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)

Lymphoreticular neoplasms of the larynx are rare and comprise a heterogeneous group of tumors. A systematic survey of the literature and autoptic evaluation of the larynx in a relatively small number of patients with systemic lymphoreticular malignancies yielded the following findings: Primary tumors of the larynx must be clearly distinguished from laryngeal involvement by systemic or leukemic infiltrations. By far the most common primary hemopoietic tumors of the larynx are extramedullary plasmacytoma (about 90 cases published) and non-Hodgkin's lymphoma (NHL; about 65 cases published). Primary Hodgkin's disease, granulocytic sarcoma and mast cell sarcoma are extremely rare at this site. Plasmacytoma and NHL both preferentially involve the supraglottis. The subglottis is infrequently affected. Laryngeal plasmacytoma and NHL usually present clinically as localized stage IE and IIE tumors that exhibit no significant tendency to recur or generalize. The therapy of choice is local irradiation while chemotherapy should be reserved for recurrent or progressive disease. Prognosis is favourable in most cases of primary laryngeal plasmacytoma and NHL. Secondary involvement of the larynx by systemic lesions or leukemic infiltrations is usually associated with a very poor prognosis. The prognosis of patients with laryngeal involvement in acute or chronic myeloid leukemia is always poor. Although the histopathological diagnoses given in many case reports are often difficult to compare because of differences in terminology, there seems to be a marked preponderance of B-cell tumors of high-grade malignancy (centroblastic or immunoblastic lymphoma in the Kiel classification of NHL) that probably represents lymphomas originating from mucosa-associated lymphoid tissue (MALT).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The larynx in lymphoproliferative and myeloproliferative diseases. Part II: Laryngeal autopsy findings and discussion]. 792 29

Methotrexate (MTX), one of the earliest cancer chemotherapy agents, continues to be used extensively in the treatment of leukemia and a variety of other tumors. The efficacy of this drug results from its facile uptake by cells, rapid polyglutamylation and virtually stoichiometric inhibition of dihydrofolate reductase (DHFR), a key enzyme in cell replication. From the work of a multitude of biochemists, molecular biologists, organic chemists and pharmacologists, much is known about the mode of action of MTX and the mechanisms by which tumors exhibit inherent or acquired resistance to this drug. MTX enters cells primarily by a carrier-mediated active transport system whose principal substrate is 5-methyltetrahydrofolate, and additional glutamates are added to the gamma-position of the parent glutamate moiety. The tight binding of MTX to DHFR is defined from NMR and X-ray crystallographic studies of the enzyme and its drug or substrate complexes, supplemented by site-directed mutagenesis to confirm specific interactions. Resistance to the drug, encountered in cell culture model systems or in cancer patients, can result from an increased level of DHFR (due to gene amplification), mutant DHFR with reduced affinity for MTX, or decreased uptake or polyglutamylation of the drug. Although DHFR is an extremely well-studied enzyme, there is still some uncertainty about its kinetics, mechanism for reduction of folate, multiple forms, and activation by a diverse group of agents. Prodrug forms of MTX, e.g., MTX alpha-phenylalanine, which can be activated by carboxypeptidase A-monoclonal antibody conjugates, offer promise for improved efficacy of the drug by selective targeting to tumors. The large body of information summarized above has aided in the development of other folate antagonists, provides a paradigm for assessing the status of other cancer chemotherapeutic agents in current use, and offers a platform from which to speculate about the future of the field.
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PMID:The methotrexate story: a paradigm for development of cancer chemotherapeutic agents. 794 84

Genetic events, such as gene deletion, mutation, and amplification, are involved in the development and progression of colonic neoplasia. The importance of interactions between immune cells and neoplastic cells in influencing the pathogenesis of colon cancer is suggested by the clinical efficacy of levamisole, an immunostimulant, in the treatment of colon cancer and by the association of local lymphocytic infiltration with improved prognosis. Thus, the immune cell-neoplastic cell interaction can be viewed as being analogous to various host-parasite relationships that involve the immune system attempting to contain the intruding parasite on the one hand and the parasite attempting to escape detection and rejection on the other. This study is an attempt to gain a better understanding of such interactions by examining possible effects of a developing tumor on the immune system. Colon cancer was experimentally induced in mice to examine potential effects of carcinogenesis in the colon on local mucosal immune function in situ, using the expression of type I hypersensitivity as an index of immune function. Antigen-induced changes in net ion transport, a quantifiable correlate of type I hypersensitivity, were measured in the colon of mice following the administration of the procarcinogen 1,2-dimethylhydrazine (DMH). Segments of colon and small intestine from mice immunized by infection with Trichinella spiralis secrete ions, manifested as a rise in transmural short-circuit current, when challenged with T. spiralis antigen in Ussing chambers. Antigen-induced rise in transmural short-circuit current is mast cell dependent and occurs only in immunized mice. To determine the effects of early stages of colon carcinogenesis on this mucosal immune response, mice were immunized with T. spiralis prior to and after 6 weekly injections of DMH. Responsiveness to antigenic challenge was suppressed in the distal colon 4-6 weeks after the final injection of DMH. Although responsiveness to antigen was suppressed, the colonic epithelium remained sensitive to direct stimulation by exogenous secretagogues. Decreased antigen responsiveness observed in the distal colon was not due to generalized immune suppression by DMH, because the proximal colon and the jejunum retained their responsiveness to antigen, and immune rejection of a secondary T. spiralis infection from the small intestine was not altered. Visible tumors eventually developed 30 weeks after the final injection of DMH only in the distal portions of the colon. These results suggest that early stages of DMH-induced carcinogenesis are associated with the suppression of mucosal immune function, as measured by immune-regulated ion secretion, in the distal colon but not in the proximal colon or jejunum.(ABSTRACT TRUNCATED AT 400 WORDS)
Cancer Res 1994 Nov 15
PMID:Early stages of 1,2-dimethylhydrazine-induced colon carcinogenesis suppress immune-regulated ion transport of mouse distal colon. 795 25

Lymphoreticular neoplasms of the larynx are rare and comprise a heterogeneous group of tumors. A systematic survey of the literature and autoptic evaluation of the larynx in a relatively small number of patients with systemic lymphoreticular malignancies yielded the following findings: Primary tumors of the larynx must be clearly distinguished from laryngeal involvement by systemic or leukemic infiltrations. By far the most common primary hemopoietic tumors of the larynx are extramedullary plasmacytoma (about 90 cases published) and non-Hodgkin's lymphoma (NHL; about 65 cases published). Primary Hodgkin's disease, granulocytic sarcoma and mast cell sarcoma are extremely rare at this site. Plasmacytoma and NHL both preferentially involve the supraglottis. The subglottis is infrequently affected. Laryngeal plasmacytoma and NHL usually present clinically as localized stage IE and IIE tumors that exhibit no significant tendency to recur or generalize. The therapy of choice is local irradiation while chemotherapy should be reserved for recurrent or progressive disease. Prognosis is favorable in most cases of primary laryngeal plasmacytoma and NHL. Secondary involvement of the larynx by systemic lesions or leukemic infiltrations is usually associated with a very poor prognosis. The prognosis of patients with laryngeal involvement in acute or chronic myeloid leukemia is always poor. Although the histopathological diagnoses given in many case reports are often difficult to compare because of differences in terminology, there seems to be a marked preponderance of B-cell tumors of high-grade malignancy (centroblastic or immunoblastic lymphoma in the Kiel classification of NHL) that probably represents lymphomas originating from mucosa-associated lymphoid tissue (MALT).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The larynx in lymphoproliferative and myeloproliferative diseases. I: An overview with special reference to primary laryngeal malignant lymphomas and plasmacytomas]. 807 Oct 93

We have produced two lines of transgenic mice in which the expression of temperature-sensitive SV-40 large T antigen is targeted to bone marrow megakaryocytes via the platelet factor 4 (PF4) tissue-specific promoter. The progeny of these transgenic mice were observed for about 3 mo, and no malignancies were detected over this period of time. The offspring of these transgenic mice, 6- to 12-wk of age, served as a source of bone marrow cells, which upon in vitro cultivation at the permissive temperature yielded immortalized cell lines (MegT). At the permissive temperature, MegT cells exhibit the characteristics of early 2N and 4N megakaryocytes which include the presence of specific gene products such as PF4, glycoprotein IIb, acetylcholinesterase, and CD45 as well as the absence of molecular markers of other cell lineages such as the macrophage marker Mac-1, the T helper cell marker CD4, the mast cell marker IgE, the T cell marker CD2 or the erythroid cell marker alpha-globin. The inactivation of the oncogene by a shift of temperature from 34 degrees to 39.5 degrees C produces a reduction in the frequency of the 2N cells, in conjunction with the appearance of 8N and 16N cells, consisting of 27 and 3% of total cells, respectively. Thus, we have generated hematopoietic cell lines that are trapped in the early stages of megakaryocyte commitment, but able to undergo part of the normal program of terminal differentiation.
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PMID:Targeted expression of a conditional oncogene in hematopoietic cells of transgenic mice. 825 49

The detailed mechanisms which can explain the inherent radiosensitivity of salivary glands remain to be elucidated. Although DNA is the most plausible critical target for the lethal effects of irradiation, interactions with other constituents, such as cell membrane and neuropeptides, have been suggested to cause important physiological changes. Moreover, mast cells seem to be closely linked to radiation-induced pneumonitis. Therefore, in the present study the effects of fractionated irradiation on salivary glands have been assessed with special regard to the appearance of mast cells and its correlation with damage to gland parenchyma. Sprague-Dawley strain rats were unilaterally irradiated to the head and neck with the salivary glands within the radiation field. The irradiation was delivered once daily for 5 days to a total dose of 20, 35 and 45 Gy. The contralateral parotid and submandibular glands served as intra-animal controls and parallel analysis of glands was performed 2, 4, 10 or 180 days following the last radiation treatment. Morphological analysis revealed no obvious changes up to 10 days after the irradiation. At 180 days a radiation dose-dependent loss of gland parenchyma was seen, especially with regard to serious acinar cells in parotid gland and acinar cells and serous CGT (convoluted granular tubule) cells in the submandibular gland. These changes displayed a close correlation with a concomitant dose-dependent enhanced density of mast cells and staining for hyaluronic acid. This cell population seems to conform with the features of the connective tissue mast cell type. The parotid seems to be more sensitive to irradiation than the submandibular gland. Thus, the present results further strengthen the role of and the potential interaction of mast cells with radiation-induced tissue injury and alterations in normal tissue integrity.
Br J Cancer 1994 Feb
PMID:Increase in mast cells and hyaluronic acid correlates to radiation-induced damage and loss of serous acinar cells in salivary glands: the parotid and submandibular glands differ in radiation sensitivity. 829 28

A 24-year-old man had a mediastinal embryonal carcinoma containing yolk sac foci. Combination chemotherapy with cisplatin, bleomycin, etoposide, and vinblastine was given, and the residual mass was then resected. Histology showed only necrotic cells. No other treatment was given. Two years later the patient presented with episodes of flushing and syncopes related to a systemicmastocytosis. Bone marrow examination showed a diffuse infiltration with large, atypical mast cells often with multilobulated nuclei. The patient suffered several episodes of cardiovascular collapse and died during one of these episodes, 8 months after the diagnosis of systemic mastocytosis and 40 months after the diagnosis of mediastinal tumor. Autopsy findings included the absence of mediastinal tumor and a diffuse liver and spleen mast cell infiltration. This was the second case with the similar clinicopathologic picture of two rare diseases being associated. This fact supports the hypothesis of a distinct entity, part of the mediastinal germ cell tumor/hematologic malignancy syndrome. The hypothesis of a cytokine secretion induced by mediastinal germ cell tumor supporting mast cell proliferation may be considered.
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PMID:Systemic mastocytosis following mediastinal germ cell tumor: an association confirmed. 838 Feb 74

We have previously shown that v-erb-B contained within a recombinant murine retroviral vector is capable of transforming pre-B lymphocytes (M. Miller, A. K. Kennewell, and G. Symonds, Leukemia, 6: 18-28, 1992) and early erythroid precursor cells [blast-forming units (erythroid) (M. Miller, A. Kennewell, Y. Takayama, A. Bruskin, J. M. Bishop, G. Johnson, and G. Symonds, Oncogene, 5: 1125-1131, 1990)] in vitro. To determine the sites and nature of v-erb-B-induced transformation in vivo, the hematopoietic systems of lethally irradiated mice were repopulated with v-erb-B-infected bone marrow. All mice became moribund within 4-12 weeks of reconstitution, with a median onset of disease at 6 weeks. Histopathological and flow cytometric evaluation of tissues from diseased mice, as well as morphological and phenotypic analysis (cytochemical as well as molecular) of the cell lines established from the mice, revealed that all but one of the mice examined at postmortem had developed a pre-B lymphoid leukemia or lymphoma. Abnormally high levels of mast cells in the spleen and bone marrow of the remaining mouse indicated a mast cell disease. The development of pre-B lymphoid malignancy in the majority of the reconstituted mice indicates a marked predisposition of v-erb-B to transform cells of the pre-B lymphoid lineage. The reconstitution of lethally irradiated mice with v-erb-B virus-infected bone marrow provides a model system for the analysis of events involved in the initiation and maintenance of acute lymphoid leukemia.
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PMID:Induction of pre-B lymphoid leukemia following reconstitution of lethally irradiated mice with v-erb-B virus-infected bone marrow progenitor cells. 849 83

Monoclonal antibody 4E3 directed against a glycosylated surface protein on human ovarian teratocarcinoma cells (CRL-1572 cell line) was conjugated to bovine carboxypeptidase A (CPA) using a 3400 Da polyethylene glycol chain bearing an N-hydroxysuccinimide group at both ends. The conjugate preparation was purified by fast protein liquid chromatography on a Superose 12/30 HR column. The 4E3-CPA conjugate was recovered in the third fraction by SDS-PAGE analysis. The specific binding of the 4E3-CPA conjugate to CRL-1572 cells was confirmed by a FACS analysis and the enzymatic activity of the conjugate remained while tested with hippuryl-L-phenylalanine. In vitro cytotoxic assays on CRL-1572 cells showed that the prodrug methotrexate-phenylalanine (MTX-Phe) alone was non-toxic (ID50 > 1000 ng ml-1) but was selectively converted to MTX when the cells were pretreated with 50 micrograms ml-1 4E3-CPA conjugate, which enhanced considerably the pharmacological activity of the prodrug with an ID50 of 70 ng ml-1. The co-culture assays with CRL-1572 and MRC-5 cells (human normal lung diploid fibroblast cell lines) demonstrated the specificity of the 4E3-CPA conjugate for the CRL-1572 cells since no cytotoxicity was observed on the MRC-5 cells. When both cell lines were mixed in ratios ranging from 1:10,000 to 1:5 (CRL-1572:MRC-5), the significant increase in the ID25 was correlated with the proportion of tumoral cells present in the cell inoculum. These results suggest that MTX-Phe combined with 4E3-CPA conjugate is a promising model for a more selective and localised anti-cancer chemotherapy based on the ADEPT concept.
Br J Cancer 1996 Feb
PMID:Activation of methotrexate-phenylalanine by monoclonal antibody--carboxypeptidase A conjugate for the specific treatment of ovarian cancer in vitro. 856 31

Stem cell factor receptor (SCFR, c-kit), normally expressed on haematopoietic and mast cells, plays a regulatory role in cellular growth and differentiation. Dysregulated expression of SCFR may contribute to neoplastic transformation. We investigated expression of SCFR on malignant canine mast cells obtained directly from spontaneous canine mast cell neoplasms, in an attempt to determine whether these undifferentiated cells maintained expression of this growth-promoting cytokine receptor. Malignant mast cells (histological grade 2) from skin tumours or lymph node metastases were collected from canine patients, and SCFRs were detected by flow cytometric analysis of these cells. All of the tumours bound mouse and canine recombinant stem cell factor (SCF), indicating that the cells not only expressed SCFRs, but that the receptors possessed the functional property of ligand binding. Immunoglobulin Fc receptors for canine IgE were identified on these cells by flow cytometry, a further indication that the cells analysed were mast cells and retained some differentiated features. Immunohistochemical analysis of formalin-fixed, paraffin wax-embedded mast cell tumour biopsies confirmed expression of SCFRs by malignant cells from each tumour. The relative binding of SCF to suspensions of tumour cells, as assessed by flow cytometry, correlated with the intensity of immunolabelling for SCFR in sections of the same tumours, suggesting variability in SCFR expression between tumours. Agarose gel electrophoresis of the products of SCFR reverse transcription-polymerase chain reaction derived from each tumour had the molecular weight predicted for canine SCFR cDNA on the basis of the mouse and human counterparts. This further confirmed SCFR expression by malignant canine mast cells. Taken together, these results show that a membrane receptor capable of triggering cell growth is expressed by malignant canine mast cells, suggesting a role for this receptor in the aetiology of canine mast cell cancer. This relatively common malignancy of the dog would seem to present an opportunity for the investigation of the potential role of the SCF/SCFR pathway in the development of spontaneous malignancies of mast cells.
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PMID:Expression of stem cell factor receptor (c-kit) by the malignant mast cells from spontaneous canine mast cell tumours. 900 81


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