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 melanomas of the oral and sinonasal mucosa are rare tumors. Amelanotic variants can, on occasion, be difficult to recognize by routine light microscopy. Immunohistochemical studies may be needed for a final diagnosis. A number of new monoclonal antibodies to melanocytic differentiation antigens have been studied recently on primary cutaneous and metastatic melanoma. However, little is known about these antibodies for the diagnosis of mucosal melanomas. In this study the authors analyzed 79 oral and sinonasal mucosal melanomas of 65 patients. A total of 35 tumors originated from the oral mucosa (21 primary tumors, eight local recurrences, and six metastases) and 44 melanomas were from the sinonasal tract (27 primary tumors, nine local recurrences, and eight metastases). Immunohistochemical studies were performed on paraffin-embedded tissues, using the following antibodies: anti-S-100 protein, T311 (anti-tyrosinase), A103 (anti-Mart-1/Melan-A), D5 (antimicrophthalmia-associated transcription factor), and HMB-45 (anti-gp100). Of 35 oral mucosal tumors, 34 (97%) were positive with anti-S-100 protein, 33 (94%) with T311, 30 (85%) with A103, 26 (74%) with D5, and 25 (71%) with HMB-45. All five desmoplastic melanomas of the oral mucosa were positive for S-100 protein, four for tyrosinase, and one each for HMB-45 and A103. No desmoplastic melanoma was positive with D5. All 44 sinonasal melanomas were positive for tyrosinase and Mart-1/Melan-A (100%). Forty-three (98%) were positive with HMB-45, 42 (95%) with anti-S-100 protein, and 40 (91%) with D5. These results reveal that T311 is the most sensitive marker for sinonasal melanomas and closely approaches the sensitivity of anti-S-100 protein for oral mucosal melanomas. For desmoplastic mucosal tumors, anti-S-100 protein remains the most sensitive marker.
 ...
PMID:Expression of melanocytic differentiation markers in malignant melanomas of the oral and sinonasal mucosa. 1139 56

The melanoma patient's immune response to tumor has been extensively studied. Yet, the frequently observed coexistence of tumor-associated Ag (TAA)-specific T cells with their target cells in vivo remains unexplained. Loss of TAA expression might contribute to this paradox. We studied TAA expression in metastases by obtaining fine-needle aspirations from 52 tumor lesions in 30 patients with melanoma before and soon after immunotherapy. Limitations due to low amounts of starting material were overcome with a high fidelity antisense RNA amplification method. TAA expression was measured by quantitative real-time PCR of anti-sense RNA. Decrease in gp100/Pmel-17 TAA preceded tumor disappearance in several instances and could be best explained by immune selection because most patients had received gp100/Pmel-17-specific vaccination. Conversely, immune selection was absent in nonregressing lesions. These observations suggest that vaccination, when successful, triggers a broad inflammatory reaction that can lead to tumor destruction despite immune selection. Additionally, lack of clinical response might be attributed to lack of this initiating event rather than immune escape. This study provides an insight into the natural history of tumors and defines a strategy for the characterization of gene expression in tumors during therapy.
 ...
PMID:Short-term kinetics of tumor antigen expression in response to vaccination. 1146 7

Immunization to multiple defined tumor antigens for specific immune therapy of human cancer has thus far proven difficult. Eighteen HLA A*0201(+) patients with metastatic melanoma received injections s.c. of CD34(+)progenitor-derived autologous dendritic cells (DCs), which included Langerhans cells. DCs were pulsed with peptides derived from four melanoma antigens [(MelAgs) MelanA/MART-1, tyrosinase, MAGE-3, and gp100], as well as influenza matrix peptide (Flu-MP) and keyhole limpet hemocyanin (KLH) as control antigens. Overall immunological effects were assessed by comparing response profiles using marginal likelihood scores. DC injections were well tolerated except for progressive vitiligo in two patients. DCs induced an immune response to control antigens (KLH, Flu-MP) in 16 of 18 patients. An enhanced immune response to one or more MelAgs was seen in these same 16 patients, including 10 patients who responded to >2 MelAgs. The two patients failing to respond to both control and tumor antigens experienced rapid tumor progression. Of 17 patients with evaluable disease, 6 of 7 patients with immunity to two or less MelAgs had progressive disease 10 weeks after study entry, in contrast to tumor progression in only 1 of 10 patients with immunity to >2 MelAgs. Regression of >1 tumor metastases were observed in seven of these patients. The overall immunity to MelAgs after DC vaccination is associated with clinical outcome (P = 0.015).
 ...
PMID:Immune and clinical responses in patients with metastatic melanoma to CD34(+) progenitor-derived dendritic cell vaccine. 1152 40

We characterized the HLA class I alterations in five metastases obtained from two patients with melanoma immunized with Melan A/MART-1, tyrosinase and gp100 tumor peptides. All three metastases analyzed in the first patient (NW145) showed a similar HLA class I alteration with a dual population of melanoma cells. One population was HLA class I antigen positive and the other had loss of heterozygosity (LOH) in the short arm of chromosome 6 leading to an HLA haplotype loss (A02011, B4007, Cw1). The absence of HLA-A2 antigen may explain why this patient did not develop HLA-A2 restricted, Melan A/MART-1 specificity immunization, since this HLA molecule is the restriction element for the tumor peptides used. However, this HLA-deficient population was not selected after peptide immunotherapy. The primary tumor in this patient presented LOH in region 6q, but only in the vertical growth phase of the lesion, whereas LOH at 6p was observed only in DNA from metastatic material. The second patient (NW16) also presented two metastatic lesions with an identical HLA molecular defect, i.e. HLA B locus downregulation (HLA B51011: serological B51; B1503: serological B70). One lesion expressed the tumor antigen (Melan A/ MART-1), but the other did not. Interestingly, the antigen-positive metastasis regressed after peptide immunotherapy, whereas the other progressed rapidly. These findings provide the first indication that multiple metastases generated in the same host can have identically altered HLA class I phenotypes.
 ...
PMID:Analysis of HLA class I expression in different metastases from two melanoma patients undergoing peptide immunotherapy. 1155 81

A melanoma vaccine composed of HLA-A2-restricted peptide YLEPGPVTA (gp100(280)), with or without a modified T-helper epitope from tetanus toxoid AQYIKANSKFIGITEL, has been evaluated in a Phase I trial to assess safety and immunological response. The vaccines were administered s.c. in either of two adjuvants, Montanide ISA-51 or QS-21, to 22 patients with high-risk resected melanoma (stage IIB-IV). Local and systemic toxicities were mild and transient. We detected CTL responses to the gp100(280) peptide in peripheral blood in 14% of patients. Helper T-cell responses to the tetanus helper peptide were detected in 79% of patients and had a Th1 cytokine profile. One patient with a CTL response to gp100 had a recurrence in a lymph node 2 years later; her nodes contained CD8+ cells reactive to gp100(280) (0.24%), which proliferated in response to peptide. The overall survival of patients is 75% (95% confidence interval, 57-94%) at 4.7 years follow-up, which compares favorably with expected survival. Four of 14 patients who completed at least six vaccines subsequently developed metastases, all of which were solitary and surgically resectable. They remain alive and clinically free of disease at last follow-up. Data from this trial demonstrate immunogenicity of the gp100(280) peptide and suggest that immune responses may persist long-term in some patients. The frequency and magnitude of the CTL response may be improved with more aggressive vaccination regimens. Although this Phase I study was not intended to evaluate clinical benefit, the excellent survival of patients on this protocol suggests the possibility of a benefit that should be assessed in future studies.
 ...
PMID:Phase I trial of a melanoma vaccine with gp100(280-288) peptide and tetanus helper peptide in adjuvant: immunologic and clinical outcomes. 1159 89

In this study, we investigated whether maturation of monocyte-derived myeloid dendritic cells (DCs) is differentially affected by the uptake of dying human melanoma cells in distinct phases of apoptosis. Maturation of monocyte-derived DCs, as documented by phenotype analysis and T-cell immunostimulatory activity, was inhibited by phagocytosis of dying melanoma cells containing a large fraction of cells in early apoptosis (Annexin-V+ and propidium iodide-) but promoted by the same tumors when in late apoptosis/secondary necrosis (Annexin-V+ and propidium iodide+) or when dying by primary necrosis. These opposite effects on DC maturation were observed after the uptake of early or late apoptotic cells from most vertical growth phase primary tumors and all metastases but not after the uptake of dying cells from a radial growth phase primary tumor or normal adult melanocytes. Inhibition of DC maturation by early apoptotic melanoma cells correlated with expression of interleukin-10 in neoplastic cells and was prevented by preincubating the tumor cells with a neutralizing antibody to interleukin-10 before tumor uptake by DCs. Cross-presentation of the melanoma-associated antigen gp100(209-217) to peptide-specific CTLs by HLA-A*0201+ DCs was achieved 48-72 h after phagocytosis of HLA-A*0201- melanoma cells in apoptosis, or primary necrosis, but only when tumor necrosis factor-alpha was added to DCs 4 h after the initiation of tumor phagocytosis. These results suggest that phases of apoptosis and neoplastic transformation affect maturation of myeloid DCs that take up dying cells of the melanocyte lineage. However, neoplastic cells in late apoptosis, or even in primary necrosis, induce only a partial DC differentiation not sufficient to achieve cross-presentation of tumor antigens to CTLs unless further DC maturation is promoted by additional signals. These results suggest a novel mechanism of tumor escape that may prevent the development of antitumor immunity through the maturation block induced in DCs by neoplastic cells in the early phase of apoptosis.
 ...
PMID:Phases of apoptosis of melanoma cells, but not of normal melanocytes, differently affect maturation of myeloid dendritic cells. 1171 53

Assessment of antigen expression by solid tumors has relied predominantly on immunohistochemistry, flow cytometry, and more recently quantitative real-time polymerase chain reaction. However, all these techniques present intrinsic limits. The laser scanning cytometer, by combining the properties of light and fluorescence microscopy with those of laser cytometry, can quantitatively and objectively analyze hypocellular samples such as fine-needle aspirates on an individual cell basis. To validate the fidelity of laser scanning cytometry for quantitative immunophenotyping of fine-needle aspirates, the authors measured the expression of the melanoma-associated antigens MART-1 and gp100 as well as HLA-A2, a HLA class 1 restriction element associated with their recognition by melanoma-specific T cells. Expression of melanoma antigens and HLA was measured by laser scanning cytometry and immunohistochemistry in fine-needle aspirates from melanoma metastases. In addition, transcription levels of both melanoma antigens were recorded by quantitative real-time polymerase chain reaction. A quantity of less than 1,000 cells per sample (average 682 cells) was sufficient for the analysis. Laser scanning cytometry estimates correlated with those of immunohistochemistry and quantitative real-time polymerase chain reaction for MART-1 and gp100. A good correlation in HLA-A2 detection by laser scanning cytometry and immunohistochemistry was also observed. Moreover, the laser scanning cytometer could discriminate subsets of cells from the same lesion with heterogeneous melanoma antigen expression, leading to the observation that cells with a DNA index greater than 2.5 expressed significantly less gp100. Thus, laser scanning cytometry yields detailed information on protein expression in individual cells and represents a new tool for dissecting the immune response in the tumor microenvironment.
 ...
PMID:Laser scanning cytometry evaluation of MART-1, gp100, and HLA-A2 expression in melanoma metastases. 1175 68

In malignant melanoma, tumor-infiltrating lymphocytes are frequently reactive with melanosomal antigens. Achieving complete remissions by peptide therapy is frequently hampered by metastases evading immune recognition. The tumor microenvironment seems to favor reduced expression of target antigens by melanoma cells. Among candidate factors, interferon-gamma (IFN-gamma) (10(2) to 10(3) U/ml) suppressed expression of antigens MART-1, TRP-1, and gp100 by M14 melanoma cells as shown by immunohistology and fluorescence-activated cell sorting analysis, reducing MART-1 expression by >65%. Northern blot analysis revealed that reduced expression was regulated at the transcriptional level, demonstrating a 79% reduction in MART-1 transcript abundance after 32 hours of IFN-gamma treatment. To evaluate consequences of IFN-gamma exposure for immune recognition, MART-1-responsive T cells were reacted with pretreated HLA-matched melanoma cells. Cytotoxicity was reduced up to 78% by IFN-gamma pretreatment, and was restored by addition of MART-1 peptide AAGIGILTV for 2 hours. Examination of melanoma lesions by quantitative reverse transcriptase-polymerase chain reaction revealed up to 188-fold more abundant IFN-gamma transcripts when compared to control skin. Laser capture microdissection and immunohistology localized most IFN-gamma-producing T cells to the tumor stroma. Reduced MART-1 expression was frequently observed in adjacent tumor cells. Consequently, IFN-gamma may enhance inflammatory responses yet hamper effective recognition of melanoma cells.
 ...
PMID:Interferon-gamma reduces melanosomal antigen expression and recognition of melanoma cells by cytotoxic T cells. 1183 72

Nodal nevi represent a potential diagnostic pitfall in the analysis of lymph nodes. They may be confused with metastatic melanoma or carcinoma. Although several morphologic guidelines exist for the recognition of nodal nevi, on occasion immunohistochemical studies may be helpful for diagnosis, especially when melanocytes extend into the lymph node parenchyma. To learn more about the immunohistochemical profile of nodal nevi we examined 15 nodal nevi for the expression of S-100 protein, gp100 (HMB-45), Melan-A/MART-1 (A103), and tyrosinase (T311), and we studied the expression of Ki-67 (MIB-1) in nodal nevi and 40 melanoma metastases (35 lymph node and five cutaneous metastases). All nodal nevi were homogeneously immunoreactive for S-100 protein, tyrosinase, and Melan-A/MART-1. Two nodal nevi were focally positive for gp100. Fourteen of 15 nodal nevi were completely negative for Ki-67. One large cellular nodal nevus showed nuclear labeling in <0.2% of melanocytes. All metastases showed MIB-1 labeling. However, the percentage of labeled tumor cells varied widely, ranging from 2% to 80%. These results demonstrate that MIB-1 and HMB-45 are helpful reagents for the distinction of nodal nevi from melanoma. Immunohistochemistry for S-100 protein, Melan-A/MART-1, or tyrosinase facilitates the recognition of melanocytes but does not distinguish between nodal nevus and metastatic melanoma.
 ...
PMID:Expression of melanocyte differentiation antigens and ki-67 in nodal nevi and comparison of ki-67 expression with metastatic melanoma. 1236 50

Adoptive T cell therapy, involving the ex vivo selection and expansion of antigen-specific T cell clones, provides a means of augmenting antigen-specific immunity without the in vivo constraints that can accompany vaccine-based strategies. A phase I study was performed to evaluate the safety, in vivo persistence, and efficacy of adoptively transferred CD8+ T cell clones targeting the tumor-associated antigens, MART1MelanA and gp100 for the treatment of patients with metastatic melanoma. Four infusions of autologous T cell clones were administered, the first without IL-2 and subsequent infusions with low-dose IL-2 (at 0.25, 0.50, and 1.0 x 10(6) unitsm(2) twice daily for the second, third, and fourth infusions, respectively). Forty-three infusions of MART1MelanA-specific or gp100-specific CD8+ T cell clones were administered to 10 patients. No serious toxicity was observed. We demonstrate that the adoptively transferred T cell clones persist in vivo in response to low-dose IL-2, preferentially localize to tumor sites and mediate an antigen-specific immune response characterized by the elimination of antigen-positive tumor cells, regression of individual metastases, and minor, mixed or stable responses in 8 of 10 patients with refractory, metastatic disease for up to 21 mo.
 ...
PMID:Adoptive T cell therapy using antigen-specific CD8+ T cell clones for the treatment of patients with metastatic melanoma: in vivo persistence, migration, and antitumor effect of transferred T cells. 1246 Nov 64


<< Previous 1 2 3 4 5 6 Next >>