RESUMO
We report on an improved method of synthesis of N-benzylaminoferrocene-based prodrugs and demonstrate its applicability by preparing nine new aminoferrocenes. Their effect on the viability of selected cancer cells having different p53 status was studied. The obtained data are in agreement with the hypothesis that the toxicity of aminoferrocenes is not dependent upon p53 status. Subsequently the toxicity of a selected prodrug (4) was investigated ex vivo using rat precision cut liver slices and in vivo on hybrid male mice BDF1. In both experiments no toxicity was observed: ex vivo, up to 10 µM; in vivo, up to 6 mg/kg. Finally, prodrug 4 was shown to extend the survival of BDF1 mice carrying L1210 leukemia from 13.7 ± 0.6 days to 17.5 ± 0.7 days when injected daily 6 times at a dose of 26 µg/kg starting from the second day after injection of L1210 cells.
Assuntos
Antineoplásicos/farmacologia , Carbamatos/farmacologia , Carbamatos/toxicidade , Compostos Ferrosos/farmacologia , Compostos Ferrosos/toxicidade , Leucemia/tratamento farmacológico , Pró-Fármacos/farmacologia , Pró-Fármacos/toxicidade , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Carbamatos/síntese química , Carbamatos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Compostos Ferrosos/síntese química , Compostos Ferrosos/química , Células HL-60 , Humanos , Técnicas In Vitro , Injeções Intraperitoneais , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Modelos Moleculares , Estrutura Molecular , Pró-Fármacos/síntese química , Pró-Fármacos/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
We report the Förster resonance energy transfer (FRET)-labeling of liposomal vesicles as an effective approach to study in dynamics the interaction of liposomes with living cells of different types (rat hepatocytes, rat bone marrow, mouse fibroblast-like cells and human breast cancer cells) and cell organelles (hepatocyte nuclei). The in vitro experiments were performed using fluorescent microspectroscopic technique. Two fluorescent dyes (DiO as the energy donor and DiI as an acceptor) were preloaded in lipid bilayers of phosphatidylcholine liposomes that ensures the necessary distance between the dyes for effective FRET. The change in time of the donor and acceptor relative fluorescence intensities was used to visualize and trace the liposome-to-cell interaction. We show that FRET-labeling of liposome vesicles allows one to reveal the differences in efficiency and dynamics of these interactions, which are associated with composition, fluidity, and metabolic activity of cell plasma membranes.
Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Lipossomos , Animais , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Camundongos , RatosRESUMO
The resistance of cancer cells to chemotherapeutic agents is a major clinical problem and an important cause of treatment failure in cancer. Mechanisms that have developed to guard cancer cells against anti-cancer drugs are major barriers to successful anti-cancer therapy. Therefore, the identification of novel mechanisms of cellular resistance holds the promise of leading to better treatments for cancer patients. In the present study, we used human MCF-7 breast adenocarcinoma cell line and its doxorubicin-resistant variant MCF-7/R to determine the role of alterations of DNA methylation of chemoresitance-related genes, such as multidrug resistance 1 (MDR1), glutathione-S-transferase (GSTpi), O(6)-methylguanine DNA methyltransferase (MGMT), and urokinase (Upa), in the development of drug resistance. The promoter regions of MDR1, GSTpi, MGMT, and Upa genes were highly methylated in MCF-7 cell line but not in its MCF-7/R drug resistant variant. The hypomethylated status of MDR1 gene was associated with overexpression of P-glycoprotein. We hypothesize that acquirement of doxorubicin resistance of MCF-7 cells is associated with DNA hypomethylation of the promoter regions of the MDR1, GSTpi, MGMT, and Upa genes.
Assuntos
Adenocarcinoma/patologia , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Metilação de DNA , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes MDR , Glutationa Transferase/genética , Humanos , O(6)-Metilguanina-DNA Metiltransferase/genética , Regiões Promotoras Genéticas , Ativador de Plasminogênio Tipo Uroquinase/genéticaRESUMO
UNLABELLED: The AIM of work was to evaluate the alteration of the total proteolytic activity (TPA) and the levels of alpha(1)-proteinase inhibitor (alpha1PI) and alpha(2)-macroglobuline (alpha2M) in blood plasma of rats bearing Guerin carcinoma upon the development of Doxorubicin (DOX) resistance. MATERIALS AND METHODS: TPA and alpha1PI and alpha2M content in the blood plasma of male Wistar rats bearing DOX-resistant and DOX-sensitive Guerin carcinoma were evaluated by standard biochemical methods. RESULTS: During growth of both DOX-sensitive and DOX-resistant Guerin carcinoma, TPA decrease in blood plasma and the increase of alpha1PI levels were registered; in DOX-resistant group this effect was more pronounced. Alpha2M content in blood plasma of animals from both experimental groups was considerably smaller than that of the control and was the lowest in DOX-resistant group. CONCLUSION: The growth of DOX-resistant Guerin carcinoma is accompanied by imbalance of proteolysis processes in the blood plasma, particularly, alteration of TPA and alpha1PI and alpha2M levels.