Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027627 (metastases)
103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A spontaneous, hypomelanotic variant (MI) of the highly melanotic transplantable hamster melanoma of Bomirski (Ma) is the subject of this report. Tyrosinase activity is 2-3 times higher, but melanin content significantly lower than in the parental Ma melanotic melanoma. Acid phosphatase activity is similar in both, but beta-glucuronidase and aryl-sulfatase A are 2-3 times higher in the hypomelanotic variant. Transplanted MI melanomas grow more slowly than the parental tumor, but metastasize with similar incidence and localization. Hypomelanotic variant melanoma cells, even those in grossly nonnecrotic parts of the transplants, show signs of low viability like swelling of the cytoplasm or cellular condensation, and disintegration. Autophagic vacuoles are numerous. They appear to be formed by enclosure of a portion of cytoplasm by cisternae of smooth endoplasmic reticulum or trans-Golgi network. These limiting cisternae contain tyrosinase as evidenced by deposition of electron dense reaction product on incubation with tyrosine or DOPA. Other sites of ultrastructural tyrosinase reaction are melanosomes and the smooth-surfaced cisternae and vesicles of the trans-Golgi network. We postulate the low cell viability, associated with autophagosome formation, is the cause for the growth retardation of the MI variant, and that the lower melanin content of these tyrosinase-rich cells is due to sequestration of a substantial portion of newly synthesized enzyme into autophagic vacuoles before it has the chance of being incorporated into melanosomes.
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PMID:Pathology and ultrastructural characteristics of a hypomelanotic variant of transplantable hamster melanoma with elevated tyrosinase activity. 311 4

Epidemiological and experimental investigations have led to the hypothesis that the growth of malignant melanoma is induced by hormones. The demonstration of free-hormone binding sites in melanoma tissue may help to determine the validity of this hypothesis, as receptors are necessary for the transformation of hormonal action. The DCC assay with subsequent saturation analysis was used for the demonstration of specific cytoplasmatic binding sites of steroid hormones. The presence of free-cytosolic estrogen-, progesterone- and glucocorticosteroid receptors was investigated in 50 melanoma samples from 46 patients. In 20 of the 50 specimens, free estrogen and progesterone receptors were found. Free-glucocorticosteroid receptors we found in 10 cases. The use of four fold-labeled estradiol (2,4,6,7-[3]-17 beta-estradiol) in the DCC assay produced a false-positive demonstration of free-estrogen receptors. Tyrosinase hydroxylates estradiol at the C2 level of the steroid. Using fourfold labeled estradiol, tritium is separated at the C2 position, thus forming radioactive water in the cytosol which mimics high, free-estrogen binding sites. The use of twofold-labeled estradiol or L-dopa in the experiments with fourfold labeled estradiol produced no false-positive determinations of estrogen receptors. The demonstration of receptors in malignant melanomas was unaffected by the sex of the patient. Also, the type of malignant melanoma, the invasion level, and the prognostic index did not show a correlation with the presence of the various hormone receptors. In metastases, free steroid hormone receptors were detected less often than in the primary tumor.
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PMID:[Steroid receptors in malignant melanomas]. 393 Apr 22

Peptide specificity of cultured tumor-infiltrating lymphocytes (TIL) was systematically investigated in a group of HLA-A2.1+ metastatic melanoma patients consecutively referred to our department for surgical treatment. Seven samples from 6 patients were studied. All surgical specimens showed evidence of gp 100, MART-1/Melan-A and Tyrosinase gene expression as detectable by reverse PCR (rPCR). Cultured TIL from 2 patients displayed cytotoxic activity against autologous or HLA-matched EBV-transformed cells previously pulsed with MART-1/Melan-A27-35 peptide. In contrast, no CTL activity against gp100(280-288) or tyrosinase1-9 peptides could be observed. TIL were then repeatedly stimulated in vitro with the same peptides. After 6 restimulation courses at weekly intervals, specific recognition of gp100(280-288) and MART-1/Melan-A peptides was detectable in 3 and 5 TIL populations, respectively. In one case Tyrosinase1-9-specific CTL could be demonstrated. Two TIL populations from metastases resected from a melanoma patient at 6 months' distance showed a different peptide specificity pattern, and no specific CTL could be generated from simultaneously sampled peripheral blood mononuclear cells (PBMC). All peptide-specific CTL populations also displayed significant cytotoxic activity against HLA-A2.1 matched melanoma cell lines expressing the antigens under investigation. Our data indicate that CTL specific for MART-Melan-A27-35, gp100(280-288) or Tyrosinase1-9 peptides could be expanded with varying frequency from TIL derived from 4 out of 6 HLA-A2.1+ patients whose tumors expressed the genes encoding these tumor-associated antigens (TAA).
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PMID:Peptide-specific CTL in tumor infiltrating lymphocytes from metastatic melanomas expressing MART-1/Melan-A, gp100 and Tyrosinase genes: a study in an unselected group of HLA-A2.1-positive patients. 759 2

Patients with malignant melanoma and distant metastases generally have an unfavorable prognosis, with a median survival of about 6 months. The mechanisms of hematogenous spread and implantation of melanoma cells are, however, poorly understood, because the standard diagnostic methods are not sensitive enough to detect oligocellular micrometastases. Recently a method using reverse transcription and polymerase chain reaction to determine tyrosinase mRNA in peripheral blood, which indicates the presence of circulating melanoma cells, has been developed. We utilized this assay to examine blood samples of 56 patients with malignant melanoma in different stages of disease. In one of 10 patients in stage I (localized disease) and in six of 17 patients with regional lymph nodes metastases (stage II) tyrosinase mRNA was detected. Tyrosinase transcripts were found in all 29 patients with distant metastases (stage III). Interestingly, tyrosinase mRNA was also detected in six patients with metastatic amelanotic malignant melanoma. In contrast, tyrosinase mRNA was not detectable in any of 39 healthy subjects or 17 patients with other malignancies. These findings may be helpful to define a patient group at high risk for systemic spread of disease.
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PMID:Hematogenous spread of malignant melanoma cells in different stages of disease. 824 18

Tyrosinase mRNA produced by melanoma cells can be detected by reverse transcriptase-polymerase chain reaction (rt-pcr) with fine-needle tissue punctures. Fine-needle punctures from six suspected skin and lymph node metastases in three patients with malignant melanoma were analysed via rt-pcr for tyrosinase mRNA. All the suspected metastases were surgically removed and histologically examined separately. In each case the rt-pcr results and the histological diagnosis corresponded. This less invasive and highly sensitive method could prove to be a useful alternative in the diagnosis of melanoma metastasis.
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PMID:[Detection of tyrosinase mRNA using reverse transcription/polymerase chain reaction with fine needle punctures of melanoma metastases]. 864 2

In recent years, it has become evident that T cells can recognize peptides of melanocytic lineage antigens such as gp100, MART-1, and tyrosinase at the tumor cell surface and can subsequently destroy these cells. It is thus feasible to develop immunotherapeutic approaches based on the melanocytic marker profiles of melanoma cells. One of the predictors of the success rate of such a treatment is the extent of positive (target) tumor cells within the lesions of the patient. First, we investigated the presence of these three proteins in 18 human melanoma cell lines using RT-PCR and immunohistochemistry. In 11 cell lines, mRNA and protein of all three markers could be detected; in one cell line, only two markers were present, and six melanoma cell lines showed no evidence for these markers. Secondly, we stained frozen sections of 105 human melanocytic lesions, 13 common nevocellular nevi, 13 atypical nevi, 13 early primary melanomas (Breslow < 1.5 mm), 25 advanced primary melanomas (aPM; Breslow > or =1.5 mm), and 41 melanoma metastases (MM) with antibodies against glycoprotein 100, melanoma antigen recognized by T cells, and tyrosinase. In addition, we used the 3,4-dihydroxy-L-phenylalanine reaction to detect tyrosinase enzyme activity as a confirmation of the tyrosinase immunohistochemical results in a subset of the lesions. In the benign lesions, glycoprotein 100 was more prominently expressed in epidermal melanocytes, whereas melanoma antigen recognized by T cells was encountered in all or nearly all dermal melanocytes in all nevocellular nevi and atypical nevus lesions. Tyrosinase was found in a lower percentage of melanocytes, both in the epidermis and in the dermis within these lesions. With regard to heterogeneity of staining within the malignant lesions, we found that 54% (early primary melanomas), 48% (aPMs), and 56% (MM) of the lesions stained within the same staining category for all three proteins studied. Approximately 17% of the aPM and MM lesions did not show positive tumor cells for any of the three proteins. We conclude that a subgroup of patients with high expression should be selected for immunotherapeutic treatment approaches based on the presence of these proteins.
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PMID:Heterogeneous expression of immunotherapy candidate proteins gp100, MART-1, and tyrosinase in human melanoma cell lines and in human melanocytic lesions. 924 53

Human melanoma cells express several antigens which are recognized by autologous and specific CTL clones in association with HLA-class-I molecules. Many of these antigens represent suitable targets for tumor immunotherapy, since their expression in human melanoma cells is common and highly specific. In order to achieve real clinical success with therapeutic vaccination strategies, one important requirement is the expression of the target antigen by all the tumor lesions of a patient. We have studied this issue by assessing, through an RT-PCR approach, the expression of MAGE-1, MAGE-2, MAGE-3, BAGE, GAGE-1/2, Tyrosinase and Melan-A/MART-1 genes in 17 clusters of simultaneous in-transit or regional lymph-node metastases collected from 15 stage-III and 1 stage-IV (AJCC/UICC pTNM system) melanoma patients. In 14 out of 17 clusters of simultaneous metastatic lesions (82%), the homogeneity in the pattern of gene expression within the cluster was complete. Heterogeneity within the same cluster was observed in only 3 out of 17 clusters (18%) and represented only minor features. Our data reveal that, in AJCC-stage-III melanoma patients, different but simultaneous metastatic lesions express the same pattern of antigen-coding genes. These observations have 2 main clinical implications: (i) the antigenic characterization of one single and easily accessible lesion allows identification of optimal targets for an active antigen-specific immunotherapy treatment; (ii) almost all the metastatic lesions are expected to be hit by the immune response eventually induced against the tumor antigen. Moreover, these data suggest that active specific immunotherapy directed against MAGE-1, MAGE-3, BAGE, GAGE-1/2, Melan-A/MART-1 and Tyrosinase antigens could be exploited as an adjuvant treatment to surgery in high-risk AJCC-stage-III-melanoma patients.
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PMID:High homogeneity of MAGE, BAGE, GAGE, tyrosinase and Melan-A/MART-1 gene expression in clusters of multiple simultaneous metastases of human melanoma: implications for protocol design of therapeutic antigen-specific vaccination strategies. 965 May 52

Detection of melanoma cells in the peripheral blood has been facilitated by the reverse transcriptase-polymerase chain reaction (RT-PCR), but their presence is of uncertain importance in the evolution of the disease. We studied the detection of melanoma cells using RT-PCR in the peripheral blood of 21 patients, four with regional lymph node metastases (American Joint Committee on Cancer [AJCC] stage III) and 17 with disseminated disease (AJCC stage IV). RNA was extracted from 10 ml of heparinized blood following density gradient centrifugation and converted into cDNA for PCR analysis. Assay sensitivity of 10 cells in 10(7) mononuclear cells and granulocytes obtained from 10 ml of peripheral blood was achieved using the G361 and C32 melanoma cell lines. Tyrosinase mRNA was not detected in control samples from healthy volunteers or patients with non-malignant disease. Six patients (one stage III, five stage IV) tested positive for tyrosinase mRNA (28.6%); with one exception, all patients were receiving chemotherapy at the time of sampling. Of the six positive results, three were from patients who initially tested negative but were subsequently positive after a 3-4 week interval. The low detection rates of melanoma cells in the peripheral blood of patients with widely disseminated disease is consistent with recent reports and correlates poorly with the clinical stage of melanoma. This may be partly explained by the clinically observed intermittent and random evolution of melanoma metastases.
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PMID:Detection of tyrosinase mRNA by RT-PCR in the peripheral blood of patients with advanced metastatic melanoma. 1050 59

The aim of our study was to investigate the metastatic pathways of melanoma cells in sentinel and other regional lymph nodes. The term "sentinel lymph node" means that the first lymph node of the draining site of a primary tumor is never bypassed in malignant melanoma. In this case lymph node dissection would be necessary only when melanoma cells are detected in the sentinel node. Tyrosinase reverse transcriptase-polymerase chain reaction was applied to search for metastatic melanoma in the sentinel lymph node and in further lymph nodes of a complete lymph node basin in patients who underwent lymph node dissection. In 24 patients with malignant melanoma the draining site of the tumor was marked by lymphoscintigraphy and by intraoperative injection of patent blue V in the area around the primary tumor. The lymph nodes of the affected basin were excised and prepared for histopathologic, immunohistochemical, and molecular biologic examinations. Regarding the sentinel lymph node, 10 of 24 patients showed morphologic evidence for metastases, three additional patients showed only tyrosinase transcripts. In 11 of these 13 cases we found one or more nonsentinel lymph nodes with morphologically detectable melanoma cells and/or tyrosinase mRNA. Interestingly, in seven of 24 patients a positive tyrosinase reverse transcriptase-polymerase chain reaction was received in nonsentinel lymph nodes, whereas the sentinel lymph node was negative, not only for all histologic examinations but also by tyrosinase reverse transcriptase-polymerase chain reaction. In five of seven patients of the latter group, gp100 reverse transcriptase-polymerase chain reaction was carried out, showing also gp100 mRNA in nonsentinel lymph nodes only. Our data indicate that the concept of the sentinel lymph node may miss micrometastases. Whether such micrometastases cause a recurrence or a metastasis of malignant melanoma, or can be destroyed by the immune system, remains to be clarified.
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PMID:Detection of melanoma micrometastases in the sentinel lymph node and in nonsentinel nodes by tyrosinase polymerase chain reaction. 1050 40

Malignant melanomas of the vagina are rare tumors. In this study we present the clinicopathologic features and immunohistochemical analysis of 26 such cases seen in our institution over a period of 30 years. The patients' age ranged from 38 to 90 years (mean 60 years); three patients were premenopausal. Ethnicity was known in 24 patients: 20 white, 2 hispanic, 1 black, and 1 Asian. The most common presenting symptom was vaginal bleeding, followed by vaginal mass. Grossly, the tumor was polypoid-nodular in the majority of cases. The neoplastic cells were epithelioid in 15 cases and spindled in three cases; eight cases had both cell types. Vascular-lymphatic invasion was seen in six cases and perineural invasion was seen in four cases. S-100 was strongly and diffusely positive in 25 of 26 cases (96%). HMB-45 was strongly positive in 16 (62%), 3 (11%) were focally positive, 1 case showed a rare positive cell, and 6 (23%) were negative. With MART-1, 20 cases (77%) were strongly positive, 1 (4%) showed a rare weakly positive cell, and 5 (19%) were negative. Twenty-one cases (81%) expressed tyrosinase and 20 (77%) expressed microphthalmia transcription factor. Twenty cases were Chung's level IV, 3 were level III, and 2 were level II. The patients were treated as follows: anterior exenteration with or without lymph node dissection and with or without radiotherapy (RT) or chemotherapy (CT) (7 cases), wide local excision with or without lymph node dissection and RT/CT (10 cases), hysterectomy with vaginectomy with or without RT/CT (3 cases), vaginectomy with RT (1 case), RT (1 case), and RT and CT (1 case). One patient had palliative RT for the brain metastasis only. Follow-up was available in 23 patients ranging from 3 to 276 months (median 18 months). Local recurrence after primary treatment was seen in six patients and distant metastases in 11 patients. Fifteen patients died of the disease (3-83 months), 4 have no evidence of disease (5-24 months), and 4 are alive with disease (6-276 months). This study confirms the poor prognosis of patients with vaginal melanoma. S-100 remains the most sensitive marker for these tumors. HMB-45 is negative in 23% cases of vaginal melanoma. Tyrosinase and MART-1 are useful markers when S-100 is negative or only focally positive.
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PMID:Vaginal melanoma: a clinicopathologic and immunohistochemical study of 26 cases. 1240 21


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