γ-Glutamyltranspeptidase (GGT, syn. γ-Glutamyltransferase) and dipeptidylpeptidase-IV (DPP-IV) activity participates in metabolic and growth control of normal and tumor cells by processing biologically active peptides. Here, we report on up-regulation of these enzymes in human brain gliomas determined by catalytic enzyme histochemistry and immunocytochemistry. Higher activity of GGT was found in 50%, 68% and 81% of WHO grade II, III and IV tumors, respectively. The process started at/near the microvasculature, from where it spread to the parenchyma. On average, the enzyme activity in grade II, III and IV gliomas exceeded controls 2.0, 3.0 and 3.5-fold, respectively. Up-regulation of DPP-IV-like activity also started at the microvasculature, but mainly in pericytes and mononuclear-like cells around the vessels and dispersed in the parenchyma. Marked elevation of this enzyme activity, comprising also tumor parenchyma, occurred only in grade IV glioblastomas (65% patients; 3.6 times above controls) which can, therefore, help in their differentiation from grade III gliomas. The increase of total DPP-IV-like activity also included its two enzymatic homologs, the canonical DPP-IV/CD26 and FAP-1α. The increase in GGT is supposed to be a tumor grade dependent response of microvasculature and tumor astrocytes to stress induced by tissue hypoxia and/or the metabolic aberrancies. The increase in DPP-IV-like activity in high-grade tumors can be attributed to inflammatory/scavenging processes performed by the mononuclear-like cells and, in glioblastomas, also to regressive changes in the structure and function of the microvasculature and tumor parenchyma, including astrocyte stress response. The inverse relationship between DPP-IV-like activity and Ki67 in most glioblastomas and shorter survival time of patients with low activity of this enzyme also suggest its anti-oncogenic effects.
- MeSH
- dipeptidylpeptidasa 4 biosyntéza MeSH
- dospělí MeSH
- gama-glutamyltransferasa biosyntéza MeSH
- gliom enzymologie patologie MeSH
- imunohistochemie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nádorové biomarkery analýza MeSH
- nádory mozku enzymologie patologie MeSH
- prognóza MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- stupeň nádoru MeSH
- upregulace MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Malignant gliomas exhibit abnormal expression of proteolytic enzymes that may participate in the uncontrolled cell proliferation and aberrant interactions with the brain extracellular matrix. The multifunctional membrane bound serine aminopeptidase dipeptidyl peptidase (DPP)-IV has been linked to the development and progression of several malignancies, possibly both through the enzymatic and nonenzymatic mechanisms. In this report we demonstrate the expression of DPP-IV and homologous proteases fibroblast activation protein, DPP8 and DPP9 in primary cell cultures derived from high-grade gliomas, and show that the DPP-IV-like enzymatic activity is negatively associated with their in vitro growth. More importantly, the DPP-IV positive subpopulation isolated from the primary cell cultures using immunomagnetic separation exhibited slower proliferation. Forced expression of the wild as well as the enzymatically inactive mutant DPP-IV in glioma cell lines resulted in their reduced growth, migration and adhesion in vitro, as well as suppressed glioma growth in an orthotopic xenotransplantation mouse model. Microarray analysis of glioma cells with forced DPP-IV expression revealed differential expression of several candidate genes not linked to the tumor suppressive effects of DPP-IV in previous studies. Gene set enrichment analysis of the differentially expressed genes showed overrepresentation of gene ontology terms associated with cell proliferation, cell adhesion and migration. In conclusion, our data show that DPP-IV may interfere with several aspects of the malignant phenotype of glioma cells in great part independent of its enzymatic activity.
- MeSH
- buněčná adheze MeSH
- buněčný cyklus MeSH
- dipeptidasy genetika metabolismus MeSH
- dipeptidylpeptidasa 4 genetika metabolismus MeSH
- dipeptidylpeptidasy a tripeptidylpeptidasy genetika metabolismus MeSH
- gliom enzymologie genetika MeSH
- imunomagnetická separace MeSH
- lidé MeSH
- mutace MeSH
- myši MeSH
- nádorové buňky kultivované MeSH
- pohyb buněk MeSH
- primární buněčná kultura MeSH
- proliferace buněk MeSH
- regulace genové exprese u nádorů MeSH
- signální transdukce genetika MeSH
- stanovení celkové genové exprese MeSH
- transfekce MeSH
- xenogenní modely - testy antitumorózní aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Dipeptidyl peptidase-IV (DPP-IV) and fibroblast activation protein-α (FAP) are speculated to participate in the regulation of multiple biological processes, because of their unique enzymatic activity, as well as by non-hydrolytic molecular interactions. At present, the role of DPP-IV and FAP in the development and progression of various types of tumors, including glioblastoma, is intensively studied, and their functional crosstalk is hypothesized. In this article, we describe the correlative expression of DPP-IV and FAP mRNA in primary cell cultures derived from human glioblastoma and associated expression dynamics of both molecules in astrocytoma cell lines depending on culture conditions. Although the molecular mechanisms of DPP-IV and FAP co-regulations remain unclear, uncoupled expression of transgenic DPP-IV and the endogenous FAP suggests that it occurs rather at the transcriptional than at the posttranscriptional level. Understanding of the expressional and functional coordinations of DPP-IV and FAP may help clarify the mechanisms of biological roles of both molecules in transformed astrocytic cells.
- MeSH
- buněčná diferenciace MeSH
- buněčné extrakty chemie MeSH
- buněčné kultury MeSH
- dipeptidylpeptidasa 4 genetika metabolismus MeSH
- enzymatické testy MeSH
- genetická transkripce MeSH
- lidé MeSH
- membránové proteiny genetika metabolismus MeSH
- messenger RNA genetika metabolismus MeSH
- neuroglie enzymologie metabolismus MeSH
- rekombinantní proteiny genetika metabolismus MeSH
- serinové endopeptidasy genetika metabolismus MeSH
- transformované buněčné linie MeSH
- želatinasy genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Meningiomas are tumors derived from arachnoid cap cells that represent approximately 30% of all intracranial tumors. In this study, we investigated 22 human meningiomas for the expression of dipeptidyl peptidase (DPP)-IV activity and/or structure homologs (DASH), including canonical DPP-IV/CD26, fibroblast activation protein-alpha (FAPalpha), DPP8 and DPP9. DPP-IV-like enzymatic activity, including all enzymatically-active DASH molecules, was found in all 18 benign meningiomas WHO grade I and IV atypical meningiomas WHO grade II by continuous rate fluorimetric assay in tissue homogenates and catalytic enzyme histochemistry in situ. In atypical meningiomas, this activity was significantly higher and was associated with higher cell proliferation as detected by Ki67 antigen immunohistochemistry. The expression of DPP-IV/CD26 and FAPalpha demonstrated by real-time RT-PCR and immunohistochemistry was low. As shown histochemically, it occurred most often on the surface of fibrous bundles and whorls rich in extracellular matrix. Compared to DPP-IV/CD26 and FAPalpha, the expression of DPP8 and DPP9 was higher and, in addition, it was present also in the cells inside these structures. Expression of CXCR4, the receptor of pro-proliferative chemokine stromal cell-derived factor-1alpha (SDF-1alpha), DPP-IV substrate, was found in all tumors, suggesting higher values in atypical grade II samples. This is the first report on the expression status of dipeptidyl peptidase-IV and related molecules in meningiomas. It shows that DPP8 and DPP9 prevail over canonical DPP-IV/CD26 and FAPalpha in all examined patients. In addition, the study suggests an increase of DPP-IV-like enzymatic activity in these tumors of WHO grade II.
- MeSH
- dipeptidasy genetika metabolismus MeSH
- dipeptidylpeptidasa 4 genetika metabolismus MeSH
- dipeptidylpeptidasy a tripeptidylpeptidasy genetika metabolismus MeSH
- dospělí MeSH
- exprese genu MeSH
- imunohistochemie MeSH
- izoenzymy genetika metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- membránové proteiny genetika metabolismus MeSH
- meningeální nádory enzymologie genetika patologie MeSH
- meningeom enzymologie genetika patologie MeSH
- messenger RNA analýza MeSH
- nádorové biomarkery analýza MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- senioři MeSH
- serinové endopeptidasy genetika metabolismus MeSH
- stanovení celkové genové exprese MeSH
- želatinasy genetika metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
Dipeptidyl peptidase-IV (DPP-IV) represents a unique proteolytic activity cleaving N-terminal X-Pro dipeptides. In addition to canonical DPP-IV/CD26, a number of other molecules have been discovered which exhibit DPP-IV-like enzymatic activity and various degree of structural similarity. These comprise enzymatically active fibroblast activation protein-alpha, DPP-II, DPP8, DPP9 and enzymatically inactive DPP6 and DPP10 that have been grouped as "DPP-IV activity and/or structure homologues" (DASH). Because the enzymatically active DASH can share similar sets of biologically active substrates and are frequently coexpressed within single cell or on tissue level, it is tempting to consider their participation on biological function(s) previously attributed to DPP-IV/CD26. It is speculated that disrupted expression and enzymatic activity of some DASH might corrupt the message carried by their substrates, with consequent promotion of abnormal cell behavior. Thus, modulation of activity of a particular enzyme using e.g. inhibitors, specific antibodies or modifying its expression may be an attractive therapeutic concept in cancer treatment. This review summarizes current knowledge of the expression and possible function of DPP-IV enzymatic activity bearing molecules in human brain tumors.
- MeSH
- biologické modely MeSH
- buněčná diferenciace MeSH
- chemokin CXCL12 metabolismus MeSH
- chemokiny metabolismus MeSH
- dipeptidylpeptidasa 4 metabolismus MeSH
- financování organizované MeSH
- glioblastom metabolismus MeSH
- gliom enzymologie metabolismus MeSH
- lidé MeSH
- mozek metabolismus MeSH
- nádory mozku enzymologie metabolismus MeSH
- proteasy metabolismus MeSH
- receptory CXCR4 metabolismus MeSH
- regulace genové exprese enzymů MeSH
- regulace genové exprese u nádorů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Dipeptidyl peptidase-IV (DPP-IV, CD26) is a serine protease almost ubiquitously expressed on cell surface and present in body fluids. DPP-IV has been suggested to proteolytically modify a number of biologically active peptides including substance P (SP) and the chemokine stromal cell derived factor-1alpha (SDF-1alpha, CXCL12). SP and SDF-1alpha have been implicated in the regulation of multiple biological processes and also induce responses that may be relevant for glioma progression. Both SP and SDF-1alpha are signaling through cell surface receptors and use intracellular calcium as a second messenger. The effect of DPP-IV on intracellular calcium mobilization mediated by SP and SDF-1alpha was monitored in suspension of wild type U373 and DPP-IV transfected U373DPPIV glioma cells using indicator FURA-2. Nanomolar concentrations of SP triggered a transient dose dependent increase in intracellular calcium rendering the cells refractory to repeated stimulation, while SDF-1 had no measurable effect. SP signaling in DPP-IV overexpressing U373DPPIV cells was not substantially different from that in wild type cells. However, preincubation of SP with the DPP-IV overexpressing cells lead to the loss of its signaling potential, which could be prevented with DPP-IV inhibitors. Taken together, DPP-IV may proteolytically inactivate local mediators involved in gliomagenesis.
- MeSH
- chemokin CXCL12 metabolismus MeSH
- dipeptidylpeptidasa 4 analýza farmakologie klasifikace MeSH
- financování organizované MeSH
- gliom enzymologie MeSH
- inhibitory serinových proteinas farmakologie MeSH
- lidé MeSH
- lysin analogy a deriváty farmakologie MeSH
- mifepriston farmakologie MeSH
- nádory mozku enzymologie MeSH
- oligopeptidy farmakologie MeSH
- pyrrolidiny farmakologie MeSH
- substance P metabolismus MeSH
- transfekce MeSH
- U937 buňky MeSH
- vápníková signalizace účinky léků MeSH
- Check Tag
- lidé MeSH
Alterations in dipeptidyl peptidase-IV (DPP-IV) enzymatic activity are characteristic of malignant transformation. Through its well-characterized functionality in regulating the activity of bioactive peptides by removal of the N-terminal dipeptide, DPP-IV activity may have profound effects upon metastatic potential and cell growth. Although DPP-IV/CD26 (EC 3.4.14.5) is the canonical representative of the group, a number of other proteins including DPP-7, 8, 9, and seprase/fibroblast activation protein-alpha (FAP-alpha) have been shown to have similar enzymatic activity. This study was set up to address the relative representation and enzymatic activity of plasma membrane localized DPP-IV/CD26 and FAP-alpha in human brain and astrocytic tumours. In parallel, expression of CXCR4, receptor for glioma cell growth stimulator chemokine SDF-1alpha known to be a DPP-IV substrate, was investigated. This is the first report showing that non-malignant brain tissue contains a DPP-IV-like enzymatic activity attributable mostly to DPP-8/9, while the substantial part of the activity in glioma is due to increased DPP-IV/CD26, localized in both the vascular and parenchymal compartments. DPP-IV enzymatic activity increased dramatically with tumour grade severity. A grade-related increase in CXCR4 receptor paralleled the rise in DPP-IV expression and activity. These data might support a role for DPP-IV regulation of the CXCR4-SDF-1alpha axis in glioma development.
- MeSH
- antigeny nádorové genetika metabolismus MeSH
- astrocytom enzymologie genetika patologie MeSH
- buněčná membrána metabolismus MeSH
- dipeptidylpeptidasa 4 genetika metabolismus MeSH
- dospělí MeSH
- financování organizované MeSH
- imunoenzymatické techniky MeSH
- lidé středního věku MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- nádorové biomarkery genetika metabolismus MeSH
- nádorové buňky kultivované MeSH
- nádory mozku enzymologie genetika patologie MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- receptory CXCR4 genetika metabolismus MeSH
- regulace genové exprese enzymů fyziologie MeSH
- RNA nádorová genetika metabolismus MeSH
- senioři MeSH
- serinové endopeptidasy genetika metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- srovnávací studie MeSH
- Publikační typ
- abstrakt z konference MeSH
