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

Bcr-abl mRNA expression was studied in patients with chronic myeloproliferative disorders (CMPD) by the reverse transcriptase-polymerase chain reaction (RT-PCR) method. A bcr-abl transcript was not found in any patient with polycythemia vera, essential thrombocythemia or primary myelofibrosis, suggesting that the bcr-abl rearranged clone is not present in CMPD other than chronic myelogenous leukemia (CML). In CML clinical and laboratory data were compared from three bcr-abl types: the bcr exon 2-abl exon 2 (B2-A2) type, bcr exon 3-abl exon 2 (B3-A2) type and the co-expression type. Age at diagnosis tended to be younger (p = 0.08) in the co-expression type, and the platelet count tended to be lower (p = 0.11) in the B2-A2 type. However, there was no difference in other data, including the duration of the chronic phase and the phenotype of blasts at blast crisis.
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PMID:Bcr-abl mRNA expression in patients with chronic myeloproliferative disorders--absence of bcr-abl fused clone except chronic myelocytic leukemia. 825

Idiopathic hypereosinophilic syndrome (IHES) is a disease that is difficult to classify, and diagnosis is one of exclusion. The identification of a cytogenetically invisible interstitial deletion resulting in the fusion of FIP1-Like-1 (FIP1L1) to platelet-derived growth factor receptor alpha (PDGFRA) has enabled many IHES cases to be reclassified as chronic eosinophilic leukemia. As it is likely that PDGFRA may fuse to other partner genes, we established a reverse transcriptase-PCR test to detect specific overexpression of the PDGFRA kinase domain as an indicator of the presence of a fusion gene. Overexpression was detected in 12/12 FIP1L1-PDGFRA-positive patients, plus 9/217 (4%) patients with hypereosinophilia who had tested negative for FIP1L1-PDGFRA. One of the positive cases was investigated in detail and found to have a complex karyotype involving chromosomes 3, 4 and 10. Amplification of the genomic breakpoint by bubble PCR revealed a novel fusion between KIF5B at 10p11 and PDGFRA at 4q12. Imatinib, a known inhibitor of PDGFRalpha, produced a complete cytogenetic response and disappearance of the KIF5B-PDGFRA fusion by PCR, from both genomic DNA and mRNA. This study demonstrates the utility of screening for PDGFRA kinase domain overexpression in patients with IHES and has identified a third PDGFRA fusion partner in chronic myeloproliferative disorders.
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PMID:Identification of a novel imatinib responsive KIF5B-PDGFRA fusion gene following screening for PDGFRA overexpression in patients with hypereosinophilia. 1649 88

Fusion genes derived from the platelet-derived growth factor receptor beta (PDGFRB) or alpha (PDGFRA) play an important role in the pathogenesis of BCR-ABL-negative chronic myeloproliferative disorders (CMPDs). These fusion genes encode constitutively activated receptor tyrosine kinases that can be inhibited by imatinib. Twelve patients with BCR-ABL-negative CMPDs and reciprocal translocations involving PDGFRB received imatinib for a median of 47 months (range, 0.1-60 months). Eleven had prompt responses with normalization of peripheral-blood cell counts and disappearance of eosinophilia; 10 had complete resolution of cytogenetic abnormalities and decrease or disappearance of fusion transcripts as measured by reverse transcriptase-polymerase chain reaction (RT-PCR). Updates were sought from 8 further patients previously described in the literature; prompt responses were described in 7 and persist in 6. Our data show that durable hematologic and cytogenetic responses are achieved with imatinib in patients with PDGFRB fusion-positive, BCR-ABL-negative CMPDs.
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PMID:Durable responses to imatinib in patients with PDGFRB fusion gene-positive and BCR-ABL-negative chronic myeloproliferative disorders. 1696 Jan 51

The small molecule CCR5 inhibitors are a new class of drugs for treating infection by human immunodeficiency virus type 1 (HIV-1). They act by binding to the CCR5 co-receptor and preventing its use during HIV-1-cell fusion. Escape mutants can be raised against CCR5 inhibitors in vitro and will arise when these drugs are used clinically. Here, we have assessed the responses of CCR5 inhibitor-resistant viruses to other anti-retroviral drugs that act by different mechanisms, and their sensitivities to neutralizing antibodies (NAbs). The rationale for the latter study is that the resistance pathway for CCR5 inhibitors involves changes in the HIV-1 envelope glycoproteins (Env), which are also targets for NAbs. The escape mutants CC101.19 and D1/85.16 were selected for resistance to AD101 and vicriviroc (VVC), respectively, from the primary R5 HIV-1 isolate CC1/85. Each escape mutant was cross-resistant to other small molecule CCR5 inhibitors (aplaviroc, maraviroc, VVC, AD101 and CMPD 167), but sensitive to protein ligands of CCR5: the modified chemokine PSC-RANTES and the humanized MAb PRO-140. The resistant viruses also retained wild-type sensitivity to the nucleoside reverse transcriptase inhibitor (RTI) zidovudine, the non-nucleoside RTI nevirapine, the protease inhibitor atazanavir and other attachment and fusion inhibitors that act independently of CCR5 (BMS-806, PRO-542 and enfuvirtide). Of note is that the escape mutants were more sensitive than the parental CC1/85 isolate to a subset of neutralizing monoclonal antibodies and to some sera from HIV-1-infected people, implying that sequence changes in Env that confer resistance to CCR5 inhibitors can increase the accessibility of some NAb epitopes. The need to preserve NAb resistance may therefore be a constraint upon how escape from CCR5 inhibitors occurs in vivo.
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PMID:Neutralizing antibody and anti-retroviral drug sensitivities of HIV-1 isolates resistant to small molecule CCR5 inhibitors. 1851 43