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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinicopathological and immunohistochemical features of 91 patients with adrenal cortical carcinoma (ACC) are presented. This series included 52 men and 39 women with a mean age of 45.7 years. According to the extent of cellular pleomorphism, it was possible to define ACC as Grade 1, 2 or 3. There was a correlation between the grading and mitotic activity (P less than 0.05). Median survival of patients with G2 or G3 tumors was only 4.3 months, while that of patients with G1 tumors was 24.3 months (P less than 0.05). The histological grading of ACC was thus shown to be an important prognostic factor. In most cases of ACC, silver impregnation demonstrated zona fasciculata-like structures. Immunohistochemically, vimentin-positive tumor cells could be detected in 41 of 56 cases (73.2%) of ACC, while only 6 of 43 cases (14.0%) of adrenal cortical adenoma showed scattered vimentin-positive cells (p less than 0.01). Considering the fact that the adrenal cortex is of mesodermal origin, this finding may suggest dedifferentiation of the tumor to fetal tissue. Twenty-four of 62 cases of ACC showed cytokeratin-positive cells. Vimentin and silver staining are useful for the diagnostic differentiation of ACC from other carcinomas. In the present study, there was no histologic differentiation between clinically functional and nonfunctional ACC.
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PMID:Adrenal cortical carcinoma. A clinicopathological and immunohistochemical study of 91 autopsy cases. 338 47

To study the expression of two different subclasses of intermediate filaments in ethylnitrosourea-induced rat cerebral gliomas, the number of cells immunopositive for each subunit protein, vimentin and astroprotein (GFAP), was quantitatively analyzed. Vimentin is a subunit protein of non-specific intermediate filaments which appear transiently in immature glial cells, while astroprotein (GFAP) is a subunit protein of glial filaments, normally expressed in mature astrocytes. Although most normal astrocytes were negative for vimentin, many tumor cells showed weak to strong immunoreaction for vimentin. The expression of vimentin was more frequent and intense in anaplastic forms of gliomas than in benign forms. Accordingly, the vimentin/GFAP ratio [the number of vimentin-positive cells divided by the number of astroprotein (GFAP)-positive cells] was increased from 0.23 to 1.86, and from 0.26 to 1.85, respectively, as oligodendrogliomas and mixed gliomas become anaplastic. The present study demonstrated that the immunohistochemical study for those two subclasses of intermediate filaments can provide important informations on the cell biological nature of glial tumors.
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PMID:Intermediate filaments and anaplastic change of ENU-induced gliomass: immunohistochemical study with vimentin and astroprotein (GFAP). 344 Aug 78

Vimentin, desmin, glial fibrillary acidic protein, neurofilament triplet proteins, and a mixture of cytokeratins were digested with Ca2+-activated neutral thiol proteinase isolated from Ehrlich ascites tumor (EAT) cells and porcine kidney. All intermediate filament proteins were degraded by the proteinase, although with different rates and Ca2+ optima. These results are in part at variance with our previous statement that the Ca2+-activated proteinase from EAT cells is specific for vimentin and desmin.
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PMID:Efficient degradation in vitro of all intermediate filament subunit proteins by the Ca2+-activated neutral thiol proteinase from Ehrlich ascites tumor cells and porcine kidney. 351 36

Mouse myeloma cells (MPC-11 cell line) known to lack intermediate filaments were treated with the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA). Asynchronous cell cultures were screened for vimentin by indirect immunofluorescence microscopy, whole cell lysates derived from such cultures by immunoblotting using goat antiserum to vimentin. The minimum TPA concentration sufficient for the induction of vimentin synthesis was found to be 3 X 10(-9) M; substantially larger amounts of vimentin could be detected after treatment of cells with TPA at a concentration of 3 X 10(-8) M. At each effective TPA concentration tested, the maximum level of vimentin was reached after 18 to 24 h; it was dependent on the TPA concentration. In addition, vimentin synthesis was demonstrated employing two-dimensional polyacrylamide gel electrophoresis in combination with either fluorography or immunoblotting and autoradiography. Vimentin purified from TPA-treated MPC-11 cells as well as a protein species in whole lysates from cells labelled with [35S]methionine after TPA treatment for at least 2 h comigrated with vimentin isolated from Ehrlich ascites tumor cells. The fact that only poly(A) +RNA from TPA-treated MPC-11 cells was able to direct vimentin synthesis in vitro suggests that in MPC-11 cells vimentin production is regulated at the transcriptional level.
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PMID:Induction of vimentin synthesis in mouse myeloma cells MPC-11 by 12-0-tetradecanoylphorbol-13-acetate. 351 21

Fourteen pure oligodendrogliomas were studied by light- and electronmicroscopy and immunohistochemistry to examine glial fibrillary acidic protein (GFAP) positivity in the tumors. To compare the immunohistochemical staining patterns of neoplastic oligodendroglia and immature oligodendroglia, myelination glia in the white matter of eight normal brains from children under 6 months of age were studied. The tumors possessed light microscopic and ultrastructural features characteristic of oligodendrogliomas. Microtubules were found in the cytoplasm of nine tumors on electronmicroscopy. In one, intermediate filaments and microtubules were observed in occasional tumor cells with polygonal crystalline structures in the cytoplasm. Using the peroxidase-antiperoxidase technique, all specimens were stained for GFAP, vimentin, S-100 and neuron-specific enolase (NSE). In nine tumors, variable numbers of cells with an oligodendroglial morphology reacted positively for GFAP. All tumors were positive for S-100 and negative for vimentin and NSE. The myelination glia in the eight normal brains stained positively for GFAP but not for vimentin. Vimentin is expressed by developing, reactive and neoplastic astrocytes. Thus, GFAP positivity combined with vimentin negativity in both neoplastic and immature oligodendroglia suggests that GFAP positivity in oligodendrogliomas may reflect the transient expression of this intermediate filament by immature oligodendroglia.
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PMID:Glial fibrillary acidic protein (GFAP) in oligodendrogliomas: a reflection of transient GFAP expression by immature oligodendroglia. 353 47

Putative human rhabdomyosarcoma (RMS) has been divided into two groups according to desmin content. Twenty-five tumors with histologic features consistent with but not necessarily sufficient to prove a diagnosis of RMS were desmin-positive. More than 95% of the tumor cells were desmin-positive, suggesting a muscle origin and supporting the diagnosis of RMS. Nine tumors for which the preferred first histologic diagnosis was also RMS were desmin-negative. Reexamination of the original histologic slides together with results from intermediate filament typing resulted in a diagnosis other than RMS for all tumors in this second group, and in several instances other tests were used to prove the correctness of the final diagnosis. The results on human material were extended to a rat model system in which RMS was induced by nickel sulfide. Again, all 24 tumors tested were desmin-positive. Vimentin was coexpressed in a varying percentage of tumor cells in RMS of human and rat origin. The results show that desmin is an excellent marker for rhabdomyosarcoma, yielding few if any false-positive or false-negative results in frozen or alcohol-fixed material.
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PMID:Desmin is a specific marker for rhabdomyosarcomas of human and rat origin. 388 Oct 39

Twenty-one childhood rhabdomyosarcomas were divided into three groups on the basis of cytologic composition. The tumors in group P consisted entirely of primitive mesenchymal cells, whereas those in groups M and W were characterized by the additional presence of numerous round rhabdomyoblasts and strap cells, respectively. The tumors were studied for the universal mesenchymal intermediate filament vimentin, and for the muscle-specific intermediate filament desmin. Vimentin positivity, which tended to be more prominent in primitive tumor cells, was found in all tumors, whereas desmin was found especially in round rhabdomyoblasts and strap cells. Desmin-positive primitive cells were found only in groups M and W, not in group P. It was concluded that the differentiation from primitive mesenchymal cells to morphologically recognizable myogenic tumor cells is accompanied by an increase in desmin positivity and, presumably, a decrease in vimentin positivity. Moreover, the observations suggest the existence of a group of "committed" cells that are morphologically primitive, but desmin-positive. These cells might play an important role in the observed further differentiation of rhabdomyosarcomas under chemotherapy.
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PMID:Mesenchymal and muscle-specific intermediate filaments (vimentin and desmin) in relation to differentiation in childhood rhabdomyosarcomas. 401 80

Vimentin enriched in cytoskeletal frameworks by Triton X-100 extraction of Ehrlich ascites tumor cells and purified from a low ionic strength extract of the cell residues by (NH4)2SO4 precipitation and DEAE-Sepharose and ssDNA-cellulose chromatography in the presence of 6 M urea was highly contaminated with lipids. Thin-layer chromatography of a chloroform-methanol extract of the purified protein revealed, besides small amounts of phospholipids, the presence of large quantities of neutral lipids.
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PMID:Tenacious binding of lipids to vimentin during its isolation and purification from Ehrlich ascites tumor cells. 406 38

Poly(A)-rich RNA has been isolated from Ehrlich ascites tumor (EAT) cells and translated in a rabbit reticulocyte cell-free system. The intermediate filament protein, vimentin, was found to be a major translation product. Fractionation of the poly(A)-rich RNA by sucrose gradient centrifugation showed that the vimentin mRNA had a sedimentation coefficient of about 18 S corresponding to a molecular size of about 2000 nucleotides. This means that it must possess significant non-coding regions. Vimentin synthesized in vitro was identical to native vimentin with regard to its precipitability with ammonium sulphate, extent of phosphorylation and susceptibility to digestion by the vimentin-specific, Ca2+-activated proteinase. Poly(A)-rich RNA was also isolated from a number of tissue-culture cells and rat liver, which contain varying amounts of vimentin in situ. It was found that the amount of vimentin synthesized by these RNA preparations in a rabbit reticulocyte cell-free system is proportional to the amount of vimentin detectable in situ, suggesting that the amount of cellular vimentin may be controlled at the level of transcription.
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PMID:Synthesis of vimentin in a reticulocyte cell-free system programmed by poly(A)-rich RNA from several cell lines and rat liver. 618 90

Frozen sections of human renal carcinomas were studied in indirect immunofluorescence using antibodies against intermediate filaments of cytokeratin, desmin and vimentin type, and against proximal tubular brush border and distal tubular Tamm-Horsfall glycoprotein antigens, as well as with fluorochrome-labeled lectins in an attempt to study the origin and stage of differentiation of renal carcinomas. Eighty per cent of the renal carcinomas expressed the brush border antigens, whereas the Tamm-Horsfall glycoprotein could not be found. Antibodies against epidermal cytokeratins reacted only with collecting ducts in normal kidney, whereas antibodies against cytokeratins of Madin-Darby canine kidney epithelial cell line also reacted with glomerular and tubular epithelium. In 93% of the carcinomas tumor cells showed reactivity with both types of antikeratin antibodies. Vimentin, the cytoskeletal protein of mesenchymal cells, was present in the carcinoma cells of 53% of the tumors, although it was not present in normal tubular epithelium. Moreover, vimentin was expressed together with cytokeratin in the carcinoma cells in 57% of the keratin-positive samples as judged by double immunostaining, whereas the muscle type of intermediate filament protein, desmin, was not seen in the malignant cells. Binding sites for Lotus tetragonolobus agglutinin and soybean agglutinin, normally present in the cells of proximal tubules, were lacking or only faintly detectable in the neoplastic cells. Dolichos biflorus agglutinin, normally present in collecting ducts, was not detected in the tumors. The results show that most renal carcinomas express cytokeratin antigens as a sign of their epithelial origin and also show characteristics of proximal tubular cells. On the other hand, the results indicate that lectin-binding sites typical for normal differentiated tubular cells are profoundly modified in renal carcinomas. Ulex europaeus agglutinin did not bind to the malignant cells but decorated the endothelial cells of the tumors.
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PMID:Cellular origin and differentiation of renal carcinomas. A fluorescence microscopic study with kidney-specific antibodies, antiintermediate filament antibodies, and lectins. 619 32


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