title: Isolation and growth of smooth muscle-like cells derived from tuberous sclerosis complex-2 human renal angiomyolipoma: epidermal growth factor is the required growth factor.
abstract: Tuberous sclerosis complex (TSC) is a tumor suppressor gene disorder characterized by mutations in the TSC1 or TSC2 genes. These mutations lead to the development of benign tumors involving smooth muscle cells, causing life-threatening lymphangioleiomyomatosis. We isolated and characterized two types of cells bearing a mutation in TSC2 exon 18 from a renal angiomyolipoma of a TSC patient: one population of alpha-actin-positive smooth muscle-like cells with loss of heterozygosity for the TSC2 gene (A(+) cells) and another of nonloss of heterozygosity keratin 8/18-positive epithelial-like cells (R(+) cells). Unlike control aortic vascular smooth muscle cells, A(+) cells required epidermal growth factor (EGF) to grow and substituting EGF with insulin-like growth factor (IGF)-1 failed to increase the cell number; however, omission of EGF did not cause cell loss. The A(+) cells constantly released IGF-1 into the culture medium and constitutively showed a high degree of S6K phosphorylation even when grown in serum-free medium. Exposure to antibodies against EGF and IGF-1 receptors caused a rapid loss of A(+) cells: 50% by 5 days and 100% by 12 days. Signal transduction mediated by EGF and IGF-I receptors is therefore involved in A(+) cell survival. These results may offer a novel therapeutic perspective for the treatment of TSC complications and lymphangioleiomyomatosis.
authors.affiliation: Laboratory of Pharmacology, Faculty of Medicine, University of Milan, Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Lesma
authors.forename: Vera
authors.initials: V
authors.lastname: Grande
authors.forename: Stephana
authors.initials: S
authors.lastname: Carelli
authors.forename: Diego
authors.initials: D
authors.lastname: Brancaccio
authors.forename: Maria Paola
authors.initials: MP
authors.lastname: Canevini
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Alfano
authors.forename: Guido
authors.initials: G
authors.lastname: Coggi
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Di Giulio
authors.forename: Alfredo
authors.initials: A
authors.lastname: Gorio
mesh_terms: D000199:Actins / Q000378:metabolism; D000328:Adult; D018207:Angiomyolipoma / Q000235:genetics / Q000473:pathology*; D001011:Aorta / Q000166:cytology; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002470:Cell Survival / Q000187:drug effects; D004252:DNA Mutational Analysis; D004815:Epidermal Growth Factor / Q000494:pharmacology / Q000502:physiology*; D005091:Exons; D005260:Female; D016650:Fluorescein-5-isothiocyanate; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D016147:Genes, Tumor Suppressor; D005819:Genetic Markers; D006801:Humans; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000378:metabolism / Q000494:pharmacology; D007633:Keratins / Q000378:metabolism; D019656:Loss of Heterozygosity; D018895:Microsatellite Repeats; D009130:Muscle, Smooth / Q000737:chemistry / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000737:chemistry / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D009154:Mutation; D010766:Phosphorylation; D012235:Rhodamines; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D014402:Tuberous Sclerosis / Q000235:genetics / Q000473:pathology*; D000077004:Tuberous Sclerosis Complex 1 Protein; D000077005:Tuberous Sclerosis Complex 2 Protein; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000199:Actins; D005456:Fluorescent Dyes; D005819:Genetic Markers; D012235:Rhodamines; C000624650:TSC1 protein, human; C000624653:TSC2 protein, human; D000077004:Tuberous Sclerosis Complex 1 Protein; D000077005:Tuberous Sclerosis Complex 2 Protein; D025521:Tumor Suppressor Proteins; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D007633:Keratins; D038762:Ribosomal Protein S6 Kinases, 70-kDa; C448959:ribosomal protein S6 kinase, 70kD, polypeptide 2; D016650:Fluorescein-5-isothiocyanate