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1.
Cancers (Basel) ; 15(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37174093

RESUMO

The brain is one of the most common metastatic sites among breast cancer patients, especially in those who have Her2-positive or triple-negative tumors. The brain microenvironment has been considered immune privileged, and the exact mechanisms of how immune cells in the brain microenvironment contribute to brain metastasis remain elusive. In this study, we found that neutrophils are recruited and influenced by c-Met high brain metastatic cells in the metastatic sites, and depletion of neutrophils significantly suppressed brain metastasis in animal models. Overexpression of c-Met in tumor cells enhances the secretion of a group of cytokines, including CXCL1/2, G-CSF, and GM-CSF, which play critical roles in neutrophil attraction, granulopoiesis, and homeostasis. Meanwhile, our transcriptomic analysis demonstrated that conditioned media from c-Met high cells significantly induced the secretion of lipocalin 2 (LCN2) from neutrophils, which in turn promotes the self-renewal of cancer stem cells. Our study unveiled the molecular and pathogenic mechanisms of how crosstalk between innate immune cells and tumor cells facilitates tumor progression in the brain, which provides novel therapeutic targets for treating brain metastasis.

2.
Lung Cancer ; 178: 37-46, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36773459

RESUMO

The treatment regimen of non-small cell lung cancer (NSCLC) has drastically changed owing to the superior anti-cancer effects generated by the immune-checkpoint blockade (ICB). However, only a subset of patients experience benefit after receiving ICBs. Therefore, it is of paramount importance to increase the response rate by elucidating the underlying molecular mechanisms and identifying novel therapeutic targets to enhance the efficacy of IBCs in non-responders. We analyzed the progression-free survival (PFS) and overall survival (OS) of 295 NSCLC patients who received anti-PD-1 therapy by segregating them with multiple clinical factors including sex, age, race, smoking history, BMI, tumor grade and subtype. We also identified key signaling pathways and mutations that are enriched in patients with distinct responses to ICB by gene set enrichment analysis (GSEA) and mutational analyses. We found that former and current smokers have a higher response rate to anti-PD-1 treatment than non-smokers. GSEA results revealed that oxidative phosphorylation (OXPHOS) and mitochondrial related pathways are significantly enriched in both responders and smokers, suggesting a potential role of cellular metabolism in regulating immune response to ICB. We also demonstrated that all-trans retinoic acid (ATRA) which enhances mitochondrial function significantly enhanced the efficacy of anti-PD-1 treatment in vivo. Our clinical and bioinformatics based analyses revealed a connection between smoking induced metabolic switch and the response to immunotherapy, which can be the basis for developing novel combination therapies that are beneficial to never smoked NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fumar Cigarros , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fosforilação Oxidativa , Fumar Cigarros/efeitos adversos , Biogênese de Organelas , Inibidores de Checkpoint Imunológico/uso terapêutico , Antígeno B7-H1/metabolismo
3.
Sci Transl Med ; 14(648): eabh1261, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35675434

RESUMO

Tumor evasion of immune destruction is associated with the production of immunosuppressive adenosine in the tumor microenvironment (TME). Anticancer therapies can trigger adenosine triphosphate (ATP) release from tumor cells, causing rapid formation of adenosine by the ectonucleotidases CD39 and CD73, thereafter exacerbating immunosuppression in the TME. The goal of this study was to develop an approach to facilitate cancer therapy-induced immunogenic cell death including ATP release and to limit ATP degradation into adenosine, in order to achieve durable antitumor immune response. Our approach was to construct reactive oxygen species (ROS)-producing nanoparticles that carry an ectonucleotidase inhibitor ARL67156 by electronic interaction and phenylboronic ester. Upon near-infrared irradiation, nanoparticle-produced ROS induced ATP release from MOC1 cancer cells in vitro and triggered the cleavage of phenylboronic ester, facilitating the release of ARL67156 from the nanoparticles. ARL67156 prevented conversion of ATP to adenosine and enhanced anticancer immunity in an MOC1-based coculture model. We tested this approach in mouse tumor models. Nanoparticle-based ROS-responsive drug delivery reprogramed the immunogenic landscape in tumors, eliciting tumor-specific T cell responses and tumor regression, conferring long-term survival in mouse models. We demonstrated that TME reprograming sets the stage for response to anti-programmed cell death protein 1 (PD1) immunotherapy, and the combination resulted in tumor regression in a 4T1 breast cancer mouse model that was resistant to PD1 blockade. Furthermore, our approach also induced immunological effects in patient-derived organotypic tumor spheroid model, suggesting potential translation of our nanoparticle approach for treating human cancers.


Assuntos
Nanopartículas , Neoplasias , Adenosina/farmacologia , Adenosina/uso terapêutico , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Ésteres , Humanos , Terapia de Imunossupressão , Camundongos , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio , Microambiente Tumoral
4.
Nat Nanotechnol ; 17(2): 206-216, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34916656

RESUMO

Malignant pleural effusion (MPE) is indicative of terminal malignancy with a uniformly fatal prognosis. Often, two distinct compartments of tumour microenvironment, the effusion and disseminated pleural tumours, co-exist in the pleural cavity, presenting a major challenge for therapeutic interventions and drug delivery. Clinical evidence suggests that MPE comprises abundant tumour-associated myeloid cells with the tumour-promoting phenotype, impairing antitumour immunity. Here we developed a liposomal nanoparticle loaded with cyclic dinucleotide (LNP-CDN) for targeted activation of stimulators of interferon genes signalling in macrophages and dendritic cells and showed that, on intrapleural administration, they induce drastic changes in the transcriptional landscape in MPE, mitigating the immune cold MPE in both effusion and pleural tumours. Moreover, combination immunotherapy with blockade of programmed death ligand 1 potently reduced MPE volume and inhibited tumour growth not only in the pleural cavity but also in the lung parenchyma, conferring significantly prolonged survival of MPE-bearing mice. Furthermore, the LNP-CDN-induced immunological effects were also observed with clinical MPE samples, suggesting the potential of intrapleural LNP-CDN for clinical MPE immunotherapy.


Assuntos
Antígeno B7-H1/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Derrame Pleural Maligno/tratamento farmacológico , Imunidade Adaptativa/efeitos dos fármacos , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/química , Antígeno B7-H1/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Humanos , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/farmacologia , Imunidade Inata/efeitos dos fármacos , Imunoterapia , Interferons/genética , Camundongos , Nanopartículas/uso terapêutico , Cavidade Pleural/efeitos dos fármacos , Cavidade Pleural/imunologia , Cavidade Pleural/patologia , Derrame Pleural Maligno/genética , Derrame Pleural Maligno/imunologia , Derrame Pleural Maligno/patologia , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Cancer Res ; 81(14): 3890-3904, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34083249

RESUMO

Obesity and poor diet often go hand-in-hand, altering metabolic signaling and thereby impacting breast cancer risk and outcomes. We have recently demonstrated that dietary patterns modulate mammary microbiota populations. An important and largely open question is whether the microbiome of the gut and mammary gland mediates the dietary effects on breast cancer. To address this, we performed fecal transplants between mice on control or high-fat diets (HFD) and recorded mammary tumor outcomes in a chemical carcinogenesis model. HFD induced protumorigenic effects, which could be mimicked in animals fed a control diet by transplanting HFD-derived microbiota. Fecal transplants altered both the gut and mammary tumor microbiota populations, suggesting a link between the gut and breast microbiomes. HFD increased serum levels of bacterial lipopolysaccharide (LPS), and control diet-derived fecal transplant reduced LPS bioavailability in HFD-fed animals. In vitro models of the normal breast epithelium showed that LPS disrupts tight junctions (TJ) and compromises epithelial permeability. In mice, HFD or fecal transplant from animals on HFD reduced expression of TJ-associated genes in the gut and mammary gland. Furthermore, infecting breast cancer cells with an HFD-derived microbiome increased proliferation, implicating tumor-associated bacteria in cancer signaling. In a double-blind placebo-controlled clinical trial of patients with breast cancer administered fish oil supplements before primary tumor resection, dietary intervention modulated the microbiota in tumors and normal breast tissue. This study demonstrates a link between the gut and breast that mediates the effect of diet on cancer. SIGNIFICANCE: This study demonstrates that diet shifts the microbiome in the gut and the breast tumor microenvironment to affect tumorigenesis, and oral dietary interventions can modulate the tumor microbiota in patients with breast cancer. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/14/3890/F1.large.jpg.


Assuntos
Mama/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Animais , Carcinogênese , Feminino , Humanos , Camundongos , Microbiota , Transdução de Sinais
6.
Mol Cell ; 80(2): 263-278.e7, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33022274

RESUMO

Cancer metastasis accounts for the major cause of cancer-related deaths. How disseminated cancer cells cope with hostile microenvironments in secondary site for full-blown metastasis is largely unknown. Here, we show that AMPK (AMP-activated protein kinase), activated in mouse metastasis models, drives pyruvate dehydrogenase complex (PDHc) activation to maintain TCA cycle (tricarboxylic acid cycle) and promotes cancer metastasis by adapting cancer cells to metabolic and oxidative stresses. This AMPK-PDHc axis is activated in advanced breast cancer and predicts poor metastasis-free survival. Mechanistically, AMPK localizes in the mitochondrial matrix and phosphorylates the catalytic alpha subunit of PDHc (PDHA) on two residues S295 and S314, which activates the enzymatic activity of PDHc and alleviates an inhibitory phosphorylation by PDHKs, respectively. Importantly, these phosphorylation events mediate PDHc function in cancer metastasis. Our study reveals that AMPK-mediated PDHA phosphorylation drives PDHc activation and TCA cycle to empower cancer cells adaptation to metastatic microenvironments for metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Ciclo do Ácido Cítrico , Complexo Piruvato Desidrogenase/metabolismo , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Fosforilação , Fosfosserina/metabolismo , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida
7.
Transl Oncol ; 13(7): 100780, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32428837

RESUMO

Acute myeloid leukemia (AML) is an aggressive malignancy with poor outcomes. Nucleoside analogs are subject to resistance mechanisms including downregulation of equilibrative nucleoside transporter (ENT1) and deoxycytidine kinase (dCK). KPC34 is a novel phospholipid mimetic that when cleaved by phospholipase C (PLC) liberates gemcitabine monophosphate and a diacylglycerol mimetic that inhibits the classical isoforms of protein kinase C (PKC). KPC34 acts independently of ENT1 and dCK. KPC34 was active against all AML cell lines tested with IC50s in the nanomolar range. Enforced expression of PLC increased response to KPC34 in vivo. In an orthotopic, xenograft model, KPC34 treatment resulted in a significant increase in survival compared to control animals and those treated with high-dose cytarabine. In a PDX model with activated PKC, there was a significant survival benefit with KPC34, and at progression, there was attenuation of PKC activation in the resistant cells. In contrast, KPC34 was ineffective against a syngeneic, orthotopic AML model without activated PKC. However, when cells from that model were forced to express PKC, there were significantly increased sensitivity in vitro and survival benefit in vivo. These data suggest that KPC34 is active against AML and that the presence of activated PKC can be a predictive biomarker.

8.
Biopreserv Biobank ; 17(5): 452-457, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31194582

RESUMO

The tissue microarray (TMA) is a powerful tool for cancer biomarker discovery and validation. Tens to hundreds of samples can be evaluated simultaneously for molecular marker status at the protein or nucleic acid level. Although fully automated or semiautomated technologies for TMA creation provide excellent precision with respect to core transfer, they do not obviate the need for technical expertise to successfully generate high-quality TMA blocks and derivative sections. We have leveraged our expanding bank of formalin-fixed paraffin embedded paired tumor and normal tissues in our academic cancer center to provide a rich source of input material for cancer research TMAs. In this study, we report a stepwise optimization of TMA generation parameters, including paraffin wax selection, tempering protocol, and sectioning conditions, to achieve the best ribbon sectioning.


Assuntos
Neoplasias/metabolismo , Análise Serial de Tecidos/métodos , Biomarcadores Tumorais/metabolismo , Formaldeído , Humanos , Inclusão em Parafina , Fixação de Tecidos
9.
PLoS One ; 12(6): e0179798, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28644853

RESUMO

Philadelphia chromosome positive B cell acute lymphoblastic leukemia (Ph+ ALL) is an aggressive cancer of the bone marrow. The addition of tyrosine kinase inhibitors (TKIs) has improved outcomes but many patients still suffer relapse and novel therapeutic agents are needed. KPC34 is an orally available, novel phospholipid conjugate of gemcitabine, rationally designed to overcome multiple mechanisms of resistance, inhibit the classical and novel isoforms of protein kinase C, is able to cross the blood brain barrier and is orally bioavailable. KPC34 had an IC50 in the nanomolar range against multiple ALL cell lines tested but was lowest for Ph+ lines. In mice bearing either naïve or resistant Ph+ ALL, KPC34 treatment resulted in significantly improved survival compared to cytarabine and gemcitabine. Treatment with KPC34 and doxorubicin was more effective than doxorubicin and cytarabine. Mice with recurrence of their ALL after initial treatment with cytarabine and doxorubicin saw dramatic improvements in hind limb paralysis after treatment with KPC34 demonstrating activity against established CNS disease. Consistent with this KPC34 was better than gemcitabine at reducing CNS leukemic burden. These promising pre-clinical results justify the continued development of KPC34 for the treatment of Ph+ALL.


Assuntos
Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Glicerofosfatos/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Animais , Antineoplásicos/toxicidade , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Citarabina/farmacologia , Dano ao DNA/efeitos dos fármacos , Desoxicitidina/farmacologia , Desoxicitidina/toxicidade , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Glicerofosfatos/toxicidade , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transplante de Neoplasias , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Distribuição Aleatória , Carga Tumoral/efeitos dos fármacos , Gencitabina
10.
Inorg Chem ; 54(7): 3316-24, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25793564

RESUMO

Thiourea-modified 3-chloro-4-fluoroanilino-quinazoline derivatives have been studied as potential receptor-targeted carrier ligands in linear gold(I) complexes. The molecules mimic the epidermal growth factor receptor (EGFR) tyrosine kinase-targeted inhibitor gefitinib. Thiourea groups were either directly attached to quinazoline-C6 (compounds 4, 5, and 7) or linked to this position via a flexible ethylamino chain (compound 9). Compound 7 acts as a thiourea-S/quinazoline-N1 mixed-donor ligand, giving the unexpected dinuclear complex [{Au(µ-7-S,N)}2]X2 (X = Cl(-), SCN(-)) (12a,b) (X-ray crystallography, electrospray mass spectrometry). Derivative 9 forms a stable linear complex, [Au(PEt3)(9-S)](NO3) (13). The biological activity of the carrier ligands and corresponding gold(I) complexes was studied in NCI-H460 and NCI-H1975 lung cancer cells. Compound 9 partially overcomes resistance to gefitinib in NCI-H1975, a lung cancer cell line characterized by a L858R/T790M mutation in EGFR (IC50 values of 1.7 and 30 µM, respectively). The corresponding gold complex (13) maintains activity in the low-micromolar concentration range similar to the metal-free carrier. Compound 9 and the corresponding [Au(PEt3)] complex, 13, inhibit EGFR kinase-mediated phosphorylation with sub-micromolar IC50 values similar to those observed for gefitinib under the same assay conditions. Potential mechanisms of action and reactions in biological media of this new type of hybrid agent, as well as shortcomings of the current design are discussed.


Assuntos
Complexos de Coordenação/química , Ouro/química , Inibidores de Proteínas Quinases/síntese química , Tioureia/química , Afatinib , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , Relação Dose-Resposta a Droga , Gefitinibe , Humanos , Concentração Inibidora 50 , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/síntese química , Quinazolinas/farmacologia , Tioureia/síntese química , Tioureia/farmacologia
11.
Chemistry ; 20(49): 16174-87, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25302716

RESUMO

Platinum-acridine hybrid agents show low-nanomolar potency in chemoresistant non-small cell lung cancer (NSCLC), but high systemic toxicity in vivo. To reduce the promiscuous genotoxicity of these agents and improve their pharmacological properties, a modular build-click-screen approach was used to evaluate a small library of twenty hybrid agents containing truncated and extended chromophores of varying basicities. Selected derivatives were resynthesized and tested in five NSCLC cell lines representing large cell, squamous cell, and adenocarcinomas. 7-Aminobenz[c]acridine was identified as a promising scaffold in a hybrid agent (P1-B1) that maintained submicromolar activity in several of the DNA-repair proficient and p53-mutant cancer models, while showing improved tolerability in mice by 32-fold compared to the parent platinum-acridine (P1-A1). The distribution and DNA/RNA adduct levels produced by the acridine- and benz[c]acridine-based analogues in NCI-H460 cells (confocal microscopy, ICP-MS), and their ability to bind G-quadruplex forming DNA sequences (CD spectroscopy, HR-ESMS) were studied. P1-B1 emerges as a less genotoxic, more tolerable, and potentially more target-selective hybrid agent than P1-A1.


Assuntos
Acridinas/química , Antineoplásicos/química , Desenho de Fármacos , Substâncias Intercalantes/química , Compostos Organoplatínicos/química , Acridinas/farmacologia , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Adutos de DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Quadruplex G/efeitos dos fármacos , Humanos , Substâncias Intercalantes/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos , Compostos Organoplatínicos/farmacologia , Relação Estrutura-Atividade
12.
Chemistry ; 20(49): 16164-73, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25303639

RESUMO

Using a versatile synthetic approach, a new class of potential ester prodrugs of highly potent, but systemically too toxic, platinum-acridine anticancer agents was generated. The new hybrids contain a hydroxyl group, which has been masked with a cleavable lipophilic acyl moiety. Both butanoic (butyric) and bulkier 2-propanepentanoic (valproic) esters were introduced. The goals of this design were to improve the drug-like properties (e.g., logD) and to reduce the systemic toxicity of the pharmacophore. Two distinct pathways by which the target compounds undergo effective ester hydrolysis, the proposed activating step, have been confirmed: platinum-assisted, self-immolative ester cleavage in a low-chloride environment (LC-ESMS, NMR spectroscopy) and enzymatic cleavage by human carboxylesterase-2 (hCES-2) (LC-ESMS). The valproic acid ester derivatives are the first example of a metal-containing agent cleavable by the prodrug-converting enzyme. They show excellent chemical stability and reduced systemic toxicity. Preliminary results from screening in lung adenocarcinoma cell lines (A549, NCI-H1435) suggest that the mechanism of the valproic esters may involve intracellular deesterification.


Assuntos
Antineoplásicos/química , Platina/química , Pró-Fármacos/química , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Hidrólise , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Platina/metabolismo , Platina/farmacologia , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Ácido Valproico/química , Ácido Valproico/metabolismo , Ácido Valproico/farmacologia
13.
J Biol Inorg Chem ; 19(3): 415-26, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24407462

RESUMO

Confocal fluorescence microscopy was used to study a platinum-based anticancer agent in intact NCI-H460 lung cancer cells. Orthogonal copper-catalyzed azide-alkyne cycloaddition (click) reactions were used to simultaneously determine the cell-cycle-specific localization of the azide-functionalized platinum-acridine agent 1 and monitor its effects on nucleic acid metabolism. Copper-catalyzed postlabeling showed advantages over copper-free click chemistry using a dibenzocyclooctyne (DIBO)-modified reporter dye, which produced high background levels in microscopic images and failed to efficiently label platinum adducts in chromatin. Compound 1 was successfully labeled with the fluorophore DIBO to yield 1* (characterized by in-line high-performance liquid chromatography/electrospray mass spectrometry). 1 and 1* show a high degree of colocalization in the confocal images, but the ability of 1* to target the (compacted) chromatin was markedly reduced, most likely owing to the steric bulk introduced by the DIBO tag. Nuclear platinum levels correlated inversely with the ability of the cells to synthesize DNA and cause cell cycle arrest, as confirmed by bivariate flow cytometry analysis. In addition, a decrease in the level of cellular transcription, shrinkage of the nucleolar regions, and redistribution of RNA into the cytosol were observed. Postlabeling in conjunction with colocalization experiments is a useful tool for studying the cell killing mechanism of this type of DNA-targeted agent.


Assuntos
Antineoplásicos/metabolismo , Ciclo Celular/fisiologia , Química Click/métodos , DNA/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Platina/metabolismo , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , DNA/genética , Citometria de Fluxo/métodos , Humanos , Platina/administração & dosagem , Platina/química
16.
J Med Chem ; 55(22): 10198-203, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23074987

RESUMO

An efficient screening method was developed for functionalized DNA-targeted platinum-containing hybrid anticancer agents based on metal-mediated amine-to-nitrile addition, a form of "click" chemistry. The goal of the study was to generate platinum-acridine agents for their use as cytotoxic "warheads" in targeted and multifunctional therapies. This was achieved by introducing hydroxyl, carboxylic acid, and azide functionalities in the acridine linker moiety and by varying the nonleaving groups attached to platinum. The assay, which was based on microscale reactions between 6 platinum-nitrile complexes and 10 acridine derivatives, yielded a small library of 60 platinum-acridines. Reactions were monitored, and product mixtures were quantitatively analyzed by automated in-line high-performance liquid chromatography-electrospray mass spectrometry (LC-ESMS) analysis and subjected to cell viability screening using a nonradioactive cell proliferation assay. The new prescreening methodology proves to be a powerful tool for establishing structure-activity relationships and for identifying target compounds.


Assuntos
Acridinas/farmacologia , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , DNA/química , Neoplasias/tratamento farmacológico , Platina/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Acridinas/química , Antineoplásicos/química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Platina/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
17.
J Med Chem ; 55(17): 7817-27, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22871158

RESUMO

The synthesis of platinum-acridine hybrid agents containing carboxylic acid ester groups is described. The most active derivatives and the unmodified parent compounds showed up to 6-fold higher activity in ovarian cancer (OVCAR-3) and breast cancer (MCF-7, MDA-MB-231) cell lines than cisplatin. Inhibition of cell proliferation at nanomolar concentrations was observed in pancreatic (PANC-1) and nonsmall cell lung cancer cells (NSCLC, NCI-H460) of 80- and 150-fold, respectively. Introduction of the ester groups did not affect the cytotoxic properties of the hybrids, which form the same monofunctional-intercalative DNA adducts as the parent compounds, as demonstrated in a plasmid unwinding assay. In-line high-performance liquid chromatography and electrospray mass spectrometry (LC-ESMS) shows that the ester moieties undergo platinum-mediated hydrolysis in a chloride concentration-dependent manner to form carboxylate chelates. Potential applications of the chloride-sensitive ester hydrolysis as a self-immolative release mechanism for tumor-selective delivery of platinum-acridines are discussed.


Assuntos
Ácidos Carboxílicos/química , Platina/química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Ésteres , Humanos , Espectrometria de Massas por Ionização por Electrospray , Água
18.
Metallomics ; 4(7): 645-52, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22456976

RESUMO

High-performance liquid chromatography in conjunction with electrospray mass spectrometry (LC-ESMS) was used to structurally characterize the adducts formed by the platinum-acridine agent [PtCl(en)(N-(2-(acridin-9-ylamino)ethyl)-N-methylpropionimidamide)](NO(3))(2) (compound 1) in cell-free DNA. Compound 1 forms monofunctional adducts exclusively with guanine, based on the fragments identified in enzymatic digests (dG*, dGMP*, dApG*, and dTpG*, where the asterisk denotes bound drug). The time course of accumulation and DNA adduct formation of compound 1 and the clinical drug cisplatin in NCI-H460 lung cancer cells at physiologically relevant drug concentrations (0.1 µM) was studied by inductively-coupled plasma mass spectrometry (ICP-MS). Compound 1 accumulates rapidly in cells and reaches intracellular levels of up to 60-fold higher than those determined for cisplatin. The hybrid agent shows unusually high DNA binding levels: while cisplatin adducts form at a maximum frequency of 5 adducts per 10(6) nucleotides, compound 1 produces 25 adducts per 10(6) nucleotides after only 3 h of continuous incubation with the lung cancer cells. The high overall levels of compound 1 in the cells and in cellular DNA over the entire 12-h treatment period translate into a rapid decrease in cell viability. Possible implications of these findings for the mechanism of action of compound 1 and the agent's potential to overcome tumor resistance to cisplatin are discussed.


Assuntos
Acridinas/farmacologia , Antineoplásicos/farmacologia , Dano ao DNA , Neoplasias Pulmonares/patologia , Platina/farmacologia , Acridinas/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistema Livre de Células , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Cisplatino/química , Cisplatino/farmacologia , Adutos de DNA/química , Adutos de DNA/metabolismo , DNA de Neoplasias/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Platina/química , Espectrometria de Massas por Ionização por Electrospray
19.
ACS Med Chem Lett ; 2(9): 687-691, 2011 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-21927647

RESUMO

The formation of unusual seven-membered, sterically overloaded chelates [Pt(en)(L/L´)](NO(3))(2) (4a/4b) from the corresponding potent hybrid antitumor agents [PtCl(en)(LH/L´H)](NO(3))(2) (3a/3b) is described, where en is ethane-1,2-diamine and L(H) and L´(H) are (protonated) N-(2-(acridin-9-ylamino)ethyl)-N-methylpropionimidamide and N-(2-(acridin-9-ylamino)ethyl)-N-methylacetimidamide, respectively. Compounds 3a and 3b inhibit H460 lung cancer cell proliferation with IC(50) values of 12 ± 2 nM and 2.8 ± 0.3 nM, respectively. The new derivative 3b proves to be not only the most cytotoxic platinum-acridine hybrid of this kind, but also one of the most potent platinum-based anticancer agents described to date. The chelates 4a and 4b do not undergo ligand substitution reactions with nucleobase nitrogen and cysteine sulfur and do not intercalate into DNA. Despite their inertness, the two chelates appear to maintain micromolar activity in H460 cells. The results are discussed in the context of potential DNA-mediated and DNA-independent cell kill mechanisms and the potential use of the chelates as prodrugs.

20.
ACS Med Chem Lett ; 2(11): 870-874, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22328962

RESUMO

The platinum-acridine anti-cancer agent [PtCl(en)(LH)](NO(3))(2) (1) (en = ethane-1,2-diamine, LH = N-(2-(acridin-9-ylamino)ethyl)-N-methylpropionimidamide, acridinium cation) and the clinical drug cisplatin were studied in chemoresistant non-small cell lung cancer (NSCLC) cell lines for their cytotoxic potency and cell-kill mechanisms. In the three cell lines tested (NCI-H460, NCI-H522, and NCI-H1435) compound 1 shows a pronounced cytotoxic enhancement of 40-200-fold compared to cisplatin at inhibitory concentrations reaching the low-nanomolar range. Based on changes in cell adhesion and cell morphology, monitored in real time by impedance measurements, compound 1 kills NCI-H460 cells significantly more efficiently than cisplatin at equitoxic concentrations. Flow cytometry analysis of NCI-H460 cells reveals a robust S-phase arrest of cells treated with compound 1, whereas cells treated with cisplatin progress to G2/M of the cell cycle. A pronounced inhibition of DNA replication in 75% of viable cells is observed in NCI-H460 cells treated with compound 1 at an IC(90) molar concentration for 48 h, based on the reduced incorporation of the fluorophore-clickable nucleoside analogue 5-ethynyl-2´-deoxyuridine (EdU) into newly synthesized DNA. The distinct cell-cycle perturbations and cell-kill potential of compound 1 are discussed in the light of the DNA interactions of this agent and its potential to overcome cisplatin resistance in NSCLC.

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