The ceramide transport protein CERT is involved in alkylacylglycerol transfer from the ER to the Golgi for the biosynthesis of ether phospholipid.

Ether phospholipids are synthesized by a series of enzymes localized in peroxisomes, the endoplasmic reticulum (ER), and the Golgi apparatus. During this process, the lipid intermediate alkylacylglycerol (AAG) synthesized in the ER is transferred from the site of its synthesis to the Golgi apparatus. In this study, we determined whether ceramide transport protein (CERT) is a candidate for AAG transfer. A lipid transfer assay revealed that CERT can mediate AAG transfer between phospholipid liposomes. AAG transport activity was markedly inhibited by the CERT inhibitor HPA-12 and reduced when the lipid transport domain of CERT was deleted. Suppression of CERT in HEK293 cells resulted in increased levels of plasmanyl-PC, which is synthesized by the ER-residing choline/ethanolamine phosphotransferase 1 (CEPT1). The mRNA levels and enzymatic activity of plasmanyl-PC synthesizing enzymes were not increased in CERT-deficient cells, indicating that the increase in plasmanyl-PC results from AAG accumulation in the ER. Re-introduction of CERT into CERT-deficient cells caused a decrease in plasmanyl-PC. Taken together, our findings suggest for the first time that CERT is involved in the transfer of AAG from the ER to the Golgi apparatus and plays a role in the biosynthesis of ether phospholipids.

Effect of pulmonary vein isolation on the relationship between left atrial reverse remodeling and sympathetic nerve activity in patients with atrial fibrillation.

PURPOSE: Catheter ablation (CA) to isolate the pulmonary vein, which is an established treatment for atrial fibrillation (AF), is associated with left atrium reverse remodeling (LARR). The intrinsic cardiac autonomic nervous system includes the ganglion plexi adjacent to the pulmonary vein in the left atrium (LA). However, little is known about the effect of CA on the relationship between LARR and sympathetic nerve activity in patients with AF. METHODS: This study enrolled 22 AF patients with a normal left ventricular ejection fraction (LVEF) aged 64.6 ± 12.9 years who were scheduled for CA. Sympathetic nerve activity was evaluated by direct recording of muscle sympathetic nerve activity (MSNA) before and 12 weeks after CA. Blood pressure, heart rate (HR), HR variability, and echocardiography were also measured. RESULTS: The heart rate increased significantly after CA (63 ± 10.9 vs. 70.6 ± 7.7 beats/min, p < 0.01), but blood pressure did not change. A high frequency (HF) and low frequency (LF) of HR variability decreased significantly after ablation, but no significant change in LF/HF was observed. CA significantly decreased MSNA (38.9 ± 9.9 vs. 28 ± 9.1 bursts/min, p < 0.01). Moreover, regression analysis revealed a positive correlation between the percentage change in MSNA and the LA volume index (r = 0.442, p < 0.05). CONCLUSIONS: Our results show that CA for AF reduced MSNA and the decrease was associated with the LA volume index in AF patients with a normal LVEF. These findings suggest that LARR induced by CA for AF decrease sympathetic nerve activity.

Metabolic changes induced by TGF-ß1 via reduced expression of phosphatidylserine decarboxylase during myofibroblast transition.

Metabolic alteration is increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types, and metabolically targeted therapies could become important strategies for reducing fibrosis. In present study, target enzymes that are involved in changes in phospholipid metabolism during fibroblast-to-myofibroblast transition induced by transforming growth factor beta 1 (TGF-ß1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-ß1 stimulation, 17 lipids decreased and 17 increased. The latter included the phospholipids phosphatidylcholine (PC), phosphatidylserine (PS), and phosphatidylethanolamine (PE). Furthermore, among the rate-limiting enzymes that regulate these phospholipids, phosphatidylserine decarboxylase (PISD), which controls conversion of PS to PE and is localized in mitochondria, decreased in response to TGF-ß1. Knockdown of PISD alone without TGF-ß1 stimulation increased expression of α-smooth muscle actin mRNA and production of total collagen. Taken together, these results indicate that PISD is involved in the mechanism of fibrogenesis by regulating phospholipid metabolism.

Differential contributions of choline phosphotransferases CPT1 and CEPT1 to the biosynthesis of choline phospholipids.

Choline phospholipids (PLs) such as phosphatidylcholine (PC) and 1-alkyl-2-acyl-sn-glycerophosphocholine are important components for cell membranes and also serve as a source of several lipid mediators. These lipids are biosynthesized in mammals in the final step of the CDP-choline pathway by the choline phosphotransferases choline phosphotransferase 1 (CPT1) and choline/ethanolamine phosphotransferase 1 (CEPT1). However, the contributions of these enzymes to the de novo biosynthesis of lipids remain unknown. Here, we established and characterized CPT1- and CEPT1-deficient human embryonic kidney 293 cells. Immunohistochemical analyses revealed that CPT1 localizes to the trans-Golgi network and CEPT1 to the endoplasmic reticulum. Enzyme assays and metabolic labeling with radiolabeled choline demonstrated that loss of CEPT1 dramatically decreases choline PL biosynthesis. Quantitative PCR and reintroduction of CPT1 and CEPT1 revealed that the specific activity of CEPT1 was much higher than that of CPT1. LC-MS/MS analysis of newly synthesized lipid molecular species from deuterium-labeled choline also showed that these enzymes have similar preference for the synthesis of PC molecular species, but that CPT1 had higher preference for 1-alkyl-2-acyl-sn-glycerophosphocholine with PUFA than did CEPT1. The endogenous level of PC was not reduced by the loss of these enzymes. However, several 1-alkyl-2-acyl-sn-glycerophosphocholine molecular species were reduced in CPT1-deficient cells and increased in CEPT1-deficient cells when cultured in 0.1% FBS medium. These results suggest that CEPT1 accounts for most choline PL biosynthesis activity, and that both enzymes are responsible for the production of different lipid molecular species in distinct organelles.

Locations and contributions of the phosphotransferases EPT1 and CEPT1 to the biosynthesis of ethanolamine phospholipids.

The final step of the CDP-ethanolamine pathway is catalyzed by ethanolamine phosphotransferase 1 (EPT1) and choline/EPT1 (CEPT1). These enzymes are likely involved in the transfer of ethanolamine phosphate from CDP-ethanolamine to lipid acceptors such as 1,2-diacylglycerol (DAG) for PE production and 1-alkyl-2-acyl-glycerol (AAG) for the generation of 1-alkyl-2-acyl-glycerophosphoethanolamine. Here, we investigated the intracellular location and contribution to ethanolamine phospholipid (EP) biosynthesis of EPT1 and CEPT1 in HEK293 cells. Immunohistochemical analyses revealed that EPT1 localizes to the Golgi apparatus and CEPT1 to the ER. We created EPT1-, CEPT1-, and EPTI-CEPT1-deficient cells, and labeling of these cells with radio- or deuterium-labeled ethanolamine disclosed that EPT1 is more important for the de novo biosynthesis of 1-alkenyl-2-acyl-glycerophosphoethanolamine than is CEPT1. EPT1 also contributed to the synthesis of PE species containing the fatty acids 36:1, 36:4, 38:5, 38:4, 38:3, 40:6, 40:5, and 40:4. In contrast, CEPT1 was important for PE formation from shorter fatty acids such as 32:2, 32:1, 34:2, and 34:1. Brefeldin A treatment did not significantly affect the levels of the different PE species, indicating that the subcellular localization of the two enzymes is not responsible for their substrate preferences. In vitro enzymatic analysis revealed that EPT1 prefers AAG 16-20:4 > DAG 18:0-20:4 > DAG 16:0-18:1 = AAG 16-18:1 as lipid acceptors and that CEPT1 greatly prefers DAG 16:0-18:1 to other acceptors. These results suggest that EPT1 and CEPT1 differ in organelle location and are responsible for the biosynthesis of distinct EP species.

Characterization of glycerophosphodiesterase 4-interacting molecules Gαq/11 and Gß, which mediate cellular lysophospholipase D activity.

We previously purified lysophospholipase D (lysoPLD), which hydrolyzes lysophosphatidylcholine (lysoPC) to lysophosphatidic acid (LPA), from rat brain and identified the heterotrimeric G protein subunits Gαq and Gß1 in the lysoPLD active fractions. Tag-affinity purified Gαq exhibits lysoPLD activity but a mutant that affected cellular localization or interaction with the Gß subunit reduced lysoPLD activity. Size exclusion chromatography revealed that active lysoPLD is a much higher molecular mass complex than is heterotrimeric G protein, suggesting the presence of other components. Liquid chromatography-tandem mass spectrometry of lysoPLD purified from rat brain identified glycerophosphodiesterase 4 (GDE4), recently reported as lysoPLD, in the same fraction as G proteins. The overexpressed and tag-purified Gαq fractions, which exhibit lysoPLD activity, contained GDE4. Exogenously expressed GDE4 was co-immunoprecipitated with endogenous Gαq and Gß and exhibited high lysoPLD activity. The results of confocal microscopy and cell fractionation experiments indicated that exogenously expressed GDE4 in cells mainly localized at the endoplasmic reticulum and partially co-localized with Gαq protein at the plasma membrane. Proteinase K protection assay results suggested that the catalytic domain of GDE4 faces the lumen/extracellular space. Mutations at the conserved amino acids in the C-terminus cytoplasmic regions amongst GDE1, 4 and 7, dramatically suppressed GDE4 enzyme activities. When both the Gαq and Gα11 genes in Neuro2A cells were disrupted using the CRISPR-Cas9 system, endogenous lysoPLD activity was partially reduced but rescued by overexpression of Gαq. These results suggest that GDE4 is a new effector of G protein signaling that produces bioactive phospholipid LPA and/or modulates membrane homeostasis.

Effects of the differential expression of ZO-1 and ZO-2 on podocyte structure and function.

Glomerular podocytes in the kidney originate from columnar epithelial cells possessing tight junctions. During podocyte differentiation, tight junctions are replaced by slit diaphragms, which are formed between foot processes and function as a blood filtration barrier. Although the expression of most tight junction components is suppressed during podocyte differentiation, several components, including ZO-1 and ZO-2, are consistently expressed. We recently showed that podocyte-specific deletion of ZO-1 gene impaired slit diaphragm formation, leading to proteinuria and glomerular sclerosis. Here, we address the relevance of ZO-2, whose sequence is highly similar to ZO-1, in the maintenance of the structure and function of podocytes. In glomerular development, the spatiotemporal expression of ZO-2 was similar to that of ZO-1 until the capillary loop stage. Subsequently, the distribution patterns of ZO-1 and ZO-2 diverged at the maturation stage, when slit diaphragms are formed. This divergence could partly rely on the ability of ZO-2 to interact with the slit diaphragm membrane proteins. Podocyte-specific deletion of the ZO-2 gene did not cause overt defects; however, double knockout of ZO-1 and ZO-2 genes accelerated the defects observed in ZO-1 knockout mice. These results suggest that ZO-2 plays supportive roles in the ZO-1-dependent regulation of podocyte filtration barrier.

Comparison of 8- and 10-mm diameter fully covered self-expandable metal stents: A multicenter prospective study in patients with distal malignant biliary obstruction.

OBJECTIVES: The time to recurrent biliary obstruction (TRBO) of unresectable distal malignant biliary obstruction is generally thought to be longer when a self-expandable metal stent (SEMS) with a thicker inner diameter is used for drainage, but the dependence on the inner diameter using a fully covered SEMS (FCSEMS) is uncertain. The objective of this multicenter prospective study was to compare TRBO and adverse events, such as cholecystitis and pancreatitis, in treatment of patients with unresectable malignant biliary obstruction using 8- and 10-mm diameter FCSEMS. METHODS: Eighteen tertiary-care centers participated in the study. Patients were allocated to the 8- and 10-mm diameter groups. TRBO, non-inferiority of the 8-mm FCSEMS, overall survival time, frequency and type of adverse events, and non-recurrent biliary obstruction (RBO) rate at the time of death were compared between the two groups. RESULTS: Median TRBO did not differ significantly between the 8-mm (n = 102) and 10-mm (n = 100) groups (275 vs 293 days, P = 0.971). The hazard ratio of the 8- to 10-mm groups was 0.90 (80% confidence interval, 0.77-1.04; upper limit lower than the acceptable hazard ratio [1.33] of the null hypothesis). Based on these findings, the 8-mm diameter stent was determined to be non-inferior to the 10-mm diameter stent. Survival time, incidence of adverse events and non-RBO rate at the time of death did not differ significantly between the two groups. CONCLUSIONS: Time to RBO with an 8-mm diameter FCSEMS was non-inferior to that with a 10-mm diameter FCSEMS. This finding is important for development of future SEMS.

EPT1 (selenoprotein I) is critical for the neural development and maintenance of plasmalogen in humans.

Ethanolamine phosphotransferase (EPT)1, also known as selenoprotein 1 (SELENOI), is an enzyme that transfers phosphoethanolamine from cytidine diphosphate-ethanolamine to lipid acceptors to produce ethanolamine glycerophospholipids, such as diacyl-linked phosphatidylethanolamine (PE) and ether-linked plasmalogen [1-alkenyl-2-acyl-glycerophosphoethanolamine (plasmenyl-PE)]. However, to date there has been no analysis of the metabolomic consequences of the mutation of EPT1 on the concentration of ethanolamine glycerophospholipids in mammalian cells. We studied a patient with severe complicated hereditary spastic paraplegia, sensorineural-deafness, blindness, and seizures. Neuroimaging revealed hypomyelination, followed by brain atrophy mainly in the cerebellum and brainstem. Using whole exome sequencing, we identified a novel EPT1 mutation (exon skipping). In vitro EPT activity, as well as the rate of biosynthesis of ethanolamine glycerophospholipids, was markedly reduced in cultures of the patient's skin fibroblasts. Quantification of phospholipids by LC-MS/MS demonstrated reduced levels of several PE species with polyunsaturated fatty acids, such as 38:6, 38:4, 40:6, 40:5, and 40:4. Notably, most plasmenyl-PE species were significantly decreased in the patient's cells, whereas most plasmanylcholine [1-alkyl-2-acyl-glycerophosphocholine (plasmanyl-PC)] species were increased. Similar findings regarding decreased plasmenyl-PE and increased plasmanyl-PC were obtained using EPT1-KO HeLa cells. Our data demonstrate for the first time the indispensable role of EPT1 in the myelination process and neurodevelopment, and in the maintenance of normal homeostasis of ether-linked phospholipids in humans.

Significance of SYT8 For the Detection, Prediction, and Treatment of Peritoneal Metastasis From Gastric Cancer.

OBJECTIVE: To develop novel diagnostic and therapeutic targets specific for peritoneal metastasis of gastric cancer (GC). BACKGROUND: Advanced GC frequently recurs because of undetected micrometastases even after curative resection. Peritoneal metastasis has been the most frequent recurrent pattern after gastrectomy and is incurable. METHODS: We conducted a recurrence pattern-specific transcriptome analysis in an independent cohort of 16 patients with stage III GC who underwent curative gastrectomy and adjuvant S-1 for screening candidate molecules specific for peritoneal metastasis of GC. Next, another 340 patients were allocated to discovery and validation sets (1:2) to evaluate the diagnostic and predictive value of the candidate molecule. The results of quantitative reverse-transcription PCR and immunohistochemical analysis were correlated with clinical characteristics and survival. The effects of siRNA-mediated knockdown on phenotype and fluorouracil sensitivity of GC cells were evaluated in vitro, and the therapeutic effects of siRNAs were evaluated using a mouse xenograft model. RESULTS: Synaptotagmin VIII (SYT8) was identified as a candidate biomarker specific to peritoneal metastasis. In the discovery set, the optimal cut-off of SYT8 expression was established as 0.005. Expression levels of SYT8 mRNA in GC tissues were elevated in the validation set comprising patients with peritoneal recurrence or metastasis. SYT8 levels above the cut-off value were significantly and specifically associated with peritoneal metastasis, and served as an independent prognostic marker for peritoneal recurrence-free survival of patients with stage II/III GC. The survival difference between patients with SYT8 levels above and below the cut-off was associated with patients who received adjuvant chemotherapy. Inhibition of SYT8 expression by GC cells correlated with decreased invasion, migration, and fluorouracil resistance. Intraperitoneal administration of SYT8-siRNA inhibited the growth of peritoneal nodules and prolonged survival of mice engrafted with GC cells. CONCLUSIONS: SYT8 represents a promising target for the detection, prediction, and treatment of peritoneal metastasis of GC.

Role of neuronal nitric oxide synthase in slowly progressive dopaminergic neurodegeneration in the Zitter rat.

Neuronal nitric oxide synthase (nNOS) is involved in nigrostriatal dopaminergic (DA) neurodegeneration. However, little is known about the distribution patterns and functions of nNOS in slowly progressive DA neurodegeneration. Here we describe the spatiotemporal change in nNOS expression over the course of neurodegeneration and the effect of short- or long-term treatment with the nNOS inhibitor, 7-nitroindazole (7-NI), in zitter (zi/zi) rats. In the substantia nigra pars compacta (SNc), nNOS expression was significantly increased with progression of neurodegeneration. nNOS-immunoreactive (ir) cells were in the vicinity of tyrosine hydroxylase-ir (TH-ir) DA neurons, and some of these cells were also positive for calbindin. nNOS in the caudate-putamen (CPu) showed little difference during progression of neurodegeneration. However, immunoelectron microscopic analysis revealed that abundant TH-ir fibers in the CPu were degenerated due to compression by vacuoles that contained swollen neuronal and glial elements. Additionally, lipid peroxidation as a marker of membrane oxidation was significantly increased in zi/zi rats. Short-term 7-NI treatment attenuated the increase in lipid peroxidation and inhibited the vacuolation in the CPu. Moreover, long-term 7-NI treatment significantly protected TH-ir neurons in the SNc, and TH-ir fibers and DA contents in the CPu. These results show that nNOS exacerbates slowly progressive DA neurodegeneration, and the neuroprotective effects of 7-NI may result from suppression of membrane oxidation that causes abnormal membrane structures in zi/zi rats.

Significant Association Between Coronary Artery Low-Attenuation Plaque Volume and Apnea-Hypopnea Index, But Not Muscle Sympathetic Nerve Activity, in Patients With Obstructive Sleep Apnea Syndrome.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with augmented sympathetic nerve activity and cardiovascular diseases. However, the interaction between coronary artery plaque characteristics and sympathetic nerve activity remains unclear. The purpose of this study was to clarify the relationships between coronary artery plaque characteristics, sleep parameters and single- and multi-unit muscle sympathetic nerve activity (MSNA) in OSAS patients. Methods and Results: A total of 32 OSAS patients who underwent full-polysomnography participated in this study. The coronary plaque volume was calculated with 320-slice coronary computed tomography (CT). Single- and multi-unit MSNA were obtained during the daytime within 1 week from full-polysomnography. Patients were divided into 2 groups according to their apnea-hypopnea index (AHI) score (mild-moderate group, AHI <30; and severe group, AHI ≥30). There were no group differences in risk factors for atherosclerosis; however, severe AHI patients showed significantly high single-unit MSNA, and low- and intermediate-attenuation plaque volumes. In regression analysis, the plaque volume of any CT value was not associated with single- or multi-unit MSNA; only AHI significantly correlated with low-attenuation plaque volume (R=0.52, P<0.05). CONCLUSIONS: Our findings provided the evidence that AHI is an independent predictor for low-attenuated, vulnerable plaque volume, but not daytime MSNA, in patients with OSAS.

Natural history of pancreatic cystic lesions: A multicenter prospective observational study for evaluating the risk of pancreatic cancer.

BACKGROUND AND AIM: The aim of this study is to elucidate the natural history of pancreatic cystic lesions (PCLs), including branch duct-type intraductal papillary mucinous neoplasm (BD-IPMN), via midterm follow-up analysis of a multicenter prospective observational study (NSPINAL study). METHODS: From July 2011 to October 2016, 881 patients with PCLs were enrolled in NSPINAL study, and 664 patients with > 12 months of follow up were analyzed. Every patient was asymptomatic, and endoscopic ultrasound was performed at the initial diagnosis to exclude high-risk individuals. Follow up included endoscopic ultrasound, computed tomography, or magnetic resonance imaging at least once a year. Serial morphological changes and the pancreatic cancer (PC) incidence, including malignant progression of PCLs, were evaluated. RESULTS: The 664 patients (358 men) were followed for a median of 33.5 months (interquartile range 29). The cyst and main pancreatic duct sizes were 16.6 ± 9.3 and 2.3 ± 1.0 mm, respectively. Morphologically, 518 cases were multilocular, 137 were unilocular, and 9 had a honeycomb pattern; 269 cases involved multifocal lesions. Ninety-six patients (14.5%) showed worsening progression on imaging. There were two resectable and four unresectable cases of pancreatic ductal adenocarcinoma and three cases of malignant BD-IPMN. The 3-year risk of developing PC was 1.2%. The standardized incidence ratio for PC among PCLs was 10.0 (95% confidence interval 3.5-16.5), and the standardized incidence ratio among BD-IPMN was 16.6 (95% confidence interval 5.1-28.1). Multivariate analysis showed that development of symptoms and worsening progression were significant predictors of PC. CONCLUSIONS: Malignant progression of PCLs, including PC development, is not uncommon. Patients with PCLs should be carefully monitored to detect pancreatic ductal adenocarcinoma at early stages.

Preoperative Albumin-Bilirubin Grade Predicts Recurrences After Radical Gastrectomy in Patients with pT2-4 Gastric Cancer.

BACKGROUND: The albumin-bilirubin (ALBI) score was initially developed for assessing liver dysfunction severity and was suggested to have prognostic value in patients with hepatocellular carcinoma. We aimed to evaluate the prognostic impact of ALBI grade in patients with advanced gastric cancer (GC) after radical gastrectomy. METHODS: This study included 283 patients who underwent radical gastrectomy for pT2-4 GC without preoperative treatment. ALBI was calculated as follows: (log10 bilirubin (µmol/L) × 0.66) + (albumin (g/L) × -0.0852) and categorized into grades 1 (≤-2.60), 2 (-2.60<, ≤-1.39) and 3 (-1.39<). RESULTS: The median ALBI score was -2.96, and a number of patients in ALBI grades 1, 2 and 3 were 228, 55 and 0, respectively. Patients with ALBI grade 2 had a lower administration rate of adjuvant chemotherapy than those with ALBI grade 1, whereas no significant differences were found in morbidity rate and disease stage. The ALBI grade 2 group was more likely to have shorter disease-specific and disease-free survival compared with the ALBI grade 1 group. Multivariable analysis identified ALBI grade 2 as an independent prognostic factor for disease-free survival (hazard ratio 1.97, 95% confidence interval 1.10-3.47, p = 0.0242). Survival differences between ALBI grade 1 and 2 groups were increased in the patient subset that received adjuvant chemotherapy. ALBI grade 2 was correlated with a shortened duration of administration of postoperative S-1 adjuvant. CONCLUSIONS: ALBI grade serves as a simple and promising predictive factor for disease-free and disease-specific survival in patients with pT2-4 GC after radical gastrectomy.

Perioperative Serum Carcinoembryonic Antigen Levels Predict Recurrence and Survival of Patients with Pathological T2-4 Gastric Cancer Treated with Curative Gastrectomy.

BACKGROUND/AIMS: Do serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 levels serve as prognostic indicators in patients with gastric cancer (GC)? This is a question that has long been disputed. The aim of this study was to evaluate the significance of perioperative serum levels of CEA and CA19-9 for predicting the recurrence and long-term survival after patients with pT2-4 GC undergo curative gastrectomy. METHODS: This study included 251 patients with radically resected pT2-4 GC without preoperative treatment. Associations between the preoperative and postoperative serum levels of CEA or CA19-9 and postoperative long-term outcomes and recurrence patterns were evaluated. RESULTS: Preoperative CEA >5.0 ng/mL was an independent prognostic factor of overall survival. Elevation of both preoperative CEA and CA19-9 levels showed no synergistic adverse effects on prognosis. Preoperative levels of these markers achieved superior predictive performance compared with the postoperative values. Adverse prognosis is significantly associated with persistent elevation of CEA levels before and after gastrectomy. Elevation of CEA levels, particularly at postoperative measurement, was significantly associated with hematogenous recurrence. CONCLUSION: Determination of perioperative CEA levels facilitated predictions of recurrence patterns and prognosis among patients with pT2-4 GC who underwent curative gastrectomy.

Randomised controlled trial of long-term maintenance corticosteroid therapy in patients with autoimmune pancreatitis.

OBJECTIVE: Corticosteroid has been established as the standard therapy for autoimmune pancreatitis (AIP), but the requirement for maintenance corticosteroid therapy is controversial. We conducted a randomised controlled trial to clarify the efficacy of maintenance corticosteroid therapy in patients with AIP. DESIGN: We conducted a multicentre, tertiary setting, randomised controlled trial. After the induction of remission with the initial oral prednisolone (PSL) treatment, maintenance therapy with PSL at 5-7.5 mg/day was continued for 3 years or withdrawn at 26 weeks. The primary endpoint was relapse-free survival over 3 years and the secondary endpoint was serious corticosteroid-related complications. All analyses were performed on an intention-to-treat basis. RESULTS: Between April 2009 and March 2012, 49 patients with AIP were randomly assigned to the maintenance therapy group (n=30) or the cessation group (n=19). Baseline characteristics were not different between the two groups. Relapses occurred within 3 years in 11 out of 19 (57.9%) patients assigned to the cessation group, and in 7 of 30 (23.3%) patients in the maintenance therapy group. The relapse rate over 3 years was significantly lower in the maintenance therapy group than that in the cessation group (p=0.011). The relapse-free survival was significantly longer in the maintenance therapy group than that in the cessation group (p=0.007). No serious corticosteroid-related complications requiring discontinuation of PSL were observed. CONCLUSIONS: Maintenance corticosteroid therapy for 3 years may decrease relapses in patients with AIP compared with those who discontinued the therapy at 26 weeks. TRIAL REGISTRATION NUMBER: UMIN000001818; Results.

StarD7 Protein Deficiency Adversely Affects the Phosphatidylcholine Composition, Respiratory Activity, and Cristae Structure of Mitochondria.

Phosphatidylcholine (PC) is a major phospholipid of mitochondria, comprising 40-50% of both the outer and the inner membranes. However, PC must be imported from its production organelles because mitochondria lack the enzymes essential for PC biosynthesis. In a previous study, we found that StarD7 mediates the intracellular transfer of PC to mitochondria. Therefore, in this study, we analyzed the contribution of StarD7 to the maintenance of mitochondrial phospholipid content and function using siRNA-mediated knockdown and knock-out (KO) of the StarD7 gene in HEPA-1 cells. Real time analysis of respiratory activity demonstrated that the oxygen consumption rate and activity of mitochondrial complexes were impaired in StarD7-KD cells. To confirm these results, we established StarD7-KO HEPA-1 cells by double nicking using CRISPR/Cas9n. As expected, StarD7-KD and -KO cells showed a significant reduction in mitochondrial PC content. The ATP level and growth rate of KO cells were notably lower compared with wild-type cells when cultured in glucose-free galactose-containing medium to force cells to rely on mitochondrial ATP production. In KO cells, the level of the MTCO1 protein, a primary subunit of complex IV, was reduced without a concomitant decrease in its mRNA, but the level was restored when StarD7-I was overexpressed. StarD7-KO cells showed impaired formation of the mitochondrial supercomplexes and exhibited a disorganized cristae structure, with no changes in optic atrophy 1 protein. These findings indicate that StarD7 plays important roles in maintaining the proper composition of mitochondrial phospholipids as well as mitochondrial function and morphogenesis.

FAM46C Serves as a Predictor of Hepatic Recurrence in Patients with Resectable Gastric Cancer.

BACKGROUND: Gastric cancer (GC) relapse can occur even if curative resection is achieved. Biomarkers predicting recurrence are needed to provide appropriate postoperative surveillance and perioperative therapeutic strategy. METHODS: A global expression profiling was performed using tissues from GC patients with synchronous liver-confined metastasis. Family with sequence similarity 46, member C (FAM46C), was identified as a candidate biomarker. mRNA expression analysis, direct nucleotide sequencing, bisulfite sequencing and copy number assays for FAM46C were performed with eleven GC cell lines. Expression levels of FAM46C in primary GC tissues from 129 patients who underwent curative GC resection were determined and correlated with clinicopathological factors, including postoperative outcome. RESULTS: Levels of FAM46C mRNA differed among GC cell lines. Point mutations in FAM46C were detected in five GC cell lines accompanied with reduced FAM46C transcription. No hypermethylation was found in the promoter region of FAM46C. Copy number alterations were found in six GC cell lines with differing FAM46C transcription levels. Reduced FAM46C mRNA expression levels were detected in 117 (91 %) GC specimens compared with adjacent noncancerous tissues. Low FAM46C expression levels were significantly associated with larger macroscopic GC tumor sizes. The low FAM46C expression group was likely to have shorter disease-free survival than the high group and low FAM46C level was identified as an independent risk factor for recurrence after curative resection. FAM46C expression levels were low in all cases that were later found to have hepatic recurrence. CONCLUSIONS: Reduced GC expression of FAM46C is a potential biomarker to predict hepatic recurrence after curative gastrectomy.

Proposal of the Coagulation Score as a Predictor for Short-Term and Long-Term Outcomes of Patients with Resectable Gastric Cancer.

BACKGROUND: Systemic hemostasis and thrombosis activation has been implicated in tumor progression and metastasis. This study aimed to investigate the use of coagulation factors as a novel prediction method for postoperative outcomes after curative gastrectomy in patients with stage II/III gastric cancer (GC). METHODS: Overall, 126 patients with stage II/III GC who underwent gastrectomy between May 2003 and February 2016 were eligible for inclusion in the study. We retrospectively evaluated the predictive value of preoperative platelet count and plasma fibrinogen and d-dimer levels, and coagulation score (0: fibrinogen and d-dimer both below upper limits; 1: either fibrinogen or d-dimer over upper limits; 2: both fibrinogen and d-dimer over upper limits) for short- and long-term outcomes. RESULTS: Postoperative complications were significantly more frequent in patients with elevated preoperative d-dimer levels compared with those with normal d-dimer levels (26 vs. 10 %; p = 0.032). The prevalence of postoperative complications showed a stepwise increase in proportion to the coagulation score. Patients with a coagulation score of 2 had significantly larger tumors (p = 0.013) and significantly greater intraoperative blood loss (p = 0.004) than those who scored 0 or 1. Coagulation score showed the highest values distinguished high-risk patients in overall and disease-free survival, and a coagulation score of 2 was an independent prognostic factor for recurrence. Patients with a coagulation score of 2 experienced a significantly higher prevalence of liver metastasis as an initial recurrence than those who scored 0 or 1 (p = 0.019). CONCLUSIONS: The coagulation score is a simple and promising predictor for postoperative complications and recurrence after gastrectomy in stage II/III GC patients.

Downregulation of GPR155 as a prognostic factor after curative resection of hepatocellular carcinoma.

BACKGROUND: Molecular biomarkers capable of predicting recurrence patterns and prognosis are helpful for risk stratification and providing appropriate treatment to patients with hepatocellular carcinoma (HCC). In this study, we focused on G protein-coupled receptor 155 (GPR155), a cell surface signaling protein, as a candidate biomarker. METHODS: We analyzed GPR155 expression, DNA methylation, and copy number in HCC cell lines. The clinical significance of GPR155 expression was evaluated using 144 pairs of surgically resected liver and normal tissues with subgroup analysis based on hepatitis virus infection. RESULTS: GPR155 mRNA expression levels were differential and were decreased in 89% of HCC cell lines. No DNA methylation was detected, whereas copy number alterations were present in five (56%) HCC cell lines. GPR155 mRNA expression level was independent of background liver status and significantly lower in HCC tissues than corresponding normal liver tissues. The expression patterns of GPR155 protein by immunohistochemical staining were significantly associated with those of GPR155 mRNA. Downregulation of GPR155 was significantly associated with more aggressive HCC phenotypes including high preoperative α-fetoprotein, poor differentiation, serosal infiltration, vascular invasion, and advanced disease stage. Patients with downregulation of GPR155 were more likely to have worse prognosis after curative resection irrespective of hepatitis virus infection. Patients who experienced extrahepatic (distant) recurrences had significantly lower GPR155 expression than those with intrahepatic (liver confined) recurrences. CONCLUSIONS: Downregulation of GPR155 may serve as a prognosticator that also predicts initial recurrence sites independent of hepatitis virus infection.