Expression and role of the cell surface protease seprase/fibroblast activation protein-α (FAP-α) in astroglial tumors

Abstract Seprase or fibroblast activation protein-α (FAP-α) is a cell-surface serine protease that was previously described nearly exclusively on reactive and tumor stromal fibroblasts and thought to be involved in tissue remodeling. We investigated the expression and significance of FAP-α in astrocytomas/glioblastomas. As shown by quantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohisto-chemistry, FAP-α was elevated in whole glioblastoma tissues and in particular in most glioma cells in situ and in vitro. In glioma stem-like cells (gliospheres), FAP-α was detected at low levels; however, FAP-α was considerably induced upon differentiation with 10% fetal calf serum. To explore its functional role, FAP-α was silenced by siRNA transfection. In Boyden chamber assays, FAP-α silenced cells migrated similar as control cells through non-coated or Matrigel (basal lamina)-coated porous membranes, but significantly slower through membranes coated with gelatin or brevican, a major component of brain extracellular matrix. Furthermore, FAP-α-silenced glioma cells migrated through murine brain slices much slower under the conditions tested than differentially fluorescent-labeled control cells. Thus, FAP-α is highly expressed on the surface of glioma cells and contributes to diffuse glioma invasion through extracellular matrix components.

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Lactobacillus Cell Surface Proteins Involved in Interaction with Mucus and Extracellular Matrix Components

Current Microbiology ◽

10.1007/s00284-020-02243-5 ◽

2020 ◽

Vol 77 (12) ◽

pp. 3831-3841

Author(s):

Lidia Muscariello ◽

Barbara De Siena ◽

Rosangela Marasco

Keyword(s):

Extracellular Matrix ◽

Cell Surface ◽

Intestinal Flora ◽

Surface Proteins ◽

Matrix Proteins ◽

Cell Surface Proteins ◽

Host Interaction ◽

Extracellular Matrix Components ◽

Probiotic Strains ◽

Matrix Components

AbstractThe gut microbiota is a complex microbial ecosystem where bacteria, through mutual interactions, cooperate in maintaining of wellbeing and health. Lactobacilli are among the most important constituents of human and animal intestinal microbiota and include many probiotic strains. Their presence ensures protection from invasion of pathogens, as well as stimulation of the immune system and protection of the intestinal flora, often exerted through the ability to interact with mucus and extracellular matrix components. The main factors responsible for mediating adhesion of pathogens and commensals to the gut are cell surface proteins that recognize host targets, as mucus layer and extracellular matrix proteins. In the last years, several adhesins have been reported to be involved in lactobacilli–host interaction often miming the same mechanism used by pathogens.

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P11.41 Comparison of fibroblast activation protein expression and localization in glioblastomas and brain metastases

Neuro-Oncology ◽

10.1093/neuonc/noz126.187 ◽

2019 ◽

Vol 21 (Supplement_3) ◽

pp. iii52-iii52

Author(s):

P Busek ◽

M Zubal ◽

B Chmielova ◽

Z Vanickova ◽

P Hrabal ◽

...

Keyword(s):

Tumor Microenvironment ◽

Brain Metastases ◽

Cancer Cells ◽

Brain Tissue ◽

Mesenchymal Stromal Cells ◽

Stromal Cells ◽

Glioma Cells ◽

Fibroblast Activation Protein ◽

Epithelial Cancer ◽

Fibroblast Activation

Abstract BACKGROUND Fibroblast activation protein (FAP) is a transmembrane serine protease that is frequently upregulated in the tumor microenvironment. In several cases, FAP protein itself and/or FAP expressing stromal cells have been shown to contribute to cancer progression and to be associated with more aggressive cancer behaviour and shorter patient survival. The aim of this study was to determine FAP expression in glioblastomas and brain metastases and to identify the cell types that express FAP in the microenvironment of these malignancies. MATERIAL AND METHODS FAP enzymatic activity and protein concentration were determined in samples from patients with brain metastases, glioblastomas and pharmacoresistant epilepsy (control non-tumorous brain tissue) by an enzymatic assay using a specific fluorogenic substrate and ELISA, respectively. Immunohistochemical labelling with antibodies against FAP and markers of astroglia, epithelial cancer cells and mesenchymal stromal cells was performed to characterize FAP expressing cells. RESULTS FAP was significantly upregulated in the majority of glioblastomas and brain metastases in comparison to non-tumorous brain tissue. In glioblastomas, FAP was localized perivascularly and in mesenchymal cells, and in part of the tumors also in the glioma cells. In brain metastases, FAP positivity was abundantly present in the stroma and predominantly co-localised with markers of mesenchymal stromal cells (TE-7, SMA, PDGFRbeta, NG2), but there was no overlap between FAP and markers of epithelial cancer cells (EpCAM, pancytokeratin). CONCLUSION FAP is upregulated in the microenvironment of human glioblastomas and brain metastases compared to non-tumorous brain tissue. In glioblastomas, FAP is expressed in part of the glioma cells, in pericytes and mesenchymal stromal cells, whereas no positivity in cancer cells and more abundant FAP+ stroma was detected in brain metastases. The selective expression of FAP in these brain tumors may be useful for the visualization and possibly therapeutic targeting of their tumor microenvironment. GRANT SUPPORT Ministry of Health of the Czech Republic, grant No. 15-31379A, Progres Q28/LF1, 2015064 LM EATRIS and the project,Center for Tumor Ecology - Research of the Cancer Microenvironment Supporting Cancer Growth and Spread” (reg. n. CZ.02.1.01/0.0/0.0/16_019/0000785) supported by the Operational Programme Research, Development and Education.

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Fibroblast activation protein: A cell surface dipeptidyl peptidase and gelatinase expressed by stellate cells at the tissue remodelling interface in human cirrhosis

Hepatology ◽

10.1002/hep.510290631 ◽

1999 ◽

Vol 29 (6) ◽

pp. 1768-1778 ◽

Cited By ~ 179

Author(s):

Miriam T. Levy ◽

Geoffrey W. McCaughan ◽

Catherine A. Abbott ◽

John E. Park ◽

Anne M. Cunningham ◽

...

Keyword(s):

Cell Surface ◽

Protein A ◽

Stellate Cells ◽

Dipeptidyl Peptidase ◽

Fibroblast Activation Protein ◽

Tissue Remodelling ◽

Fibroblast Activation ◽

A Cell

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Syndecan, a developmentally regulated cell surface proteoglycan that binds extracellular matrix and growth factors

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1990.0052 ◽

1990 ◽

Vol 327 (1239) ◽

pp. 171-186 ◽

Cited By ~ 148

Keyword(s):

Extracellular Matrix ◽

Growth Factor ◽

Cell Surface ◽

Cell Shape ◽

Heparan Sulphate ◽

Tissue Type ◽

Cell Behaviour ◽

Extracellular Matrix Components ◽

Cellular Behaviour ◽

Cell Surface Proteoglycan

Cellular behaviour during development is dictated, in part, by the insoluble extracellular matrix and the soluble growth factor peptides, the major molecules responsible for integrating cells into morphologically and functionally defined groups. These extracellular molecules influence cellular behaviour by binding at the cell surface to specific receptors that transduce intracellular signals in various ways not yet fully clear. Syndecan, a cell surface proteoglycan found predominantly on epithelia in mature tissues binds both extracellular matrix components (fibronectin, collagens I, III, V, and thrombospondin) and basic fibroblast growth factor (bFGF). Syndecan consists of chondroitin sulfate and heparan sulphate chains linked to a 31 kilodalton (kDa) integral membrane protein. Syndecan represents a family of integral membrane proteoglycans that differ in extracellular domains, but share cytoplasmic domains. Syndecan behaves as a matrix receptor: it binds selectively to components of the extracellular matrix, associates intracellularly with the actin cytoskeleton when cross-linked at the cell surface, its extracellular domain is shed upon cell rounding and it localizes solely to basolateral surfaces of simple epithelia. Mammary epithelial cells made syndecan-deficient become fibroblastic in morphology and cell behaviour, showing that syndecan maintains epithelial cell morphology. Syndecan changes in quantity, location and structure during development: it appears initially on four-cell embryos (prior to its known matrix ligands), becomes restricted in the pre-implementation embryo to the cells that will form the embryo proper, changes its expression due to epithelial-mesenchymal interactions (for example, induced in kidney mesenchyme by the ureteric bud), and with association of cells with extracellular matrix (for example, during B-cell differentiation), and ultimately, in mature tissues becomes restricted to epithelial tissues. The number and size of its glycosaminoglycan chains vary with changes in cell shape and organization yielding tissue type-specific polymorphic forms of syndecan. Its interactions with the major extracellular effector molecules that influence cell behaviour, its role in maintaining cell shape and its spatial and temporal changes in expression during development indicate that syndecan is involved in morphogenesis.

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The stromal cell-surface protease fibroblast activation protein-α localizes to lipid rafts and is recruited to invadopodia

Biochimica et Biophysica Acta (BBA) - Molecular Cell Research ◽

10.1016/j.bbamcr.2015.07.013 ◽

2015 ◽

Vol 1853 (10) ◽

pp. 2515-2525 ◽

Cited By ~ 9

Author(s):

Julia D. Knopf ◽

Stefan Tholen ◽

Maria M. Koczorowska ◽

Olivier De Wever ◽

Martin L. Biniossek ◽

...

Keyword(s):

Cell Surface ◽

Lipid Rafts ◽

Stromal Cell ◽

Fibroblast Activation Protein ◽

Fibroblast Activation ◽

Cell Surface Protease

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Extracellular matrix and breast cancer cells' response to trastuzumab: The role of glycosaminoglycans, heparanases, and syndecan-1.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.10568 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. 10568-10568

Author(s):

Maria Aparecida Silva Pinhal ◽

Eloah Rabello Suarez ◽

Helena Bonciani Nader ◽

Auro Del Giglio

Keyword(s):

Breast Cancer ◽

Extracellular Matrix ◽

Cell Surface ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Antibody Activity ◽

Trastuzumab Resistance ◽

Mcf7 Cells ◽

Her2 Positive ◽

Extracellular Matrix Components

10568 Background: Trastuzumab is an antibody anti-epidermal growth factor 2 receptor (HER2), which improves disease-free and overall survival in HER2 positive breast cancer. Nevertheless, many patients become resistant to this treatment. Heparanase (HPSE) is an enzyme that is responsible for removal of heparan sulfate (HS) chains from proteoglycans, generating free oligosaccharides that modulate many physiopathological functions, including tumor developing. We have analyzed whether some extracellular matrix components influence trastuzumab efficacy. Methods: Heparanase-1 (HPSE-1) overexpression effect was analyzed using MCF7 cells stable transfected with HPSE-1 cDNA (MCF7-HPSE-1). HPSE-1, HPSE-2, Syndecan-1 (Syn-1) and HER2 expression, HPSE-1 activity and cell viability were evaluated in different breast cancer cells treated or not with trastuzumab. The glycosaminoglycans synthesis and shedding were also evaluated. Trastuzumab and HS binding were analyzed by confocal microscopy and Fluorescence Resonance Energy Transfer (FRET). Results: MCF7 transfected with HPSE-1 cDNA becomes completely resistant to trastuzumab. HS affinity by Trastuzumab was then tested, showing that they bind in high levels and this binding is necessary to antibody activity. In MCF7 cells, trastuzumab decreases HPSE-1, HPSE-2, HER2 and Syn-1 mRNA expression, while in MCF7-HPSE-1 the antibody increases the expression of these molecules. Conclusions: Our results have demonstrated that an ideal concentration of HS in cell surface, regulated by trastuzumab, is necessary to its action, beyond HER2 high levels. High HS concentration at cell surface enhances the antibody amount disposable to interact with HER2 in cell surface, determining breast cancer cells susceptibility to trastuzumab. These new insights could be useful when devising strategies for overcoming trastuzumab resistance in HER2 positive cancers. Supported by FAPESP, CNPq, CAPES.

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Inhibitors of Fibroblast Activation Protein (FAP) Inhibit Primary Myeloma Growth and Osteoclastogenesis Ex Vivo and In Vivo.

Blood ◽

10.1182/blood.v110.11.813.813 ◽

2007 ◽

Vol 110 (11) ◽

pp. 813-813

Author(s):

Angela Pennisi ◽

Xin Li ◽

Dana Gaddy ◽

Nisreen Akel ◽

Nazneen Aziz ◽

...

Keyword(s):

Cell Growth ◽

Cell Surface ◽

Cell Survival ◽

Dipeptidyl Peptidase ◽

Fibroblast Activation Protein ◽

Peptidase Activity ◽

Dependent Manner ◽

Pretreatment Level ◽

Fibroblast Activation

Abstract Fibroblast activation protein (FAP), a cell surface serine protease with both dipeptidyl peptidase and collagenase activity, is selectively expressed by tumor stroma and involved in tumor metastasis. We have reported that FAP is upregulated in myelomatous bone and is overexpressed in osteoclasts after coculture with myeloma (MM) cells. FAP is not expressed by MM cells and FAP siRNA reduced MM cell survival in cocultures (Ge et al., BJH 2006). The aim of the study was to investigate the effect of FAP inhibitors, PT-100 and PT-630 on MM cell growth and osteoclastogenesis using coculture system and the SCID-hu model for primary MM. PT-630 inhibits cell surface dipeptidyl peptidase activity while PT-100 also inhibits intracellular activity of these enzymes. MM cells from 6 patients were cocultured with osteoclasts and treated twice a day with PT-100 and PT-630 (0.1–100 μM) for 5–7 days. Whereas PT-100 effectively inhibited MM cell growth in all tested doses by 38%–62% (p<0.002 vs. 100 μM), PT-630 inhibited MM cell growth in a dose dependent manner reaching 45% growth inhibition with 100 μM (p<0.02). These compounds had no direct effect on MM cell survival. Moreover, recombinant FAP had no impact on MM cells cultured alone, suggesting that FAP-induced MM cell survival depends on close contact between MM cells and osteoclasts. The anti-MM effect of PT-100 in cocultures was mediated through downregulation of phosphorylated p38 in MM cells as detected by Phospho MAPK array and confirmed by Western blot. MMP-2 and MMP-9 have been associated with FAP activity. The level of MMP-2 but not MMP-9 was reduced in coculture conditioned media by 44±7% (p<0.04) following treatment with PT-100 while PT-630 had no significant effect on production of these matrix metalloproteinases. To test effect on osteoclastogenesis, osteoclast precursors were incubated with RANKL and M-CSF in the absence and presence of PT-100 (1 μM) and PT-630 (10 μM) for 5–7 days. PT-100 and PT-630 inhibited formation of multinucleated osteoclasts by 78±6% (p<0.001) and 56±6% (p<0.003), respectively. Culture of osteoclasts on dentine slices in the presence of PT-100 and PT-630 reduced resorption pit area by 92% (p<0.01) and 69% (p<0.04), respectively. The anti-osteoclastogenic effects were mediated through inhibition of phosphorylated p38 MAPK in osteoclastic cultures in a dose related manner. In vivo, SCID-hu mice engrafted with MM cells from 4 patients were orally treated for 4–5 weeks with PT-100 (20 mg/day) and PT-630 (200 mg/day). These agents inhibited MM growth in 2 experiments, delayed growth in one experiment and had no effect on MM in an additional experiment. Overall, final hIg levels in hosts treated with vehicle, PT-100 and PT-630 were 355±170, 183±78 and 76±27 mg/ml, respectively. Bone mineral density (BMD) of the myelomatous bone was increased in responding hosts (3% vs. -32% change from pretreatment level in control) and had reduced severity of bone loss in myelomatous bone of nonresponding hosts (−15% vs. −28% change from pretreatment level in control), suggesting that, as shown in vitro, these agents directly affect bone cell function in vivo. We conclude that FAP is critically involved in MM osteolysis and tumor growth and thus approaches to inhibit FAP activity in myelomatous bone may help control MM and its associated bone disease.

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