Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.7.7.49 (reverse transcriptase)
31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 7-year-old girl was hospitalized because of a tumorous mass in her left periorbital region. The tumor was removed by local excision. The soft-part tumor recurred in the parotid gland region 4 months later, and a second recurrence was noted on the left side of the neck 3 years and 3 months thereafter. The patient had not received chemotherapy or local irradiation. Histological and immunohistochemical examinations of the recurrent masses revealed morphological characteristics of small cell proliferation with desmoplastic stroma that were similar to those of the initial tumor. The cellular components showed immunoreactivity for desmin, cytokeratin, vimentin, and epithelial membrane antigen in part, but the cells were negative for myogenin, CD99, and neuron-specific enolase. These findings suggested a diagnosis of desmoplastic small cell tumor, despite its extra-abdominal location. The histological diagnosis was confirmed by reverse transcriptase polymerase chain reaction, which demonstrated an EWS-WT1 chimeric fusion gene. An in-frame fusion of EWS exon 9 and WT1 exon 8 was subsequently identified by cloning and sequencing. The chimeric fusion gene might be related to the tissue-specific phenotype of desmoplastic small cell tumors, although further investigation of this speculation is necessary.
...
PMID:Desmoplastic small cell tumor of soft tissue: molecular variant of EWS-WT1 chimeric fusion. 1693 Mar 35

The Wilms' tumor suppressor gene (WT1) encodes a zinc finger transcription factor that is vital during development of several organs including metanephric kidneys. Despite the critical regulatory role of WT1, the pathways and mechanisms by which WT1 orchestrates development remain elusive. To identify WT1 target genes, we performed a genome-wide expression profiling analysis in cells expressing inducible WT1. We identified a number of direct WT1 target genes, including the epidermal growth factor (EGF)-family ligands epiregulin and HB-EGF, the chemokine CX3CL1, and the transcription factors SLUG and JUNB. The target genes were validated using quantitative reverse transcriptase-polymerase chain reaction, small interfering RNA knockdowns, chromatin immunoprecipitation, and luciferase reporter analyses. Immunohistochemistry of fetal kidneys confirmed that a number of the WT1 target genes had overlapping expression patterns with the highly restricted spatiotemporal expression of WT1. Finally, using an in vitro embryonic kidney culture assay, we found that the addition of recombinant epiregulin, amphiregulin, CX3CL1, and interleukin-11 significantly enhanced ureteric bud branching morphogenesis. Our genome-wide screen implicates WT1 in the transcriptional regulation of the EGF-family of growth factors as well as the CX3CL1 chemokine during nephrogenesis.
...
PMID:Identification of novel Wilms' tumor suppressor gene target genes implicated in kidney development. 1743 Aug 90

The study was aimed to explore the NF-kappaB continual activity and the expression of WT1 and MDR1 in acute non-lymphocytic leukemia (ANLL) patients, and to investigate if the three factors affect the curative effect of ANLL together as to provide some theoretical basis for finding new measures to improve the curative effect of refractory ANLL. The bone marrow samples of 45 ANLL patients was collected. 45 patients including 20 primary ANLL patients (A group) and 25 refractory ANLL patients. Refractory ANLL patients were divided into 2 sub-groups (B, C groups). The primary patients who was no effect after more than two courses of treatment were taken as group B, and the patients with more than two relapses were taken as group C. At the same time, 15 patients with simple iron deficiency anemia were collected as negative control. The NF-kappaB continual activity was measured by using electrophoretic mobility shift assay (EMSA) and the expressions of WT1, MDR1 were detected by reverse transcriptase polymerase chain reaction (RT-PCR). The results showed that the activity of NF-kappaB and the expressions of WT1, MDR1 were not detected in 15 samples of simply iron deficiency anemia subjects. The NF-kappaB continual activity, the expression levels of WT1 and MDR1 in the refractory group were significantly higher than that in primary group (P<0.001). But the NF-kappaB continual activity, the expression of WT1 gene and MDR1 gene were not significantly different between group B and group C (P>0.05). By assaying the relativity between the them the NF-kappaB continual activity and the expression of WT1 or MDR1 had positive correlation in ANLL patients. It is concluded that the NF-kappaB continual activity, the overexpression of WT1 and MDR1 may be one of the reasons causing poor curative effect in acute non-lymphocytic leukemia. The NF-kappaB continual activity and the expression of WT1, MDR1, all show positive correlation in ANLL patients.
...
PMID:[Clinical significance of NF-kappaB continual activity and expression of WT1 and MDR1 in acute nonlymphocytic leukemia]. 1749 26

We report 20 cases of a distinct, previously unrecognized renal neoplasm, anaplastic sarcoma of the kidney with polyphenotypic features. The tumors were identified by re-reviewing tumors with unusual anaplastic features from the National Wilms Tumor Study Pathology Center, the International Society of Pediatric Oncology and the United Kingdom Children's Cancer Study Group trials. Patients ranged in age from 10 months to 41 years (median age 5 y, mean age 12 y) and females predominated (1.5:1). Twelve tumors presented in the right kidney, and 5 in the left (laterality was unknown in 3 cases). The most common presentation was a renal mass. Grossly, most tumors were large, measured 4 to 21 cm (mean 12.7 cm) and weighed 115 to 1820 g (mean 835 g). Seven out of 12 tumors suitable for assessment had a distinct cystic component. The tumors involved the pelvi-calyceal system in 5 of the cases. Histologically, all tumors showed a spindle cell component which contained either multiple foci or diffuse, widespread anaplastic changes with bizarre pleomorphic cells and very atypical mitotic figures. Chondroid differentiation was seen in 16 cases, usually in the form of islands of hyaline cartilage (13 cases) or chondroid matrix (3 cases). The nodules of cartilage showed both benign and malignant features, often within the same tumor. In 2 cases small foci of osteoid were found whereas osteoclast-like giant cells were seen in 4 cases. Only 3 of the tumors exhibited a primitive blastema-like area. No neoplastic epithelial structures were identified. No nephrogenic rests were found. Limited immunohistochemical studies showed vimentin positivity in 5/5 cases, desmin was positive in 4/6 cases, MYF4 showed focal weak nuclear positivity in 1/4 cases, but MyoD1 was negative in all cases (0/5). PGP9.5 was focally, strongly positive in 4/5 cases and p53 was strongly positive in 3/6 cases. Cytokeratin, using the antibody CAM5.2, was uniformly negative within the tumor cells. Finally, CD56 was focally positive in 1/6 tumors, whereas all other markers were negative including NB84a (4/4), CD34 (5/6), CD99 (5/5), and WT1 (6/6 cases). In 4 tumors reverse transcriptase-polymerase chain reaction was performed to detect the SYT-SSX fusion transcript produced by the t(x;18), and the ETV6-NTRK3 fusion transcript using RNA extracted from archived paraffin blocks-results were negative in all 4 specimens. Tumor stage was known in 15 patients including 7 stage I, 4 stage II, 3 stage III, and 1 stage IV tumors. They were usually diagnosed as anaplastic Wilms tumors and treated accordingly. Of the 13 patients with a minimum of 2 years follow-up, 4 patients developed distant metastases and 1 had local recurrence including 1 patient with stage IV, 2 with stage III, and 2 with stage I at presentation. Three of them died and 2 were lost to follow-up. One patient with stage I tumor developed widespread metastases and died. Another stage I patient developed local recurrence after 3 months of diagnosis, but was lost to follow-up. Five stage I patients were alive and free of tumor at last follow-up. The most common sites of metastases were lung (3 cases), and liver and bones (2 cases each). These tumors showed pathologic features similar to the pleuropulmonary blastoma of childhood and undifferentiated (embryonal) sarcoma of the liver. In the differential diagnosis, anaplastic Wilms tumor, primary renal synovial sarcoma, malignant mesenchymoma, ectomesenchymoma, and mesenchymal chondrosarcomas have been considered but none of these tumors shared the same features as the 20 cases described here which represent a distinct clinicopathologic entity with morphologic features of a polyphenotypic anaplastic sarcoma of the kidney. Further molecular studies are needed to better understand its nature and more accurate classification.
...
PMID:Anaplastic sarcoma of the kidney: a clinicopathologic study of 20 cases of a new entity with polyphenotypic features. 1789 46

Desmoplastic small round cell tumor is a rare aggressive neoplasm, often presenting in young adult males. Although the classic features are well described, considerable clinical, pathologic, and immunohistochemical variation has been reported. The defining feature is a reciprocal translocation, t(11;22)(p13;q12), which fuses EWS on chromosome 22 to WT1 on chromosome 11. WT1 immunohistochemistry is reportedly useful in distinguishing desmoplastic small round cell tumor from other tumors. Herein, we describe a desmoplastic small round cell tumor of soft tissue with an unusual pattern of WT1 expression associated with a novel variant EWS-WT1 fusion transcript. We compare WT1 expression pattern with 5 intra-abdominal desmoplastic small round cell tumors and review the literature on WT1 expression and variant transcripts in desmoplastic small round cell tumor. Immunohistochemistry for the N- and C-terminals of WT1 was performed in 6 desmoplastic small round cell tumors. The EWS-WT1 fusion transcript was confirmed in all cases by reverse transcriptase polymerase chain reaction. Sequencing of fusion transcripts and reverse transcriptase polymerase chain reaction for wild-type WT1 was performed in 4 cases. The soft tissue desmoplastic small round cell tumor was negative for the WT1 C-terminal and showed nuclear staining with the N-terminal antibody. This case demonstrated 2 novel fusion transcripts, both lacking WT1 exons 9 and 10 and one containing additional exons of WT1 (exons 3-7). This tumor also strongly expressed full-length WT1. Five intra-abdominal desmoplastic small round cell tumors showed nuclear staining for WT1 C-terminal, but not for the N-terminal antibody. Although WT1 immunohistochemistry reflects the EWS-WT1 fusion transcript in most desmoplastic small round cell tumors, some cases express full-length WT1 or have variant transcripts, resulting in atypical staining patterns. Hence, interpretation of WT1 immunostaining requires knowledge of antibody target epitopes and correlation with clinical, morphological, and molecular genetic findings for establishing a diagnosis of desmoplastic small round cell tumor.
...
PMID:A new molecular variant of desmoplastic small round cell tumor: significance of WT1 immunostaining in this entity. 1870 17

A standardized, sensitive and universal method for minimal residual disease (MRD) detection in acute myeloid leukemia (AML) is still pending. Although hyperexpression of Wilms' tumor (WT1) gene transcript has been frequently proposed as an MRD marker in AML, wide comparability of the various methods used for evaluating WT1 expression has not been given. We established and standardized a multicenter approach for quantifying WT1 expression by quantitative reverse transcriptase PCR (qRT-PCR), on the basis of a primer/probe set combination at exons 6 and 7. In a series of quality-control rounds, we analyzed 69 childhood AML samples and 47 normal bone marrow (BM) samples from 4 participating centers. Differences in the individual WT1 expressions levels ranged within <0.5 log of the mean in 82% of the cases. In AML samples, the median WT1/1E+04 Abelson (ABL) expression was 3.5E+03 compared with that of 2.3E+01 in healthy BM samples. As 11.5% of childhood AML samples in this cohort harbored WT1 mutations in exon 7, the effect of mutations on WT1 expression has been investigated, showing that mutated cases expressed significantly higher WT1 levels than wild-type cases. Hence, our approach showed high reproducibility and applicability, even in patients with WT1 mutations; therefore, it can be widely used for the quantitation of WT1 expression in future clinical trials.
...
PMID:Standardization of WT1 mRNA quantitation for minimal residual disease monitoring in childhood AML and implications of WT1 gene mutations: a European multicenter study. 1932 6

Real-time quantitative reverse transcriptase polymerase chain reaction method was established for detecting the expression levels of WT1 gene and WT1+17AA isoforms in 226 acute myeloid leukemia (AML) bone marrow (BM) cells. The results showed that WT1 gene was 2-3 logarithms expressed more in AML BM cells at initial diagnosis or relapse than in normal BM cells (p<0.001), with predominant WT1+17AA isoforms expression (the ratio of WT1+17AA/WT1 more than 0.50). Interestingly the ratio of WT1+17AA/WT1 was statistically higher in relapsed AMLs than in initially diagnosed (p=0.01), speculating that WT1+17AA isoforms might participate in AML relapse.
...
PMID:High expression of WT1 gene in acute myeloid leukemias with more predominant WT1+17AA isoforms at relapse. 1941 92

We evaluated the feasibility and usefulness of reverse transcriptase-polymerase chain reaction (RT-PCR) on fine-needle aspirates for categorization of small blue round cell tumors (SBRCTs). A total of 51 cases, including 25 Ewing sarcoma/peripheral primitive neuroectodermal tumors (PNETs), 11 rhabdomyosarcomas, 13 neuroblastomas, and 2 desmoplastic small round cell tumors (DSRCTs) were analyzed. The detection of the EWS-FLI1 (20/25) and EWS-ERG (4/25) fusion transcripts resolved 24 of 25 cases of Ewing sarcoma/PNET. The PAX3/7-FKHR fusion transcript was detected in 2 of 4 cases of alveolar rhabdomyosarcoma and the EWS-WT1 transcript in both cases of DSRCT. Tyrosine hydroxylase and 3,4-dihydroxyphenylalanine (dopa) decarboxylase transcripts were demonstrated in 10 of 13 cases of neuroblastoma. In comparison, immunocytochemical analysis resolved 19 (76%) of 25 Ewing sarcomas, 9 (82%) of 11 rhabdomyosarcomas, 6 (46%) of 13 neuroblastomas, and 1 (50%) of 2 DSRCTs. Overall, RT-PCR resolved 38 (86%) of 44 vs 35 (69%) of 51 cases by immunocytochemical analysis. RT-PCR is easily applied to fine-needle aspirates of SBRCT and greatly facilitates accurate tumor typing.
...
PMID:Reverse transcriptase-polymerase chain reaction as an ancillary molecular technique in the diagnosis of small blue round cell tumors by fine-needle aspiration cytology. 2023 17

Recent studies have shown that high BAALC expression predicts an adverse prognosis and may define an important risk factor in acute myeloid leukemia patients with normal karyotype. We performed, using real-time quantitative reverse transcriptase polymerase chain reaction (RQ-PCR), the molecular analysis of BAALC gene as a possible minimal residual disease (MRD) marker in 45 patients with newly diagnosed acute leukemia. BAALC transcript levels in 32 patients with CD34 expressed in leukemic blasts were 2-3 logs higher than background levels, and the copy number was reduced in patients achieving hematological remission. Comparative monitoring of MRD by RQ-PCR for the Wilms' tumor gene 1(WT1) or specific translocation markers demonstrated that BAALC had similar kinetics as WT1, AML1/ETO and minor BCR/ABL, but not PML/RARA. Quantitation of BAALC gene expression made it possible to assess MRD in patients with CD34-positive acute leukemia. To our knowledge, this is the first report concerning the use of BAALC mRNA expression for MRD monitoring.
...
PMID:Molecular monitoring of BAALC expression in patients with CD34-positive acute leukemia. 2037 83

Desmoplastic small round cell tumor is a rare malignant neoplasm mostly occurring in the vicinity of or within the peritoneal cavity, and is uncommon in the head and neck region. Tumor location within a major salivary gland is exceptional. We report a case of a 41-year-old Chinese man with a history of diabetes mellitus and end-stage renal failure on peritoneal dialysis with a desmoplastic small round cell tumor occurring in the left submandibular gland. Fine-needle aspiration cytology showed variably cohesive clusters of small cells with hyperchromatic nuclei and fine granular chromatin. On histology the neoplasm displayed classic features of a desmoplastic small round cell tumor with angulated nests of small round blue cells in a fibromyxoid/desmoplastic stroma. Neoplastic cells were immunoreactive for cytokeratins (AE1/3), desmin (paranuclear dot-like), WT-1 (nuclear), epithelial membrane antigen, and CD56. EWS gene translocation and EWS-WT1 gene fusion were detected by fluorescence in situ hybridization and reverse transcriptase polymerase chain reaction, respectively. The case presented is the sixth case of and the oldest reported patient with a desmoplastic small round cell tumor occurring in a major salivary gland to date. Desmoplastic small round cell tumor should be considered in the differential diagnosis of a salivary gland neoplasm with a basaloid or small cell pattern on fine-needle aspiration cytology.
...
PMID:Desmoplastic small round cell tumor of major salivary glands: report of 1 case and a review of the literature. 2086 91


<< Previous 1 2 3 4 5 Next >>

---