RESUMO
The imidazole alkaloid lepidiline A from the root of Lepidium meyenii has a moderate to low in vitro anticancer effect. Our aim was to extend cytotoxicity investigations against a panel of cancer cells, including multidrug-resistant cancer cells, and multipotent stem cells. Lepidiline A is a N-heterocyclic carbene precursor, therefore a suitable ligand source for metal complexes. Thus, we synthesized lepidiline A and its copper(I), gold(I), and silver(I) complexes and tested them against ovarian, gastrointestinal, breast, and uterine cancer cells and bone marrow-derived and adipose-derived mesenchymal stem cells. Lepidiline A and its copper complex demonstrated moderate cytotoxicity, while silver and gold complexes exhibited significantly enhanced and consistent cytotoxicity against both cancer and stem cell lines. ABCB1 in the multidrug-resistant uterine sarcoma line conferred significant resistance against lepidiline A and the copper-lepidiline A complex, but not against the silver and gold complexes. Our results indicate that only the copper complex induced a significant and universal increase in the production of reactive oxygen species within cells. In summary, binding of metal ions to lepidiline A results in enhanced cytotoxicity with the nature of the metal ion playing a critical role in determining its properties.
RESUMO
The development of copper(II) thiosemicarbazone complexes as potential anticancer agents, possessing dual functionality as inhibitors of R2 ribonucleotide reductase (RNR) and tubulin polymerization by binding at the colchicine site, presents a promising avenue for enhancing therapeutic effectiveness. Herein, we describe the syntheses and physicochemical characterization of four isomeric proligands H2L3-H2L6, with the methylmorpholine substituent at pertinent positions of the pyridine ring, along with their corresponding Cu(II) complexes 3-6. Evidently, the position of the morpholine moiety and the copper(II) complex formation have marked effects on the in vitro antiproliferative activity in human uterine sarcoma MES-SA cells and the multidrug-resistant derivative MES-SA/Dx5 cells. Activity correlated strongly with quenching of the tyrosyl radical (Yâ¢) of mouse R2 RNR protein, inhibition of RNR activity in the cancer cells, and inhibition of tubulin polymerization. Insights into the mechanism of antiproliferative activity, supported by experimental results and molecular modeling calculations, are presented.
Assuntos
Antineoplásicos , Cobre , Morfolinas , Ribonucleotídeo Redutases , Tiossemicarbazonas , Tubulina (Proteína) , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/síntese química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Ribonucleotídeo Redutases/antagonistas & inibidores , Ribonucleotídeo Redutases/metabolismo , Tubulina (Proteína)/metabolismo , Animais , Morfolinas/farmacologia , Morfolinas/química , Morfolinas/síntese química , Cobre/química , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Estrutura-Atividade , Polimerização/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Piridinas/farmacologia , Piridinas/química , Piridinas/síntese química , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química , Ensaios de Seleção de Medicamentos Antitumorais , Modelos MolecularesRESUMO
N-(3-(dimethylamino)propyl-4-(8-hydroxyquinolin-6-yl)benzamide (ML324, HL) is a potent inhibitor of the iron-containing histone demethylase KDM4, a recognized potential target of cancer therapeutics. Herein, we report the proton dissociation and complex formation processes of ML324 with essential metal ions such as Fe(II), Fe(III), Cu(II) and Zn(II) using UV-visible, fluorescence, electron paramagnetic resonance and 1H NMR spectroscopic methods. The electrochemical behaviour of the copper and iron complexes was characterized by cyclic voltammetry and spectroelectrochemistry. The solid phase structure of ML324 analysed by X-ray crystallography is also provided. Based on the solution equilibrium data, ML324 is present in solution in H2L+ form with a protonated dimethylammonium moiety at pH 7.4, and this (N,O) donor bearing ligand forms mono and bis complexes with all the studied metal ions and the tris-ligand species is also observed with Fe(III). At pH 7.4 the metal binding ability of ML324 follows the order: Fe(II) < Zn(II) < Cu(II) < Fe(III). Complexation with iron resulted in a negative redox potential (E'1/2 = -145 mV vs. NHE), further suggesting that the ligand has a preference for Fe(III) over Fe(II). ML324 was tested for its anticancer activity in chemosensitive and resistant human cancer cells overexpressing the efflux pump P-glycoprotein. ML324 exerted similar activity in all tested cells (IC50 = 1.9-3.6 µM). Co-incubation and complexation of the compound with Cu(II) and Zn(II) had no impact on the cytotoxicity of ML324, whereas Fe(III) decreased the toxicity in a concentration-dependent manner, and this effect was more pronounced in the multidrug resistant cells.
Assuntos
Cobre , Compostos Férricos , Humanos , Cobre/química , Compostos Férricos/química , Ligantes , Metais/química , Ferro/química , Íons , Prótons , Compostos Ferrosos , BenzamidasRESUMO
G12C mutant KRas is considered druggable by allele-specific covalent inhibitors due to the nucleophilic character of the oncogenic mutant cysteine at position 12. Discovery of these inhibitors requires the optimization of both covalent and noncovalent interactions. Here, we report covalent fragment screening of our electrophilic fragment library of diverse non-covalent scaffolds equipped with 40 different electrophilic functionalities to identify fragments as suitable starting points targeting Cys12. Screening the library against KRasG12C using Ellman's free thiol assay, followed by protein NMR and cell viability assays, resulted in two potential inhibitor chemotypes. Characterization of these scaffolds in in vitro cellular- and in vivo xenograft models revealed them as promising starting points for covalent drug discovery programs.
Assuntos
Proteínas Proto-Oncogênicas p21(ras) , Humanos , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genéticaRESUMO
Since the first application of natural quinine as an anti-malarial drug, cinchona alkaloids and their derivatives have been exhaustively studied for their biological activity. In our work, we tested 13 cinchona alkaloid organocatalysts, synthesised from quinine. These derivatives were screened against MES-SA and Dx5 uterine sarcoma cell lines for in vitro anticancer activity and to investigate their potential to overcome P-glycoprotein (P-gp) mediated multidrug resistance (MDR). Decorating quinine with hydrogen-bond donor units, such as thiourea and (thio)squaramide, resulted in decreased half-maximal growth inhibition values on both cell lines (1.3-21 µM) compared to quinine and other cinchona alcohols (47-111 µM). Further cytotoxicity studies conducted in the presence of the P-gp inhibitor tariquidar indicated that several analogues, especially cinchona amines and squaramides, but not thiosquaramide, were expelled from MDR cells by P-gp. Similarly to the established P-gp inhibitor quinine, 6 cinchona analogues were shown to inhibit calcein-AM efflux. Interestingly, quinine and didehydroquinine exhibited a marginally increased toxicity against the multidrug resistant Dx5 cells. Collateral sensitivity of the MDR cell line was more pronounced when the cinchona thiosquaramide was complexed with Cu(II) acetate. Based on the results, cinchona derivatives are good anticancer candidates for further drug development.
Assuntos
Alcaloides de Cinchona , Sarcoma , Neoplasias de Tecidos Moles , Neoplasias Uterinas , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Alcaloides de Cinchona/farmacologia , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Quinina/farmacologia , Sarcoma/metabolismo , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/metabolismoRESUMO
A recently proposed strategy to overcome multidrug resistance (MDR) in cancer is to target the collateral sensitivity of otherwise resistant cells. We designed a library of 120 compounds to explore the chemical space around previously identified 8-hydroxyquinoline-derived Mannich bases with robust MDR-selective toxicity. We included compounds to study the effect of halogen and alkoxymethyl substitutions in R5 in combination with different Mannich bases in R7, a shift of the Mannich base from R7 to R5, as well as the introduction of an aromatic moiety. Cytotoxicity tests performed on a panel of parental and MDR cells highlight a strong influence of experimentally determined pKa values of the donor atom moieties, indicating that protonation and metal chelation are important factors modulating the MDR-selective anticancer activity of the studied compounds. Our results identify structural requirements increasing MDR-selective anticancer activity, providing guidelines for the development of more effective anticancer chelators targeting MDR cancer.
Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/química , Antineoplásicos/farmacologia , Quelantes/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Bases de Mannich/química , Bases de Mannich/farmacologia , Oxiquinolina/química , Oxiquinolina/farmacologia , Relação Estrutura-AtividadeRESUMO
An efficient method applying acyl chlorides as reagents was developed for the acylation of the hindered hydroxy group of dialkyl α-hydroxy-benzylphosphonates. The procedure did not require any catalyst. A few acylations were also performed with the SC-enantiomer of dimethyl α-hydroxy-benzylphosphonate, and the optical purity was retained. A part of the acyloxyphosphonates was tested against eight tumor cell lines of different tissue origin at c = 50 µM concentration. The compounds elicited moderate cytostatic effect against breast, skin, prostate, colon, and lung carcinomas; a melanoma cell line; and against Kaposi's sarcoma cell lines. Then, dose-dependent cytotoxicity was assayed, and benzoylation of the α-hydroxy group was identified as a moiety that increases anticancer cytotoxicity across all cell lines. Surprisingly, a few analogues were more toxic to multidrug resistant cancer cell lines, thus evading P-glycoprotein mediated drug extrusion.
Assuntos
Antineoplásicos , Resistência a Múltiplos Medicamentos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Multidrug resistance (MDR) in cancer is one of the major obstacles of chemotherapy. We have recently identified a series of 8-hydroxyquinoline Mannich base derivatives with MDR-selective toxicity, however with limited solubility. In this work, a novel 5-nitro-8-hydroxyquinoline-proline hybrid and its Rh(η5-C5Me5) and Ru(η6-p-cymene) complexes with excellent aqueous solubility were developed, characterized, and tested against sensitive and MDR cells. Complex formation of the ligand with essential metal ions was also investigated using UV-visible, circular dichroism, 1H NMR (Zn(II)), and electron paramagnetic resonance (Cu(II)) spectroscopic methods. Formation of mono and bis complexes was found in all cases with versatile coordination modes, while tris complexes were also formed with Fe(II) and Fe(III) ions, revealing the metal binding affinity of the ligand at pH 7.4: Cu(II) > Zn(II) > Fe(II) > Fe(III). The ligand and its Rh(III) complex displayed enhanced cytotoxicity against the resistant MES-SA/Dx5 and Colo320 human cancer cell lines compared to their chemosensitive counterparts. Both organometallic complexes possess high stability in solution, however the Ru(II) complex has lower chloride ion affinity and slower ligand exchange processes, along with the readiness to lose the arene ring that is likely connected to its inactivity.
Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Compostos Organometálicos , Rutênio , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Prolina , Solubilidade , Ligantes , Resistência a Múltiplos Medicamentos , Compostos Férricos , Rutênio/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Resistencia a Medicamentos Antineoplásicos , Água/química , Íons , Compostos Ferrosos , Compostos Organometálicos/químicaRESUMO
Aims: Due to their significant biological activity, thiosemicarbazones (TSCs) are promising candidates for anticancer therapy. In part, the efficacy of TSCs is linked to their ability to chelate essential metal ions such as copper and iron. Triapine, the best-studied anticancer TSC, has been tested clinically with promising results in hematological diseases. During the past few years, a novel subclass of TSCs with improved anticancer activity was found to induce paraptosis, a recently characterized form of cell death. The aim of this study was to identify structural and chemical properties associated with anticancer activity and paraptosis induction of TSCs. Results: When testing a panel of structurally related TSCs, compounds with nanomolar anticancer activity and paraptosis-inducing properties showed higher copper(II) complex solution stability and a slower reduction rate, which resulted in reduced redox activity. In contrast, TSCs with lower anticancer activity induced higher levels of superoxide that rapidly stimulated superoxide dismutase expression in treated cells, effectively protecting the cells from drug-induced redox stress. Innovation: Consequently, we hypothesize that in the case of close Triapine derivatives, intracellular reduction leads to rapid dissociation of intracellularly formed copper complexes. In contrast, TSCs characterized by highly stable, slowly reducible copper(II) complexes are able to reach new intracellular targets such as the endoplasmic reticulum-resident protein disulfide isomerase. Conclusion: The additional modes of actions observed with highly active TSC derivatives are based on intracellular formation of stable copper complexes, offering a new approach to combat (drug-resistant) cancer cells.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cobre/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Humanos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , SolubilidadeRESUMO
The resistance of tumors against anticancer drugs is a major impediment for chemotherapy. Tumors often develop multidrug resistance as a result of the cellular efflux of chemotherapeutic agents by ABC transporters such as P-glycoprotein (ABCB1/P-gp), Multidrug Resistance Protein 1 (ABCC1/MRP1), or Breast Cancer Resistance Protein (ABCG2/BCRP). By screening a chemolibrary comprising 140 compounds, we identified a set of naturally occurring aurones inducing higher cytotoxicity against P-gp-overexpressing multidrug-resistant (MDR) cells versus sensitive (parental, non-P-gp-overexpressing) cells. Follow-up studies conducted with the P-gp inhibitor tariquidar indicated that the MDR-selective toxicity of azaaurones is not mediated by P-gp. Azaaurone analogs possessing pronounced effects were then designed and synthesized. The knowledge gained from structure-activity relationships will pave the way for the design of a new class of anticancer drugs selectively targeting multidrug-resistant cancer cells.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Benzofuranos/química , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Cães , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células Madin Darby de Rim Canino , Espectroscopia de Ressonância Magnética , Relação Estrutura-AtividadeRESUMO
Clinical evidence shows that following initial response to treatment, drug-resistant cancer cells frequently evolve and, eventually, most tumors become resistant to all available therapies. We compiled a focused library consisting of >500 commercially available or newly synthetized 8-hydroxyquinoline (8OHQ) derivatives whose toxicity is paradoxically increased rather than decreased by the activity of P-glycoprotein (Pgp), a transporter conferring multidrug resistance (MDR). Here, we deciphered the mechanism of action of NSC297366 that shows exceptionally strong Pgp-potentiated toxicity. Treatment of cells with NSC297366 resulted in changes associated with the activity of potent anticancer iron chelators. Strikingly, iron depletion was more pronounced in MDR cells due to the Pgp-mediated efflux of NSC297366-iron complexes. Our results indicate that iron homeostasis can be targeted by MDR-selective compounds for the selective elimination of multidrug resistant cancer cells, setting the stage for a therapeutic approach to fight transporter-mediated drug resistance. SIGNIFICANCE: Modulation of the MDR phenotype has the potential to increase the efficacy of anticancer therapies. These findings show that the MDR transporter is a "double-edged sword" that can be turned against resistant cancer.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Quelantes de Ferro/farmacologia , Ferro/metabolismo , Neoplasias/tratamento farmacológico , Oxiquinolina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Quelantes de Ferro/uso terapêutico , Neoplasias/patologia , Oxiquinolina/análogos & derivados , Oxiquinolina/uso terapêuticoRESUMO
The RASopathy consortium was built from research groups of the Budapest University of Technology and Economics, Eötvös Loránd University, Semmelweis University and two startups: KINETO Lab Ltd. and Fototronic Ltd. The goal was to design and test novel covalent and allele-specific KRAS small molecular inhibitors. KRAS is the most frequently mutated human oncogene which was unsuccessfully targeted until recently. The consortium established G12C-expressing bacterial and human cancer cell models (homo- and heterozygous variants) of lung, colorectal and pancreatic tumors. Using covalent fragment and acrylamide warhead libraries we were able to select novel candidates of small molecular G12C-specific inhibitors which were compared to published best-in-class drug candidates.
Assuntos
Neoplasias , Alelos , Humanos , Mutação , Proteínas Proto-Oncogênicas p21(ras)RESUMO
BACKGROUND: Homologous recombination (HR) repair deficiency arising from defects in BRCA1 or BRCA2 is associated with characteristic patterns of somatic mutations. In this genetic study, we ask whether inactivating mutations in further genes of the HR pathway or the DNA damage checkpoint also give rise to somatic mutation patterns that can be used for treatment prediction. RESULTS: Using whole genome sequencing of an isogenic knockout cell line panel, we find a universal HR deficiency-specific base substitution signature that is similar to COSMIC signature 3. In contrast, we detect different deletion phenotypes corresponding to specific HR mutants. The inactivation of BRCA2 or PALB2 leads to larger deletions, typically with microhomology, when compared to the disruption of BRCA1, RAD51 paralogs, or RAD54. Comparison with the deletion spectrum of Cas9 cut sites suggests that most spontaneously arising genomic deletions are not the consequence of double-strand breaks. Surprisingly, the inactivation of checkpoint kinases ATM and CHK2 has no mutagenic consequences. Analysis of tumor exomes with biallelic inactivating mutations in the investigated genes confirms the validity of the cell line models. We present a comprehensive analysis of sensitivity of the investigated mutants to 13 therapeutic agents for the purpose of correlating genomic mutagenic phenotypes with drug sensitivity. CONCLUSION: Our results suggest that no single genomic mutational class shows perfect correlation with sensitivity to common treatments, but the contribution of COSMIC signature 3 to base substitutions, or a combined measure of different features, may be reasonably good at predicting platinum and PARP inhibitor sensitivity.
Assuntos
Genes cdc , Mutagênese , Variantes Farmacogenômicos , Inibidores de Poli(ADP-Ribose) Polimerases , Reparo de DNA por Recombinação/genética , Animais , Linhagem Celular , Galinhas , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Mutação PuntualRESUMO
Membrane transporters play an important role in the absorption, distribution, metabolism and excretion of drugs. The cellular accumulation of many drugs is the result of the net function of efflux and influx transporters. Efflux transporters such as P-glycoprotein/ABCB1 have been shown to confer multidrug resistance in cancer. Although expression of uptake transporters has been confirmed in cancer cells, their role in chemotherapy response has not been systematically investigated. In the present study we have adapted a fluorescence-based cytotoxic assay to characterize the influence of key drug-transporters on the toxicity of approved anticancer drugs. Co-cultures of fluorescently labeled parental and transporter-expressing cells (expressing ABCB1, ABCG2 or OATP2B1) were screened against 101 FDA-approved anticancer drugs, using a novel, automated, triple fluorescence-based cytotoxicity assay. By measuring the survival of parental and transporter-expressing cells in co-cultures, we identify those FDA-approved anticancer drugs, whose toxicity is influenced by ABCB1, ABCG2 or OATP2B1. In addition to confirming known substrates of ABCB1 and ABCG2, the fluorescence-based cytotoxicity assays identified anticancer agents whose toxicity was increased in OATP2B1 expressing cells. Interaction of these compounds with OATP2B1 was verified in dedicated transport assays using cell-impermeant fluorescent substrates. Understanding drug-transporter interactions is needed to increase the efficacy of chemotherapeutic agents. Our results highlight the potential of the fluorescence-based HT screening system for identifying transporter substrates, opening the way for the design of therapeutic approaches based on the inhibition or even the exploitation of transporters in cancer cells.
Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Proteínas Luminescentes/genética , Transportadores de Ânions Orgânicos/metabolismo , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Simulação por Computador , Citometria de Fluxo , Corantes Fluorescentes , Proteínas de Fluorescência Verde/genética , Humanos , Transportadores de Ânions Orgânicos/genética , Especificidade por Substrato , Transdução Genética , Proteína Vermelha FluorescenteRESUMO
Drug resistant tuberculosis (TB) is a major worldwide health problem. In addition to the bacterial mechanisms, human drug transporters limiting the cellular accumulation and the pharmacological disposition of drugs also influence the efficacy of treatment. Mycobacterium tuberculosis topoisomerase-I (MtTopo-I) is a promising target for antimicrobial treatment. In our previous work we have identified several hit compounds targeting the MtTopo-I by in silico docking. Here we expand the scope of the compounds around three scaffolds associated with potent MtTopo-I inhibition. In addition to measuring the effect of newly generated compounds on MtTopo-I activity, we characterized the compounds' antimicrobial activity, toxicity in human cells, and interactions with human multidrug transporters. Some of the newly developed MtTopo-I inhibitors have strong antimicrobial activity and do not harm mammalian cells. Moreover, our studies revealed significant human ABC drug transporter interactions for several MtTopo-I compounds that may modify their ADME-Tox parameters and cellular effects. Promising new drug candidates may be selected based on these studies for further anti-TB drug development.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Mycobacterium tuberculosis/enzimologia , Inibidores da Topoisomerase I/metabolismo , Inibidores da Topoisomerase I/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/química , Animais , Linhagem Celular , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Inibidores da Topoisomerase I/toxicidadeRESUMO
Cyclic NGR peptides as homing devices are good candidates for the development of drug conjugates for targeted tumor therapy. In our previous study we reported that the Dau=Aoa-GFLGK(c[KNGRE]-GG-)-NH2 conjugate has a significant antitumor activity against both CD13+ HT-1080 human fibrosarcoma and CD13- but integrin positive HT-29 human colon adenocarcinoma cells. However, it seems that the free ε-amino group of Lys in the cycle is not necessary for the biological activity. Therefore, we developed novel cyclic NGR peptide-daunomycin conjugates in which Lys was replaced by different amino acids (Ala, Leu, Nle, Pro, Ser). The exchange of the Lys residue in the cycle simplified the cyclization step and resulted in a higher yield. The new conjugates showed lower chemostability against deamidation of Asn than the control compound, thus they had lower selectivity to CD13+ cells. However, the cellular uptake and cytotoxic effect of Dau=Aoa-GFLGK(c[NleNGRE]-GG-)-NH2 was higher in comparison to the control especially on HT-29 cells. Therefore, this conjugate is more suitable for drug targeting with dual targeting property.
RESUMO
Success of cancer treatment is often hampered by the emergence of multidrug resistance (MDR) mediated by P-glycoprotein (ABCB1/Pgp). Doxorubicin (DOX) is recognized by Pgp and therefore it can induce therapy resistance in breast cancer patients. In this study our aim was to evaluate the susceptibility of the pegylated liposomal formulation of doxorubicin (PLD/Doxil®/Caelyx®) to MDR. We show that cells selected to be resistant to DOX are cross-resistant to PLD and PLD is also ineffective in an allograft model of doxorubicin-resistant mouse B-cell leukemia. In contrast, PLD was far more efficient than DOX as reflected by a significant increase of both relapse-free and overall survival of Brca1-/-;p53-/- mammary tumor bearing mice. Increased survival could be explained by the delayed onset of drug resistance. Consistent with the higher Pgp levels needed to confer resistance, PLD administration was able to overcome doxorubicin insensitivity of the mouse mammary tumors. Our results indicate that the favorable pharmacokinetics achieved with PLD can effectively overcome Pgp-mediated resistance, suggesting that PLD therapy could be a promising strategy for the treatment of therapy-resistant breast cancer patients.
Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/análogos & derivados , Leucemia de Células B/tratamento farmacológico , Neoplasias Mamárias Experimentais/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leucemia de Células B/patologia , Masculino , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Knockout , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Taxa de SobrevidaRESUMO
Peptides containing the asparagine-glycine-arginine (NGR) motif are recognized by CD13/aminopeptidase N (APN) receptor isoforms that are selectively overexpressed in tumor neovasculature. Spontaneous decomposition of NGR peptides can result in isoAsp derivatives, which are recognized by RGD-binding integrins that are essential for tumor metastasis. Peptides binding to CD13 and RGD-binding integrins provide tumor-homing, which can be exploited for dual targeted delivery of anticancer drugs. We synthesized small cyclic NGR peptide-daunomycin conjugates using NGR peptides of varying stability (c[KNGRE]-NH2, Ac-c[CNGRC]-NH2 and the thioether bond containing c[CH2-CO-NGRC]-NH2, c[CH2-CO-KNGRC]-NH2). The cytotoxic effect of the novel cyclic NGR peptide-Dau conjugates were examined in vitro on CD13 positive HT-1080 (human fibrosarcoma) and CD13 negative HT-29 (human colon adenocarcinoma) cell lines. Our results confirm the influence of structure on the antitumor activity and dual acting properties of the conjugates. Attachment of the drug through an enzyme-labile spacer to the C-terminus of cyclic NGR peptide resulted in higher antitumor activity on both CD13 positive and negative cells as compared to the branching versions.
Assuntos
Antibióticos Antineoplásicos/química , Daunorrubicina/química , Oligopeptídeos/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Ciclização , Daunorrubicina/farmacologia , Humanos , Oligopeptídeos/farmacologia , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
There is a constant need for new therapies against multidrug-resistant (MDR) cancer. Natural compounds are a promising source of novel anticancer agents. We recently showed that protoflavones display activity in MDR cancer cell lines that overexpress the P-glycoprotein (P-gp) drug efflux pump. In this study, 52 protoflavones, including 22 new derivatives, were synthesized and tested against a panel of drug-sensitive parental cells and their MDR derivatives obtained by transfection with the human ABCB1 or ABCG2 genes, or by adaptation to chemotherapeutics. With the exception of protoapigenone, identified as a weak ABCG2 substrate, all protoflavones bypass resistance conferred by these two transporters. The majority of the compounds were found to exhibit mild to strong (up to 13-fold) selectivity against the MCF-7Dox and KB-V1 cell lines, but not to transfected MDR cells engineered to overexpress the MDR transporters. Our results suggest that protoflavones can overcome MDR cancer by evading P-gp-mediated efflux.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Flavonas/química , Flavonas/síntese química , Flavonas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Flavonas/metabolismo , Humanos , Concentração Inibidora 50 , Relação Estrutura-AtividadeRESUMO
Despite significant progress, resistance to chemotherapy is still the main reason why cancer remains a deadly disease. An attractive strategy is to target the collateral sensitivity of otherwise multidrug resistant (MDR) cancer. In this study, our aim was to catalog various compounds that were reported to elicit increased toxicity in P-glycoprotein (Pgp)-overexpressing MDR cells. We show that the activity of most of the serendipitously identified compounds reported to target MDR cells is in fact cell-line specific, and is not influenced significantly by the function of Pgp. In contrast, novel 8-hydroxyquinoline derivatives that we identify in the National Cancer Institute (NCI) drug repository possess a robust Pgp-dependent toxic activity across diverse cell lines. Pgp expression associated with the resistance of the doxorubicin-resistant Brca1-/-;p53-/- spontaneous mouse mammary carcinoma cells could be eliminated by a single treatment with NSC57969, suggesting that MDR-selective compounds can effectively revert the MDR phenotype of cells expressing Pgp at clinically relevant levels. The discovery of new MDR-selective compounds shows the potential of this emerging technology and highlights the 8-hydroxyquinoline scaffold as a promising starting point for the development of compounds targeting the Achilles heel of drug-resistant cancer. Mol Cancer Ther; 16(1); 45-56. ©2016 AACR.