Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four embryonal rhabdomyosarcomas, one tumor diagnosed as an undifferentiated sarcoma, probably a rhabdomyosarcoma, and six different non-muscular sarcomas were investigated with antibodies specific for different intermediate filament types. The tumor cells in the rhabdomyosarcomas and the undifferentiated tumor were stained clearly by antibodies to desmin, the intermediate filament type characteristic of muscle. The staining of tumor cell by antibodies to vimentin, the intermediate filament type characteristic of certain cell types of mesenchymal origin including myoblasts, was different in these 5 cases. In one case of embryonal rhabdomyosarcoma nearly all tumor cells were stained, but in the remaining cases few or no tumor cells were positive with the vimentin antibody. In these rhabdomyosarcomas not only the large rhabdomyoblasts, but also the small undifferentiated cells were labeled by antibodies to desmin. In the latter cell type the desmin filaments were arranged typically in coils. In contrast, tumor cells in the non-muscular mesenchymal sarcomas were stained only by antibodies to vimentin but not by antibodies to desmin or prekeratin. The retention of the desmin marker characteristic of normal muscle in cases of rhabdomyosarcoma not only allowed the undifferentiated desmin-positive sarcoma to be classified as rhabdomyosarcoma but also suggests that the use of antibodies to desmin could be very helpful in the future for the diagnosis of undifferentiated rhabdomyosarcomas.
Virchows Arch B Cell Pathol Incl Mol Pathol 1982
PMID:Diagnosis of human childhood rhabdomyosarcoma of antibodies to desmin, the structural protein of muscle specific intermediate filaments. 617 91

Pharmacological properties of the (+)- and (-)-isomers of synthetic epibatidine, exo-2-(6-chloro-3-pyridyl)-7-azabicyclo-[2.2.1]heptane, were compared with nicotine and acetylcholine on several subtypes of chicken and human nicotinic acetylcholine receptors (AChRs). Both isomers of epibatidine behaved as extremely potent full agonists on chicken (alpha 3 beta 2, alpha 3 beta 4, alpha 4 beta 2, alpha 7, and alpha 8) and human (alpha 3 beta 2, alpha 3 beta 4, and alpha 7) neuronal AChRs expressed in Xenopus oocytes. Currents induced by epibatidine were effectively blocked by the nicotinic antagonists hexamethonium and mecamylamine. Apparent affinity was 100 to 1000-fold higher for epibatidine than for nicotine or acetylcholine. EC50 values ranged from 1 nM (for homomeric chicken alpha 8) to 2 microM (for homomeric chicken alpha 7). Epibatidine showed comparatively lower affinity for muscle-type AChRs from Torpedo and humans (EC50 values, 1.6 and 16 microM respectively). In binding assays, epibatidine was used on AChR subtypes immunoisolated from chicken brain and retina (alpha 4 beta 2, alpha 7, and alpha 8), the human neuronal cell line SH-SY5Y (alpha 3 and alpha 7), Torpedo electric organ (alpha 1 beta 1 gamma delta), or the human rhabdomyosarcoma cell line TE671 (alpha 1 beta 1 gamma delta). Both isomers of epibatidine exhibited extremely high affinity for all neuronal AChRs tested, with KI values ranging from 0.6 pM (human alpha 3 AChRs) to 0.6 microM (chicken alpha 7 AChRs). In contrast, epibatidine had lower affinity for Torpedo muscle-type AChRs (KI approximately 5 microM). Racemic [3H]epibatidine was an effective labeling reagent for human alpha 3 beta 2 AChRs, exhibiting a KD (0.14 nM) similar to the KI values observed for unlabeled (+)-epibatidine (0.23 nM) or (-)-epibatidine (0.16 nM).
Mol Pharmacol 1995 Oct
PMID:Comparative pharmacology of epibatidine: a potent agonist for neuronal nicotinic acetylcholine receptors. 747 6

In the present study we have analysed the expression of insulin-like growth factor II (IGF-II) in the human rhabdomyosarcoma cell line IN157.IN157 cells express high levels of three IGF-II mRNAs of 6.0 kb, 4.8 kb and 4.2 kb. In contrast, normal skeletal muscle expresses a negligible amount of IGF-II mRNA. Two forms of IGF-II with molecular masses of 7.5 kDa and 10 kDa, corresponding to the mature IGF-II and IGF-II with a C-terminal extension of 21 amino acids (IGF-IIE21), were secreted into the culture medium at amounts of 17 ng/ml (2.3 nM) and 15 ng/ml (1.5 nM), respectively. IN157 cells also produce IGF binding protein-2. The bioactivity of recombinant IGF-IIE21 was compared with human IGF-I and IGF-II. IGF-I, IGF-II and IGF-IIE21 bound with high affinity to human IGF-I receptors (Kd approximately 1 nM), whereas the human IGF-II/mannose 6-phosphate (IGF-II/Man 6-P) receptor bound IGF-II and IGF-IIE21 with Kd values of 0.5 nM and 2 nM, respectively, and IGF-I with about 500 times lower affinity. IGF-II and IGF-IIE21 stimulated DNA synthesis via the IGF-I receptor, whereas the IGF-II/Man 6-P receptor mediated their rapid internalization and inactivation. During culture of IN157 cells about 50% of their IGF-I receptors were occupied by endogenous IGF-II. We conclude that IN157 cells express high levels of bioactive 10 kDa IGF-II and 7.5 kDa IGF-II that may stimulate the proliferation of rhabdomyosarcomas by interaction with IGF-I receptors on the cells.
Mol Cell Endocrinol 1993 May
PMID:Biosynthesis of 10 kDa and 7.5 kDa insulin-like growth factor II in a human rhabdomyosarcoma cell line. 768 19

2 mM Ascorbic acid has a potent cytotoxic effect on neuroblastoma, osteosarcoma, retinoblastoma, and rhabdomyosarcoma cells cultured in vitro. At a lower concentration (0.2 mM), ascorbic acid remains highly cytotoxic for neuroblastoma, osteosarcoma and retinoblastoma cells, but it has a stimulatory effect on the growth of rhabdomyosarcoma cells.
Biochem Mol Biol Int 1994 Nov
PMID:Ascorbic acid is cytotoxic for pediatric tumor cells cultured in vitro. 770 4

Alveolar rhabdomyosarcomas are pediatric solid tumors with a hallmark cytogenetic abnormality: translocation of chromosomes 2 and 13 [t(2;13) (q35;q14)]. The genes on each chromosome involved in this translocation have been identified as the transcription factor-encoding genes PAX3 and FKHR. The NH2-terminal paired box and homeodomain DNA-binding domains of PAX3 are fused in frame to COOH-terminal regions of the chromosome 13-derived FKHR gene, a novel member of the forkhead DNA-binding domain family. To determine the role of the fusion protein in transcriptional regulation and oncogenesis, we identified the PAX3-FKHR fusion protein and characterized its function(s) as a transcription factor relative to wild-type PAX3. Antisera specific to PAX3 and FKHR were developed and used to examine PAX3 and PAX3-FKHR expression in tumor cell lines. Sequential immunoprecipitations with anti-PAX3 and anti-FKHR sera demonstrated expression of a 97-kDa PAX3-FKHR fusion protein in the t(2;13)-positive rhabdomyosarcoma Rh30 cell line and verified that a single polypeptide contains epitopes derived from each protein. The PAX3-FKHR protein was localized to the nucleus in Rh30 cells, as was wild-type PAX3, in t(2;13)-negative A673 cells. In gel shift assays using a canonical PAX binding site (e5 sequence), we found that DNA binding of PAX3-FKHR was significantly impaired relative to that of PAX3 despite the two proteins having identical PAX DNA-binding domains. However, the PAX3-FKHR fusion protein was a much more potent transcriptional activator than PAX3 as determined by transient cotransfection assays using e5-CAT reporter plasmids. The PAX3-FKHR protein may function as an oncogenic transcription factor by enhanced activation of normal PAX3 target genes.
Mol Cell Biol 1995 Mar
PMID:The PAX3-FKHR fusion protein created by the t(2;13) translocation in alveolar rhabdomyosarcomas is a more potent transcriptional activator than PAX3. 786 45

The emergence of drug-resistant tumor cells remains a major problem in cancer chemotherapy. Resistance to multiple unrelated antineoplastic drugs may be related, in part, to expression of the P-glycoprotein. The cell line RD, derived from an embryonic rhabdomyosarcoma tumor, was used as an in vitro model to examine the development of drug resistance. A cell line resistant to actinomycin D (RD-DAC) was developed by growing RD in increasing concentrations of the drug. The ID50 (concentration of drug needed to induce a 50% reduction in cell growth) of the resultant line to actinomycin D was more than 15 times that of the parental line. The resistant line was cross-resistant to vincristine and doxorubicin. Resistance to actinomycin D resulted in increased P-glycoprotein expression, which was associated with a change in desmin and vimentin expression. These results suggest that exposure to chemotherapeutic drugs can induce not only classical multidrug resistance, but also a process of cellular differentiation in rhabdomyosarcoma cells.
Cell Mol Biol (Noisy-le-grand) 1994 Mar
PMID:Actinomycin D causes multidrug resistance and differentiation in a human rhabdomyosarcoma cell line. 791 94

Insulin-like growth factor II (IGF-II) is a mitogen for many cell types and an important modulator of muscle growth and differentiation. IGF-II gene is prevalently expressed during prenatal development and its gene activity is regulated by genomic imprinting, in that the allele inherited from the father is active and the allele inherited from the mother is inactive in most normal tissues. IGF-II expression is activated in several types of human neoplasms and an alteration of IGF-II imprinting has been described in Beckwith-Wiedemann syndrome and Wilms' tumor. Here we show that monoallelic expression of IGF-II gene is conserved in normal adult muscle tissue whereas two or more copies of active IGF-II alleles, arising by either relaxation of imprinting or duplication of the active allele, are found in 9 out of 11 (82%) rhabdomyosarcomas retaining heterozygosity at 11p15, regardless of the histological subtype. Since IGF-II has been indicated as an autocrine growth factor for rhabdomyosarcoma cells, these findings strongly suggest that acquisition of a double dosage of active IGF-II gene is an important step for the initiation or progression of rhabdomyosarcoma tumorigenesis. Among different types of muscle tumors, relaxation of imprinting seems to arise prevalently in rhabdomyosarcomas, since we have detected only one case of partial reactivation of the maternal IGF-II allele out of 7 leiomyosarcomas tested.
Hum Mol Genet 1994 Jul
PMID:Mono- and bi-allelic expression of insulin-like growth factor II gene in human muscle tumors. 798 80

BA-Han-1C rat rhabdomyosarcoma cells grow with a transformed phenotype and do not differentiate efficiently. Here, we report that these cells can be induced with pertussis toxin (PTX) to rapidly express the myogenin gene and form terminally differentiated myotubes. Potential targets for the effect mediated by PTX are G alpha i-2 and G alpha i-3 proteins, the only inhibitor GTP-binding proteins expressed in these cells. While G alpha i-2 is found at the plasma membrane, G alpha i-3 is predominantly associated with Golgi vesicles and endoplasmic reticulum, suggesting that it may regulate protein trafficking. Differentiation of BA-Han-1C cells can also be induced by suramin, heparin, and other polyanions. As these compounds bind certain peptide growth factors, we assume that differentiation of BA-Han-1C cells is blocked by pathways involving autocrine or paracrine acting growth stimulating peptides. We present evidence that bFGF and cAMP inhibit induced differentiation in BA-Han-1C cells similar to normal myogenic cell lines, suggesting that signaling pathways mediated by these compounds are unaltered.
Cell Mol Biol Res 1993
PMID:Differentiation of BA-HAN-1C rhabdomyosarcoma cells is controlled by a pertussis toxin sensitive signaling pathway. 829 37

Most rhabdomyosarcomas are poorly differentiated malignant tumors. Dimethyl sulfoxide has been shown to modulate cell differentiation in cultured human cells. We induced differentiation in human rhabdomyosarcoma cell lines A-673, RD and A-204 with 1.25% dimethyl sulfoxide, and used desmin, the protein most frequently used as a marker of muscle cell differentiation, to trace this process. As alternative markers of the degree of differentiation, we quantified the expression of the proteins actin, tropomyosin and alpha-actinin in these cell lines, and followed the changes in expression of these proteins after induction for 8, 12, 24, 48 and 72 hrs. In the process of differentiation, protein expression in both the cytoplasm and cytoskeleton was significantly increased by treatments lasting 12 hrs. (alpha-actinin) and 24 hrs. (actin). On the basis of our results, alpha-actinin can be considered as an earlier marker of differentiation than actin in human rhabdomyosarcoma cell lines. However, the earliest indication of differentiation was a modification in desmin expression (8 hrs.). Because changes in tropomyosin expression were less marked, we consider this protein as a poor marker of rhabdomyosarcoma cell differentiation.
Cell Mol Biol (Noisy-le-grand) 1993 Jul
PMID:Actin, tropomyosin and alpha-actinin as markers of differentiation in human rhabdomyosarcoma cell lines induced with dimethyl sulfoxide. 837 4

The FKHR gene, which contains a forkhead DNA-binding motif, is fused to either PAX3 or PAX7 by the t(2;13) or t(1;13) translocation in alveolar rhabdomyosarcoma,respectively. These tumors express chimeric transcripts encoding the N-terminal portion of either PAX protein fused to the C-terminal portion of FKHR. To understand the structural basis and functional consequences of these translocations, we characterized the wild-type FKHR gene and its rearrangement in alveolar rhabdomyosarcomas. By isolating and analyzing phage, cosmid and YAC clones, we determined that FKHR consists of three exons spanning 140 kb and that several highly similar loci are present in other genomic regions. Exon 1 encodes the N-terminus of the forkhead domain and is embedded within demethylated CpG island. RNA analyses reveal FKHR transcripts initiate from a TATA-less promoter within this island. Exon 2 encodes the C-terminus of the forkhead domain and a transcription activation domain, whereas exon 3 encodes a large 3' untranslated region. The intron 1-exon 2 boundary precisely matches the FHKR fusion point in the chimeric transcripts found in alveolar rhabdomyosarcomas. Using pulsed-field and fluorescence in situ hybridization analyses, we demonstrate that the 130kb FKHR intron 1 is rearranged in t(2;13)-containing alveolar rhabdomyosarcomas. Our findings indicate that FKHR intron 1 provides a large target for DNA rearrangemnt. Rearrangement of this intron with PAX3 produces two important functional consequences: in-frame fusion of N-terminal PAX3 sequences to the FKHR transcriptional activation domain and disruption of the FKHR DNA binding domain.
Hum Mol Genet 1995 Dec
PMID:Structural characterization of the FKHR gene and its rearrangement in alveolar rhabdomyosarcoma. 863 10


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>