Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

DNA aneuploidy has been demonstrated to be an independent parameter of prognostic significance in malignant melanomas. In order to improve the detection of DNA aneuploidy in malignant melanomas, and to minimize diploid non-tumor cells in the sample, we developed a two-color staining strategy for S100 protein and DNA content in paraffin embedded samples. The ability to detect aneuploidy, defined as DNA ploidy index less than or equal to 0.90 or greater than or equal to 1.10, in 37 stage I malignant melanoma samples by flow cytometry analysis was significantly improved from 10.8% of cases using traditional one-color analysis for DNA content only (propidium iodide) to 32.4% of cases using two-color analysis for simultaneous measurement of both DNA (propidium iodide) and S100 protein (fluorescein conjugated antibody) (Chi-square with Yates' correction; p less than 0.05). The largest increase in sensitivity was found in level I and II melanomas less than or equal to 0.76 mm in thickness. In addition, we report the new observation that multiple S100 protein-positive subpopulations were found significantly more frequently in malignant melanomas (23/37 cases) than in compound melanocytic nevi (5/22 cases) (Chi-square with Yates' correction; p less than 0.01). These findings suggest that there is a previously unsuspected degree of tumor heterogeneity even in thin, presumably early, malignant melanomas.
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PMID:Improved detection of aneuploidy in malignant melanoma using multiparameter flow cytometry for S100 protein and DNA content. 276 39

A case of malignant melanoma primary of the facial skin presenting with pre-auricular and submandibular masses, both thought to be metastatic melanoma, is reported. The case illustrates the practical application of a recently developed and commercially available specific anti-melanoma monoclonal antibody, HMB 45, which is useful in distinguishing between metastatic melanoma to a submaxillary lymph node and a synchronous primary parotid, poorly differentiated adenocarcinoma. The value of specific anti-melanoma antibody in conjunction with an antibody panel that includes S100, keratin, and epithelial membrane antigen in the distinction of melanomas from anaplastic carcinomas is discussed.
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PMID:Distinction between metastatic melanoma and primary parotid gland carcinoma using monoclonal HMB 45 antimelanoma antibody: report of a case. 291 77

A postembedding Protein A-colloidal gold technique was used for the ultrastructural immunocytochemical investigation of S100, tubulin, and cytoskeletal proteins in a Lowicryl K4M-embedded melanoma with numerous microtubules. S100 protein was localized in the cytoplasm and the nuclei of tumor cells. Melanosomes were not labeled with S100. Perinuclear intermediate filaments and filaments in cytoplasmic processes reacted positively for vimentin. The straight, rod-shaped, parallel intracisternal microtubules failed to react with antisera to tubulin, S100, vimentin, cytokeratin, neurofilaments, desmin, glial fibrillary acidic protein, and immunoglobulin light chains. These results give an improved correlation between the ultrastructural and immunocytochemical characteristics of the tumor, confirm the melanocytic origin of it, and demonstrate the application and usefulness of the postembedding immunogold method in the investigation of the protein composition of subcellular structures.
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PMID:Postembedding immunogold electron microscopy for S100, tubulin, and cytoskeletal proteins in an amelanotic malignant melanoma. 292 90

The majority of melanocytic tumours are easily diagnosed but they become a problem when they are amelanotic and the tumour cells resemble those of other tumours. This applies particularly to secondary melanoma. Detection of S100 protein is a useful identifying marker. S100 protein, so named for its solubility in saturated ammonium sulphate, is derived from brain tissue. It is a dimer and belongs to a calcium binding group of proteins. The protein was first thought to be in neural or neural crest derived tissues but has been found in chondrocytes, adipocytes, myoepithelial cells, dendritic cells of lymphoid tissue, Langerhans cells and T lymphocytes. The protein is present in a high proportion of malignant melanomas and nevocytic nevi of skin, but is less positive in eye melanomas. It is present in gliomas, Schwannomas and neurofibromas but not in neurone derived tumours such as neuroblastomas. Chondromas, chondrosarcomas, liposarcomas, some osteogenic sarcomas and some histiocytic tumours are positive. The tumours that do not contain S100 protein are listed. Pending development of melanoma-directed monoclonal antibodies, the use of anti-serum to S100 protein plus anti-keratin and anti-leukocyte reagents is useful in the identification of tumours of doubtful histogenesis.
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PMID:S-100 protein as a marker for melanocytic and other tumours. 299 6

We used immunohistochemistry to evaluate four cytologically malignant cutaneous neoplasms on the face or neck of elderly individuals. All four lesions were composed of a dermal proliferation of spindle and pleomorphic giant cells. Differential diagnosis included spindle cell carcinoma, atypical fibroxanthoma, malignant melanoma, leiomyosarcoma, and angiosarcoma. All four neoplasms were strongly immunoreactive for vimentin and negative for cytokeratin, S100 protein, desmin, and factor-VIII-related antigen. Focal immunoreactivity for lysozyme and/or a1-antichymotrypsin was seen in the giant cells of each lesion. These results supported the diagnosis of atypical fibroxanthoma in each instance. Immunohistochemical staining can provide useful information for distinguishing among malignant cutaneous spindle cell tumors.
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PMID:Immunohistochemistry: a useful adjunct in the evaluation of malignant cutaneous spindle cell tumors. 320 Dec 97

Ninety-one skin biopsy specimens previously identified as lentigo maligna were examined for the presence of microinvasion, using the demonstration of S100 protein within atypical cells as the means for locating these superficial foci. In 14 cases, atypical melanocytes were identified, most often in the papillary dermis. The mean depth of invasion in this group was 0.23 mm with a range of 0.10 mm to 0.75 mm. In these cases, atypical cells were difficult if not impossible to identify in routinely processed sections, either because the invasive cell was a spindle cell variant and indistinguishable from a fibrohistiocytic cell, because the invasive cells were occasionally solitary or in small groups, or because there was an inflammatory infiltrate that obscured the tumor cells. Recent studies of lentigo maligna melanoma have revealed no better prognosis when compared to that of other forms of malignant melanoma after normalization for depth and body location. We therefore advocate close examination of lentigo maligna with the use of appropriate immunohistochemical techniques if there are areas of dermal fibrosis or inflammation that might obscure invasion.
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PMID:Microinvasive lentigo maligna melanoma. 331 17

The efficacy of two new monoclonal antibodies with cell lineage-restricted reactivity (HMB-45 [melanocytes] and anti-synaptophysin [neuroepithelial cells]) was compared with that of "traditional" antibody panels in the delineation of malignant melanoma (MM) of the sinonasal region, nasopharyngeal carcinoma (NPC), and olfactory neuroblastoma (ONBL). HMB-45 recognized all of eight melanomas and stained one of five neuroblastomas, but failed to label any of 12 cases of NPC. All examples of ONBL were stained by anti-synaptophysin; other tumors were nonreactive with this reagent. A panel of antibodies to cytokeratin, vimentin, epithelial membrane antigen, and S100 protein was also effective in discriminating between MM, NPC and ONBL. These results suggest that HMB-45 and anti-synaptophysin are comparable in utility to more extended antibody panels in the diagnosis of sinonasal malignancies, but only if used in combination with one another.
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PMID:Immunohistochemical diagnosis of sinonasal melanoma, carcinoma, and neuroblastoma with monoclonal antibodies HMB-45 and anti-synaptophysin. 337 60

Clinical and pathologic details in 14 cases of desmoplastic malignant melanoma were reviewed. The study group included ten men and four women with a median age of 58 years. Anatomic locations such as the head and neck area (four cases), limbs (five cases), and trunk (five cases) were involved with equal frequency. Follow-up information (median period, 4.6 years) was available for 12 patients, of whom four are alive and disease free, six have had local tumor recurrence, and two have died of their disease. Histologically, these lesions consisted of a malignant fibroblastic skin tumor intimately associated with a superficial melanoma (ten cases) or melanocytic dysplasia (four cases) that often extended deeply to the subcutaneous fat. Helpful diagnostic features included the presence of neurotropism, a lymphocytic infiltrate, and unusual patterns of triangular and periadnexal lamellar fibroplasia. Of the immunohistochemical markers employed, antisera to S100 protein and vimentin yielded the most consistent positive results. Immunostaining with NK1/C-3 (antimelanoma monoclonal antibody) was not helpful. Ultrastructural evidence of fibroblastic and schwannian differentiation was seen. We conclude that the altered morphologic melanomas is associated with a relatively favorable prognosis and believe that careful attention to light microscopic detail with immunohistochemical and electron microscopic assistance will elucidate the diagnosis in most cases.
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PMID:Desmoplastic malignant melanoma. A clinicopathologic study of 14 cases. 341 43

To identify melanoma associated antigens (MAAs) shared by human and guinea pig melanoma cells, a battery of murine monoclonal antibodies (MoAbs) to human MAA and an antiserum to S100 protein were tested with four newly established guinea pig melanoma cell lines. Only the monoclonal antibodies 149.53 and 225.28 which recognize distinct determinants of the human high molecular weight-MAA (HMW-MAA) reacted with all four guinea pig melanoma cell lines. To compare the binding site of MoAbs 149.53 and 225.28 with guinea pig and human melanoma cells, inhibition binding experiments were performed with antiidiotypic monoclonal antibodies which completely inhibit the binding of MoAbs 149.53 and 225.28 to human melanoma cells. The binding of MoAb 149.53 to guinea pig melanoma cells was partially inhibited by antiidiotypic MoAbs MF9-10 and MK1-180 which recognize distinct private idiotopes within the antigen combining site of MoAb 149.53. On the other hand the binding of MoAb 225.28 to guinea pig melanoma cells was completely inhibited by antiidiotypic MoAbs MF11-30 and TK1-F2 which recognize distinct private idiotopes within the antigen combining site of MoAb 225.28. These results suggest that the determinant recognized by MoAb 149.53 on guinea pig melanoma cells is similar but not identical to that recognized on human melanoma cells, while the determinants recognized by MoAb 225.28 on the two types of cells do not display any detectable differences under the experimental conditions tested. The target structure on the guinea pig melanoma cells identified by MoAbs 149.53 and 225.28 is a Mr 280,000 molecule which has the same apparent molecular weight as one of the two subunits of the HMW-MAA synthesized by human melanoma cells. Sequential immunoprecipitation experiments with guinea pig melanoma cells showed that the determinant recognized by MoAb 149.53 is expressed on a subpopulation of the molecules recognized by MoAb 225.28. Immunohistochemical staining with MoAb 225.28 of a variety of different tissues from normal adult guinea pigs showed that the corresponding antigenic determinant is detectable only in basal cells of epidermis and hair follicles of skin. S100 protein, which is a cytoplasmic constituent of normal human melanocytes, benign nevi, and malignant melanocytes, was also detected in the cytoplasm of the four cultured guinea pig melanoma cells lines. The results of the present investigation may lead to a better understanding of the phylogenetic evolution of the human HMW-MAA and suggest that guinea pig melanoma may serve as a useful animal model for immunobiological studies and carcinogen-induced tumorigenesis investigations.
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PMID:Cross-reactivity of murine anti-human high molecular weight-melanoma associated antigen monoclonal antibodies with guinea pig melanoma cells. 347 98

In ten cases of neurotropic melanoma, patients presented with nodules composed of amelanotic, deeply infiltrating neuroid fascicles. Only four cases were clinically suggestive of melanoma. In eight of the tumors, a precursor lesion was found histologically and provided a major clue to the diagnosis. In seven cases, the dysplastic precursor was lentiginous, while a superficial spreading pattern was present in one. Initial surgery was often inadequate because of the difficulty in defining tumor margins and the lack of pigment. In seven of the tumors, S100 protein was demonstrated within the invasive spindle cell component by the immunoperoxidase method. This finding was negative in three cases, two of which showed positive staining of the precursor and nerve filaments, indicating that the absence of S100 protein cannot be used as an exclusion criterion for neurotropic melanoma.
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PMID:Neurotropic Melanoma. A variant of desmoplastic melanoma. 360 70


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