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1.
Mol Cancer Ther ; 14(2): 620-30, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25527633

RESUMO

Insulin-like growth factor receptor 1 (IGF-1R)-targeting therapies are currently at an important crossroad given the low clinical response rates seen in unselected patients. Predictive biomarkers for patient selection are critical for improving clinical benefit. Coupling in vitro sensitivity testing of BMS-754807, a dual IGF-1R/IR inhibitor, with genomic interrogations in 60 human colorectal cancer cell lines, we identified biomarkers correlated with response to BMS-754807. The results showed that cell lines with BRAF(V600E) or KRAS(G13D) mutation were resistant, whereas cell lines with wild-type of both KRAS and BRAF were particularly sensitive to BMS-754807 if they have either higher RNA expression levels of IR-A or lower levels of IGFBP6. In addition, the cell lines with KRAS mutations, those with either insulin receptor substrate 2 (IRS2) copy number gain (CNG) or higher IGF-1R expression levels, were more sensitive to the drug. Furthermore, cell lines with IRS2 CNG had higher levels of ligand-stimulated activation of IGF-1R and AKT, suggesting that these cell lines with IGF-IR signaling pathways more actively coupled to AKT signaling are more responsive to IGF-1R/IR inhibition. IRS2 siRNA knockdown reduced IRS2 protein expression levels and decreased sensitivity to BMS-754807, providing evidence for the functional involvement of IRS2 in mediating the drug response. The prevalence of IRS2 CNG in colorectal cancer tumors as measured by qPCR-CNV is approximately 35%. In summary, we identified IRS2 CNG, IGF-1R, IR-A, and IGFBP6 RNA expression levels, and KRAS and BRAF mutational status as candidate predictive biomarkers for response to BMS-754807. This work proposed clinical development opportunities for BMS-754807 in colorectal cancer with patient selection to improve clinical benefit.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Dosagem de Genes , Proteínas Substratos do Receptor de Insulina/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Pirazóis/farmacologia , Triazinas/farmacologia , Proteínas ras/genética , Western Blotting , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA/genética , Análise Mutacional de DNA , Amplificação de Genes/efeitos dos fármacos , Humanos , Proteína 6 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Ligantes , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras) , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores
2.
Exp Hematol ; 40(9): 715-723.e6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22613471

RESUMO

Malignant transformation of normal hematopoietic progenitors is a multistep process that likely requires interaction between collaborating oncogenic signals at critical junctures. For instance, the MLL-AF9 fusion oncogene is thought to contribute to myeloid leukemogenesis by driving a hematopoietic stem cell-like "self-renewal" gene expression signature in committed myeloid progenitors. In addition, insulin-like growth factor (IGF) signaling has been implicated in self-renewal/pluripotency in hematopoietic and embryonic stem cell contexts and supports cell growth/survival by activation of downstream pathways, including phosphatidylinositol 3-kinase/Akt and Ras/Raf/extracellular signal-regulated kinase. We hypothesized that IGF signaling could be an important contributor in the process of cellular transformation and/or clonal propagation. Utilizing an MLL-AF9 mouse bone marrow transplantation model of acute myelogenous leukemia, we discovered that committed myeloid progenitor cells with genetically reduced levels of IGF1R were less susceptible to leukemogenic transformation due, at least in part, to a cell-autonomous defect in clonogenic activity. Rather unexpectedly, genetic deletion of IGF1R by inducible Cre recombinase had no effect on growth/survival of established leukemia cells. These findings suggest that IGF1R signaling contributes to transformation of normal myeloid progenitor cells, but is not required for propagation of the leukemic clone once it has become established. We also show that treatment of mouse MLL-AF9 acute myelogenous leukemia cells with BMS-536924, an IGF1R/insulin receptor-selective tyrosine kinase inhibitor, blocked cell growth, suggesting its efficacy in this model may be due to inhibition of insulin receptor and/or related tyrosine kinases, and raising the possibility that similar IGF1R inhibitors in clinical development may be acting through alternate/related pathways.


Assuntos
Transformação Celular Neoplásica/genética , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Fusão Oncogênica/genética , Receptor IGF Tipo 1/genética , Animais , Benzimidazóis/farmacologia , Western Blotting , Transplante de Medula Óssea , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Feminino , Citometria de Fluxo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Fusão Oncogênica/metabolismo , Pirazóis/farmacologia , Piridonas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/genética , Análise de Sobrevida , Triazinas/farmacologia
3.
Clin Cancer Res ; 18(6): 1808-17, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22287600

RESUMO

PURPOSE: To improve the significance of insulin-like growth factor-binding protein 5 (IGFBP-5) as a prognostic and potentially predictive marker in patients with breast cancer. EXPERIMENTAL DESIGN: Increased IGFBP-5 expression was identified in MCF-7 cells resistant (MCF-7R4) to the IGF-1R/insulin receptor (InsR) inhibitor BMS-536924 and its role examined by targeted knockdown and overexpression in multiple experimental models. Protein expression of IGFBP-5 was measured by immunohistochemistry in a cohort of 76 patients with breast cancer to examine correlative associations with invasive tumor fraction and outcome. The use of a combined IGFBP-5/IGFBP-4 (BPR) expression ratio was applied to predict anti-IGF-1R/InsR response in a panel of breast cancer lines and outcome in multiple breast tumor cohorts. RESULTS: IGFBP-5 knockdown decreased BMS-536924 resistance in MCF-7R4 cells, whereas IGFBP-5 overexpression in MCF-7 cells conferred resistance. When compared with pathologically normal reduction mammoplasty tissue, IGFBP-5 expression levels were upregulated in both invasive and histologically normal adjacent breast cancer tissue. In both univariate and multivariate modeling, metastasis-free survival, recurrence free survival (RFS), and overall survival (OS) were significantly associated with high IGFBP-5 expression. Prognostic power of IGFBP-5 was further increased with the addition of IGFBP-4 where tumors were ranked based upon IGFBP-5/IGFBP-4 expression ratio (BPR). Multiple breast cancer cohorts confirm that BPR (high vs. low) was a strong predictor of RFS and OS. CONCLUSION: IGFBP-5 expression is a marker of poor outcome in patients with breast cancer. An IGFBP-5/IGFBP-4 expression ratio may serve as a surrogate biomarker of IGF pathway activation and predict sensitivity to anti-IGF-1R targeting.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzimidazóis/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Piridonas/uso terapêutico
4.
PLoS One ; 7(12): e51189, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23300537

RESUMO

BACKGROUND: Treatment of metastatic prostate cancer (PCa) with single agents has shown only modest efficacy. We hypothesized dual inhibition of different pathways in PCa results in improved tumor inhibition. The Src family kinases (SFK) and insulin-like growth factor-1 (IGF-1) signaling axes are aberrantly activated in both primary PCa and bone metastases and regulate distinct and overlapping functions in PCa progression. We examined the antitumor effects of combined inhibition of these pathways. MATERIALS AND METHODS: Src andIGF-1 receptor (IGF-1R) inhibition was achieved in vitro by short hairpin (sh)RNA and in vitro and in vivo by small molecule inhibitors (dasatinib and BMS-754807, against SFK and IGF-1R/Insulin Receptor(IR), respectively). RESULTS: In vitro, inhibition of IGF-1 signaling affected cell survival and proliferation. SFK blockade alone had modest effects on proliferation, but significantly enhanced the IGF-1R blockade. These findings correlated with a robust inhibition of IGF-1-induced Akt1 phophorylation by dasatinib, whereas Akt2 phosphorylation was SFK independent and only inhibited by BMS-754807. Thus, complete inhibition of both Akt genes, not seen by either drug alone, is likely a major mechanism for the decreased survival of PCa cells. Furthermore, dasatinib and BMS-754807 inhibited in vivo growth of the primary human xenograft MDA PCa 133, with corresponding inhibition of Akt in tumors. Also, both orthotopic and intratibial tumor growth of PC-3 cells were more potently inhibited by dual SFK and IGF-1R/IR blockade compared to either pathway alone, with a corresponding decrease in bone turnover markers. CONCLUSIONS: Dual IGF-1R/IR and SFK inhibition may be a rational therapeutic approach in PCa by blocking both independent and complementary processes critical to tumor growth.


Assuntos
Apoptose/efeitos dos fármacos , Doenças Ósseas/prevenção & controle , Neoplasias da Próstata/prevenção & controle , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/antagonistas & inibidores , Animais , Western Blotting , Doenças Ósseas/metabolismo , Doenças Ósseas/patologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dasatinibe , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoprecipitação , Masculino , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/farmacologia , Pirimidinas/farmacologia , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Tiazóis/farmacologia , Triazinas/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases da Família src/metabolismo
5.
Cancer Res ; 71(24): 7597-607, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22042792

RESUMO

Insulin-like growth factor (IGF) signaling has been implicated in the resistance to hormonal therapy in breast cancer. Using a model of postmenopausal, estrogen-dependent breast cancer, we investigated the antitumor effects of the dual IGF-1R/InsR tyrosine kinase inhibitor BMS-754807 alone and in combination with letrozole or tamoxifen. BMS-754807 exhibited antiproliferative effects in vitro that synergized strongly in combination with letrozole or 4-hydroxytamoxifen and fulvestrant. Similarly, combined treatment of BMS-754807 with either tamoxifen or letrozole in vivo elicited tumor regressions not achieved by single-agent therapy. Notably, hormonal therapy enhanced the inhibition of IGF-1R/InsR without major side effects in animals. Microarray expression analysis revealed downregulation of cell-cycle control and survival pathways and upregulation of erbB in response to BMS-754807 plus hormonal therapy, particularly tamoxifen. Overall, these results offer a preclinical proof-of-concept for BMS-754807 as an antitumor agent in combination with hormonal therapies in hormone-sensitive breast cancer. Cooperative cell-cycle arrest, decreased proliferation, and enhanced promotion of apoptosis may contribute to antitumor effects to be gauged in future clinical investigations justified by our findings.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Pirazóis/farmacologia , Triazinas/farmacologia , Animais , Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Estrogênios/metabolismo , Feminino , Fulvestranto , Perfilação da Expressão Gênica , Humanos , Letrozol , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nitrilos/administração & dosagem , Nitrilos/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Tamoxifeno/administração & dosagem , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Triazóis/administração & dosagem , Triazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Endocr Relat Cancer ; 18(6): 699-709, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21946410

RESUMO

Epidemiologic and experimental evidence suggest that a subset of breast cancer is insulin responsive, but it is unclear whether safe and effective therapies that target the insulin receptor (IR), which is homologous to oncogenes of the tyrosine kinase class, can be developed. We demonstrate that both pharmacologic inhibition of IR family tyrosine kinase activity and insulin deficiency have anti-neoplastic activity in a model of insulin-responsive breast cancer. Unexpectedly, in contrast to insulin deficiency, pharmacologic IR family inhibition does not lead to significant hyperglycemia and is well tolerated. We show that pharmacokinetic factors explain the tolerability of receptor inhibition relative to insulin deficiency, as the small molecule receptor kinase inhibitor BMS-536924 does not accumulate in muscle at levels sufficient to block insulin-stimulated glucose uptake. Metformin, which lowers insulin levels only in settings of hyperinsulinemia, had minimal activity in this normoinsulinemic model. These findings highlight the importance of tissue-specific drug accumulation as a determinant of efficacy and toxicity of tyrosine kinase inhibitors and suggest that therapeutic targeting of the IR family for cancer treatment is practical.


Assuntos
Aloxano/efeitos adversos , Benzimidazóis/efeitos adversos , Benzimidazóis/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Resistência à Insulina , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Benzimidazóis/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Resistência à Insulina/fisiologia , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Metformina/efeitos adversos , Metformina/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridonas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Resultado do Tratamento
7.
Mol Cancer Ther ; 10(1): 117-25, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21220496

RESUMO

Preclinical investigations have identified insulin-like growth factor (IGF) signaling as a key mechanism for cancer growth and resistance to clinically useful therapies in multiple tumor types including breast cancer. Thus, agents targeting and blocking IGF signaling have promise in the treatment of solid tumors. To identify possible mechanisms of resistance to blocking the IGF pathway, we generated a cell line that was resistant to the IGF-1R/InsR benzimidazole inhibitors, BMS-554417 and BMS-536924, and compared expression profiles of the parental and resistant cells lines using Affymetrix GeneChip Human Genome U133 arrays. Compared with MCF-7 cells, breast cancer resistance protein (BCRP) expression was increased 9-fold in MCF-7R4, which was confirmed by immunoblotting and was highly statistically significant (P = 7.13E-09). BCRP was also upregulated in an independently derived resistant cell line, MCF-7 924R. MCF-7R4 cells had significantly lower intracellular accumulation of BMS-536924 compared with MCF-7 cells. Expression of BCRP in MCF-7 cells was sufficient to reduce sensitivity to BMS-536924. Furthermore, knockdown of BCRP in MCF-7R4 cells resensitized cells to BMS-536924. Four cell lines selected for resistance to the pyrrolotriazine IGF-1R/InsR inhibitor, BMS-754807, did not have upregulation of BCRP. These data suggest that benzimidazole IGF-1R/InsR inhibitors may select for upregulation and be effluxed by the ATP-binding cassette transporter, BCRP, contributing to resistance. However, pyrrolotriazine IGF-1R/InsR inhibitors do not appear to be affected by this resistance mechanism.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Benzimidazóis/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Piridonas/farmacocinética , Receptores de Somatomedina/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/genética , Benzimidazóis/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Piridonas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
Clin Cancer Res ; 17(8): 2314-27, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21177763

RESUMO

PURPOSE: We previously reported an insulin-like growth factor (IGF) gene expression signature, based on genes induced or repressed by IGF-I, which correlated with poor prognosis in breast cancer. We tested whether the IGF signature was affected by anti-IGF-I receptor (IGF-IR) inhibitors and whether the IGF signature correlated with response to a dual anti-IGF-IR/insulin receptor (InsR) inhibitor, BMS-754807. EXPERIMENTAL DESIGN: An IGF gene expression signature was examined in human breast tumors and cell lines and changes were noted following treatment of cell lines or xenografts with anti-IGF-IR antibodies or tyrosine kinase inhibitors. Sensitivity of cells to BMS-754807 was correlated with levels of the IGF signature. Human primary tumorgrafts were analyzed for the IGF signature and IGF-IR levels and activity, and MC1 tumorgrafts were treated with BMS-754807 and chemotherapy. RESULTS: The IGF gene expression signature was reversed in three different models (cancer cell lines or xenografts) treated with three different anti-IGF-IR therapies. The IGF signature was present in triple-negative breast cancers (TNBC) and TNBC cell lines, which were especially sensitive to BMS-754807, and sensitivity was significantly correlated to the expression of the IGF gene signature. The TNBC primary human tumorgraft MC1 showed high levels of both expression and activity of IGF-IR and IGF gene signature score. Treatment of MC1 with BMS-754807 showed growth inhibition and, in combination with docetaxel, tumor regression occurred until no tumor was palpable. Regression was associated with reduced proliferation, increased apoptosis, and mitotic catastrophe. CONCLUSIONS: These studies provide a clear biological rationale to test anti-IGF-IR/InsR therapy in combination with chemotherapy in patients with TNBC.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Triazinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Análise por Conglomerados , Docetaxel , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Immunoblotting , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células NIH 3T3 , Pirazóis/administração & dosagem , Receptor ErbB-2/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Receptores Estrogênicos/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxoides/administração & dosagem , Taxoides/farmacologia , Triazinas/administração & dosagem
9.
Cancer Res ; 71(3): 1060-70, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21148487

RESUMO

The insulin-like growth factor (IGF) 1 receptor (IGF1R) is an important therapeutic target under study in many cancers. Here, we describe a breast cancer model based on expression of the ETV6-NTRK3 (EN) chimeric tyrosine kinase that suggests novel therapeutic applications of IGF1R inhibitors in secretory breast cancers. Originally discovered in congenital fibrosarcomas with t(12;15) translocations, EN was identified subsequently in secretory breast carcinoma (SBC) which represent a variant of invasive ductal carcinoma. Because fibroblast transformation by EN requires the IGF1R axis, we hypothesized a similar dependency may exist in mammary cells and, if so, that IGF1R inhibitors might be useful to block EN-driven breast oncogenesis. In this study, we analyzed EN expressing murine and human mammary epithelial cell lines for transformation properties. Various IGF1R signaling inhibitors, including the dual specificity IGF1R/insulin receptor (INSR) inhibitor BMS-536924, were then tested for effects on three-dimensional Matrigel cell growth, migration, and tumor formation. We found that EN expression increased acinar size and luminal filling in Matrigel cultures and promoted orthotopic tumor growth in mice. Tumors were well differentiated and nonmetastatic, similar to human SBC. The known EN effector pathway, PI3K-Akt, was activated in an IGF1- or insulin-dependent manner. BMS-536924 blocked EN transformation in vitro, whereas BMS-754807, another IGIFR/INSR kinase inhibitor currently in clinical trials, significantly reduced tumor growth in vivo. Importantly, EN model systems mimic the clinical phenotype observed in human SBC. Moreover, EN has a strict requirement for IGF1R or INSR in breast cell transformation. Thus, our findings strongly encourage the evaluation of IGF1R/INSR inhibitors to treat EN-driven breast cancers.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Fusão Oncogênica/biossíntese , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Animais , Benzimidazóis/farmacologia , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Transformação Celular Neoplásica , Transição Epitelial-Mesenquimal , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Camundongos , Camundongos Transgênicos , Terapia de Alvo Molecular , Proteína Oncogênica v-akt/metabolismo , Piridonas/farmacologia , Transdução de Sinais , Transplante Heterólogo
10.
Cancer Res ; 70(21): 8770-81, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20959493

RESUMO

The insulin-like growth factor-1 receptor (IGF1R) is emerging as a promising therapeutic target in human cancers. In the high-risk childhood sarcomas Ewing family tumor and rhabdomyosarcoma, IGF1R-blocking antibodies show impressive antitumor activity in some but not all patients, and acquired resistance is observed. Because tumor IGF1R mutations are not described, the basis of IGF1R inhibitor resistance remains unknown. We hypothesized that compensatory signaling cascades bypassing targeted IGF1R inhibition might be involved. To test this systematically, we performed small interfering RNA (siRNA) screens in sarcoma cell lines to identify IGF1R pathway components or related protein tyrosine kinase (PTK) networks that modulate the antitumor efficacy of the BMS-536924 IGF1R kinase inhibitor. This strategy revealed (a) that sarcoma cells are exquisitely sensitive to loss of distal rather than proximal IGF1R signaling components, such as ribosomal protein S6 (RPS6); (b) that BMS-536924 fails to block RPS6 activation in resistant sarcoma cell lines; and (c) that siRNA knockdown of the macrophage-stimulating 1 receptor tyrosine kinase (MST1R; also known as RON) restores BMS-536924 efficacy, even in highly drug-resistant cell lines. We confirmed MST1R expression across a broad panel of childhood sarcomas, and found that loss of MST1R by RNA interference blocks downstream RPS6 activation when combined with BMS-536924 in vitro. These findings underscore the importance of fully understanding PTK networks for successful clinical implementation of kinase inhibitor strategies.


Assuntos
RNA Interferente Pequeno/farmacologia , Receptores Proteína Tirosina Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Proteína S6 Ribossômica/metabolismo , Sarcoma/metabolismo , Apoptose/efeitos dos fármacos , Benzimidazóis/farmacologia , Western Blotting , Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Genes Letais , Humanos , Técnicas Imunoenzimáticas , Células-Tronco Mesenquimais/metabolismo , Piridonas/farmacologia , RNA Mensageiro/genética , Receptores Proteína Tirosina Quinases/genética , Receptor IGF Tipo 1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína S6 Ribossômica/genética , Sarcoma/tratamento farmacológico , Sarcoma/genética , Transdução de Sinais , Células Tumorais Cultivadas
11.
Cancer Res ; 70(18): 7221-31, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20807811

RESUMO

Agents targeting insulin-like growth factor-I receptor (IGF-IR), including antibodies and small-molecule inhibitors, are currently in clinical development for the treatment of cancers including sarcoma. However, development of resistance is a common phenomenon resulting in failures of anticancer therapies. In light of this problem, we developed two resistant models from the rhabdomyosarcoma cell line Rh41: Rh41-807R, with acquired resistance to BMS-754807, a small-molecule dual-kinase inhibitor targeting IGF-IR and insulin receptor (IR), and Rh41-MAB391R, with resistance to MAB391, an IGF-IR-blocking antibody. In addition, tumor xenograft models were established from Rh41 and Rh41-807R cell lines. Gene expression and DNA copy number analyses of these models revealed shared as well as unique acquired resistance mechanisms for the two types of IGF-IR inhibitors. Each resistant model used different signaling pathways as a mechanism for proliferation. Platelet-derived growth factor receptor α (PDGFRα) was amplified, overexpressed, and constitutively activated in Rh41-807R cells and tumors. Knockdown of PDGFRα by small interfering RNA in Rh41-807R resensitized the cells to BMS-754807. Synergistic activities were observed when BMS-754807 was combined with PDGFRα inhibitors in the Rh41-807R model in vitro. In contrast, AXL expression was highly elevated in Rh41-MAB391R but downregulated in Rh41-807R. Notably, BMS-754807 was active in Rh41-MAB391R cells and able to overcome resistance to MAB391, but MAB391 was not active in Rh41-807R cells, suggesting potentially broader clinical activity of BMS-754807. This is the first study to define and compare acquired resistance mechanisms for IGF-IR-targeted therapies. It provides insights into the differential acquired resistance mechanisms for IGF-IR/IR small-molecule inhibitor versus anti-IGF-IR antibody.


Assuntos
Anticorpos Monoclonais/farmacologia , Pirazóis/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Rabdomiossarcoma/terapia , Triazinas/farmacologia , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Receptor IGF Tipo 1/biossíntese , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/imunologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/agonistas , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/deficiência , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genética , Rabdomiossarcoma/imunologia , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Bioorg Med Chem Lett ; 20(17): 5027-30, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20675137

RESUMO

Pyrrolidine, pyrrolidinone, carbocyclic, and acyclic groups were used as isosteric proline replacements in a series of insulin-like growth factor I receptor kinase/insulin receptor kinase inhibitors. Examples that were similar in potency to proline-containing reference compounds were shown to project a key fluoropyridine amide into a common space, while less potent compounds were not able to do so for reasons of stereochemistry or structural rigidity.


Assuntos
Prolina/química , Inibidores de Proteínas Quinases/química , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Triazinas/química , Modelos Moleculares , Inibidores de Proteínas Quinases/farmacologia , Triazinas/farmacologia
13.
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
14.
Bioorg Med Chem Lett ; 20(10): 3182-5, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20399649

RESUMO

A series of 3-[6-(4-substituted-piperazin-1-yl)-4-methyl-1H-benzimidazol-2-yl]-1H-pyridine-2-one were synthesized to modulate CYP3A4 inhibition and improve aqueous solubility of our prototypical compound BMS-536924 (1), while maintaining potent IGF-1R inhibitory activity. Structure-activity and structure-solubility studies led to the identification of BMS-577098 (27), which demonstrates oral in vivo efficacy in animal models. The improvement was achieved by replacing morpholine with more polar bio-isoster piperazine and modulating the basicity of distal nitrogen with appropriate substitutions.


Assuntos
Benzimidazóis/química , Piperazinas/química , Inibidores de Proteínas Quinases/química , Piridonas/química , Administração Oral , Animais , Benzimidazóis/síntese química , Benzimidazóis/farmacocinética , Benzimidazóis/farmacologia , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A , Humanos , Camundongos , Camundongos Nus , Piperazinas/síntese química , Piperazinas/farmacocinética , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Piridonas/síntese química , Piridonas/farmacocinética , Piridonas/farmacologia , Ratos , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Endocr Relat Cancer ; 17(3): 623-36, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20385747

RESUMO

Neuroendocrine (carcinoid) tumors (NETs) are endocrine neoplasms occurring most frequently in gastrointestinal and bronchopulmonary (BP) systems. The majority of patients present with advanced disease for which few treatment options exist. We assessed 104 NETs (74 cases) for biomarkers targeted by anticancer drugs under development for other forms of cancer. Activating mutations were assessed in epidermal growth factor receptor (EGFR), stem cell factor receptor (KIT), and platelet-derived growth factor receptor alpha (PDGFRA), as well as non-response mutations in KRAS. Copy number of EGFR and HER-2/neu was quantified with fluorescence in situ hybridization. Immunohistochemical analyses were performed for EGFR, KIT, PDGFRA, somatostatin receptor subtypes 2A and 5 (SSTR5), vascular endothelial growth factor receptor 1, mammalian target of rapamycin (mTOR), insulin-like growth factor 1 receptor (IGF1R), heat shock protein 90 (Hsp90), and transforming growth factor-beta receptor 1 (TGFBR1). NETs lacked HER2-overexpression predictive of anti-HER2 response and KIT and PDGFRA activating mutations indicative of imatinib sensitivity. High EGFR aneusomy (20% of all cases) and elevated EGFR copy number (39%) were found, but few KRAS mutations associated with non-response to anti-EGFR therapy (3%). Hsp90, TGFBR1, IGF1R, and SSTR5 exhibited highest levels of immunohistochemical staining in the largest percents of tumors. In subsequent in vitro studies, anticancer drug 17-(allylamino)-17-demethoxygeldanamycin (17-AAG) (targeting Hsp90) inhibited proliferation of BP NET lines NCI-H727, NCI-H720, and NCI-H835 with IC(50) values of 70.4, 310, and 788 nM respectively; BMS-754807 (targeting IGF1R/IR) inhibited growth with IC(50) values of 428 nM, 2.8 microM, and 1 microM. At growth-inhibiting concentrations, 17-AAG (24 h) induced loss of EGFR and IGF1R in the IGF1R-expressing NCI-H727 line, and BMS-754807 (24 h) inhibited constitutive IGF1R autophosphorylation. Our results support further research into Hsp90, IGF1R, and EGFR as targets for developing new anticancer therapeutics for some NETs.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzoquinonas/farmacologia , Biomarcadores Tumorais/genética , Western Blotting , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactamas Macrocíclicas/farmacologia , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia , Reação em Cadeia da Polimerase , Pirazóis/farmacologia , Estudos Retrospectivos , Análise Serial de Tecidos , Triazinas/farmacologia , Adulto Jovem
16.
Bioorg Med Chem Lett ; 20(5): 1744-8, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20153189
17.
Cancer Res ; 70(2): 741-51, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20068149

RESUMO

Epidemiologic studies suggest that type 2 diabetes (T2D) increases breast cancer risk and mortality, but there is limited experimental evidence supporting this association. Moreover, there has not been any definition of a pathophysiological pathway that diabetes may use to promote tumorigenesis. In the present study, we used the MKR mouse model of T2D to investigate molecular mechanisms that link T2D to breast cancer development and progression. MKR mice harbor a transgene encoding a dominant-negative, kinase-dead human insulin-like growth factor-I receptor (IGF-IR) that is expressed exclusively in skeletal muscle, where it acts to inactivate endogenous insulin receptor (IR) and IGF-IR. Although lean female MKR mice are insulin resistant and glucose intolerant, displaying accelerated mammary gland development and enhanced phosphorylation of IR/IGF-IR and Akt in mammary tissue, in the context of three different mouse models of breast cancer, these metabolic abnormalities were found to accelerate the development of hyperplastic precancerous lesions. Normal or malignant mammary tissue isolated from these mice exhibited increased phosphorylation of IR/IGF-IR and Akt, whereas extracellular signal-regulated kinase 1/2 phosphorylation was largely unaffected. Tumor-promoting effects of T2D in the models were reversed by pharmacological blockade of IR/IGF-IR signaling by the small-molecule tyrosine kinase inhibitor BMS-536924. Our findings offer compelling experimental evidence that T2D accelerates mammary gland development and carcinogenesis,and that the IR and/or the IGF-IR are major mediators of these effects.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Hiperinsulinismo/metabolismo , Neoplasias Mamárias Experimentais/etiologia , Neoplasias Mamárias Experimentais/metabolismo , Animais , Benzimidazóis/farmacologia , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Feminino , Hiperinsulinismo/sangue , Hiperinsulinismo/patologia , Insulina/sangue , Glândulas Mamárias Animais/crescimento & desenvolvimento , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Transgênicos , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Piridonas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/metabolismo
18.
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
19.
Cancer Res ; 69(19): 7635-43, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19789352

RESUMO

The insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) are receptor tyrosine kinases that participate in mitogenic and antiapoptotic signaling in normal and neoplastic epithelia. In the present study, immunoblotting and reverse transcription-PCR demonstrated expression of IGF1R and IR isoform A in acute myelogenous leukemia (AML) cell lines as well as in >80% of clinical AML isolates. Treatment with insulin enhanced signaling through the Akt and MEK1/2 pathways as well as survival of serum-starved AML cell lines. Conversely, treatment with BMS-536924, a dual IGF1R/IR kinase inhibitor that is undergoing preclinical testing, inhibited constitutive receptor phosphorylation as well as downstream signaling through MEK1/2 and Akt. These changes inhibited proliferation and, in some AML cell lines, induced apoptosis at submicromolar concentrations. Likewise, BMS-536924 inhibited leukemic colony formation in CD34+ clinical AML samples in vitro. Collectively, these results not only indicate that expression of IGF1R and IR isoform A is common in AML but also show that interruption of signaling from these receptors inhibits proliferation in clinical AML isolates. Accordingly, further investigation of IGF1R/IR axis as a potential therapeutic target in AML appears warranted.


Assuntos
Benzimidazóis/farmacologia , Leucemia Mieloide Aguda/enzimologia , Piridonas/farmacologia , Receptor IGF Tipo 1/biossíntese , Receptor de Insulina/biossíntese , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Células HL-60 , Humanos , Fator de Crescimento Insulin-Like I/biossíntese , Células K562 , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Isoformas de Proteínas , Inibidores de Proteínas Quinases/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Células U937
20.
J Med Chem ; 52(23): 7360-3, 2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-19778024
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