Proto-oncogene expression in dermal naevi and melanomas.
Overexpression of proto-oncogenes (c-onc) may be involved in the initiation and progression of human neoplasia. We investigated the mRNA expression of the proto-oncogenes c-myc, c-fos, c-neu (erb B-2) and Ha-ras in 12 cutaneous melanocytic lesions (four dermal naevi, seven melanomas; one cutaneous metastatis of melanoma) and in normal skin (five cases) by Northern blot analysis; mRNA expression levels were quantified by densitometry of the specific bands. The expression of c-myc mRNA was higher in naevi than in melanomas, whereas c-fos mRNA expression was significantly higher in melanomas than in naevi. No significant differences were detected in the c-neu and Ha-ras mRNA levels in naevi and melanomas. The expression of c-neu mRNA was higher in normal skin than in the melanocytic lesions examined. Our results suggest that enhanced c-myc and c-fos expression may play an important role in the growth of melanocytic naevi and melanomas. The overexpression of c-fos may be involved in the progression of a particular subset of melanoma. Activation of Ha-ras and the c-neu gene, as determined by mRNA overexpression, does not seem to play a significant role in the progression of cutaneous pigmented lesions. Expression of c-neu may have an important function in the proliferation and/or differentiation of normal cells of the epidermis.
Department of Dermatology, University of L'Aquila, Italy.
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Peris
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Cerroni
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Chimenti
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Soyer
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Kerl
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Höfler
D016762:Genes, fos; D016259:Genes, myc; D011905:Genes, ras; D006801:Humans; D008545:Melanoma / Q000235:genetics*; D009506:Nevus / Q000235:genetics*; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000235:genetics; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000032:analysis*; D018719:Erb-b2 Receptor Tyrosine Kinases; D012878:Skin Neoplasms / Q000235:genetics*
D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; C000715470:MAS1 protein, human