Autophagy inhibition suppresses hormone production and cell growth in pituitary tumor cells: A potential approach to pituitary tumors

Pituitary tumors (PTs) represent about 10% of all intracranial tumors, and most are benign. However, some PTs exhibit continued growth despite multimodal therapies. Although temozolomide (TMZ), an alkylating chemotherapeutic agent, is a first-line medical treatment for aggressive PTs, some PTs are resistant to TMZ. Existing literature indicated the involvement of autophagy in cell growth in several types of tumors, including PTs, and autophagy inhibitors have anti-tumor effects. In this study, the expression of several autophagy-inducible genes, including Atg3, Beclin1, Map1lc3A, Map1lc3b, Ulk1, Wipi2, and Tfe3 in two PT cell lines, the mouse corticotroph AtT-20 cells and the rat mammosomatotroph GH4 cells were identified. Down regulation of Tfe3, a master switch of basal autophagy, using RNA interference, suppressed cell proliferation in AtT-20 cells, suggesting basal autophagy contributes to the maintenance of cellular functions in PT cells. Expectedly, treatment with bafilomycin A1, an autophagy inhibitor, suppressed cell proliferation, increased the cleavage of PARP1, and reduced ACTH production in AtT-20 cells. Treatment with two additional autophagy inhibitors, chloroquine (CQ) and monensin, demonstrated similar effects on cell proliferation, apoptosis, and ACTH production in AtT-20 cells. Also, treatment with CQ suppressed cell proliferation and growth hormone production in GH4 cells. Moreover, the combination of CQ and TMZ had an additive effect on the inhibition of cell proliferation in AtT-20 and GH4 cells. The additive effect of anti-cancer drugs such as CQ alone or in combination with TMZ may represent a novel therapeutic approach for PTs, in particular tumors with resistance to TMZ.

Copulation Duration and Sperm Precedence with Reference to Larval Diapause Induction in Monochamus alternatus Hope (Coleoptera: Cerambycidae)

Adults of the pine sawyer Monochamus alternatus are the primary vector of Bursaphelenchus xylophilus, the causative agent of pine wilt disease. A sawyer subspecies in Taiwan (abbreviated 'T') has two generations a year (bivoltinism) due to facultative diapause, whereas another subspecies in Japan (abbreviated 'J') has a one- or two-year life cycle due to obligate diapause. T, with two infection periods a year, will cause more severe disease epidemics than J if it is introduced into Japan. Inter-subspecies hybridization may inhibit the expression of bivoltinism because many F1 hybrids induce diapause. To predict the effects of introducing T into Japan, the present study investigated copulation duration and late-male sperm precedence to fertilize eggs. The results indicated that a single copulation for more than 65 s supplied sufficient sperm to fertilize a lifetime production of eggs. The incidence of larval diapause was 0.15 for the offspring of T females that mated with a T male and increased to 0.292-0.333 after remating with a J male, while the incidence of larval diapause was 0.900-1.000 for hybrids from T females mated with a J male. Consequently, the estimated proportion of second-male sperm used by T females was 0.185-0.217. The effects of introducing T populations into Japan on the severity of disease epidemics were also discussed.

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.

Relationships between muscle sympathetic nerve activity and novel indices of arterial stiffness using single oscillometric cuff in patients with hypertension

The arterial velocity pulse index (AVI) and arterial pressure-volume index (API) have been proposed as new arterial stiffness indices that can be measured using an oscillometric cuff. Sympathetic nerve activity (SNA) contributes to arterial stiffness via increasing vascular smooth muscle tone. However, the associations between SNA and the AVI or API are not understood. The purpose of this study was to evaluate the relationships between muscle sympathetic nerve activity (MSNA) and the AVI or API in healthy individuals and patients with hypertension (HT). Forty healthy individuals (40.1 ± 15.2 years, 8 females) (healthy group) and 40 patients with HT (60.2 ± 13.6, 18 females) (HT group) were included in this study. The AVI, API, MSNA, beat-by-beat blood pressure, and heart rate were recorded simultaneously. The AVI and API were higher in the HT group than in the healthy group (AVI, 26.1 ± 7.6 vs. 16.5 ± 4.0, p < 0.001; API, 31.2 ± 8.6 vs. 25.5 ± 7.2, p = 0.002). MSNA in the HT group was also higher than in the healthy group (p < 0.001). MSNA was correlated with the AVI, but not with the API, in both the healthy group (R = 0.52, p = 0.001) and HT group (R = 0.57, p < 0.001). MSNA was independently correlated with the AVI in multivariate analysis (ß = 0.34, p = 0.001). In conclusion, AVI, obtained by a simple and less user-dependent method, was related to the MSNA in healthy individuals and patients with HT.

Different Responses of Muscle Sympathetic Nerve Activity to Dapagliflozin Between Patients With Type 2 Diabetes With and Without Heart Failure

Background Sodium-glucose cotransporter 2 inhibitors improve cardiovascular outcomes in patients with diabetes with and without heart failure (HF). However, their influence on sympathetic nerve activity (SNA) remains unclear. The purpose of this study was to evaluate the effect of sodium-glucose cotransporter 2 inhibitors on SNA and compare the responses of SNA to sodium-glucose cotransporter 2 inhibitors in patients with type 2 diabetes with and without HF. Methods and Results Eighteen patients with type 2 diabetes, 10 with HF (65.4±3.68 years) and 8 without HF (63.3±3.62 years), were included. Muscle SNA (MSNA), heart rate, and blood pressure were recorded before and 12 weeks after administration of dapagliflozin (5 mg/day). Sympathetic and cardiovagal baroreflex sensitivity were simultaneously calculated. Brain natriuretic peptide level increased significantly at baseline in patients with HF than those without HF, while MSNA, blood pressure, and hemoglobin A1c did not differ between the 2 groups. Fasting blood glucose and homeostatic model assessment of insulin resistance did not change in either group after administering dapagliflozin. MSNA decreased significantly in both groups. However, the reduction in MSNA was significantly higher in patients with HF than patients with non-HF (-20.2±3.46 versus -9.38±3.65 bursts/100 heartbeats; P=0.049), which was concordant with the decrease in brain natriuretic peptide. Conclusions Dapagliflozin significantly decreased MSNA in patients with type 2 diabetes regardless of its blood glucose-lowering effect. Moreover, the reduction in MSNA was more prominent in patients with HF than in patients with non-HF. These results indicate that the cardioprotective effects of sodium-glucose cotransporter 2 inhibitors may, in part, be attributed to improved SNA.

Different contribution of sympathetic nerve activity to arterial velocity pulse index in hypertensive patients with and without diastolic dysfunction

Introduction

Left ventricular diastolic dysfunction (LVDD) is the main cause of heart failure with preserved ejection fraction (HFpEF). LVDD is related not only to arterial stiffness but also sympathetic nerve activity (SNA). Recent study demonstrated that increased muscle sympathetic nerve activity (MSNA) may be one of contributing factor for arterial stiffness. In clinical practice, Cardio-ankle vascular index (CAVI) provides a reproducible index of arterial stiffness, independent of blood pressure (BP). Recently, Arterial Velocity pulse Index (AVI), which is an index of arterial reflected waves, have been proposed as new index of arterial stiffness. We reported that AVI was associated with MSNA in hypertensive (HT) patients. However, it is still uncertain the effect of LVDD on the association between AVI and SNA in HT patients. Thus, we tested the hypothesis that AVI would be increased and related to MSNA in HT patients with LVDD.

Methods

Patients with essential HT subjects were included in this study. HT was diagnosed as systolic blood pressure (SBP) ≥140mmHg or diastolic blood pressure (DBP) ≥90mmHg. Patients with secondary HT was excluded. AVI was measured from left upper arm by NAS-1000 (Nihon Koden, Japan). CAVI was measured by VaSera VS-1500A (Fukuda Denshi, Japan). Transthoracic echocardiography was performed by trained sonographers. SNA was evaluated by direct recording of MSNA from peroneal nerves.

Results

25 HT patients were included (age 63±14 years, Male/Female 9/16). They were divided into two groups according to E/e' (no LVDD group, E/e' ≤9, N=12; LVDD group, E/e' &gt;9, N=13). There were no significant differences between no LVDD and LVDD groups in age (63±9 vs 69±9 years p=0.205), body mass index (23±3 vs 24±4 p=0.355), BP (SBP 139±16 vs 144±20mmHg p=0.524, DBP 87±15 vs 78±14mmHg p=0.167). LV Ejection Fraction (EF) and Stroke Volume (SV) did not differ between two groups (EF 66±7 vs 69±6% p=0.471, SV 58±7 vs 62±14ml p=0.599). MSNA had tendency to increase in LVDD group compared to no LVDD group (MSNA 53±10 vs 44±12 bursts/100 heartbeats, p=0.052). Contrary to our hypothesis, AVI and CAVI did not differ between two groups (AVI 27±7 vs 29±7 p=0.398, CAVI 8.7±1.4 vs 8.6±1.4 p=0.894). However, a significant correlation was seen between AVI and MSNA in no LVDD group (r=0.57, p&lt;0.05), but no correlation in LVDD group. There is no correlation between CAVI and MSNA in no LVDD and LVDD group. Significant relationship was observed between AVI and CAVI in LVDD group (r=0.61, p&lt;0.05), but no relationship in no LVDD group.

Conclusion

AVI was significantly associated with MSNA in HT patients without LVDD, but not with LVDD. CAVI was related to AVI in HT patients with LVDD, but not without LVDD. MSNA was slightly increased in HT patients with LVDD compared to without LVDD. These results indicate that augmented SNA could contribute to the increase in arterial stiffness in HT patients without LVDD, however, this contribution might be attenuated in HT patients with LVDD.

Funding Acknowledgement

Type of funding sources: None.

Effect of pulmonary vein isolation on left atrial remodeling and muscle sympathetic nerve activity in patients with atrial fibrillation

Background

Catheter ablation (CA) for atrial fibrillation (AF) improves left ventricular function and induces left atrium reverse remodeling (LARR). CA is also associated with the modulation of ganglionated plexi in the left atrium (LA), including stretch-sensitive sympathetic and parasympathetic nerve mechanoreceptors. Increased filling pressure and enlargement of LA stimulate stretch-sensitive sympathetic nerve mechanoreceptors in heart failure, which contribute augmented sympathetic nerve activity. However, little is known about an effect of CA on the interaction between the changes of LARR and sympathetic nerve activity.

Purpose

To test the hypothesis that CA induce the reduction in sympathetic nerve activity in accordance with LARR in patients with atrial fibrillation.

Methods

This study was conducted as a retrospective, observational study. Twenty-eight AF patients (65.4±12.1 years old) were included in this study. We measured mean blood pressure (BP), heart rate (HR), brain natriuretic peptide (BNP), and direct recording of muscle sympathetic nerve activity (MSNA) using microneurography technique before and 12 weeks after CA. Echocardiogram was also performed to assess LARR and left ventricular function. To evaluate the interaction between LARR and MSNA, AF patients were divided into two groups by presence (LARR group; n=18) and absence (no LARR group; n=10) of LARR according to left atrium volume index (LAVi) following CA.

Results

No significant differences were observed at baseline in BP, MSNA and LAVi between two groups. BP did not change significantly after CA in both groups. HR significantly increased in the LARR group (63.1±5.7 vs 69.9±7.8, p&lt;0.01) compared to no LARR group. CA significantly reduced MSNA in the LARR group (37.8±10.1 vs 24.9±8.8 bursts/min, p&lt;0.01), but there was no significant change in the no LARR group. The septal E/e' ratio (11.3±3.8 vs 9.8±2.9, p&lt;0.05), left ventricular end-systolic volume index (LVESVi) (24.4±11.9 vs 19.6±7.8 ml/m2, p&lt;0.05) and Ln BNP (4.0±1.2 vs 3.3±1.0 log/pg/ml, p&lt;0.05) were also significantly improved in the LARR group. On the other hand, in the no LARR group, there were no significancy in the changes of the septal E/e' ratio, LVESVi and Ln BNP. LVEF was not significantly changed in both two groups.

Conclusion

Our study shows CA reduced MSNA accompanied by LARR in AF patients. The reduction in MSNA, septal E/e' ratio, LVESVi and Ln BNP were all more pronounced in the LARR group compared to the no LARR group. These findings suggest that LARR is associated with the reduction in MSNA in AF patients, which was attributed to CA-induced modulation of stretch-sensitive sympathetic nerve mechanoreceptors.

Funding Acknowledgement

Type of funding sources: None.

Age differences in the association between arterial velocity pulse index and muscle sympathetic nerve activity in hypertensive patients

Background

Increased arterial stiffness characterize by aging. It is reported that age-related increases in muscle sympathetic nerve activity (MSNA) may be one of contributing factor for arterial stiffness. Arterial reflected wave was composed of SNA and aging. Increased arterial reflected wave partly plays an important role in blood pressure. Recently, we reported that arterial velocity pulse index (AVI), a novel index of arterial reflected waves, was associated with MSNA in hypertensive patients. It is still uncertain the effect of age on the association between AVI and SNA in hypertensive patients.

Method

Patients with essential HT and matched non-hypertensive control subjects were included in this study. HT was diagnosed as systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥90 mmHg. AVI was measured from left upper arm by NAS-1000. SNA was evaluated by direct recording of muscle sympathetic nerve activity (MSNA) from peroneal nerves.

Results

45 HT patients and 46 control subjects were included. Age, SBP and DBP were significantly increased in HT group compared to control (Age 63±14 vs 42±16 years, p&lt;0.001; SBP 144±16 vs 115±9 mmHg, p&lt;0.001; DBP 80±14 vs 67±9 mmHg, p&lt;0.001). MSNA and AVI were significantly increased in HT group compared to control (MSNA 34±10 vs 25±8 bursts/min, p&lt;0.05; AVI 28±9 vs 17±5, p&lt;0.05). AVI was significantly correlated with MSNA, age, and SBP in HT group. HT group was divided into two groups according to their age (group 1, age ≤63 N=21, group 2, age ≥64 N=26). AVI in group 1 showed correlation with MSNA (r=0.59, p&lt;0.05), but no correlation was seen in group 2. However excluded SBP&gt;160 mmHg subjects in group 2, significant correlation was clarified between AVI and MSNA (r=0.62, p&lt;0.05).

Conclusion

The relationship between AVI and MSNA in HT patients is preserved regardless of aging, however, high blood pressure over 160mmHg might obscure its correlation. These results indicate that AVI is useful to estimate sympathetic nerve activity in high aging HT patient treated &lt;160 blood pressure.

Funding Acknowledgement

Type of funding sources: None.

Differential contributions of choline phosphotransferases CPT1 and CEPT1 to the biosynthesis of choline phospholipid

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.

Gamma-Ray Observation of the Cygnus Region in the 100-TeV Energy Region

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

MIF Inhibition Suppresses Cell Viability and Induces Apoptosis via the ATF4-CHOP Pathway in Mouse Pituitary AtT-20 Cells

Cushing’s disease (CD) is characterized by cortisol overproduction due to ACTH hypersecretion from a pituitary tumour (PT). With an incidence of approximately 1.2 to 2.4 cases per million per year, CD patients have higher rates of morbidity and mortality than the general population. Surgical management is currently the first therapeutic option. However, remission rates vary between studies, and patients may suffer from complications caused by hormonal abnormalities from remnant PT tissues, the surgery itself, as medical treatment options are limited. Macrophage migratory inhibitory factor (MIF) is a cytokine expressed in various tumors, including ACTH-producing PTs, and has been found to play a crucial role in tumorigenesis. Previous studies demonstrate that MIF regulates cell growth via the signal transducer and activator of transcription 3 (STAT3) pathway, the mammalian target of rapamycin (mTOR) pathway, and autophagy. Together, these indicate MIF as a potential therapeutic target for PTs. However, the role of MIF in ACTH-producing PTs remains unknown. Using mouse ACTH-producing PT cells, AtT-20 cells as a model, we established that MIF overexpression led to increased cell growth. In contrast, pharmacological MIF inhibition by 4-iodo-6-phenylpyrimidine (4-IPP) and (S,R)-3-(4-Hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid (ISO-1) and genetic MIF downregulation by siRNA both suppressed cell viability and induced apoptosis, suggesting an anti-apoptotic role of MIF. Genetic MIF downregulation also increased the expression of apoptosis-inducible genes such as activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), and reduced ACTH production. However, pharmacological MIF inhibition had no effect on ACTH production, which suggests that the mechanism of pharmacological MIF inhibition may be different from MIF downregulation. Neither MIF upregulation nor downregulation affected cell signalling pathways such as the STAT3 pathway, the mTOR pathway, or autophagy. Our findings suggest that MIF inhibition can be a viable therapeutic approach for ACTH-producing PTs.

First Detection of sub-PeV Diffuse Gamma Rays from the Galactic Disk: Evidence for Ubiquitous Galactic Cosmic Rays beyond PeV Energies

We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.

Metabolic changes induced by TGF-β1 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-β1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-β1 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-β1. Knockdown of PISD alone without TGF-β1 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.

Novel index of arterial reflected waves, Arterial Velocity pulse Index, relates to muscle sympathetic nerve activity independent of Arterial Pressure volume Index in patients with hypertension

Background

Arterial reflected wave is determined by not only atherosclerosis but also sympathetic nerve activity. Recently, Arterial Velocity pulse Index (AVI), which is an index of arterial reflected waves, and Arterial Pressure volume Index (API), which is an index of volume of a conductive blood vessel, have been proposed as new index of arterial stiffness. However, it is unclear whether API and AVI would be associated with muscle sympathetic nerve activity (MSNA) in hypertensive subjects.

Purpose

The purpose of this study was to evaluate the correlation between AVI, API and MSNA in hypertensive subjects.

Method

41 hypertensive patients and 40 non-hypertensive subjects were included in this study. We performed a cross-sectional, observational study. Hypertension (HT) was defined as systolic blood pressure (SBP) ≥140 mmHg, diastolic blood pressure (DBP) ≥90 mmHg or medical treatment for HT. AVI and API was measured by NAS-1000 (Nihon Koden, Japan). MSNA, central sympathetic outflow to peripheral muscle, was recorded directly from peroneal nerve. MSNA was expressed by burst frequency (bursts/minute) and burst incidence (bursts/100heartbeats). Blood pressure, heart rate and MSNA were recorded simultaneously.

Results

Age, systolic and diastolic pressure were significantly higher in hypertensive patients compared to control (40±15 vs 61±13 years, p&lt;0.001; 142±16 vs 113±9 mmHg, p&lt;0.001; 81±14 vs 67±9 mmHg, p&lt;0.001). MSNA and AVI were significantly augmented in hypertensive patients compared to control (34±11 vs. 23±6 bursts/min, p&lt;0.05; 26±7 vs. 16±4, p&lt;0.05). AVI was correlated with MSNA in each group (hypertension: r=0.59, P&lt;0.001, non-hypertension: r=0.51, p&lt;0.001). However, no correlation was shown between API and MSNA in each group (hypertension: r=0.22, p=0.15, non-hypertension: r=0.07, p=0.63). Multiple regression analysis also showed MSNA was significantly related with AVI but was not with API.

Conclusion

Our finding showed that AVI relates to MSNA independent of API in patients with hypertension. It suggested that Novel index of arterial reflected waves, AVI, is helpful to estimate augmented SNA in hypertensive subjects regardless of volume of a conductive blood vessel.

Funding Acknowledgement

Type of funding source: None

The zonula occludens protein family regulates the hepatic barrier system in the murine liver

The hepatic barrier is indispensable for the physiological functions of the liver and is impaired under various pathological conditions. Tight junctions reportedly play a central role in hepatic barrier regulation; however, there is limited direct evidence supporting this observation, with few in vivo models or confirmations of the implicated molecular mechanisms presented to date. We inactivated the tight junction component gene, Tjp2/ZO-2, and the related molecule, Tjp1/ZO-1, in mouse livers. In humans, TJP2/ZO-2 mutations have been implicated in the development of human progressive familial intrahepatic cholestasis 4 (PFIC4). The mice deficient in either ZO-1 or ZO-2 in the liver did not exhibit major abnormalities. However, the ablation of both molecules impaired the molecular architecture as well as the structure and function of hepatocyte tight junctions, which disrupted the hepatic barrier and was lethal to the mice by 6 weeks of age. In mutant mice, bile canaliculus formation and cellular polarity were compromised; also, transporter expression and localization were deregulated. Moreover, typical hepatic zonation and bile duct formation were inhibited, and sinusoidal vessels were disorganized. These findings clarify the role of tight junctions and polarity in the hepatic barrier as well as the effect that their disruption has on liver tissue. The observations also suggest that liver-specific ZO-1^-/- and ZO-2^-/- mice could be used as models for PFIC4, and this will provide new insights into liver pathophysiology and clinical applications.

L-type amino acid transporter 1, LAT1, in growth hormone-producing pituitary tumor cells

Pituitary tumors (PTs) can cause significant mortality and morbidity due to limited therapeutic options. L-type amino acid transporters (LATs), in particular, the LAT1 isoform, is expressed in a variety of tumor cells. Pharmacological inhibition or genetic ablation of LAT1 can suppress leucine transport into cancer cells, resulting in suppression of cancer cell growth. However, roles of LAT1 in PTs have not been elucidated. Therefore, we assessed LAT1 expression in PTs and evaluated a LAT1-specific inhibitor, JPH203, on rat somatomammotroph tumor cells, GH4 cells. GH4 cells dominantly express LAT1 mRNA rather than other LAT isoforms, whereas LAT2 transcripts were most abundant in normal rat pituitary tissues. JPH203 inhibited leucine uptake and cell growth in GH4 cells in a concentration-dependent manner, and appeared to be independent of the mechanistic target, the rapamycin pathway. Although JPH203 did not induce apoptosis, it suppressed growth hormone production in GH4 cells. Also, genetic downregulation of LAT1 showed similar effects on cell growth and hormone production. These results indicated that restriction of LAT1 substrates by JPH203 modulated both cell growth and hormone production. In conclusion, LAT1 may be a new therapeutic target for PTs because its inhibition leads to suppression of cell growth as well as hormone production. JPH203 may represent a promising drug for clinical use in patients with PTs, with the potential of hormonal control and tumor suppression.

Different prognosis between severe and very severe obstructive sleep apnea patients; Five year outcomes

BACKGROUND

Obstructive sleep apnea (OSA) is characterized by augmented sympathetic nerve activity. In our previous study, patients with OSA and an apnea-hyperpnea index (AHI)>55events/h showed increased single-unit muscle sympathetic nerve activity compared to patients with OSA and AHI of 30-55events/h. However, the prognostic impact in these patients remains unclear.

METHODS

Ninety-one OSA patients were included. All patients who had indication for continuous positive airway pressure (CPAP) were treated with CPAP. Patients were divided into three groups: mild/moderate OSA (S), AHI<30events/h (n=44); severe OSA (SS), AHI 30-55events/h (n=29); and very severe OSA (VSS), AHI>55events/h (n=18). The primary endpoint was a composite outcome composed of death, cardiovascular events, stroke, and heart failure with hospitalization.

RESULTS

In the 5-year follow-up, the primary event rate in the SS group [3 events (7%)] was the same as that in the S group [3 events (10%)]. However, the VSS group showed a significantly higher primary event rate among the three groups [6 events (33%), p<0.05]. In Cox regression analysis, the VSS group had the highest hazard ratio compared to other risk factors.

CONCLUSIONS

CPAP was effective for preventing cardiovascular disease in patients with severe OSA, however patients with very severe OSA still had a high event rate, indicating that CPAP treatment might be insufficient to reduce the OSA-related risk burden in patients with very severe OSA. Additional systemic medical treatment for CPAP might be needed in patients with very severe OSA.

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.

Imaging of lysophosphatidylcholine in an induced pluripotent stem cell-derived endothelial cell network

Introduction

Vascular endothelial cell disorders are closely related to cardiovascular disease (CVD) and pulmonary diseases. Abnormal lipid metabolism in the endothelium leads to changes in cell signalling, and the expression of genes related to immunity and inflammation. It is therefore important to investigate the pathophysiology of vascular endothelial disorders in terms of lipid metabolism, using a disease model of endothelium.

Methods

Human induced pluripotent stem cell-derived endothelial cells (iECs) were cultured on a matrigel to form an iEC network. Lipids in the iEC network were investigated by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) imaging mass spectrometry (IMS) analysis. Ion fragments obtained by mass spectrometry were analysed using an infusion method, involving precursor ion scanning with fragment ion.

Results

The MALDI TOF IMS analysis revealed co-localized intensity of peaks at m/z 592.1 and 593.1 in the iEC network. Tandem mass spectrometry (MS/MS) analysis by MALDI-imaging, in conjunction with precursor ion scanning using an infusion method with lipid extracts, identified that these precursor ions were lysophosphatidylcholine (LPC) (22:5) and its isotype.

Conclusion

The MALDI-imaging analysis showed that LPC (22:5) was abundant in an iEC network. As an in vitro test model for disease and potential therapy, present analysis methods using MALDI-imaging combined with, for example, mesenchymal stem cells (MSC) to a disease derived iEC network may be useful in revealing the changes in the amount and distribution of lipids under various stimuli.

MON-713 Nuclear Corepressor; SMRT Acts as an Important Regulator for Both Beta-Oxidation and the Maturation of Myogenesis in Mouse C2C12 Cell

Background: Silencing Mediator of Retinoid and Thyroid hormone receptors (SMRT; NCoR2) is a transcriptional corepressor which has been recognized as an important player in the regulation of hepatic lipogenesis and the somatic development in mouse embryo. SMRT protein is also widely expressed in the mouse connective tissues, for example adipocyte and skeletal muscle, and we recently reported that the mouse of global deletion of SMRT causes significant obesity which is independent from thyroid hormone signaling and thermogenesis. However, the tissue specific role of SMRT in skeletal muscle is still unelucidated. Methods: To clarify this, we took the gene targeting strategy for SMRT using CRISPR Cas9, and made the myogenic C2C12 clone which lacks SMRT protein (C2C12-SMRTKO; SKO). For this study, wild type C2C12 cell (WT) and SKO cell were cultured in differentiation medium (DMEM+2% horse serum) for 5-6 days, and analyses for gene expression compared two cell types were performed. Results: We found the significant up-regulations of muscle specific beta-oxidation related genes (ex. Ppar delta, Ampk2), and higher protein level of PGC-1A in the SKO cell, suggesting that SKO cell had similar gene profile to that of rodent skeletal muscle in the exercise test. On the other hand, confocal microscopic analysis showed SKO cell had decreased cell-fusion and loss of myotube, indicating that the morphology was similar to immature mouse myoblasts. Further gene analyses compared between WT and SKO cell demonstrated that SKO cell had higher expressions of myogenic markers; MyoD and Myogenin. However, interestingly, the lower expressions of muscle constitutive genes; MHC, Actin, and Alpha-dystrobrevin were found in the SKO cell. These data indicate that the SKO cell has incomplete muscle fiber formation. Conclusion: Taken together, we demonstrate that SMRT works as a pivotal transcriptional mediator for both beta-oxidation and the process of myotube formation in C2C12 cell. Further inquiry for the cause of sarcopenia-like phenotype manifested in the SKO cell will be needed.

Renal iodine123-metaiodobenzylguanidine scintigraphy relates to muscle sympathetic nervous activity in heart failure with reduced ejection fraction

BACKGROUND

Renal denervation is effective for modulating augmented sympathetic nerve activity (SNA) in heart failure with reduced ejection fraction (HFrEF). We have demonstrated that renal iodine¹²³-metaiodobenzylguanidine (¹²³I-MIBG) scintigraphy is associated with muscle sympathetic nerve activity (MSNA) in patients with hypertension. However, it is unclear whether renal ¹²³I-MIBG scintigraphy is useful for assessment of SNA in HFrEF.

METHODS

The study population consisted of 24 HFrEF patients and 11 healthy subjects as controls. Patients with HFrEF underwent ¹²³I-MIBG scintigraphy and hemodynamics using a Swan-Ganz catheter (SGC). HFrEF was defined as echocardiography with left ventricular ejection fraction (LVEF) < 50%. MSNA was measured from the peroneal nerve for direct evaluation of SNA. Renal ¹²³I-MIBG scintigraphy was performed simultaneously with cardiac scintigraphy. The early and delayed kidney-to-mediastinum ratio (K/M), early and delayed heart-to-mediastinum ratio (H/M), and washout rate (WR) were calculated.

RESULTS

LVEFs were 35% ± 11% in patients with HFrEF and 63% ± 10% in the controls (p < 0.01). The WR of cardiac ¹²³I-MIBG showed no relation to MSNA, but was related to stroke volume (r = 0.45, p < 0.05). In contrast, the WR of renal ¹²³I-MIBG scintigraphy (average of both sides) showed a strong correlation with MSNA (BI, r = 0.70, p < 0.01; BF, r = 0.66, p < 0.01); however, no significant correlations were detected between renal ¹²³I-MIBG scintigraphy and SGC results.

CONCLUSIONS

The WR of renal ¹²³I-MIBG scintigraphy may reflect MSNA. Further studies are needed to clarify the relationship between renal ¹²³I-MIBG imaging and renal SNA.

The phosphatidylcholine transfer protein StarD7 is important for myogenic differentiation in mouse myoblast C2C12 cells and human primary skeletal myoblasts

StarD7 is a phosphatidylcholine (PC)-specific lipid transfer protein essential for the maintenance of mitochondrial PC composition, morphogenesis, and respiration. Here, we studied the role of StarD7 in skeletal myoblast differentiation using mouse myoblast C2C12 cells and human primary myoblasts. Immunofluorescence and immuno-electron microscopy revealed that StarD7 was distributed in the cytosol, inner mitochondria space, and outer leaflet of the outer mitochondrial membrane in C2C12 cells. Unlike human kidney embryonic cell line HEK293 cells, the mitochondrial proteinase PARL was not involved in the processing and maturation of StarD7 in C2C12 cells. StarD7 was constantly expressed during myogenic differentiation of C2C12 cells. The siRNA-mediated knockdown of StarD7 in C2C12 cells and human primary myoblasts significantly impaired myogenic differentiation and reduced the expression of myomaker, myomerger and PGC-1α. The reduction in mitochondrial PC levels and oxygen consumption rates, decreased expression of myomaker, myomerger and PGC-1α, as well as impaired myogenic differentiation, were completely restored when the protein was reintroduced into StarD7-knockout C2C12 cells. These results suggest that StarD7 is important for skeletal myogenesis in mammals.

Side-chain oxysterols suppress the transcription of CTP: Phosphoethanolamine cytidylyltransferase and 3-hydroxy-3-methylglutaryl-CoA reductase by inhibiting the interaction of p300 and NF-Y, and H3K27 acetylation

CTP: phosphoethanolamine cytidylyltransferase (Pcyt2) is the rate-limiting enzyme in mammalian phosphatidylethanolamine (PE) biosynthesis. Previously, we reported that increasedPcyt2 mRNA levels after serum starvation are suppressed by 25-hydroxycholesterol (HC) (25-HC), and that nuclear factor-Y (NF-Y) is involved in the inhibitory effects. Transcription of Hmgcr, which encodes 3-hydroxy-3-methylglutaryl-CoA reductase, is suppressed in the same manner. However, no typical sterol regulatory element (SRE) was detected in the Pcyt2 promoter. We were therefore interested in the effect of 25-HC on the modification of histones and thus treated cells with histone acetyltransferase inhibitor (anacardic acid) or histone deacetylase inhibitor (trichostatin A). The suppressive effect of 25-HC on Pcyt2 and Hmgcr mRNA transcription was ameliorated by trichostatin A. Anacardic acid, 25-HC and 24(S)-HC suppressed their transcription by inhibiting H3K27 acetylation in their promoters as evaluated by chromatin immunoprecipitation (ChIP) assays. 27-HC, 22(S)-HC and 22(R)-HC also suppressed their transcription, but 7α-HC, 7β-HC, the synthetic LXR agonist T0901317 and cholesterol did not. Furthermore, 25-HC inhibited p300 recruitment to the Pcyt2 and Hmgcr promoters, and suppressed H3K27 acetylation. 25-HC in the medium was easily conducted into cells. Based on these results, we concluded that 25-HC (and other side-chain oxysterols) in the medium was easily transferred into cells, suppressed H3K27 acetylation via p300 recruitment on the NF-Y complex in the Pcyt2 and Hmgcr promoters, and then suppressed transcription of these genes although LXR is not involved.

1417Effect of sodium glucose cotransporter 2 inhibitor on sympathetic nerve activity in type 2 diabetes mellitus patients

Background

Diabetes mellitus (DM) is a well-known risk factor for cardiovascular diseases. Augmented sympathetic nerve activity plays an important role in the progressive worsening disease severity. Most of anti-diabetic drugs were demonstrated to not only decrease blood glucose, but also increase sympathetic nerve activity. Recently, it has been reported that sodium glucose cotransporter 2 (SGLT2) inhibitor has beneficial effects on cardiovascular events in spite of the decrease in blood glucose in type 2 DM patients. The underlying mechanisms remain speculative; however, it is assumed that SGLT2 inhibitor would improve sympathetic nerve activity in type 2 DM patients.

Purpose

The purpose of this study was to evaluate the effect of SGLT2 inhibitor on sympathetic nerve activity in type 2 DM patients.

Methods

This study was designed as the prospective single-arm study. Type2 DM patients whose HbA1c >7.0% with at least one atherosclerotic risk factors (Hypertension, obesity, smoking history, aging ...) were included. Patients who had renal failure (eGFR<45ml/min/1.73m2) or high age patients (>80 years old) were excluded. We measured blood glucose, HbA1c and blood insulin concentration at baseline and 12 weeks after treatment of dapagliflozin (5mg/day). Muscle sympathetic nerve activity (MSNA) was applied to scrutinize accurate sympathetic nerve activity in type 2 DM patients. Also, baroreflex sensitivity was calculated by examining the relationship between MSNA and beat to beat diastolic blood pressure.

Results

Eleven type2 DM patients were included in this study. Body mass index, blood pressure, HbA1c and blood insulin concentration tended to decrease at 12weeks after dapagliflozin (body mass index: 27.2±6.3 vs. 24.9±3.2 kg/m2. systolic blood pressure: 121±12.3 vs. 118±13.6 mmHg. diastolic blood pressure: 74.3±6.3 vs. 72.5±7.6 mmHg. HbA1c: 7.6±0.3 vs. 7.2±0.7%. insulin: 9.7±7.2 vs. 8.8±5.1 μU/ml). Dapagliflozin significantly decrease MSNA and heart rate compared to baseline (46.7±7.5 vs. 38.6±6.9 bursts/minute, P<0.05. Heart rate: 80.6±8.5 vs. 72.8±7.4 beats per minute, P<0.05). However, there is no interaction between the reduction in MSNA and baroreflex sensitivity or insulin resistance.

12 weeks administration decreased MSNA

Conclusion

Our data demonstrated that dapagliflozin significantly decreased MSNA and HR beyond the lowering effect of blood glucose in type2 DM patients. These results indicate the favorable effect of SGLT2 inhibitor might be, in part, attributed to the improvement in sympathetic nerve activity.

First Detection of Photons with Energy beyond 100 TeV from an Astrophysical Source

We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100  TeV. As a result, we observed 24 photonlike events with E>100  TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100  TeV from an astrophysical source.

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.

Localization of Parotid Gland Tumors in Relation to the Intraparotid Facial Nerve on 3D Double-Echo Steady-State with Water Excitation Sequence

BACKGROUND AND PURPOSE

Reliable preoperative facial nerve mapping may help avoid or minimize facial nerve injury during parotid tumor resection. The purpose of this study was to investigate the diagnostic performance of the 3D double-echo steady-state with water excitation sequence in localizing parotid gland tumors through direct visualization of the intraparotid facial nerve in comparison with indirect methods of estimating the facial nerve location.

MATERIALS AND METHODS

We retrospectively reviewed 91 parotid gland tumors in 90 patients who underwent surgical resection and preoperative MR imaging, including the 3D double-echo steady-state with water excitation sequence. The tumor locations were categorized as deep or superficial on the basis of direct and 3 indirect methods: the facial nerve line, retromandibular vein, and Utrecht line. Surgical localization was considered the criterion standard. The diagnostic performance for localizing deep lobe lesions using direct and indirect methods was calculated and compared using the McNemar test.

RESULTS

Surgical localization confirmed 75 superficial lesions and 16 deep lesions. The interobserver variability of the 3D double-echo steady-state with water excitation sequence was excellent (κ = 0.870). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for localizing deep lobe lesions using the 3D double-echo steady-state with water excitation method were 97.8%, 87.5%, 100%, 100%, and 97.4%, respectively. These findings were significantly higher than the facial nerve line in sensitivity, the retromandibular vein in sensitivity, and the Utrecht line in accuracy and specificity (P < .05). Overall, the direct method was the most accurate, sensitive, and specific in localizing parotid gland tumors.

CONCLUSIONS

We can achieve higher diagnostic performance in localizing parotid gland tumors by directly visualizing the intraparotid facial nerve using the 3D double-echo steady-state with water excitation sequence compared with indirect methods.

A Phase II Study of Tailored-dose S-1 Plus Carboplatin Followed by Maintenance S-1 for Advanced Squamous Cell Lung Cancer: OSAKA-LCSG 1102

Objective A subset analysis of the LETS study suggested that S-1 plus carboplatin was more beneficial than paclitaxel plus carboplatin in terms of the overall survival (OS) in squamous cell lung cancer. However, the benefit of maintenance therapy for squamous cell non-small cell lung cancer (NSCLC) patients is still unknown. We herein report a phase II study to evaluate the efficacy and safety of a tailored dose of S-1 plus carboplatin followed by maintenance S-1 in chemotherapy-naive advanced squamous cell NSCLC. Methods Patients received carboplatin on day 1 plus S-1 on days 1 to 14 every 21 days. The dose of S-1 was determined by the body surface area and creatinine clearance. After four cycles of induction, non-progressive patients continued to receive S-1 until disease progression or unacceptable toxicity occurred. The primary endpoint was an objective response rate (RR) with a threshold value of 15%. The secondary endpoints were the progression-free survival (PFS) and OS from enrollment, the PFS in the maintenance phase, and safety. Results In the 33 patients analyzed, the rate of patients who met the primary endpoint was 30.3% (95% confidence interval: 15.6-48.7%), and the disease control rate was 75.8%. The median PFS and OS were 3.5 and 11.3 months, respectively. Ten patients received maintenance S-1, and the median PFS from the beginning of induction treatment was 5.3 months. Grade 3/4 toxicities with a frequency of more than 5% were all controllable. Conclusion Tailored-dose S-1 plus carboplatin followed by maintenance S-1 is an effective and feasible treatment for advanced squamous cell NSCLC.

The cosmic ray energy spectrum measured with the new Tibet hybrid experiment

We have upgraded the new Tibet ASgamma experiment in China since 2014 to measure the chemical composition of cosmic rays around the knee. This hybrid experiment consist of an air-shower-core detector array (YAC-II) to detect high energy electromagnetic component, the Tibet air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD). We have carried out a detailed air-shower Monte Carlo (MC) simulation to study the performance of the hybrid detectors by using CORSIKA (version 7.5000), which includes EPOS-LHC, QGSJETII-04, SIBYLL2.1 and SIBYLL2.3 hadronic interaction models. The preliminary results of the interaction model checking above 50 TeV energy region are reported in this paper, and the primary proton and helium spectra in the energy range 50 TeV to 1015 eV was derived from YAC-I data and is smoothly connected with direct observation data at lower energies and also with our previously reported works at higher energies within statistical errors. The knee of the (P+He) spectra is located around 400 TeV. The interaction model dependence in deriving the primary (P+He) spectra is found to be small (less than 25% in absolute intensity, 10% in position of the knee), and the composition model dependence is less than 10% in absolute intensity.

MON-470 Pharmacological Inhibition of LAT1 Suppresses Proliferation and Hormone Synthesis in Rat Pituitary Tumor GH4 Cells [cc1] Synthesis May Be Better as Only mRNAs Were Measured

Pituitary tumors (PTs) occur in almost 17 % of the population and they represent about 10 % of all intracranial tumors. Growth hormone-producing pituitary tumors account for about 12% of pituitary tumors. At present, many patients with this type of pituitary tumor suffer from symptoms and complications caused by abnormal hormone production and/or mass effects due to limited treatment options. L-type amino acid transporter 1 (LAT1/SLC7A5) delivers essential amino acids into cells, and higher expression of LAT1 has been detected in various types of cancer including gliomas and pancreatic cancers. Furthermore, several lines of evidence suggest that blockade of LAT1 in tumor cells suppresses mammalian target of rapamycin complex (mTORC) 1 activity, resulting in either cell growth arrest or apoptotic cell death. However, LAT1 expression has not been elucidated in normal pituitary glands or PTs. In addition, the effects of LAT1 inhibition on cell growth and hormone synthesis in PTs also remain unknown. Here we show that LAT1, with expression comparable to LAT2, LAT3 and LAT4 in the normal mouse pituitary gland, is predominantly expressed in rat pituitary tumor GH4 cells, which secrete GH and PRL. An LAT1-specific inhibitor, JPH203, provided by J-Pharma Co., Ltd., Yokohama Japan, suppressed growth of these cells as well as GH and PRL synthesis. Water-Soluble Tetrazolium salt (WST)-8 assay revealed that effective doses of JPH203 on cell proliferation were ranging from 5 to 40 μM. Analyzing Annexin V-Fluorescein isothiocyanate (FITC) binding by flow cytometry, we found that JPH203 (40μM) induced apoptosis within three days and growth arrest for at least three weeks in GH4 cells. JPH203 also reduced the amount of GH and PRL mRNAs 40 % and 50 %, respectively. These results indicate that LAT1 is a potential target of therapy for pituitary tumors. Next, the mechanisms of JPH203 action in GH4 cells were investigated. Unexpectedly, JPH203 did not have any apparent effects on the phosphorylation state of mTOR1 and its downstream effectors. In contrast, rapamycin decreased phosphorylation levels of these proteins, resulting in a reduction in cell proliferation. Our findings suggest that in pituitary tumor cells there could be differential amino acid sensing pathways, which regulate both cell growth and hormone synthesis. Further studies will be required to determine the mechanism of action of the LAT1 inhibitor in GH4 cells.

Test of the hadronic interaction models SIBYLL2.3, EPOS-LHC and QGSJETII- 04 with Tibet EAS core data

A hybrid experiment has been started by the ASγ experiment at Yangbajing (4300m a.s.l.) in Tibet since May 2009, that consists of a high-energy air-shower-core array (YAC-I) and a high-density air-shower array (Tibet-III). In this paper, we report our results to check the hadronic interaction models SIBYLL2.3, SIBYLL2.1, EPOS-LHC and QGSJETII-04 in the multi-tens TeV energy region using YAC-I+Tibet-III experimental data from May 2009 through January 2010. The effective live time is calculated as 106.05 days. The results show that the description of transverse momentum, inelastic cross-section and inelasticity for the 4 hadronic interaction models is consistent with YAC-I experimental data within 15% systematic errors range in the forward region below 100 TeV. Among them, the EPOS-LHC model is the best hadronic interaction model. Furthermore, we find that the H4a composition model is the best one below the 100 TeV energy region.

On the Solar Cycle Variation of the Solar Diurnal Anisotropy of Multi-TeV Cosmic-ray Intensity Observed with the Tibet Air Shower Array

We analyze the temporal variation of the solar diurnal anisotropy of the multi-TeV cosmic-ray intensity observed with the Tibet air shower array from 2000 to 2009, covering the maximum and minimum of the 23rd solar cycle. We comfirm that a remarkable additional anisotropy component is superposed on the Compton-Getting anisotropy at 4.0 TeV, while its amplitude decreases at higher energy regions. In constrast to the additional anisotropy reported by the Matsushiro experiment at 0.6 TeV, we find the residual component measured by Tibet at multi-TeV energies is consistent with being stable, with a fairly constant amplitude of 0.041% ± 0.003% and a phase at around 07.17 ± 00.16 local solar time at 4.0 TeV. This suggests the additional anisotropy observed by the Tibet experiment could result from mechanisms unrelated to solar activities.

Perioperative and prognostic implication of albumin-bilirubin-TNM score in Child-Pugh class A hepatocellular carcinoma

BACKGROUND AND AIM

A reliable classification for predicting postoperative prognosis and perioperative risk of hepatocellular carcinoma (HCC) patients is required to make a precise decision for HCC treatment. In the present study, we assessed the perioperative and prognostic importance of indocyanine green (ICG) testing, tumor-node-metastasis (TNM) stage, albumin-bilirubin (ALBI) grade, and ALBI-TNM (ALBI-T) score using consecutive resected HCC cases.

METHODS

Between 1998 and 2011, 273 consecutive patients who underwent primary and curative hepatectomy for HCC were identified. Among these 273 cases, 235 Child-Pugh class A patients were enrolled in the present study.

RESULTS

Correlation analysis showed that the value of linear predictor for ALBI grade was significantly correlated with ICG 15-minute retention rates (r = 0.51, P < 0.0001). Survival analysis for both recurrence-free survival (RFS) and overall survival (OS) showed there were significant differences between the two groups stratified by stage or ALBI-T score (stage, RFS: P = 0.01, OS: P = 0.003; ALBI-T, RFS: P < 0.0001, OS: P < 0.0001). In addition, Cox proportional hazard model identified ALBI-T score was a significant predictor for both RFS and OS (RFS, P = 0.001; OS, P = 0.004). Furthermore, ALBI-T score could predict perioperative risk in hepatectomy such as longer operation time and excessive intraoperative blood loss.

CONCLUSIONS

This study showed a robust association of ALBI-T score with postoperative HCC patient survival and perioperative risk in hepatectomy. ALBI-T score can be used as a simple and powerful tool for assessing HCC patients with further study.

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.

Synaptotagmin XIII expression and peritoneal metastasis in gastric cancer

BACKGROUND

Peritoneal metastasis is a frequent cause of death in patients with gastric cancer. The aim of this study was to identify molecules responsible for mediating peritoneal metastasis of gastric cancer.

METHODS

Transcriptome and bioinformatics analyses were conducted to identify molecules associated with peritoneal metastasis. The therapeutic effects of intraperitoneally administered small interfering (si) RNA were evaluated using mouse xenograft models. Expression of mRNA and protein was determined in gastric tissues from patients with gastric cancer.

RESULTS

Synaptotagmin XIII (SYT13) was expressed at significantly higher levels in patients with peritoneal recurrence, but not in those with hepatic or distant lymph node recurrence. Inhibition of SYT13 expression in a gastric cancer cell line transfected with SYT13-specific siRNA (siSYT13) was associated with decreased invasion and migration ability of the cells, but not with proliferation and apoptosis. Intraperitoneal administration of siSYT13 significantly inhibited the growth of peritoneal nodules and prolonged survival in mice. In an analysis of 200 patients with gastric cancer, SYT13 expression in primary gastric cancer tissues was significantly greater in patients with peritoneal recurrence or metastasis. A high level of SYT13 expression in primary gastric cancer tissues was an independent risk factor for peritoneal recurrence.

CONCLUSION

SYT13 expression in gastric cancer is associated with perioneal metatases and is a potential target for treatment.

Significance of Lysyl oxidase‑like 2 gene expression on the epithelial‑mesenchymal status of hepatocellular carcinoma

In the present study, we investigated the role of lysyl oxidase‑like 2 (LOXL2), the correlation between LOXL2 and epithelial to mesenchymal transition (EMT) and the effects of using β‑aminopropionitrile (BAPN) to inhibit LOXL2 with the aim of reducing tumor progression in hepatocellular carcinoma (HCC). The expression level of LOXL2 was evaluated in HCC and adjacent non‑cancerous tissues using quantitative reverse transcription polymerase chain reaction and clinicopathological analyses. The effects of BAPN on cell proliferation, migration and invasion were investigated in vitro. Additionally, LOXL2 expression was assessed in the culture supernatants of HCC cell lines. Our results revealed that LOXL2 expression was higher in HCC cell lines and tissues. There was a significant correlation between EMT status and LOXL2 levels (P=0.004). BAPN reduced migration and invasion in HCC cells. HCC patients with high levels of LOXL2 expression had relatively shorter disease‑free survival (P=0.009) and overall survival (P=0.035). The expression level of LOXL2 was similar between cell supernatants and HCC cell lines. A multivariate analysis demonstrated that portal vein invasion (P=0.015), venous invasion (P=0.026), serum AFP (α‑fetoprotein) levels (P=0.019) and LOXL2 expression (P=0.009) were independent prognostic factors. Our results indicated that a higher level of LOXL2 may contribute to tumor progression, indicating that LOXL2 has clinical value as a therapeutic target in HCC.

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.

Phase I study of chemoradiotherapy using gemcitabine plus nab-paclitaxel for unresectable locally advanced pancreatic cancer

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Background: Gemcitabine plus nab-paclitaxel (GnP) treatment is recommended for metastatic pancreatic adenocarcinoma (PDAC), and has been widely spread in our clinics. However, the usefulness for the patients with locally advanced PDAC is still controversial. We designed the phase I study to assess the toxicity and decide the recommended dose based on dose-limiting toxicity (DLT) of concurrent chemoradiotherapy using GnP for unresectable locally advanced (UR-LA) PDAC. Methods: UR-LA PDAC patients were enrolled in this clinical trial. The patients received the GnP on days 1, 8 and 15 every 28 days, and the cycles were repeated until PD. The patients were scheduled to receive gemcitabine (mg/m2) and nab-paclitaxel (mg/m2) at 5 dose levels: 400/75 (level 0), 600/75 (level 1), 600/100 (level 2), 800/100 (level 3) and 800/125 (level 4). Radiation therapy was delivered as a total dose of 50.4 Gy in 28 fractions, 1.8Gy per day. DLT was defined as grade 4 leucopenia or neutropenia ≥ 3 days, grade 3 neutropenia with fever ≥ 38℃, grade 3 or 4 thrombopenia, grade 3 non-hematological toxicity and > 14 days delay of treatment. Response and disease control rate, safety, adverse events, PFS and OS were evaluated. Results: Twelve patients were enrolled in this study. Treatment was well tolerated, and every 12 patients completed radiotherapy of 50.4 Gy. Our recommended dose was level 3, gemcitabine 800 mg/m2 and nab-paclitaxel 100 mg/m2. One patient experienced the DLT. The response rate was 41.7% and disease control rate was 75% (PR: 5, SD: 4, PD: 3). Median OS was 9.0 months. Among 12 patients, 6 (50%) patients underwent conversion surgery, and the pathological CR was observed in 2 patients. Conclusions: The concurrent chemoradiotherapy using GnP for UR-LA PDAC can be delivered safely and the high rate of conversion surgery was observed in our clinical trial. Based on this results, we will proceed the phase-II study. Clinical trial information: UMIN000020475.

Clinical implication of nutrition for neoadjuvant therapy and impact of nutritional support in pancreatic cancer

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Background: Several studies have shown that nutritional support is important to reduce chemotherapy-related toxicities and improve tolerance to chemotherapy, but little is known about the nutritional influence of neoadjuvant therapy (NAT) for pancreatic cancer. The aim of this study was to assess the influence of NAT on nutritional status and the effectiveness of postoperative nutritional support in patients with NAT for pancreatic cancer. Methods: Between 2010 and 2017, 169 consecutive patients who underwent pancreatoduodenectomy of pancreatic cancer were enrolled, and divided into the neoadjuvant group (NAG, n = 70) and the control group (CG, n = 99). We assessed the change of nutritional index (body weight, albumin and rapid turnover proteins; retinol binding protein, prealbumin and transferrin), inflammatory index, and inflammation-based prognostic scores during NAT. Perioperative change of rapid turnover proteins at the point of pre-operation, postoperative day (POD) 5, POD12 and POD21, and perioperative and oncological outcomes between NAG and CG were evaluated. Finally, we divided NAG into nutrition group (n = 27) who received postoperative enteral immunonutrition from POD 1 to POD 21 and without nutrition group (n = 41), and compared perioperative change of rapid turnover proteins between two groups. Results: After NAT, the retinol binding protein, prealbumin, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio and prognostic nutrition index significantly got worse in NAG (P < 0.05). The recovery of rapid turnover proteins after POD5 was significantly worse in NAG compared to CG (P < 0.05). There was no significant difference in the incidence of postoperative complications and time to adjuvant therapy between two groups. The recovery of retinol binding protein and prealbumin after POD12 was significantly better in nutrition group compared to without nutrition group (P < 0.05). Conclusions: NAT for pancreatic cancer could decrease nutritional status and its postoperative recovery. Postoperative enteral nutrition could be effective in patients with NAT for pancreatic cancer. Based on these results, we plan to perform the nutritional support at earlier stage of therapy.

Identification of a novel molecule target for the diagnosis, prediction, and treatment of hepatic metastasis of gastric cancer

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Background: Hepatic metastasis of gastric cancer has become a growing issue, because effective treatment and specific biomarkers are not available. The aim of this study was to identify a molecule mediating hepatic metastasis, which serves as a diagnostic marker, and to determine its potential as a therapeutic target. Methods: Stable knockdown gastric cancer cells were established using genome editing technique and cell activities were compared to control cells in vitro and in vivo. Tissue expression levels of the candidate molecule were evaluated in 300 patients with gastric cancer and correlated to clinicopathological parameters including patterns of metastasis and recurrences. Results: Global expression analysis revealed that synaptotagmin VII (SYT7) was overexpressed in gastric cancer tissues with hepatic metastasis. Gastric cancer cell lines differentially expressed high levels of SYT7 that positively correlated with those of SNAI1 and TGFB3, and inversely with RGS2. Stable knockout of SYT7 inhibited the proliferation of gastric cancer cells, indicated by increased apoptosis, and decreased cell migration, invasion, and adhesion abilities. The tumorigenicity of SYT7 knockout cells was moderately reduced in a mouse subcutaneous model and more strikingly decreased in a hepatic metastasis model. The protein expression levels of BCL2 and HIF1A were decreased in tumors formed by SYT7 knockout cells, and SYT7 levels in primary gastric cancer tissues were significantly associated with hepatic recurrence, metastasis, and adverse prognosis. Conclusions: SYT7 serves as a target for treating hepatic metastasis of gastric cancer as well as a diagnostic tool.

Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

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.

Metastatic pathway-specific transcriptome analysis identifies MFSD4 as a putative tumor suppressor and biomarker for hepatic metastasis in patients with gastric cancer

Gastric cancer (GC) with hepatic metastasis remains a fatal disease. Global expression profiling was conducted using tissues from patients who had GC with synchronous hepatic metastasis, and major facilitator superfamily domain containing 4 (MFSD4) was identified as a candidate biomarker for hepatic metastasis in GC. Functional and expression analyses of this molecule in GC cell lines and clinical samples were conducted. We analyzed MFSD4 expression, DNA methylation, and copy number. RNA interference experiments evaluated the effects of MFSD4 expression on cell phenotype and apoptosis. We analyzed tissues of 200 patients with GC to assess the diagnostic performance of MFSD4 levels for predicting hepatic recurrence, metastasis, or both. Differential expression of MFSD4 mRNA by GC cell lines correlated positively with the levels of NUDT13 and OCLN mRNAs and inversely with those of BMP2. Hypermethylation of the MFSD4 promoter was detected in cells with lower levels of MFSD4 mRNA. Inhibition of MFSD4 expression significantly increased the invasiveness and motility of GC cells but did not influence cell proliferation or apoptosis. MFSD4 mRNA levels in primary GC tissues were reduced in patients with concomitant hepatic metastasis or recurrence compared with those without. Low levels of MFSD4 mRNA in primary GC tissues were an independent risk factor of hepatic recurrence and metastasis. MFSD4 expression in gastric tissues may represent a useful biomarker for identification of patients at high risk for hepatic recurrence, metastasis, or both.

PAX5 gene as a novel methylation marker that predicts both clinical outcome and cisplatin sensitivity in esophageal squamous cell carcinoma

Therapeutic strategies for esophageal cancer largely depend on histopathological assessment. To select appropriate treatments of individual patients, we examined the background molecular characteristics of tumor malignancy and sensitivity to multidisciplinary therapy. Seventy-eight surgically-resected esophageal squamous cell carcinoma (ESCC) cases during 2001-2013 were examined. PAX5, a novel gene methylation marker in ESCC, was evaluated in the specimens, as methylation of this gene was identified as an extremely tumor-specific event in squamous cell carcinogenesis of head and neck. PAX5 methylation status was evaluated by quantitative MSP (QMSP) assays. Mean QMSP value was 15.7 (0-136.3) in ESCCs and 0.3 (0-8.6) in adjacent normal tissues (P < 0.001). The 78 cases were divided into high QMSP value (high QMSP, n = 26) and low QMSP value (low QMSP, n = 52). High QMSP cases were significantly associated with downregulated PAX5 expression (P = 0.040), and showed significantly poor recurrence-free survival [Hazard Ratio (HR) = 2.84; P = 0.005; 95% Confidence Interval (CI): 1.39-5.81] and overall survival (HR = 3.23; P = 0.002; 95%CI: 1.52-7.01) in multivariable analyses with histopathological factors. PAX5-knockdown cells exhibited significantly increased cell proliferation and cisplatin resistance. PAX5 gene methylation can predict poor survival outcomes and cisplatin sensitivity in ESCCs and could be a useful diagnostic tool for cancer therapy selection.