title: alpha-Melanotropin immunoreactivity in human melanoma exudate is related to necrosis.
abstract: We have previously reported high immunoreactive alpha-MSH (IR-alpha-MSH) concentrations in melanoma patients' plasma, as well as significant amounts in melanoma metastases and cells grown in culture. Necrosis within the melanoma tumour leads to a massive proteolysis of intracellular proteins and release of cell content: this might significantly contribute to the elevated IR-alpha-MSH plasma levels measured in melanoma patients. To test this hypothesis, we studied the necrosis-related release of MSH from human melanoma cells, using a specific radioimmunoassay. The studies of fine-needle biopsies indicated that most of the human melanoma tumour exudates tested contained very high MSH concentrations (> 500 pg/ml; 14/15), while plasma levels were generally normal (< or = 25 pg/ml; 10/15). The level in an exudate from a non-melanoma tumour type was < 40 pg/ml. In vitro studies showed that release of the IR-alpha-MSH was time- and temperature-dependent, and related to cell death.
authors.affiliation: Laboratory of Oncology and Experimental Surgery, Université Libre de Bruxelles, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Loir
authors.forename: F
authors.initials: F
authors.lastname: Sales
authors.forename: R
authors.initials: R
authors.lastname: Deraemaecker
authors.forename: R
authors.initials: R
authors.lastname: Morandini
authors.forename: J C
authors.initials: JC
authors.lastname: Garcia-Borron
authors.forename: G
authors.initials: G
authors.lastname: Ghanem
mesh_terms: D006801:Humans; D007150:Immunohistochemistry; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism*; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D009336:Necrosis; D011863:Radioimmunoassay; D014407:Tumor Cells, Cultured
chemical_list: D009074:Melanocyte-Stimulating Hormones