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)

In split epidermal sheets with clinically normal appearance a quantitative study was carried out on dopa-positive cells in the vicinity of malignant melanomas. These data were then compared with the number of melanocytes found in the skin of the contralateral body side of the same patient. In the epidermis around superficial spreading melanoma and lentigo maligna melanoma, the number of dopa-positive cells was usually significantly higher than in the contralateral body side. On the other hand, no difference was generally found around nodular melanoma.
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PMID:Increase of melanocytes around malignant melanoma. 5 8

In malignant melanoma, using Sephadex G-200 chromatography and polyacrylamide gel electrophoresis (PAGE), it has been possible to separate two types of skin reactive antigens. The first, found in Sephadex fraction II and PAGE region a appears specific for melanoma. Allogeneic extracts have produced positive reactions in many patients with skin or ocular melanoma, and have given negative reactions in patients with other types of cancer or in patients with ocular lesions simulating melanoma. The second group of antigens, in Sephadex fraction III and PAGE region b were less specific. These antigens produced positive skin reactions in some patients with breast cancer, as well as in patients with melanoma. Reactivity to PAGE region a appeared to be confined to one protein band, but three different bands in region b gave positive reactions. A study was made of the presence or absence of similar antigens in metastatic deposits of malignant melanoma. Metastatic lesions in the following tissues were analyzed: liver, lung, adrenal, skin, and colon. These were compared with pooled primary skin melanomas by skin testing in the same patients. The tumor-associated melanoma antigen, found in Sephadex fraction II and PAGE region a appeared to be strongest in adrenal, lung, and liver metastases. It was found that the protein yield in this region was not indicative of the strength of the antigen. Therefore, a careful, detailed analysis of the protein bands present in PAGE regions a and b from primary skin melanoma was conducted. Only one band in PAGE region a was found to be responsible for positive skin reactivity. This band was found to be a glycolipoprotein. Further studies were also conducted in order to determine whether or not some of the antigens present might be fetal antigens. Some of the protein bands present in Sephadex fraction III and PAGE region b of melanoma appeared to be similar to some of the PAGE region b proteins present in fetal skin cells. Two bands from fetal skin also had the same location on PAGE as two bands from ductal breast cancer, although the relationship to melanoma region b antigens was not exact. These fetal proteins, which seemed to be present both in ductal breast cancer cell membranes and in melanoma cell membranes, might account for the positive skin reactivity seen in this region, and also for the cross reactivity of skin tests with this antigen.
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PMID:Analysis of soluble melanoma cell membrane antigens in metastatic cells of various organs and further studies of antigens present in primary melanoma. 5 80

The specificity of cell-mediated cytotoxicity against melanoma cells in vitro has been analyzed in a large number of studies with cells both from normal and melanoma subjects. As in a number of other, recent, similar human studies, no evidence for tumour specificity was found. Effector cells in peripheral blood responsible for the cytotoxic raction were examined by cell separation methods based on red cell rosette formation and separation through Hypaque-Ficoll mixtures. The evidence suggests that non-specificity results from killing by cells separating largely in the non-sheep red blood cell rosetting fraction and which have cytotoxic specificity directed broadly to cells with abnormal membranes. Further analysis revealed that the cells were non-phagocytic and did not bear receptors for complement. They appear to be activated into cell division and to bear surface receptors for the Fc portion of IgG. Additional evidence is presented suggesting that the cells mainly responsible are activated thymus-dependent cells present in the circulation of both tumour-bearing and normal subjects.
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PMID:Specificity of cell-mediated cytotoxicity against human melanoma lines: evidence for "non-specific" killing by activated T-cells. 5 32

A microcytotoxicity technique was used to determine the sequential in vitro reactivity against melanoma cells of lymphocytes from melanoma patients receiving immunotherapy and from healthy donors. Lymphocytes were collected 2 weeks for 2-3 months and were stored in liquid nitrogen until use. Preliminary studies had indicated that freezing did not effect the reactivity of lymphocytes. Lymphocytes from 10 healthy donors tested against melanoma cells exhibited substantial reactivity which showed no consistent pattern over time. Lymphocytes from 9 melanoma patients exhibited increased reactivity after immunotherapy. Patterns of reactivity against melanoma cells and against bladder carcinoma cells were similar, indicating lack of specificity for melanoma antigens. Correlations with clinical course of the disease were not apparent.
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PMID:Sequential in vitro reactivity of lymphocytes from melanoma patients receiving immunotherapy compared with the reactivity of lymphocytes from healthy donors. 5 35

The leukocyte adherence inhibition (LAI) test has been used to assess specific anti-tumour immunoreactivity in 80 patients with malignant melanoma, 21 of whom had apparently been successfully treated by surgery, and 44 control subjects. Reaction with melanoma extracts in vitro enabled the activity of blood leukocytes to be detected by inhibition of their adherence to glass, while serum was tested for factors which modified this inhibition. Of the patients with tumours (ranging from primary melanoma in situ to advanced disseminated disease), 22/24 had active leukocytes and 50/58 has serum blocking factor; two of the sera, from patients with regressing tumours were unblocking. After surgery with no clinical recurrence, leukocytes continued to be active except when tested several years after operation. Blocking factor rapidly disappeared in 16/20 patients tested, and in several patients examined serially the serum became unblocking. In three cases, persistence of serum blocking was followed by clinical diagnosis of metastases. Leukocyte activity was nerver detected in control subjects (0/10), many of whom had other kinds of tumours or skin lesions. Blocking activity in serum was found in only 3/38 controls with no history of melanoma (1 had a fibrosing cellular blue naevus and 2 had liver disease). Thus the LAI test correlated well with clinical and pathological findings, and shows great promise for the reliable, rapid and specific immunodiagnosis of malignant melanoma.
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PMID:Leukocyte adherence inhibition and specific immunoreactivity in malignant melanoma. 5 36

A high-molecular-weight RNA encapsulated with an RNA-instructed DNA polymerase in particles possessing the density characteristic of the RNA tumor viruses has been detected in 13 out of 14 human malignant melanomas. The [3H]DNA synthesized by these particles in an endogenous reaction hybridizes to RNA extracted from the human melanoma particulate structures, but not to RNA from normal skin. Similar particles containing RNA and enzyme have been found in basal cell and squamous cell carcinomas of the skin. The RNA of the melanoma particles is easily distinguishable by hybridization from the RNAs found in the particles of the basal and squamous cell carcinomas.
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PMID:Oncornavirus-like particles in human skin cancers. 5 74

B-16 melanoma cells were synchronized for G1-S periods by mitotic shake-off and S-G2 periods by thymidine block. The surface morphology of the B-16 melanoma at low density partially confluent culures revealed that, as in other cell systems investigated, the surface morphology could be correlated with four periods to cell cycle: G1, S, G2 and M. G1 cells were rounded and possessed microvilli, blebs and ruffles (late G1). During S period, blebs and microvilli diminished and disappeared, but ruffles were more evident. Late G2 cells acquired microvilli, surface blebs, and extended filopodia and began to thicken and round themselves for mitosis.
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PMID:Alteration in the surface morphology of synchronized B-16 melanoma cell during the cell cycle. 5 66

Urinary excretion of 5-S-cysteinyldopa was studied in 9 patients with primary melanoma. All had 5-S-cysteinyldopa excretion in the normal range. In 8 of the patients excretion values decreased after removal of the tumour. Twenty-four patients with clinical signs of melanoma metastasis were examined for 5-S-cysteinyldopa and dopa+dopamine in the urine. 16 of the 24 had pathologically increased excretion of 5-S-cysteinyldopa and 7 of the 24 had pathological excretion of dopa+dopamine. Six of the latter belonged to the group with increased 5-S-cysteinyldopa excretion and one patient had a borderline value of 5-S-cysteinyldopa. Determination of 5-S-cysteinyldopa seems to be of value in the follow-up of patients operated on for primary melanoma.
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PMID:Urinary excretion of 5-S-cysteinyldopa in patients with primary melanoma or melanoma metastasis. 5 67

The possibility of using affinity chromatography for the purification of tyrosinase was explored. When purified mushroom tyrosinase was employed, almost all tyrosinase became bound to Sepharose containing 3-iodotyrosine, an inhibitor of tyrosinase. When crude extracts from B16 melanoma were employed, partial purification of tyrosinase and separation of two or possibly three forms of tyrosinase could be obtained. The results indicate that affinity chromatography could possibly be employed for the purification of tyrosinase during the final stages of the purification procedures.
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PMID:Use of affinity chromatography for purification of tyrosinase. 5 68

The results of radionuclide scans (liver, bone, and brain scans and whole-body scans using bleomycin tagged with radioactive indium [111In]) performed on 100 melanoma patients during their initial evaluation were reviewed to determined whether or not they effected a change in clinical staging or therapeutic decision. Patients were classified as stage I (primary disease) or stage II (regional disease) on the basis of regional lymph node dissections. Only one patient (stage II) of 73 stage I and II patients had an abnormal finding on the initial radionuclide scan. Fifteen of 26 patients thought to be stage III (disseminated disease) on clinical grounds had abnormal findings on at least one scan. A therapeutic change as a result of scanning occurred in the stage II patient after abnormal bone and whole-body scans. As an initial routine screening test for stage I and II melanoma patients, radionuclide scanning was unproductive and rarely influenced therapeutic decisions.
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PMID:Radionuclide photoscanning. Usefulness in preoperative evaluation of melanoma patients. 5 41


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