N,N-Dimethylformamide-stabilised palladium nanoparticles combined with bathophenanthroline as catalyst for transfer vinylation of alcohols from vinyl ether.

We report N,N-dimethylformamide-stabilised Pd nanoparticle (Pd NP)-catalysed transfer vinylation of alcohols from vinyl ether. Pd NPs combined with bathophenanthroline exhibited high catalytic activity. This reaction proceeded with low catalyst loading and the catalyst remained effective even after many rounds of recycling. The observation of the catalyst using transmission electron microscopy and dynamic light scattering implied no deleterious aggregation of Pd NPs.

Synthesis and Characterization of N,N-Dimethylformamide-Protected Palladium Nanoparticles and Their Use in the Suzuki-Miyaura Cross-Coupling Reaction.

Herein, the synthesis of new N,N-dimethylformamide (DMF)-protected palladium nanoparticles (Pd NPs-OAc) employing Pd (OAc)2 (= Pd(OCOCH3)2) as the NP precursor is reported. Pd NPs-OAc were comprehensively characterized by transmission electron microscopy, FT-IR, NMR, and X-ray photoelectron spectroscopy to determine the Pd NP size distribution and the coordination state of DMF. Pd NPs-OAc were compared with Pd NPs-Cl, using PdCl2 as the NP precursor. The Suzuki-Miyaura cross-coupling reaction proceeded efficiently in the presence of Pd NPs-OAc and a high catalytic activity was observed with a turnover number of up to 1.5 × 105. Furthermore, the Pd NP-OAc catalysts could be recycled at least five times.

EP4 receptor-associated protein regulates gluconeogenesis in the liver and is associated with hyperglycemia in diabetic mice.

Prostaglandin E2 receptor 4-associated protein (EPRAP) is a key molecule in suppressing inflammatory responses in macrophages. EPRAP is expressed not only in macrophages but also in hepatocytes; however, the role of EPRAP in hepatocytes has not yet been defined. To examine the physiological role of hepatic EPRAP in mice, we performed the glucose tolerance test and the hyperinsulinemic-euglycemic clamp in high-fat sucrose diet (HFSD)-fed wild-type (WT) and Eprap null mice. We evaluated the contribution of EPRAP to gluconeogenesis by pyruvate tolerance test and primary hepatocyte experiments. Furthermore, lentivirus-expressing Eprap-specific small-hairpin RNA was injected in db/ db mice. HFSD-fed Eprap null mice had significantly lower blood glucose levels than HFSD-fed WT mice. Eprap null mice also had low glucose levels after fasting or pyruvic acid injection. Moreover, primary hepatocytes from Eprap-deficient mice showed decreased glucose production and lower expression of the Phosphoenol pyruvate carboxykinase and Glucose 6-phosphatase genes. Lentivirus-mediated hepatic Eprap suppression decreased glucose levels and the expression of gluconeogenic genes in db/ db mice. We conclude that EPRAP regulates gluconeogenesis in hepatocytes and is associated with hyperglycemia in diabetic mice. Our data suggest that suppression of EPRAP could be a novel strategy for the treatment of diabetes.

Deficiency in EP4 Receptor-Associated Protein Ameliorates Abnormal Anxiety-Like Behavior and Brain Inflammation in a Mouse Model of Alzheimer Disease.

Microglia are thought to play key roles in the progression of Alzheimer disease (AD). Overactivated microglia produce proinflammatory cytokines, such as tumor necrosis factor-α, which appear to contribute to disease progression. Previously, we reported that prostaglandin E2 type 4 receptor-associated protein (EPRAP) promotes microglial activation. We crossed human amyloid precursor protein transgenic mice from strain J20+/- onto an EPRAP-deficient background to determine the role of EPRAP in AD. Behavioral tests were performed in 5-month-old male J20+/-EPRAP+/+ and J20+/-EPRAP-/- mice. EPRAP deficiency reversed the reduced anxiety of J20+/- mice but did not affect hyperactivity. No differences in spatial memory were observed between J20+/-EPRAP+/+ and J20+/-EPRAP-/- mice. In comparison with J20+/-EPRAP+/+, J20+/-EPRAP-/- mice exhibited less microglial accumulation and reductions in the Cd68 and tumor necrosis factor-α mRNAs in the prefrontal cortex and hippocampus. No significant differences were found between the two types of mice in the amount of amyloid-ß 40 or 42 in the cortex and hippocampus. J20+/-EPRAP-/- mice reversed the reduced anxiety-like behavior and had reduced microglial activation compared with J20+/-EPRAP+/+ mice. Further research is required to identify the role of EPRAP in AD, but our results indicate that EPRAP may be related to behavioral and psychological symptoms of dementia and inflammation in patients with AD.

EP4 Receptor-Associated Protein in Macrophages Protects against Bleomycin-Induced Pulmonary Inflammation in Mice.

Excessive activation of inflammatory macrophages drives the pathogenesis of many chronic diseases. EP4 receptor-associated protein (EPRAP) has been identified as a novel, anti-inflammatory molecule in macrophages. In this study, we investigated the role of EPRAP using a murine model of bleomycin (BLM)-induced pulmonary inflammation. When compared with wild-type mice, EPRAP-deficient mice exhibited significantly higher mortality, and increased accumulation of macrophages and proinflammatory molecules in the lung 7 d post-BLM administration. Accordingly, the levels of phosphorylated p105, MEK1/2, and ERK1/2 were elevated in EPRAP-deficient alveolar macrophages following BLM administration. In contrast, macrophage-specific EPRAP overexpression decreased the production of proinflammatory cytokines and chemokines, suggesting that EPRAP in macrophages plays a key role in attenuating BLM-induced pulmonary inflammation. As EPRAP is phosphorylated after translation, we examined the role of posttranslational modifications in cellular inflammatory activation using mouse embryo fibroblasts (MEFs) expressing mutant EPRAP proteins. Expression of mutant EPRAP, in which serine-108 and serine-608 were replaced with alanine (EPRAP S108A/S608A), markedly suppressed TNF-α production in LPS-treated MEFs. Conversely, the serine phosphatase 2A (PP2A) inhibitor, cantharidic acid, increased LPS-induced TNF-α production in MEFs expressing wild-type EPRAP, but not in MEFs expressing EPRAP S108A/S608A. Immunoprecipitation analyses demonstrated that EPRAP associated with PP2A in both MEFs and alveolar macrophages from BLM-treated mice. Our data suggest that PP2A dephosphorylates EPRAP, which may be a crucial step in exertion of its anti-inflammatory properties. For these reasons, we believe the EPRAP-PP2A axis in macrophages holds the key to treating chronic inflammatory disorders.

EP4 Receptor-Associated Protein in Microglia Promotes Inflammation in the Brain.

Microglial cells play a key role in neuronal damage in neurodegenerative disorders. Overactivated microglia induce detrimental neurotoxic effects through the excess production of proinflammatory cytokines. However, the mechanisms of microglial activation are poorly understood. We focused on prostaglandin E2 type 4 receptor-associated protein (EPRAP), which suppresses macrophage activation. We demonstrated that EPRAP exists in microglia in the brain. Furthermore, EPRAP-deficient mice displayed less microglial accumulation, and intraperitoneal administration of lipopolysaccharide (LPS) led to reduced expression of tumor necrosis factor-α and monocyte chemoattractant protein-1 mRNA in the brains of EPRAP-deficient mice. Consistently, EPRAP-deficient microglia showed a marked decrease in the production of tumor necrosis factor-α and monocyte chemoattractant protein-1 induced by LPS treatment compared with wild-type controls. In addition, EPRAP deficiency decreased microglial activation and neuronal cell death induced by intraventricular injection of kainic acid. EPRAP deficiency impaired the LPS-induced phosphorylation of c-jun N-terminal kinase and p38 mitogen-activated protein kinase in microglia. The phosphorylation levels of mitogen-activated protein kinase kinase 4-which phosphorylates c-jun N-terminal kinase and p38 mitogen-activated protein kinase-were also decreased in EPRAP-deficient microglia after LPS stimulation. Although EPRAP in macrophages plays a role in the attenuation of inflammation, EPRAP promotes proinflammatory activation of microglia through mitogen-activated protein kinase kinase 4-mediated signaling and may be key to the deteriorating neuronal damage brought on by brain inflammation.

EP4 Receptor-Associated Protein in Macrophages Ameliorates Colitis and Colitis-Associated Tumorigenesis.

Prostaglandin E2 plays important roles in the maintenance of colonic homeostasis. The recently identified prostaglandin E receptor (EP) 4-associated protein (EPRAP) is essential for an anti-inflammatory function of EP4 signaling in macrophages in vitro. To investigate the in vivo roles of EPRAP, we examined the effects of EPRAP on colitis and colitis-associated tumorigenesis. In mice, EPRAP deficiency exacerbated colitis induced by dextran sodium sulfate (DSS) treatment. Wild-type (WT) or EPRAP-deficient recipients transplanted with EPRAP-deficient bone marrow developed more severe DSS-induced colitis than WT or EPRAP-deficient recipients of WT bone marrow. In the context of colitis-associated tumorigenesis, both systemic EPRAP null mutation and EPRAP-deficiency in the bone marrow enhanced intestinal polyp formation induced by azoxymethane (AOM)/DSS treatment. Administration of an EP4-selective agonist, ONO-AE1-329, ameliorated DSS-induced colitis in WT, but not in EPRAP-deficient mice. EPRAP deficiency increased the levels of the phosphorylated forms of p105, MEK, and ERK, resulting in activation of stromal macrophages in DSS-induced colitis. Macrophages of DSS-treated EPRAP-deficient mice exhibited a marked increase in the expression of pro-inflammatory genes, relative to WT mice. By contrast, forced expression of EPRAP in macrophages ameliorated DSS-induced colitis and AOM/DSS-induced intestinal polyp formation. These data suggest that EPRAP in macrophages functions crucially in suppressing colonic inflammation. Consistently, EPRAP-positive macrophages were also accumulated in the colonic stroma of ulcerative colitis patients. Thus, EPRAP may be a potential therapeutic target for inflammatory bowel disease and associated intestinal tumorigenesis.

Hematogenous umbilical metastasis from colon cancer treated by palliative single-incision laparoscopic surgery.

Sister Mary Joseph's nodule (SMJN) is a rare umbilical nodule that develops secondary to metastatic cancer. Primary malignancies are located in the abdomen or pelvis. Patients with SMJN have a poor prognosis. An 83-year-old woman presented to our hospital with a 1-month history of a rapidly enlarging umbilical mass. Endoscopic findings revealed advanced transverse colon cancer. computer tomography and fluorodeoxyglucose-positron emission tomography revealed tumors of the transverse colon, umbilicus, right inguinal lymph nodes, and left lung. The feeding arteries and drainage veins for the SMJN were the inferior epigastric vessels. Imaging findings of the left lung tumor allowed for identification of the primary lung cancer, and a diagnosis of advanced transverse colon cancer with SMJN and primary lung cancer was made. The patient underwent local resection of the SMNJ and subsequent single-site laparoscopic surgery involving right hemicolectomy and paracolic lymph node dissection. Intra-abdominal dissemination to the mesocolon was confirmed during surgery. Histopathologically, the transverse colon cancer was confirmed to be moderately differentiated tubular adenocarcinoma. We suspect that SMJN may occur via a hematogenous pathway. Although chemotherapy for colon cancer and thoracoscopic surgery for the primary lung cancer were scheduled, the patient and her family desired home hospice. Seven months after surgery, she died of rapidly growing lung cancer.

Inhibitory role of Gas6 in intestinal tumorigenesis.

Growth arrest-specific gene (Gas) 6 is a γ-carboxyglutamic acid domain-containing protein, which shares 43% amino acid identity with protein S. Gas6 has been shown to enhance cancer cell proliferation in vitro. On the other hand, recent studies have demonstrated that Gas6 inhibits toll-like receptor-mediated immune reactions. Immune reactions are known to affect intestinal tumorigenesis. In this study, we investigated how Gas6 contributes to tumorigenesis in the intestine. Administration of recombinant Gas6 weakly, but significantly, enhanced proliferation of intestinal cancer cells (SW480 and HT29), whereas it suppressed the inflammatory responses of Lipopolysaccharide (LPS)-stimulated monocytes (THP-1). Compared with Gas6(+/+) mice, Gas6(-/-) mice exhibited enhanced azoxymethane/dextran sulfate sodium (DSS)-induced tumorigenesis and had a shorter survival. Gas6(-/-) mice also exhibited more severe DSS-induced colitis. DSS-treated Gas6(-/-) mice showed attenuated Socs1/3 messenger RNA expression and enhanced nuclear factor-kappaB activation in the colonic stroma, suggesting that the target of Gas6 is stromal cells. Bone marrow transplantation experiments indicated that both epithelial cells and bone marrow-derived cells are Gas6 sources. Furthermore, the number of intestinal tumors in Apc(Min) Gas6(-/-) mice was higher than that in Apc(Min) Gas6(+/+) mice, resulting in shorter survival. In a group of 62 patients with advanced colorectal cancer, Gas6 immunoreactivity in cancer tissues was positively correlated with prognosis. Thus, we revealed a unique in vivo inhibitory role of Gas6 during the progression of intestinal tumors associated with suppression of stromal immune reactions. These results suggest a novel therapeutic approach for colorectal cancer patients by regulation of stromal immune responses.

Nardilysin and ADAM proteases promote gastric cancer cell growth by activating intrinsic cytokine signalling via enhanced ectodomain shedding of TNF-α.

Nardilysin (NRDc), a metalloendopeptidase of the M16 family, promotes ectodomain shedding of the precursor forms of various growth factors and cytokines by enhancing the protease activities of ADAM proteins. Here, we show the growth-promoting role of NRDc in gastric cancer cells. Analyses of clinical samples demonstrated that NRDc protein expression was frequently elevated both in the serum and cancer epithelium of gastric cancer patients. After NRDc knockdown, tumour cell growth was suppressed both in vitro and in xenograft experiments. In gastric cancer cells, NRDc promotes shedding of pro-tumour necrosis factor-alpha (pro-TNF-α), which stimulates expression of NF-κB-regulated multiple cytokines such as interleukin (IL)-6. In turn, IL-6 activates STAT3, leading to transcriptional upregulation of downstream growth-related genes. Gene silencing of ADAM17 or ADAM10, representative ADAM proteases, phenocopied the changes in cytokine expression and cell growth induced by NRDc knockdown. Our results demonstrate that gastric cancer cell growth is maintained by autonomous TNF-α-NF-κB and IL-6-STAT3 signalling, and that NRDc and ADAM proteases turn on these signalling cascades by stimulating ectodomain shedding of TNF-α.

COX-2 inhibition alters the phenotype of tumor-associated macrophages from M2 to M1 in ApcMin/+ mouse polyps.

Macrophages are a major component of tumor stroma. Tumor-associated macrophages (TAMs) show anti- (M1) or protumor (M2) functions depending on the cytokine milieu of the tumor microenvironment. Cyclooxygenase-2 (COX-2) is constitutively expressed in a variety of tumors including colorectal cancer. TAMs are known to be a major source of COX-2 in human and mice intestinal tumors. COX-2 inhibitor reduces the number and size of intestinal adenomas in familial adenomatous polyposis patients and Apc(Min/+) mice. Although COX-2 inhibitor is thought to regulate cancer-related inflammation, its effect on TAM phenotype remains unknown. Here, we examined the effects of COX-2 inhibition on TAM phenotype and cytokine expression both in vivo and in vitro. Firstly, the selective COX-2 inhibitor celecoxib changed the TAM phenotype from M2 to M1, in proportion to the reduction in number of Apc(Min/+) mouse polyps. Concomitantly, the expression of M1-related cytokine interfron (IFN)-γ was significantly upregulated by celecoxib, although the M2-related cytokines interleukin (IL)-4, IL-13 and IL-10 were not significantly altered. Secondly, IFN-γ treatment attenuated M2 phenotype of mouse peritoneal macrophages and oriented them to M1 even in the presence of M2-polarizing cytokines such as IL-4, IL-13 and IL-10. Thus, our results suggest that COX-2 inhibition alters TAM phenotype in an IFN-γ-dependent manner and subsequently may reduce intestinal tumor progression.

[A case of primary liver carcinoma of intermediate (hepatocyte-cholangiocyte) phenotype: comparison of hemodynamics and histopathology].

A 58-year-old man was followed up for HBV-associated chronic hepatitis. A low echoic hepatic nodule 1.6cm in diameter developed in segment 8 of the liver. The tumor was hypervascular and showed enhancement on CV during hepatic arteriography (CTHA) and a defect on CT during arterial portography (CTAP). Strong enhancement, which lasted for 30 seconds, was observed at the margin of the tumor on single-level dynamic CTHA. The resected tumor was whitish, had no capsule, and consisted mainly of intermediate immature cells together with HCC-like and CCC-like tumor cells. These findings led to the diagnosis of primary liver carcinoma of intermediate (hepatocyte-cholangiocyte) phenotype. Cytokeratin (CK) 7, CK8, CK19, EMA and vimentin were positive and HP-1 and c-kit tests were negative on immunohistochemical staining. Staining with CD34+alphaSMA showed more muscular arterial vessels and sinusoid-like vessels in the peripheral zone of the tumor than in the central zone. Six months after the resection of the tumor, swollen abdominal lymph nodes were observed on US and CT, which aspiration needle biopsy showed to be metastasis of a hepatic tumor.

[Seven cases of gemcitabine-induced lung injury during treatment for pancreatic or biliary tract cancers].

Gemcitabine is an anti-cancer drug known to be safe and effective for pancreatic or biliary tract cancers, but lung injury is also known to be a rare side effect that sometimes becomes severe. Here we report seven cases of lung injury during gemcitabine treatment. Drug-induced lung injury was suspected in all cases. The male: female ratio was 5:2, and the average patient age was 71. Four had pancreatic cancers and three had biliary tract cancers. Gemcitabine had been administered an average 5.9 times at a dose of 1,141 mg. Patients showed a diffuse or patchy shadow mainly in the lower lung on computed tomography examination. Grades of adverse events were greater than 3 in all cases. Three patients died of the lung injury. Five cases had pulmonary emphysema, 2 had metastatic lung tumor as underlying pulmonary lesions, and these were assumed to have been important risk factors for drug-induced interstitial lung injury during gemcitabine treatment.

[A case of focal nodular hyperplasia presenting corona enhancement on single-level dynamic CT during hepatic arteriography].

A hepatic nodule was detected in segment 5/6 on abdominal US study in a 28 year-old male. The nodule was 7cm in diameter and the early phase of contrasted US, CT and MRI images showed spoke-wheel like vessels radiating from the center. No defect images were observed on postvascular phase contrasted US and SPIO MRI, which indicated the presence of Kupffer cells in the nodule. The nodule was diagnosed as a focal nodular hyperplasia (FNH) based on histological findings. The late phase of single level dynamic CT during hepatic arteriography (CTHA) showed corona enhancement of the nodule, which is considered to be characteristic of hypervascular metastatic liver tumors, hyperplastic nodules and HCCs. In our case, the drainage flow from the nodule may have been visualized as corona enhancement via the pathway from the sinusoid in the nodular periphery to the one in the adjacent and contiguous parenchyma.