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)

We have established a number of cell lines from Merkel cell carcinoma (MCC) of the skin. In many respects these cell lines resemble those established from small cell lung cancer (SCLC) and it is difficult to differentiate between metastatic MCC and SCLC on morphological or histochemical criteria. Both are thought to be neuroendocrine tumours and may express a number of neuroendocrine markers. SCLC cell lines express the octamer-DNA binding transcription factor brn-2 gene products N-Oct3 and N-Oct5, which are restricted to the neuroectodermal cell lineage. In DNA binding studies using a consensus octamer recognition site we have found that 4 of 8 MCC cell lines examined expressed brn-2 in at least trace amounts compared with 3 SCLC cell lines which all expressed brn-2 proteins at high levels. Moreover, these DNA binding studies were extended by using a high-affinity brn-2 recognition site related to the degenerate octamer TAATGARAT-motif. This identified a novel DNA binding protein in a subset of MCC cell lines. The protein was absent from the three SCLC cell lines, melanoma cells and brain tissue. This binding activity, which we term Merkel cell DNA nuclear (MNF), was shown to be specific by competitive inhibition with oligonucleotide binding sites and was not inhibited by polyclonal antisera against the Oct-1, Oct-2 or Brn-2 proteins. This protein may serve as a unique marker for MCC compared with SCLC cells and may be involved in regulating the Merkel cell phenotype.
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PMID:A nonconsensus octamer-recognition sequence (TAATGARAT-motif) identifies a novel DNA binding protein in human Merkel cell carcinoma cell lines. 802 90

Radiation therapy is an acceptable alternative for the treatment of many malignancies of the skin. Results are gratifying, and long-term sequelae are few. In basal cell and squamous cell carcinomas, radiation is often the best treatment when surgery is expected to cause excessive morbidity or mortality or require extensive reconstruction. Radiation should be considered as first-line treatment for tumors in the midfacial triangle. It is also very acceptable treatment for Kaposi's sarcoma and mycosis fungoides. Radiation can be used for melanoma, although it is not standard first-line therapy. Radiation is probably the treatment of choice for Merkel cell carcinoma.
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PMID:Radiation therapy for skin tumors. 846 44

The bcl-2 proto-oncogene, which is involved in the regulation of apoptosis, is expressed in a wide variety of fetal and adult tissues. We and others have demonstrated recently that in the human skin melanocytes, nervus cells and melanoma cells express bcl-2 constitutively. In the present study, we have analysed the expression of bcl-2 in Merkel cells and in Merkel cell carcinomas. In 2 colour immunofluorescence staining, normal human Merkel cells as identified by the expression of cytokeratins 8, 18 and 20, were also anti-bcl-2 positive. Staining of paraffin sections of Merkel cell carcinomas with an anti-bcl-2 monoclonal antibody revealed strong bcl-2 protein immunoreactivity in all 5 tumors tested. Serial sections of Merkel cell carcinomas stained with the monoclonal antibodies CK 20, CAM 5.2, anti-neuron-specific enolase and anti-bcl-2 showed that the anti-bcl-2 reactive cells were indeed tumor cells. Our data demonstrate for the first time, that normal human Merkel cells and Merkel cell carcinomas express bcl-2 constitutively. Considering the biological function of the bcl-2 proto-oncogene, i.e., its anti-apoptotic effect, it is conceivable that in the near future, modulations of the expression of this protein may offer a new strategy in the therapy of bcl-2 expressing tumors such as Merkel cell carcinoma.
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PMID:Merkel cells and Merkel cell carcinoma express the BCL-2 proto-oncogene. 884 Jan 59

Fifty-nine cases of tumors, 51 taken from the thyroid gland including 17 well-differentiated papillary, 1 medullary and 3 follicular carcinomas, 14 follicular adenomas, 16 nodular goiters and 8 cases selected from other sites; 5 breast carcinomas; 1 melanoma; 1 Merkel cell tumor; and 1 squamous cell carcinoma of the uterine cervix, were investigated for intercellular adhesion molecule-1 (ICAM-1) expression. All cases of well-differentiated papillary thyroid carcinoma showed positivity for ICAM-1, whereas the follicular carcinomas, follicular adenomas, and all but one nodular goiters were negative. It is suggested that the occurrence of ICAM-1 on the thyroid cell surfaces in well-differentiated papillary thyroid carcinomas may contribute to the understanding of their biology and could be of potential significance for diagnostic purposes.
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PMID:Intercellular adhesion molecule-1 (ICAM-1) immunoreactivity in well-differentiated thyroid papillary carcinomas. 882 57

The bel-2 proto-oncogene, which is involved in the regulation of apoptosis, is expressed in a wide variety of fetal and adult tissues. We and others have demonstrated recently that in the human skin melanocytes, nevus cells and melanoma cells express bcl-2 constitutively. In the present study, we have analysed the expression of bcl-2 in Merkel cells and in Merkel cell carcinomas. In 2 colour immunofluorescence staining, normal human Merkel cells as identified by the expression of cytokeratins 8, 18 and 20, were also anti-bcl-2 positive. Staining of paraffin sections of Merkel cell carcinomas with an anti-bcl-2 monoclonal antibody revealed strong bcl-2 protein immunoreactivity in all 5 tumors tested. Serial sections of Merkel cell carcinomas stained with the monoclonal antibodies CK 20, CAM 5.2, anti-neuron-specific enolase and anti-bcl-2 showed that the anti-bcl-2 reactive cells were indeed tumor cells. Our data demonstrate for the first time, that normal human Merkel cells and Merkel cel carcinomas express bcl-2 constitutively. Considering the biological function of the bcl-2 proto-oncogene, i.e., its anti-apoptotic effect, it is conceivable that in the near future, modulations of the expression of this protein may offer a new strategy in the therapy of bcl-2 expressing tumors such as Merkel cell carcinoma.
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PMID:Merkel cells and Merkel cell carcinoma express the BCL-2 proto-oncogene. 873 19

An 82-year-old Caucasian man developed an ulcerated mass on the anterior mandibular gingiva. Five years previously he had been treated for a Merkel cell carcinoma (MCC) on his right cheek. Histopathologic examination showed small tumor cells with scanty cytoplasm, suggestive of malignancy. Immunohistochemical studies were performed with the use of nine antibodies. S-100 protein and leukocyte common antigen were helpful in ruling out melanoma and lymphoma. Pronounced reaction was shown for cytokeratin 20, a new histodiagnostic marker whose expression is almost entirely confined to Merkel cells, the gastric epithelium, and urothelium. The tentative diagnosis of metastasis of MCC was confirmed. Immunohistochemical studies are useful diagnostic aids in the establishment of the diagnosis of Merkel cell carcinoma.
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PMID:Gingival metastasis of merkel cell carcinoma: a case report. 885 Mar 57

Histological interpretation of frozen sections made during Mohs' micrographic surgery may be difficult, depending on the morphological and staining characteristics of the tumour and on the nature of the associated inflammatory infiltrate. We have employed an adaptation of micrographic surgery in which horizontal, formalin-fixed, paraffin-embedded sections were used to improve histological assessment in the excision of 18 non-melanoma skin tumours in which frozen sections had been or were likely to be unsatisfactory. We describe our experience of this method in the management of squamous cell carcinomas (11), extramammary Paget's disease (two), microcystic adnexal cell carcinomas (two), dermatofibrosarcoma protuberans (two), and primary cutaneous neuroendocrine carcinoma (Merkel cell carcinoma) (one). The use of horizontal paraffin-embedded sections lengthens the duration of the procedure but facilitates accurate assessment of histological sections in selected tumours.
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PMID:Excision of selected skin tumours using Mohs' micrographic surgery with horizontal paraffin-embedded sections. 897 11

In the Japanese, melanoma most commonly involves the plantar surface. Among 61 patients with plantar melanoma, we diagnosed 50 patients as acral lentiginous melanoma (ALM), nine as nodular melanoma, and two as superficial spreading melanoma. Partial or complete loss of pigment was observed in four of the nine nodular melanoma cases and in the nodular portions of eight ALM cases. All 12 such nodular lesions were ulcerated. The clinical diagnosis of malignant melanoma was easily made in the eight patients with ALM by the characteristic pigmentary changes around the nodule. The presence of some remaining pigment was found to be helpful in making the diagnosis in two lesions of nodular melanoma which, at first, had been clinically diagnosed as eccrine poromas. One of two completely amelanotic nodular melanomas was strongly suspected to be a melanoma because there was a history of a pre-existing pigmented macule before the development of the nodule. The other one required histopathological differentiation from Merkel cell carcinoma. Based on these findings and compared with melanoma on other parts of the body, pigmentation noted in the ulcerative nodule of plantar melanoma seems to disappear easily. This causes difficulty in distinguishing it from other skin tumours.
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PMID:Non-pigmented nodular plantar melanoma in 12 Japanese patients. 1046 30

The technology of sentinel node lymphoscintigraphy has made it possible to map and identify the lymph nodes draining the site of a primary cutaneous malignancy. This technique is now being used in the treatment of melanoma, and breast and vulvar carcinoma. With melanoma and breast carcinoma, the histology of the sentinel lymph node (SLN) has been found to be reflective of the histology of the remainder of the nodal basin. The concept of sampling the SLN is to provide an accurate staging for the entire nodal basin, obviating the need for a complete lymphadenectomy if the SLN is negative. It is believed that cutaneous malignancies with a propensity for regional metastasis, such as neuroendocrine carcinoma of the skin, may spread via a similar lymphatic pathway involving an SLN. Using this technique we identified and excised the SLNs in a patient with a neuroendocrine carcinoma of the skin that contained the only focus of metastatic disease. Although this technique is still investigational we believe it holds great promise in being able to detect occult metastatic nodal disease in clinically node-negative patients.
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PMID:Sentinel node excision for the diagnosis of metastatic neuroendocrine carcinoma of the skin: a case report. 932 12

Merkel cell carcinoma (MCC) is a malignant tumor of the skin with a well-established neuroendocrine phenotype but an unknown histogenetic origin. Cytogenetic and molecular studies have shown evidence for genetic changes on the distal portion of chromosome 1p in different tumors with well-established neuroendocrine origins, specifically neuroblastomas, malignant melanomas, and pheochromocytomas. Involvement of chromosome 1 in MCC recently has been demonstrated by cytogenetic analysis and analysis of loss of heterozygosity (LOH) in metastatic tumor tissue. We performed analysis of LOH of the distal portion of chromosome 1p in paraffin material of 10 primary MCCs after tissue microdissection, using the polymorphic markers D1S160, D1S243, D1S468, D1S1646, and D1S1598. Seven of 10 analyzed MCCs shared a distal deletion involving 1p35-36. None of the cases showed 1p involvement proximal to 1p35. The findings are similar to those described for malignant melanoma, pheochromocytoma, and neuroblastoma, tumors known to originate from neural crest cells. In conjunction with previous cytogenetic data, we conclude that Merkel cell carcinogenesis shares pathogenetic mechanisms with other neoplasms of neural crest derivation.
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PMID:Genetic changes associated with primary Merkel cell carcinoma. 957 74


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