GREB1 isoform 4 is specifically transcribed by MITF and required for melanoma proliferation.

Growth regulation by estrogen in breast cancer 1 (GREB1) is involved in hormone-dependent and -independent tumor development (e.g., hepatoblastoma). In this study, we found that a GREB1 splicing variant, isoform 4 (Is4), which encodes C-terminal half of full-length GREB1, is specifically expressed via microphthalmia-associated transcription factor (MITF) in melanocytic melanoma, and that two MITF-binding E-box CANNTG motifs at the 5'-upstream region of GREB1 exon 19 are necessary for GREB1 Is4 transcription. MITF and GREB1 Is4 were strongly co-expressed in approximately 20% of the melanoma specimens evaluated (17/89 cases) and their expression was associated with tumor thickness. GREB1 Is4 silencing reduced melanoma cell proliferation in association with altered expression of cell proliferation-related genes in vitro. In addition, GREB1 Is4 targeting by antisense oligonucleotide (ASO) decreased melanoma xenograft tumor formation and GREB1 Is4 expression in a BRAFV600E; PTENflox melanoma mouse model promoted melanoma formation, demonstrating the crucial role of GREB1 Is4 for melanoma proliferation in vivo. GREB1 Is4 bound to CAD, the rate-limiting enzyme of pyrimidine metabolism, and metabolic flux analysis revealed that GREBI Is4 is necessary for pyrimidine synthesis. These results suggest that MITF-dependent GREB1 Is4 expression leads to melanoma proliferation and GREB1 Is4 represents a new molecular target in melanoma.

Mitotic perturbation is a key mechanism of action of decitabine in myeloid tumor treatment.

Decitabine (DAC) is clinically used to treat myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Our genome-wide CRISPR-dCas9 activation screen using MDS-derived AML cells indicates that mitotic regulation is critical for DAC resistance. DAC strongly induces abnormal mitosis (abscission failure or tripolar mitosis) in human myeloid tumors at clinical concentrations, especially in those with TP53 mutations or antecedent hematological disorders. This DAC-induced mitotic disruption and apoptosis are significantly attenuated in DNMT1-depleted cells. In contrast, overexpression of Dnmt1, but not the catalytically inactive mutant, enhances DAC-induced mitotic defects in myeloid tumors. We also demonstrate that DAC-induced mitotic disruption is enhanced by pharmacological inhibition of the ATR-CLSPN-CHK1 pathway. These data challenge the current assumption that DAC inhibits leukemogenesis through DNMT1 inhibition and subsequent DNA hypomethylation and highlight the potent activity of DAC to disrupt mitosis through aberrant DNMT1-DNA covalent bonds.

Use of a gum elastic bougie in a cat with severe upper airway stenosis.

Background: Gum elastic bougie (GEB) is an airway management device for patients who are difficult to intubate and its use has been reported in human medicine. However, to our knowledge, no reports in veterinary medicine have described oxygenation using GEB. We describe a case in which GEB was used to maintain oxygenation in a cat with severe upper airway stenosis. Case Description: A 10-year-old neutered male domestic shorthair cat was diagnosed with a laryngeal tumor with severe upper airway stenosis. During anesthesia induction, the normal laryngeal structure could not be confirmed; orotracheal intubation was difficult, resulting in a "cannot intubate, cannot oxygenate" status. The GEB was inserted, making it possible to oxygenate the cat until a permanent tracheostoma could be created, but hypoventilation was noted. Conclusion: Although GEB are not useful for proper ventilation, they can be useful for temporary oxygenation in veterinary medicine when airway management is difficult.

Relationship between [18F]FDG PET/CT and metabolomics in patients with colorectal cancer.

INTRODUCTION: Advances in metabolomics have significantly improved cancer detection, diagnosis, treatment, and prognosis. OBJECTIVES: To investigate the relationship between metabolic tumor volume (MTV) using 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET)/ computed tomography (CT) and metabolomics data in patients with colorectal cancer (CRC). METHODS: The metabolome in tumor tissues was analyzed using capillary electrophoresis time-of-flight mass spectrometry in 33 patients with newly diagnosed CRC who underwent FDG PET/CT before treatment and had tumor tissue post-surgery. Based on the FDG PET data, MTV was calculated and was dichotomized according to the median value, and tumors were divided into low-MTV and high-MTV tumors. Metabolomics data were compared between the low-MTV and high-MTV tumors. RESULTS: The levels of most glycolysis-related metabolites were not different between low-MTV and high-MTV tumors. The level of component of the initial part of the tricarboxylic acid (TCA) cycle, citrate, was significantly lower in the high-MTV tumor than in the low-MTV tumor. The TCA intermediate succinate level was significantly higher in the high-MTV tumor than in the low-MTV tumor. In contrast, the TCA intermediate fumarate level was significantly lower in the high-MTV tumor than in the low-MTV tumor. The levels of many amino acids were significantly higher in the high-MTV tumor than in the low-MTV tumor. CONCLUSIONS: Although preliminary, these results suggest that tumors with high FDG metabolism in CRC may obtain more energy by using a reverse reaction of the TCA cycle and amino-acid metabolism. However, further research is required to clarify this relationship.

MEK inhibition preferentially suppresses anchorage-independent growth in osteosarcoma cells and decreases tumors in vivo.

Osteosarcoma is the most common high-grade malignancy of bone, and novel therapeutic options are urgently required. Previously, we developed mouse osteosarcoma AXT cells that can proliferate both under adherent and nonadherent conditions. Based on metabolite levels, nonadherent conditions were more similar to the in vivo environment than adherent conditions. A drug screen identified MEK inhibitors, including trametinib, that preferentially decreased the viability of nonadherent AXT cells. Trametinib inhibited the cell cycle and induced apoptosis in AXT cells, and both effects were stronger under nonadherent conditions. Trametinib also potently decreased viability in U2OS cells, but its effects were less prominent in MG63 or Saos2 cells. By contrast, MG63 and Saos2 cells were more sensitive to PI3K inhibition than AXT or U2OS cells. Notably, the combination of MAPK/ERK kinase (MEK) and PI3K inhibition synergistically decreased viability in U2OS and AXT cells, but this effect was less pronounced in MG63 or Saos2 cells. Therefore, signal dependence for cell survival and crosstalk between MEK-ERK and PI3K-AKT pathways in osteosarcoma are cell context-dependent. The activation status of other kinases including CREB varied in a cell context-dependent manner, which might determine the response to MEK inhibition. A single dose of trametinib was sufficient to decrease the size of the primary tumor and circulating tumor cells in vivo. Moreover, combined administration of trametinib and rapamycin or conventional anticancer drugs further increased antitumor activity. Thus, given optimal biomarkers for predicting its effects, trametinib holds therapeutic potential for the treatment of osteosarcoma.

Phosphoethanolamine Accumulation Protects Cancer Cells under Glutamine Starvation through Downregulation of PCYT2.

Tolerance to severe tumor microenvironments, including hypoxia and nutrient starvation, is a common feature of aggressive cancer cells and can be targeted. However, metabolic alterations that support cancer cells upon nutrient starvation are not well understood. Here, by comprehensive metabolome analyses, we show that glutamine deprivation leads to phosphoethanolamine (PEtn) accumulation in cancer cells via the downregulation of PEtn cytidylyltransferase (PCYT2), a rate-limiting enzyme of phosphatidylethanolamine biosynthesis. PEtn accumulation correlated with tumor growth under nutrient starvation. PCYT2 suppression was partially mediated by downregulation of the transcription factor ELF3. Furthermore, PCYT2 overexpression reduced PEtn levels and tumor growth. In addition, PEtn accumulation and PCYT2 downregulation in human breast tumors correlated with poor prognosis. Thus, we show that glutamine deprivation leads to tumor progression by regulating PE biosynthesis via the ELF3-PCYT2 axis. Furthermore, manipulating glutamine-responsive genes could be a therapeutic approach to limit cancer progression.

Psychometric profile of the Ages and Stages Questionnaires, Japanese translation.

BACKGROUND: This study assessed the psychometric profile of 10 questionnaires (every 6 months, from 6 to 60 months) from the Japanese translation of the Ages and Stages Questionnaires, third edition (J-ASQ-3). METHODS: Data from 439 children in a birth cohort were used to identify the J-ASQ-3 score distribution, establish cut-off scores, and calculate the instrument's internal consistency. Data were also collected from 491 outpatients to examine J-ASQ-3 test-retest reliability and concurrent validity, which was examined using the Kyoto Scale of Psychological Development (KSPD) and the Japanese version of the Denver Developmental Screening Test II (J-Denver II). Both the original and the alternative screening criteria of the ASQ-3 were used (failure in at least one and at least two domains, respectively). RESULTS: Cronbach's alpha for each J-ASQ-3 subscale on each questionnaire ranged from 0.45 to 0.89. Test-retest reliability was >0.75 for the subscales on almost all questionnaires. Concurrent validity was also adequate. In comparison with the screening results of the KSPD, the overall sensitivity and specificity were 96.0% and 48.8%, respectively, when the ASQ-3 original criterion was used, and 92.1% and 74.9%, respectively, when the alternative criterion was used. In comparison with the screening results of the J-Denver II, the overall sensitivity and specificity were 75.6% and 74.7%, respectively, when the ASQ-3 original criterion was used, and 56.3% and 93.0%, respectively, when the alternative criterion was used. CONCLUSIONS: This study quantified the psychometric profiles of the Japanese translations of 10 ASQ-3 questionnaires. We demonstrated the validity of the J-ASQ-3 and determined new cut-off scores. Further studies with larger samples from a greater range of locations are required to clarify the suitability of this tool for all Japanese children.

Cancer stem-like properties and gefitinib resistance are dependent on purine synthetic metabolism mediated by the mitochondrial enzyme MTHFD2.

Tumor recurrence is attributable to cancer stem-like cells (CSCs), the metabolic mechanisms of which currently remain obscure. Here, we uncovered the critical role of folate-mediated one-carbon (1C) metabolism involving mitochondrial methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) and its downstream purine synthesis pathway. MTHFD2 knockdown greatly reduced tumorigenesis and stem-like properties, which were associated with purine nucleotide deficiency, and caused marked accumulation of 5-aminoimidazole carboxamide ribonucleotide (AICAR)-the final intermediate of the purine synthesis pathway. Lung cancer cells with acquired resistance to the targeted drug gefitinib, caused by elevated expression of components of the ß-catenin pathway, exhibited increased stem-like properties and enhanced expression of MTHFD2. MTHFD2 knockdown or treatment with AICAR reduced the stem-like properties and restored gefitinib sensitivity in these gefitinib-resistant cancer cells. Moreover, overexpression of MTHFD2 in gefitinib-sensitive lung cancer cells conferred resistance to gefitinib. Thus, MTHFD2-mediated mitochondrial 1C metabolism appears critical for cancer stem-like properties and resistance to drugs including gefitinib through consumption of AICAR, leading to depletion of the intracellular pool of AICAR. Because CSCs are dependent on MTHFD2, therapies targeting MTHFD2 may eradicate tumors and prevent recurrence.

Trans-omic Analysis Reveals Selective Responses to Induced and Basal Insulin across Signaling, Transcriptional, and Metabolic Networks.

The concentrations of insulin selectively regulate multiple cellular functions. To understand how insulin concentrations are interpreted by cells, we constructed a trans-omic network of insulin action in FAO hepatoma cells using transcriptomic data, western blotting analysis of signaling proteins, and metabolomic data. By integrating sensitivity into the trans-omic network, we identified the selective trans-omic networks stimulated by high and low doses of insulin, denoted as induced and basal insulin signals, respectively. The induced insulin signal was selectively transmitted through the pathway involving Erk to an increase in the expression of immediate-early and upregulated genes, whereas the basal insulin signal was selectively transmitted through a pathway involving Akt and an increase of Foxo phosphorylation and a reduction of downregulated gene expression. We validated the selective trans-omic network in vivo by analysis of the insulin-clamped rat liver. This integrated analysis enabled molecular insight into how liver cells interpret physiological insulin signals to regulate cellular functions.

Fumarate Hydratase Deletion in Pancreatic ß Cells Leads to Progressive Diabetes.

We explored the role of the Krebs cycle enzyme fumarate hydratase (FH) in glucose-stimulated insulin secretion (GSIS). Mice lacking Fh1 in pancreatic ß cells (Fh1ßKO mice) appear normal for 6-8 weeks but then develop progressive glucose intolerance and diabetes. Glucose tolerance is rescued by expression of mitochondrial or cytosolic FH but not by deletion of Hif1α or Nrf2. Progressive hyperglycemia in Fh1ßKO mice led to dysregulated metabolism in ß cells, a decrease in glucose-induced ATP production, electrical activity, cytoplasmic [Ca2+]i elevation, and GSIS. Fh1 loss resulted in elevated intracellular fumarate, promoting succination of critical cysteines in GAPDH, GMPR, and PARK 7/DJ-1 and cytoplasmic acidification. Intracellular fumarate levels were increased in islets exposed to high glucose and in islets from human donors with type 2 diabetes (T2D). The impaired GSIS in islets from diabetic Fh1ßKO mice was ameliorated after culture under normoglycemic conditions. These studies highlight the role of FH and dysregulated mitochondrial metabolism in T2D.

Global metabolic reprogramming of colorectal cancer occurs at adenoma stage and is induced by MYC.

Cancer cells alter their metabolism for the production of precursors of macromolecules. However, the control mechanisms underlying this reprogramming are poorly understood. Here we show that metabolic reprogramming of colorectal cancer is caused chiefly by aberrant MYC expression. Multiomics-based analyses of paired normal and tumor tissues from 275 patients with colorectal cancer revealed that metabolic alterations occur at the adenoma stage of carcinogenesis, in a manner not associated with specific gene mutations involved in colorectal carcinogenesis. MYC expression induced at least 215 metabolic reactions by changing the expression levels of 121 metabolic genes and 39 transporter genes. Further, MYC negatively regulated the expression of genes involved in mitochondrial biogenesis and maintenance but positively regulated genes involved in DNA and histone methylation. Knockdown of MYC in colorectal cancer cells reset the altered metabolism and suppressed cell growth. Moreover, inhibition of MYC target pyrimidine synthesis genes such as CAD, UMPS, and CTPS blocked cell growth, and thus are potential targets for colorectal cancer therapy.

Undernourishment in utero Primes Hepatic Steatosis in Adult Mice Offspring on an Obesogenic Diet; Involvement of Endoplasmic Reticulum Stress.

In order to investigate the possible involvement of endoplasmic reticulum (ER) stress in the developmental origins of hepatic steatosis associated with undernourishment in utero, we herein employed a fetal undernourishment mouse model by maternal caloric restriction in three cohorts; cohort 1) assessment of hepatic steatosis and the ER stress response at 9 weeks of age (wks) before a high fat diet (HFD), cohort 2) assessment of hepatic steatosis and the ER stress response on a HFD at 17 wks, cohort 3) assessment of hepatic steatosis and the ER stress response at 22 wks on a HFD after the alleviation of ER stress with a chemical chaperone, tauroursodeoxycholic acid (TUDCA), from 17 wks to 22 wks. Undernourishment in utero significantly deteriorated hepatic steatosis and led to the significant integration of the ER stress response on a HFD at 17 wks. The alleviation of ER stress by the TUDCA treatment significantly improved the parameters of hepatic steatosis in pups with undernourishment in utero, but not in those with normal nourishment in utero at 22 wks. These results suggest the pivotal involvement of the integration of ER stress in the developmental origins of hepatic steatosis in association with undernourishment in utero.

Quantitative metabolome analysis profiles activation of glutaminolysis in glioma with IDH1 mutation.

Isocitrate dehydrogenase 1 (IDH1), which localizes to the cytosol and peroxisomes, catalyzes the oxidative decarboxylation of isocitrate to α-ketoglutarate (α-KG) and in parallel converts NADP(+) to NADPH. IDH1 mutations are frequently detected in grades 2-4 gliomas and in acute myeloid leukemias (AML). Mutations of IDH1 have been identified at codon 132, with arginine being replaced with histidine in most cases. Mutant IDH1 gains novel enzyme activity converting α-KG to D-2-hydroxyglutarate (2-HG) which acts as a competitive inhibitor of α-KG. As a result, the activity of α-KG-dependent enzyme is reduced. Based on these findings, 2-HG has been proposed to be an oncometabolite. In this study, we established HEK293 and U87 cells that stably expressed IDH1-WT and IDH1-R132H and investigated the effect of glutaminase inhibition on cell proliferation with 6-diazo-5-oxo-L-norleucine (DON). We found that cell proliferation was suppressed in IDH1-R132H cells. The addition of α-KG restored cell proliferation. The metabolic features of 33 gliomas with wild type IDH1 (IDH1-WT) and with IDH1-R132H mutation were examined by global metabolome analysis using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). We showed that the 2-HG levels were highly elevated in gliomas with IDH1-R132H mutation. Intriguingly, in gliomas with IDH1-R132H, glutamine and glutamate levels were significantly reduced which implies replenishment of α-KG by glutaminolysis. Based on these results, we concluded that glutaminolysis is activated in gliomas with IDH1-R132H mutation and that development of novel therapeutic approaches targeting activated glutaminolysis is warranted.

A role for cytosolic fumarate hydratase in urea cycle metabolism and renal neoplasia.

The identification of mutated metabolic enzymes in hereditary cancer syndromes has established a direct link between metabolic dysregulation and cancer. Mutations in the Krebs cycle enzyme, fumarate hydratase (FH), predispose affected individuals to leiomyomas, renal cysts, and cancers, though the respective pathogenic roles of mitochondrial and cytosolic FH isoforms remain undefined. On the basis of comprehensive metabolomic analyses, we demonstrate that FH1-deficient cells and tissues exhibit defects in the urea cycle/arginine metabolism. Remarkably, transgenic re-expression of cytosolic FH ameliorated both renal cyst development and urea cycle defects associated with renal-specific FH1 deletion in mice. Furthermore, acute arginine depletion significantly reduced the viability of FH1-deficient cells in comparison to controls. Our findings highlight the importance of extramitochondrial metabolic pathways in FH-associated oncogenesis and the urea cycle/arginine metabolism as a potential therapeutic target.

Inhibition of mitochondrial aconitase by succination in fumarate hydratase deficiency.

The gene encoding the Krebs cycle enzyme fumarate hydratase (FH) is mutated in hereditary leiomyomatosis and renal cell cancer (HLRCC). Loss of FH activity causes accumulation of intracellular fumarate, which can directly modify cysteine residues to form 2-succinocysteine through succination. We undertook a proteomic-based screen in cells and renal cysts from Fh1 (murine FH)-deficient mice and identified 94 protein succination targets. Notably, we identified the succination of three cysteine residues in mitochondrial Aconitase2 (ACO2) crucial for iron-sulfur cluster binding. We show that fumarate exerts a dose-dependent inhibition of ACO2 activity, which correlates with increased succination as determined by mass spectrometry, possibly by interfering with iron chelation. Importantly, we show that aconitase activity is impaired in FH-deficient cells. Our data provide evidence that succination, resulting from FH deficiency, targets and potentially alters the function of multiple proteins and may contribute to the dysregulated metabolism observed in HLRCC.

Design and synthesis of several small-size HTLV-I protease inhibitors with different hydrophilicity profiles.

The human T cell leukemia/lymphotropic virus type 1 (HTLV-I) is clinically associated with adult T cell leukemia/lymphoma, HTLV-I associated myelopathy/tropical spastic paraparesis, and a number of other chronic inflammatory diseases. To stop the replication of the virus, we developed highly potent tetrapeptidic HTLV-I protease inhibitors. In a recent X-ray crystallography study, several of our inhibitors could not form co-crystal complexes with the protease due to their high hydrophobicity. In the current study, we designed, synthesized and evaluated the HTLV-I protease inhibition potency of compounds with hydrophilic end-capping moieties with the aim of improving pharmaceutic and pharmacokinetic properties.

Maintaining potent HTLV-I protease inhibition without the P3-cap moiety in small tetrapeptidic inhibitors.

The human T cell lymphotropic/leukemia virus type 1 (HTLV-I) causes adult T cell lymphoma/leukemia. The virus is also responsible for chronic progressive myelopathy and several inflammatory diseases. To stop the manufacturing of new viral components, in our previous reports, we derived small tetrapeptidic HTLV-I protease inhibitors with an important amide-capping moiety at the P(3) residue. In the current study, we removed the P(3)-cap moiety and, with great difficulty, optimized the P(3) residue for HTLV-I protease inhibition potency. We discovered a very potent and small tetrapeptidic HTLV-I protease inhibitor (KNI-10774a, IC(50)=13 nM).

F-18 FDG accumulation in mucinous cystic neoplasm of pancreas.

We report a case of mucinous cystic neoplasm which showed FDG accumulation in its cyst wall. MRI revealed that this tumor had repeated intracystic hemorrhage. Inhomogeneous FDG accumulation was found in the cyst wall. The epithelium was focally denuded and ovarian-like stroma with macrophage migration, which phagocytosed red blood cells, and fibrosis were recognized on histopathological examination. These histopathological findings suggested that FDG accumulates not in the monolayer epithelium but in ovarian-like stroma with macrophage migration and fibrosis. Macrophage migration and fibrosis were considered to have contributed to FDG accumulation in this mucinous cystic neoplasm.

DNA microarray analysis in a mouse model for endometriosis and validation of candidate factors with human adenomyosis.

Gene expression profiling can be of benefit in identifying critical factors in the process of disease initiation and development. However, in endometriosis it has proven difficult to identify common genes between DNA microarray studies, presumably because of tissue homogeneity in lesions and diversity in the patients' conditions. We attempted DNA microarray analysis in a mouse model for endometriosis with stable lesions and a homogeneous genetic background. Data extracted from the mouse model was then evaluated in human tissues. Mice of the ddY strain underwent surgery to remove the left side of the uterine horn, and the uterine tissue was then minced into small segments and auto-transplanted onto the left peritoneum. After 8 weeks, most of the uterine grafts were enlarged and had regenerated lumens. Comparison of the intensity of mRNA expression between grafts and normal uteri showed that genes encoding immune regulators (e.g. CXCL10) and metabolic factors (e.g. calbindin D-28K) were highly up-regulated in the grafts. Strongly inhibited genes in the grafts included prostaglandin-related factors [e.g. prostaglandin E receptor 3 (subtype EP3) and prostaglandin I2 synthase]. Variation in some candidate factors detected in the mouse model was observed by immunohistochemical studies in human adenomyosis tissues. The gene list in the present study is available for re-evaluation of past studies and provides new candidate factors potentially involved in the pathogenesis of endometriosis.

Distinct role of growth hormone on epilepsy progression in a model of temporal lobe epilepsy.

Temporal lobe epilepsy is a common form of pharmacoresistant epilepsy, in which epileptogenic foci propagate to other regions of the brain from the area of the initial insult. The present study focused on epileptogenesis, that is, the development of the first foci inducing seizures in amygdala-kindled mice, a model of temporal lobe epilepsy, to find the molecular process promoting the formation of epileptogenic networks. The expression of growth hormone (GH) was up-regulated along neural circuits during the epileptogenesis, while there was no difference in the pituitary gland. The up-regulation was associated with increased phosphorylation/activation of signal transducer and activator of transcription 5 and expression of the Serum Response Element-regulated genes, FBJ osteosarcoma oncogene, early growth response 1, and Jun-B oncogene, suggesting that expression of GH leads to GH signaling in the hippocampus and cortex. Furthermore, the administration of the hormone into the hippocampus markedly enhanced the progression of kindling. The administration of an inhibitor of its secretion into the hippocampus elicited a delay in the progression. Our results demonstrate directly that regulation via growth hormone has a robust impact in epileptogenesis.