Mast Cells Are Integral Components of the Tumor Microenvironment That Are Required for Plexiform Neurofibroma Progression.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 677-677
Author(s):  
Fengchun Yang ◽  
David A. Ingram ◽  
Shi Chen ◽  
Jin Yuan ◽  
Xiaohong Li ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mast Cell ◽  
Mast Cells ◽  
Tumor Microenvironment ◽  
Tumor Progression ◽  
Schwann Cells ◽  
Plexiform Neurofibroma ◽  
Hematopoietic System ◽  
Plexiform Neurofibromas

Abstract Interactions between tumorigenic cells and the microenvironment are increasingly recognized as integral to tumor progression in a range of human malignancies. However, the specific cellular mechanisms that are required to initiate these multistage processes are incompletely understood. Mutations in the NF1 tumor suppressor gene cause neurofibromatosis type 1, a pandemic autosomal dominant genetic disorder of the nervous system characterized by the development of neurofibromas. Neurofibromas are complex tumors composed of Schwann cells, fibroblasts, endothelial cells, and high concentrations of degranulating mast cells. Though neurofibromas are generally benign, plexiform neurofibromas can progress to malignancy. Genetic studies in cre/lox mice indicate that nullizygous loss of Nf1 in the tumorigenic Schwann cells (Krox20; Nf1flox/flox) is necessary, but not sufficient for neurofibroma formation when the microenvironment is wildtype. However, neurofibromas form with 100% penetrance in Krox20; Nf1flox/− mice that are heterozygous at Nf1 in all lineages of the tumor microenvironment (Science, 2002). Here, we addressed the role of the hematopoietic system in the tumor microenvironment by using adoptive transfer. Syngeneic Nf1+/− or wildtype (WT) bone marrow was transplanted into lethally irradiated Krox20;Nf1flox/flox mice. Krox20; Nf1flox/flox recipients transplanted with WT bone marrow (n=25) did not develop plexiform neurofibromas and had a normal lifespan. In contrast, Krox20; Nf1flox/flox mice transplanted with Nf1+/− bone marrow (n=25) consistently developed neurofibromas infiltrated with Nf1+/− mast cells. These mice had a 90% mortality at 14 months following transplantation. In complementary experiments, WT bone marrow was transplanted into irradiated Krox20; Nf1flox/− mice. Despite the remainder of the tumor microenvironment being heterozygous, WT bone marrow was sufficient to prevent tumor progression in Krox20; Nf1flox/− mice. To specifically assess the role of the mast cell compartment in tumor progression, Nf1+/− mice were intercrossed with two strains of naturally occurring W mutant mice that have variably diminished c-kit activity and mast cell function. Mice homozygous at the Wv locus have a greater than 90% reduction in c-kit activity, while W41/W41 mutants have approximately a 65–75% reduction in c-kit activity. Importantly, while Krox20;Nf1flox/flox mice transplanted with Nf1+/− bone marrow consistently develop plexiform neurofibromas, adoptive transfer of Nf1+/−; Wv/Wv or Nf1+/−; W41/W41 bone marrow cells into Krox20; Nf1flox/flox mice was sufficient to prevent neurofibroma formation. Collectively, these studies provide genetic evidence that the hematopoietic system and specifically mast cells are integral to plexiform neurofibroma formation in genetically engineered mice. These studies have therapeutic implications for NF1 since molecular therapies directed at the haploinsufficient hematopoietic cells, particularly the c-kit receptor tyrosine kinase, may have an important role in treating or preventing plexiform neurofibromas.

Mast Cells and Tumor Progression.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. SCI-33-SCI-33
Author(s):  
D. Wade Clapp ◽  
Fengchun Yang ◽  
David A. Ingram ◽  
Kent A. Robertson ◽  
Gary D. Hutchins ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mast Cells ◽  
Schwann Cell ◽  
Tumor Progression ◽  
Schwann Cells ◽  
Plexiform Neurofibroma ◽  
Genetically Engineered ◽  
Cell Functions ◽  
Kit Ligand ◽  
Genetically Engineered Mice

Abstract Abstract SCI-33 Interactions between tumorigenic cells and their surrounding microenvironment are critical for tumor progression yet remain incompletely understood. Germline mutations in the NF1 tumor suppressor gene cause neurofibromatosis type 1 (NF1), a common genetic disorder characterized by complex tumors called neurofibromas. Neurofibromas form in association with peripheral nerves and are composed of Schwann cells, blood vessels, fibroblasts and degranulating mast cells. Genetic studies in engineered mice indicate that biallelic loss of Nf1 is required in the tumorigenic cell of origin in the embryonic Schwann cell lineage. However, in the physiologic state, Schwann cell loss of heterozygosity is not sufficient for neurofibroma formation in a genetically engineered murine model and Nf1 haploinsufficiency in at least one additional nonneoplastic lineage is required for tumor progression. Recent studies in our group have focused on evaluating the role of bone marrow-derived cells, and particularly mast cells, in the tumor microenvironment. Previous work by our group established that human and murine Nf1 deficient Schwann cells secrete high concentrations of kit-ligand. Kit-ligand has a central role in multiple mast cell functions including chemotaxis, proliferation and degranulation. In a series of bone marrow transplantation studies, we established that Nf1 haploinsufficiency in bone marrow is sufficient to allow neurofibroma progression in the context of Schwann cell Nf1 deficiency. Further, genetic or pharmacologic attenuation of c-kit signaling diminishes neurofibroma initiation and progression. Collectively, the studies implicate mast cells as active participants in tumor formation and identify therapeutic targets for human phase 1-2 clinical trials. Disclosures Off Label Use: The drug imatinib mesylate was used to treat plexiform neurofibromas in genetically engineered mice, in a child with a plexiform neurofibroma, and it is currently being tested in a phase 2 clinical trial.

scholarly journals Role of Mast Cell-Derived Adenosine in Cancer

2019 ◽  
Vol 20 (10) ◽  
pp. 2603 ◽  
Author(s):  
Yaara Gorzalczany ◽  
Ronit Sagi-Eisenberg
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Tumor Microenvironment ◽  
Tumor Growth ◽  
Cancer Cells ◽  
Inflammatory Mediators ◽  
Adenosine Receptor ◽  
Tumor Development ◽  
A3 Adenosine Receptor

Accumulating evidence has highlighted the accumulation of mast cells (MCs) in tumors. However, their impact on tumor development remained controversial. Indeed, cumulative data indicate an enigmatic role for MCs in cancer, whereby depending on the circumstances, which still need to be resolved, MCs function to promote or restrict tumor growth. By responding to multiple stimuli MCs release multiple inflammatory mediators, that contribute to the resolution of infection and resistance to envenomation, but also have the potency to promote or inhibit malignancy. Thus, MCs seem to possess the power to define tumor projections. Given this remarkable plasticity of MC responsiveness, there is an urgent need of understanding how MCs are activated in the tumor microenvironment (TME). We have recently reported on the direct activation of MCs upon contact with cancer cells by a mechanism involving an autocrine formation of adenosine and signaling by the A3 adenosine receptor. Here we summarized the evidence on the role of adenosine signaling in cancer, in MC mediated inflammation and in the MC-cancer crosstalk.

Adoptive Transfer of Nf1+/− Bone Marrow Is Sufficient for Neurofibroma Progression in Krox20;Nf1flox/flox Mice.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3064-3064
Author(s):  
Fengchun Yang
Keyword(s):  
Bone Marrow ◽  
Mast Cells ◽  
Tumor Microenvironment ◽  
Schwann Cells ◽  
Genetic Disorder ◽  
Hematopoietic Cells ◽  
Tumor Formation ◽  
Conditional Knockout ◽  
Axial Tomography

Abstract Mutations in the NF1 tumor suppressor gene cause neurofibromatosis type 1 (NF1), a GTPase activating protein for Ras called neurofibromin. NF1 is a genetic disorder that affects approximately 250,000 individuals in the US, Europe, and Japan alone. Neurofibromas, the hallmark of NF1, are complex tumors characterized by tumorigenic Schwann cells, neoangiogenesis, fibrosis, and degranulating mast cells. Studies in experimental models have emphasized the role of inflammatory cells in altering the microenvironment and facilitating malignant outgrowth. Similarly, Parada (Science, 2002) found that nullizygosity of Nf1 in Schwann cells of conditional knockout mice (Krox20;Nf1flox/flox) was necessary but not sufficient for neurofibroma formation and haploinsufficiency of Nf1 in lineages within the tumor microenvironment was required for neurofibroma progression. We previously provided the first genetic, cellular, and biochemical evidence that haploinsufficiency of Nf1 alters Ras activity and cell fates in mast cells (JEM, 2000, 2001) and identified a mechanism underlying the recruitment of mast cells to tumorigenic Schwann cells (JCI 2003). However, it remains unclear whether Nf1 +/− bone marrow derived hematopoietic cells can directly contribute to neurofibroma formation in vivo. To address this question, Nf1+/− or wildtype (WT) EGFP+ bone marrow (BM) was adoptively transferred into lethally irradiated Krox20;Nf1flox/flox mice and cohorts were followed prospectively for tumor formation using positron emission tomography and computerized axial tomography. Mice transplanted with Nf1+/− but not WT BM developed progressive enlargement of the trigeminal nerve, dorsal root ganglia, peripheral nerves, and motor paralysis similar to Krox20;Nf1flox/− mice that are haploinsufficient at Nf1 in all lineages of the tumor microenvironment. Postmortem analysis revealed that Krox20;Nf1flox/flox mice transplanted with Nf1+/− BM had cellular neurofibromas containing Schwann cells, fibroblasts, blood vessels and mast cells, which closely resembled the cellular architecture of human neurofibromas. Mice transplanted with WT BM did not develop neurofibromas. These studies establish that recruitment of Nf1 +/− BM derived cells to the neurofibroma microenvironment is directly linked to neurofibroma formation and progression. Given our observations, therapies which prevent both the recruitment and the tumor promoting functions of Nf1 +/− hematopoietic cells in neurofibroma formation are currently being tested in vivo as pre-clinical trials.

scholarly journals The Four Distal Tyrosines Are Required for LAT-dependent Signaling in FcεRI-mediated Mast Cell Activation

2003 ◽  
Vol 198 (5) ◽  
pp. 831-843 ◽  
Author(s):  
Shin-ichiroh Saitoh ◽  
Sandra Odom ◽  
Gregorio Gomez ◽  
Connie L. Sommers ◽  
Howard A. Young ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mast Cell ◽  
Mast Cells ◽  
Phospholipase C ◽  
Cell Activation ◽  
Genetically Modified ◽  
Adaptor Protein ◽  
Retroviral Vectors ◽  
Mast Cell Activation

The linker for activation of T cells (LAT) is an adaptor protein critical for FcεRI-mediated mast cell activation. LAT is a substrate of the tyrosine kinases activated after TCR and FcεRI engagement. After phosphorylation of the cytosolic domain of LAT, multiple signaling molecules such as phospholipase C–γ1, Grb2, and Gads associate with phosphorylated LAT via their SH2 domains. The essential role of the four distal tyrosines in TCR-mediated signaling and T cell development has been demonstrated by experiments using LAT-deficient cell lines and genetically modified mice. To investigate the role of these four tyrosines of LAT in FcεRI-mediated mast cell activation, bone marrow–derived mast cells from LAT-deficient mice were infected with retroviral vectors designed to express wild-type or mutant LAT. Examination of bone marrow–derived mast cells expressing various tyrosine to phenylalanine mutants in LAT demonstrates a differential requirement for these different binding sites. In these studies, assays of biochemical pathways, degranulation, and cytokine and chemokine release were performed. Finally, the role of these tyrosines was also evaluated in vivo using genetically modified animals. Deletion of all four distal tyrosines, and in particular, loss of the primary phospholipase C–γ-binding tyrosine had a significant effect on antigen-induced histamine release.

ROCKI Regulates Growth, Maturation and Migration of Mast Cells.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2191-2191
Author(s):  
Veerendra Munugalavadla ◽  
Emily Sims ◽  
Jianjian Shi ◽  
Lei Wei ◽  
Reuben Kapur
Keyword(s):  
Bone Marrow ◽  
Mast Cell ◽  
Mast Cells ◽  
Cell Growth ◽  
Cell Activation ◽  
Critical Role ◽  
Hematopoietic Cells ◽  
Mast Cell Activation ◽  
Tyrosine Kinase Receptor

Abstract Mast cell activation plays a critical pathophysiologic role in asthma and allergy. A role for mast cell activation has also been described in multiple sclerosis, rheumatoid arthritis and coronary artery disease. In addition, these cells also play a prominent role in early phases of innate immunity to pathogenic bacteria. While several cytokines influence the growth, survival and maturation of mast cells; stem cell factor (SCF) and its interaction via the tyrosine kinase receptor, KIT is essential for normal mast cell development and function. However the intracellular signals that control mast cell growth, migration and maturation are not completely understood. In non-hematopoietic cells, Rho family GTPases are key regulators of many different biological processes including cell motility, growth, and differentiation. Cdc42, Rac and Rho are the most extensively studied members of this family. Although the role of Rac GTPases is becoming increasingly clear in mast cells and in hematopoietic cells in general, virtually nothing is known about the role of downstream effectors of Rho GTPases in these cells. RhoA and RhoC activate the serine/threonine protein kinases ROCKI and ROCKII. We show that both ROCKI and ROCKII are expressed in hematopoietic cells, including in bone marrow cells, splenocytes as well as in thymocytes. To determine the role of ROCK kinases in mast cells, we generated mice deficient in the expression of ROCKI. Here, we demonstrate that Rho-kinase ROCKI plays an essential role in regulating mast cell growth and maturation. We show that deficiency of ROCKI results in impaired maturation of bone marrow derived mast cells in response to IL-3 stimulation. Furthermore, the reduced maturation of ROCKI−/− mast cells is associated with reduced expression of KIT as well as reduced expression of the high affinity receptor for IgE at different stages of maturation (13% vs 7% at week1, 80% vs 52% at week2, and 93% vs 67% KIT/IgE receptor double positive cells at week3, n=3). KIT induced proliferation in response to SCF was also significantly reduced in ROCKI deficient mast cells, which was associated with reduced activation of MAPKinase Erk1 and Erk2. To test if the decreased growth in response to SCF was simply due to reduced KIT expression or due to cell intrinsic defects in ROCKI signaling, we isolated KIT positive WT and ROCKI−/− mast cells and measured growth in response to SCF and/or IL-3 stimulation by thymidine incorporation over a period of 24 and 48 hours. KIT positive ROCKI−/− mast cells showed reduced growth in response to SCF as well as in response to a combination of SCF and IL-3, suggesting a critical role of ROCKI in normal growth and maturation of mast cells. Since ROCK kinases also regulate migration in non-hematopoietic cells, we next examined the role of ROCKI in integrin (haptotactic) as well as in cytokine induced (chemotaxis) migration of mast cells. Mast cells deficient in ROCKI showed a 68% reduction in directional migration on fibronectin alone (64±7 [WT] vs 20±4, p<0.05) and a 31% reduction in the presence of SCF and fibronectin (181±16 [WT] vs 124±11 [ROCK1−/−], p<0.05), although no defects in SCF induced chemotaxis were observed. Taken together, our results identify ROCKI as a novel molecule that regulates growth, maturation and integrin-directed (haptotactic) migration of mast cells. Our results suggest that commercially available ROCK kinase inhibitors could prove to be useful small molecule inhibitors for treating diseases involving mast cells such as chronic inflammation and allergy.

Identification of Oncostatin M as a Novel KIT D816V-Dependent Cytokine in Neoplastic Human Mast Cells.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 213-213
Author(s):  
Gregor Hoermann ◽  
Sabine Cerny-Reiterer ◽  
Andrea Perne ◽  
Miriam Klauser ◽  
Leonhard Muellauer ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mast Cell ◽  
Mast Cells ◽  
Dominant Negative ◽  
Oncostatin M ◽  
Mitogen Activated Protein Kinase ◽  
Affect Expression ◽  
Mitogen Activated Protein ◽  
Kit D816v

Abstract Abstract 213 Systemic mastocytosis (SM) is a neoplastic disease of mast cells (MC) and their bone marrow-derived progenitors. The clinical picture in SM is variable ranging from an indolent course to highly aggressive variants with short survival time. The pathologic hallmark in SM is the multifocal dense infiltrate of MC in the bone marrow. Other typical features of SM include alterations of the bone marrow microenvironment such as increased angiogenesis and fibrosis. In a majority of patients, MC display the KIT mutation D816V which affects the activation loop at the entrance to the enzymatic pocket of the KIT kinase. As a consequence, KIT D816V exhibits constitutive tyrosine kinase activity and promotes cytokine-independent differentiation of MC. However, so far, little is known about KIT D816V-dependent expression of pathogenetically relevant molecules in neoplastic MC. Oncostatin M (OSM) is a pleiotropic cytokine of the interleukin-6 family which is produced mainly by activated T cells and monocytes. OSM has been shown to inhibit cell growth in cell lines derived from solid tumors but to stimulate proliferation of fibroblasts and endothelial cells. Recently, it has been reported that OSM produced by activated MC promotes growth of human dermal fibroblasts. Moreover, it has been suggested that OSM stimulates growth of murine bone marrow-derived mast cells in a mast cell/fibroblast coculture. However, expression of OSM in neoplastic MC or a potential pathogenetic role of OSM in SM have not been examined so far. The aim of the present study was to analyze expression of OSM in neoplastic human MC and to determine the role of KIT D816V in OSM expression. As assessed by immunohistochemistry performed on bone marrow sections of patients with SM, typical spindle-shaped neoplastic MC were found to express OSM. Serial section-staining confirmed that tryptase-positive MC co-express OSM. Expression of OSM was found in neoplastic MC in all patients investigated (n=15) and in all variants of SM (indolent SM as well as aggressive variants) with comparable staining intensities. Preincubation of anti-OSM antibody with a specific blocking peptide resulted in a negative stain. In Ba/F3 cells, doxycycline-inducible expression of KIT D816V led to a substantial upregulation of OSM mRNA and OSM protein, whereas expression of wild type KIT did not affect expression of OSM. In addition, the KIT D816V-positive HMC-1.2 mast cell line was found to express OSM at high levels, whereas the KIT D816V-negative HMC-1.1 subclone expressed only baseline levels of OSM. Correspondingly, the KIT D816V-targeting drug midostaurine (PKC412) decreased the expression of OSM in HMC-1.2 cells as well as in KIT D816V-expressing Ba/F3 cells in a dose-dependent manner. To investigate signaling pathways involved in KIT D816V-dependent expression of OSM, we applied pharmacologic inhibitors and dominant negative-acting signaling molecules. We found that KIT D816V-dependent expression of OSM is inhibited by the mitogen-activated protein-kinase/extracellular signal-regulated kinase (MEK) inhibitor, PD98059, but not by the phosphoinositide 3-kinase inhibitor, LY294002. Expression of dominant negative mutants of signal transducer and activator of transcription 5 (STAT5) did not affect expression of OSM in KIT D816V-expressing cells. In summary, our data identify OSM as a novel cytokine expressed in neoplastic MC in patients with SM and show that KIT D816V directly promotes expression of OSM through activation of the mitogen-activated protein-kinase pathway. OSM may be an important KIT D816V-dependent effector promoting angiogenesis and fibrogenesis/sclerosis in patients with SM. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Role of cytosolic phospholipase A2 in the production of lipid mediators and histamine release in mouse bone-marrow-derived mast cells

2000 ◽  
Vol 352 (2) ◽  
pp. 311-317 ◽  
Author(s):  
Noriaki NAKATANI ◽  
Naonori UOZUMI ◽  
Kazuhiko KUME ◽  
Makoto MURAKAMI ◽  
Ichiro KUDO ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mast Cell ◽  
Mast Cells ◽  
Phospholipase A2 ◽  
Lipid Mediators ◽  
Cytosolic Phospholipase A2 ◽  
Prostaglandin D2 ◽  
Wild Type ◽  
Cytosolic Phospholipase

Cytosolic phospholipase A2 (cPLA2) plays a critical role in mast-cell-related allergic responses [Uozumi, Kume, Nagase, Nakatani, Ishii, Tashiro, Komagata, Maki, Ikuta, Ouchi et al. (1997) Nature (London) 390, 618–622]. Bone-marrow-derived mast cells from mice lacking cPLA2 (cPLA-/- mice) were used in order to better define the role of cPLA2 in the maturation and degranulation of such cells. Cross-linking of high-affinity receptors for IgE (FcεRI) on cells from cPLA-/-mice led to the release of negligible amounts of arachidonic acid or its metabolites, the cysteinyl leukotrienes and prostaglandin D2, indicating an essential role for cPLA2 in the production of these allergic and pro-inflammatory lipid mediators. In addition, the histamine content of the mast cells and its release from the cells were reduced to 60%. While these results are in agreement with a reduced anaphylactic phenotype of cPLA-/- mice, the ratios of release of histamine and β-hexosaminidase were, paradoxically, significantly higher for cells from cPLA-/- mice than for those from wild-type mice. Consistently, IgE-induced calcium influx in mast cells was greater and more prolonged in cells from cPLA-/- mice than in those from wild-type mice. Thus the loss of cPLA2 not only diminishes the release of lipid mediators, but also alters degranulation. While the overall effect is still a decrease in the release of mast cell mediators, explaining the in vivo findings, the present study proposes a novel link between cPLA2 and the degranulation machinery.

Comparative analysis of the role of mast cells in murine asthma models using Kit‐sufficient mast cell‐deficient animals

Allergy ◽  
2021 ◽  
Author(s):  
Lea Pohlmeier ◽  
Sanchaita Sriwal Sonar ◽  
Hans‐Reimer Rodewald ◽  
Manfred Kopf ◽  
Luigi Tortola
Keyword(s):  
Mast Cell ◽  
Comparative Analysis ◽  
Mast Cells
Sign in / Sign up

Export Citation Format

Share Document