Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood and accounts for 10% of all solid tumors in children. There are three different histologic forms of this tumor: embryonal (RMS-E), alveolar (RMS-A), and primitive (RMS-P). Among these, the embryonal form has responded well to chemotherapy. Identification of the correct subtype is important for both the management and treatment of this malignancy. However, the histopathologic classification of RMS is sometimes difficult and distinguishing between the embryonic and primitive forms can present a diagnostic dilemma. Chromosomal abnormalities have been observed in all subtypes. We present the cytogenetic findings in six cases of RMS or related sarcoma. All four cases with RMS-A had both numerical and structural abnormalities in the tumor and involved bone marrow specimens. Three patients had a common marker, t(2;13)(q37;q14), and one patient had a variant marker involving 13q14, t(1;13) (p36;q14), and double minutes (dmin). The single embryonal RMS patient had modal chromosome numbers in the hypertriploid range and extensive structural abnormalities; the t(2;13) was not present, but translocation of 13q to both 1q and 2p was observed, der(1)t(1;13)(q21;q14) and der(2)t(2;13)(p25;q14). The patient with primitive type RMS had a hypodiploid line with several markers, including a complex translocation involving chromosomes 5 and 13 with a breakpoint at 13q14, and t(11;12)(q24;q12), a chromosome marker heretofore found only in Ewing's sarcoma and related tumors. This patient had atypical RMS with mixed neural and myogenic elements. The significance of these chromosomal markers and their importance in the characterization of childhood tumors are discussed, along with a review of the literature.
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PMID:Cytogenetic studies in subgroups of rhabdomyosarcoma. 128 18

Cytogenetic studies of a rhabdomyosarcoma of mixed embryonal and alveolar histology in an 11-month-old male revealed a single structural abnormality, t(1;13)(p36;q14). This abnormality may define a subset of patients with a variant of the t(2;13)(q35;q14) translocation frequently seen in alveolar rhabdomyosarcoma.
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PMID:Chromosomal translocation t(1;13)(p36;q14) in a case of rhabdomyosarcoma. 166 83

In three cases of alveolar rhabdomyosarcoma with variant translocations, two tumors contained an identical translocation, t(1;13)(p36.1;q14); the third tumor contained a t(8;13)(p21;q14). All three patients were 2 years old, markedly younger than the median age for patients with t(2;13)-positive alveolar rhabdomyosarcoma. The alteration of genetic material on chromosome 13 may be of primary importance in the development of alveolar rhabdomyosarcoma.
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PMID:Variant translocations of chromosome 13 in alveolar rhabdomyosarcoma. 177 15

Although the t(2;13)(q35;q14) translocation has been found in most cases of the pediatric cancer alveolar rhabdomyosarcoma, several cases have been reported with a variant t(1;13)(p36;q14) translocation. Our findings indicate that this t(1;13) rearranges PAX7 on chromosome 1 and fuses it to FKHR on chromosome 13. This fusion results in a chimeric transcript consisting of 5' PAX7 and 3' FKHR regions, which is similar to the 5' PAX3-3' FKHR transcript formed by the t(2;13). The 5' PAX3 and PAX7 regions encode related DNA binding domains, and therefore we postulate that these translocations create similar chimeric transcription factors that alter expression of a common group of target genes.
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PMID:Fusion of PAX7 to FKHR by the variant t(1;13)(p36;q14) translocation in alveolar rhabdomyosarcoma. 818 70

In the pediatric cancer alveolar rhabdomyosarcoma, characteristic t(2;13)(q35;q14) or variant t(1;13)(p36;q14) chromosomal translocations generate PAX3-FKHR or PAX7-FKHR fusion genes. Using fluorescence in situ hybridization, reverse transcriptase-polymerase chain reaction and quantitative Southern blot analyses, we demonstrate that these fusion genes are amplified in 20% of fusion-positive tumors. In particular, we found in vivo amplification of these fusions in one of 22 PAX3-FKHR-positive cases and five of seven PAX7-FKHR-positive cases. These findings indicate that translocation and amplification can occur sequentially in a cancer to alter both the structure and copy number of a gene and thereby activate oncogenic activity by complementary mechanisms.
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PMID:In vivo amplification of the PAX3-FKHR and PAX7-FKHR fusion genes in alveolar rhabdomyosarcoma. 878 35

Chromosomal translocations identified in hematopoietic and solid tumors result in deregulated expression of protooncogenes or creation of chimeric proteins with tumorigenic potential. In the pediatric solid tumor alveolar rhabdomyosarcoma, a consistent t(2;13)(q35;q14) or variant t(1;13)(p36;q14) translocation generates PAX3-FKHR or PAX7-FKHR fusion proteins, respectively. In this report, we demonstrate that in addition to functional alterations these translocations are associated with fusion product overexpression. Furthermore, PAX3-FKHR and PAX7-FKHR overexpression occurs by distinct mechanisms. Transcription of PAX3-FKHR is increased relative to wild-type PAX3 by a copy number-independent process. In contrast, PAX7-FKHR overexpression results from fusion gene amplification. Thus, gene-specific mechanisms were selected to overexpress PAX3-FKHR and PAX7-FKHR in alveolar rhabdomyosarcoma, presumably due to differences in regulation between the wild-type loci. We postulate that these overexpression mechanisms ensure a critical level of gene product for the oncogenic effects of these fusions.
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PMID:Fusion genes resulting from alternative chromosomal translocations are overexpressed by gene-specific mechanisms in alveolar rhabdomyosarcoma. 922 12

During the past two decades we have witnessed the identification of an expanding list of immunohistochemical and molecular markers linked to histopathologically defined subtypes of tumors. These markers offer new insights and approaches to the classification of tumors with important prognostic and/or therapeutic implications. We review the potentially diagnostic immunohistochemical and molecular markers of soft tissue tumors (STTs). The immunohistochemical markers reviewed include vimentin, cytokeratin, desmin, HHF35, S100, myoD1, alpha1-antitrypsin, vascular markers (factor VIII, CD31, CD34), MIC2, and others. The potentially diagnostic chromosomal translocations and associated genes identified in STT include Ewing's/PNET t(11;22)(q24;q12)(FLI1;EWS), t(21;22)(q22;q12)(ERG; EWS); t(7;22)(p22;q12)(ETV1;EWS); desmoplastic small round cell tumor t(11;22)(p13;q12)(WT1;EWS); extraskeletal myxoid chondrosarcoma t(9;22)(q22;q12) (TEC(CHN);EWS); malignant ectomesenchymoma t(11;22)(q24;q12)(FLI1;EWS); alveolar rhabdomyosarcoma t(2;13)(q35;q14)(PAX-3;FKHR); t(1;13) (p36;q14)(PAX-7;FKHR); myxoid and round cell liposarcoma t(12;16)(q13;p11)(CHOP;TLS(FUS)); synovial sarcoma t(X;18)(p11;q11)(SSX1&2;SYT), and others. The nature, utility, and limitations of these markers in diagnostic settings are explored.
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PMID:Immunohistochemical and molecular genetic approaches to soft tissue tumor diagnosis: a primer. 934 17

Although most cases of alveolar rhabdomyosarcoma (RMS) are characterized by the chromosomal translocation t(2;13)(q35;q14), several cases have been reported with a variant t(1;13)(p36;q14). We present the clinical, morphological and cytogenetic features of an alveolar RMS in a 4-year-old boy. Chromosomal analysis revealed a hypertriploid to hypotetraploid karyotype with a t(1;13)(p36;q14) in all tumor cells. It appears that alveolar RMS with t(1;13) occurs in younger children and displays a higher incidence to upper and lower extremity than tumors with t(2;13).
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PMID:Clinical aspects of alveolar rhabdomyosarcoma with translocation t(1;13)(p36;q14) and hypotetraploidy. 1049 Oct 19

Rhabdomyosarcomas are a heterogeneous group of malignant tumors and are the most common soft-tissue sarcoma of childhood. Rhabdomyosarcomas resemble developing skeletal muscle, notably in their expression of the MRF family of transcription factors and the PAX3 and PAX7 genes. These PAX genes are also involved through specific translocations, t(2;13)(q35;q14) and variant t(1;13)(p36;q14) in the alveolar subtype, which result in PAX3-FKHR and PAX7-FKHR fusion genes, respectively. The fusion genes are thought critically to affect downstream targets of PAX3 and PAX7 or possibly have novel targets. Similar downstream changes may also be involved in embryonal and fusion gene negative cases. Genomic amplification of such genes as MYCN, MDM2, CDK4, and PAX7-FKHR is a feature mainly of the alveolar subtype, while specific chromosomal gains, including chromosomes 2, 8, 12, and 13, are associated with the embryonal subtype. Loss of alleles and imprinting at 11p15.5 and disruption of genes such as IGF2, ATR, PTC, P16, and TP53 have also been implicated in rhabdomyosarcoma development. Whereas there is now a realistic possibility of cure in the majority of cases, there remains a subset that is resistant to multimodality therapy, including high-dose chemotherapy. Characterization of the defining molecular features of tumors that are likely to behave aggressively represents a particular challenge. Current research is leading toward a better understanding of rhabdomyosarcoma tumorigenesis, which may ultimately result in novel therapeutic strategies that increase the overall cure. Genes Chromosomes Cancer 26:275-285, 1999.
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PMID:Genes, chromosomes, and rhabdomyosarcoma. 1053 62

Alveolar rhabdomyosarcoma (ARMS) is associated with the specific chromosomal translocation (2;13)(q35;q14) or its rarer variant t(1;13)(p36;q14), which produces the fusion gene PAX7-FKHR. Here we describe the human cell line RC2, derived from an ARMS, which harbors a cryptic t(1;13)(p36;q14) and concomitantly shows amplification of the PAX7-FKHR fusion gene and of the MYCN oncogene. The t(1;13) and MYCN oncogene were studied by standard cytogenetic analysis and molecular techniques. The reverse transcriptase polymerase chain reaction demonstrated the expression of PAX7-FKHR mRNA in RC2 cells, although karyotype analysis failed to demonstrate a t(1;13)(p36;q14) chromosomal translocation or a derivative 13 chromosome. Double minute chromosomes were detected in all the metaphases studied. Fluorescence in situ hybridization analysis revealed multiple copies of the PAX7-FKHR fusion gene localized exclusively on a subset of double minutes, whereas multiple copies of MYCN were identified on other double minute chromosomes. Southern-blot analysis demonstrated that RC2 cells contain approximately 20 copies of the MYCN oncogene. So far no continuous RMS cell line carrying the t(1;13)(p36;q14) has been described, and PAX7-FKHR and MYCN amplifications have always been reported to occur separately in rhabdomyosarcoma (RMS). The availability of an ARMS cell line that harbors the t(1;13)(p36;q14) constitutes a useful tool for further understanding the role of the PAX7-FKHR fusion gene in RMS oncogenesis and may improve knowledge of the possible relation between PAX7-FKHR and MYCN amplification.
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PMID:Concomitant amplification and expression of PAX7-FKHR and MYCN in a human rhabdomyosarcoma cell line carrying a cryptic t(1;13)(p36;q14). 1106 97


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