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)

Malignant cutaneous melanomas and metastases were taken directly from in situ lesions of genetically identical (C57BL/6 strain) Tyr-SV40E transgenic mice, and samples were analyzed by Western immunoblotting with antisera specific for the COOH terminus of each of four melanocytic proteins. These were tyrosinase, TRP-1, TRP-2, and Pmel 17/silver. Of the 13 melanomas examined, there were 5 melanotic primary tumors, 5 amelanotic primary tumors, and 3 amelanotic metastases. The melanotic tumors expressed all of the markers to some extent. In contrast, the amelanotic tumors lacked detectable levels of one, two, or three of the proteins, except for an apparently amelanotic tumor sample in which all were expressed, but in which some melanotic cells were likely to have been present. Thus, despite some variability, there is clearly a downward trend in the presence of these proteins as the tumors become amelanotic, a pigmentary change associated with ongoing malignant progression. In the amelanotic tumors, tyrosinase was most often deficient, whereas TRP-2 was most often persistently expressed. These results, obtained from melanomas of syngeneic origin, indicate that tumors in the relatively early stages of malignancy might be more responsive than later-stage tumors to immunotherapy involving an ensemble of antigenic peptides of the tested gene products. Moreover, TRP-2 peptides may be especially useful for therapeutic intervention at the later stages.
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PMID:Comparative decreases in tyrosinase, TRP-1, TRP-2, and Pmel 17/silver antigenic proteins from melanotic to amelanotic stages of syngeneic mouse cutaneous melanomas and metastases. 953 58

The presence of regional lymph node metastases is one of the most significant prognostic factors for predicting survival in patients with clinical stage I or II cutaneous melanoma. For accurate staging of the primary tumor a sensitive technique is required to detect occult nodal micrometastases. This prospective diagnostic study was designed to evaluate the incidence of nodal micrometastases using nested reverse transcription-polymerase chain reaction (RT-PCR) for tyrosinase in comparison to immunohistochemical examination. Furthermore, the incidence of melanoma micrometastases detected by RT-PCR was analysed in correlation to major prognostic factors. A total of 466 regional lymph nodes from 79 patients with primary cutaneous melanoma (tumor thickness > 0.75 mm) were investigated. In 49 lymph nodes from 31 patients immunohistochemistry demonstrated melanoma metastases. Using tyrosinase RT-PCR, nodal micrometastases were detected in 136 lymph nodes from 52 patients including all lymph nodes positive by immunohistochemical examination. Out of the 417 lymph nodes negative by immunohistochemistry, 87 nodes (21%) were identified to express tyrosinase by the RT-PCR technique. Among the 48 patients negative by immunohistochemical assessment, 21 (44%) had nodal micrometastases (n = 40) using RT-PCR. All 68 lymph nodes from 46 non-melanoma patients serving as negative controls for tyrosinase RT-PCR were negative. The detection of melanocytic nodal micrometastases by tyrosinase RT-PCR is a highly specific method with a sensitivity significantly higher than that achieved by immunohistochemistry (p < 0.0001). Patients with nodal micrometastases identified exclusively by RT-PCR had significantly higher tumor thickness as compared to patients with negative results by RT-PCR (p < 0.01).
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PMID:Lymph node micrometastases of cutaneous melanoma: increased sensitivity of molecular diagnosis in comparison to immunohistochemistry. 969 21

The authors retrospectively tested the potential value of paraffin-reactive monoclonal antibodies (A103 against melan-A, T311 against tyrosinase) and antibody KBA62 as immunohistochemical markers for amelanotic metastatic melanomas. The study cases included 72 amelanotic metastases of known cutaneous melanomas, 59 poorly differentiated carcinomas, 73 sarcomas of varying histogenesis, 4 Leydig cell tumors, 10 high-grade lymphomas, and 6 plasmoblastic/anaplastic myelomas. The results were compared with immunostainings for S-100 protein and HMB-45. HMB-45, antimelan-A, and antityrosinase showed almost identical staining results, with a sensitivity of 0.85 for HMB-45 and of 0.86 for both antimelan-A and for antityrosinase. HMB-45 and antityrosinase both had a specificity of 1.00; the specificity of antimelan-A was 0.95 as a result of a positive reaction in three of three adrenocortical carcinomas and four of four Leydig cell tumors. KBA62 stainings resulted in a sensitivity of 0.86 for melanomas. A positive immunoreactivity of KBA62 alone had a specificity of only 0.83, but in conjunction with anti-S-100 protein (sensitivity, 1.00; specificity, 0.87) and anticytokeratin 8/18/19 (CK), a KBA62+/S-100+/CK- immunophenotype identified all except one of the melanoma cases that were negative for the three melanocyte-specific markers with a specificity of 0.99. In conclusion, we found comparable immunohistochemical sensitivities of HMB-45, antityrosinase, and antimelan-A for a highly specific identification of approximately 85% of amelanotic metastatic melanomas on paraffin sections. Melanomas that were negative for all of these specific markers might be sensitively and specifically detected with anti-S-100 protein and KBA62.
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PMID:Tyrosinase, melan-A, and KBA62 as markers for the immunohistochemical identification of metastatic amelanotic melanomas on paraffin sections. 972 May 2

Expression of HLA class I molecules is essential for the recognition of tumor cells by CD8+ T cells. In this study, 48 bioptic samples of 42 patients in all stages of melanoma were investigated after short-time cultivation of tumor cells. To confirm melanocytic origin of cultured cells, samples were screened for mRNA expression of melanoma markers gp100, tyrosinase, MAGE-3, MelanA, and MUC18 by reverse transcriptase-polymerase chain reaction. Surface expression of specific HLA-A and -B allospecificities on melanoma cells were analyzed with a standard microcytotoxicity assay after stimulation with interferon (IFN)-alpha and compared with the background found in peripheral blood mononuclear cells from the corresponding patients. Immunohistochemistry and flow cytometry confirmed specific losses in cases where the appropriate monoclonal antibodies were available. The level of expression of HLA-I, HLA-II, and intercellular adhesion molecule 1 antigens on melanoma cells cultured in the presence or absence of IFN-alpha and IFN-gamma was determined cytofluorometrically. All cell cultures tested were found to be positive for one or more melanocytic markers by reverse transcriptase-polymerase chain reaction. The specific HLA-I alleles on the cultured cells were detectable in 45 of 48 samples. In 11 cases a specific loss of one HLA-I allele was observed (2 x A2, B7, B8, B18, 4XB44, B47, B49). Ten of these samples were derived from locoregional lymphnode metastases or from distant metastatic tumors. Only one sample from a primary melanoma showed a specific loss of HLA-I (B47). IFN-alpha upregulated expression of HLA-I up to 4-fold. IFN-gamma enhanced the appearance of HLA-II up to 35-fold and the expression of intercellular adhesion molecule 1 up to 40-fold. Selective loss of HLA-I allospecificities might be a major step in tumor progression.
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PMID:Higher frequency of selective losses of HLA-A and -B allospecificities in metastasis than in primary melanoma lesions. 974 Feb 47

It has recently been shown that tumor-associated antigens (TAAs) can evoke tumor-specific T-cell-defined immune responses in cancer patients, thereby offering the possibility of treating patients with such antigens. To develop T-cell-based immunotherapeutic approaches for renal cell carcinoma (RCC), we studied the mRNA expression profile of the TAAs RAGE-1, tyrosinase, MAGE-1, MAGE-2, NY-ESO-1, Melan-A/MART-1, glycoprotein (gp) 75, gp100, beta-catenin, PRAME, and MUM-1 in 14 human RCC cell lines and in tissue specimens of 37 primary RCCs, 2 related metastases, and 33 specimens of normal renal epithelium. Reverse transcription-PCR was performed with TAA-reactive primers, and the specificity of the PCR products was confirmed by Southern blot and/or direct sequencing. PRAME (10 of 14 cell lines), RAGE-1 (7 of 14 cell lines), and gp75 (4 of 14 cell lines) antigens were expressed in a high percentage of RCC cell lines, although the level of TAA expression varied among the different RCC cell lines. However, low levels of TAA expression in RCC cells are sufficient for recognition by TAA-specific CTLs. Transcription of tyrosinase, Melan-A/MART-1, MAGE-1, MAGE-2, NY-ESO-1, gp100, beta-catenin, and MUM-1 was not detected in any RCC cell line. Approximately 50% of surgically removed neoplasias expressed at least one TAA. RAGE-1 mRNA expression was found in 8 of 39 (21%) RCC samples, PRAME mRNA expression was found in 15 of 39 (40%) RCC samples, and gp75 mRNA expression was found in 4 of 39 (11%) RCC samples, but the expression levels of these TAAs were heterogeneous in the different RCC lesions. One RCC specimen expressed MAGE-2, whereas transcription was not detected in any RCC specimen for MAGE-1, NY-ESO-1, tyrosinase, Melan-A/MART-1, gp100, beta-catenin, and MUM-1. The normal kidney epithelium samples were negative for any TAA tested. Thus, RAGE-1, PRAME, and gp75 expression is found with a different frequency in surgically removed lesions and in RCC cell lines, suggesting that a subgroup of RCC patients could be selected for immunotherapeutic strategies that may benefit from immunization against the RAGE-1, gp75, and/or PRAME antigens. However, additional targets for T-cell-based immunotherapy of RCC have yet to be identified.
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PMID:Heterogeneous expression of the tumor-associated antigens RAGE-1, PRAME, and glycoprotein 75 in human renal cell carcinoma: candidates for T-cell-based immunotherapies? 975 17

In the treatment of cutaneous melanoma, provisional therapeutic strategies have been designed to combat tumour load using T cells that are sensitized with peptides derived from melanoma autoantigens, such as glycoprotein 100 (gp100), melanoma antigen recognized by T cells 1 (MART-1 or MelanA), tyrosinase and tyrosinase-related protein 1 (TRP-1). We recently found that gp100, MART-1 and tyrosinase are heterogeneously expressed in human cutaneous melanoma (De Vries et al (1997) Cancer Res 57: 3223-3229). Here, we extended our investigations on expression of these immunotherapy candidate proteins to uveal melanoma lesions. Cryostat sections from 11 spindle-type, 21 mixed and epithelioid tumours and four metastasis lesions were stained with antibodies specifically recognizing gp100, MART-1, tyrosinase and TRP-1. In addition, we used the DOPA reaction to detect tyrosinase enzyme activity as a confirmation of the tyrosinase immunohistochemical results. High expression of gp100, MART-1 and tyrosinase was found in the uveal melanoma lesions: 80% of the lesions displayed 75-100% positive tumour cells. TRP-1 positivity was slightly less: approximately 65% of the lesions stained in the 75-100% positive tumour cell category. All uveal melanoma lesions were positive for the four markers studied, this being in contrast to cutaneous melanoma where 17% of the advanced primary lesions and metastases were negative. The presence of these antigens was a little lower in metastases. We conclude that uveal melanomas and their metastases express melanocyte-lineage immunotherapy candidate proteins very abundantly. Uveal melanomas differ in this respect from cutaneous melanoma, in which the expression of these immunotherapy antigens was much more heterogeneous. This makes uveal melanoma a suitable candidate tumour for immunotherapeutic approaches.
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PMID:High expression of immunotherapy candidate proteins gp100, MART-1, tyrosinase and TRP-1 in uveal melanoma. 982 Jan 72

The pigment epithelium of the retina (RPE) is derived from the optic cup and is essential for function and development of the eye. We produced a transgenic mouse line that expresses simian virus (SV40) transforming sequences under control of the 1.4 kb tyrosinase-related protein 1 (TRP-1) promoter, targeting expression of T antigen (Tag) to the RPE. In transgenic embryos, RPE cells proliferated in the anterior part of the eye and near the optic nerve. This resulted in formation of tumors, which were pigmented and of epithelial origin. In 3 months-old mice, pigmented cells were detected in spleen and inguinal lymph nodes. In spleen, tyrosinase, TRP-1 and SV40 Tag were expressed and tyrosinase was enzymatically active. Pigmented regions were positive for an epithelial marker, cytokeratin. Cell lines were established from tumor and metastases and kept in culture for more than 2 months. These were pigmented, and maintained expression of tyrosinase, TRP-1, cytokeratin and SV40 Tag. This demonstrates that RPE tumor cells metastasize to lymph node and spleen. In conclusion, the metastasis from TRP-1/Tag RPE tumors towards spleen and lymph nodes serves as potential tool to investigate biology and metastasis of tumors derived from the pigment epithelium.
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PMID:Tumors of the retinal pigment epithelium metastasize to inguinal lymph nodes and spleen in tyrosinase-related protein 1/SV40 T antigen transgenic mice. 984 Sep 23

There is ample evidence for spontaneous antimelanoma immune reactivity mediated by melanocyte-differentiation-antigens (MDAs). Our aim was to determine whether MDA immunoreactivity is associated with increased tumour-infiltrating lymphocytes (TIL) and macrophages (TIM). A retrospective study was conducted in 30 medium and high grade primary cutaneous melanomas (PCM) as identified by CART-analysis. All of the cases had developed clinical evidence for metastasis within 3 years following surgical excision of the PCM. We used immunohistochemistry and computerized image analysis to quantify MDAs positive cells (Melan A/MART-1, gp100/Pmel 17/HMB45, tyrosinase), CD45R0-positive TIL and LI-protein-positive TIM. A stochastic relationship was present between the MDA immuno-reactivities and the densities in TIL and TIM. An inverse relationship was yielded between TIL and TIM. No specific pattern of PCM immunoreactivity for MDAs, TIL and TIM was found to predict metastases.
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PMID:Patterns of the immunohistochemical expression of melanoma-associated antigens and density of CD45R0+ activated T lymphocytes and L1-protein positive macrophages in primary cutaneous melanomas. 985 Jul 42

Determination of blood tyrosinase mRNA by RT-PCR and markers of tyrosinase activity (L-DOPA/L-tyrosine ratio) by HPLC have been proposed as biological tools for the detection of metastases in melanoma patients. We prospectively evaluated their significance and clinical value in a group of 30 stage III (n = 10) and IV (n = 20) melanoma patients and one with melanosis of Dubreuilh. L-DOPA/L-tyrosine ratio was elevated in 30% of stage III, 41% of stage IV patients (range: 7.5-261.0 x 10(5)) and in melanosis of Dubreuilh (184.8) (reference values: 6-16 X 10(5)). One stage III and four stage IV melanoma patients were positive for tyrosinase mRNA. In stage IV patients, tyrosinase mRNA positivity was associated with disease progression (P<0.01). The presence of tyrosinase mRNA in blood is more related to clinical status than level of melanin precursors, which probably reflects tumor burden.
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PMID:Simultaneous analysis of tyrosinase mRNA and markers of tyrosinase activity in the blood of patients with metastatic melanoma. 1034 Apr 38

Physical examination and ultrasound B-scan screening are important follow-up procedures in melanoma patients with regional disease. However, they do not allow definite diagnosis of suspicious lesions. Fine-needle aspiration cytology (FNAC) enhances the diagnostic accuracy in such patients but, unfortunately, reaches its technical limits, particularly when very small or necrotic lesions are examined. We therefore tested whether tyrosinase reverse transcription polymerase chain reaction (RT-PCR) of fine-needle aspirates (FNA-PCR) could help to increase diagnostic sensitivity. With clinical follow-up in 69 melanoma patients 81 regional lymph nodes were detected by ultrasound B-scan examination, nine of whom appeared to be palpable. Technically, FNAC was successful in all 81 lymph nodes, while FNA-PCR failed to obtain RNA at detectable levels in two lymph nodes of two patients. Of 79 lesions which have been completely evaluated by B-scan, FNAC and FNA-PCR, 44 proved to be melanoma metastases by histopathology, while the remaining 35 lesions were finally classified as non-specific lymph nodes. Of the 44 melanoma metastases 80% (n = 35) have been detected by B-scan, 90% (n = 39) by FNAC and 100% (n = 44) by FNA-PCR (P < 0.05 vs FNAC, P < 0.005 vs B-scan). In the subclass of lesions with diameters below 10 mm the sensitivities were 72% (n = 13), 78% (n = 14) and 100% (n = 18) respectively. In 35 regional lymph nodes classified as benign lesions, FNAC was always negative while FNA-PCR produced one positive result. Neither of these methods did produce false positive results in 15 control lymph nodes of non-melanoma patients. We conclude, that FNA-PCR might have superior sensitivity as compared to FNAC or ultrasound B-scan, particularly in melanoma lesions with diameters below 10 mm.
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PMID:Detection of regional melanoma metastases by ultrasound B-scan, cytology or tyrosinase RT-PCR of fine-needle aspirates. 1040 17


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