Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

For the purpose of clarifying cellular differentiation of epithelioid sarcoma, studies based on various methods were performed. Enzyme histochemical studies showed that epithelioid sarcoma tumor cells have characteristics intermediate between epithelial cells and the large plump cells of synovial sarcoma-incomplete epithelial differentiation. For alkaline phosphatase and adenosine triphosphatase particularly, positive cells and negative cells coexisted, as in the large plump cells of synovial sarcoma. Immunohistochemical studies for alpha 1-antitrypsin, alpha 1-antichymotrypsin, vimentin, and keratin also showed that epithelioid sarcoma tumor cells are very similar to the large plump cells of synovial sarcoma and have incomplete epithelial differentiation. For example, the examinations of serial sections and double staining methods revealed that keratin-positive cells are always vimentin-positive in epithelioid sarcoma and in the monophasic area of synovial sarcoma. Electron-microscopically, bundles of intermediate filaments and filopodia toward the intercellular lumen were observed, as in the monophasic area of synovial sarcoma. The results of enzyme-histochemical and immunohistochemical studies of non-neoplastic synovial lining cells, performed here for the first time, are also discussed.
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PMID:Cellular differentiation of epithelioid sarcoma. An electron-microscopic, enzyme-histochemical, and immunohistochemical study. 258 Apr 43

To determine whether the mononuclear cells (MC) and multinucleated giant cells (GC) of giant cell tumor of tendon sheath (GCTTS) exhibit evidence of monocyte/macrophage lineage, we studied their antigenic features (seven cases, paraffin sections; two cases, frozen sections) and enzymatic features in situ (four cases, plastic sections). Both MC and GC expressed a monocyte/macrophage phenotype: HLA-A,B,C+, HLA-DR+, T200+ (leukocyte common antigen), Leu-M3+ and Leu-3+. MC and GC also expressed similar enzymatic phenotypes which resembled that of osteoclasts. Both were rich in acid phosphatase and contained smaller, variable amounts of ATPase, beta-glucuronidase, alpha-naphthyl acetate esterase, and 5'-nucleotidase. Both lacked alkaline phosphatase. Reactive osteoclasts in plastic and paraffin sections were also T200+, a finding strongly supporting their bone marrow derivation and leukocytic differentiation. In plastic sections, osteoclasts were additionally reactive with macrophage antigen EBM11. In aggregate, these data suggest that GCTTS is a true histiocytic lesion of monocyte/macrophage lineage composed of phenotypically similar MC and GC that most closely resemble osteoclasts. We found no evidence that GCTTS cells resemble osteoblasts, fibroblasts, or synovial sarcoma cells. Furthermore, expression of the Ki-67 nuclear antigen by 1-2% of MC but not by GC suggests that the proliferating cells in GCTTS are restricted to its MC component.
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PMID:The cells of giant cell tumor of tendon sheath resemble osteoclasts. 283 1

A typical case of biphasic synovial sarcoma was studied using enzyme histochemistry. A marked difference between the staining characteristics of the spindle cells and the epithelial-like cells was demonstrated by reactions for various hydrolytic enzymes. The epithelial-like cells exhibited a strong reactivity for alkaline phosphatase, acid phosphatase, adenosine triphosphatase and nonspecific esterase, whereas spindle-cells were completely unreactive when tested for these enzymes. This is, to our knowledge, the first report demonstrating differences in the enzymatic pattern of the two cell populations which compose synovial sarcoma.
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PMID:Synovial sarcoma enzyme histochemistry of a typical case. 629 96

Ninety-one cases of human bone and soft tissue tumours were studied for calcium pump expression by strepto-avidin-biotin immunohistochemical staining with a monoclonal antibody against sarcoplasmic reticulum calcium-ATPase (mAb6F5). Two out of 5 cases of embryonal rhabdomyosarcoma, 1 out of 5 cases of biphasic synovial sarcoma, 4 of 4 cases of chordoma and all of 3 chondrosarcoma cases were positive for mAb6F5. Although this novel monoclonal antibody can be used as a marker of myogenic tumours, the present positive result for endoplasmic reticulum calcium-ATPase (calcium pump) in other tumours including chordoma, chondrosarcoma and synovial sarcoma indicates a wider immunoreactivity. The findings further suggest that intracellular calcium may play an important role in cell proliferation and/or differentiation.
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PMID:Calcium pump expression in human bone and soft tissue tumours. 823 15

The SWI/SNF multisubunit complex modulates chromatin structure through the activity of two mutually exclusive catalytic subunits, SMARCA2 and SMARCA4, which both contain a bromodomain and an ATPase domain. Using RNAi, cancer-specific vulnerabilities have been identified in SWI/SNF-mutant tumors, including SMARCA4-deficient lung cancer; however, the contribution of conserved, druggable protein domains to this anticancer phenotype is unknown. Here, we functionally deconstruct the SMARCA2/4 paralog dependence of cancer cells using bioinformatics, genetic, and pharmacologic tools. We evaluate a selective SMARCA2/4 bromodomain inhibitor (PFI-3) and characterize its activity in chromatin-binding and cell-functional assays focusing on cells with altered SWI/SNF complex (e.g., lung, synovial sarcoma, leukemia, and rhabdoid tumors). We demonstrate that PFI-3 is a potent, cell-permeable probe capable of displacing ectopically expressed, GFP-tagged SMARCA2-bromodomain from chromatin, yet contrary to target knockdown, the inhibitor fails to display an antiproliferative phenotype. Mechanistically, the lack of pharmacologic efficacy is reconciled by the failure of bromodomain inhibition to displace endogenous, full-length SMARCA2 from chromatin as determined by in situ cell extraction, chromatin immunoprecipitation, and target gene expression studies. Furthermore, using inducible RNAi and cDNA complementation (bromodomain- and ATPase-dead constructs), we unequivocally identify the ATPase domain, and not the bromodomain of SMARCA2, as the relevant therapeutic target with the catalytic activity suppressing defined transcriptional programs. Taken together, our complementary genetic and pharmacologic studies exemplify a general strategy for multidomain protein drug-target validation and in case of SMARCA2/4 highlight the potential for drugging the more challenging helicase/ATPase domain to deliver on the promise of synthetic-lethality therapy.
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PMID:The SMARCA2/4 ATPase Domain Surpasses the Bromodomain as a Drug Target in SWI/SNF-Mutant Cancers: Insights from cDNA Rescue and PFI-3 Inhibitor Studies. 2613 43

The sesquiterpene (-)Englerin A (EA) is an organic compound from the plant Phyllanthus engleri which acts via heteromeric TRPC4/C1 channels to cause cytotoxicity in some types of cancer cell but not normal cells. Here we identified selective cytotoxicity of EA in human synovial sarcoma cells (SW982 cells) and investigated the mechanism. EA induced cation channel current (Icat) in SW982 cells with biophysical characteristics of heteromeric TRPC4/C1 channels. Inhibitors of homomeric TRPC4 channels were weak inhibitors of the Icat and EA-induced cytotoxicity whereas a potent inhibitor of TRPC4/C1 channels (Pico145) strongly inhibited Icat and cytotoxicity. Depletion of TRPC1 converted Icat into a current with biophysical and pharmacological properties of homomeric TRPC4 channels and depletion of TRPC1 or TRPC4 suppressed the cytotoxicity of EA. A Na+/K+-ATPase inhibitor (ouabain) potentiated EA-induced cytotoxicity and direct Na+ loading by gramicidin-A caused Pico145-resistant cytotoxicity in the absence of EA. We conclude that EA has a potent cytotoxic effect on human synovial sarcoma cells which is mediated by heteromeric TRPC4/C1 channels and Na+ loading.
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PMID:Na+ entry through heteromeric TRPC4/C1 channels mediates (-)Englerin A-induced cytotoxicity in synovial sarcoma cells. 2920 34