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1.
MAbs ; 11(6): 1012-1024, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242061

RESUMO

T cell redirection mediated by bispecific antibodies (BsAbs) is a promising cancer therapy. Dual antigen binding is necessary for potent T cell redirection and is influenced by the structural characteristics of a BsAb, which are dependent on its IgG subclass. In this study, model BsAbs targeting CD19xCD3 were generated in variants of IgG1, IgG2, and IgG4 carrying Fc mutations that reduce FcγR interaction, and two chimeric IgG subclasses termed IgG1:2 and IgG4:2, in which the IgG1- or IgG4-F(ab)2 are grafted on an IgG2 Fc. Molecules containing an IgG2 or IgG4-F(ab)2 domain were confirmed to be the most structurally compact molecules. All BsAbs were shown to bind both of their target proteins (and corresponding cells) equally well. However, CD19xCD3 IgG2 did not bind both antigens simultaneously as measured by the absence of cellular clustering of T cells with target cells. This translated to a reduced potency of IgG2 BsAbs in T-cell redirection assays. The activity of IgG2 BsAbs was fully restored in the chimeric subclasses IgG4:2 and IgG1:2. This confirmed the major contribution of the F(ab)2 region to the BsAb's functional activity and demonstrated that function of BsAbs can be modulated by engineering molecules combining different Fc and F(ab)2 domains. Abbreviations: ADCC: Antibody-dependent cellular cytotoxicity; AlphaScreenTM: Amplified Luminescent Proximity Homogeneous Assay Screening; ANOVA: Analysis of variance; BiTE: bispecific T-cell engager; BSA: bovine serum albumin; BsAb: bispecific antibody; cFAE: controlled Fab-arm exchange; CDC: complement-dependent cellular cytotoxicity; CIEX: cation-exchange; CIR: chimeric immune receptor; DPBS: Dulbecco's phosphate-buffered saline; EC50 value: effective concentration to reach half-maximum effect; EGFR: epidermal growth factor receptor; EI: expansion index (RAt=x/RAt=0); FACS: fluorescence-activated cell sorting; FVD: fixable viability dye; HI-HPLC: hydrophobic interaction HPLC; HI-FBS: heat-inactivated fetal bovine serum; HPLC: high-pressure liquid chromatography; IC50 value: effective concentration to reach half-maximum inhibition; IQ: Inhibition Quotient; IS: immunological synapse; MES: 2-(N-morpholino)ethanesulfonic acid; R-PE: recombinant phycoerythrin; RA: red area in µm2/well; RD: receptor density; RFP: red fluorescent protein; Rg: radius of gyration; RSV: respiratory syncytial virus; SAXS: small-angle x-ray scattering; scFv: single-chain variable fragment; SD: standard deviation; SPR: surface plasmon resonance; WT: wild-type.

2.
Cancer Cell ; 34(4): 674-689.e8, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30245083

RESUMO

Intra-tumor heterogeneity caused by clonal evolution is a major problem in cancer treatment. To address this problem, we performed label-free quantitative proteomics on primary acute myeloid leukemia (AML) samples. We identified 50 leukemia-enriched plasma membrane proteins enabling the prospective isolation of genetically distinct subclones from individual AML patients. Subclones differed in their regulatory phenotype, drug sensitivity, growth, and engraftment behavior, as determined by RNA sequencing, DNase I hypersensitive site mapping, transcription factor occupancy analysis, in vitro culture, and xenograft transplantation. Finally, we show that these markers can be used to identify and longitudinally track distinct leukemic clones in patients in routine diagnostics. Our study describes a strategy for a major improvement in stratifying cancer diagnosis and treatment.

4.
Cancer Res ; 76(13): 3942-53, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27216193

RESUMO

Non-small cell lung cancers (NSCLC) with activating EGFR mutations become resistant to tyrosine kinase inhibitors (TKI), often through second-site mutations in EGFR (T790M) and/or activation of the cMet pathway. We engineered a bispecific EGFR-cMet antibody (JNJ-61186372) with multiple mechanisms of action to inhibit primary/secondary EGFR mutations and the cMet pathway. JNJ-61186372 blocked ligand-induced phosphorylation of EGFR and cMet and inhibited phospho-ERK and phospho-AKT more potently than the combination of single receptor-binding antibodies. In NSCLC tumor models driven by EGFR and/or cMet, JNJ-61186372 treatment resulted in tumor regression through inhibition of signaling/receptor downmodulation and Fc-driven effector interactions. Complete and durable regression of human lung xenograft tumors was observed with the combination of JNJ-61186372 and a third-generation EGFR TKI. Interestingly, treatment of cynomolgus monkeys with JNJ-61186372 resulted in no major toxicities, including absence of skin rash observed with other EGFR-directed agents. These results highlight the differentiated potential of JNJ-61186372 to inhibit the spectrum of mutations driving EGFR TKI resistance in NSCLC. Cancer Res; 76(13); 3942-53. ©2016 AACR.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Macaca fascicularis , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação/genética , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Prostate ; 71(5): 480-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20878947

RESUMO

BACKGROUND: Androgen receptor (AR) antagonists are part of the standard of care for prostate cancer. Despite the almost inevitable development of resistance in prostate tumors to AR antagonists, no new AR antagonists have been approved for over a decade. Treatment failure is due in part to mutations that increase activity of AR in response to lower ligand concentrations as well as to mutations that result in AR response to a broader range of ligands. The failure to discover new AR antagonists has occurred in the face of continued research; to enable progress, a clear understanding of the reasons for failure is required. METHODS: Non-clinical drug safety studies and safety pharmacology assays were performed on previously approved AR antagonists (bicalutamide, flutamide, nilutamide), next generation antagonists in clinical testing (MDV3100, BMS-641988), and a pre-clinical drug candidate (BMS-501949). In addition, non-clinical studies with AR mutant mice, and EEG recordings in rats were performed. Non-clinical findings are compared to disclosures of clinical trial results. RESULTS: As a drug class, AR antagonists cause seizure in animals by an off-target mechanism and are found in vitro to inhibit GABA-A currents. Clinical trials of candidate next generation AR antagonists identify seizure as a clinical safety risk. CONCLUSIONS: Non-clinical drug safety profiles of the AR antagonist drug class create a significant barrier to the identification of next generation AR antagonists. GABA-A inhibition is a common off-target activity of approved and next generation AR antagonists potentially explaining some side effects and safety hazards of this class of drugs.


Assuntos
Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/toxicidade , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios/farmacocinética , Animais , Cães , Descoberta de Drogas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neoplasias da Próstata/metabolismo , Ratos , Ratos Sprague-Dawley
6.
Endocrinology ; 151(9): 4123-32, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20610571

RESUMO

The biology of IGF-IR/IR signaling was studied in normal mouse embryonic fibroblasts (MEFs) that were either wild type (wt), heterozygous (het), or null for the IGF-IR. The ability of IGF-I, IGF-II, or insulin to stimulate serum-starved MEFs was characterized by gene expression profiling and biochemical analyses for activation of downstream signals. Each genotypic group of MEFs exhibited distinct patterns of expression both while resting and in response to stimulation. The insulin receptor (IR) pathway in IGF-IR null MEFs was hypersensitive to insulin ligand stimulation resulting in greater AKT phosphorylation than in wt or het MEFs stimulated with the same ligand. Interestingly, the IR pathway hypersensitivity in IGF-IR null MEFs occurred with no observed changes in the levels of IR isoforms A or B. A new small molecule IGF-IR inhibitor (BMS-754807), having equipotent activity against both IGF-IR and IR, proved effective in suppressing both AKT and ERK phosphorylation from both the IGF-IR and IR pathways by all three ligands tested in wt, het, and null MEFs. The use of a dual IGF-IR/IR inhibitor addresses concerns about the use of growth inhibiting therapies directed against the IGF-IR receptor in certain cancers. Lastly, comparison of the antiproliferative effects (IC(50)s) of various compounds in wt vs. null MEFs demonstrates that genetically characterized MEFs provide a simple and inexpensive tool with which to define compounds as having mostly on-target or off-target IGF-IR activities because off-target compounds affect both wt and null MEFs equally.


Assuntos
Proliferação de Células/efeitos dos fármacos , Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Triazinas/farmacologia , Animais , Western Blotting , Células Cultivadas , Análise por Conglomerados , Embrião de Mamíferos/citologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Bioorg Med Chem Lett ; 20(5): 1744-8, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20153189
9.
Mol Cancer Ther ; 8(12): 3341-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19996272

RESUMO

BMS-754807 is a potent and reversible inhibitor of the insulin-like growth factor 1 receptor/insulin receptor family kinases (Ki, <2 nmol/L). It is currently in phase I development for the treatment of a variety of human cancers. BMS-754807 effectively inhibits the growth of a broad range of human tumor types in vitro, including mesenchymal (Ewing's, rhabdomyosarcoma, neuroblastoma, and liposarcoma), epithelial (breast, lung, pancreatic, colon, gastric), and hematopoietic (multiple myeloma and leukemia) tumor cell lines (IC50, 5-365 nmol/L); the compound caused apoptosis in a human rhabdomyosarcoma cell line, Rh41, as shown by an accumulation of the sub-G1 fraction, as well as by an increase in poly ADP ribose polymerase and Caspase 3 cleavage. BMS-754807 is active in vivo in multiple (epithelial, mesenchymal, and hematopoietic) xenograft tumor models with tumor growth inhibition ranging from 53% to 115% and at a minimum effective dose of as low as 6.25 mg/kg dosed orally daily. Combination studies with BMS-754807 have been done on multiple human tumor cell types and showed in vitro synergies (combination index, <1.0) when combined with cytotoxic, hormonal, and targeted agents. The combination of cetuximab and BMS-754807 in vivo, at multiple dose levels, resulted in improved clinical outcome over single agent treatment. These data show that BMS-754807 is an efficacious, orally active growth factor 1 receptor/insulin receptor family-targeted kinase inhibitor that may act in combination with a wide array of established anticancer agents.


Assuntos
Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Triazinas/farmacologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Western Blotting , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cetuximab , Relação Dose-Resposta a Droga , Teste de Tolerância a Glucose , Humanos , Concentração Inibidora 50 , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Pirazóis/administração & dosagem , Pirazóis/farmacocinética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Triazinas/administração & dosagem , Triazinas/farmacocinética , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Cancer Res ; 69(16): 6522-30, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19654297

RESUMO

Despite an excellent initial response to first-line hormonal treatment, most patients with metastatic prostate cancer will succumb to a hormone-refractory form of the disease. Because these tumors are still dependent on a functional androgen receptor (AR), there is a need to find novel and more potent antiandrogens. While searching for small molecules that bind to the AR and inhibit its transcriptional activity, BMS-641988 was discovered. This novel antiandrogen showed an increased (>1 log) potency compared with the standard antiandrogen, bicalutamide, in both binding affinity to the AR and inhibition of AR-mediated transactivation in cell-based reporter assays. In mature rats, BMS-641988 strongly inhibited androgen-dependent growth of the ventral prostate and seminal vesicles. In the CWR-22-BMSLD1 human prostate cancer xenograft model, BMS-641988 showed increased efficacy over bicalutamide (average percent tumor growth inhibition >90% versus <50%), even at exposure levels of bicalutamide 3-fold greater than what can be attained in humans. Furthermore, BMS-641988 was efficacious in CWR-22-BMSLD1 tumors initially refractory to treatment with bicalutamide. BMS-641988 was highly efficacious in the LuCaP 23.1 human prostate xenograft model, inducing stasis throughout the approximately 30-day dosing. To explore the functional mechanisms of BMS-641988, gene expression profiling analysis was done on CWR-22-BMSLD1 xenograft models in mice. Treatment with BMS-641988 resulted in a global gene expression profile more similar to castration compared with that of bicalutamide. Overall, these data highlight that the unique preclinical profile of BMS-641988 may provide additional understanding for the hormonal treatment of prostate cancer.


Assuntos
Antagonistas de Receptores de Andrógenos , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Imidas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Animais , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Descoberta de Drogas , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Imidas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Clin Cancer Res ; 15(10): 3251-5, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19447877

RESUMO

The understanding of the key role that androgens play on the normal and pathological physiology of the prostate guided the development of different therapies for the treatment of locally advanced or metastatic prostate cancer (PCa). These so-called androgen deprivation therapies include surgical or chemical castration, achieved by the administration of gonadotropin-releasing hormone analogs; inhibition of steroidogenic enzymes; and finally, blocking of the binding of androgens to their receptor (AR) by the use of antiandrogens. Despite an excellent initial response, in approximately 2 to 3 years, most of these patients will succumb to the castration resistant form of the disease. Remarkably, even in the presence of castration levels of circulating androgens, these tumors are still dependent on a functional AR, and several molecular mechanisms have been proposed to explain this phenomenon. These include: (1) gene amplification and increased expression of the AR mRNA and protein, (2) selection of mutations in the AR that confer broader ligand specificity, (3) changes in the ratios or expression between the AR and its coregulators, (4) increased expression of steroidogenic enzymes, and (5) up-regulation of cross-talk signal transduction pathways that can activate the AR in a ligand-independent manner. We will summarize how these molecular hypotheses are being tested in the clinic by the latest therapeutic modalities.


Assuntos
Androgênios/metabolismo , Orquiectomia , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Modelos Biológicos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Transdução de Sinais/efeitos dos fármacos
12.
Cancer Res ; 69(1): 161-70, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19117999

RESUMO

Overexpression and enhanced activity of insulin-like growth factor-I receptor (IGF-IR) in diverse tumor types make it an attractive target for cancer therapy. BMS-536924 is a potent small molecule inhibitor of IGF-IR, which shows antitumor activity in multiple tumor models, including sarcoma. To facilitate the development of IGF-IR inhibitors as cancer therapy, identification of biomarkers for selecting patients most likely to derive clinical benefit is needed. To do so, 28 sarcoma and neuroblastoma cell lines were screened for in vitro response to BMS-536924 to identify sensitive and resistant cell lines. Notably, Ewing's sarcoma, rhabdomyosarcoma, and neuroblastoma are more responsive to BMS-536924, suggesting these specific subtypes may represent potential targeted patient subpopulations for the IGF-IR inhibitor. Gene expression and protein profiling were performed on these cell lines, and candidate biomarkers correlating with intrinsic and/or acquired resistance to BMS-536924 were identified. IGF-I, IGF-II, and IGF-IR were highly expressed in sensitive cell lines, whereas IGFBP-3 and IGFBP-6 were highly expressed in resistant lines. Overexpression of epidermal growth factor receptor (EGFR) and its ligands in resistant cell lines may represent one possible resistance mechanism by the adaptation of IGF-IR-independent growth using alternative signaling pathways. Based on cross-talk between IGF-IR and EGFR pathways, combination studies to target both pathways were performed, and enhanced inhibitory activities were observed. These results provide a strategy for testing combinations of IGF-IR inhibitors with other targeted therapies in clinical studies to achieve improved patient outcomes. Further exploration of mechanisms for intrinsic and acquired drug resistance by these preclinical studies may lead to more rationally designed drugs that target multiple pathways for enhanced antitumor efficacy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzimidazóis/farmacologia , Receptores ErbB/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Piridonas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Receptor IGF Tipo 1/antagonistas & inibidores , Sarcoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Receptores ErbB/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Receptor ErbB-2/metabolismo , Sarcoma/genética , Sarcoma/metabolismo , Sarcoma/patologia
13.
Clin Cancer Res ; 15(1): 226-37, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19118050

RESUMO

PURPOSE: This study aimed to test the ability of a new insulin-like growth factor receptor (IGF-IR) tyrosine kinase inhibitor, BMS-536924, to reverse the ability of constitutively active IGF-IR (CD8-IGF-IR) to transform MCF10A cells, and to examine the effect of the inhibitor on a range of human breast cancer cell lines. EXPERIMENTAL DESIGN: CD8-IGF-IR-MCF10A cells were grown in monolayer culture, three-dimensional (3D) culture, and as xenografts, and treated with BMS-536924. Proliferation, cell cycle, polarity, and apoptosis were measured. Twenty-three human breast cancer cell lines were treated in monolayer culture with BMS-536924, and cell viability was measured. MCF7, MDA-MB-231, and MDA-MB-435 were treated with BMS-536924 in monolayer and 3D culture, and proliferation, migration, polarity, and apoptosis were measured. RESULTS: Treatment of CD8-IGF-IR-MCF10A cells grown in 3D culture with BMS-536924 caused a blockade of proliferation, restoration of apical-basal polarity, and enhanced apoptosis, resulting in a partial phenotypic reversion to normal acini. In monolayer culture, BMS-536924 induced a dose-dependent inhibition of proliferation, with an accumulation of cells in G(0)/G(1,), and completely blocked CD8-IGF-IR-induced migration, invasion, and anchorage-independent growth. CD8-IGF-IR-MCF10A xenografts treated with BMS-536924 (100 mg/kg/day) showed a 76% reduction in xenograft volume. In a series of 23 human breast cancer cell lines, BMS-536924 inhibited monolayer proliferation of 16 cell lines. Most strikingly, treatment of MCF7 cells grown in 3D culture with BMS-536924 caused blockade of proliferation, and resulted in the formation of hollow polarized lumen. CONCLUSIONS: These results show that the new small molecule BMS-536924 is an effective inhibitor of IGF-IR, causing a reversion of an IGF-IR - mediated transformed phenotype.


Assuntos
Benzimidazóis/farmacologia , Neoplasias da Mama/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Glândulas Mamárias Humanas/efeitos dos fármacos , Piridonas/farmacologia , Receptores de Somatomedina/antagonistas & inibidores , Apoptose , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Receptores de Somatomedina/metabolismo
14.
Mol Cancer Ther ; 7(11): 3490-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19001433

RESUMO

In developing inhibitors of the LIM kinases, the initial lead molecules combined potent target inhibition with potent cytotoxic activity. However, as subsequent compounds were evaluated, the cytotoxic activity separated from inhibition of LIM kinases. A rapid determination of the cytotoxic mechanism and its molecular target was enabled by integrating data from two robust core technologies. High-content assays and gene expression profiling both indicated an effect on microtubule stability. Although the cytotoxic compounds are still kinase inhibitors, and their structures did not predict tubulin as an obvious target, these results provided the impetus to test their effects on microtubule polymerization directly. Unexpectedly, we confirmed tubulin itself as a molecular target of the cytotoxic kinase inhibitor compounds. This general approach to mechanism of action questions could be extended to larger data sets of quantified phenotypic and gene expression data.


Assuntos
Antineoplásicos/química , Antineoplásicos/toxicidade , Quinases Lim/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Perfilação da Expressão Gênica , Humanos , Quinases Lim/metabolismo , Microscopia de Fluorescência , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
15.
Mol Cancer Ther ; 7(9): 2589-98, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18765823

RESUMO

We have reported previously the activity of the insulin-like growth factor-I (IGF-IR)/insulin receptor (InsR) inhibitor, BMS-554417, in breast and ovarian cancer cell lines. Further studies indicated treatment of OV202 ovarian cancer cells with BMS-554417 increased phosphorylation of HER-2. In addition, treatment with the pan-HER inhibitor, BMS-599626, resulted in increased phosphorylation of IGF-IR, suggesting a reciprocal cross-talk mechanism. In a panel of five ovarian cancer cell lines, simultaneous treatment with the IGF-IR/InsR inhibitor, BMS-536924 and BMS-599626, resulted in a synergistic antiproliferative effect. Furthermore, combination therapy decreased AKT and extracellular signal-regulated kinase activation and increased biochemical and nuclear morphologic changes consistent with apoptosis compared with either agent alone. In response to treatment with BMS-536924, increased expression and activation of various members of the HER family of receptors were seen in all five ovarian cancer cell lines, suggesting that inhibition of IGF-IR/InsR results in adaptive up-regulation of the HER pathway. Using MCF-7 breast cancer cell variants that overexpressed HER-1 or HER-2, we then tested the hypothesis that HER receptor expression is sufficient to confer resistance to IGF-IR-targeted therapy. In the presence of activating ligands epidermal growth factor or heregulin, respectively, MCF-7 cells expressing HER-1 or HER-2 were resistant to BMS-536924 as determined in a proliferation and clonogenic assay. These data suggested that simultaneous treatment with inhibitors of the IGF-I and HER family of receptors may be an effective strategy for clinical investigations of IGF-IR inhibitors in breast and ovarian cancer and that targeting HER-1 and HER-2 may overcome clinical resistance to IGF-IR inhibitors.


Assuntos
Benzimidazóis/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Piridonas/farmacologia , Receptor ErbB-2/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Cross-Talk/efeitos dos fármacos , Receptor ErbB-2/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores
17.
Bioorg Med Chem Lett ; 18(6): 1910-5, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18291644

RESUMO

A novel series of [2.2.1]-oxabicyclo imide-based compounds were identified as potent antagonists of the androgen receptor. Molecular modeling and iterative drug design were applied to optimize this series. The lead compound [3aS-(3aalpha,4beta,5beta,7beta,7aalpha)]-4-(octahydro-5-hydroxy-4,7-dimethyl-1,3-dioxo-4,7-epoxy-2H-isoindol-2-yl)-2-iodobenzonitrile was shown to have potent in vivo efficacy after oral dosing in the CWR22 human prostate tumor xenograph model.


Assuntos
Antagonistas de Receptores de Andrógenos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Isoindóis/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Administração Oral , Antagonistas de Androgênios/farmacologia , Anilidas/farmacologia , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Cromatografia Líquida de Alta Pressão , Desenho de Drogas , Humanos , Isoindóis/síntese química , Isoindóis/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Nitrilos/farmacologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Ligação Proteica , Receptores Androgênicos/metabolismo , Relação Estrutura-Atividade , Compostos de Tosil/farmacologia , Células Tumorais Cultivadas
18.
Prostate ; 68(6): 629-39, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18213636

RESUMO

Prostate cancer continues to be a major cause of morbidity and mortality in men around the world. The field of prostate cancer research continues to be hindered by the lack of relevant preclinical models to study tumorigenesis and to further development of effective prevention and therapeutic strategies. The Prostate Cancer Foundation held a Prostate Cancer Models Working Group (PCMWG) Summit on August 6th and 7th, 2007 to address these issues. The PCMWG reviewed the state of prostate cancer preclinical models and identified the current limitations of cell line, xenograft and genetically engineered mouse models that have hampered the transition of scientific findings from these models to human clinical trials. In addition the PCMWG identified administrative issues that inhibit the exchange of models and impede greater interactions between academic centers and these centers with industry. The PCMWG identified potential solutions for discovery bottlenecks that include: (1) insufficient number of models with insufficient molecular and biologic diversity to reflect human cancer, (2) a lack of understanding of the molecular events that define tumorigenesis, (3) a lack of tools for studying tumor-host interactions, (4) difficulty in accessing model systems across institutions, and (5) addressing why preclinical studies appear not to be predictive of human clinical trials. It should be possible to apply the knowledge gained molecular and epigenetic studies to develop new cell lines and models that mimic progressive and fatal prostate cancer and ultimately improve interventions.


Assuntos
Modelos Animais de Doenças , Neoplasias Experimentais/patologia , Neoplasias da Próstata/patologia , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias Experimentais/etiologia , Neoplasias Experimentais/prevenção & controle , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/prevenção & controle
19.
BMC Cell Biol ; 9: 4, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18218096

RESUMO

BACKGROUND: A crucial event in Prostate Cancer progression is the conversion from a hormone-sensitive to a hormone-refractory disease state. Correlating with this transition, androgen receptor (AR) amplification and mutations are often observed in patients failing hormonal ablation therapies. beta-Catenin, an essential component of the canonical Wnt signaling pathway, was shown to be a coactivator of the AR signaling in the presence of androgens. However, it is not yet clear what effect the increased levels of the AR could have on the Wnt signaling pathway in these hormone-refractory prostate cells. RESULTS: Transient transfections of several human prostate cancer cell lines with the AR and multiple components of the Wnt signaling pathway demonstrate that the AR overexpression can potentiate the transcriptional activities of Wnt/beta-Catenin signaling. In addition, the simultaneous activation of the Wnt signaling pathway and overexpression of the AR promote prostate cancer cell growth and transformation at castration levels of androgens. Interestingly, the presence of physiological levels of androgen or other AR agonists inhibits these effects. These observations are consistent with the nuclear co-localization of the AR and beta-Catenin shown by immunohistochemistry in human prostate cancer samples. Furthermore, chromatin immunoprecipitation assays showed that Wnt3A can recruit the AR to the promoter regions of Myc and Cyclin D1, which are well-characterized downstream targets of the Wnt signalling pathway. The same assays demonstrated that the AR and beta-Catenin can be recruited to the promoter and enhancer regions of a known AR target gene PSA upon Wnt signaling. These results suggest that the AR is promoting Wnt signaling at the chromatin level. CONCLUSION: Our findings suggest that the AR signaling through the Wnt/beta-Catenin pathway should be added to the well established functional interactions between both pathways. Moreover, our data show that via this interaction the AR could promote prostate cell malignancy in a ligand-independent manner.


Assuntos
Androgênios/biossíntese , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais , beta Catenina/metabolismo , Androgênios/genética , Núcleo Celular/metabolismo , Transformação Celular Neoplásica , Cromatina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Humanos , Masculino , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Ativação Transcricional , Transfecção , Proteínas Wnt/agonistas , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/agonistas , beta Catenina/genética
20.
Mol Cell Biol ; 27(8): 3165-75, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17296734

RESUMO

Type I insulin-like growth factor receptor (IGF-IR) can transform mouse fibroblasts; however, little is known about the transforming potential of IGF-IR in human fibroblasts or epithelial cells. We found that overexpression of a constitutively activated IGF-IR (CD8-IGF-IR) was sufficient to cause transformation of immortalized human mammary epithelial cells and growth in immunocompromised mice. Furthermore, CD8-IGF-IR caused cells to undergo an epithelial-to-mesenchymal transition (EMT) which was associated with dramatically increased migration and invasion. The EMT was mediated by the induction of the transcriptional repressor Snail and downregulation of E-cadherin. NF-kappaB was highly active in CD8-IGF-IR-MCF10A cells, and both increased levels of Snail and the EMT were partially reversed by blocking NF-kappaB or IGF-IR activity. This study places IGF-IR among a small group of oncogenes that, when overexpressed alone, can confer in vivo tumorigenic growth of MCF10A cells and indicates the hierarchy in the mechanism of IGF-IR-induced EMT.


Assuntos
Transformação Celular Neoplásica , Células Epiteliais/citologia , Glândulas Mamárias Humanas/citologia , Mesoderma/citologia , NF-kappa B/metabolismo , Receptor IGF Tipo 1/metabolismo , Fatores de Transcrição/metabolismo , Animais , Benzimidazóis/farmacologia , Antígenos CD8/metabolismo , Caderinas/genética , Transformação Celular Neoplásica/efeitos dos fármacos , Colágeno/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Combinação de Medicamentos , Células Epiteliais/efeitos dos fármacos , Genes Reguladores , Humanos , Laminina/efeitos dos fármacos , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/crescimento & desenvolvimento , Camundongos , Modelos Biológicos , Morfogênese/efeitos dos fármacos , Proteoglicanas/efeitos dos fármacos , Piridonas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição da Família Snail , Transplante Heterólogo
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