Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mitochondrial dysfunction plays a crucial role in cell types that exhibit necrosis-like death after activation of their death program. Tumour necrosis factor (TNF) induces abnormal, perinuclear clustering of mitochondria from an evenly spread distribution throughout the cytoplasm. The mitochondria withdraw from the cell periphery and aggregate in a unipolar perinuclear cluster. TNF-induced mitochondrial clustering is caused by impaired kinesin-mediated transportation of mitochondria. In this report, we describe a novel activity of menadione (MEN), namely the induction of an altered spatial distribution of mitochondria in the choriocarcinoma JAR cells. Strikingly, 2 hours of cell exposition to menadione did not disrupt the integrity of the plasma membrane, while the intracellular ATP level significantly decreased. Control (untreated) cells displayed a typically scattered distribution of filamentary mitochondria inside the cell. After 2 hours of MEN treatment the spatial distribution of the mitochondria was markedly altered to an asymmetric perinuclear clustered distribution. Menadione-stressed cells displayed a highly asymmetrical perinuclear clustered distribution of the mitochondria. The exposure of cells to MEN also results in a change in shape of the mitochondria into a population of enlarged granular structures. The results of our study demonstrate that in JAR cells menadione causes mitochondria to translocate from the cell periphery into the perinuclear region several hours before disruption of cell membrane integrity and cell death.
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PMID:Fast perinuclear clustering of mitochondria in oxidatively stressed human choriocarcinoma cells. 1571 35

The behavior of atypical fibroxanthoma is benign, if strict diagnostic criteria are applied. Tumors with similar pathologic features but deep subcutaneous invasion, necrosis, and/or lymphovascular or perineural invasion are thought to be associated with adverse outcome and are better regarded as pleomorphic dermal sarcoma or undifferentiated pleomorphic sarcoma of skin. This tumor group is not well documented in the literature, and its characteristics are only poorly defined. To study the clinical and pathologic spectrum more comprehensively, we retrieved 32 pleomorphic dermal sarcomas from our departmental files. The tumors were large (median: 25 mm) and exclusively presented on sun-damaged skin with a strong predilection for the head. Typically, elderly men were affected (median age: 81 y). Histologically, these often ulcerated tumors were poorly marginated, asymmetrical, and deeply invasive into deep subcutaneous, muscular, and/or fascial tissues. The tumors were cellular and composed of pleomorphic epithelioid cells, atypical spindle cells, and multinucleated tumor giant cells in varying proportions. Mitotic count was brisk and often atypical. Tumor necrosis was observed in 53%, lymphovascular invasion in 26%, and perineural infiltration in 29%. The majority of tumors showed a predominance of atypical spindle cells in a fascicular arrangement. A sheet-like growth of pleomorphic epithelioid cells or mixed spindle and epithelioid cell features were less frequently observed. Myxoid and keloidal change, a desmoplastic stromal response, pseudoangiomatous and storiform growth patterns, and admixed osteoclast-like giant cells were additional morphologic features in some cases. No immunoreactivity was noted for multiple cytokeratins, S100, HMB-45, desmin, and CD34. Smooth muscle actin was expressed in 70%, CD31 in 48%, epithelial membrane antigen in 16%, Melan A in 6%, and p63 in 1 case. CD10 was expressed in all cases stained. Follow-up (available for 29 patients; median: 24 mo) showed local recurrence in 28% and a metastatic rate of 10%, mainly in the skin. Progressive metastatic disease was observed in 2 patients. Remission was achieved in 1 patient using systemic chemotherapy. The second patient died in the setting of advanced-stage non-Hodgkin lymphoma. No disease-related mortality was noted. Our data underscore the importance of recognizing adverse histologic features in tumors otherwise resembling atypical fibroxanthoma. Deep subcutaneous invasion, tumor necrosis, and perineural and/or lymphovascular invasion confers at least low-grade malignant potential.
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PMID:Pleomorphic dermal sarcoma: adverse histologic features predict aggressive behavior and allow distinction from atypical fibroxanthoma. 2251 Jul 60

Tumour necrosis factor (TNF) is a cytokine belonging to a family of trimeric proteins; it has been shown to be a key mediator in autoimmune diseases such as rheumatoid arthritis and Crohn's disease. While TNF is the target of several successful biologic drugs, attempts to design small molecule therapies directed to this cytokine have not led to approved products. Here we report the discovery of potent small molecule inhibitors of TNF that stabilise an asymmetrical form of the soluble TNF trimer, compromising signalling and inhibiting the functions of TNF in vitro and in vivo. This discovery paves the way for a class of small molecule drugs capable of modulating TNF function by stabilising a naturally sampled, receptor-incompetent conformation of TNF. Furthermore, this approach may prove to be a more general mechanism for inhibiting protein-protein interactions.
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PMID:Small molecules that inhibit TNF signalling by stabilising an asymmetric form of the trimer. 3206 Apr 26