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1.
Development ; 150(10)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37254876

RESUMO

RAS/MAPK gene dysfunction underlies various cancers and neurocognitive disorders. Although the roles of RAS/MAPK genes have been well studied in cancer, less is known about their function during neurodevelopment. There are many genes that work in concert to regulate RAS/MAPK signaling, suggesting that if common brain phenotypes could be discovered they could have a broad impact on the many other disorders caused by distinct RAS/MAPK genes. We assessed the cellular and molecular consequences of hyperactivating the RAS/MAPK pathway using two distinct genes in a cell type previously implicated in RAS/MAPK-mediated cognitive changes, cortical GABAergic interneurons. We uncovered some GABAergic core programs that are commonly altered in each of the mutants. Notably, hyperactive RAS/MAPK mutants bias developing cortical interneurons towards those that are somatostatin positive. The increase in somatostatin-positive interneurons could also be prevented by pharmacological inhibition of the core RAS/MAPK signaling pathway. Overall, these findings present new insights into how different RAS/MAPK mutations can converge on GABAergic interneurons, which may be important for other RAS/MAPK genes and related disorders.


Assuntos
Transdução de Sinais , Somatostatina , Alelos , Somatostatina/genética , Somatostatina/metabolismo , Transdução de Sinais/genética , Sistema de Sinalização das MAP Quinases/genética , Interneurônios/metabolismo , Neurônios GABAérgicos/metabolismo
2.
Proc Natl Acad Sci U S A ; 117(11): 6189-6195, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123116

RESUMO

Neurofibromatosis 1 (NF1) is caused by mutations in the NF1 gene, which encodes the protein, neurofibromin, an inhibitor of Ras activity. Cortical GABAergic interneurons (CINs) are implicated in NF1 pathology, but the cellular and molecular changes to CINs are unknown. We deleted mouse Nf1 from the medial ganglionic eminence, which gives rise to both oligodendrocytes and CINs that express somatostatin and parvalbumin. Nf1 loss led to a persistence of immature oligodendrocytes that prevented later-generated oligodendrocytes from occupying the cortex. Moreover, molecular and cellular properties of parvalbumin (PV)-positive CINs were altered by the loss of Nf1, without changes in somatostatin (SST)-positive CINs. We discovered that loss of Nf1 results in a dose-dependent decrease in Lhx6 expression, the transcription factor necessary to establish SST+ and PV+ CINs, which was rescued by the MEK inhibitor SL327, revealing a mechanism whereby a neurofibromin/Ras/MEK pathway regulates a critical CIN developmental milestone.


Assuntos
Córtex Cerebral/patologia , Neurônios GABAérgicos/patologia , Interneurônios/patologia , Proteínas com Homeodomínio LIM/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurofibromatose 1/patologia , Neurofibromina 1/genética , Fatores de Transcrição/metabolismo , Aminoacetonitrila/administração & dosagem , Aminoacetonitrila/análogos & derivados , Animais , Células Cultivadas , Córtex Cerebral/citologia , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Neurônios GABAérgicos/metabolismo , Humanos , Interneurônios/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Eminência Mediana/citologia , Camundongos , Camundongos Knockout , Neurofibromatose 1/genética , Neurofibromina 1/metabolismo , Neuroglia/citologia , Parvalbuminas/metabolismo , Cultura Primária de Células , Somatostatina/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo
3.
Nanomedicine ; 21: 102072, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31376572

RESUMO

Exosomes are critical mediators of intercellular crosstalk and are regulator of the cellular/tumor microenvironment. Exosomes have great prospects for clinical application as a theranostic and prognostic probe. Nevertheless, the advancement of exosomes research has been thwarted by our limited knowledge of the most efficient isolation method and their in vivo trafficking. Here we have shown that a combination of two size-based methods using a 0.20 µm syringe filter and 100 k centrifuge membrane filter followed by ultracentrifugation yields a greater number of uniform exosomes. We also demonstrated the visual representation and quantification of the differential in vivo distribution of radioisotope 131I-labeled exosomes from diverse cellular origins, e.g., tumor cells with or without treatments, myeloid-derived suppressor cells and endothelial progenitor cells. We also determined that the distribution was dependent on the exosomal protein/cytokine contents. The applied in vivo imaging modalities can be utilized to monitor disease progression, metastasis, and exosome-based targeted therapy.


Assuntos
Exossomos/transplante , Radioisótopos do Iodo , Marcação por Isótopo , Nanomedicina Teranóstica , Animais , Linhagem Celular , Radioisótopos do Iodo/química , Radioisótopos do Iodo/farmacocinética , Radioisótopos do Iodo/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos
4.
Int J Mol Sci ; 18(12)2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29292756

RESUMO

Metastatic breast cancer (BC) (also referred to as stage IV) spreads beyond the breast to the bones, lungs, liver, or brain and is a major contributor to the deaths of cancer patients. Interestingly, metastasis is a result of stroma-coordinated hallmarks such as invasion and migration of the tumor cells from the primary niche, regrowth of the invading tumor cells in the distant organs, proliferation, vascularization, and immune suppression. Targeted therapies, when used as monotherapies or combination therapies, have shown limited success in decreasing the established metastatic growth and improving survival. Thus, novel therapeutic targets are warranted to improve the metastasis outcomes. We have been actively investigating the cytochrome P450 4 (CYP4) family of enzymes that can biosynthesize 20-hydroxyeicosatetraenoic acid (20-HETE), an important signaling eicosanoid involved in the regulation of vascular tone and angiogenesis. We have shown that 20-HETE can activate several intracellular protein kinases, pro-inflammatory mediators, and chemokines in cancer. This review article is focused on understanding the role of the arachidonic acid metabolic pathway in BC metastasis with an emphasis on 20-HETE as a novel therapeutic target to decrease BC metastasis. We have discussed all the significant investigational mechanisms and put forward studies showing how 20-HETE can promote angiogenesis and metastasis, and how its inhibition could affect the metastatic niches. Potential adjuvant therapies targeting the tumor microenvironment showing anti-tumor properties against BC and its lung metastasis are discussed at the end. This review will highlight the importance of exploring tumor-inherent and stromal-inherent metabolic pathways in the development of novel therapeutics for treating BC metastasis.


Assuntos
Ácido Araquidônico/genética , Neoplasias da Mama/tratamento farmacológico , Família 4 do Citocromo P450/genética , Terapia de Alvo Molecular , Ácido Araquidônico/antagonistas & inibidores , Ácido Araquidônico/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Ácidos Hidroxieicosatetraenoicos/biossíntese , Ácidos Hidroxieicosatetraenoicos/genética , Metástase Neoplásica , Transdução de Sinais , Microambiente Tumoral/genética
5.
Int J Mol Sci ; 18(12)2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29258180

RESUMO

Glioblastoma (GBM) is considered one of the most malignant, genetically heterogeneous, and therapy-resistant solid tumor. Therapeutic options are limited in GBM and involve surgical resection followed by chemotherapy and/or radiotherapy. Adjuvant therapies, including antiangiogenic treatments (AATs) targeting the VEGF-VEGFR pathway, have witnessed enhanced infiltration of bone marrow-derived myeloid cells, causing therapy resistance and tumor relapse in clinics and in preclinical models of GBM. This review article is focused on gathering previous clinical and preclinical reports featuring major challenges and lessons in GBM. Potential combination therapies targeting the tumor microenvironment (TME) to overcome the myeloid cell-mediated resistance problem in GBM are discussed. Future directions are focused on the use of TME-directed therapies in combination with standard therapy in clinical trials, and the exploration of novel therapies and GBM models for preclinical studies. We believe this review will guide the future of GBM research and therapy.


Assuntos
Glioblastoma/metabolismo , Glioblastoma/patologia , Inibidores da Angiogênese/uso terapêutico , Glioblastoma/tratamento farmacológico , Humanos , Células Mieloides/metabolismo , Células Mieloides/patologia , Neovascularização Patológica , Microambiente Tumoral
6.
JCO Precis Oncol ; 7: e2300088, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37677121

RESUMO

PURPOSE: Recurrent gene mutations in speckle-type POZ protein (SPOP), the substrate-binding component of E3 ubiquitin ligase, are associated with tumor progression in prostate and endometrial cancers. Here, we characterized SPOP mutations in these cancers and explored their association with molecular and immune signatures and patient outcomes. METHODS: There were 7,398 prostate cancer and 19,188 endometrial cancer samples analyzed for clinical and molecular profiles at Caris Life Sciences. Overall survival (OS) was analyzed using Kaplan-Meier survival curves. Statistical significance was determined using chi-square and Mann-Whitney U tests, with P values adjusted for multiple comparisons. RESULTS: SPOP mutations were identified in 9.2% of prostate and 4.3% of endometrial cancers. Mutations clustered in the SPOP meprin and TRAF-C homology domain, with no significant overlap between cancer types. SPOP mutation was associated with differential comutation profiles and opposing tumor immune microenvironment signatures for each cancer, with greater immune infiltration in SPOP-mutated endometrial cancer. SPOP-mutated prostate and endometrial cancers displayed altered epigenetic gene expression, including opposite regulation of BRD2 transcripts. In SPOP-mutant prostate cancer, higher expression of androgen receptor-regulated transcripts and improved OS after treatment with hormonal agents were observed. In endometrial cancer, hormone receptor expression was significantly lower in SPOP-mutated tumors and differences in OS were highly dependent on the particular hotspot mutation and histologic subtype. CONCLUSION: These data indicate that SPOP mutations drive opposing molecular and immune landscapes in prostate and endometrial cancers-suggesting a loss-of-function mechanism in prostate cancer and gain-of-function mechanism in endometrial cancer-and provide a rationale for tailored therapeutic approaches.


Assuntos
Neoplasias do Endométrio , Neoplasias da Próstata , Masculino , Feminino , Humanos , Próstata , Fatores de Transcrição , Neoplasias do Endométrio/genética , Neoplasias da Próstata/genética , Mutação/genética , Microambiente Tumoral
7.
PLoS One ; 16(2): e0246646, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33544755

RESUMO

Glioblastoma (GBM) is a hypervascular and aggressive primary malignant tumor of the central nervous system. Recent investigations showed that traditional therapies along with antiangiogenic therapies failed due to the development of post-therapy resistance and recurrence. Previous investigations showed that there were changes in the cellular and metabolic compositions in the tumor microenvironment (TME). It can be said that tumor cell-directed therapies are ineffective and rethinking is needed how to treat GBM. It is hypothesized that the composition of TME-associated cells will be different based on the therapy and therapeutic agents, and TME-targeting therapy will be better to decrease recurrence and improve survival. Therefore, the purpose of this study is to determine the changes in the TME in respect of T-cell population, M1 and M2 macrophage polarization status, and MDSC population following different treatments in a syngeneic model of GBM. In addition to these parameters, tumor growth and survival were also studied following different treatments. The results showed that changes in the TME-associated cells were dependent on the therapeutic agents, and the TME-targeting therapy improved the survival of the GBM bearing animals. The current GBM therapies should be revisited to add agents to prevent the accumulation of bone marrow-derived cells in the TME or to prevent the effect of immune-suppressive myeloid cells in causing alternative neovascularization, the revival of glioma stem cells, and recurrence. Instead of concurrent therapy, a sequential strategy would be better to target TME-associated cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Imunoterapia/métodos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Células Mieloides/patologia , Projetos Piloto , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
8.
Elife ; 102021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33666173

RESUMO

In utero exposure to maternal immune activation (MIA) is an environmental risk factor for neurodevelopmental and neuropsychiatric disorders. Animal models provide an opportunity to identify mechanisms driving neuropathology associated with MIA. We performed time-course transcriptional profiling of mouse cortical development following induced MIA via poly(I:C) injection at E12.5. MIA-driven transcriptional changes were validated via protein analysis, and parallel perturbations to cortical neuroanatomy were identified via imaging. MIA-induced acute upregulation of genes associated with hypoxia, immune signaling, and angiogenesis, by 6 hr following exposure. This acute response was followed by changes in proliferation, neuronal and glial specification, and cortical lamination that emerged at E14.5 and peaked at E17.5. Decreased numbers of proliferative cells in germinal zones and alterations in neuronal and glial populations were identified in the MIA-exposed cortex. Overall, paired transcriptomic and neuroanatomical characterization revealed a sequence of perturbations to corticogenesis driven by mid-gestational MIA.


Assuntos
Encéfalo/embriologia , Neurogênese , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Camundongos Endogâmicos C57BL , Transtornos do Neurodesenvolvimento , Poli I-C/imunologia , Gravidez , Transcriptoma
9.
Front Mol Neurosci ; 13: 573409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33071758

RESUMO

The TSC1 and TSC2 genes are connected to multiple syndromes from Tuberous Sclerosis Complex (TSC) to autism spectrum disorder (ASD), with uncertainty if genetic variants cause all or subsets of phenotypes based on the location and type of change. For TSC1, few have addressed if non-TSC associated genetic variants have direct contributions to changes in neurological genotype-to-phenotype impacts, including elevated rates of ASD and seizures. Dominant variants cause TSC, yet TSC1 has many heritable variants not dominant for TSC that are poorly understood in neurological function, with some associated with ASD. Herein, we examined how missense variants in TSC1, R336W, T360N, T393I, S403L, and H732Y, impacted the development of cortical inhibitory interneurons, cell-types whose molecular, cellular, and physiological properties are altered after the loss of mouse TSC1. We found these variants complemented a known phenotype caused by loss of TSC1, increased cell size. However, distinct variants, particularly S403L showed deficits in complementing an increase in parvalbumin levels and exhibited smaller amplitude after hyperpolarizations. Overall, these data show that subtle phenotypes can be induced by some TSC1 missense variants and provide an in vivo system to assess TSC1 variants' neurological impact better.

10.
Cancer Lett ; 476: 57-66, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32061755

RESUMO

Targeting early lesion in breast cancer is more therapeutically effective. We have previously identified an oncoprotein GT198 (PSMC3IP) in human breast cancer. Here we investigated GT198 in MMTV-PyMT mouse mammary gland tumors and found that GT198 is a shared early lesion in both species. Similar to human breast cancer even before a tumor appears, cytoplasmic GT198 is overexpressed in mouse tumor stroma including pericyte stem cells, descendent adipocytes, fibroblasts, and myoepithelial cells. Using recombinant GT198 protein as an antigen, we vaccinated MMTV-PyMT mice and found that the GT198 vaccine delayed mouse tumor growth and reduced lung metastasis. The antitumor effects were linearly correlated with vaccinated mouse serum titers of GT198 antibody, which recognized cell surface GT198 protein on viable tumor cells confirmed by FACS. Furthermore, GT198+ tumor cells isolated from MMTV-PyMT tumor induced faster tumor growths than GT198- cells when re-implanted into normal FVB/N mice. Together, this first study of GT198 vaccine in mouse showed its effectiveness in antitumor and anti-metastasis. The finding supports GT198 as a potential target in human immunotherapy since GT198 defect is shared in both human and mouse.


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Vacinas Anticâncer/administração & dosagem , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/prevenção & controle , Proteínas Nucleares/imunologia , Transativadores/imunologia , Vacinação/métodos , Animais , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos , Proteínas Nucleares/antagonistas & inibidores , Transativadores/antagonistas & inibidores
11.
Nat Commun ; 10(1): 4994, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676823

RESUMO

Medial ganglionic eminence (MGE)-derived somatostatin (SST)+ and parvalbumin (PV)+ cortical interneurons (CINs), have characteristic molecular, anatomical and physiological properties. However, mechanisms regulating their diversity remain poorly understood. Here, we show that conditional loss of the Tuberous Sclerosis Complex (TSC) gene, Tsc1, which inhibits the mammalian target of rapamycin (MTOR), causes a subset of SST+ CINs, to express PV and adopt fast-spiking (FS) properties, characteristic of PV+ CINs. Milder intermediate phenotypes also occur when only one allele of Tsc1 is deleted. Notably, treatment of adult mice with rapamycin, which inhibits MTOR, reverses the phenotypes. These data reveal novel functions of MTOR signaling in regulating PV expression and FS properties, which may contribute to TSC neuropsychiatric symptoms. Moreover, they suggest that CINs can exhibit properties intermediate between those classically associated with PV+ or SST+ CINs, which may be dynamically regulated by the MTOR signaling.


Assuntos
Córtex Cerebral/fisiologia , Interneurônios/fisiologia , Parvalbuminas/metabolismo , Somatostatina/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Potenciais de Ação/fisiologia , Animais , Córtex Cerebral/citologia , Feminino , Interneurônios/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Parvalbuminas/genética , Técnicas de Patch-Clamp , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Somatostatina/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética
12.
Neoplasia ; 20(10): 1070-1082, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30236892

RESUMO

BACKGROUND: Glioblastoma (GBM) was shown to relapse faster and displayed therapeutic resistance to antiangiogenic therapies (AATs) through an alternative tumor cell-driven mechanism of neovascularization called vascular mimicry (VM). We identified highly upregulated interleukin 8 (IL-8)-CXCR2 axis in tumor cells in high-grade human glioma and AAT-treated orthotopic GBM tumors. METHODS: Human GBM tissue sections and tissue array were used to ascertain the clinical relevance of CXCR2-positive tumor cells in the formation of VM. We utilized U251 and U87 human tumor cells to understand VM in an orthotopic GBM model and AAT-mediated enhancement in VM was modeled using vatalanib (anti-VEGFR2) and avastin (anti-VEGF). Later, VM was inhibited by SB225002 (CXCR2 inhibitor) in a preclinical study. RESULTS: Overexpression of IL8 and CXCR2 in human datasets and histological analysis was identified as a bonafide candidate to validate VM through in vitro and animal model studies. AAT-treated tumors displayed a higher number of CXCR2-positive GBM-stem cells with endothelial-like phenotypes. Stable knockdown of CXCR2 expression in tumor cells led to decreased tumor growth as well as incomplete VM structures in the animal models. Similar data were obtained following SB225002 treatment. CONCLUSIONS: The present study suggests that tumor cell autonomous IL-8-CXCR2 pathway is instrumental in AAT-mediated resistance and VM formation in GBM. Therefore, CXCR2 can be targeted through SB225002 and can be combined with standard therapies to improve the therapeutic outcomes in clinical trials.


Assuntos
Inibidores da Angiogênese/farmacologia , Neoplasias Encefálicas/irrigação sanguínea , Glioblastoma/irrigação sanguínea , Receptores de Interleucina-8B/metabolismo , Animais , Bevacizumab/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Humanos , Interleucina-8/metabolismo , Terapia de Alvo Molecular/métodos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Compostos de Fenilureia/farmacologia , Ftalazinas/farmacologia , Piridinas/farmacologia , Ratos Nus , Receptores de Interleucina-8B/genética , Análise Serial de Tecidos , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Transl Oncol ; 10(4): 650-660, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28668763

RESUMO

Glioblastoma (GBM) is a hypervascular neoplasia of the central nervous system with an extremely high rate of mortality. Owing to its hypervascularity, anti-angiogenic therapies (AAT) have been used as an adjuvant to the traditional surgical resection, chemotherapy, and radiation. The benefits of AAT have been transient and the tumors were shown to relapse faster and demonstrated particularly high rates of AAT therapy resistance. Alternative neovascularization mechanisms were shown to be at work in these resilient tumors to counter the AAT therapy insult. Vascular Mimicry (VM) is the uncanny ability of tumor cells to acquire endothelial-like properties and lay down vascular patterned networks reminiscent of host endothelial blood vessels. The VM channels served as an irrigation system for the tumors to meet with the increasing metabolic and nutrient demands of the tumor in the event of the ensuing hypoxia resulting from AAT. In our previous studies, we have demonstrated that AAT accelerates VM in GBM. In this review, we will focus on the origins of VM, visualizing VM in AAT-treated tumors and the development of VM as a resistance mechanism to AAT.

14.
Oncotarget ; 8(31): 51591-51607, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881671

RESUMO

Angiogenesis promotes tumor development. Understanding the crucial factors regulating tumor angiogenesis may reveal new therapeutic targets. Human GT198 (PSMC3IP or Hop2) is an oncoprotein encoded by a DNA repair gene that is overexpressed in tumor stromal vasculature to stimulate the expression of angiogenic factors. Here we show that pericytes expressing GT198 give rise to tumor cells through angiogenesis. GT198+ pericytes and perivascular cells are commonly present in the stromal compartment of various human solid tumors and rodent xenograft tumor models. In human oral cancer, GT198+ pericytes proliferate into GT198+ tumor cells, which migrate into lymph nodes. Increased GT198 expression is associated with increased lymph node metastasis and decreased progression-free survival in oral cancer patients. In rat brain U-251 glioblastoma xenografts, GT198+ pericytes of human tumor origin encase endothelial cells of rat origin to form mosaic angiogenic blood vessels, and differentiate into pericyte-derived tumor cells. The net effect is continued production of glioblastoma tumor cells from malignant pericytes via angiogenesis. In addition, activation of GT198 induces the expression of VEGF and promotes tube formation in cultured U251 cells. Furthermore, vaccination using GT198 protein as an antigen in mouse xenograft of GL261 glioma delayed tumor growth and prolonged mouse survival. Together, these findings suggest that GT198-expressing malignant pericytes can give rise to tumor cells through angiogenesis, and serve as a potential source of cells for distant metastasis. Hence, the oncoprotein GT198 has the potential to be a new target in anti-angiogenic therapies in human cancer.

15.
PLoS One ; 12(6): e0178830, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28609459

RESUMO

Distant metastasis is the primary cause of death in the majority of the cancer types. Recently, much importance has been given to tumor microenvironment (TME) in the development of invasive malignant tumors, as well as the metastasis potential. The ability of tumor cells to modulate TME and to escape immune-mediated attack by releasing immunosuppressive cytokines has become a hallmark of breast cancer. Our study shows the effect of IV formulation of HET0016 (HPßCD-HET0016) a selective inhibitor of 20-HETE synthesis, administered intravenously in immune-competent in vivo mouse model of murine breast cancer. 4T1 luciferase positive cells were implanted to the mammary fat pad in Balb/c mice. Treatment started on day 15, and was administered for 5 days a week for 3 weeks. The development of metastasis was detected via optical imaging. Blood, spleen, lungs, bone marrow and tumor were collected for flow cytometry, to investigate changes in myeloid-derived suppressive cells (MDSCs) populations and endothelial phenotype. Tumor and lungs were collected for protein analysis. Our results show that HPßCD-HET0016: (1) decreased tumor volume and lung metastasis compared to the vehicle group; (2) reduced migration and invasion of tumor cells and levels of metalloproteinases in the lungs of animals treated with HPßCD-HET0016 via PI3K/AKT pathway; and (3) decreased expression of pro-inflammatory cytokines, growth factors and granulocytic MDSCs population in the lung microenvironment in treated animals. Thus, HPßCD-HET0016 showed potential in treating lung metastasis in a preclinical mouse model and needs further investigations on TME.


Assuntos
Amidinas/farmacologia , Modelos Animais de Doenças , Imunocompetência , Neoplasias Pulmonares/prevenção & controle , Neoplasias Mamárias Experimentais/tratamento farmacológico , Administração Intravenosa , Amidinas/administração & dosagem , Animais , Western Blotting , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Citocinas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
16.
Histol Histopathol ; 32(9): 917-928, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27990624

RESUMO

Glioblastoma (GBM) is one hypervascular and hypoxic tumor known among solid tumors. Antiangiogenic therapeutics (AATs) have been tested as an adjuvant to normalize blood vessels and control abnormal vasculature. Evidence of relapse exemplified in the progressive tumor growth following AAT reflects development of resistance to AATs. Here, we identified that GBM following AAT (Vatalanib) acquired an alternate mechanism to support tumor growth, called vascular mimicry (VM). We observed that Vatalanib induced VM vessels are positive for periodic acid-Schiff (PAS) matrix but devoid of any endothelium on the inner side and lined by tumor cells on the outer-side. The PAS+ matrix is positive for basal laminae (laminin) indicating vascular structures. Vatalanib treated GBM displayed various stages of VM such as initiation (mosaic), sustenance, and full-blown VM. Mature VM structures contain red blood cells (RBC) and bear semblance to the functional blood vessel-like structures, which provide all growth factors to favor tumor growth. Vatalanib treatment significantly increased VM especially in the core of the tumor, where HIF-1α was highly expressed in tumor cells. VM vessels correlate with hypoxia and are characterized by co-localized MHC-1+ tumor and HIF-1α expression. Interestingly, 20-HETE synthesis inhibitor HET0016 significantly decreased GBM tumors through decreasing VM structures both at the core and at periphery of the tumors. In summary, AAT induced resistance characterized by VM is an alternative mechanism adopted by tumors to make functional vessels by transdifferentiation of tumor cells into endothelial-like cells to supply nutrients in the event of hypoxia. AAT induced VM is a potential therapeutic target of the novel formulation of HET0016. Our present study suggests that HET0016 has a potential to target therapeutic resistance and can be combined with other antitumor agents in preclinical and clinical trials.


Assuntos
Amidinas/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Neovascularização Patológica/patologia , Ftalazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Amidinas/administração & dosagem , Inibidores da Angiogênese/administração & dosagem , Animais , Linhagem Celular Tumoral , Glioblastoma/tratamento farmacológico , Humanos , Ftalazinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Piridinas/administração & dosagem , Ratos , Ratos Nus
17.
Sci Rep ; 7(1): 13754, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29062041

RESUMO

Tumor development and therapeutic resistance are linked with tumor-associated macrophage (TAM) and myeloid-derived suppressor cell (MDSC) infiltration in tumors via chemokine axis. Chemokine expression, which determines the pro or anti-inflammatory status of myeloid cells, are partly regulated by the nuclear factor-kappa B (NF-κB) pathway. Here, we identified that conditional deletion of canonical NF-κB signaling (p65) in myeloid cells inhibited syngeneic glioblastoma (GBM) through decreased CD45 infiltration in tumors, as characterized by decreased TAMs (CD206+) and MDSCs (Gr1+ CD11b+), increased dendritic cells (CD86+) and cytotoxic T cells (CD8+) in the p65 knockout (KO) mice. Proinflammatory cytokines (IFNγ, MCP1, MIP1α, and TNFα) and myeloid differentiation factor (Endoglin) were increased in myeloid cells from p65 KO tumor, which demonstrated an influence on CD8+T cell proliferation. In contrast, p65KO athymic chimeric mice with human GBM, failed to inhibit tumor growth, confirming the contribution of T cells in an immune competent model. The analysis of human datasets and GBM tumors revealed higher expression of p65 in GBM-associated CD68+ macrophages compared to neighboring stroma. Thus, canonical NF-κB signaling has an anti-inflammatory role and is required for macrophage polarization, immune suppression, and GBM growth. Combining an NF-κB inhibitor with standard therapy could improve antitumor immunity in GBM.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Células Mieloides/patologia , NF-kappa B/fisiologia , Animais , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Feminino , Glioblastoma/imunologia , Glioblastoma/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Células Mieloides/imunologia , Células Mieloides/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Sci Rep ; 7: 41809, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139732

RESUMO

Glioblastoma (GBM) is a hypervascular primary brain tumor with poor prognosis. HET0016 is a selective CYP450 inhibitor, which has been shown to inhibit angiogenesis and tumor growth. Therefore, to explore novel treatments, we have generated an improved intravenous (IV) formulation of HET0016 with HPßCD and tested in animal models of human and syngeneic GBM. Administration of a single IV dose resulted in 7-fold higher levels of HET0016 in plasma and 3.6-fold higher levels in tumor at 60 min than that in IP route. IV treatment with HPßCD-HET0016 decreased tumor growth, and altered vascular kinetics in early and late treatment groups (p < 0.05). Similar growth inhibition was observed in syngeneic GL261 GBM (p < 0.05). Survival studies using patient derived xenografts of GBM811, showed prolonged survival to 26 weeks in animals treated with focal radiation, in combination with HET0016 and TMZ (p < 0.05). We observed reduced expression of markers of cell proliferation (Ki-67), decreased neovascularization (laminin and αSMA), in addition to inflammation and angiogenesis markers in the treatment group (p < 0.05). Our results indicate that HPßCD-HET0016 is effective in inhibiting tumor growth through decreasing proliferation, and neovascularization. Furthermore, HPßCD-HET0016 significantly prolonged survival in PDX GBM811 model.


Assuntos
Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Glioblastoma/metabolismo , Glioblastoma/patologia , Actinas/metabolismo , Administração Intravenosa , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Modelos Animais de Doenças , Glioblastoma/tratamento farmacológico , Glioblastoma/mortalidade , Humanos , Neovascularização Patológica/tratamento farmacológico , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
J Cancer Sci Ther ; 8(7): 172-178, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28149448

RESUMO

OBJECTIVE: Anti-angiogenic therapies (AATs), targeting VEGF-VEGFR pathways, are being used as an adjuvant to normalize glioblastoma (GBM) vasculature. Unexpectedly, clinical trials have witnessed transient therapeutic effect followed by aggressive tumor recurrence. In pre-clinical studies, targeting VEGFR2 with vatalanib, increased GBM growth under hypoxic microenvironment. There is limited understanding of these unanticipated results. Here, we investigated tumor cell associated phenotypes in response to VEGFR2 blockade. METHODS: Human U251 cells were orthotopically implanted in mice (day 0) and were treated with vehicle or vatalanib on day 8. Tumor specimens were collected for immunohistochemistry and protein array. Nuclear translocation of VEGFR2 was analyzed through IHC and western blot. In vitro studies were performed in U251 (p53 and EGFR mutated) and U87 (p53 and EGFR wildtype) cells following vehicle or vatalanib treatments under normoxia (21% O2) and hypoxia (1% O2). Proliferation, cell cycle and apoptosis assays were done to analyze tumor cell phenotypes after treatments. RESULTS: Vatalanib treated animals displayed distinct patterns of VEGFR2 translocation into nuclear compartment of U251 tumor cells. In vitro studies suggest that vatalanib significantly induced nuclear translocation of VEGFR2, characterized in chromatin bound fraction, especially in U251 tumor cells grown under normoxia and hypoxia. Anti-VEGFR2 driven nuclear translocation of VEGFR2 was associated with increased cell cycle and proliferation, decreased apoptosis, and displayed increased invasiveness in U251 compared to U87 cells. CONCLUSIONS: Study suggests that AAT- induced molecular and phenotypic alterations in tumor cells are associated with mutation status and are responsible for aggressive tumor growth. Therefore, mutation status of the tumor in GBM patients should be taken in to consideration before applying targeted therapy to overcome unwanted effects.

20.
Cancer Lett ; 369(2): 416-26, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26404753

RESUMO

Glioblastoma (GBM) is a hypervascular and malignant form of brain tumors. Anti-angiogenic therapies (AAT) were used as an adjuvant against VEGF-VEGFR pathway to normalize blood vessels in clinical and preclinical studies, which resulted into marked hypoxia and recruited bone marrow derived cells (BMDCs) to the tumor microenvironment (TME). In vivo animal models to track BMDCs and investigate molecular mechanisms in AAT resistance are rare. We exploited recently established chimeric mouse to develop orthotopic U251 tumor, which uses as low as 5 × 10(6) GFP+ BM cells in athymic nude mice and engrafted >70% GFP+ cells within 14 days. Our unpublished data and published studies have indicated the involvement of immunosuppressive myeloid cells in therapeutic resistance in glioma. Similarly, in the present study, vatalanib significantly increased CD68+ myeloid cells, and CD133+, CD34+ and Tie2+ endothelial cell signatures. Therefore, we tested inhibition of CSF1R+ myeloid cells using GW2580 that reduced tumor growth by decreasing myeloid (Gr1+ CD11b+ and F4/80+) and angiogenic (CD202b+ and VEGFR2+) cell signatures in TME. CSF1R blockade significantly decreased inflammatory, proangiogenic and immunosuppressive molecular signatures compared to vehicle, vatalanib or combination. TCK1 or CXCL7, a potent chemoattractant and activator of neutrophils, was observed as most significantly decreased cytokine in CSF1R blockade. ERK MAPK pathway was involved in cytokine network regulation. In conclusion, present study confirmed the contribution of myeloid cells in GBM development and therapeutic resistance using chimeric mouse model. We identified novel molecular networks including CXCL7 chemokine as a promising target for future studies. Nonetheless, survival studies are required to assess the beneficial effect of CSF1R blockade.


Assuntos
Neoplasias Encefálicas/genética , Glioblastoma/genética , Células Mieloides/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Camundongos , Microambiente Tumoral
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