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1.
SLAS Discov ; 23(7): 742-750, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29873570

RESUMO

Enhancing antitumor activities of the human immune system is a clinically proven approach with the advent of monoclonal antibodies recognizing programmed cell death protein-1 (PD1) receptors on immune cell surfaces. Historically, using flow cytometry as a means to assess next-generation agent activities was underused, largely due to limits on cell number and assay sensitivity. Here, we leveraged an IntelliCyt high-throughput flow cytometry platform to monitor human dendritic cell maturation and lymphocyte proliferation in mixed lymphocyte reactions. Specifically, we established flow cytometry-based immunophenotyping and screening methodologies capable of measuring T-cell activation as a result of cell-associated antigens presented on dendritic cell surfaces, as indicated by cell proliferation, cytokine secretion, and surface marker expression. Together, the overall novelty of this 384-well platform is its capability to measure multiple functional readouts in one well and consistently evaluate large numbers of compounds in a single study, as well as its ability to show increased assay sensitivity requiring considerably fewer primary cells and less reagents compared to more traditional 96-well flow cytometry methods.


Assuntos
Células Dendríticas/metabolismo , Citometria de Fluxo , Ensaios de Triagem em Larga Escala , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Linfócitos T/metabolismo , Citocinas/metabolismo , Células Dendríticas/imunologia , Citometria de Fluxo/métodos , Humanos , Ativação Linfocitária/imunologia , Linfócitos T/imunologia
2.
J Biomol Screen ; 21(8): 866-74, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27142718

RESUMO

Oral agents targeting Janus-associated kinases (JAKs) are promising new agents in clinical development. To better understand the relationship between JAK inhibition and biological outcome, compounds targeting JAKs were evaluated in peripheral human whole blood. To date, these analyses are low throughput and costly. Here, we developed a robust 384-well, high-throughput flow-based assay approach to screen small molecules for JAK/STAT signaling inhibition in human whole blood. This assay platform provides a highly sensitive analysis of signaling events in blood and facilitates measurement of target engagement. Further, the automation technologies and process optimizations developed here overcame sample integrity, handling, and multiparametric data analysis bottlenecks without affecting assay performance. Together these efforts dramatically increased sample throughput compared to conventional manual flow cytometric approaches and enabled development of novel JAK/STAT inhibitors.


Assuntos
Citometria de Fluxo/métodos , Ensaios de Triagem em Larga Escala/métodos , Inibidores de Proteínas Quinases/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Humanos , Janus Quinases/antagonistas & inibidores , Janus Quinases/genética , Fosforilação , Inibidores de Proteínas Quinases/química , Fatores de Transcrição STAT/antagonistas & inibidores , Fatores de Transcrição STAT/genética , Bibliotecas de Moléculas Pequenas/química
3.
Exp Cell Res ; 338(2): 251-60, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26302264

RESUMO

Cellular levels of inhibitor of apoptosis (IAP) proteins are elevated in multiple human cancers and their activities often play a part in promoting cancer cell survival by blocking apoptotic pathways, controlling signal transduction pathways and contributing to resistance. These proteins function through interactions of their BIR (baculoviral IAP repeat) protein domains with pathway components and these interactions are endogenously antagonized by Smac/Diablo (second mitochondrial activator of caspases/direct IAP binding protein with low isoelectric point). This report describes development of synthetic smac mimetics (SM) and compares their binding, antiproliferative and anti-tumor activities. All dimeric antagonists inhibit in vitro smac tetrapeptide binding to recombinant IAP proteins, rescue IAP-bound caspase-3 activity and show anti-proliferative activity against human A875 melanoma cells. One heterodimeric SM, SM3, binds tightly to IAP proteins in vitro and slowly dissociates (greater than two hours) from these protein complexes compared to the other antagonists. In addition, in vitro SM anti-proliferation potency is influenced by ABCB1 transporter (ATP-binding cassette, sub-family B; MDR1, P-gp) activities and one antagonist, SM5, does not appear to be an ABCB1 efflux pump substrate. All dimeric smac mimetics inhibit the growth of human melanoma A875 tumors implanted in athymic mice at well-tolerated doses. One antagonist, SM4, shows broad spectrum in vivo anti-tumor activity and modulates known pharmacodynamic markers of IAP antagonism. These data taken together demonstrate the range of diverse dimeric IAP antagonist activities and supports their potential as anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Transporte Biológico/efeitos dos fármacos , Caspase 3/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Proteínas Mitocondriais/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Biomimética/métodos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Células HCT116 , Humanos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína/efeitos dos fármacos
4.
ACS Med Chem Lett ; 6(7): 770-5, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26191364

RESUMO

A series of dimeric macrocyclic compounds were prepared and evaluated as antagonists for inhibitor of apoptosis proteins. The most potent analogue 11, which binds to XIAP and c-IAP proteins with high affinity and induces caspase-3 activation and ultimately cell apoptosis, inhibits growth of human melanoma and colorectal cell lines at low nanomolar concentrations. Furthermore, compound 11 demonstrated significant antitumor activity in the A875 human melanoma xenograft model at doses as low as 2 mg/kg on a q3d schedule.

5.
J Med Chem ; 58(6): 2855-61, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25695766

RESUMO

Affinity selection screening of macrocycle libraries derived from DNA-programmed chemistry identified XIAP BIR2 and BIR3 domain inhibitors that displace bound pro-apoptotic caspases. X-ray cocrystal structures of key compounds with XIAP BIR2 suggested potency-enhancing structural modifications. Optimization of dimeric macrocycles with similar affinity for both domains were potent pro-apoptotic agents in cancer cell lines and efficacious in shrinking tumors in a mouse xenograft model.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Compostos Macrocíclicos/química , Compostos Macrocíclicos/uso terapêutico , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores , Animais , Antineoplásicos/farmacocinética , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Cristalografia por Raios X , Descoberta de Drogas , Feminino , Biblioteca Gênica , Humanos , Compostos Macrocíclicos/farmacocinética , Camundongos , Modelos Moleculares , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
6.
J Med Chem ; 58(3): 1556-62, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25584393

RESUMO

The prominent role of IAPs in controlling cell death and their overexpression in a variety of cancers has prompted the development of IAP antagonists as potential antitumor therapies. We describe the identification of a series of heterodimeric antagonists with highly potent antiproliferative activities in cIAP- and XIAP-dependent cell lines. Compounds 15 and 17 further demonstrate curative efficacy in human melanoma and lung cancer xenograft models and are promising candidates for advanced studies.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Neoplasias Experimentais/tratamento farmacológico , Prolina/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estrutura Molecular , Neoplasias Experimentais/patologia , Prolina/síntese química , Prolina/química , Relação Estrutura-Atividade
7.
Exp Cell Res ; 332(2): 267-77, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25486070

RESUMO

Cancer cell survival is frequently dependent on the elevated levels of members of the Bcl-2 family of prosurvival proteins that bind to and inactivate BH3-domain pro-apoptotic cellular proteins. Small molecules that inhibit the protein-protein interactions between prosurvival and proapoptotic Bcl-2 family members (so-called "BH3 mimetics") have a potential therapeutic value, as indicated by clinical findings obtained with ABT-263 (navitoclax), a Bcl-2/Bcl-xL antagonist, and more recently with GDC-0199/ABT-199, a more selective antagonist of Bcl-2. Here, we report study results of the functional role of the prosurvival protein Mcl-1 against a panel of solid cancer cell lines representative of different tumor types. We observed silencing of Mcl-1 expression by small interfering RNAs (siRNAs) significantly reduced viability and induced apoptosis in almost 30% of cell lines tested, including lung and breast adenocarcinoma, as well as glioblastoma derived lines. Most importantly, we provide a mechanistic basis for this sensitivity by showing antagonism of Mcl-1 function with specific BH3 peptides against isolated mitochondria induces Bak oligomerization and cytochrome c release, therefore demonstrating that mitochondria from Mcl-1-sensitive cells depend on Mcl-1 for their integrity and that antagonizing Mcl-1 function is sufficient to induce apoptosis. Thus, our results lend further support for considering Mcl-1 as a therapeutic target in a number of solid cancers and support the rationale for development of small molecule BH3-mimetics antagonists of this protein.


Assuntos
Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética
8.
Bioorg Med Chem Lett ; 22(12): 3951-6, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22608393

RESUMO

5-Butyl-1,4-diphenyl pyrazole and 2-amino-5-chloro pyrimidine acylsulfonamides were developed as potent dual antagonists of Bcl-2 and Bcl-xL. Compounds were optimized for binding to the I88, L92, I95, and F99 pockets normally occupied by pro-apoptotic protein Bim. An X-ray crystal structure confirmed the proposed binding mode. Observation of cytochrome c release from isolated mitochondria in MV-411 cells provides further evidence of target inhibition. Compounds demonstrated submicromolar antiproliferative activity in Bcl-2/Bcl-xL dependent cell lines.


Assuntos
Antineoplásicos/síntese química , Pirazóis/síntese química , Pirimidinas/síntese química , Sulfonamidas/síntese química , Proteína X Associada a bcl-2/antagonistas & inibidores , Proteína bcl-X/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Citocromos c/metabolismo , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Moleculares , Ligação Proteica , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Pirazóis/farmacologia , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Proteína X Associada a bcl-2/química , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/química , Proteína bcl-X/metabolismo
9.
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