Prevention of vincristine-induced peripheral neuropathy by protecting the endothelial glycocalyx shedding.

Vincristine-induced peripheral neuropathy (VIPN) adversely affects the quality of life and treatment continuity of patients. The endothelial glycocalyx (eGCX) protects nerves from harmful substances released from the capillary vessels, but its role in peripheral neuropathy remains unclear. We investigated the impact of eGCX protection on VIPN. Using a murine model of VIPN, we administered nafamostat mesylate to protect the eGCX shedding, and analyzed the eGCX integrity and manifestation of peripheral neuropathy. Nafamostat treatment suppressed allodynia associated with neuropathy. Additionally, nafamostat administration resulted in the suppression of increased vascular permeability in capillaries of peripheral nerves, further indicating its positive influence on eGCX in VIPN model mice. This study provided the importance of eGCX in VIPN. With the potential for rapid clinical translation through drug repositioning, nafamostat may be a new promising treatment for the prevention of VIPN.

A class of chemical compounds enhances clustering of muscle nicotinic acetylcholine receptor in cultured myogenic cells.

Neuromuscular signal transmission is affected in various diseases including myasthenia gravis, congenital myasthenic syndromes, and sarcopenia. We used an ATF2-luciferase system to monitor the phosphorylation of MuSK in HEK293 cells introduced with MUSK and LRP4 cDNAs to find novel chemical compounds that enhanced agrin-mediated acetylcholine receptor (AChR) clustering. Four compounds with similar chemical structures carrying benzene rings and heterocyclic rings increased the luciferase activities 8- to 30-folds, and two of them showed continuously graded dose dependence. The effects were higher than that of disulfiram, a clinically available aldehyde dehydrogenase inhibitor, which we identified to be the most competent preapproved drug to enhance ATF2-luciferase activity in the same assay system. In C2C12 myotubes, all the compounds increased the area, intensity, length, and number of AChR clusters. Three of the four compounds increased the phosphorylation of MuSK, but not of Dok7, JNK. ERK, or p38. Monitoring cell toxicity using the neurite elongation of NSC34 neuronal cells as a surrogate marker showed that all the compounds had no effects on the neurite elongation up to 1 µM. Extensive docking simulation and binding structure prediction of the four compounds with all available human proteins using AutoDock Vina and DiffDock showed that the four compounds were unlikely to directly bind to MuSK or Dok7, and the exact target remained unknown. The identified compounds are expected to serve as a seed to develop a novel therapeutic agent to treat defective NMJ signal transmission.

Nafamostat mesylate decreases skin flap necrosis in a mouse model of type 2 diabetes by protecting the endothelial glycocalyx.

The success rate of flap tissue reconstruction has increased in recent years owing to advancements in microsurgical techniques. However, complications, such as necrosis, are still more prevalent in diabetic patients compared to non-diabetic individuals, presenting an ongoing challenge. To address this issue, many previous studies have examined vascular anastomoses dilation and stability, primarily concerning surgical techniques or drugs. In contrast, in the present study, we focused on microvascular damage of the peripheral microvessels in patients with diabetes mellitus and the preventative impact of nafamostat mesylate. Herein, we aimed to investigate the effects of hyperglycemia on glycocalyx (GCX) levels in mice with type 2 diabetes. We examined the endothelial GCX (eGCX) in skin flap tissue of 9-12-week-old type 2 diabetic mice (db/db mice) using a perforator skin flap and explored treatment with nafamostat mesylate. The growth rates were compared after 1 week. Heterotype (db/+) mice were used as the control group. Morphological examination of postoperative tissues was performed at 1, 3, 5, and 7 days post-surgery. In addition, db/db mice were treated with 30 mg/kg/day of nafamostat mesylate daily and were evaluated on postoperative day 7. Seven days after surgery, all db/db mice showed significant partial flap necrosis. Temporal observation of the skin flaps revealed a stasis-like discoloration and necrosis starting from the contralateral side of the remaining perforating branch. The control group did not exhibit flap necrosis, and the flap remained intact. In the quantitative assessment of endothelial glycans using lectins, intensity scoring showed that the eGCX in the db/db group was significantly thinner than that in the db/+ group. These results were consistent with the scanning electron microscopy findings. In contrast, treatment with nafamostat mesylate significantly improved the flap engraftment rate and suppressed eGCX injury. In conclusion, treatment with nafamostat mesylate improves the disrupted eGCX structure of skin flap tissue in db/db mice, potentially ameliorating the impaired capillary-to-venous return in the skin flap tissue.

Exploring the Vital Link Between Glioma, Neuron, and Neural Activity in the Context of Invasion.

Because of their ability to infiltrate normal brain tissue, gliomas frequently evade microscopic surgical excision. The histologic infiltrative property of human glioma has been previously characterized as Scherer secondary structures, of which the perivascular satellitosis is a prospective target for anti-angiogenic treatment in high-grade gliomas. However, the mechanisms underlying perineuronal satellitosis remain unclear, and therapy remains lacking. Our knowledge of the mechanism underlying Scherer secondary structures has improved over time. New techniques, such as laser capture microdissection and optogenetic stimulation, have advanced our understanding of glioma invasion mechanisms. Although laser capture microdissection is a useful tool for studying gliomas that infiltrate the normal brain microenvironment, optogenetics and mouse xenograft glioma models have been extensively used in studies demonstrating the unique role of synaptogenesis in glioma proliferation and identification of potential therapeutic targets. Moreover, a rare glioma cell line is established that, when transplanted in the mouse brain, can replicate and recapitulate the human diffuse invasion phenotype. This review discusses the primary molecular causes of glioma, its histopathology-based invasive mechanisms, and the importance of neuronal activity and interactions between glioma cells and neurons in the brain microenvironment. It also explores current methods and models of gliomas.

Prognostic value of radiological T category using conventional MRI in patients with oral tongue cancer: comparison with pathological T category.

PURPOSE: This study aimed to compare the radiological tumor (T)-category using multiparametric MRI with the pathological T category in patients with oral tongue squamous cell carcinoma (OTSCC) and to examine which is a better predictor of prognosis. METHODS: This retrospective study included 110 consecutive patients with surgically resected primary OTSCC who underwent preoperative contrast-enhanced MRI. T categories determined by maximum diameter and depth of invasion were retrospectively assessed based on the pathological specimen and multiparametric MRI. The MRI assessment included the axial and coronal T1-weighted image (T1WI), axial T2-weighted image (T2WI), coronal fat-suppressed T2WI, and axial and coronal fat-suppressed contrast-enhanced T1WI (CET1WI). Axial and coronal CET1WI measurements were divided into two groups: measurements excluding peritumoral enhancement (MEP) and measurements including peritumoral enhancement. The prognostic values for recurrence and disease-specific survival after radiological and pathological T categorization of cases into T1/T2 and T3/T4 groups were compared. RESULTS: The T category of MEP on coronal CET1WI was the most relevant prognostic factor for recurrence [hazard ratio (HR) = 3.30, p = 0.001] and the HR was higher than the HR for pathological assessment (HR = 2.26, p = 0.026). The T category determined by MEP on coronal CET1WI was also the most relevant prognostic factor for disease-specific survival (HR = 3.12, p = 0.03), and the HR was higher than the HR for pathological assessment (HR = 2.02, p = 0.20). CONCLUSION: The T category determined by MEP on the coronal CET1WI was the best prognostic factor among all radiological and pathological T category measurements.

Analysis of spinopelvic parameters in adult patients with lumbosacral transitional vertebrae.

PURPOSE: Spinopelvic sagittal alignment is crucial for assessing balance and determining treatment efficacy in patients with adult spinal deformity (ASD). Only a limited number of reports have addressed spinopelvic parameters and lumbosacral transitional vertebrae (LSTV). Our primary objective was to study spinopelvic sagittal parameter changes in patients with LSTV. A secondary objective was to investigate clinical symptoms and quality of life (QOL) in patients with LSTV. METHODS: In this study, we investigated 371 participants who had undergone medical check-ups for the spine. LSTV was evaluated using Castellvi's classification, and patients were divided into LSTV+ (type II-IV, L5 vertebra articulated or fused with the sacrum) and LSTV- groups. After propensity score matching for demographic data, we analyzed spinopelvic parameters, sacroiliac joint degeneration, clinical symptoms, and QOL for these two participant groups. Oswestry Disability Index (ODI) scores and EQ-5D (EuroQol 5 dimensions) indices were compared between the two groups. RESULTS: Forty-four patients each were analyzed in the LSTV + and LSTV- groups. The LSTV + group had significantly greater pelvic incidence (52.1 ± 11.2 vs. 47.8 ± 10.0 degrees, P = 0.031) and shorter pelvic thickness (10.2 ± 0.9 vs. 10.7 ± 0.8 cm, P = 0.018) compared to the LSTV- group. The "Sitting" domain of ODI (1.1 ± 0.9 vs. 0.6 ± 0.7, P = 0.011) and "Pain/Discomfort" domain of EQ-5D (2.0 ± 0.8 vs. 1.6 ± 0.7, P = 0.005) were larger in the LSTV + group. CONCLUSION: There was a robust association between LSTV and pelvic sagittal parameters. Clinical symptoms also differed between the two groups in some domains. Surgeons should be aware of the relationship between LSTV assessment, radiographic parameters and clinical symptoms.

An appropriate method for predicting the femoral angle on whole-body X-ray images from full-spine X-ray images.

INTRODUCTION: The importance of lower-limb compensation in patients with spinal malalignment due to spinal pathologies has been emphasized. The latest whole-body X-ray images (WBX) have enabled evaluations of whole-body alignment from head to toe. However, WBX is still not commonly available. Thus, the present study aimed to examine an alternative measurement method of the femoral angle on usual full-spine X-ray images (FSX) that approximates the femoral angle on WBX. METHODS: A total of 50 patients (age, 52.8 ± 25.3 years; female, n = 26; male, n = 24) underwent WBX and FSX. The following parameters were measured on lateral view X-rays: WBX and FSX femoral angle (angle between the femoral axis and a perpendicular line); FSX femoral distance (distance from the center of femoral head to the distal femur on FSX); WBX intersection length (length between the center of the femoral head and the intersection point [the point at which the line connecting the center of the femoral head and the midpoint of the femoral condyle intersects the center line of the femur] on WBX). RESULTS: The WBX femoral angle, and FSX femoral angle were 0.16 ± 4.2°, and -0.53 ± 4.1°, respectively. The FSX femoral distance was 102.7 ± 41.1 mm. An ROC curve analysis revealed that the cut-off value of the FSX femoral distance associated with minimal difference in the WBX and FSX femoral angles (<3°) was 73 mm (sensitivity 83.3%, specificity 87.5%, AUC 0.80). The WBX intersection length was 105.3 ± 27.3 mm. CONCLUSION: To calculate the femoral angle on FSX that approximates the WBX femoral angle, the femoral distance on FSX ≥73 mm is preferable. We suggest using the FSX femoral distance within the range of 80 mm-130 mm as a simple numerical value that meets all criteria.

Loss of the N-acetylgalactosamine side chain of the GPI-anchor impairs bone formation and brain functions and accelerates the prion disease pathology.

Glycosylphosphatidylinositol (GPI) is a posttranslational glycolipid modification of proteins that anchors proteins in lipid rafts on the cell surface. Although some GPI-anchored proteins (GPI-APs), including the prion protein PrPC, have a glycan side chain composed of N-acetylgalactosamine (GalNAc)-galactose-sialic acid on the core structure of GPI glycolipid, in vivo functions of this GPI-GalNAc side chain are largely unresolved. Here, we investigated the physiological and pathological roles of the GPI-GalNAc side chain in vivo by knocking out its initiation enzyme, PGAP4, in mice. We show that Pgap4 mRNA is highly expressed in the brain, particularly in neurons, and mass spectrometry analysis confirmed the loss of the GalNAc side chain in PrPC GPI in PGAP4-KO mouse brains. Furthermore, PGAP4-KO mice exhibited various phenotypes, including an elevated blood alkaline phosphatase level, impaired bone formation, decreased locomotor activity, and impaired memory, despite normal expression levels and lipid raft association of various GPI-APs. Thus, we conclude that the GPI-GalNAc side chain is required for in vivo functions of GPI-APs in mammals, especially in bone and the brain. Moreover, PGAP4-KO mice were more vulnerable to prion diseases and died earlier after intracerebral inoculation of the pathogenic prion strains than wildtype mice, highlighting the protective roles of the GalNAc side chain against prion diseases.

Decreased neutrophil counts prolong inflammation in acute pancreatitis and cause inflammation spillover to distant organs.

BACKGROUND/OBJECTIVE: Acute pancreatitis is an aseptic inflammation caused by pathologically activated pancreatic enzymes and inflammatory mediators produced secondarily by neutrophils and other inflammatory cells and is one of the most difficult diseases to treat. This study aimed to investigate the role of neutrophils in pancreatitis by examining tissue dynamics. METHODS: We created a model of caerulein-induced pancreatitis in 12-week-old male granulocyte colony-stimulating factor knockout mice (G-CSF-KO) and wild-type littermate control mice (six intraperitoneal injections of caerulein [80 µg/kg body weight] at hourly intervals for 2 days). Mice were sacrificed 0, 3, 6, 12, 24, 36, 48, 72, and 168 h after caerulein administration and examined histologically. RESULTS: The survival rate after one week of caerulein administration was 100 % in the control mice, whereas it was significantly lower (10 %) in the G-CSF-KO mice. Histological examination revealed significant hemorrhage and inflammatory cell migration in the G-CSF-KO mice, indicating prolonged inflammation. CONCLUSION: Prolonged inflammation was observed in the G-CSF-KO mice. Tissue cleanup by neutrophils during the acute phase of inflammation may influence healing through the chronic phase.

Autoimmune glial fibrillary acidic protein astrocytopathy associated with breast cancer: a case report.

BACKGROUND: Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy (GFAP-A) is an autoimmune inflammatory central nervous system disorder characterized by the detection of autoantibodies that recognize GFAP in CSF. The pathogenesis of GFAP-A is poorly understood. Some patients had a neoplasm detected and GFAP expressed by neoplasms is plausible as immunogen triggering paraneoplastic neurological autoimmunity. CASE PRESENTATION: We report a case of 76-year-old female patient with GFAP-A complicated with breast cancer. She presented with altered consciousness, nuchal rigidity, speech disturbances, and weakness. Her clinical symptoms were improved by immunotherapy and cancer treatments. Immunohistochemical analysis showed that the restricted tumor expressed GFAP. The infiltration of CD3 + T cells were observed in the peritumoral and intratumoral areas. The most common infiltrating lymphocytes were CD8 + T cells. CD4 + T cells and CD20 + B cells were also observed in the predominant peritumoral area. CONCLUSIONS: These results suggest that GFAP-A may occur in a paraneoplastic neurological syndrome associated with breast cancer.

Utility of ultrasonography in the diagnosis of lumbar spondylolysis in adolescent patients.

BACKGROUND: This study aims to investigate the utility of the Doppler effect on ultrasonography for the diagnosis of very early- and early-stage lumbar spondylolysis in adolescent patients. METHODS: In total, 76 adolescent patients with acute and subacute low back pain were prospectively enrolled, with 46 having lumbar spondylolysis and the remaining 30 having low back pain without spondylolysis. MRI and/or computed tomograms scans revealed very early- and early-stage lumbar spondylolysis. Furthermore, positive Doppler findings in ultrasonography around the area from the facet joint to the laminae were investigated. RESULTS: There were no significant differences in age (p > 0.99) and body mass index (p = 0.11) between cases with and without spondylolysis. Very early- and early-stage spondylolysis were observed in 27.6% and 72.4% of patients, respectively. Positive power Doppler was 91.3% and 33.3% in cases with and without spondylolysis, respectively, which was significantly higher in spondylolysis (p < 0.001). The sensitivity and specificity of this positive power Doppler were 91.4% and 66.7%, respectively. Furthermore, the rate of positive power Doppler was significantly higher in early-stage spondylolysis (p = 0.02), with 75.0% and 97.6% sensitivity in very early- and early-stage spondylolysis, respectively. CONCLUSIONS: A positive Doppler effect on ultrasonography is effective for screening very early- and early-stage spondylolysis in adolescent patients in an outpatient clinic.

Surgical outcomes in instrumented surgery for dumbbell type spinal cord tumor -the comparison with non-instrumented surgery for spinal cord tumor.

BACKGROUND: There is little information on outcomes for spinal cord tumor treated surgically with instrumentation. Analysis of surgical outcomes and complications in such cases is needed to develop generalizable conclusions and to help inform patients. METHODS: The subjects were 41 patients treated with instrumentation surgery for dumbbell type tumor resection. Demographic data; tumor histology, level, and location; number of fused vertebra; use of a bilateral or hemilateral screw; operative time; EBL; TcMEP monitoring; lumbar subarachnoid drainage; duration of subfascial drainage; postoperative motor and sensory deficits; CSF leakage, implant-related complications; time for union of fused vertebra; salvage surgeries, and pre-/postoperative McCormick scale were obtained from medical records. Significant factors related to postoperative motor deficits were identified. RESULTS: Postoperative motor deficit occurred in 9 cases (22.0%) and all recovered in 30 days after surgery. CSF leakage at 7 days and 2 years after surgery was subfascial (n = 31, n = 6) and subcutaneous (n = 3, n = 4). Cases with postoperative motor deficits more commonly had lower cervical lesions; those with CSF leakage had longer operative times; and those with delayed union had more use of hemilateral instrumentation. CONCLUSION: In this study in 41 spinal cord tumors treated surgically with instrumentation, the rate of postoperative motor deterioration was 22.0%, and CSF leakage was found in 17.1%.

Laterality of lumbar disc herniation.

BACKGROUND: Lumbar disc herniation (LDH) is most common in men aged 20-40 at the L4/5 level; however, left-right differences have not been reported. Improving our understanding of left- and right-side LDH may facilitate the estimation of mechanical load on intervertebral discs. Here, we assessed left-right differences in LDH via a retrospective analysis of LDH cases. METHODS: Among 10,972 surgical cases of LDH identified in the Nagoya Spine Group database, 2899 in which right- and left-LDH sides were observable in a single vertebral segment were identified (mean age 46.3 ± 16.6 years, 2028 males). The following characteristics of patients with right- and left-LDH were compared: age, LDH level, surgical technique, operative time, blood loss, length of hospital stay, preoperative Japan Orthopaedic Association (JOA) score, and JOA recovery rate. RESULTS: LDH occurred on the right and left sides in 1358 and 1541 patients, respectively, with patients with right-side LDH significantly older than those with left (47.9 ± 16.6 versus 45.0 ± 16.5, respectively; p < 0.001). No between-group differences in sex, age, LDH level, surgical technique, operative time, blood loss, length of hospital stay, preoperative JOA score, or JOA recovery rate were observed. The occurrence of right-side LDH increased with age, occurring in 42.7%, 45.1%, 49.9%, and 54.7% of patients aged 10-29, 30-49, 50-69, and 70-89 years, respectively. CONCLUSION: Left-side LDH was observed more frequently than right; however, right-side LDH incidence increased with age. No significant between-group differences regarding symptoms, treatments, or outcomes were observed.

Metabolic syndrome reduces spinal range of motion: The Yakumo study.

BACKGROUND: Excess visceral fat can accumulate owing to lack of exercise. The relationship between metabolic syndrome (MetS) and spinal range of motion (ROM) is not clear. The purpose of this study was to investigate the relationship between MetS and spinal alignment and ROM. METHODS: Orthopedic evaluation was prospectively performed in 544 participants. The participants were classified into two groups on the basis of the Japanese-specific MetS criteria proposed by the Japanese Committee of the Criteria for MetS (JCCMS). Lower back pain (LBP), knee joint pain with the visual analog scale (VAS), Kellgren-Lawrence (K-L) grade for knee osteoarthritis, body mass index (BMI), and spinal alignment and ROM were evaluated. RESULTS: Forty-four (8.1%) were diagnosed as having MetS. The prevalence rate of K-L grade 4 in the MetS group was significantly higher than that in the non-MetS group (p < 0.05). When sex, age, and BMI were evaluated as covariates, there were significant differences in the VAS score for knee pain (non-MetS group vs MetS group: 13.7 vs 23.3, p < 0.05), L1-S1 flexion spinal ROM (44.1° vs 38.1°, p < 0.001), flexion spinal inclination angle (SIA) ROM (107.6° vs 99.3°, p < 0.01), and SIA ROM (135.4° vs 124.0°, p < 0.05). CONCLUSIONS: Knee pain increased and flexion spinal ROM decreased significantly in the MetS group as compared with non-MetS group. Systemic factors associated with MetS may have a specific impact on spinal ROM while promoting knee osteoarthrosis and increased knee pain.

A Novel Mouse Model of Intrahepatic Cholangiocarcinoma Induced by Azoxymethane.

Cholangiocarcinoma is the second most common primary cancer of the liver and has a poor prognosis. Various animal models, including carcinogen-induced and genetically engineered rodent models, have been established to clarify the mechanisms underlying cholangiocarcinoma development. In the present study, we developed a novel mouse model of malignant lesions in the biliary ducts induced by the administration of the carcinogen azoxymethane to obese C57BLKS/J-db/db mice. A histopathological analysis revealed that the biliary tract lesions in the liver appeared to be an intrahepatic cholangiocarcinoma with higher tumor incidence, shorter experimental duration, and a markedly increased incidence in obese mice. Molecular markers analyzed using a microarray and a qPCR indicated that the cancerous lesions originated from the cholangiocytes and developed in the inflamed livers. These findings indicated that this is a novel mouse model of intrahepatic cholangiocarcinoma in the context of steatohepatitis. This model can be used to provide a better understanding of the pathogenic mechanisms of cholangiocarcinoma and to develop novel therapeutic strategies for this malignancy.

The phosphorylated retinoid X receptor-α promotes diethylnitrosamine-induced hepatocarcinogenesis in mice through the activation of ß-catenin signaling pathway.

Previous studies have shown that phosphorylation of the retinoid X receptor-α (RXRα) is associated with the development of hepatocellular carcinoma (HCC). However, these findings were revealed using HCC cell lines that express phosphorylated-RXRα (p-RXRα) proteins; therefore, it remains unclear whether p-RXRα affects hepatocarcinogenesis in vivo. Therefore, to investigate the biological function of p-RXRα in vivo, we developed a doxycycline-inducible ES cell line and transgenic mouse, both of which overexpress the phosphomimetic mutant form of RXRα, T82D/S260D, in a doxycycline-dependent manner. We found that the development of liver tumors, especially high-grade adenoma and HCC, was enhanced in diethylnitrosamine (DEN)-treated T82D/S260D-inducible mice. Moreover, the increased incidence of liver tumors in the transgenic mice was attributable to the promotion of cell cycle progression. Interestingly, the expression of ß-catenin protein and its target gene cyclin D1 was elevated in the liver tumors of DEN-treated T82D/S260D-inducible mice, concurrent with increased cytoplasmic and nuclear ß-catenin protein expression, indicating its stabilization and transcriptional activation. These results indicate that p-RXRα promotes DEN-induced hepatocarcinogenesis in mice through the activation of the ß-catenin signaling pathway, suggesting that p-RXRα may serve as a possible therapeutic target for HCC.

PD-1 Signaling Promotes Tumor-Infiltrating Myeloid-Derived Suppressor Cells and Gastric Tumorigenesis in Mice.

BACKGROUND & AIMS: Immune checkpoint inhibitors have limited efficacy in many tumors. We investigated mechanisms of tumor resistance to inhibitors of programmed cell death-1 (PDCD1, also called PD-1) in mice with gastric cancer, and the role of its ligand, PD-L1. METHODS: Gastrin-deficient mice were given N-methyl-N-nitrosourea (MNU) in drinking water along with Helicobacter felis to induce gastric tumor formation; we also performed studies with H/K-ATPase-hIL1B mice, which develop spontaneous gastric tumors at the antral-corpus junction and have parietal cells that constitutively secrete interleukin 1B. Mice were given injections of an antibody against PD-1 or an isotype control before tumors developed, or anti-PD-1 and 5-fluorouracil and oxaliplatin, or an antibody against lymphocyte antigen 6 complex locus G (also called Gr-1), which depletes myeloid-derived suppressor cells [MDSCs]), after tumors developed. We generated knock-in mice that express PD-L1 specifically in the gastric epithelium or myeloid lineage. RESULTS: When given to gastrin-deficient mice before tumors grew, anti-PD-1 significantly reduced tumor size and increased tumor infiltration by T cells. However, anti-PD-1 alone did not have significant effects on established tumors in these mice. Neither early nor late anti-PD-1 administration reduced tumor growth in the presence of MDSCs in H/K-ATPase-hIL-1ß mice. The combination of 5-fluorouracil and oxaliplatin reduced MDSCs, increased numbers of intra-tumor CD8+ T cells, and increased the response of tumors to anti-PD-1; however, this resulted in increased tumor expression of PD-L1. Expression of PD-L1 by tumor or immune cells increased gastric tumorigenesis in mice given MNU. Mice with gastric epithelial cells that expressed PD-L1 did not develop spontaneous tumors, but they developed more and larger tumors after administration of MNU and H felis, with accumulation of MDSCs. CONCLUSIONS: In mouse models of gastric cancer, 5-fluorouracil and oxaliplatin reduce numbers of MDSCs to increase the effects of anti-PD-1, which promotes tumor infiltration by CD8+ T cells. However, these chemotherapeutic agents also induce expression of PD-L1 by tumor cells. Expression of PD-L1 by gastric epithelial cells increases tumorigenesis in response to MNU and H felis, and accumulation of MDSCs, which promote tumor progression. The timing and site of PD-L1 expression is therefore important in gastric tumorigenesis and should be considered in design of therapeutic regimens.

Recombinant Antithrombin Attenuates Acute Respiratory Distress Syndrome in Experimental Endotoxemia.

Sepsis-induced endothelial acute respiratory distress syndrome is related to microvascular endothelial dysfunction caused by endothelial glycocalyx disruption. Recently, recombinant antithrombin (rAT) was reported to protect the endothelial glycocalyx from septic vasculitis; however, the underlying mechanism remains unknown. Here, we investigated the effect of rAT administration on vascular endothelial injury under endotoxemia. Lipopolysaccharide (LPS; 20 mg/kg) was injected intraperitoneally into 10-week-old male C57BL/6 mice, and saline or rAT was administered intraperitoneally at 3 and 24 hours after LPS administration. Subsequently, serum and/or pulmonary tissues were examined for inflammation and cell proliferation and differentiation by histologic, ultrastructural, and microarray analyses. The survival rate was significantly higher in rAT-treated mice than in control mice 48 hours after LPS injection (75% versus 20%; P < 0.05). Serum interleukin-1ß was increased but to a lesser extent in response to LPS injection in rAT-treated mice than in control mice. Lectin staining and ultrastructural studies showed a notable attenuation of injury to the endothelial glycocalyx after rAT treatment. Microarray analysis further showed an up-regulation of gene sets corresponding to DNA repair, such as genes involved in DNA helicase activity, regulation of telomere maintenance, DNA-dependent ATPase activity, and ciliary plasm, after rAT treatment. Thus, rAT treatment may promote DNA repair, attenuate inflammation, and promote ciliogenesis, thereby attenuating the acute respiratory distress syndrome caused by endothelial injury.

Potential therapeutic targets discovery by transcriptome analysis of an in vitro human gastric signet ring carcinoma model.

BACKGROUND: Loss of E-cadherin expression is frequently observed in signet ring carcinoma (SRCC). People with germline mutations in CDH1, which encodes E-cadherin, develop diffuse gastric cancer at a higher rate. Loss of E-cadherin expression is thus assumed to trigger oncogenic development. METHODS: To investigate novel therapeutic targets for gastric SRCC, we engineered an E-cadherin-deficient SRCC model in vitro using a human gastric organoid (hGO) with CDH1 knockout (KO). RESULTS: CDH1 KO hGO cells demonstrated distinctive morphological changes similar to SRCC and high cell motility. RNA-sequencing revealed up-regulation of matrix metalloproteinase (MMP) genes in CDH1 KO hGO cells compared to wild type. MMP inhibitors suppressed cell motility of CDH1 KO hGO cells and SRCC cell lines in vitro. Immunofluorescent analysis with 95 clinical gastric cancer tissues revealed that MMP-3 was specifically abundant in E-cadherin-aberrant SRCC. In addition, CXCR4 molecules translocated onto the cell membrane after CDH1 KO. Addition of CXCL12, a ligand of CXCR4, to the culture medium prolonged cell survival of CDH1 KO hGO cells and was abolished by the inhibitor, AMD3100. In clinical SRCC samples, CXCL12-secreting fibroblasts showed marked infiltration into the cancer area. CONCLUSIONS: E-cadherin deficient SRCCs might gain cell motility through upregulation of MMPs. CXCL12-positive cancer-associated fibroblasts could serve to maintain cancer-cell survival as a niche. MMPs and the CXCL12/CXCR4 axis represent promising candidates as novel therapeutic targets for E-cadherin-deficient SRCC.

Development of extrahepatic bile ducts and mechanisms of tumorigenesis: Lessons from mouse models.

The biliary system is a highly branched tubular network consisting of intrahepatic bile ducts (IHBDs) and extrahepatic bile ducts (EHBDs). IHBDs are derived from hepatic progenitor cells, while EHBDs originate directly from the endoderm through a separate branching morphogenetic process. Traits that are important for cancer are often found to overlap in developmental and other processes. Therefore, it has been suggested that intrahepatic cholangiocarcinomas (iCCAs) and extrahepatic cholangiocarcinomas (eCCAs) have different developmental mechanisms. While much evidence is being gathered on the mechanism of iCCAs, the evidence for eCCA is still very limited. The main reason for this is that there are very few appropriate animal models for eCCA. We can gain important insights from these animal models, particularly genetically engineered mouse models (GEMMs). GEMMs are immunocompetent and mimic human CCA subtypes with a specific mutational pattern, allowing the development of precancerous lesions, that is, biliary intraepithelial neoplasia (BilIN) and intraductal papillary neoplasm of the bile duct (IPNB). This review provides a summary of the pathogenesis and mechanisms of eCCA that can be revealed by GEMMs. Furthermore, we discuss several clinical questions, such as whether BilIN and IPNB really become malignant, whether the peribiliary gland is the origin of eCCAs, and others.