Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ewing's sarcoma (ES), most commonly an undifferentiated tumor of bone, belongs to the enigmatic diagnostic category of small round cell tumors (SRCT) of childhood. The consistent presence of the translocation t (11; 22) in the vast majority of tumors provides evidence for a common histogenesis in ES and its family of tumors (ESFT), and also provides a unique diagnostic characteristic to discriminate this tumor family from SRCT. Molecular analysis of this translocation has revealed that it forms a chimeric gene between EWS on chromosome 22 and FLI-1 on chromosome 11. Similarly, the variant t (21; 22), t (7; 22), t (17; 22), and t (2; 22) rearrangements also form chimeric genes between regions of EWS and the ETS gene family (ERG, ETV1, E1AF, and FEV). Detection of these specific chimeric genes would provide a method for diagnosis of ESFT. We have developed a procedure for simultaneous detection of the chimeric genes by reverse transcription polymerase chain reaction (RT-PCR) with a mixture of primers. We conclude that the detecting those chimeric genes by this method can be easy and useful for diagnosis of ESFT. Moreover, by defining the specific chimeric gene it is possible to detect the tumor cell contamination in autologous blood stem cell transplantation.
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PMID:Detection of chimeric genes in Ewing's sarcoma and its clinical applications. 1218 32

We utilized gene targeting by homologous recombination to define the role that MEF, a transcriptional activating member of the ETS family of transcription factors, plays in lymphopoiesis. MEF-/- mice have a profound reduction in the number of NK-T and NK cells. Purified MEF-/- NK cells cannot lyse tumor cell targets and secrete only minimal amounts of IFNgamma. Perforin protein expression is severely impaired in MEF-deficient NK cells, likely accounting for the lack of tumor cell cytotoxicity. Promoter studies and chromatin immunoprecipitation analyses demonstrate that MEF and not ETS-1 directly regulates transcription of the perforin gene in NK cells. Our results uncover a specific role of MEF in the development and function of NK cells and in innate immunity.
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PMID:The ETS protein MEF plays a critical role in perforin gene expression and the development of natural killer and NK-T cells. 1238 38

TEL is a nuclear phosphoprotein that belongs to a member of the ETS family transcription factors. TEL acts as a tumor suppressor and is essential for establishing hematopoiesis in neonatal bone marrow. Because TEL possesses multiple putative mitogen-activated protein (MAP) kinase phosphorylation sites, we here investigated functional regulation of TEL via stress signaling pathways. We showed that TEL becomes phosphorylated in vivo by activated p38 but not by JNK1. The constitutive and inducible phosphorylation sites were found to be Ser(22) and Ser(257), respectively. TEL bound to p38 and was directly phosphorylated in vitro by p38. In vivo p38-dependent phosphorylation reduced trans-repressional abilities of TEL through ETS-binding consensus site. These data indicate that TEL's functions are potentially regulated by p38 which is activated by various kinds of stresses. TEL could be a constituent downstream of the specific MAP kinase in the signal transduction system.
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PMID:Functional regulation of TEL by p38-induced phosphorylation. 1243 97

Although X chromosome transfer experiments indicated that tumor suppressor genes are present on the X chromosome, they have not been previously identified. In this report, we show that the ETS transcription factor MEF (ELF4), which is located on chromosome Xq26.1, possesses tumor suppressive capability. MEF expression was up-regulated by 5-azacytidine in some cancer cell lines. MEF overexpression induced morphological changes, such as the conversion of normally loose cell-cell contacts to strong interactions similar to those seen in the presence of matrix metalloproteinase (MMP) inhibitor BB94. In the colony formation assay, A549 cells, but not MEF-overexpressing cells, formed colonies in soft agar culture. Furthermore, MEF-overexpressing cells s.c. injected in the nude mice did not grow, whereas the control cells did. The A549 tumors were poorly differentiated, whereas the MEF-overexpressing tumors were well differentiated. By immunostaining with CD31, a marker on vascular endothelial cells, we found that tumor angiogenesis was significantly suppressed in the tumors formed from MEF-overexpressing cells. In addition, the conditioned media from A549 cell cultures stimulated the migration of human umbilical vein endothelial cells, whereas conditioned media from MEF-overexpressing cell cultures had less of an effect. By gelatin zymography, Western blotting analysis, and immunohistochemistry, we found that the expression levels of MMP-9 and MMP-2 were significantly reduced in MEF-overexpressing tumors. Immunohistochemical analyses showed that interleukin (IL)-8 expression was reduced in the MEF-overexpressing tumors in nude mice. Furthermore, IL-8 mRNA expression in vitro was significantly down-regulated in MEF-overexpressing cells, compared with A549 cells. MEF suppressed the transcription and promoter activities of the genes encoding MMP-9 and IL-8, whereas ETS-2 up-regulated these activities. Therefore, we propose that MEF is a candidate tumor suppressor gene on the X chromosome with activities that are opposite to those of ETS-2.
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PMID:The ETS transcription factor MEF is a candidate tumor suppressor gene on the X chromosome. 1243 53

Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumors (PNETs) are associated with a chromosomal translocation resulting in a fusion of the amino-terminus of EWS with the DNA-binding domain of an ETS transcription factor (most commonly FLI1 or ERG). Although previous reports suggested that these chimera proteins would act as aberrant transcription factors, their downstream targets have not been fully elucidated. To identify downstream targets of these EWS-ETS fusion proteins, we introduced EWS-ETS fusion constructs into a human fibrosarcoma cell line, HT-1080, by retroviral transduction. Here we report that Tenascin-C (TNC) is induced to a significantly higher level in cells expressing EWS-ETSs than in cells expressing normal ETSs. Furthermore, through use of an antisense cDNA expression vector we show that expression of endogenous TNC mRNA and protein were reduced coordinately with attenuation of EWS-FLI1 fusion protein expression. A chromatin immunoprecipitation assay showed direct interaction between the TNC promoter and the EWS-FLI1 fusion protein in vivo. In addition, a luciferase reporter assay revealed that EWS-ETSs upregulated the TNC gene through four ETS binding sites in the TNC promoter. High levels of TNC expression were observed in a subset of ES cell lines (3 of 6) and primary tumors (4 of 6). Together with previous studies showing that TNC expression is involved in the invasive and malignant phenotype of several tumor types, our data suggest that the oncogenic effect of EWS-ETS may be mediated in part by upregulating of TNC expression.
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PMID:Induction of tenascin-C by tumor-specific EWS-ETS fusion genes. 1255 22

Translocation t(11;22) is a karyotypic abnormality detected in over 90% of Ewing's family tumors. This translocation results in the EWS-Fli1 fusion gene, which has been shown to be a potent, single-step transforming gene. We reported previously that suppression of the EWS-Fli1 fusion protein altered the expression of G(1) regulatory cyclins and cyclin-dependent kinase inhibitors both at mRNA and protein levels, resulting in G(1) growth arrest in Ewing's family tumor cell lines. These data suggest that the G(1) regulatory molecules may be targets of the EWS-Fli1 fusion protein, which functions as an aberrant transcription factor. By using electrophoretic mobility shift assays, we show here the direct association of EWS-Fli1 fusion protein with ETS consensus sequences, which are in the promoter of the p21(WAF1/CIP1) gene. Reporter gene assays revealed that the activity of the p21(WAF1/CIP1) promoter is negatively regulated by EWS-Fli1 fusion protein through at least two ETS-binding sites in the promoter. EWS-Fli1 interacted with p300 cotransactivator and suppressed its histone acetyltransferase activity, which may explain the down-regulation of p21(WAF1/CIP1) by EWS-Fli1. In the presence of a histone deacetylase inhibitor, the histone acetyltransferase activity of the Ewing's family tumor cell was recovered resulting in the induction of p21, and the cell growth was dramatically inhibited. These results demonstrated that p21(WAF1/CIP1) might be one of the direct targets of EWS-Fli1, and that p21(WAF1/CIP1) could serve as a target for a molecularly based therapy for Ewing's family tumors.
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PMID:Identification of p21WAF1/CIP1 as a direct target of EWS-Fli1 oncogenic fusion protein. 1256 Mar 28

The remodeling of extracellular matrix (ECM) is an important process required for cancer cells to turn into invasive and metastatic cancer cells. To dissolve the protein components of ECM, matrix metalloproteinases are some of the essential enzymes. Another ECM remodeling enzyme is the heparanase (Hpa) that digests the heparin sulfate component of the matrix. In metastatic cancer cells the Hpa gene is upregulated. To investigate the mechanism of why Hpa was upregulated in metastatic cancer cells, the regulatory sequence of heparanase gene was isolated and its function analysed in metastatic breast cancer cells. We found there are four ETS transcription factor binding sites. Two of them flanking the transcription initiation of the Hpa gene are nonfunctional, whereas two others are highly functional and responded to exogenously added ETS transcription factors. Mutation of these two ETS binding sites abolished the transcriptional activation of Hpa promoter by ETS transcription factors. Among four transcription factors tested (ETS1, ETS2, PEA3, and ER81), ETS1 and ETS2 are more potent in transactivating the human Hpa gene. Furthermore, dominant-negative ETS transcription factors failed to transactivate Hpa promoter and could abrogate the function of wild-type transcription factor in transactivation activity of ETS transcription factors on the Hpa promoter. These results suggest that ETS transcription factors play an important role in tumor invasion and metastasis by modulating the remodeling of ECM.
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PMID:Trans-activation of heparanase promoter by ETS transcription factors. 1258 71

H-L(3)MBT, the human homolog of the Drosophila lethal(3)malignant brain tumor protein, is a member of the polycomb group (PcG) of proteins, which function as transcriptional regulators in large protein complexes. Homozygous mutations in the l(3)mbt gene cause brain tumors in Drosophila, identifying l(3)mbt as a tumor suppressor gene. The h-l(3)mbt gene maps to chromosome 20q12, within a common deleted region associated with myeloid hematopoietic malignancies. H-L(3)MBT contains three repeats of 100 residues called MBT repeats, whose function is unknown, and a C-terminal alpha-helical structure, the SPM (SCM, PH, MBT domain, which is structurally similar to the SAM (sterile alpha motif) protein-protein interaction domain, found in several ETS transcription factors, including TEL (translocation Ets leukemia). We report that H-L(3)MBT is a transcriptional repressor and that its activity is largely dependent on the presence of a region containing the three MBT repeats. H-L(3)MBT acts as a histone deacetylase-independent transcriptional repressor, based on its lack of sensitivity to trichostatin A. We found that H-L(3)MBT binds in vivo to TEL, and we have mapped the region of interaction to their respective SPM/SAM domains. We show that the ability of TEL to repress TEL-responsive promoters is enhanced by the presence of H-L(3)MBT, an effect dependent on the H-L(3)MBT and the TEL interacting domains. These experiments suggest that histone deacetylase-independent transcriptional repression by TEL depends on the recruitment of PcG proteins. We speculate that the interaction of TEL with H-L(3)MBT can direct a PcG complex to genes repressed by TEL, stabilizing their repressed state.
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PMID:The human L(3)MBT polycomb group protein is a transcriptional repressor and interacts physically and functionally with TEL (ETV6). 1258 62

Several members of the ETS family of transcription factors contribute to tumorigenesis in many different tissues, including breast epithelium. The ESX gene is an epithelial-specific Ets member that is particularly relevant to breast cancer. ESX is amplified in early breast cancers, it is overexpressed in human breast ductal carcinoma in situ, and there may be a positive feedback loop between the HER2/neu proto-oncogene and ESX. Despite this progress in our understanding of ESX, its ability to regulate tumor-related gene expression and to modulate breast cell survival, remain unknown. Here we show that HA-ESX stimulates the collagenase and HER2/neu promoters, but fails to activate an intact stromelysin promoter. However, HA-ESX activates, in a dose-dependent manner, a heterologous promoter containing eight copies of the Ets binding site derived from the stromelysin gene (p8Xpal-CAT). Analysis of the ability of constructs encoding nine Ets family members to activate the HER2/neu promoter revealed three patterns of gene activation: (1) no effect or repressed promoter activity (Elk-1 and NET); (2) intermediate activity (ER81, GABP, ESX, and HA-Ets-2); and, (3) maximal activity (Ets-1, VP-16-Ets-1, and EHF). Based on these observations, we also determined whether ESX is capable of conferring a survival phenotype upon immortalized, but nontransformed and ESX negative MCF-12A human breast cells. Using a colony formation assay, we found that HA-ESX and HA-Ets-2, mediated MCF-12A cell survival rates that approached those generated by oncogenic V12 Ras, whereas empty vector resulted in negligible colony formation. By contrast, in immortalized and transformed T47D breast cancer cells, which express both HER2/neu and ESX, we found that antisense and dominant-negative HA-ESX inhibited T47D colony formation, whereas control vector allowed formation of many colonies. These results are significant because they show that HA-ESX is able to differentially activate several malignancy-associated gene promoters, and that ESX expression is required for cellular survival of nontransformed MCF-12A and transformed T47D human mammary cells.
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PMID:The epithelial-specific ETS transcription factor ESX/ESE-1/Elf-3 modulates breast cancer-associated gene expression. 1271 34

Toxicology and carcinogenesis studies of erythromycin stearate (USP grade, greater than 96% pure) were conducted by administering the antibiotic in feed to groups of F344/N rats and B6C3F1 mice of each sex for 14 days, 13 weeks, or 2 years. Erythromycin stearate was studied because of its widespread use in humans as a broad-spectrum macrolide antibiotic and because of the lack of adequate long-term studies for carcinogenicity. Fourteen-Day and Thirteen-Week Studies: In the 14-day studies, none of the rats (at dietary concentrations up to 50,000 ppm) and 2/5 female mice that received 50,000 ppm died before the end of the studies. Final mean body weights of male rats that received 12,500, 25,000, or 50,000 ppm were 10%, 30%, or 36% lower, respectively, than that of controls; final mean body weights of female rats were 10%, 12%, or 32% lower. None of the dosed mouse groups gained weight. The final mean body weight of male mice that received 50,000 ppm was 10% lower than that of controls. In the 13-week studies, none of the rats or mice (at dietary concentrations up to 20,000 ppm) died before the end of the studies. Final mean body weights of the 20,000-ppm groups of rats were more than 12% lower than that of the controls for males and 7% lower for females. Final mean body weights of mice that received 10,000 or 20,000 ppm were 15% or 19% lower than that of controls for males and 5% or 14% lower for females. Multinucleated syncytial hepatocytes were observed in 10/10 male rats that received 20,000 ppm but in 0/10 male rats that received 10,000 ppm. No compound-related gross or microscopic pathologic effects were observed in mice. Based on these results, 2-year studies of erythromycin stearate were conducted by feeding diets containing 0, 5,000, or 10,000 ppm erythromycin stearate to groups of 50 rats of each sex for 103 weeks. Diets containing 0, 2,500, or 5,000 ppm were fed to groups of 50 mice of each sex for 103 weeks. Body Weight and Survival in the Two-Year Studies: Mean body weights of high dose male rats were comparable to those of controls throughout the studies. Mean body weights of high dose female rats were 5%-10% lower than those of controls. Mean body weights of dosed and control mice were comparable. The average daily feed consumption was similar for dosed and control male and female rats. For mice, estimated daily feed consumption by low and high dose males was similar to that of the controls and by low and high dose females was 92% that of the controls. The average amount of erythromycin stearate consumed per day was approximately 180 or 370 mg/kg for male rats and 210 or 435 mg/kg for female rats; for mice, the average amounts were 270 or 545 mg/kg for males and 250 or 500 mg/kg for females. No significant differences in survival were observed between any groups of rats or mice of either sex (final survival-- male rats: control, 28/50; low dose, 23/50; high dose, 27/50; female rats: 29/50; 30/50; 38/50; male mice: 34/50; 33/50; 40/50; female mice: 38/50; 34/50; 40/50). Nonneoplastic and Neoplastic Effects in the Two-Year Studies: Granulomas of the liver were observed at increased incidences in high dose rats (male: 1/50; 2/50; 10/50; female: 18/50; 27/50; 43/50). Granulomatous inflammation or granulomas of the spleen were observed in dosed female rats (0/48; 1/49; 3/50). Reticulum cell hyperplasia in the bone marrow occurred at increased incidences in high dose female rats (10/50; 14/50; 25/50). Squamous cell papillomas of the oral mucosa were observed in 1/50 control, 2/50 low dose, and 3/50 high dose female rats. These tumors were considered to be marginal and not related to exposure. Hyperplasia of the oral mucosa was not observed. Pheochromocytomas of the adrenal gland in female rats occurred with a positive trend (1/50; 4/49; 5/50). The incidences in the dosed groups are similar to the average historical incidence (9%) of this tumor in untreated control female F344/N rats at the study laboratory. This marginal tumor increase is not considered to be biologically important. No increases in incidences of study laboratory. This marginal tumor increase is not considered to be biologically important. No increases in incidences of neoplasms were observed at any site in dosed male rats. Inflammation in the glandular stomach was observed at increased incidences in dosed male mice (1/49; 4/50; 6/50). Lymphoid hyperplasia in the urinary bladder was observed at increased incidences in dosed female mice (1/50; 9/47; 7/48). No increases in incidences of neoplasms were observed at any site in dosed male or female mice. Genetic Toxicology: Erythromycin stearate was not mutagenic in Salmonella typhimurium strains TA98, TA100, TA1535, or TA1537 when tested both with or without exogenous metabolic activation. Erythromycin stearate demonstrated equivocal mutagenicity in the mouse L5178Y lymphoma cell assay in the absence of exogenous metabolic activation (S9); erythromycin stearate was not mutagenic in the presence of S9. Treatment of cultured Chinese hamster ovary cells with erythromycin stearate did not produce an increase in the frequency of sister chromatid exchanges or chromosomal aberrations in either the presence or absence of metabolic activation. Audit: The data, documents, and pathology materials from the 2-year studies of erythromycin stearate have been audited. The audit findings show that the conduct of the studies is documented adequately and support the data and results given in this Technical Report. Conclusions: Under the conditions of these 2-year studies, there was no evidence of carcinogenic activity of erythromycin stearate for male or female F344/N rats administered erythromycin stearate in the diet at 5,000 or 10,000 ppm. There was no evidence of carcinogenic activity of erythromycin stearate for male or female B6C3F1 mice administered erythromycin stearate in the diet at 2,500 or 5,000 ppm. Dose-related increases in the incidences of granulomas of the liver were observed in male and female rats. The absence of any biologically important chemical-associated effects in mice suggests that higher doses could have been given to male and female mice. Synonyms: erythrocin stearate; erythromycin octadecanoate Trade Names: Abbotcine; Bristamycin; Dowmycin E; Eratrex; Erypar; Ethril; Gallimycin; HSDB 4178; OE 7; Pantomicina; Pfizer-E; SK-Erythromycin; Wyamycin S
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PMID:NTP Toxicology and Carcinogenesis Studies of Erythromycin Stearate (CAS No. 643-22-1) in F344/N Rats and B6C3F1 Mice (Feed Studies). 1273 98


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