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1.
Nat Commun ; 10(1): 2235, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138805

RESUMO

Pediatric high-grade glioma (pHGG) and diffuse intrinsic pontine gliomas (DIPGs) are aggressive pediatric brain tumors in desperate need of a curative treatment. Oncolytic virotherapy is emerging as a solid therapeutic approach. Delta-24-RGD is a replication competent adenovirus engineered to replicate in tumor cells with an aberrant RB pathway. This virus has proven to be safe and effective in adult gliomas. Here we report that the administration of Delta-24-RGD is safe in mice and results in a significant increase in survival in immunodeficient and immunocompetent models of pHGG and DIPGs. Our results show that the Delta-24-RGD antiglioma effect is mediated by the oncolytic effect and the immune response elicited against the tumor. Altogether, our data highlight the potential of this virus as treatment for patients with these tumors. Of clinical significance, these data have led to the start of a phase I/II clinical trial at our institution for newly diagnosed DIPG (NCT03178032).


Assuntos
Adenoviridae , Neoplasias do Tronco Encefálico/terapia , Glioma/terapia , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Neoplasias do Tronco Encefálico/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Simulação por Computador , Modelos Animais de Doenças , Glioma/patologia , Humanos , Técnicas In Vitro , Camundongos , Gradação de Tumores , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Blood ; 133(22): 2401-2412, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-30975638

RESUMO

Refractory or relapsed diffuse large B-cell lymphoma (DLBCL) often associates with the activated B-cell-like (ABC) subtype and genetic alterations that drive constitutive NF-κB activation and impair B-cell terminal differentiation. Here, we show that DNA damage response by p53 is a central mechanism suppressing the pathogenic cooperation of IKK2ca-enforced canonical NF-κB and impaired differentiation resulting from Blimp1 loss in ABC-DLBCL lymphomagenesis. We provide evidences that the interplay between these genetic alterations and the tumor microenvironment select for additional molecular addictions that promote lymphoma progression, including aberrant coexpression of FOXP1 and the B-cell mutagenic enzyme activation-induced deaminase, and immune evasion through major histocompatibility complex class II downregulation, PD-L1 upregulation, and T-cell exhaustion. Consistently, PD-1 blockade cooperated with anti-CD20-mediated B-cell cytotoxicity, promoting extended T-cell reactivation and antitumor specificity that improved long-term overall survival in mice. Our data support a pathogenic cooperation among NF-κB-driven prosurvival, genetic instability, and immune evasion mechanisms in DLBCL and provide preclinical proof of concept for including PD-1/PD-L1 blockade in combinatorial immunotherapy for ABC-DLBCL.


Assuntos
Linfócitos B/imunologia , Antígeno B7-H1/imunologia , Regulação Neoplásica da Expressão Gênica , Ativação Linfocitária , Linfoma Difuso de Grandes Células B/imunologia , Receptor de Morte Celular Programada 1/imunologia , Evasão Tumoral , Proteína Supressora de Tumor p53/imunologia , Animais , Linfócitos B/patologia , Antígeno B7-H1/genética , Feminino , Humanos , Imunoterapia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/terapia , Masculino , Camundongos , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/genética , Linfócitos T/imunologia , Linfócitos T/patologia , Proteína Supressora de Tumor p53/genética
3.
J Med Chem ; 61(15): 6518-6545, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-29953809

RESUMO

Using knowledge- and structure-based approaches, we designed and synthesized reversible chemical probes that simultaneously inhibit the activity of two epigenetic targets, histone 3 lysine 9 methyltransferase (G9a) and DNA methyltransferases (DNMT), at nanomolar ranges. Enzymatic competition assays confirmed our design strategy: substrate competitive inhibitors. Next, an initial exploration around our hit 11 was pursued to identify an adequate tool compound for in vivo testing. In vitro treatment of different hematological neoplasia cell lines led to the identification of molecules with clear antiproliferative efficacies (GI50 values in the nanomolar range). On the basis of epigenetic functional cellular responses (levels of lysine 9 methylation and 5-methylcytosine), an acceptable therapeutic window (around 1 log unit) and a suitable pharmacokinetic profile, 12 was selected for in vivo proof-of-concept ( Nat. Commun. 2017 , 8 , 15424 ). Herein, 12 achieved a significant in vivo efficacy: 70% overall tumor growth inhibition of a human acute myeloid leukemia (AML) xenograft in a mouse model.


Assuntos
Antineoplásicos/farmacologia , Metilases de Modificação do DNA/antagonistas & inibidores , Desenho de Drogas , Inibidores Enzimáticos/farmacologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Metilases de Modificação do DNA/química , Metilases de Modificação do DNA/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacocinética , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Camundongos , Simulação de Acoplamento Molecular , Conformação Proteica , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Haematologica ; 103(6): 1065-1072, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29191842

RESUMO

Regulatory T (Treg) cells can weaken antitumor immune responses, and inhibition of their function appears to be a promising therapeutic approach in cancer patients. Mice with targeted deletion of the gene encoding the Cl-/HCO3- anion exchanger AE2 (also termed SLC4A2), a membrane-bound carrier involved in intracellular pH regulation, showed a progressive decrease in the number of Treg cells. We therefore challenged AE2 as a potential target for tumor therapy, and generated linear peptides designed to bind the third extracellular loop of AE2, which is crucial for its exchange activity. Peptide p17AE2 exhibited optimal interaction ability and indeed promoted apoptosis in mouse and human Treg cells, while activating effector T-cell function. Interestingly, this linear peptide also induced apoptosis in different types of human leukemia, lymphoma and multiple myeloma cell lines and primary malignant samples, while it showed only moderate effects on normal B lymphocytes. Finally, a macrocyclic AE2 targeting peptide exhibiting increased stability in vivo was effective in mice xenografted with B-cell lymphoma. These data suggest that targeting the anion exchanger AE2 with specific peptides may represent an effective therapeutic approach in B-cell malignancies.


Assuntos
Antineoplásicos/farmacologia , Antiportadores de Cloreto-Bicarbonato/antagonistas & inibidores , Leucemia de Células B/metabolismo , Linfoma de Células B/metabolismo , Peptídeos/farmacologia , Animais , Ânions/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Leucemia de Células B/tratamento farmacológico , Leucemia de Células B/patologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nat Commun ; 8: 15424, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28548080

RESUMO

The indisputable role of epigenetics in cancer and the fact that epigenetic alterations can be reversed have favoured development of epigenetic drugs. In this study, we design and synthesize potent novel, selective and reversible chemical probes that simultaneously inhibit the G9a and DNMTs methyltransferase activity. In vitro treatment of haematological neoplasia (acute myeloid leukaemia-AML, acute lymphoblastic leukaemia-ALL and diffuse large B-cell lymphoma-DLBCL) with the lead compound CM-272, inhibits cell proliferation and promotes apoptosis, inducing interferon-stimulated genes and immunogenic cell death. CM-272 significantly prolongs survival of AML, ALL and DLBCL xenogeneic models. Our results represent the discovery of first-in-class dual inhibitors of G9a/DNMTs and establish this chemical series as a promising therapeutic tool for unmet needs in haematological tumours.


Assuntos
Antineoplásicos/farmacologia , Metilases de Modificação do DNA/antagonistas & inibidores , Desenho de Drogas , Inibidores Enzimáticos/farmacologia , Neoplasias Hematológicas/tratamento farmacológico , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cristalografia por Raios X , Metilases de Modificação do DNA/química , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/uso terapêutico , Epigênese Genética/efeitos dos fármacos , Feminino , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Interferons/imunologia , Interferons/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos , Simulação de Acoplamento Molecular , Análise de Sobrevida , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Oncotarget ; 7(25): 37407-37419, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27270648

RESUMO

Although conventional therapies for acute myeloid leukemia (AML) and diffuse large B-cell lymphoma (DLBCL) are effective in inducing remission, many patients relapse upon treatment. Hence, there is an urgent need for novel therapies. PIM kinases are often overexpressed in AML and DLBCL and are therefore an attractive therapeutic target. However, in vitro experiments have demonstrated that intrinsic resistance to PIM inhibition is common. It is therefore likely that only a minority of patients will benefit from single agent PIM inhibitor treatment. In this study, we performed an shRNA-based genetic screen to identify kinases whose suppression is synergistic with PIM inhibition. Here, we report that suppression of p38α (MAPK14) is synthetic lethal with the PIM kinase inhibitor AZD1208. PIM inhibition elevates reactive oxygen species (ROS) levels, which subsequently activates p38α and downstream AKT/mTOR signaling. We found that p38α inhibitors sensitize hematological tumor cell lines to AZD1208 treatment in vitro and in vivo. These results were validated in ex vivo patient-derived AML cells. Our findings provide mechanistic and translational evidence supporting the rationale to test a combination of p38α and PIM inhibitors in clinical trials for AML and DLBCL.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Camundongos Transgênicos , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Breast Cancer Res ; 13(1): R11, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21276249

RESUMO

INTRODUCTION: Tumors that express estrogen receptor alpha (ERα+) comprise 75% of breast cancers in women. While treatments directed against this receptor have successfully lowered mortality rates, many primary tumors initially or later exhibit resistance. The paucity of murine models of this "luminal" tumor subtype has hindered studies of factors that promote their pathogenesis and modulate responsiveness to estrogen-directed therapeutics. Since epidemiologic studies closely link prolactin and the development of ERα+ tumors in women, we examined characteristics of the aggressive ERα+ and ERα- carcinomas which develop in response to mammary prolactin in a murine transgenic model (neu-related lipocalin- prolactin (NRL-PRL)). To evaluate their relationship to clinical tumors, we determined phenotypic relationships among these carcinomas, other murine models of breast cancer, and features of luminal tumors in women. METHODS: We examined a panel of prolactin-induced tumors for characteristics relevant to clinical tumors: histotype, ERα/progesterone receptor (PR) expression and estrogen responsiveness, Activating Protein 1 (AP-1) components, and phosphorylation of signal transducer and activator of transcription 5 (Stat5), extracellular signal regulated kinase (ERK) 1/2 and AKT. We compared levels of transcripts in the ERα-associated "luminal" signature that defines this subtype of tumors in women and transcripts enriched in various mammary epithelial lineages to other well-studied genetically modified murine models of breast cancer. Finally, we used microarray analyses to compare prolactin-induced ERα+ and ERα- tumors, and examined responsiveness to estrogen and the anti-estrogen, Faslodex, in vivo. RESULTS: Prolactin-induced carcinomas were markedly diverse with respect to histotype, ERα/PR expression, and activated signaling cascades. They constituted a heterogeneous, but distinct group of murine mammary tumors, with molecular features of the luminal subtype of human breast cancer. In contrast to morphologically normal and hyperplastic structures in NRL-PRL females, carcinomas were insensitive to ERα-mediated signals. These tumors were distinct from mouse mammary tumor virus (MMTV)-neu tumors, and contained elevated transcripts for factors associated with luminal/alveolar expansion and differentiation, suggesting that they arose from physiologic targets of prolactin. These features were shared by ERα+ and ERα- tumors, suggesting a common origin, although the former exhibited transcript profiles reflecting greater differentiation. CONCLUSIONS: Our studies demonstrate that prolactin can promote diverse carcinomas in mice, many of which resemble luminal breast cancers, providing a novel experimental model to examine the pathogenesis, progression and treatment responsiveness of this tumor subtype.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Estrogênios/fisiologia , Neoplasias Mamárias Experimentais/metabolismo , Prolactina/genética , Animais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Carcinoma/genética , Análise por Conglomerados , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Neoplasias Mamárias Experimentais/etiologia , Neoplasias Mamárias Experimentais/genética , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Prolactina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição AP-1/metabolismo
8.
J Endocrinol ; 203(1): 99-110, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19635758

RESUMO

Epidemiologic studies have demonstrated that increased prolactin (PRL) exposure raises the risk of invasive estrogen receptor alpha (ERalpha)-positive breast cancer in women. However, the mechanism(s) whereby this occurs and the interactions with estrogen itself in this disease remain poorly understood. In order to investigate the role of ovarian hormones in the disease process, we employed a transgenic model neu-related lipocalin (NRL)-PRL in which transgenic PRL is directed to mammary epithelial cells by the PRL- and estrogen-insensitive NRL promoter, mimicking the endogenous PRL expression within the breast observed in women. This high local exposure leads to mammary lesion development and eventually carcinomas. Ovariectomy (ovx), shortly after puberty, did not alter the incidence or latency of PRL-induced mammary carcinomas, consistent with the independence of PRL from circulating estrogens as a risk factor for invasive breast cancer in women. However, chronic estrogen administration to ovx NRL-PRL females decreased the latency of both ERalpha-positive and -negative tumors. We identified multiple mechanisms that may underlie this observation. Elevated estrogen exposure cooperated with PRL to increase epithelial proliferation and myoepithelial abnormalities, increasing the incidence of preneoplastic lesions. Critical components of the extracellular matrix secreted by the myoepithelium were reduced with age, and transgenic PRL raised transcripts for tenascin-C and maspin, both associated with tumor progression and poor prognosis in subclasses of clinical breast tumors. Mammary pERK1/2 and pAkt, but not phosphorylated Stat5, were markedly elevated by local PRL. Together, these findings indicate that PRL employs multiple mechanisms to promote mammary tumorigenesis.


Assuntos
Envelhecimento/metabolismo , Estrogênios/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Lesões Pré-Cancerosas/metabolismo , Prolactina/metabolismo , Animais , Proliferação de Células , Estradiol , Receptor alfa de Estrogênio/metabolismo , Feminino , Expressão Gênica , Glândulas Mamárias Animais/fisiologia , Camundongos , Camundongos Transgênicos , Processos Neoplásicos , Transdução de Sinais
9.
Clin Cancer Res ; 8(2): 347-53, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11839648

RESUMO

BACKGROUND: The full-length receptor p185HER-2 undergoes a metalloprotease-dependent cleavage producing a membrane-associated fragment (p95HER-2) in cultured breast cancer cells. P95HER-2 has potentially enhanced signaling activity, but its expression and role in human breast cancer is poorly characterized. PURPOSE: The purpose of this project was to characterize the expression of p95HER-2 in primary breast cancers and nodal metastasis, and to study association with clinicopathological factors. EXPERIMENTAL DESIGN: P95HER-2 and p185HER-2 were examined in 337 primary breast tumors and 81 metastatic lymph nodes by Western blot analysis, and tested for associations with other clinicopathological factors. RESULTS: P95HER-2 was present in 20.9% of primary tumors from node-negative patients, in 29.1% from patients with one to three metastatic nodes, and in 36.7% from patients with four or more metastatic nodes (P = 0.027). Whereas p185HER-2 overexpression was unrelated to nodal disease (P = 0.63), the odds of lymph node metastasis were enhanced 2.9-fold by the presence of p95HER-2 (48.8% of node-negative versus 73.5% of node-positive patients; P = 0.03; odds ratio = 2.9). P95HER-2 was more frequent in metastatic lymph nodes than in primary tumors (45.7% versus 26.7%; P = 0.0009), whereas p185HER-2 overexpression was similar in both (22.3% versus 23.5%; P = 0.933). P95HER-2 did not significantly correlate with patient age, tumor size, stage, histotype, or hormone receptor status. CONCLUSIONS: P95HER-2 in primary tumors was related to extent of lymph node involvement and was enhanced in nodal tissue suggesting an important role as a marker or cause in breast cancer metastasis. Examination of the prognostic value of p95HER-2 in breast cancer and its coexpression with metalloprotease activity seem warranted.


Assuntos
Neoplasias da Mama/patologia , Metástase Linfática , Receptor ErbB-2/biossíntese , Receptor ErbB-2/química , Idoso , Western Blotting , Neoplasias da Mama/metabolismo , Feminino , Humanos , Ligantes , Pessoa de Meia-Idade , Prognóstico , Estrutura Terciária de Proteína , Fatores de Risco , Células Tumorais Cultivadas
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