RESUMO
Endothelial Notch signaling is critical for tumor angiogenesis. Notch1 blockade can interfere with tumor vessel function but causes tissue hypoxia and gastrointestinal toxicity. Notch4 is primarily expressed in endothelial cells, where it may promote angiogenesis; however, effective therapeutic targeting of Notch4 has not been successful. We developed highly specific Notch4-blocking antibodies, 6-3-A6 and humanized E7011, allowing therapeutic targeting of Notch4 to be assessed in tumor models. Notch4 was expressed in tumor endothelial cells in multiple cancer models, and endothelial expression was associated with response to E7011/6-3-A6. Anti-Notch4 treatment significantly delayed tumor growth in mouse models of breast, skin, and lung cancers. Enhanced tumor inhibition occurred when anti-Notch4 treatment was used in combination with chemotherapeutics. Endothelial transcriptomic analysis of murine breast tumors treated with 6-3-A6 identified significant changes in pathways of vascular function but caused only modest change in canonical Notch signaling. Analysis of early and late treatment timepoints revealed significant differences in vessel area and perfusion in response to anti-Notch4 treatment. We conclude that targeting Notch4 improves tumor growth control through endothelial intrinsic mechanisms. SIGNIFICANCE: A first-in-class anti-Notch4 agent, E7011, demonstrates strong antitumor effects in murine tumor models including breast carcinoma. Endothelial Notch4 blockade reduces perfusion and vessel area.
Assuntos
Anticorpos Neutralizantes , Neovascularização Patológica , Receptor Notch4 , Animais , Receptor Notch4/metabolismo , Camundongos , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Neovascularização Patológica/metabolismo , Feminino , Anticorpos Neutralizantes/farmacologia , Anticorpos Neutralizantes/uso terapêutico , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismoRESUMO
The Wnt/ß-catenin signaling pathway plays crucial roles in embryonic development and the development of multiple types of cancer, and its aberrant activation provides cancer cells with escape mechanisms from immune checkpoint inhibitors. E7386, an orally active selective inhibitor of the interaction between ß-catenin and CREB binding protein, which is part of the Wnt/ß-catenin signaling pathway, disrupts the Wnt/ß-catenin signaling pathway in HEK293 and adenomatous polyposis coli (APC)-mutated human gastric cancer ECC10 cells. It also inhibited tumor growth in an ECC10 xenograft model and suppressed polyp formation in the intestinal tract of ApcMin /+ mice, in which mutation of Apc activates the Wnt/ß-catenin signaling pathway. E7386 demonstrated antitumor activity against mouse mammary tumors developed in mouse mammary tumor virus (MMTV)-Wnt1 transgenic mice. Gene expression profiling using RNA sequencing data of MMTV-Wnt1 tumor tissue from mice treated with E7386 showed that E7386 downregulated genes in the hypoxia signaling pathway and immune responses related to the CCL2, and IHC analysis showed that E7386 induced infiltration of CD8+ cells into tumor tissues. Furthermore, E7386 showed synergistic antitumor activity against MMTV-Wnt1 tumor in combination with anti-PD-1 antibody. In conclusion, E7386 demonstrates clear antitumor activity via modulation of the Wnt/ß-catenin signaling pathway and alteration of the tumor and immune microenvironments, and its antitumor activity can be enhanced in combination with anti-PD-1 antibody. SIGNIFICANCE: These findings demonstrate that the novel anticancer agent, E7386, modulates Wnt/ß-catenin signaling, altering the tumor immune microenvironment and exhibiting synergistic antitumor activity in combination with anti-PD-1 antibody.
Assuntos
Antineoplásicos/farmacologia , Neoplasias/patologia , Fragmentos de Peptídeos/metabolismo , Pirazinas/farmacologia , Sialoglicoproteínas/metabolismo , Triazinas/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Antineoplásicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Genes APC , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Fragmentos de Peptídeos/antagonistas & inibidores , Ligação Proteica/efeitos dos fármacos , Pirazinas/uso terapêutico , Sialoglicoproteínas/antagonistas & inibidores , Triazinas/uso terapêutico , Via de Sinalização Wnt/genética , Proteína Wnt1/genética , Proteína Wnt1/metabolismo , beta Catenina/antagonistas & inibidoresRESUMO
The FGFR signaling pathway has a crucial role in proliferation, survival, and migration of cancer cells, tumor angiogenesis, and drug resistance. FGFR genetic abnormalities, such as gene fusion, mutation, and amplification, have been implicated in several types of cancer. Therefore, FGFRs are considered potential targets for cancer therapy. E7090 is an orally available and selective inhibitor of the tyrosine kinase activities of FGFR1, -2, and -3. In kinetic analyses of the interaction between E7090 and FGFR1 tyrosine kinase, E7090 associated more rapidly with FGFR1 than did the type II FGFR1 inhibitor ponatinib, and E7090 dissociated more slowly from FGFR1, with a relatively longer residence time, than did the type I FGFR1 inhibitor AZD4547, suggesting that its kinetics are more similar to the type V inhibitors, such as lenvatinib. E7090 showed selective antiproliferative activity against cancer cell lines harboring FGFR genetic abnormalities and decreased tumor size in a mouse xenograft model using cell lines with dysregulated FGFR Furthermore, E7090 administration significantly prolonged the survival of mice with metastasized tumors in the lung. Our results suggest that E7090 is a promising candidate as a therapeutic agent for the treatment of tumors harboring FGFR genetic abnormalities. It is currently being investigated in a phase I clinical trial. Mol Cancer Ther; 15(11); 2630-9. ©2016 AACR.
Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Inativação Gênica , Humanos , Camundongos , Mortalidade , Mutação , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Inibidores de Proteínas Quinases/química , Interferência de RNA , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Liposomal anticancer agents can effectively deliver drugs to tumor lesions, but their therapeutic effects are enhanced in only limited number of patients. Appropriate biomarkers to identify responder patients to these liposomal agents will improve their treatment efficacies. We carried out pharmacological and histopathological analyses of mouse xenograft models bearing human ovarian cancers (Caov-3, SK-OV-3, KURAMOCHI, and TOV-112D) to correlate the therapeutic effects of doxorubicin-encapsulated liposome (Doxil(®) ) and histological characteristics linked to the enhanced permeability and retention effect. We next generated (111) In-encapsulated liposomes to examine their capacities to determine indications for Doxil(®) treatment by single-photon emission computed tomography (SPECT)/CT imaging. Antitumor activities of Doxil(®) were drastically enhanced in Caov-3, moderately in SK-OV-3, and minimally in KURAMOCHI and TOV-112D when compared to doxorubicin. Microvessel density and vascular perfusion were high in Caov-3 and SK-OV-3, indicating a close relation with the enhanced antitumor effects. Next, (111) In-encapsulated liposomes were given i.v. to the animals. Their tumor accumulation and area under the curve values over 72 h were high in Caov-3, relatively high in SK-OV-3, and low in two other tumors. Importantly, as both Doxil(®) effects and liposomal accumulation varied in the SK-OV-3 group, we individually obtained SPECT/CT images of SK-OV-3-bearing mouse (n = 11) before Doxil(®) treatment. Clear correlation between liposomal tumor accumulation and effects of Doxil(®) was confirmed (R(2) = 0.73). Taken together, our experiments definitely verified that enhanced therapeutic effects through liposomal formulations of anticancer agents depend on tumor accumulation of liposomes. Tumor accumulation of the radiolabeled liposomes evaluated by SPECT/CT imaging is applicable to appropriately determine indications for liposomal antitumor agents.
Assuntos
Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/análogos & derivados , Neoplasias Ovarianas/diagnóstico por imagem , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Feminino , Humanos , Radioisótopos de Índio/farmacocinética , Lipossomos , Camundongos , Camundongos Nus , Polietilenoglicóis/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Inhibition of tumor angiogenesis by blockading the vascular endothelial growth factor (VEGF) signaling pathway is a promising therapeutic strategy for thyroid cancer. Lenvatinib mesilate (lenvatinib) is a potent inhibitor of VEGF receptors (VEGFR1-3) and other prooncogenic and prooncogenic receptor tyrosine kinases, including fibroblast growth factor receptors (FGFR1-4), platelet derived growth factor receptor α (PDGFRα), KIT, and RET. We examined the antitumor activity of lenvatinib against human thyroid cancer xenograft models in nude mice. Orally administered lenvatinib showed significant antitumor activity in 5 differentiated thyroid cancer (DTC), 5 anaplastic thyroid cancer (ATC), and 1 medullary thyroid cancer (MTC) xenograft models. Lenvatinib also showed antiangiogenesis activity against 5 DTC and 5 ATC xenografts, while lenvatinib showed in vitro antiproliferative activity against only 2 of 11 thyroid cancer cell lines: that is, RO82-W-1 and TT cells. Western blot analysis showed that cultured RO82-W-1 cells overexpressed FGFR1 and that lenvatinib inhibited the phosphorylation of FGFR1 and its downstream effector FRS2. Lenvatinib also inhibited the phosphorylation of RET with the activated mutation C634W in TT cells. These data demonstrate that lenvatinib provides antitumor activity mainly via angiogenesis inhibition but also inhibits FGFR and RET signaling pathway in preclinical human thyroid cancer models.
RESUMO
The antitumor activity of pladienolide B, a novel splicing inhibitor, against gastric cancer is totally unknown and no predictive biomarker of pladienolide B efficacy has been reported. We investigated the antitumor activity of pladienolide B and its derivative on gastric cancer cell lines and primary cultured cancer cells from carcinomatous ascites of gastric cancer patients. The effect of pladienolide B and its derivative on six gastric cancer cell lines was investigated using a MTT assay and the mean IC50 values determined to be 1.6 ± 1.2 (range, 0.6-4.0) and 1.2 ± 1.1 (range, 0.4-3.4) nM, respectively, suggesting strong antitumor activity against gastric cancer. The mean IC50 value of pladienolide B derivative against primary cultured cells from 12 gastric cancer patients was 4.9 ± 4.7 nM, indicative of high antitumor activity. When 18 SCID mice xenografted with primary cultured cells from three patients were administered the pladienolide B derivative intraperitoneally, all tumors completely disappeared within 2 weeks after treatment. Histological examination revealed a pathological complete response for all tumors. In the xenograft tumors after treatment with pladienolide B derivative, immature mRNA were detected and apoptotic cells were observed. When the expressions of cell-cycle proteins p16 and cyclin E in biopsied gastric cancer specimens were examined using immunohisctochemistry, positivities for p16 and cyclin E were significantly and marginally higher, respectively, in the low-IC50 group compared with the high-IC50 group, suggesting the possibility that they might be useful as predictive biomarkers for pladienolide B. In conclusion, pladienolide B was very active against gastric cancer via a mechanism involving splicing impairment and apoptosis induction.
Assuntos
Antineoplásicos/uso terapêutico , Compostos de Epóxi/uso terapêutico , Macrolídeos/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Ciclina E/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Splicing de RNA/efeitos dos fármacos , Splicing de RNA/genética , Distribuição Aleatória , Neoplasias Gástricas/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Many clinical cases of acquired resistance to the BRAF inhibitor vemurafenib have recently been reported. One of the causes of this acquired resistance is the BRAF downstream kinase point mutation MEK1-C121S. This mutation confers resistance to not only vemurafenib, but also to the allosteric MEK inhibitor selumetinib (AZD6244). Here, we investigated the pharmacologic activities and effectiveness of the novel MEK inhibitor E6201 against BRAF (v-raf murine sarcoma viral oncogene homolog B1)-V600E mutant melanoma harboring the MEK1-C121S mutation. A cell-free assay confirmed that E6201 is an ATP-competitive MEK inhibitor, meaning it has a different binding mode with MEK compared with allosteric MEK inhibitors. E6201 is more effective against BRAF-V600E mutant melanoma compared with BRAF wild-type melanoma based on MEK inhibition. We found that the acquired MEK1-C121S mutation in BRAF-V600E mutant melanoma conferred resistance to both vemurafenib and selumetinib but not E6201. The effectiveness of E6201 in this preclinical study is a result of its binding with MEK1 far from the C121S point mutation so the mutation is unable to influence the MAPK pathway inhibitory activity. These results support further clinical investigation of E6201.
Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Indóis/farmacologia , Lactonas/farmacologia , MAP Quinase Quinase 1/genética , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Sulfonamidas/farmacologia , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Indóis/uso terapêutico , Lactonas/uso terapêutico , MAP Quinase Quinase 1/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/genética , Mutagênese Sítio-Dirigida , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas/uso terapêutico , VemurafenibRESUMO
RET gene fusions are recurrent oncogenes identified in thyroid and lung carcinomas. Lenvatinib is a multi-tyrosine kinase inhibitor currently under evaluation in several clinical trials. Here we evaluated lenvatinib in RET gene fusion-driven preclinical models. In cellular assays, lenvatinib inhibited auto-phosphorylation of KIF5B-RET, CCDC6-RET, and NcoA4-RET. Lenvatinib suppressed the growth of CCDC6-RET human thyroid and lung cancer cell lines, and as well, suppressed anchorage-independent growth and tumorigenicity of RET gene fusion-transformed NIH3T3 cells. These results demonstrate that lenvatinib can exert antitumor activity against RET gene fusion-driven tumor models by inhibiting oncogenic RET gene fusion signaling.
Assuntos
Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Compostos de Fenilureia/farmacologia , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Quinolinas/farmacologia , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células NIH 3T3 , Transplante de Neoplasias , Neoplasias/enzimologia , Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Transdução de SinaisRESUMO
Pladienolide is a naturally occurring macrolide that binds to the SF3b complex to inhibit mRNA splicing. It has not been fully validated whether the splicing impairment is a relevant mechanism for the potent antitumor activity of pladienolide. We established pladienolide-resistant clones from WiDr and DLD1 colorectal cancer cells that were insensitive to the inhibitory action of pladienolide on cell proliferation and splicing. An mRNA-Seq differential analysis revealed that these two cell lines have an identical mutation at Arg1074 in the gene for SF3B1, which encodes a subunit of the SF3b complex. Reverse expression of the mutant protein transferred pladienolide resistance to WiDr cells. Furthermore, immunoprecipitation analysis using a radiolabeled probe showed that the mutation impaired the binding affinity of paldienolide to its target. These results clearly demonstrate that pladienolide exerts its potent activity by targeting SF3b and also suggest that inhibition of SF3b is a promising drug target for anticancer therapy.
Assuntos
Compostos de Epóxi/farmacologia , Macrolídeos/farmacologia , Fosfoproteínas/efeitos dos fármacos , Ribonucleoproteína Nuclear Pequena U2/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Compostos de Epóxi/metabolismo , Humanos , Macrolídeos/metabolismo , Fosfoproteínas/metabolismo , Splicing de RNA/efeitos dos fármacos , Fatores de Processamento de RNA , Ribonucleoproteína Nuclear Pequena U2/metabolismoRESUMO
Pladienolide is a naturally occurring antitumor macrolide that was discovered by using a cell-based reporter gene expression assay controlled by the human vascular endothelial growth factor promoter. Despite the unique mechanisms of action and prominent antitumor activities of pladienolides B and D in diverse in vitro and in vivo systems, their target protein has remained unclear. We used 3H-labeled, fluorescence-tagged and photoaffinity/biotin (PB)-tagged 'chemical probes' to identify a 140-kDa protein in splicing factor SF3b as the binding target of pladienolide. Immunoblotting of an enhanced green fluorescent protein fusion protein of SF3b subunit 3 (SAP130) revealed direct interaction between the PB probe and SAP130. The binding affinities of pladienolide derivatives to the SF3b complex were highly correlated with their inhibitory activities against reporter gene expression and cell proliferation. Furthermore, pladienolide B impaired in vivo splicing in a dose-dependent manner. Our results demonstrate that the SF3b complex is a pharmacologically relevant protein target of pladienolide and suggest that this splicing factor is a potential antitumor drug target.
Assuntos
Antineoplásicos/farmacologia , Compostos de Epóxi/farmacologia , Macrolídeos/farmacologia , Proteínas de Ligação a RNA/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Genes Reporter , Humanos , Ligação Proteica , Splicing de RNA/efeitos dos fármacos , Fatores de Processamento de RNA , Ribonucleoproteína Nuclear Pequena U2RESUMO
We have discovered seven novel 12-membered macrolides, pladienolides A to G, from Streptomyces platensis Mer-11107, with pladienolide B the most potently inhibiting hypoxia induced-VEGF expression and proliferation of the U251 cancer cell line. A growth inhibitory study using a 39-cell line drug-screening panel demonstrated that pladienolide B has strong antitumor activities in vitro. A COMPARE analysis reveals that it has a unique antitumor spectrum that sets it apart from anticancer drugs currently in clinical use. This result suggests that pladienolide B has a novel mechanism of action. A series of xenograft studies were conducted to evaluate the in vivo potency of pladienolides. Pladienolide B extensively inhibited tumor growth in xenograft models. In the most sensitive model, using BSY-1 xenografts, tumors were completely regressed by administration of pladienolide B. For the reason of their novel mechanism of action and excellent in vivo efficacy, pladienolides appear to have major potential for use in cancer treatment.