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Krabbe disease is a rare, inherited neurodegenerative disease due to impaired lysosomal β-galactosylceramidase (GALC) activity and formation of neurotoxic β-galactosylsphingosine ('psychosine'). We investigated substrate reduction therapy with a novel brain-penetrant inhibitor of galactosylceramide biosynthesis, RA 5557, in twitcher mice that lack GALC activity and model Krabbe disease. This thienopyridine derivative selectively inhibits uridine diphosphate-galactose glycosyltransferase 8 (UGT8), the final step in the generation of galactosylceramides which are precursors of sulphatide and, in the pathological lysosome, the immediate source of psychosine. Administration of RA 5557, reduced pathologically elevated psychosine concentrations (72-86%) in the midbrain and cerebral cortex in twitcher mice: the inhibitor decreased galactosylceramides by about 70% in midbrain and cerebral cortex in mutant and wild type animals. Exposure to the inhibitor significantly decreased several characteristic inflammatory response markers without causing apparent toxicity to myelin-producing cells in wild type and mutant mice; transcript abundance of oligodendrocyte markers MBP (myelin basic protein) and murine UGT8 was unchanged. Administration of the inhibitor before conception and during several breeding cycles to mice did not impair fertility and gave rise to healthy offspring. Nevertheless, given the unchanged lifespan, it appears that GALC has critical functions in the nervous system beyond the hydrolysis of galactosylceramide and galactosylsphingosine. Our findings support further therapeutic exploration of orally active UGT8 inhibitors in Krabbe disease and related galactosphingolipid disorders. The potent thienopyridine derivative with effective target engagement here studied appears to have an acceptable safety profile in vivo; judicious dose optimization will be needed to ensure efficacious clinical translation.

Alexander disease (AxD) is a rare and fatal neurodegenerative disorder caused by mutations in the gene encoding glial fibrillary acidic protein (GFAP). In this report, a mouse model of AxD (GFAPTg;Gfap+/R236H) was analyzed that contains a heterozygous R236H point mutation in murine Gfap as well as a transgene with a GFAP promoter to overexpress human GFAP. Using label-free quantitative proteomic comparisons of brain tissue from GFAPTg;Gfap+/R236H versus wild-type mice confirmed upregulation of the glutathione metabolism pathway and indicated proteins were elevated in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which had not been reported previously in AxD. Relative protein-level differences were confirmed by a targeted proteomics assay, including proteins related to astrocytes and oligodendrocytes. Of particular interest was the decreased level of the oligodendrocyte protein, 2-hydroxyacylsphingosine 1-beta-galactosyltransferase (Ugt8), since Ugt8-deficient mice exhibit a phenotype similar to GFAPTg;Gfap+/R236H mice (e.g., tremors, ataxia, hind-limb paralysis). In addition, decreased levels of myelin-associated proteins were found in the GFAPTg;Gfap+/R236H mice, consistent with the role of Ugt8 in myelin synthesis. Fabp7 upregulation in GFAPTg;Gfap+/R236H mice was also selected for further investigation due to its uncharacterized association to AxD, critical function in astrocyte proliferation, and functional ability to inhibit the anti-inflammatory PPAR signaling pathway in models of amyotrophic lateral sclerosis (ALS). Within Gfap+ astrocytes, Fabp7 was markedly increased in the hippocampus, a brain region subjected to extensive pathology and chronic reactive gliosis in GFAPTg;Gfap+/R236H mice. Last, to determine whether the findings in GFAPTg;Gfap+/R236H mice are present in the human condition, AxD patient and control samples were analyzed by Western blot, which indicated that Type I AxD patients have a significant fourfold upregulation of FABP7. However, immunohistochemistry analysis showed that UGT8 accumulates in AxD patient subpial brain regions where abundant amounts of Rosenthal fibers are located, which was not observed in the GFAPTg;Gfap+/R236H mice., Graphical abstract, Highlights • Models of AxD provide insight into functions of astrocytes related to neuropathology. • PPAR pathway found upregulated in AxD mice may be neuroprotective. Fatty acid binding protein (Fabp7) was upregulated in AxD mice and human CNS samples. • Depleted levels in the classical constituents of myelin were observed in AxD mice. • UGT8 may be related to myelin deficits in AxD., In Brief The article contains the first whole brain proteomic survey from a mouse model of Alexander disease (AxD). Several novel findings include activation of the PPAR signaling pathway, which has been reported to be protective in models of amyotrophic lateral sclerosis (ALS). Another finding related to the gliosis phenotype in AxD mice was the upregulation of fatty acid binding protein 7 (FABP7), which induces an NF-κB inflammatory response and counteracts the anti-inflammatory effects of PPAR signaling.

On the role of galectin-4 in (re)myelination and multiple sclerosisMultiple sclerosis (MS) is the most common demyelinating diseases of the central nervous system (CNS). Remyelination is a regenerative process and is most efficient when recruited oligodendrocyte progenitor cells (OPCs) mature and re-supply the denuded axon with myelin. A tight regulation and cooperative communication between neurons and glial cells contribute to successful remyelination. In MS, cell dysfunction and/or an inhibitory environment leads to impaired differentiation of OPCs into myelinating oligodendrocytes. The persistent loss of neuroprotective and insulating myelin results in neurological deficits and disease progression.Previous findings indicate that secreted neuronal galectin-4 negatively regulates the timing of OPC differentiation during development. Using experimental models for de- and/or remyelination, we revealed that neuronal galectin-4 is transiently re-expressed on demyelinated axons, while persistently present on axons in inactive MS lesions. In addition, in the demyelinated areas galectin-4 was present in microglia and macrophages. Whether microglia and macrophages are cellular sources of galectin-4 remains to be determined. Preliminary data indicate that a distinct isoform of galectin-4 may exist in the CNS. Surprisingly, in contrast to their individual activities as negative regulators or (re)myelination, our findings indicate that the simultaneous presence of galectin-4 and fibronectin promoted myelin membrane formation. To obtain more insight in the underlying mechanism, we identified at the cell surface of immature oligodendrocytes, two galectin-4 binding sites, UGT8 and contactin-1. UGT8 is an enzyme responsible for the synthesis of the major myelin lipid galactosylceramide. Hence, modulating galectin-4 signaling in MS lesions, among others by modulating its interactions with UGT8 and contactin-1, may be attractive approaches to promote remyelination.

UDP-glycosyltransferases (UGTs) catalyze the covalent addition of sugars to small lipophilic chemicals and are associated with a wide range of diseases including cancer. The human genome contains 22 UGT genes which could be classified into four families: UGT1, UGT2, UGT3, and UGT8. The UGT8 family contains only one member which utilizes UDP galactose to galactosidate ceramide. Although higher UGT8 mRNA was observed in some types of cancer, its pathological significances remain elusive. Here, by integrating the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and the Genotype-Tissue Expression (GTEx) databases, we showed that UGT8 was selectively highly expressed in non-small cell lung cancer (NSCLC) and associated with worse prognosis. The transcription factor SOX9 promoted UGT8 expression in NSCLC by recognizing two putative response elements localized on the promoter region of UGT8. Silencing UGT8 impaired glycolysis and reduced the malignancy of NSCLC cells both in vitro and in vivo. On the contrary, inhibition of glycolysis by 2-deoxy- d -glucose (2-DG) significantly impaired the pro-proliferation function of UGT8 in NSCLC cells. In conclusion, our results suggest that UGT8 maintains the malignancy of NSCLC mainly via enhanced glycolysis and provides a promising therapeutic target for NSCLC.

The human UDP-glycosyltransferase (UGTs) superfamily has 22 functional enzymes that play a critical role in the metabolism of small lipophilic compounds, including carcinogens, drugs, steroids, lipids, fatty acids, and bile acids. The expression profiles of UGT genes in human cancers and their impact on cancer patient survival remains to be systematically investigated. In the present study, a comprehensive analysis of the RNAseq and clinical datasets of 9514 patients from 33 different TCGA (the Genome Cancer Atlas) cancers demonstrated cancer-specific UGT expression profiles with high interindividual variability among and within individual cancers. Notably, cancers derived from drug metabolizing tissues (liver, kidney, gut, pancreas) expressed the largest number of UGT genes (COAD, KIRC, KIRP, LIHC, PAAD), six UGT genes (1A6, 1A9, 1A10, 2A3, 2B7, UGT8) showed high expression in five or more different cancers. Kaplan–Meier plots and logrank tests revealed that six UGT genes were significantly associated with increased overall survival (OS) rates [UGT1A1 (LUSC), UGT1A6 (ACC), UGT1A7 (ACC), UGT2A3 (KIRC), UGT2B15 (BLCA, SKCM)] or decreased OS rates [UGT2B15 (LGG), UGT8 (UVM)] in specific cancers. Finally, differential expression analysis of 611 patients from 12 TCGA cancers identified 16 UGT genes (1A1, 1A3, 1A6, 1A7, 1A8, 1A9, 1A10, 2A1, 2A3, 2B4, 2B7, 2B11, 2B15, 3A1, 3A2, UGT8) that were up/downregulated in at least one cancer relative to normal tissues. In conclusion, our data show widespread expression of UGT genes in cancers, highlighting the capacity for intratumoural drug metabolism through the UGT conjugation pathway. The data also suggests the potentials for specific UGT genes to serve as prognostic biomarkers or therapeutic targets in cancers.

Su-Jeong Kim,1,* Jae-Ho Lee,2,* Woo-Jae Park,1 Shin Kim3– 5 1Department of Biochemistry, College of Medicine, Gachon University, Yeonsu-gu, Incheon, 21999, Republic of Korea; 2Department of Anatomy, School of Medicine, Keimyung University, Dalseo-gu, Daegu, 42601, Republic of Korea; 3Department of Immunology, School of Medicine, Keimyung University, Dalseo-gu, Daegu, 42601, Republic of Korea; 4Institute of Medical Science, Keimyung University, Dalseo-gu, Daegu, 42601, Republic of Korea; 5Institute for Cancer Research, Keimyung University Dongsan Medical Center, Dalseo-gu, Daegu, 42601, Republic of Korea*These authors contributed equally to this workCorrespondence: Shin Kim Email god98005@dsmc.or.krIntroduction: Sphingolipid metabolism is a highly controlled process that is involved in regulating bioactive lipid signaling pathways and serves important roles in several cellular processes in breast cancer. Invasive ductal carcinoma (IDC), which is characterized by the malignant proliferation of the ductal epithelium and stromal invasion, is the most common type of breast cancer. Recent advances in genetic research have accelerated the discovery of novel prognostic factors and therapeutic targets for the disease. The aim of the present study was to investigate the expression and prognostic significance of sphingolipid metabolism-related genes in female IDC.Methods: The present study used gene expression RNAseq data obtained from The Cancer Genome Atlas breast invasive carcinoma (TCGA BRCA) datasets.Results: Sphingolipid metabolism-related genes exhibited dysregulated mRNA expression levels in IDC. The Student’s t-test revealed that SMPDL3B, B4GALNT1, LPAR2, and LASS2 were significantly upregulated, while LASS3, LPAR1, B4GALT6, GAL3ST1, HPGD, ST8SIA1, UGT8, and S1PR1 were significantly downregulated in female IDC tissues compared with normal solid tissues. Kaplan–Meier survival analyses revealed that high SMPDL3B mRNA expression levels were associated with good prognosis in female IDC, suggesting that SMPDL3B plays a tumor suppressor role. To the best of our knowledge, the present study was the first to report that dysregulated expressions of SMPDL3B are significantly associated with age, estrogen receptor status, progesterone receptor status, and histological subtype.Conclusion: Taken together, our study indicated that SMPDL3B may have a pathophysiological role and serve as a novel prognostic biomarker in IDC.Keywords: SMPDL3B, sphingolipid metabolism, invasive ductal carcinoma, TCGA

Lung cancer causes more deaths than any other cancer. Sphingolipids encompass metabolically interconnected species whose balance has pivotal effects on proliferation, migration, and apoptosis. In this study, we paralleled quantification of sphingolipid species with quantitative (q)PCR analyses of metabolic enzymes in order to identify dysregulated routes of sphingolipid metabolism in different subtypes of lung cancers. Lung samples were submitted to histopathological reexamination in order to confirm cancer type/subtype, which included adenocarcinoma histological subtypes and squamous cell and neuroendocrine carcinomas. Compared with benign lesions and tumor-free parenchyma, all cancers featured decreased sphingosine-1-phosphate and SMs. qPCR analyses evidenced differential mechanisms leading to these alterations between cancer types, with neuroendocrine carcinomas upregulating SGPL1, but CERT1 being downregulated in adenocarcinomas and squamous cell carcinomas. 2-Hydroxyhexosylceramides (2-hydroxyHexCers) were specifically increased in adenocarcinomas. While UDP-glycosyltransferase 8 (UGT8) transcript levels were increased in all cancer subtypes, fatty acid 2-hydroxylase (FA2H) levels were higher in adenocarcinomas than in squamous and neuroendocrine carcinomas. As a whole, we report differing mechanisms through which all forms of lung cancer achieve low SM and lysosphingolipids. Our results also demonstrate that FA2H upregulation is required for the accumulation of 2-hydroxyHexCers in lung cancers featuring high levels of UGT8.

Hypomyelination in the central nerves system (CNS) is one of the most obviously pathological features in Niemann-Pick Type C disease (NPC), which is a rare neurodegenerative disorder caused by mutations in the NPC intracellular cholesterol transporter 1 or 2 (Npc1 or Npc2). Npc1 plays key roles in both neurons and oligodendrocytes during myelination, however, the linkage between the disturbed cholesterol transport and inhibited myelination is unrevealed. In this study, mass spectrometry (MS)-based differential quantitative proteomics was applied to compare protein composition in the corpus callosum between wild type (WT) and NPC mice. In total, 3009 proteins from both samples were identified, including myelin structural proteins, neuronal proteins, and astrocyte-specific proteins. In line to hypomyelination, our data revealed downregulation of myelin structural and indispensable proteins in Npc1 mutant mice. Notably, the reduced ceramide synthase 2 (Cers2), UDP glycosyltransferase 8 (Ugt8), and glycolipid transfer protein (Gltp) indicate the altered sphingolipid metabolism in the disease and the involvement of Gltp in myelination. The identification of most reported myelin structural proteins and proteins from other cell types advocates the use of the corpus callosum to investigate proteins in different cell types that regulate myelination. Electronic supplementary material The online version of this article (10.1186/s13041-019-0440-9) contains supplementary material, which is available to authorized users.

Mutations in glycosyltransferases have been implicated in the pathogenesis of neurodegenerative diseases, including ALS and Alzheimer’s disease. Moll et al. review the existing literature, with a focus on mechanisms connecting glycosyltransferase dysfunction to neurodegeneration. They also provide new evidence that mutations in the glycosyltransferase EOGT are associated with sporadic ALS., Glycosyltransferases represent a large family of enzymes that catalyse the biosynthesis of oligosaccharides, polysaccharides, and glycoconjugates. A number of studies have implicated glycosyltransferases in the pathogenesis of neurodegenerative diseases but differentiating cause from effect has been difficult. We have recently discovered that mutations proximal to the substrate binding site of glycosyltransferase 8 domain containing 1 (GLT8D1) are associated with familial amyotrophic lateral sclerosis (ALS). We demonstrated that ALS-associated mutations reduce activity of the enzyme suggesting a loss-of-function mechanism that is an attractive therapeutic target. Our work is the first evidence that isolated dysfunction of a glycosyltransferase is sufficient to cause a neurodegenerative disease, but connection between neurodegeneration and genetic variation within glycosyltransferases is not new. Previous studies have identified associations between mutations in UGT8 and sporadic ALS, and between ST6GAL1 mutations and conversion of mild cognitive impairment into clinical Alzheimer’s disease. In this review we consider potential mechanisms connecting glycosyltransferase dysfunction to neurodegeneration. The most prominent candidates are ganglioside synthesis and impaired addition of O-linked β-N-acetylglucosamine (O-GlcNAc) groups to proteins important for axonal and synaptic function. Special consideration is given to examples where genetic mutations within glycosyltransferases are associated with neurodegeneration in recognition of the fact that these changes are likely to be upstream causes present from birth.

Objective Major depressive disorder (MDD) arises from a combination of genetic and environmental risk factors and DNA methylation is one of the molecular mechanisms through which these factors can manifest. However, little is known about the epigenetic signature of MDD in brain tissue. This study aimed to investigate associations between brain tissue-based DNA methylation and late-life MDD. Methods We performed a brain epigenome-wide association study (EWAS) of late-life MDD in 608 participants from the Religious Order Study and the Rush Memory and Aging Project (ROS/MAP) using DNA methylation profiles of the dorsal lateral prefrontal cortex generated using the Illumina HumanMethylation450 Beadchip array. We also conducted an EWAS of MDD in each sex separately. Results We found epigenome-wide significant associations between brain tissue-based DNA methylation and late-life MDD. The most significant and robust association was found with altered methylation levels in the YOD1 locus (cg25594636, p value = 2.55 × 10−11; cg03899372, p value = 3.12 × 10−09; cg12796440, p value = 1.51 × 10−08, cg23982678, p value = 7.94 × 10−08). Analysis of differentially methylated regions (p value = 5.06 × 10−10) further confirmed this locus. Other significant loci include UGT8 (cg18921206, p value = 1.75 × 10−08), FNDC3B (cg20367479, p value = 4.97 × 10−08) and SLIT2 (cg10946669, p value = 8.01 × 10−08). Notably, brain tissue-based methylation levels were strongly associated with late-life MDD in men more than in women. Conclusions We identified altered methylation in the YOD1, UGT8, FNDC3B, and SLIT2 loci as new epigenetic factors associated with late-life MDD. Furthermore, our study highlights the sex-specific molecular heterogeneity of MDD.

Cao et al. show that UGT8 promotes BLBC progression through activating sulfatide–αVβ5 axis. ZA is identified as a direct inhibitor of UGT8 and suppresses BLBC progression, suggesting that inhibition of UGT8 offers a promising opportunity for treating BLBC., Basal-like breast cancer (BLBC) is associated with a poor clinical outcome as a result of the few treatment options and poor therapeutic response. Here, we report that elevated expression of urine diphosphate–galactose ceramide galactosyltransferase (UGT8) specifically occurs in BLBC and predicts poor prognosis in breast cancer patients. UGT8 expression is transcriptionally up-regulated by Sox10, triggering the sulfatide biosynthetic pathway; increased sulfatide activates integrin αVβ5-mediated signaling that contributes to BLBC progression. UGT8 expression promotes, whereas UGT8 knockdown suppresses tumorigenicity and metastasis. Importantly, we identify that zoledronic acid (ZA), a marketed drug for treating osteoporosis and bone metastasis, is a direct inhibitor of UGT8, which blocks the sulfatide biosynthetic pathway. Significantly, a clinically achievable dosage of ZA exhibits apparent inhibitory effect on migration, invasion, and lung metastasis of BLBC cells. Together, our study suggests that UGT8 is a potential prognostic indicator and druggable target of BLBC and that pharmacologic inhibition of UGT8 by ZA offers a promising opportunity for treating this challenging disease.

Krabbe's disease is a neurodegenerative disorder caused by deficiency of galactocerebrosidase activity that affects the myelin sheath of the nervous system, involving dysfunctional metabolism of sphingolipids. It has no cure. Because substrate inhibition therapy has been shown to be effective in some human lysosomal storage diseases, we hypothesize that a substrate inhibition therapeutic approach might be appropriate to allow correction of the imbalance between formation and breakdown of glycosphingolipids and to prevent pathological storage of psychosine. The enzyme responsible for the biosynthesis of galactosylceramide and psychosine is uridine diphosphate-galactose ceramide galactosyltransferase (2-hydroxyacylsphingosine 1-β-galactosyltransferase; UGT8; EC 2.4.1.45), which catalyzes the transferring of galactose from uridine diphosphate-galactose to ceramide or sphingosine, an important step of the biosynthesis of galactosphingolipids. Because some bisphosphonates have been identified as selective galactosyltransferase inhibitors, we verify the binding affinity to a generated model of the enzyme UGT8 and investigate the molecular mechanisms of UGT8-ligand interactions of the bisphosphonate zoledronate by a multistep framework combining homology modeling, molecular docking, and molecular dynamics simulations. From structural information on UGTs' active site stereochemistry, charge density, and access through the hydrophobic environment, the molecular docking procedure allowed us to identify zoledronate as a potential inhibitor of human ceramide galactosyltransferase. More importantly, zoledronate derivates were designed through computational modeling as putative new inhibitors. Experiments in vivo and in vitro have been planned to verify the possibility of using zoledronate and/or the newly identified inhibitors of UGT8 for a substrate inhibition therapy useful for treatment of Krabbe's disease and/or other lysosomal disorders. © 2016 Wiley Periodicals, Inc.

Background Oligodendrocytes (OLs) and myelin are critical for normal brain function and have been implicated in neurodegeneration. Several lines of evidence including neuroimaging and neuropathological data suggest that Alzheimer’s disease (AD) may be associated with dysmyelination and a breakdown of OL-axon communication. Methods In order to understand this phenomenon on a molecular level, we systematically interrogated OL-enriched gene networks constructed from large-scale genomic, transcriptomic and proteomic data obtained from human AD postmortem brain samples. We then validated these networks using gene expression datasets generated from mice with ablation of major gene expression nodes identified in our AD-dysregulated networks. Results The robust OL gene coexpression networks that we identified were highly enriched for genes associated with AD risk variants, such as BIN1 and demonstrated strong dysregulation in AD. We further corroborated the structure of the corresponding gene causal networks using datasets generated from the brain of mice with ablation of key network drivers, such as UGT8, CNP and PLP1, which were identified from human AD brain data. Further, we found that mice with genetic ablations of Cnp mimicked aspects of myelin and mitochondrial gene expression dysregulation seen in brain samples from patients with AD, including decreased protein expression of BIN1 and GOT2. Conclusions This study provides a molecular blueprint of the dysregulation of gene expression networks of OL in AD and identifies key OL- and myelination-related genes and networks that are highly associated with AD. Electronic supplementary material The online version of this article (10.1186/s13024-017-0219-3) contains supplementary material, which is available to authorized users.

We studied the altered molecular species of lipids in brain and liver tissues, and fibroblasts from patients with Zellweger syndrome (ZS). ZS cerebellum samples contained a higher amount of sphingomyelin with shorter chain fatty acids compared to that in normal controls. The amount of phosphatidylethanolamine (PE) was less than half of that in controls, with the absence of the PE-type of plasmalogen. Gangliosides were accumulated in the brains and fibroblasts of ZS patients. To investigate whether or not impaired beta-oxidation of very long chain fatty acids and/or plasmalogen synthesis affects glycolipids metabolism, RNAi of peroxisomal acylCo-A oxidase (ACOX1) and glyceronephosphate O-acyltransferase (GNPAT) was performed using cultured neural cells. In neuronal F3-Ngn1 cells, ACOX1 and GNPAT silencing up-regulated ceramide galactosyltransferase (UGT8) mRNA expression, and down-regulated UDP-glucose ceramide glucosyltransferase (UGCG). These results suggest that both impaired beta-oxidation of very long chain fatty acids and plasmalogen synthesis affect glycolipid metabolism in neuronal cells.

Thirty-two canine mammary tubulopapillary carcinomas and 14 simple adenomas were studied by immunohistochemistry for the expression of UDP-galactose:ceramide galactosyltransferase (UGT8). The majority of tissue specimens (57%) representing adenomas had no or weak reaction with anti-UGT8 antibodies (0-2 pts according to IRS scale) in comparison to the majority of carcinomas (90%) which stained with high intensities (3-9 pts according to IRS scale). When the average values of the reaction intensities (IRS) for malignant and benign tumors were compared, using the Mann-Whitney U-test, significant differences in UGT8 expression between them were found (P < 0.001). Mammary tubulopapillary carcinomas were further analyzed by IHC and the same rabbit polyclonal antibody directed against UGT8 according to their malignancy grade. It was found that the level of UGT8 increased in tumor specimens together with their grading. A comparison of the average values of the reaction intensity (IRS scale) revealed a significant difference (Mann-Whitney U-test, P < 0.05) in UGT8 expression between tumors representing malignancy grades G3 and G1. Based on the obtained results, it is proposed that UGT8 is associated with malignancy of canine mammary gland cells and may have a potential value as a diagnostic marker.

EBV-miR-BART1 has been found to be highly expressed in some cancers including nasopharyngeal carcinoma (NPC), but its exact roles in the pathogenesis of NPC remain unclear. Here, we did RNA deep sequencing to compare the gene expression profile between EBV-miR-BART1-expressing CNE1 cells and the control cells to determine the possible effects of EBV-miR-BART1 in NPC. Gene expression profiling analysis unexpectedly showed a significant number of up- and down-modulated metabolism-associated genes, such as G6PD, SAT1, ASS1, PAST1, FUT1, SGPL1, DHRS3, B4GALT1, PHGDH, IDH2, PISD, UGT8, LDHB and GALNT1, in EBV-miR-BART1-expressing NPC cells, which were next confirmed by RT-qPCR. Moreover, of these metabolism-genes, PSAT1 and PHGDH expression levels were significantly upregulated and most of other genes were obviously up-expressed in NPC specimens compared with chronic nasopharyngitis (CNP) tissues. Collectively, we for the first time found the effects of EBV-miR-BART1 on the expression of mechanism-associated genes in NPC, suggesting a novel role of EBV-miR-BART1 in cancer metabolism, which remains to be fully elucidated.

Ultrasound (US) stimulated microbubbles (MB) is a new treatment approach that sensitizes cancer cells to radiation (XRT). The molecular pathways in this response remain unelucidated, however, previous data has supported a role for cell membrane-metabolism related pathways including an up regulation of UDP glycosyltransferase 8 (UGT8), which catalyzes the transfer of galactose to ceramide, a lipid that is associated with the induction of apoptotic signalling. In this study, the role of UGT8 in responses of prostate tumours to ultrasound-stimulated microbubble radiation enhancement therapy is investigated. Experiments were carried out with cells in vitro and tumours in vivo in which UGT8 levels had been up regulated or down regulated. Genetically modified PC3 cells were treated with XRT, US+MB, or a combination of XRT+US+MB. An increase in the immunolabelling of ceramide was observed in cells where UGT8 was down-regulated as opposed to cells where UGT8 was either not regulated or was up-regulated. Clonogenic assays have revealed a decreased level of cellular survival with the down-regulation of UGT8. Xenograft tumours generated from stably transfected PC3 cells were also treated with US+MB, XRT or US+MB+XRT. Histology demonstrated more cellular damage in tumours with down-regulated UGT8 in comparison with control tumours. In contrast, tumours with up-regulated UGT8 had less damage than control tumours. Power Doppler imaging indicated a reduction in the vascular index with UGT8 down-regulation and photoacoustic imaging revealed a reduction in oxygen saturation. This was contrary to when UGT8 was up regulated. The down regulation of UGT8 led to the accumulation of ceramide resulting in more cell death signalling and therefore, a greater enhancement of radiation effect when vascular disruption takes place through the use of ultrasound-stimulated microbubbles.

Ceramide galactosyltransferase (UGT8) is an enzyme that regulates the synthesis of sphingolipids of the myelin sheath in nervous systems. The protein raises an increasing research interest as a potential marker of cancer progression in various organs. In the present study we seek to determine whether UGT8 could play a role of a therapeutic marker in non-small cell lung carcinoma (NSCLC). We addressed the issue by examining the intensity of UGT8 expression in tissue specimens of primary and corresponding metastatic lung tumors in 19 NSCLC patients undergoing surgery. The methodology was one of immunohistochemical tissue staining using light microscopy. The findings were that the majority of both lung primary and metastatic tumor tissues were positive in UGT8 signals. The cytoplasmic expression of UGT8 was found in 68.4 % of cases of primary tumors and 82.2 % of metastases, with a positive correlation between the UGT8 expression in both tumor tissues. The normal tissue adjacent to tumors showed no positive UGT8 staining. However, we failed to find any appreciable difference in UGT8 expression depending on the clinical stage of NSCLC or lymph node involvement. Nor was there any association between UGT8 expression in tumor tissues and patients’ survival time. We conclude that it is unlikely that therapeutic targeting of UGT8 could inhibit cell proliferation and invasion of NSCLC. UGT8, although enhanced in NSCLC tissues, does not meet the criteria of a lung tumor marker. Thus, UGT8 cannot be considered as having diagnostic or therapeutic utility in NSCLC. The pathophysiological meaning of enhanced expression of UGT8 in lung cancer remains to be explored in further studies.

application/pdf, UDP-glycosyltransferase (UGT) catalyzes the transfer of glycosyl groups (e.g., glucuronic acid) to exogenous or endogenous chemicals and plays an important role in conjugation reactions. In vertebrates, UGT genes are divided into 5 families: UGT1, UGT2, UGT3, UGT5, and UGT8. Among these UGT enzymes, UGT1 and UGT2 enzymes are known to be important xenobiotic metabolizing enzymes in mammals. However, little is known about UGT1 and UGT2 genes in avian species. In this study, we therefore aimed to classify avian UGT1 and UGT2 genes based on their evolutionary relationships. We also investigated the association between UGT molecular evolution and ecological factors, specifically feeding habits, habitat, and migration. By examining the genomes of 43 avian species with differing ecology, we showed that avian UGT1E genes are divided into 6 groups and UGT2 genes into 3 groups. Correlations between UGT gene count and ecological factors suggested that the number of UGT1E genes is decreasing in carnivorous species. Estimates of selection pressure also support the hypothesis that diet influenced avian UGT1E gene evolution, similar to mammalian UGT1A and UGT2B genes.

Background: It was shown recently on the level of gene expression that UGT8, coding UDP-galactose:ceramide galactosyltransferase, is one of six genes whose elevated expression correlated with a significantly increased the risk of lung metastases in breast cancer patients. In this study primary tumours and their lung metastases as well as breast cancer cell lines were analysed for UGT8 expression at the protein level. Methods: Expression of UGT8 in breast cancer tissue specimens and breast cancer cell lines was analysed using IHC, real-time PCR and Western blotting. Results: Comparison of the average values of the reaction intensities (IRS scale) showed a significant difference in UGT8 expression between (1) primary and metastatic tumours (Mann–Whitney U, P

Sphingolipids are bioactive lipids implicated in apoptosis, cell survival and proliferation. We analyzed the prognostic value of enzymes from sphingolipid metabolism in breast cancer.Differences in expression of ceramide galactosyl transferase (UGT8), ceramide kinase (CERK), and Ganglioside GD3-Synthase (ST8SIA1) in breast cancer cells were investigated by using microarray data of 1,581 tumor samples.UGT8, CERK, and ST8SIA1 were associated with poor pathohistological grading (P0.001). High CERK expression was correlated with ErbB2 status (P = 0.006). Among ER positive breast cancers a significant worse prognosis for patients with tumors showing low ST8SIA1 and UGT8 expression was observed. In the ER negative subgroup those samples with high CERK expression displayed a worse prognosis. In a multivariate analysis only ST8SIA1 and tumor size remained significant.Our experiments reveal that expression of enzymes from the sphingolipid metabolism has prognostic implications in breast cancer.

As the field of glycobiology grows, important roles for glycolipids and glycoproteins in neurological disorders are being increasingly appreciated. However, few studies have explored the involvement of these molecules in the pathology of psychiatric illnesses. We investigated molecular differences related to glycobiology in subjects with schizophrenia by analyzing gene expression profiles using a focused glycogene chip, a custom-designed oligonucleotide array containing genes encoding proteins related to glycobiology, including glycosyltransferases, carbohydrate-binding proteins, proteoglycans, and adhesion molecules. We measured expression profiles in prefrontal cortical (BA46) samples from schizophrenic subjects and matched controls. We find differential expression of genes particularly related to glycosphingolipid/sphingolipid metabolism and N- and O-linked glycan biosynthesis in subjects with schizophrenia. Expression decreases of seven genes associated with these pathways, UGT8, SGPP1, GALC, B4GALT6, SPTLC2, ASAH1, and GAL3ST1, were validated by quantitative PCR in schizophrenic subjects with short-term illness. Only one of these genes, SPTLC2, showed differential expression in chronic schizophrenic subjects, although an increase in expression was observed. Covariate analysis showed that the expression of five of these genes was significantly positively correlated with age in schizophrenic, but not control, subjects. These changing patterns of expression could represent an adaptive response to pathology with disease progression or a compensatory effect of antipsychotic medication, although no significant correlations between gene expression levels and drug doses were observed. Disruption of sphingolipid metabolism early in illness could result in widespread downstream effects encompassing diverse pathological deficits already described in schizophrenia, especially those involving myelination and oligodendrocyte function; hence, this system may represent an important link in schizophrenia pathology.

Breast cancer is the most common cancer in women worldwide. Elucidation of underlying biology and molecular pathways is necessary for improving therapeutic options and clinical outcomes. CLN3 protein (CLN3p), deficient in neurodegenerative CLN3 disease is anti-apoptotic, and defects in the CLN3 gene cause accelerated apoptosis of neurons in CLN3 disease and upregulation of ceramide. Dysregulated apoptotic pathways are often implicated in the development of the oncogenic phenotype. Predictably, CLN3 mRNA expression and CLN3 protein were upregulated in a number of human and murine breast cancer cell lines. Here, we determine CLN3 expression in non-tumor vs. tumor samples from fresh and formalin-fixed/paraffin-embedded (FFPE) breast tissue and analyze the association between CLN3 overexpression and different clinicopathological characteristics of breast cancer patients. Additionally, gene expression of 28 enzymes involved in sphingolipid metabolism was determined. CLN3 mRNA is overexpressed in tumor vs. non-tumor breast tissue from FFPE and fresh samples, as well as in mouse MCF7 breast cancer compared to MCF10A normal cells. Of the clinicopathological characteristics of tumor grade, age, menopause status, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), only absence of HER2 expression correlated with CLN3 overexpression. Sphingolipid genes for ceramide synthases 2 and 6 (CerS2; CerS6), delta(4)-desaturase sphingolipid 2 (DEGS2) and acidic sphingomyelinase (SMPD1) displayed higher expression levels in breast cancer vs. control tissue, whereas, ceramide galactosyltransferase (UGT8) was underexpressed in breast cancer samples. CLN3 may be a novel molecular target for cancer drug discovery with the goal of modulation of ceramide pathways.

It was recently proposed that UDP-galactose:ceramide galactosyltransferase (UGT8), enzyme responsible for synthesis of galactosylceramide (GalCer), is a significant index of tumor aggressiveness and a potential marker for the prognostic evaluation of lung metastases in breast cancer. To further reveal the role of UGT8 and GalCer in breast cancer progression, tumorigenicity and metastatic potential of control MDA-MB-231 cells (MDA/LUC) and MDA-MB-231 cells (MDA/LUC-shUGT8) with highly decreased expression of UGT8 and GalCer after stable expression of shRNA directed against UGT8 mRNA was studied in vivo in athymic nu/nu mice. Control MDA/LUC cells formed tumors and metastatic colonies much more efficiently in comparison to MDA/LUC-shUGT8 cells with suppressed synthesis of GalCer after their, respectively, orthotopic and intracardiac transplantation. These findings indicate that UGT8 and GalCer have a profound effect on tumorigenic and metastatic properties of breast cancer cells. In accordance with this finding, immunohistochemical staining of tumor specimens revealed that high expression of UGT8 accompanied by accumulation of GalCer in MDA-MB-231 cells is associated with a much higher proliferative index and a lower number of apoptotic cells in comparison to the MDA/LUC-shUGT8 cells. In addition, it was found that expression of UGT8 in MDA-MB-231 cells increased their resistance to apoptosis induced by doxorubicin in vitro. Therefore, these data suggest that accumulation of GalCer in tumor cells inhibits apoptosis, which would facilitates metastatic cells to survive in the hostile microenvironment of tumor in target organ.

We examined miRNA expression from RNA isolated from the frontal cortex (Broadman area 9) of 9 alcoholics (6 males, 3 females, mean age 48 years) and 9 matched controls using both the Affymetrix GeneChip miRNA 2.0 and Human Exon 1.0 ST Arrays to further characterize genetic influences in alcoholism and the effects of alcohol consumption on predicted target mRNA expression. A total of 12 human miRNAs were significantly up-regulated in alcohol dependent subjects (fold change ≥1.5, false discovery rate (FDR) ≤0.3; p

Ceramides are poorly characterized in human adipose tissue. The aim of this study was to investigate concentrations of different ceramide species in human subcutaneous and visceral adipose tissue depots and to determine associations between ceramides and global gene expression profiles.Concentrations of six ceramide species were determined in plasma and in subcutaneous and mediastinal adipose tissue from 10 overweight subjects (BMI 29.4 ± 4.9 kg/m(2)). In the adipose tissue biopsies gene expression arrays were performed and relationships between ceramides and gene expression analyzed. Immunostaining of the two adipose tissue depots was performed in an independent group of 10 patients. Mediastinal adipose tissue contained significantly higher concentrations (p0.05) of all six ceramide species than the subcutaneous depot. Of the six ceramides in plasma, concentrations of only two (Cer d18:1/18:0 and Cer d18:1/22:0) correlated significantly (p0.05) with the corresponding species in mediastinal adipose tissue, but there were no significant correlations between ceramides in plasma and subcutaneous adipose tissue. Multivariate analysis identified significant correlations between the total ceramide concentration and global gene expression within mediastinal, but not subcutaneous adipose tissue, according to cross-validation. Gene ontology analysis of genes related to ceramides in the mediastinal depot revealed that genes positively correlated with ceramides were associated mainly with immune and inflammatory categories, while genes negatively correlated with ceramides were associated mainly with lipid and carbohydrate metabolism.Ceramides in human mediastinal adipose tissue may be involved in inflammation and lipid and carbohydrate metabolism.

Beside their structural role for the cell membrane the family of sphingolipids act as effector molecules in signal transduction with links to various aspects of cancer initiation, progression and treatment response. The “sphingolipid rheostat” balances between apoptosis inducing ceramid and growth promoting sphingosine-1-phosphate. We analyzed gene expression of 43 proteins from this pathway in different subtypes of breast cancer using microarray data of 1,269 tumor samples (test set n = 171; validation sets n = 1098) and observed significant differences for several genes. Sphingosine kinase 1 (SPHK1), ceramide galactosyltransferase (UGT8), and Ganglioside GD3-Synthase (ST8SIA1) displayed higher expression among ER negative tumors. In contrast, glucosylceramidsynthase (GCS), dihydroceramidsynthases (LASS4, LASS 6) and acid ceramidase (ASAH1) were higher expressed in ER positive samples. Survival analysis revealed a worse outcome of patients with high SPHK1 expression. To avoid a confounding effect of the ER status we also restricted the analysis to 750 patients with ER positive tumors. Again a worse outcome was observed for tumors displaying high SPHK1 expression. While 75.8 ± 1.9% of the patients with tumors low in SPHK1 expression were free of metastasis at 5 years, this was the case for only 64.9 ± 3.6% of patients with tumors displaying high SPHK1 expression (P = 0.008). Immunohistochemistry identified the carcinoma cells as the major source of SPHK1 expression in the tumor. The correlation of SPHK1 with a poor prognosis as well as its high expression among ER negative tumors are in line with the antiapoptotic and proliferative properties of its product sphingosine-1-phosphate. Targeting of the sphingolipid rheostat may thus open new treatment options.

INTRODUCTION: Glioblastoma (GBM) is the most common malignant brain tumor in adults with a poor outcome due to recurrence from residual disease. Tumour cell invasion into brain parenchyma is likely a major contributor to multimodal treatment failure. Understanding the mechanisms that govern invasion will permit the identification of molecular targets that are functionally important for recurrence disease progression. METHOD: We analysed RNA-sequencing data consisting of tissues within the contrast-enhancing (CE) region, core (C) and non-enhancing (NE) margins of tumors from 27 GBM, and 17 normal brain (NB) samples. To identify NE-specific alterations in transcriptome organization, we conducted a genome-wide gene co-expression network analysis. RESULTS: Twenty modules of co-expressed genes were identified and revealed that expression patterns of NE are more similar to NB than CE for the majority of the modules. Two discrete modules (M1 and M2) were significantly associated with NE and are highly enriched with oligodendocyte (M1: 13 genes, FDR < 3.11 × 10–09; M2: 36 genes, FDR < 2.63 × 10–32) and white matter-associated (M1: 8 genes, FDR < 1.16 × 10–09; M2: 10 genes, FDR < 1.01 × 10–05) genes. M1 was enriched for integrin mediated signalling (DOCK1, FUT8, GAB2), vacuole organization (MAN2A1, PSEN1, TFEB), and platelet activation (RHOG, TGFB3). In contrast, M2 was enriched for lipid biosynthetic processes (GPAT2, GPD1, PIP4K2A, UGT8), ion transport (BEST1, SGK2, SGK3, TMC6), and cell shape regulation (ERMN, FGD4, S100B, SEMA4D). CONCLUSION: Unique molecular GBM abnormalities i implicate transcriptional dysregulation of distinct biological processes that are associated with invasion.

Abstract #6014 Backround: Sphingolipids do not only have structural roles for the cell membrane, but also act as effector molecules and second messengers in signal transduction with links to cancer initiation, progression and treatment response. Knowledge of sphingolipid's impact on breast cancer and its prognosis is limited to in vitro data. Clinical data is rare but needed. Material and Methods: We analyzed gene expression of 43 proteins from the sphingolipid pathways in different subtypes of breast cancer using microarray data of 1269 tumor samples (test set n=171; validation sets n=1098). Kaplan Meier analysis of disease free survival was performed to examine the prognostic value of different markers. In addition immunohistochemistry was done to determine whether the genes of the sphingolipid rheostat are expressed in cancer or stroma cells of the tumor. Results: Significant relationships of several genes of the sphingolipid metabolism with clinical parameters were obtained. Sphingosine kinase 1 (SPHK1), ceramide galactosyltransferase (UGT8), and Ganglioside GD3-Synthase (ST8SIA1) displayed higher expression among ER negative tumors. In contrast, glucosylceramidesynthase (GCS), dihydroceramidesynthases (LASS4, LASS 6) and acid ceramidase (ASAH1) were higher expressed in ER positive samples. Survival analysis revealed a significant worse outcome of patients with high SPHK1 expression. LASS 6 and GCS gene expression had no prognostic impact when the estrogen receptor status was taken into account in multivariate analyses. Immunohistochemistry identified the carcinoma cells as the major source of SPHK1 expression in the tumor. Conclusions: These studies of a large cohort of clinical breast cancer samples reveal that sphingolipids do play a role in breast cancer. Enzymes of the sphingolipid metabolism have impact on the prognosis of breast cancer patients and targeting the sphingolipid rheostat can open new treatment options. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6014.