Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chimeric transcript SYT-SSX is generated as a result of reciprocal translocation t(X;18), which is the primary cytogenetic abnormality found in, and appears to be specific for, synovial sarcoma. We performed a reverse transcriptase-polymerase chain reaction (RT-PCR) for SYT-SSX transcripts in a series of 84 tumors (61 soft tissue tumors and 23 bone tumors), including a variety of histologic types, to assess its usefulness in molecular diagnosis. Ten synovial sarcomas, three tumors initially unclassified, and one malignant peripheral nerve sheath tumor contained the chimeric transcripts. A review of the original slides and additional examination showed that a diagnosis of synovial sarcoma was appropriate for these cases. Additionally, in situ hybridization with an SSX1 probe indicated that the chimeric transcripts exist not only in the cells of special components but also in cells showing a variety of histologic patterns. Therefore, RT-PCR can be considered a useful molecular biological technique that can provide objective evidence for diagnosis of synovial sarcoma. Northern blot analysis with an SSX1 probe also detected chimeric SYT-SSX transcripts in the synovial sarcoma cases. The additional smaller bands, however, were also detected in six peripheral primitive neuroectodermal tumors (pPNETs) and one embryonal rhabdomyosarcoma. In five of these pPNETs, other bands ranging in size from 2.0 to 2.2 kb were also found, and it seems possible that these bands might represent novel karyotypic aberrations and/or splicing variants of SSX.
 ...
PMID:Diagnosis of synovial sarcoma with the reverse transcriptase-polymerase chain reaction: analyses of 84 soft tissue and bone tumors. 978 9

Rhabdomyosarcoma may be divided into three subtypes--embryonal, alveolar, and undifferentiated sarcoma--which can be distinguished by molecular analysis. The authors applied reverse transcriptase-polymerase chain reaction analysis (RT-PCR) to analyze tumor samples from 14 children with rhabdomyosarcoma for the presence of the chimeric PAX3-FKHR transcript resulting from the translocation t(2;13)(q35,q14). Both fresh and paraffin-embedded tissues were used. In only nine specimens was the RNA intact for the analysis. The chimeric transcript was identified in seven samples: four alveolar type, one embryonal type, and two undifferentiated sarcoma. Histologic review was performed in the three samples with discordance between the molecular and histologic findings. A sample from a patient with a diagnosis of embryonal rhabdomyosarcoma on presentation and expression of PAX3-FKHR fusion transcript yielded a small focus of alveolar rhabdomyosarcoma and was reclassified as alveolar rhabdomyosarcoma. One of the samples from a patient with undifferentiated sarcoma was redefined as alveolar subtype; the diagnosis of the second undifferentiated sarcoma remained unchanged, in accordance with the histologic diagnosis. These findings further support the recommendation that molecular analysis be included in the diagnostic workup of childhood small round cell tumors to reach a more accurate diagnosis for tailoring of specific treatment.
 ...
PMID:Clinical relevance of molecular diagnosis in childhood rhabdomyosarcoma. 1071 7

Embryonal rhabdomyosarcoma (ERMS) is the most common subtype of RMS that predominantly involves the genitourinary tract and the head and neck regions in children younger than 10 years of age. Cytogenetically, ERMS is most frequently hyperdiploid, with extra copies of chromosomes 2, 7, 8, 11, 12, 13, and 20. No consistent structural chromosomal alteration has been identified in ERMS. In contrast, a t(2;13)(q35;q14) or t(1;13)(q36;q14) corresponding to PAX3-FOXO1A (previously FKHR) and PAX7-FOXO1A gene fusions are considered tumor-specific anomalies for alveolar RMS (ARMS). Occasionally, a recurrent secondary structural rearrangement involving chromosomes 1 and 16 is seen in translocation-positive ARMS, a der(16)t(1;16) resulting in an imbalance of 1q and 16q material. Conventional cytogenetic analysis of an ERMS arising in the urinary bladder of a 22-month-old male child revealed this nonrandom secondary chromosomal aberration, der(16)(1;16)(q22;q24), in a hyperdiploid complement with extra copies of chromosomes 2, 7, 8, 10, 12, 13, 19, and 20. Subsequent analyses showed tumor cells to be negative for FOXO1A, PAX3, or PAX7 gene locus rearrangements (by fluorescence in situ hybridization) and also negative for PAX3-FOXO1A and PAX7-FOXO1A fusion transcripts (by reverse transcriptase-polymerase chain reaction). These results suggest that the unbalanced t(1;16) translocation may be seen in RMSs lacking a primary genetic rearrangement.
 ...
PMID:Embryonal rhabdomyosarcoma with a der(16)t(1;16) translocation. 1735 Apr 70