Disease relevance of Thymoma

• We have applied spectral karyotyping (SKY) to chemically induced plasmocytomas, mammary gland tumours from transgenic mice overexpressing the c-myc oncogene and thymomas from mice deficient for the ataxia telangiectasia (Atm) gene [1].
• We have studied the integrated proviruses in Moloney murine leukemia virus-induced rat thymomas [2].
• A cDNA library was prepared from a terminal deoxynucleotidyltransferase-containing thymoma in the lambda phage vector lambda gt11 [3].
• The analogs were produced in E. coli, purified to homogeneity, and assayed for biological activity on murine thymocytes, human rheumatoid synovial cells, and human dermal fibroblasts and for their ability to bind to IL-1 receptors on murine EL-4 thymoma cells [4].
• Because many thymomas are enriched with autoantigen-specific T cells, a disturbance of circulating T-cell subset composition by export of intratumorous T cells may contribute to paraneoplastic autoimmune disease arising in patients with thymoma [5].

High impact information on Thymoma

• The W7 mouse thymoma cell line does not express the metallothionein-I (MT-I) gene in the presence of either cadmium or glucocorticoids, unlike most other cell lines [6].
• DNAs from three different M-MuLV-induced thymomas indicate, as in rat cells, multiple possible integration sites [7].
• The LSTRA Moloney murine leukaemia virus (M-MuLV)-induced thymoma cell line contains approximately 20-fold more phosphotyrosine in protein than do typical haematopoietic cell lines; this seems to result from the expression of an abnormally high level of a cellular tyrosine protein kinase termed p56tck (refs 3, 4) [8].
• We have attempted to detect the null receptor in WEHI-7 mouse thymoma cells with a monoclonal antibody to the glucocorticoid receptor [9].
• We have fused an established, T-cell growth factor (TCGF)-dependent murine cytolytic T-lymphocyte (CTL) line with a mouse thymoma line and have obtained hybrids with cytolytic activity when we selected the hybrids in TCGF-containing medium, while hybrids isolated in the absence of growth factor showed no detectable cytolytic potential [10].

Chemical compound and disease context of Thymoma

• In intact EL4 thymoma cells, IL-1 beta similarly stimulated a rapid decrease of sphingomyelin and an elevation of ceramide, and enhanced ceramide-activated protein kinase activity [11].
• CSA also blocked lymphokine release from a phorbol myristate acetate-stimulated thymoma cell line, EL-4 [12].
• Specific-pathogen-free inbred C57BL/Cbi mice (adult virgin females) were given single sublethal doses of N-methyl-N-nitrosourea or N-ethyl-N-nitrosourea and were studied for a lifetime for the development of thymomas [13].
• The cholesterol and plasmalogen contents of membranes from both sources were similar, but the phospholipid content of the benign thymoma lymphoid cell membranes was slightly lower than that of the normal thymocytes, resulting in a somewhat higher molar ratio of cholesterol to phospholipid [14].
• Detection of a recombinant murine leukemia virus-related glycoprotein on virus-negative thymoma cells [15].

Biological context of Thymoma

• By introducing a RAG-1 deficiency into Atm-/- mice in the presence of a TCR transgene, we show that V(D)J recombination is critical for thymoma development in these mice [16].
• We identified the constitutively active intracellular fragment of murine Notch-1 as capable of rendering thymomas resistant to glucocorticoid-induced apoptosis [17].
• The expression of anti-sense RNA to SRG3 mRNA in a thymoma cell line, S49.1, reduced the expression level of the SRG3 protein, and decreased the apoptotic cell death induced by glucocorticoids [18].
• Trisomy no. 15 in murine thymomas induced by chemical carcinogens, X-irradiation, and an endogenous murine leukemia virus [19].
• Using thymoma cells transfected with hybrid genes constructed by exchanging exons between Q7b and H-2Db, the signals for PtdIns modification were localized to a defined region of Qa-2 [20].

Anatomical context of Thymoma

• 30 thymomas were characterized by the presence of MuLV p30 at levels of 1-10 ng/mg protein, levels that were comparable to those found in thymus extracts from age-matched, nonirradiated control [21].
• Murine B cell stimulating factor 1 (BSF-1) was purified to homogeneity from supernatants of a stimulated thymoma cell line [22].
• Hybridomas secreting a monoclonal T suppressor-effector factor (TseF) were produced by fusion of a lactate dehydrogenase B (LDHB)-specific long-term T suppressor-effector (Tse) cell line with the BW5147 thymoma [23].
• The thymoma epithelial cells (specifically identified by their keratin content) contained thymic hormones (thymulin and thymosin alpha 1), a finding corroborated by the observation of elevated thymulin serum levels [24].
• To identify gene products which might be involved in glucocorticoid-induced responses in lymphoid cells, we constructed a lambda cDNA library prepared from murine thymoma WEHI-7TG cells treated for 5 h with glucocorticoids and forskolin [25].

Gene context of Thymoma

• In this report, we studied the relative roles of B7-1 and B7-2 molecules in the induction of antitumor immunity to the T cell thymoma, EL4 [26].
• A new mouse gene, SRG3, related to the SWI3 of Saccharomyces cerevisiae, is required for apoptosis induced by glucocorticoids in a thymoma cell line [18].
• Interleukin 2 (IL-2) production was studied in a subclone of the murine thymoma EL 4 [27].
• V(D)J recombination was dispensable for tumorigenesis since thymomas developed with or without the RAG-1 or RAG-2 gene, although some delay was observed [28].
• The unusual disease association with a CTLA4high genotype implies a unique pathogenesis of paraneoplastic MG, with high CTLA4 levels possibly supporting the nontolerogenic selection of CD4+ T cells in MG-associated thymomas [29].

Analytical, diagnostic and therapeutic context of Thymoma

• When enriched CId-1+ splenic T cells from NAGA-immune BALB/c mice were fused with the AKR thymoma BW 5147 cell line, 2 of 72 resulting hybrids, termed CId-1A and CId-1B, were reactive by indirect immunofluorescence with the CId-1 antibody [30].
• Production of interferon by phorbol myristate acetate-stimulated BFS cell cultures was synergistically increased by the addition of EL4 thymoma cell culture supernatants [31].
• In both strains thymomas arose with short latent periods, comparable with the latencies of nonthymic tumors induced by intraperitoneal injection of A-MuLV and significantly shorter than those of thymomas induced by intrathymic injection of Moloney leukemia virus [32].
• PATIENTS AND METHODS: Assessable patients with thymoma (n = 29) or thymic carcinoma (n = 1) with metastatic or locally progressive recurrent disease following radiotherapy were treated with intravenous cisplatin (50 mg/m2), doxorubicin (50 mg/m2), and cyclophosphamide (500 mg/m2) with normal saline hydration [33].
• Western thymomas lack Epstein-Barr virus by Southern blotting analysis and by polymerase chain reaction [34].

References