title: Antitumor effect of free rhodium (II) citrate and rhodium (II) citrate-loaded maghemite nanoparticles on mice bearing breast cancer: a systemic toxicity assay.
abstract: Breast cancer is one of the most prevalent cancer types among women. The use of magnetic fluids for specific delivery of drugs represents an attractive platform for chemotherapy. In our previous studies, it was demonstrated that maghemite nanoparticles coated with rhodium (II) citrate (Magh-Rh2Cit) induced in vitro cytotoxicity and in vivo antitumor activity, followed by intratumoral administration in breast carcinoma cells. In this study, our aim was to follow intravenous treatment to evaluate the systemic antitumor activity and toxicity induced by these formulations in Balb/c mice bearing orthotopic 4T1 breast carcinoma. Female Balb/c mice were evaluated with regard to toxicity of intravenous treatments through analyses of hemogram, serum levels of alanine aminotransferase, iron, and creatinine and liver, kidney, and lung histology. The antitumor activity of rhodium (II) citrate (Rh2Cit), Magh-Rh2Cit, and maghemite nanoparticles coated with citrate (Magh-Cit), used as control, was evaluated by tumor volume reduction, histology, and morphometric analysis. Magh-Rh2Cit and Magh-Cit promoted a significant decrease in tumor area, and no experimental groups presented hematotoxic effects or increased levels of serum ALT and creatinine. This observation was corroborated by the histopathological examination of the liver and kidney of mice. Furthermore, the presence of nanoparticles was verified in lung tissue with no morphological changes, supporting the idea that our nanoformulations did not induce toxicity effects. No studies about the systemic action of rhodium (II) citrate-loaded maghemite nanoparticles have been carried out, making this report a suitable starting point for exploring the therapeutic potential of these compounds in treating breast cancer.
authors.affiliation: Institute of Biological Sciences, Department of Cell Biology, University of Brasília (UnB), Brasilia, 70919-970, Brazil.
authors.forename: Raphael Cândido Apolinário
authors.initials: RC
authors.lastname: Peixoto
authors.forename: Ana Luisa
authors.initials: AL
authors.lastname: Miranda-Vilela
authors.forename: José
authors.initials: J
authors.lastname: de Souza Filho
authors.forename: Marcella Lemos' Brettas
authors.initials: ML
authors.lastname: Carneiro
authors.forename: Ricardo G S
authors.initials: RG
authors.lastname: Oliveira
authors.forename: Matheus Oliveira
authors.initials: MO
authors.lastname: da Silva
authors.forename: Aparecido R
authors.initials: AR
authors.lastname: de Souza
authors.forename: Sônia Nair
authors.initials: SN
authors.lastname: Báo
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D005260:Female; D005290:Ferric Compounds / Q000494:pharmacology* / Q000633:toxicity; D022781:Hepatocytes / Q000473:pathology; D007668:Kidney / Q000503:physiopathology; D008321:Mammary Glands, Animal / Q000473:pathology; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D053758:Nanoparticles; D012238:Rhodium / Q000494:pharmacology* / Q000633:toxicity; D015996:Survival Rate
chemical_list: D000970:Antineoplastic Agents; D005290:Ferric Compounds; C000499:ferric oxide; D012238:Rhodium; D000410:Alanine Transaminase