Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0278883 (metastatic melanoma)
 6,224 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High molecular weight antigen (HMWA) is a tumor-associated proteoglycan of human malignant melanoma. I-131 labeled Fab fragments of these specific antibodies were used for preliminary feasibility studies for radioimmunodetection and therapy of human subjects who had inoperable metastatic melanoma. Ten patients received tracer doses of 5-13 mCi (185-481 MBq) of I-131 (anti-HMWA) Fab. All patients (8/8) who had melanoma lesions greater than 1 cm by correlative diagnostic methods had one or more lesions that had localization to tumor of the radiolabeled Fab. In all, 17 of 23 (74%) documented metastases were seen. There were no false positives in this series. Two patients who had avid uptake received potentially radiotherapeutic doses of 142 mCi (5,254 MBq) (one patient) and 181 mCi (6,697 MBq) and 193 (7,141 MBq) (total: 374 mCi or 13,838 MBq) (one patient). For both of these patients, whole body imaging studies showed that the localization of the high dose I-131 Fab was predominantly in tumor. The patient who received the larger dose showed a greater than 50% reduction in the size of pelvic and pericaval nodes, with stabilization of disease at the smaller nodal size for a period of three months. On whole body images, the anti-Fab HMWA appears to be more tumor selective than Fab preparations that target the p97 antigen for melanoma, and there is less uptake in liver.
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PMID:Use of I-131 labeled, murine Fab against a high molecular weight antigen of human melanoma: preliminary experience. 398

Mouse monoclonal antibodies (mAb) detecting 13 distinct systems of surface antigens on cultured melanocytes and melanomas were tested for reactivity with panels of (a) normal and malignant cultured cells; (b) normal adult and fetal tissues; and (c) specimens of metastatic melanoma and other tumor types. The objectives of this study were to compare antigen expression in cultured versus noncultured cells, to develop a panel of mAbs that identify subsets of melanomas, and to provide requisite information about antibody specificity in preparation for the use of antibodies in the diagnosis, imaging, and therapy of melanoma. Five of the melanoma surface antigens have been well characterized biochemically [GD3, chondroitin sulfate proteoglycan, HLA Class II antigens, glycoprotein of molecular weight 130,000 (gp130), and glycoprotein Mr 95,000/protein Mr 97,000 (gp95/p97)]. Three antigens have been related to melanocyte differentiation (HLA Class II, M111/M231, and M144), and six provide additional markers for subsets of cultured melanomas. mAb R24 reacts with the disialoganglioside GD3, a predominant ganglioside on cultured melanoma cells and other cells of neuroectodermal origin. A high proportion of melanoma, astrocytoma, and sarcoma tissue specimens were GD3+. In normal tissues, reactivity of mAb R24 was restricted to melanocytes, neuronal and glial cells in the central nervous system, parotid gland, adrenal medullary cells, and rare cells in the connective tissue. mAb B5 detects a chondroitin sulfate proteoglycan that is expressed by most melanoma and astrocytoma cell lines and by cultured melanocytes. Most of the melanoma and astrocytoma specimens were B5+, whereas other tumor types tested were B5-. mAb 13-17, which detects a monomorphic determinant of HLA Class II antigens, reacted with melanomas, and with a variety of other cancers, but not with normal skin melanocytes. There is considerable variability in the expression of GD3 and HLA Class II antigens in individual melanoma specimens; cotyping for these two antigens showed no evidence for coordinate expression. mAb L101 detects gp130 and mAb L235 detects gp95, antigens that are strongly expressed on a broad range of cultured cell types. In contrast to their wide distribution on cultured cells, gp130 expression in tissues was generally restricted to a subset of melanomas and some normal cells, and gp95 was detected on only a small number of melanomas. mAb M111/mAb M231 and mAb M144 define intermediate and late stage differentiation markers of cultured melanocytes and melanomas.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Surface antigens of melanomas and melanocytes defined by mouse monoclonal antibodies: specificity analysis and comparison of antigen expression in cultured cells and tissues. 402 24

The aim of this pilot study was to assess the clinical and immunological effects of human allogeneic liposomal melanoma vaccine alone or combined with Interleukin-2 (IL-2) in patients with metastatic melanoma. Four concurrent treatment arms were included: vaccine alone (A); vaccine combined with systemic IL-2 (B); vaccine combined with low-dose liposomal regional IL-2 (C); and low-dose regional IL-2 as in group C but without vaccine (D). Vaccine was prepared from semisynthetic phospholipids (dimyristol phosphatidylcholine and dimyristol phosphatidylglycerol) and membranes of six human melanoma cell lines. The latter were chosen as expressing MHC class I and II antigens and a "mosaic" of melanoma-associated antigens (MAAs) as detected by MoAbs R24, p97, CF21 and TA99. Nine of the 24 patients had objective clinical responses: of the ten patients treated with liposomal vaccine and low dose regional IL-2 (arm C), three had complete responses (CR) and three had partial responses (PR); of the five patients treated with liposomal, low-dose regional liposomal IL-2 only (arm D), three had PRs. No clinical responses were seen in patients treated by vaccine alone (A) nor in patients treated by vaccine and systemic IL-2 (B). Patients' in vivo and in vitro cellular immune responses were closely monitored. Conversion to positive cutaneous delayed type hypersensitivity (DTH) to membrane vaccine (without liposomes) was induced only in the six clinical responders of arm C. Positive DTH correlated with augmented in vitro proliferative lymphocyte responses stimulated by melanoma cell lines and membrane preparation and with the augmented cytolytic activity against melanoma cell lines.
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PMID:Allogeneic human liposomal melanoma vaccine with or without IL-2 in metastatic melanoma patients: clinical and immunobiological effects. 859 Aug 95

Identifying factors that determine the sensitivity or resistance of cancer cells to cytotoxicity by antibody-drug conjugates is essential in the development of such conjugates for therapy. Here the monoclonal antibody L49 is used to target melanotransferrin, a glycosylphosphatidylinositol-anchored glycoprotein first identified as p97, a cell-surface marker in melanomas. L49 was conjugated via a proteolytically cleavable valine-citrulline linker to the antimitotic drug, monomethylauristatin F (vcMMAF). Effective drug release from L49-vcMMAF likely requires cellular proteases most commonly located in endosomes and lysosomes. Melanoma cell lines with the highest surface p97 expression (80,000-280,000 sites per cell) were sensitive to L49-vcMMAF whereas most other cancer cell lines with lower p97 expression were resistant, as were normal cells with low copy numbers (< or = 20,000 sites per cell). Cell line sensitivity to L49-vcMMAF was found by immunofluorescence microscopy to correlate with intracellular fate of the conjugate. Specifically, L49-vcMMAF colocalized with the lysosomal marker CD107a within sensitive cell lines such as SK-MEL-5 and A2058. In contrast, in resistant cells expressing lower p97 levels (H3677; 72,000 sites per cell), L49-vcMMAF colocalized with caveolin-1, a protein prominent in caveolae, but not with CD107a. Thus, for antibody-drug conjugates targeting p97, antigen level and trafficking to the lysosomes are important factors for achieving robust in vitro cytotoxicity against cancer cells. Immunohistochemical analysis with L49 revealed that 62% of metastatic melanoma tumors had strong staining for p97. Overexpression of p97 in melanoma as compared with normal tissue, in conjunction with the greater sensitivity of tumor cells to L49-vcMMAF, supports further evaluation of antibody-drug conjugates for targeting p97-overexpressing tumors.
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PMID:Potent cytotoxicity of an auristatin-containing antibody-drug conjugate targeting melanoma cells expressing melanotransferrin/p97. 1681 6

Melanoma has markedly increased worldwide during the past several decades in the Caucasian population and is responsible for 80% of skin cancer deaths. Considering that metastatic melanoma is almost completely resistant to most current therapies and is linked with a poor patient prognosis, it is crucial to further investigate potential molecular targets. Major cell-autonomous drivers in the pathogenesis of this disease include the classical MAPK (i.e., RAS-RAF-MEK-ERK), WNT, and PI3K signaling pathways. These pathways play a major role in defining the progression of melanoma, and some have been the subject of recent pharmacological strategies to treat this belligerent disease. This review describes the latest advances in the understanding of melanoma progression and the major molecular pathways involved. In addition, we discuss the roles of emerging molecular players that are involved in melanoma pathogenesis, including the functional role of the melanoma tumor antigen, p97/MFI2 (melanotransferrin).
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PMID:Roads to melanoma: Key pathways and emerging players in melanoma progression and oncogenic signaling. 2684 74