Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors analyze the ultrastructure of mast cells and perineurial cells when both are present in neurofibroma of the nerve sheath. Samples of pathologic tissue taken from three patients with neurofibroma of a peripheral nerve sheath were analyzed by light and transmission electron microscopy. The observations document the characteristics of the tumor cells (Schwann cells and perineurial cells) as well as the presence of numerous mast cells, typically in close contact with the perineurial cells and never with the Schwann cells. Many electron-dense vesicles were found between the cells; these vesicles are created when the cell membrane of the mast cell buds, and then they come into contact with the adjacent perineurial cell. Endocytosis vesicles are often present in the cytoplasm of perineurial cells. Analysis of these observations led the authors to assume the existence of a metabolic interaction between the two cell type in contact with each other and an active role of the mast cells in the evolution of the tumor. The following two theories are plausible: either the mast cells actively stimulate tumor growth, or they alter the phenotype of the tumor cell. These findings could have interesting clinical applications. The use of treatment protocols which inhibit mast cell activity could, in theory, stop either the proliferation of the neurofibroma or its malignant transformation.
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PMID:The ultrastructure of peripheral neurofibroma: the role of mast cells and their interaction with perineurial cells. 128 86

Mast cells are widely distributed in perivascular connective tissues, especially in areas of active tumor growth and vascular reactivity. Incubation of metabolically [35S]O4 = -labeled subendothelial extracellular matrix (ECM) with lysates of bone marrow-derived mouse mast cells (BMMC) resulted in extensive degradation of heparan sulfate (HS) into fragments 5 to 6 times smaller than intact HS side chains. A much lower activity (seven- to eightfold) was expressed by intact BMMC incubated in contact with the ECM. These fragments were not produced in the presence of heparin, were sensitive to deamination with nitrous acid, and resistant to further degradation with papain or chondroitinase ABC. These results indicate that an endoglycosidase (heparanase) is involved in BMMC-mediated degradation of HS in the subendothelial ECM. Heparanase activity was not detected in medium conditioned by cultured BMMC, or in lysates of Ableson transformed BMMC and rat basophilic leukemic (RBL) cells. Both heparanase and beta-hexosaminidase, a mast cell granule enzyme, were released on degranulation of BMMC induced by the calcium ionophore A23187, or by exposure to IgE-Ag, suggesting that heparanase is localized in the cell granules. Under these conditions, less than 5% of the cellular content of lactate dehydrogenase were released. Degradation of the ECM-HS by the mast cell heparanase and the associated release of HS-bound endothelial cell growth factors that are stored in ECM (Vlodavsky et al, Proc Natl Acad Sci USA 84:2292, 1987; Bashkin et al, Biochemistry 28:1737, 1989) may play a role in the proposed mast cell-mediated stimulation of neovascularization.
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PMID:Degranulating mast cells secrete an endoglycosidase that degrades heparan sulfate in subendothelial extracellular matrix. 169 99

The behavior of mast cells was studied during tumor growth. Sarcoma 13, and normal syngeneic kidney, as control, were implanted subcutaneously in BALBc mice. The number of mast cells in the hypodermis and peritumoral tissue increased 3-fold, 20 days after implantation. In the peritumoral tissue, mast cell degranulation increased together with tumor growth, while in the dermis and hypodermis, it first decreased and only became evident on day 20. Mitosis and mast cell degranulation, more conspicuous in tissues near the tumor, seem to indicate the existence of tumoral factors which spread slowly from the tumor to distant zones. The role of mast cells in peritumoral tissues will be evaluated in the near future.
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PMID:Mast cell kinetics during tumor growth. 237 97

3 patients with generalized neurofibromatosis were treated with the mast cell blocking substance Ketotifen. Pruritus and pain could be inhibited significantly and the tumor growth could be prevented.
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PMID:[Ketotifen inhibits urticaria and tumor progression in neurofibromatosis]. 251 Oct 44

The hypothesis of this study is summarized in Fig. 6. Phosphatidylserine due to distribution in the internal side of plasma membrane is prevented to react with the extracellular environment. When injury to cell occurs, phospholipid asymmetry is lost and the exposed phosphatidylserine becomes a signal of cell damage. Phosphatidylserine may activate defense reactions while it is still anchored to plasma membrane (Zwaal, 1978; Tanaka and Schroit, 1983). Alternatively, the soluble lysophosphatidylserine is generated, ready to diffuse and transmit the information of tissue damage to other cells. In this sequence of events, lysophosphatidylserine becomes an autacoid, originated from a membrane phospholipid. In rodents, lysophosphatidylserine seems specifically devoted to activate mast cells. The role of these cells in the regulation of the immune reactions and in tissue repair has been advocated (Dexter et al., 1981). The lysophosphatidylserine-induced mast cell activation has been shown in vivo and in vitro in a variety of rodent species (mouse, rat, gerbil, hamster). It may occur through a direct effect or through the participation of synergistic endogenous compounds. Structure-activity relationships in the action of lysophosphatidylserine show that the effect on mast cells is linked to a definite molecular organization. Determinants of the mast cell activation are the free amino group and the carboxyl group of the serine. Support to the general hypothesis of this study originates from the observation that active lysophosphatidylserine is generated within a population of leukocytes, the cells migrating in areas of wounded tissue (Mietto et al., 1987). Production of lysophosphatidylserine can be anticipated in pathological situations associated with extensive cell death (tumor growth, graft rejection, burns). At present, the observations on lysophosphatidylserine are confined to rodent mast cells. Other histamine-secreting cells (e.g., the human basophil) are unresponsive to this phospholipid (Kolster et al., 1987). Among the endogenous compounds interacting with lysophosphatidylserine, nerve growth factor seems of particular interest (Bruni et al., 1982). The synergism with lysophosphatidylserine has been confirmed in other laboratories (Sugiyama et al., 1985; Pearce and Thompson, 1986; Mazurek et al., 1986). The concerted effects by these two compounds on mast cells is in line with current opinion on the participation of nerve growth factor in the regulation of inflammatory and immune reactions (Mietto et al., 1987; Weskamp and Otten, 1987).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Autacoid properties of lysophosphatidylserine. 307 95

We have previously reported that rodent tumor cell lines secrete a potent vascular permeability factor with a molecular weight of 34,000-42,000 (Senger et al. Tumor cells secrete a vascular permeability factor that promotes accumulation of ascites fluid. Science (Wash. DC), 219: 983-985, 1983). This tumor-secreted vascular permeability factor (VPF) causes a rapid and completely reversible increase in microvascular permeability in the species (guinea pig or rat) from which the tumors were derived without causing mast cell degranulation or endothelial cell damage or exciting an inflammatory cell infiltrate. This VPF may be responsible, at least in part, for the increased permeability which is commonly displayed by solid and ascites tumor vessels. We have now examined 7 human tumor cell lines and have determined that 5 of them also secrete this same VPF. Antibody raised to guinea pig line 10 VPF neutralized more than 90% of the vascular permeability-increasing activity secreted by these 5 human tumor lines. Furthermore, VPFs from both guinea pig and human tumor sources bound to and were eluted similarly from immobilized heparin and comigrated identically on sodium dodecyl sulfate-polyacrylamide gels. Finally, 2 tumorigenic (in nude mice) human cell lines were found to secrete at least 14-fold more VPF than their directly matched, nontumorigenic counterparts, suggesting that elevated expression of this permeability factor may correlate with neoplastic transformation. These data suggest that a broad spectrum of tumor cells from several species, including humans, secretes a highly conserved molecule that enhances local vascular permeability and that this function may be important for tumor growth.
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PMID:A highly conserved vascular permeability factor secreted by a variety of human and rodent tumor cell lines. 375 10

The influence of mast cells on tumor incidence and growth rate was studied in 2 grafted tumor models (fibrosarcoma MC-B6-1 and the Lewis lung carcinoma 3LL). Three kinds of WBB6F1 mice (a cross between WB/ReJ-W/+ and C57BL/6J-WV/+ mice) were used: W/WV (deeply mast cell depleted), WV/+ (partially mast cell depleted), and +/+ (normal mast cell number). The presumed resistance of F1 hybrids to tumor cells of parental origin was observed in 12 of 13 +/+ mice, but only in 11 of 22 WV/+ mice and in none of 39 W/WV mice. Tumor incidence and metastasis incidence were inversely correlated with tissue histamine levels and mast cell number. Growth rates of tumors were similar in W/WV and WV/+ mice, but the tumor growth rate was much slower in the only +/+ mouse in which the tumor grew. These results confirm the protective role of mast cells against tumors.
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PMID:Inverse correlation between tumor incidence and tissue histamine levels in W/WV, WV/+, and +/+ mice. 385 69

The involvement of mast cells in anti-tumor resistance was studied by employing 2 strains of mast cell deficient but otherwise immunocompetent mice on a C57BL/6 (H-2b) background (W/Wv and Sl/Sld) and their respective normal +/+ littermate controls. Sensitization of control mice with irradiated semisyngeneic B16 melanoma cells (H-2b) resulted in protection against subsequent challenge with viable B16 cells, in contrast to sensitization of either W/Wv or Sl/Sld mice. The involvement of serotonin in antitumor resistance was studied by employing 2 serotonin active drugs: reserpine, that depletes mast cells of serotonin; and methysergide, a serotonin antagonist. Sensitization of BDF1 mice with irradiated B16 cells and sensitization of DBA/2 mice (H-2d) with irradiated SL2 cells (H-2d) resulted in protection against subsequent challenge with viable B16 cells and viable SL2 cells, respectively. Treatment with either reserpine or methysergide resulted in a decreased protection. Delayed-type hypersensitivity (DTH) footpad responses to allogeneic L5178Y (H-2d) tumor cells in C57BL/6 mice showed a biphasic reaction pattern, similar to that found in DTH responses to simple reactive haptens, such as picryl chloride. Moreover, the early swelling responses were also dependent on T cells and on mast cells. BDF1 mice carrying a semisyngeneic L5178Y tumor on the chest showed an early swelling response after footpad challenge but no late response, possibly indicating that selective down regulation of the late component of DTH was associated with progressive tumor growth in these animals. The biphasic patterns of DTH to both tumor cells and picryl chloride and the T cell and mast cell dependence of both antitumor resistance and DTH to tumor cells suggest that T cell-dependent activation of mast cells to allow entry of mononuclear leukocytes into sites of tumor growth is similar to the mechanism that occurs in DTH.
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PMID:A role for mast cells and the vasoactive amine serotonin in T cell-dependent immunity to tumors. 387 Dec 9

Fourteen dogs and 11 cats with various malignant tumors were treated daily with benzaldehyde at a dosage rate of 10 mg/kg of body weight, orally, divided into 4 doses. Clinical signs of toxicosis were not observed. A partial response (greater than 50% regression) was observed in animals with an oral squamous cell carcinoma and an oral melanoma. A minimal response (less than 50% regression) was observed in animals with a sweat gland adenocarcinoma and a mast cell sarcoma. One dog with an oral melanoma had stabilization of tumor growth for 8 weeks. Seemingly, benzaldehyde has only minimal anti-tumor activity at the dose studied.
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PMID:Anti-tumor evaluation of benzaldehyde in the dog and cat. 395 33

The relationship of mast cells to tumor growth has been debated but not elucidated. The existence of a mast cell-free animal, the W/Wv mouse, provides a model in which tumor metastasis can be studied with special reference to host tissues and their mast cell content rather than to the adhesiveness of the tumor cell itself. Both hind footpads of 30 W/Wv mice and 30 control mice (+/+) were injected with 2 X 10(5) cells of B16-F10 melanoma cells. The left paw received 1000 rads orthovoltage radiation 12 hr before tumor inoculation. Growth of tumors in both paws was recorded. Ten animals from each group were killed on Day 31 after tumor inoculation, and the remaining animals were kept until they died. Autopsy was performed in all animals, and patterns of metastasis were recorded. Results showed that (1) preinoculation radiation significantly slowed tumor growth in the left paw (P = 0.0009), and (2) lung metastases were present in 4 of 10 W/Wv mice, but in none of 10 +/+ mice killed after 31 days (P = 0.05). Overall, 17 of 25 W/Wv mice and 8 of 26 +/+ mice had lung metastases (P = 0.008).
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PMID:Growth of pulmonary metastases of B16 melanoma in mast cell-free mice. 396 6


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