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)

NKI/C-3 and NKI/black-13 are monoclonal antibodies recognizing different epitopes on a melanoma-associated antigen that is preserved after fixation in formalin and embedding in paraffin in virtually all melanoma tissues. The antigen, a predominantly cytoplasmic vesicle membrane-bound heterogeneous glycoprotein of 25-110 X 10(3) daltons, was shown to be a single 25 X 10(3) dalton polypeptide when incorporation of N-linked carbohydrates was inhibited by tunicamycin. The antigen was measured in a double determinant enzyme immunoassay (DDEIA) using NKI/C-3 as catcher antibody. Results from in vitro experiments indicated that the antigen is actively shed from living cells. In sera from melanoma patients with a small tumor burden, the antigen concentrations were in the range of those of controls (0-22 U/ml). Significantly increased values (33-600 U/ml) were found in sera from patients with a moderate or large tumor burden. The antigen concentrations in sera from patients with multiple metastases of other tumors were within the range of controls. Several sera from patients with multiple metastases of colon, pancreatic, and stomach carcinoma, however, contained increased antigen concentrations (45-80 U/ml). These results correspond with the reactions of NKI/C-3 in tissue sections of some malignancies other than melanoma. During the follow-up of melanoma patients the concentrations of circulating antigen correlated with tumor progression. The predictive value of the NKI/C-3 assay was no better than determination of serum lactate dehydrogenase, alkaline phosphatase or gamma glutamyl transferase activity.
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PMID:Circulating melanoma-associated antigen detected by monoclonal antibody NKI/C-3. 243 Jul 6

The immunoprofiles of 121 germ cell and trophoblastic neoplasms were defined, using a battery of antibodies against cytokeratin (CK), vimentin (VIM), epithelial membrane antigen (EMA), placental alkaline phosphatase (PLAP), S-100 protein, leukocyte common antigen (LCA), UCHL-1, LN-2, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), chromogranin A, Leu-7, alpha-fetoprotein (AFP), alpha-1-antitrypsin (AAT), and the beta subunit of human chorionic gonadotropin (BHCG). In addition to 85 neoplasms of testicular origin, the cases included eight ovarian germ cell tumors and 28 extragonadal neoplasms. All tissues had been subjected to formalin fixation and paraffin embedding. Similar immunoreactivity patterns were seen in gonadal and extragonadal neoplasms, gestational and nongestational choriocarcinomas, components of mixed germ cell tumors and their pure counterparts, and metastatic and primary lesions. Placental alkaline phosphatase was a sensitive marker of germ cell differentiation, and expression of this marker in the absence of EMA appeared to be a staining pattern unique to germ cell tumors. Both LCA and S100 were absent in neoplastic germ cells, and thus were useful in differentiating these tumors from malignant lymphoma and malignant melanoma, respectively. Cytokeratin was helpful in distinguishing seminomas/dysgerminomas from nonseminomatous germ cell tumors, although 10% of seminomas showed focal or diffuse cytokeratin reactivity. Finally, 75% of all germ cell neoplasms displayed NSE, calling the specificity of this determinant into question.
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PMID:Immunohistochemistry of germ cell and trophoblastic neoplasms. 245 24

A simple and sensitive chromogenic microtitre plate assay for glycoprotein enzymes is described, using melanoma tissue plasminogen activator (t-PA) as a model enzyme. The assay is based on the binding of t-PA to immobilised lectin and quantitating the bound enzyme with plasminogen, fibrinogen fragments and chromogenic substrate S-2251 on an ELISA plate reader. Seven different lectins were examined for the binding of t-PA, and of these, concanavalin A was chosen for subsequent studies. The specificity of this binding can be inhibited dose-dependently in the presence of D-mannose and methyl alpha-D-mannoside, but not by D-glucose and D-lactose. The lower limit of the sensitivity of this assay is about 0.5 IU/ml. Comparison of the dose-response curves indicates that the sensitivity of this assay method is very similar to that of bioimmunoassay using anti-t-PA IgG to capture the antigen. The applicability of this method to other glycoprotein enzymes was also evaluated using alkaline phosphatase from bovine mucosa. The specificity of this method was related to the choice of substrate and this was shown by analysis of a mixture of t-PA and alkaline phosphatase. It is suggested that this assay can be adapted for the analysis of complex glycoprotein mixtures with the appropriate choice of lectin and substrate.
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PMID:Lectin affinity bioassay: an assay method for glycoprotein enzyme. 249 37

Recently, great interest has been shown in the histological identification of small cell tumours of childhood--nephroblastoma (Wilms' tumour), neuroblastoma, rhabdomyosarcoma and Ewing's sarcoma--using immunohistochemical methods. However, several antigens operationally specific for leucocyte typing in blood and marrow are also expressed on cells of epithelial and neural origin. We undertook phenotypic characterization of 17 non-haemopoietic small cell tumours of childhood using a panel of 30 monoclonal antibodies to leucocyte, epithelial and cytoskeletal antigens using a sensitive alkaline phosphatase-anti-alkaline phosphatase technique on cryostat sections of fresh tumour. Our results demonstrated frequent expression of the leucocyte-associated antigens CD10 (CALLA), CD9 (p24) and CDw32 (FcRII) in these small cell tumours and occasional expression of MHC class II (HLA-DR) and HNK-1 antigens. However, the leucocyte-associated antigens CD45 (leucocyte common), CD22 (pan B-cell), CD11b (C3bi receptor), CD15 (Lewisx) or CDw42 (platelet gp Ib) were not detected on any tumour. Aberrant expression of desmin, neurofilament and UJ13A antigen was found in nephroblastoma and of epithelial-associated markers (CIBr17 and 43-9F) in neuroblastoma. Our results also demonstrated broad reactivity in frozen section with two monoclonal antibodies specific for melanoma (NKI/C-3) or epithelial cells (OM-1) in paraffin sections. Hence, it is necessary to include monoclonal antibodies to CD45 and pan-epithelial antigens, e.g. LP34 (cytokeratin) or HEA125 for the precise immunohistochemical identification of small round cell malignancies of childhood.
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PMID:Phenotypic characterization of non-haemopoietic small cell tumours of childhood with monoclonal antibodies to leucocytes, epithelial cells and cytoskeletal proteins. 254

The proliferation rate of 40 intracranial neoplasms (30 gliomas, 1 hemangioblastoma, 3 meningiomas, 1 neurinoma and 5 brain metastases) was investigated using the monoclonal antibody Ki-67. In eleven of the gliomas recurrences could be observed, and two of them recurred for second time. In total the Ki-67 labelling indices of 53 specimens were investigated. The Ki-67 nuclear antigen was demonstrated in frozen sections by application of the appropriate monoclonal antibodies according to a modified alkaline phosphatase-antialkaline phosphatase (APAAP) technique. The proliferation rate was evaluated by cell count calculation of the staining index. Ki-67-labelled glioma cells varied from 0.2 percent in one meningioma (WHO-grade I) to 9.1 percent in one glioblastoma. In ten glioma recurrences, higher Ki-67 staining indices could be observed than in their primaries, even when the histological grading did not change substantially. In a cerebellar hemangioblastoma, a trigeminal neurinoma and two endotheliomatous meningiomas the fraction of stained nuclei was less than one percent; however, one recurrent transitional meningioma without any histological sign of malignancy showed a staining index of 2.4 percent. The staining indices of five brain metastases of different malignancies ranged from 1.5 percent in a malignant melanoma to 6.1 percent in bronchial carcinoma. In the majority of the cases examined, the percentage of Ki-67 labelled cells was in accordance with the histologic grade of the neoplasm. In general, there was a direct relationship between the number of stained nuclei and the frequency of mitoses (mitotic index) evaluated in hematoxylin-eosin stained frozen sections. Interestingly, the frequency of mitosis and stained nuclei were higher in tumor recurrences than in the primaries. The results of this study imply that immunohistological labelling of the proliferating cell fraction should become an important additional criterion to predict the biological behaviour of human nervous system neoplasms.
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PMID:Relationship between Ki-67 positive cells, growth rate and histological type of human intracranial tumors. 305 45

A new class of compounds, termed "dopa phosphates," is described. The compounds contain phosphate ester linkages at positions 3 and/or 4 of the phenylalanine ring. Dopa phosphates are highly soluble compounds which are stable over a wide range of pH values and are not hydrolyzed by boiling in concentrated acid. Synthetic yields of greater than 90% can be obtained using dopa as starting material. Exposure to alkaline phosphatase results in hydrolysis of the phosphate moieties and production of dopa. Dopa phosphates do not inhibit dopa oxidase (tyrosinase, EC 1.14.18.1) activity. Dopa oxidase does not catalyze the conversion of dopa phosphates into melanin unless the dopa phosphates are first treated with alkaline phosphatase. Dopa phosphates, when compared to L-dopa, are stable in the presence of O2 and are not oxidized by serum proteins. In the presence of cultured melanoma cells, dopa phosphates are readily converted into melanin, indicating that the cells are able to produce dopa from dopa phosphates. At high concentrations, dopa phosphates are cytotoxic toward melanoma cells in culture. The cytotoxicity is enhanced at least 3-fold by pretreatment of cells with melanotropin and is prevented by phenylthiourea, an inhibitor of dopa oxidase activity. These results, combined with studies on the uptake of radioactive forms of dopa phosphates (32P and 14C), indicate that phosphorylated isomers of dopa are efficiently taken up by Cloudman melanoma cells and are readily converted by the cells into a melanin precursor, presumably L-dopa.
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PMID:Increase in melanin formation and promotion of cytotoxicity in cultured melanoma cells caused by phosphorylated isomers of L-dopa. 307 62

The immunological phenotypes of the lymphoid cells in 39 cutaneous malignant melanomas have been investigated by staining cryostat sections with a panel of 20 monoclonal antibodies against lymphoid cells and their subsets. Staining was performed by the alkaline phosphatase: anti-alkaline phosphatase (APAAP) method in which the substrate label (red) is easily distinguishable from melanin. The lymphoid infiltrates had an essentially identical composition in all cases, consisting of T-lymphocytes associated with both Langerhans cells and HLA-DR-positive tissue macrophages. B-lymphocytes and natural killer cells were either absent or only present in low numbers. The ratio between T8 (suppressor/cytotoxic) and T4 (helper/inducer) lymphocytes varied and showed no correlation with melanoma subtype, level of invasion or magnitude of lymphocytic response. Examination for markers associated with T-cell activation and/or with cell proliferation revealed that all lesions contained HLA-DR-positive T-lymphocytes, whereas expression of the transferrin receptor and the interleukin-2 receptor (Tac-antigen) occurred mainly in melanomas with a significant inflammatory infiltrate. These data support the concept that malignant melanomas are capable of evoking autologous T-cell immune reactions.
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PMID:Immunohistological analysis of the lymphoid infiltrate in cutaneous malignant melanomas. 310 Dec 84

Liver scintigraphy (99Tcm sulphur colloid) was performed in 118 patients with malignant melanoma. In 73 patients diagnosed as stage I, the pretreatment evaluation showed one false-negative and one false-positive examination. During follow-up there were ten abnormal liver scintigraphies; one was later correlated to liver metastases. In 46 patients diagnosed as stage II-IV, the pretreatment liver scintigraphy yielded false-negative results in 36% and false-positive results in 15%. The predictive values of positive and negative tests were 44% and 81%, respectively. The yields of liver tests (S-alkaline phosphatase, S-gamma-glutamyl-transferase) in patients with liver metastases were low. This study demonstrated the limitations of liver scintigraphy for diagnosis of liver metastases in patients with malignant melanoma.
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PMID:Value of liver scintigraphy in pretreatment staging and in follow-up of patients with malignant melanoma. 399 Mar 6

Treatment of mammalian cells in culture with retinoic acid causes a time- and concentration-dependent increase of the specific activity of alkaline phosphatase. The increase reaches a factor of 15 and more and begins at a concentration of 10(-8)M retinoic acid. The induction is inhibited by cycloheximide or actinomycin D. The same isoenzyme of alkaline phosphatase is expressed in control and in retinoic acid-treated cells as demonstrated by the inhibitions by amino acids and peptides. The enzyme induction occurs in rat heart, skeletal muscle, brain, lung cells and HeLa cells. No induction was found in two lines of human melanoma cells. After treatment of cells with tunicamycin, the induction of alkaline phosphatase is detectable only in the homogenate and no longer detectable by histochemical methods. This shows that the glycosylation of the protein is an important step in the insertion of this enzyme into the plasma membrane.
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PMID:[Induction of alkaline phosphatase by retinoic acid]. 400 46

In Sinclair swine, there is an increase in alkaline phosphatase activity in spontaneously arising melanoma tumors when compared to normal skin. While alkaline phosphatase activity could be detected in melanomas from animals 1 day old, the maximum levels of alkaline phosphatase activity occurred in tumors from animals greater than 30 days old. The alkaline phosphatase was purified from cutaneous melanomas using chloroform precipitation, Phenyl-Sepharose chromatography, and concanavalin A Sepharose chromatography approximately 146-fold, with an overall recovery of 15%. The purified enzyme exhibited optimal activity over the pH range of 8.9-10.6. The apparent Km of the enzyme for p-nitrophenyl phosphate was 0.15 mM. The enzyme exhibited a relative mobility of 0.04 in nondenaturing polyacrylamide gels. The molecular weight of the enzyme was estimated by gel filtration chromatography to be 122,000 and it was composed of two identical subunits each having a molecular weight of 67,000. The enzyme was thermolabile at 56 degrees C (T50, 18 min) and its activity was inhibited by L-homoarginine, levamisole, and vanadate, but not by L-phenylalanine or L-phenylalanylglycylglycine. These characteristics distinguished the enzyme from the intestinal isoenzyme that is found in normal swine skin but were similar to those exhibited by the porcine placental isoenzyme of alkaline phosphatase. These results suggest that the development of malignant melanoma in Sinclair swine is accompanied by the expression of a placental-like alkaline phosphatase activity.
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PMID:Properties of an alkaline phosphatase from Sinclair swine melanoma. 651 73


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