.7% at 1 and 3 years, respectively. The cumulative intrahepatic distant recurrence rates in the training set were 17.0% and 43.8% at 1 and 3 years, respectively. Multivariate analysis of the training set showed that tumor number and serum levels of α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) were independent risk factors for both entire recurrence and intrahepatic distant recurrence. Intrahepatic distant recurrence risk in both the training and validation cohorts was stratified using a scoring system with three factors: tumor number (single or multiple), AFP (< 10 ng/ml or ≥ 10 ng/ml), and DCP (< 50 mAU/ml or ≥ 50 mAU/ml). CONCLUSION: The scoring system composed of tumor number, AFP, and DCP is useful for classifying the risk of intrahepatic distant recurrence after curative ablation for HCC.

The Ventricular Hypokinesis at the Apical Pacing Site due to the Early Shortening and Rebound Stretch in a Case with Fontan Procedure.

The left ventricular (LV) apex is recommended as the first choice for positioning the epicardial pacing. We encountered a patient with congenital heart disease (CHD) showing hypokinesis of the LV apical pacing site after implantation of a pacemaker with epicardial leads. This phenomenon was revealed by the early shortening and systolic rebound stretch of the same lesion on two-dimensional speckle tracking echocardiography, which developed in the intraventricular dyssynchrony between the LV apex and base. Cardiac resynchronization therapy provided an excellent result around the hypokinetic lesion. It is wise to arrange detailed evaluations in each patient with complicated CHD, aiming at a successful treatment to enable ventricular synchronicity.

[A case of eosinophilic gastroenteritis caused after the use of Seprafilm®].

Eosinophilic gastroenteritis is a fairly uncommon condition. It has been suggested that allergic reactions may have played a role in the development of this illness. The case of a 66-year-old woman who had a total hysterectomy due to a right ovarian tumor is described here. At this operation, a sodium hyaluronate carboxymethylcellulose bioresorbable membrane (Seprafilm®) was used. She was admitted to our hospital 47 days after the operation with abdominal pain. Laboratory data indicated elevated WBC (29450/µl) and eosinophilia (69.2%), and CT scan showed thickening of intestinal wall and ascites around there. Ascites cytology showed a significant increase of eosinophils (94.0%). She began taking oral steroids after being diagnosed with eosinophilic gastroenteritis, and her symptoms improved quickly. Despite the fact that Seprafilm® was thought to be a reliable and safe tool, it was suggested that a foreign body reaction to Seprafilm® could lead to eosinophilic gastroenteritis.

Clinical course of hepatitis C virus-positive patients with decompensated liver cirrhosis in the era of direct-acting antiviral treatment.

AIM: The aim of the present study was to investigate the clinical course in hepatitis C virus (HCV)-positive patients with decompensated liver cirrhosis after direct-acting antivirals (DAAs) have been used for HCV infection. METHODS: This multicenter study prospectively analyzed a registered cohort composed of 73 HCV-positive patients with decompensated cirrhosis who attended our 11 institutions between January 2018 and July 2018. Prognoses, including changes in the liver reserve, hepatocellular carcinoma (HCC), decompensation events, and survival, were analyzed up to July 2020, as was the initiation of DAA treatment. RESULTS: Sixty-four (87.7%) and nine (12.3%) patients had Child-Pugh class (C-P) B and C at baseline, respectively. Within 2 years after enrollment, 17 patients (23.3%) received treatment with DAAs, and 31 patients (42.5%) developed uncontrolled HCC, switched to palliative care, or died. Patients who received DAA treatment were significantly younger and had significantly higher alanine aminotransferase levels and lower platelet counts than the patients who did not receive DAA treatment. The rates of overall survival, cumulative HCC occurrence, and cumulative hospitalization for any hepatic decompensation event at 2 years were 64.8%, 13.1%, and 65.6%, respectively. Overall survival was significantly shorter and the HCC occurrence and hospitalization rates were significantly higher in C-P C patients than in C-P B patients. CONCLUSIONS: Among HCV-positive patients with decompensated cirrhosis, approximately one-fourth received DAA treatment, but more than 40% of the patients lost the opportunity for treatment with DAAs.

Lower Serum Sodium Levels Are Associated with the Therapeutic Effect of Sorafenib on Hepatocellular Carcinoma.

BACKGROUND AND AIM: Although the serum sodium level has been reported to be a prognostic and predictive marker for the therapeutic effects of lung cancer and renal cell carcinoma treated with molecular targeted therapy, the serum sodium level has not been investigated in hepatocellular carcinoma (HCC) patients treated with sorafenib. The aim of our analysis was to assess the prognostic role of serum sodium levels in these patients. METHODS: We retrospectively analyzed 341 HCC patients treated with sorafenib between 2009 and 2012 in our hospital and other related institutions. RESULTS: A total of 178 patients were enrolled in this study. The median age was 72 years (44-88), and 148 patients (83%) were male. The median overall survival (OS) was 12.9 months, and the median time to progression (TTP) was 3.1 months. Hyponatremia (hazard ratio (HR) 1.78, 95% confidence interval (CI) 1.26-2.52), a lower sodium level (HR 1.57, 95% CI 1.07-2.80), and a high level of α-fetoprotein (AFP) (≥ 200 ng/mL) (HR 1.78, 95% CI 1.26-2.52) were independent prognostic factors for TTP. We also categorized the patients into three groups according to serum sodium and AFP levels: Group A (n = 39) (serum sodium > 140 mEq/L, AFP < 200 ng/mL), Group C (n = 58) (serum sodium ≤ 140 mEq/L, AFP ≥ 200 ng/mL), and Group B (n = 81) (other patients). Significantly longer TTP and OS were observed in the following order: Groups A, C, and B. CONCLUSION: Serum sodium levels are associated with the effectiveness of sorafenib. The serum sodium level can predict the therapeutic effect of sorafenib in advanced HCC patients.

Clinical outcomes of direct-acting antiviral treatments for patients with hepatitis C after hepatocellular carcinoma are equivalent to interferon treatment.

AIM: It remains unclear how direct-acting antiviral (DAA) treatments influence hepatocellular carcinoma (HCC) recurrence and survival in comparison with interferon (IFN). METHODS: In total, 338 patients with chronic hepatitis C virus (HCV) infection and previous HCC treatments who initiated IFN (N = 88, IFN group) or DAA treatment (N = 250, DAA group) from January 2005 to November 2017 at 23 hospitals and achieved sustained virologic response (SVR) were analyzed. Cumulative HCC recurrence and survival rates were compared between the two groups using propensity score (PS) matching. RESULTS: After PS matching, 63 patients were selected for each group. The cumulative HCC recurrence rates at 1 and 3 years were 20.6% and 34.6% in the IFN group and 19.2% and 43.0% in the DAA group, respectively; the difference in cumulative HCC recurrence rates between the two groups was not significant (P = 0.332). No significant differences in HCC recurrence patterns were observed between the two groups. Overall survival rates at 1 and 3 years were 100% and 96.6% in the IFN group and 100% and 96.4% in the DAA group, respectively; the difference in overall survival rates between the two groups was not significant (P = 0.132). No significant differences in HCC recurrence and overall survival rates were observed between the two groups in subgroup analyses of patients receiving curative treatment (liver resection or radiofrequency ablation) for the most recent HCC before HCV treatment. CONCLUSIONS: The recurrence rates and patterns of HCC and overall survival rates do not differ between SVR patients receiving IFN and DAA treatments.

Hepatocellular carcinoma occurrence does not differ between interferon-based and interferon-free treatment with liver histological assessment.

AIM: Several studies have recently reported that hepatocellular carcinoma (HCC) occurrence does not differ between hepatitis C virus patients receiving interferon (IFN)-based and IFN-free treatments considering the patients' backgrounds. However, liver fibrosis was not directly considered in these studies. METHODS: In total, 3972 patients without a history of HCC who started IFN-based or IFN-free treatment between August 2002 and April 2017 at 30 Japanese hospitals and achieved a sustained virologic response were included. Propensity score matching considering liver histology was performed. RESULTS: The median age and percentage of patients with advanced liver fibrosis (F3/4) were 58 years and 11.4% in the IFN-based group, and 68 years and 18.9% in the IFN-free group, respectively. The HCC occurrence rates at 1 year and 2 years were 0.4% and 1.1% in the IFN-based group, and 1.6% and 4.1% in the IFN-free group, respectively, and HCC occurrence in the IFN-free group was significantly higher than that in the IFN-based group (P < 0.001). The characteristics of the HCC occurrence patterns did not differ between the two groups. After propensity score matching, among 764 patients, the HCC occurrence rates at 1 year and 2 years were 0.5% and 1.9% in the IFN-based group and 1.1% and 3.0% in the IFN-free group, respectively, and no significant difference was observed between the two groups (P = 0.489). CONCLUSIONS: HCC occurrence in sustained virologic response patients does not differ between IFN-based and IFN-free treatment considering liver fibrosis stage. The degree of its progress at diagnosis does not differ between the two groups.

[Late Recurrence of Seminoma Diagnosed by Endoscopic Ultrasound-Guided Fine Needle Aspiration in a Retroperitoneal Lymph Node].

The patient was a 43-year-old man. At 30 years of age, he underwent high-inguinal orchiectomy for a right testicular tumor and was diagnosed with seminoma pT1N0M0. The patient had been followed without additional treatment and had dropped out 7 years after surgery. At 43 years of age, abdominal ultrasonography performed for screening revealed a swollen 4 cm-wide intra-abdominal lymph node, and he was referred to our department. Abdominal contrast-enhanced computed tomography (CT) showed a mass with a 5 cm-wide contrast effect that contacted the anterior surface of the inferior vena cava from the duodenum to the aortic bifurcation. Histological examination by trans-duodenal ultrasound-guided fineneedle aspiration suggested late recurrence of seminoma. After receiving three courses of BEP (bleomycin, etoposide, and platinum) therapy, the patient underwent laparoscopic lymphadenectomy. Pathological examination showed no residual tumor, and the patient was free of recurrence at 13 months after surgery.

[A Case of Advanced Adenosquamous Carcinoma of Pancreas with Conversion Surgery after Chemoradiotherapy Followed by Systemic Chemotherapy].

A man in his 60s with upper abdominal discomfort was referred to our hospital. CT scan revealed the 40 mm tumor in the body and tail of pancreas invading stomach wall. Solid soft tissue contact was also observed around celiac artery(CA)and common hepatic artery(CHA). EUS-FNA from pancreatic mass showed suspicion of adenosquamous carcinoma. We diagnosed it as pancreatic adenosquamous carcinoma, cT4N0M0, cStage Ⅲ. The patient received radiotherapy(46.8 Gy/26 Fr in total)combined with S-1. Although the primary lesion showed shrinkage, solid soft tissue around CA and CHA deteriorated. We judged the tumor unresectable, and the patient received systemic chemotherapy using gemcitabine(GEM). After 6 courses of GEM, solid soft tissue around CA and CHA almost disappeared. Based on these results, we performed distal pancreatectomy and partial gastrectomy 8 months after the initiation of the treatment. Pathological results showed adenosquamous carcinoma of the pancreas with Grade 2 response to the preoperative treatment. Although the tumor invaded into the gastric wall, R0 resection was achieved. The patient is alive with no recurrence a year and 4 months after the initiation of treatment and 8 months after resection.

Incidence and risk factors of hepatocellular carcinoma change over time in patients with hepatitis C virus infection who achieved sustained virologic response.

AIM: In patients with chronic hepatitis C, hepatocellular carcinoma (HCC) occurs at a certain frequency, even if a sustained virologic response (SVR) is achieved by antiviral treatment. Old age, liver fibrosis, and high post-treatment α-fetoprotein (AFP) level are typical risk factors of post-SVR HCC. We examined whether the frequencies and factors of HCC in patients with an SVR achieved from interferon treatment changed. Methods Among patients prospectively registered for pegylated interferon and ribavirin treatment, 2021 with an SVR without HCC development during the treatment period were followed up. The mean observation period was 49.5 ± 26.2 months. RESULTS: The multivariable Cox regression analysis showed that older age, diabetes mellitus, advanced liver disease, and higher post-treatment AFP level were the independent risk factors throughout the observation period. The annual occurrence rate of HCC was 0.74% in the third year, 0.54% in the fourth year, and 0.40% in the fifth year; it gradually decreased from the third year. Because the time course hazards for HCC changed at 48 months, we separately analyzed its risk factors before and after this change point. The multivariable Cox regression analysis showed that the four above-mentioned factors were significantly related to HCC development within 4 years. Conversely, the univariable Cox regression analysis only identified diabetes mellitus as a significant factor for HCC development after 4 years. CONCLUSION: The frequency of HCC in hepatitis C patients who achieved an SVR from interferon treatment decreased during the observation period, and its risk factors changed between the early and late periods.

CD14+ monocyte-derived galectin-9 induces natural killer cell cytotoxicity in chronic hepatitis C.

Natural killer (NK) cell activation is associated with both liver injury and persistent infection in chronic hepatitis C (CHC); however, the detailed mechanism of this activation has not yet been fully elucidated. Because galectin-9 (Gal-9) has been reported to be increased in the serum and liver tissue of CHC patients, we investigated the function of Gal-9 in NK cell activation in CHC. First, we evaluated the function of Gal-9 on NK cytotoxicity in vitro. Gal-9 treatment resulted in increased cytotoxicity of naïve NK cells, and the Gal-9-activated NK cells demonstrated cytotoxicity toward hepatoma cells and T cells. Additionally, coculturing peripheral blood mononuclear cells (PBMCs) with JFH-1/Huh7.5.1 cells increased both Gal-9 production and NK cell cytotoxicity. Next, we investigated the source of Gal-9 and the mechanism of Gal-9 production. Deletion of CD14+ monocytes from PBMCs resulted in reduced Gal-9 production in the coculture with JFH-1/Huh7.5.1 cells. Gal-9 production was driven by coculturing of PBMCs with apoptotic hepatocytes. Blocking integrin αv ß3 , a receptor for phosphatidylserine expressed on apoptotic cells, also resulted in decreased Gal-9 production. Finally, we found that serum Gal-9 levels were significantly higher in CHC patients than in healthy donors and patients who achieved sustained virologic response. Among CHC patients, serum Gal-9 levels were significantly higher in patients with elevated alanine aminotransferase (ALT) than in those with normal ALT. CONCLUSION: These results demonstrate that CD14+ monocyte-derived Gal-9 increases NK cell cytotoxicity in HCV infection, which might be associated with liver injury and persistent infection. (Hepatology 2017;65:18-31).

S100A8 Production in CXCR2-Expressing CD11b+Gr-1high Cells Aggravates Hepatitis in Mice Fed a High-Fat and High-Cholesterol Diet.

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease with a spectrum of presentations. S100A8 has been suggested to play a pivotal role as an endogenous immune-activator in inflammatory diseases. In this study, we investigated the involvement of S100A8 in the development of NAFLD. We used a diet model of NAFLD, in which mice were fed either a high-fat and high-cholesterol diet (HFHCD) or a normal diet (ND) as a control. We also assessed liver tissues from patients with NAFLD, including patients with nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). HFHCD-fed mice, but not ND-fed mice, developed steatohepatitis. S100A8 expression was significantly elevated in the livers of HFHCD-fed mice compared with the controls. S100A8 was exclusively expressed in CXCR2-expressing CD11b(+)Gr-1(high) cells, which significantly increased in the livers of HFHCD-fed mice. These cells were F4/80 negative and did not possess a suppressor function. TNF-α expression was enhanced by S100A8 in primary liver leukocytes or a hepatocyte cell line and significantly elevated in the livers of HFHCD-fed mice. TNF-α was primarily produced from CD11b(+)F4/80(+) cells in liver leukocytes in response to S100A8. TNF-α deficiency attenuated hepatitis in HFHCD-fed mice. S100A8 was significantly more expressed in the liver tissues of patients with NASH than in those of patients with NAFL. In conclusion, these results suggest that S100A8 is primarily produced from CXCR2-expressing CD11b(+)Gr-1(high) cells, and it upregulates TNF-α production in CD11b(+)F4/80(+) cells through cellular cross-talk, which is an important mechanism in the development of NAFLD.

Rubicon inhibits autophagy and accelerates hepatocyte apoptosis and lipid accumulation in nonalcoholic fatty liver disease in mice.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide. It encompasses a spectrum ranging from simple steatosis to fatty liver with hepatocellular injury, termed nonalcoholic steatohepatitis. Recent studies have demonstrated hepatic autophagy being impaired in NAFLD. In the present study, we investigated the impact of Rubicon, a Beclin1-interacting negative regulator for autophagosome-lysosome fusion, in the pathogenesis of NAFLD. In HepG2 cells, BNL-CL2 cells, and murine primary hepatocytes, Rubicon was posttranscriptionally up-regulated by supplementation with saturated fatty acid palmitate. Up-regulation of Rubicon was associated with suppression of the late stage of autophagy, as evidenced by accumulation of both LC3-II and p62 expression levels as well as decreased autophagy flux. Its blockade by small interfering RNA attenuated autophagy impairment and reduced palmitate-induced endoplasmic reticulum stress, apoptosis, and lipid accumulation. Rubicon was also up-regulated in association with autophagy impairment in livers of mice fed a high-fat diet (HFD). Hepatocyte-specific Rubicon knockout mice generated by crossing Rubicon floxed mice with albumin-Cre transgenic mice did not produce any phenotypes on a normal diet. In contrast, on an HFD, they displayed significant improvement of both liver steatosis and injury as well as attenuation of both endoplasmic reticulum stress and autophagy impairment in the liver. In humans, liver tissues obtained from patients with NAFLD expressed significantly higher levels of Rubicon than those without steatosis. CONCLUSION: Rubicon is overexpressed and plays a pathogenic role in NAFLD by accelerating hepatocellular lipoapoptosis and lipid accumulation, as well as inhibiting autophagy. Rubicon may be a novel therapeutic target for regulating NAFLD development and progression. (Hepatology 2016;64:1994-2014).

Signal transducer and activator of transcription 5 plays a crucial role in hepatic lipid metabolism through regulation of CD36 expression.

AIM: Liver-specific signal transducer and activator of transcription (STAT)5-deficient mice (STAT5KO) show lipid accumulation in the liver. We investigated the role of hepatic STAT5 in lipid metabolism in vitro and in vivo. METHODS AND RESULTS: High expression of CD36, one of the receptors for free fatty acids, is associated with a high concentration of hepatic triglyceride (TG) in STAT5KO mice. Peroxisome proliferator-activated receptor (PPAR)γ, one of the regulatory factors of CD36, was upregulated and microRNA (miR)-20b was downregulated in STAT5KO mice. Reporter assays revealed direct regulation involving miR-20b and the 3'-untranslated region of CD36 mRNA. Treatment with free fatty acids enhanced accumulation of TG in STAT5-deleted hepatoma cells, and this was partially canceled by introduction of siRNA for PPARγ and/or pre-miR-20b through inhibition of CD36 expression. In vivo, STAT5/CD36 double knockout mice displayed hepatic TG was decreased compared to STAT5KO mice and it was also reduced by treatment with PPARγ antagonists, GW9662, and/or pre-miR-20b. CONCLUSIONS: Signal transducer and activator of transcription 5 plays an important role in hepatic fat metabolism through regulation of CD36, and is a potential therapeutic candidate for liver steatosis.