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

Canine cancer is of major significance in terms of animal health and welfare and soft tissue sarcomas are an important group of tumours accounting for approximately 15% of all canine tumours presented. Abnormal p53 protein expression and gene mutations have been identified in a number of different canine tumour types. However, mdm2 gene amplification has only been investigated in a limited number of canine osteosarcomas. In this present study a series of canine soft-tissue sarcomas (STS) were examined for p53 mutations and/or mdm2 amplification. For p53 mutational studies polymerase chain reaction and direct DNA sequencing was used. Gene mutations were identified in 6 of 30 (20%) primary tumour cases including MPNST (n=3) leiomysarcoma (n=1), heamangiosarcoma (n=1) and sarcoma (n=1). mdm2 gene amplification was assessed by Southern Blot. Although there was no evidence for major gene rearrangements, gene amplification was detected in 4 of 35 (11.4 %) primary tumours including MPNST (n=2), rhabdomyosarcoma (n=2). A total of 33 cases were examined for both p53 mutations and mdm2 amplification. Seven of the tumours were positive for p53 mutations, while five were positive for mdm2 amplification. With the exception of one case, a reciprocal relationship between the presence of a p53 mutation and mdm2 gene amplification was demonstrated.
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PMID:Analysis of p53 mutational events and MDM2 amplification in canine soft-tissue sarcomas. 1167 55

The MDM2 protein is known to be overexpressed in some sarcomas including rhabdomyosarcoma. However, the extent to which the MDM2 protein influences sensitivity to chemotherapeutic drugs is unclear. We have analysed this further using stable transfection of the mdm2 gene into 4 well-characterised human paediatric rhabdomyosarcoma cell lines. Transfection with the mdm2 gene resulted in increased levels of the MDM2 protein in all the cell lines. In 2 of the lines, SCMC and RD, the mdm2 gene caused between 2-fold and 61-fold increase in resistance to vincristine, etoposide and doxorubicin but not to cisplatin. In these lines there was an increase in expression of the mdr-1 gene which encodes P-glycoprotein, but not the mrp1 gene which encodes the multidrug resistance protein (MRP). The resistance was reversible using the MDR modulator PSC833, confirming the presence of P-glycoprotein. We conclude that MDM2 overexpression may be a mechanism by which multidrug resistance is regulated in some rhabdomyosarcomas.
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PMID:High levels of the MDM2 oncogene in paediatric rhabdomyosarcoma cell lines may confer multidrug resistance. 1174 97

We evaluated amplification and overrepresentation of CDK4, MDM2, GLI and SAS genes of the 12q13-15 region, in a group of soft tissue sarcomas including leiomyosarcomas (LMS), alveolar rhabdomyosarcomas (ARMS) and embryonal (anaplastic and classic variants) rhabdomyosarcomas (ERMS), to ascertain genomic alterations and possible differences within histologic subtypes of rhabdomyosarcoma (RMS). Quantitative real-time PCR was performed on DNA samples from 29 LMS, 9 ARMS, 7 anaplastic ERMS and 6 classic ERMS. Alteration of one or more of the 12q13-15 genes was revealed in 13/29 LMS (45%) and 12/22 RMS (54%) including 5/9 ARMS (56%), 5/7 anaplastic ERMS (71%) and 2/6 classic ERMS (33%). The potential importance of overproduction of protein products in neoplastic development, led us also to study a possible high expression of cdk4, mdm2 and gli proteins in immunohistochemical staining experiments on paraffin-embedded tissue samples of the same cases. Among LMS and RMS most cases with CDK4, MDM2 and GLI gene alterations also showed a simultaneous high expression of the relative protein. In summary, these results indicate that amplification or overerepresentation of genes at 12q13-15 region involve both LMS and RMS. Moreover these genes alterations reveal predominantly in the alveolar and in the anaplastic variant of the embryonal subtype. These two seem to have a more similar behavior than anaplastic and classic embryonal that are classified in the same subtype.
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PMID:Amplification of CDK4, MDM2, SAS and GLI genes in leiomyosarcoma, alveolar and embryonal rhabdomyosarcoma. 1502 1

Dedifferentiated areas of dedifferentiated liposarcoma (DDL) usually show malignant fibrous histiocytoma (MFH)- or fibrosarcoma-like features and lack any histologic signs of specific differentiation. However, some reports have demonstrated specific differentiation in these areas, with histologic features resembling those of rhabdomyosarcoma, leiomyosarcoma, and osteosarcoma. We report here a pathologic and genetic analysis of three cases of DDLs with rhabdomyosarcomatous areas. MFH- or fibrosarcoma-like areas of one primary DDL and two recurrent DDLs contained various amounts of rhabdomyoblasts, which were immunoreactive for desmin, myoglobin, muscle actin (HHF-35), and myogenin. An ultrastructural examination demonstrated rhabdomyoblasts with abundant cytoplasm containing thin and thick filaments and Z-bands. By real-time PCR, amplification of mdm2 and cdk4 was confirmed in both well-differentiated and dedifferentiated areas with rhabdomyoblasts of all cases. To our knowledge, only seven cases of DDLs with rhabdomyosarcomatous components have been reported, and furthermore, the genetic profiles of the rhabdomyosarcomatous components in DDLs have not been investigated. This study demonstrates that DDLs with rhabdomyosarcomatous areas have genetic alterations that are common to well-differentiated/dedifferentiated liposarcomas.
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PMID:Dedifferentiated liposarcoma with rhabdomyoblastic differentiation. 1601 47

Rhabdomyosarcoma (RMS) is a common soft-tissue sarcoma of childhood in need of more effective therapeutic options. The expression of p53 in RMS is heterogeneous such that some tumors are wild-type whereas others are p53 mutant. The small molecule CP-31398 modulates both the wild-type and the mutant p53 proteins. Here, we show that CP-31398 blocks the growth of RMS cells that have either wild-type or mutant p53 status. In wild-type A204 cells, CP-31398 increased the expression of p53 and its downstream transcriptional targets, p21 and mdm2; enhanced the expression of apoptosis-related proteins; and reduced proliferation biomarkers. Flow profiling of CP-31398-treated cells indicated an enhancement in sub-G(0) and G(1) populations. CP-31398 inhibited proliferation in a manner associated with co-induction of SOX9 and p21. Apoptosis induced by CP-31398 occurred with translocation of p53 to mitochondria, leading to altered mitochondrial membrane potential, cytochrome c release, and reactive oxygen species release. In vivo, CP-31398 decreased the growth of tumor xenografts composed of wild-type or mutant p53 tumor cells, increasing tumor-free host survival. Our findings indicate that the ability of CP-31398 to modulate wild-type and mutant p53 results in the inhibition of RMS growth and invasiveness.
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PMID:Targeting wild-type and mutant p53 with small molecule CP-31398 blocks the growth of rhabdomyosarcoma by inducing reactive oxygen species-dependent apoptosis. 2068