Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cytoskeleton is considered to be important for maintaining cell shape and facilitating cell movement. In the present study, the expression of cytoskeletal components is examined in benign and malignant melanocytic skin tumors. Paraffin sections of 75 cases (25 each of nevocellular nevus, primary malignant melanoma, and cutaneous metastases of malignant melanoma) were stained with antibodies to tubulin, myosin, actin, and vimentin using a three-step immunoperoxidase method. The staining results were assessed independently for tumor cells and stroma cells in comparison to inbuilt reference structures. Vimentin is found in all melanocytic lesions in the tumor as well as in the stroma cells. In malignant lesions, the tumor cell staining intensity varies between neighboring regions; particularly in malignant melanoma the staining is pronounced in the tumor periphery (chi 2 test: p less than 0.05). Actin is only weakly positive in nevus cells and primary melanoma tumor cells, but strongly expressed in metastatic tumor cells (p less than 0.001). Nevus fibroblasts are only weakly positive, whereas the stroma fibroblasts in the malignant lesions are strongly positive (p less than 0.001). The same is true for myosin and tubulin expression in dermal fibroblasts (p less than 0.001), whereas the tumor cells are equally (weakly) positive in all melanocytic lesions. Our study shows that there are significant differences in the immunohistochemical expression of cytoskeletal components in various melanocytic tumors. There is an elevated expression of vimentin and actin in the tumor cells, particularly of metastatic lesions. However, the most pronounced differences are found in the dermal fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of cytoskeletal components in melanocytic skin lesions. An immunohistochemical study. 202 88

A case of intracranial fibrous xanthoma (xanthofibroma) is reported. Intracranial fibrous xanthoma in infancy under the age of 1 year is extremely rare. This patient was a 8-month-old boy with a history of convulsive seizure. He had a previously known chest wall tumor which was diagnosed as fibrous xanthoma of the skin. Plain CT scan revealed a well defined high density area in the left temporal lobe. The area was well enhanced with contrast media. At operation, it was found that the tumor did not attach to dura mater and was almost well demarcated. Total removal of the tumor was performed. The patient has been doing well for these 6 months following craniotomy, with no sings of recurrence and no neurological deficits. Histologically, the tumor was composed of fibroblastic cells and foamy phagocytic cells in storiform pattern. Some multinucleated giant cells were found. Immunohistochemistry technique revealed that the tumor cells were negative for GFAP, positive for Vimentin, positive for S-100 protein and negative for EMA. Our studies support the diagnosis of intracranial fibrous xanthoma coexistent with the same tumor found in the subcutaneous space of the chest wall of a boy under 1 year of age. We regard it as a rare incidence. Differential diagnosis and the characteristics of fibrous xanthoma were discussed.
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PMID:[Intracranial fibrous xanthoma (xanthofibroma) in an infant: a case report]. 203 18

The occurrence of vimentin-positive and GFAP-negative cells in gliomas induced by transplacental ENU in the rat is not yet clarified. Because of the temporal overlapping between neural cytogenesis and tumoral transformation in this experimental model, the expression of vimentin and GFAP in the developing rat brain can give some information. Vimentin is constantly present in the processes of radial glia; the earliest GFAP-positive cells are mature astrocytes appearing when vimentin-positive radial glia is still abundantly present. Transitional immunoreactivity from radial glia to stellate astrocytes, also with double staining in immune electronmicroscopy, is not demonstrable; the role of radial glia as a precursor cell to mature astrocytes is not confirmed. It can be hypothesized that radial glia is a target of ENU, and that its pattern of intermediate filaments is maintained in the tumor phenotype.
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PMID:Neurocytogenesis and tumor development in the rat. 209 93

Vimentin expression, growth fractions (GF), and estrogen receptor (ER) levels were determined for 90 untreated primary breast carcinomas. Coexpression of keratin and vimentin was found in approximately 20% of the tumors regardless of menopausal status. Vimentin was expressed preferentially in tumor cells of high-grade ductal breast carcinomas (15 of 28 histologic grade 3 vs. 0 of 40 grades 1 and 2). Vimentin expression was found preferentially in tumors with high GF (greater than 15% Ki-67 positive by immunoperoxidase staining) and low ER levels (less than 60 fmols/mg protein by a monoclonal enzyme immunoassay). Sixty-eight percent of tumors in this group were vimentin positive and 88% of all vimentin-positive tumors fell into this category. More than 50% of the tumor cells coexpressed vimentin and keratin. Thus, vimentin expression may be helpful in identifying a substantial subset of ER-independent breast carcinomas with poor prognostic indicators.
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PMID:Vimentin is preferentially expressed in human breast carcinomas with low estrogen receptor and high Ki-67 growth fraction. 215 47

Seven cases of mixed glioblastoma multiforme (GBM) and sarcoma, or gliosarcoma (GS) and six cases of GBM with a prominent pilocytic or spindle cell component were studied with a panel of ten antibodies using the ABC method. All 13 cases were originally diagnosed as GS based on hematoxylin and eosin- (H&E) and reticulin-stained sections. In all GS, the glial component stained strongly for glial fibrillary acidic protein (GFAP), and most stained for S-100 protein, while the sarcomatous areas of GS did not stain for either of these antigens. This resulted in a characteristic, bimorphic marmorate staining pattern. In contrast, spindled GBM stained diffusely for GFAP and S-100 protein. Vimentin was detected in neoplastic glia of both GBM and GS and in the sarcomatous foci of GS. A spectrum of cytokeratins, Factor VIII, desmin and neurofilament were not detected in either GS or GBM. Actin, Leu 7 and alpha-1-antichymotrypsin were focally and inconsistently found in both GS and GBM. Perithelial spindle cell proliferations and intramural spindle cells within thick-walled vessels stained for GFAP, S-100 protein and/or vimentin. These studies confirm that GS is a true biphasic neoplasm that frequently cannot be distinguished from pilocytic or spindled GBM on routine histologic examination. Invasion of the dura, leptomeninges, and hyperplastic or hypertrophied blood vessels by malignant glial cells particularly confounds interpretation of H&E and reticulin stains. Immunohistochemical staining for GFAP complements the reticulin stain in confirming the presence of two cell populations in GS.
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PMID:Gliosarcoma: a histologic and immunohistochemical reaffirmation. 215 18

Two hundred sixty-two invasive breast carcinomas dating from 1979 to 1984 were tested for vimentin and keratin on formaldehyde-fixed paraffin-embedded sections. None of 26 lobular carcinomas expressed vimentin. Vimentin expression in 10% or more of tumor cells was found in 78% of medullary (14 of 18), in 16% of ductal not otherwise specified (NOS) (35 of 214), and in two of four mucinous carcinomas. A further seven tumors showed vimentin expression in less than 1% to 10% of the cells. Vimentin was expressed in tumor cells of 30% (28 of 93) of grade III invasive ductal NOS carcinomas versus 7% (7 of 105) of grade II and 0% of grade I carcinomas (0 of 10). Vimentin was found to be preferentially expressed in tumors growing in broad, often anastomosing bands or sheets with extensive necrosis, scanty supportive stroma, high nuclear grade, and numerous mitoses. The authors conclude that vimentin is not detected in lobular carcinomas, but is preferentially expressed in medullary and in high-grade ductal NOS breast carcinomas.
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PMID:Vimentin is preferentially expressed in high-grade ductal and medullary, but not in lobular breast carcinomas. 217 10

The subject was an 85-year-old woman, who had been diagnosed as having an ovarian cancer and carcinomatous peritonitis and had been treated conservatively. She subsequently died from respiratory and renal insufficiency, and the autopsy that followed revealed that her pelvic cavity had been filled by a tumorous mass that size of a child's head. Histologically, the tumor was a serous cystadenocarcinoma of the ovary. Moreover another tumor, also the approximate size of a child's head, was found sited extramurally, beneath the posterior wall mucosa of the stomach body. Histological inspection of this tumor revealed a proliferation of round oval, and spindle-shaped tumor cells. A vacuolation of the cytoplasms and karyomitosis to the extent of 10/50 HPF also were observed. Based on the findings of being positive for Vimentin and a negative EMA, this tumor was diagnosed as being a malignant leiomyoblastoma of the stomach smooth muscle. The leioblastoma is a relatively uncommon neoplasm, and recent advances in immunohistochemical staining have indicated that some of these tumors are not only of smooth muscle derivation but also of nerve origin. Therefore, this tumor, given its morphological characteristics, had been generalized in this case as a gastric stromal tumor, and with negative findings for Desmin and S-100 protein, as well as positive for Vimentin.
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PMID:[An autopsy case of extramural malignant leiomyoblastoma of the stomach with ovarian cancer: an immunohistochemical study]. 219

Immunoreactivity with monoclonal antibodies against the intermediate filament protein, vimentin, and epithelial membrane antigen (EMA) was examined in 330 cases of lymphoma (317 non-Hodgkin's and 13 Hodgkin's lymphomas), 12 reactive lymph nodes and mononuclear cells of the peripheral blood using either indirect immunoperoxidase staining or the avidin-biotin immunoperoxidase complex technique. The cell origin of each tumor was established using a panel of monoclonal antibodies against lymphocyte differentiation antigens. There were 41 T-cell, 247 B-cell and 29 undetermined lymphomas, and 13 cases of Hodgkin's disease in the series. Vimentin was expressed in 24 T-cell lymphomas (58.5%) and 60 B-cell lymphomas (24.2%). This difference in frequency was statistically significant. Vimentin expression in follicular lymphomas was less frequent than in diffuse B-cell lymphomas. In diffuse lymphomas, small and medium cell types were more reactive with anti-vimentin than large cell types. Reed-Sternberg cells (R-S cells) in Hodgkin's disease were positive for vimentin in 11 cases (84.6%). The frequency of EMA reactivity in lymphomas was low, particularly in T-cell lymphomas. No positive cases were found among follicular lymphomas. In diffuse non-Hodgkin's lymphomas, EMA was expressed only in mixed and large cell types, but never in smaller ones. In conclusion, monoclonal antibodies against vimentin and EMA appear to be of limited usefulness for the diagnosis of non-Hodgkin's lymphomas, but anti-vimentin antibody may be used as an adjunct to the diagnosis of R-S cells in Hodgkin's disease.
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PMID:Expression of vimentin and epithelial membrane antigen in human malignant lymphomas. 223 13

Immunostaining patterns of glial fibrillary acidic protein (GFAP), S-100 protein (S-100p) and vimentin were studied using immunohistochemical techniques on 48 paraffin embedded glial tumors. GFAP was positive in all tumor cases except in two oligodendrogliomas. S-100p was found in most astroglial tumors and in half of the oligodendrogliomas. Vimentin was positive in many astrocytomas but in no oligodendrogliomas. Most astroglial tumors showed similar immunoreactivity for GFAP and S-100p. Fibrillary processes, however, showed stronger and more crisp staining with anti-GFAP than with anti-S-100p, whereas cell nuclei were labeled only for S-100p. Vimentin was localised mainly in juxtanuclear positions. In many astrocytomas with different degrees of malignancy co-expression of GFAP, S-100p and vimentin was found. The presence of GFAP and S-100p was not correlated with the degree of differentiation in astrocytomas. Vimentin was more positive in anaplastic astrocytomas but this finding was not statistically significant. It seems that GFAP is a superior marker to S-100p and vimentin in the identification of human gliomas.
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PMID:An immunocytochemical comparison of glial fibrillary acidic protein, S-100p and vimentin in human glial tumors. 231 88

The ability of purified nuclear lamin A, lamin B, lamin C, and vimentin from Ehrlich ascites tumor cells to bind nucleic acids was investigated in vitro via a quantitative filter binding assay. At low ionic strength, vimentin bound more nucleic acid than the nuclear lamins and showed a preference for G-containing nucleic acids. Nuclear lamins A and C were quite similar in their binding properties and bound G- and C-containing nucleic acids preferentially. The binding of poly(dT) by the lamins A and C was reduced in competition experiments by both poly(dG) and poly(dC), but not by poly(dA). Lamin B bound only oligo and poly(dG); no other nucleic acids tested were bound or could compete with the binding of oligo(dG). Vimentin, lamin A, and lamin C specifically bound a synthetic oligonucleotide human (vertebrate) telomere model. The Ka for vimentin (2.7 X 10(7) M-1) was approximately 10-fold higher than those for lamin A (2.8 X 10(6) M-1) and lamin C (2.9 X 10(6) M-1). Lamin B did not bind detectable amounts of the telomere model. Washing of lamin A- and lamin C-nucleic acid complexes, formed at low ionic strength, with solutions containing 150 mM KCl resulted in the elution of 30% of bound poly(dG)12-18 and 70% of bound synthetic oligonucleotide telomere model. These results, using purified individual proteins, are in good agreement with data from competition experiments with vimentin but are at odds with data obtained previously using a crude preparation of nuclear matrix proteins containing all three nuclear lamin proteins (Comings, D. E., and Wallack, A. S. (1978) J. Cell Sci. 34, 233-246). The nuclear lamins A and C and vimentin possess nucleic acid-binding properties that might permit their binding to specific base sequences and/or unique DNA structure, such as that observed for the binding of the telomere model. The significance of the higher affinity binding of nucleic acids by the cytoplasmic protein vimentin (compared with the nuclear lamins) remains to be elucidated.
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PMID:The in vitro DNA-binding properties of purified nuclear lamin proteins and vimentin. 234 65


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