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Query: UNIPROT:P15088 (
mast cell
)
14,925
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Plutonium-239 or 241Am administered intravenously in the monomeric citrate form was initially deposited in beagle livers principally in the hepatocytes and to a much lesser extent in the sinusoidal macrophages and connective tissues. The initial distribution was quite uniform throughout the hepatic parenchyma; however, at later postinjection intervals, depending on the amount of injected activity, the liver burden became increasingly more focal due to: (1) a progressive shift of the radionuclide from the hepatic epithelium to the macrophages; (2) the movement of such macrophages toward the portal or central regions of the lobule; and (3) the displacement of the older more radioactive tissue by regenerating hepatocytes, which generally have a much lower radionuclide content. The hepatic lesions produced by Pu or Am included: (1) necrosis and degenerative changes that were clinically serious or fatal in some of the animals injected with approximately 107 kBq kg-1; (2) marked structural and circulatory changes resulting from necrosis and focal hepatocyte hyperplasia; (3) a significant incidence of both benign and malignant primary liver tumors. In both Pu- and Am-treated dogs, the most frequently appearing neoplasm was the bile duct adenoma, followed by the cholangiocarcinoma. The most obvious difference between Pu- and Am-induced liver neoplasia was the greater frequency of fibrosarcomas and
mast cell
sarcomas in the Am-treated groups. Hepatomas were of relatively low frequency in animals with Pu or Am burdens. Although the incidence of bone neoplasia was high among the dogs in these studies, the risk of liver tumors, especially in the Am-treated animals, exceeded that of the skeleton in some of the lower dosage levels where the survival times were long. A risk coefficient of approximately 1200 fatal liver
malignancies
(10(4) beagle Gy)-1, derived from the dosage groups with long survival times, was calculated for combined Pu and Am animals. The prominence of the liver syndromes in beagles with burdens of Pu or Am indicates that humans with body burdens of 239Pu, 241Am, or other actinide elements may be at risk from radiation effects in the liver, including neoplasia development.
...
PMID:Plutonium- or americium-induced liver tumors and lesions in beagles. 188 23
Mast cell density, distribution, and ultrastructure were studied by light and electron microscopy in hamster buccal pouches undergoing chemically induced carcinogenesis. Epidermoid carcinomas in the pouches were induced by three topical applications per week of 0.5% 7,12-dimethylbenz[a]anthracene (DMBA) in oil using a brush. Four experimental, DMBA-treated and two normal, untreated hamsters were sacrificed after 8, 10, 12, 14, and 16 weeks. After 8 weeks of DMBA treatment, the epithelium showed the pathological signs of dysplasia and hyperkeratosis. In the dermis an increased number of mast cells were evident, some of which showed degranulation. A few mast cells had started to migrate upwards towards the dysplastic epithelium after 10 weeks of DMBA treatment. Rapid degranulation was also apparent in some mast cells. These processes of upward migration and degranulation continued progressively during the 12- and 14-week periods of DMBA application in correlation with the progression of the tumor. By 16 weeks of treatment with the carcinogen, more mast cells had migrated closer to the invasive carcinoma, and many had degranulated. In the connective tissue mast cells were fully packed with many granules, and some mast cells were in proximity to macrophages and eosinophils. Our observations demonstrate that there is a positive correlation between developing carcinomas and
mast cell
density. Mast cell migration towards the carcinoma and degranulation were also evident.
J
Cancer
Res Clin Oncol 1991
PMID:Sequential mast cell infiltration and degranulation during experimental carcinogenesis. 190 Oct 64
We evaluated four canine cutaneous
mast cell
tumors cytogenetically. All four tumors contained both hypodiploid and hyperdiploid cells, an increase in the number of metacentric chromosomes, exchange configurations, and cells showing loss of an X chromosome. All tumors contained metaphases with chromosome gaps and breaks at frequencies greater than observed spontaneous chromosome breaks in normal cultured canine peripheral blood lymphocytes. Three of the four tumors had a normal modal chromosome number of 78. The fourth tumor had a modal chromosome number of 93, which represented 15% of the cells evaluated from this tumor.
Cancer
Genet Cytogenet 1991 May
PMID:Cytogenetic evaluation of four canine mast cell tumors. 203 34
Infection of the bone marrow-derived
mast cell
line PB-3c with a retrovirus carrying oncogenic c-Ha-ras or v-Ha-ras reduced the interleukin 3 (IL-3) growth requirement and induced a state of tumorigenicity. In contrast, normal c-Ha-ras had no effect on the IL-3 requirement of this cell line nor did the cells become tumorigenic. A factor reduction similar to that caused by activated Ha-ras was transiently obtained with 12-O-tetradecanoylphorbol-13-acetate in the PB-3c cells expressing normal c-Ha-ras. The analogous stimulation of protein kinase C (PKC) in PB-3c cells producing oncogenic Ha-ras led to an additional reduction of the IL-3 requirement during the first 24 h. In the absence of IL-3, the prolonged exposure of the cells to 12-O-tetradecanoylphorbol-13-acetate for 72 h resulted in a stimulation of growth when activated but not when normal Ha-ras was expressed. PB-3c cell lines expressing activated Ha-ras neither revealed differences in the amounts nor in the subcellular distribution of PKC activity but displayed elevated levels of immunoreactive beta-PKC compared to the parental PB-3c cells. Upon 12-O-tetradecanoylphorbol-13-acetate treatment, a protracted down-regulation of the immunodetectable alpha-PKC as well as constitutively high levels of c-fos mRNA were observed when oncogenic Ha-ras was expressed. These data suggest the involvement of specific PKC subtypes and of c-fos in the reduction of the IL-3 requirement caused by activated Ha-ras in this particular hematopoietic cell line.
Cancer
Res 1991 Jan 15
PMID:Tumor-promoting phorbol ester and activated Ha-ras synergistically reduce the interleukin 3 requirement in a mast cell line. 198 80
Individuals with systemic
mast cell
disease (SMCD) may develop various hematologic abnormalities, including cytopenias, myeloproliferative or myelodysplastic syndromes, lymphoproliferative syndromes, and primary or secondary leukemias. Management of those patients is often complicated by their associated hematologic abnormalities. In the case of non-malignant hematologic syndromes, the approach to management is supportive. At present, overt
malignancies
are managed with traditional chemotherapy. The presence of leukemia in patients with
mast cell
disease usually indicates a grave prognosis.
...
PMID:Hematologic aspects of mastocytosis: II: management of hematologic disorders in association with systemic mast cell disease. 200 65
Mast cells were shown to accumulate around the periphery of the invasive and metastatic rat mammary adenocarcinoma (MTLn3), and histological evidence of
mast cell
degranulation was observed during the later stages of this model. To assess the physiological role of mast cells in vivo we have used the
mast cell
-stabilising compound FPL 55618 applied i.p. daily at 1 mg kg-1 for 23 days. Using groups of 12 rats we have found that this compound inhibited tumour growth at the primary site by as much as 70% in most of the treated animals compared with the control group which received equivalent volumes of saline. When the drug treatment was stopped after 23 days, tumour growth of the test group accelerated over the next 7 days and reached a similar tumour size to that of control animals. Histological studies of the tumour and contiguous host tissue at day 24 of the experiment revealed numerous extra-tumoural mast cells often showing signs of degranulation at several sites around the tumour periphery in the control animals. Such observations were not seen in those animals receiving FPL 55618 where, in contrast to controls, numerous intact mast cells were often seen within the tumour mass. Following cessation of the MC-stabilising treatment progressive
mast cell
activation was evident within 2-4 days, primarily at the tumour periphery. In vitro studies have shown that drug concentrations equivalent to five times the in vivo dose had no effect on the proliferative rate or viability of the MTLn3 cells. Moreover, the proliferative rate of these cells in culture was significantly increased when exposed to soluble
mast cell
products. Thus our data indicate that a
mast cell
-stabilising compound has significant benefits in reducing tumour growth in vivo, an observation which supports the concept that
mast cell
:tumour cell interactions are important for the growth and invasive properties demonstrated by this model of breast carcinoma.
Br J
Cancer
1991 Jun
PMID:Mast cell modulation of tumour cell proliferation in rat mammary adenocarcinoma 13762NF. 206 44
Appreciable yields of cutaneous
mast cell
tumors were induced in a two-stage skin carcinogenesis protocol comprising N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) initiation followed by 12-O-tetradecanoylphorbol-13-acetate (TPA) promotion in 4 of 5 strains of mice. Only female mice of each of the 5 strains were studied. The incidences of benign and/or malignant lesions differed considerably between strains; 27% in DBA/2, 22% in BDF1, 11% in BALB/c, 10% in CDF1 and 0% in C57BL/6 mice and no
mast cell
tumors were detected in any of the strains when treated with the initiator alone. First found in a DBA/2 mouse at week 50, most tumors were observed after 100 weeks of promotion, and were usually small in size (less than 2 mm in diameter) and predominantly located within the corium, although they occasionally extended into the subcutaneous tissue. Histologically, the benign
mast cell
tumors were composed of non-encapsulated, well circumscribed densely packed sheets of discrete cuboidal or rhomboid cells. Metachromatic granules were clearly visible in the cytoplasm by Toluidine Blue staining. Two of the tumors induced in DBA/2 mice were diagnosed as malignant
mast cell
tumors on the twin bases of cellular atypia and deep infiltration into the muscular layer. The cutaneous
mast cell
tumors were constantly accompanied by subepidermal
mast cell
aggregations which were also commonly observed in tumor-free skin of mice receiving the initiation-promotion procedure.
Cancer
Lett 1990 Jan
PMID:Induction of cutaneous mast cell tumors by N-methyl-N'-nitro-N-nitrosoguanidine followed by TPA in female mice of 4 out of 5 strains tested. 210 34
We describe a patient with fever and multiple osteolytic bone lesions accompanied by hypercalcemia, a duodenal ulcer, anemia, and thrombocytopenia. Bone marrow showed a dense infiltration by abnormal cells characterized by small basophil granula, erythrophagocytosis and nuclear atypia. These cells were positive for toluidine blue and partly for myeloperoxidase and chloroacetate esterase, expressed myeloid differentiation markers, and exhibited multiple numerical and structural chromosome aberrations. Molecular genetic analysis showed no breakpoint cluster region rearrangement. Electron microscopy demonstrated granula both of basophil and
mast cell
type. Concluding, in this patient an acute hematopoietic
malignancy
with many features of malignant mastocytosis but also with signs of a basophil differentiation. This is further support for a hematopoietic stem cell origin of human mast cells.
...
PMID:Philadelphia chromosome-negative acute hematopoietic malignancy: ultrastructural, cytochemical and immunocytochemical evidence of mast cell and basophil differentiation. 210 68
Rodent and human tumor cell lines secrete a potent vascular permeability factor (VPF) which causes a rapid and substantial increase in microvascular permeability to plasma proteins without causing
mast cell
degranulation, or endothelial cell damage or without exciting an inflammatory cell infiltrate [D. R. Senger, S. J. Galli, A. M. Dvorak, C. A. Perruzzi, V. S. Harvey, and H. F. Dvorak. Science (Wash. DC), 219: 983-985, 1983; D. R. Senger, C. A. Perruzzi, J. Feder, and H.F. Dvorak.
Cancer
Res., 46: 5629-5632, 1986]. VPF now has been purified to homogeneity from guinea pig tumor cell culture medium; it is a Mr 34,000-43,000 protein, and a NH2-terminal amino acid sequence has been derived. A synthetic peptide corresponding to amino acid residues 1-24 of the native protein was used to raise rabbit antibodies which bind all of the vessel permeability-increasing activity secreted by guinea pig tumor cells and which stain purified VPF on immunoblots. These findings establish that this NH2-terminal amino acid sequence was derived from the permeability factor. Homology searches found no identity or close similarity between VPF NH2-terminal sequence and database sequences, indicating that VPF is distinct from other proteins for which sequence data are available. In particular, no sequence similarity was found between tumor-secreted VPF and other mediators of increased vessel permeability including plasma and glandular kallikreins.
Cancer
Res 1990 Mar 15
PMID:Purification and NH2-terminal amino acid sequence of guinea pig tumor-secreted vascular permeability factor. 215 59
Tumour necrosis factor-alpha (TNF-alpha)/cachectin is a multifunctional cytokine that has effects in inflammation, sepsis, lipid and protein metabolism, haematopoiesis, angiogenesis and host resistance to parasites and
malignancy
. TNF-alpha was first described in activated macrophages, but certain mouse or rat
mast cell
populations (reviewed in refs 4,5) and some in vitro-derived human cells with cytochemical features of mast cells-basophils may also contain products similar to TNF-alpha. Here we present evidence that resident mouse peritoneal mast cells constitutively contain large amounts of TNF-alpha bioactivity, whereas cultured, immature mast cells vary in their TNF-alpha content. IgE-dependent activation of cultured or peritoneal mast cells induces extracellular release of TNF-alpha and augments levels of TNF-alpha messenger RNA and bioactivity. These findings identify mouse mast cells as an important source of both preformed and immunologically inducible TNF-alpha, and suggest that release of TNF-alpha by mast cells may contribute to host defence, the pathophysiology of allergic diseases and other processes dependent on TNF-alpha.
...
PMID:Mast cells as a source of both preformed and immunologically inducible TNF-alpha/cachectin. 237 92
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