title: Effect of rosiglitazone on N-nitroso-N-methylurea-induced mammary tumors in rat.
abstract: The objective of this study was to evaluate the in vivo antitumor action of rosiglitazone (Rosi) alone or in combination with tamoxifen (Tam) on experimental mammary tumors induced by N-nitroso-N-methylurea (NMU) in Sprague-Dawley rats. Animals bearing mammary tumors were treated with 0.06 mg/kg/day or 0.12 mg/kg/day of Rosi orally, 1 mg/kg/day of Tam s.c., or with the combined treatment (Rosi+Tam). After 25 days of treatment, the following responses were observed: 45% of tumors were responsive to 0.06 mg/kg/day of Rosi treatment, while 55% of tumors under Tam treatment responded. The results of the combined Rosi+Tam treatment indicated that 75% of tumors were responsive. Similar results were obtained with 0.12 mg/kg/day of Rosi. Apoptosis, necrosis and glandular hypersecretion were observed in Rosi-treated tumors. In all cases, the combined Rosi+Tam treatment potentiated the antitumor effect of Tam alone. No side-effects were observed after treatment at any assayed dose.
authors.affiliation: Radioisotopes Laboratory, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Mariel
authors.initials: M
authors.lastname: Núñez
authors.forename: Gabriela
authors.initials: G
authors.lastname: Martín
authors.forename: Claudia
authors.initials: C
authors.lastname: Cocca
authors.forename: Nora
authors.initials: N
authors.lastname: Mohamad
authors.forename: Alicia
authors.initials: A
authors.lastname: Gutiérrez
authors.forename: Graciela
authors.initials: G
authors.lastname: Cricco
authors.forename: Vanina
authors.initials: V
authors.lastname: Medina
authors.forename: Elena
authors.initials: E
authors.lastname: Rivera
authors.forename: Máximo
authors.initials: M
authors.lastname: Croci
authors.forename: Ernesto
authors.initials: E
authors.lastname: Crescenti
authors.forename: Rosa
authors.initials: R
authors.lastname: Bergoc
mesh_terms: D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D001835:Body Weight / Q000187:drug effects; D048708:Cell Growth Processes / Q000187:drug effects; D004326:Drinking / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D005260:Female; D005951:Glucose Tolerance Test; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008770:Methylnitrosourea; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077154:Rosiglitazone; D013629:Tamoxifen / Q000008:administration & dosage; D045162:Thiazolidinediones / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D007328:Insulin; D045162:Thiazolidinediones; D000077154:Rosiglitazone; D013629:Tamoxifen; D007334:Insulin-Like Growth Factor I; D008770:Methylnitrosourea