Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Mol Cell ; 81(21): 4481-4492.e9, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34555356

RESUMO

The etiological role of NSD2 enzymatic activity in solid tumors is unclear. Here we show that NSD2, via H3K36me2 catalysis, cooperates with oncogenic KRAS signaling to drive lung adenocarcinoma (LUAD) pathogenesis. In vivo expression of NSD2E1099K, a hyperactive variant detected in individuals with LUAD, rapidly accelerates malignant tumor progression while decreasing survival in KRAS-driven LUAD mouse models. Pathologic H3K36me2 generation by NSD2 amplifies transcriptional output of KRAS and several complementary oncogenic gene expression programs. We establish a versatile in vivo CRISPRi-based system to test gene functions in LUAD and find that NSD2 loss strongly attenuates tumor progression. NSD2 knockdown also blocks neoplastic growth of PDXs (patient-dervived xenografts) from primary LUAD. Finally, a treatment regimen combining NSD2 depletion with MEK1/2 inhibition causes nearly complete regression of LUAD tumors. Our work identifies NSD2 as a bona fide LUAD therapeutic target and suggests a pivotal epigenetic role of the NSD2-H3K36me2 axis in sustaining oncogenic signaling.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Metilação de DNA , Histona-Lisina N-Metiltransferase/química , Histonas/química , Neoplasias Pulmonares/metabolismo , Proteínas Repressoras/química , Adenocarcinoma de Pulmão/mortalidade , Animais , Biópsia , Sistemas CRISPR-Cas , Carcinogênese/genética , Progressão da Doença , Epigênese Genética , Epigenômica , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transplante de Neoplasias , Oncogenes , Prognóstico , Transdução de Sinais , Resultado do Tratamento
2.
BMC Biol ; 19(1): 107, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34030676

RESUMO

BACKGROUND: The anti-tumor activity of anti-PD-1/PD-L1 therapies correlates with T cell infiltration in tumors. Thus, a major goal in oncology is to find strategies that enhance T cell infiltration and efficacy of anti-PD-1/PD-L1 therapy. TGF-ß has been shown to contribute to T cell exclusion, and anti-TGF-ß improves anti-PD-L1 efficacy in vivo. However, TGF-ß inhibition has frequently been shown to induce toxicity in the clinic, and the clinical efficacy of combination PD-L1 and TGF-ß blockade has not yet been proven. To identify strategies to overcome resistance to PD-L1 blockade, the transcriptional programs associated with PD-L1 and/or TGF-ß blockade in the tumor microenvironment should be further elucidated. RESULTS: We used single-cell RNA sequencing in a mouse model to characterize the transcriptomic effects of PD-L1 and/or TGF-ß blockade on nearly 30,000 single cells in the tumor and surrounding microenvironment. Combination treatment led to upregulation of immune response genes, including multiple chemokine genes such as CCL5, in macrophages, and downregulation of extracellular matrix genes in fibroblasts. Analysis of publicly available tumor transcriptome profiles showed that the chemokine CCL5 was strongly associated with immune cell infiltration in various human cancers. Further investigation with in vivo models showed that intratumorally administered CCL5 enhanced cytotoxic lymphocytes and the anti-tumor activity of anti-PD-L1. CONCLUSIONS: Taken together, our data could be leveraged translationally to complement or find alternatives to anti-PD-L1 plus anti-TGF-ß combination therapy, for example through companion biomarkers, and/or to identify novel targets that could be modulated to overcome resistance.


Assuntos
Neoplasias , Animais , Antígeno B7-H1/genética , Camundongos , Transcriptoma , Fator de Crescimento Transformador beta , Microambiente Tumoral
3.
PLoS Genet ; 11(10): e1005525, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26439735

RESUMO

The cell cycle must be tightly coordinated for proper control of embryonic development and for the long-term maintenance of organs such as the lung. There is emerging evidence that Kinesin family member 7 (Kif7) promotes Hedgehog (Hh) signaling during embryonic development, and its misregulation contributes to diseases such as ciliopathies and cancer. Kif7 encodes a microtubule interacting protein that controls Hh signaling through regulation of microtubule dynamics within the primary cilium. However, whether Kif7 has a function in nonciliated cells remains largely unknown. The role Kif7 plays in basic cell biological processes like cell proliferation or cell cycle progression also remains to be elucidated. Here, we show that Kif7 is required for coordination of the cell cycle, and inactivation of this gene leads to increased cell proliferation in vivo and in vitro. Immunostaining and transmission electron microscopy experiments show that Kif7dda/dda mutant lungs are hyperproliferative and exhibit reduced alveolar epithelial cell differentiation. KIF7 depleted C3H10T1/2 fibroblasts and Kif7dda/dda mutant mouse embryonic fibroblasts have increased growth rates at high cellular densities, suggesting that Kif7 may function as a general regulator of cellular proliferation. We ascertained that in G1, Kif7 and microtubule dynamics regulate the expression and activity of several components of the cell cycle machinery known to control entry into S phase. Our data suggest that Kif7 may function to regulate the maintenance of the respiratory airway architecture by controlling cellular density, cell proliferation, and cycle exit through its role as a microtubule associated protein.


Assuntos
Proliferação de Células/genética , Desenvolvimento Embrionário/genética , Cinesinas/genética , Pulmão/crescimento & desenvolvimento , Animais , Cílios/genética , Cílios/fisiologia , Embrião de Mamíferos , Fibroblastos/metabolismo , Proteínas Hedgehog/genética , Cinesinas/metabolismo , Pulmão/metabolismo , Camundongos , Microtúbulos/genética , Microtúbulos/metabolismo , Ventilação Pulmonar , Transdução de Sinais/genética
4.
Dev Biol ; 407(1): 40-56, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26278035

RESUMO

The developing diaphragm consists of various differentiating cell types, many of which are not well characterized during organogenesis. One important but incompletely understood tissue, the diaphragmatic mesothelium, is distinctively present from early stages of development. Congenital Diaphragmatic Hernia (CDH) occurs in humans when diaphragm tissue is lost during development, resulting in high morbidity and mortality postnatally. We utilized a Wilms Tumor 1 (Wt1) mutant mouse model to investigate the involvement of the mesothelium in normal diaphragm signaling and development. Additionally, we developed and characterized a Wt1(CreERT2)-driven ß-catenin loss-of-function model of CDH after finding that canonical Wnt signaling and ß-catenin are reduced in Wt1 mutant mesothelium. Mice with ß-catenin loss or constitutive activation induced in the Wt1 lineage are only affected when tamoxifen injection occurs between E10.5 and E11.5, revealing a critical time-frame for Wt1/ ß-catenin activity. Conditional ß-catenin loss phenocopies the Wt1 mutant diaphragm defect, while constitutive activation of ß-catenin on the Wt1 mutant background is sufficient to close the diaphragm defect. Proliferation and apoptosis are affected, but primarily these genetic manipulations appear to lead to a change in normal diaphragm differentiation. Our data suggest a fundamental role for mesothelial signaling in proper formation of the diaphragm.


Assuntos
Diafragma/embriologia , Proteínas Repressoras/fisiologia , Transdução de Sinais , beta Catenina/fisiologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Hérnias Diafragmáticas Congênitas/etiologia , Humanos , Camundongos , Especificidade de Órgãos , Proteínas WT1
5.
Proc Natl Acad Sci U S A ; 110(21): E1898-905, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23650387

RESUMO

Congenital diaphragmatic hernia (CDH) is a common birth defect that results in a high degree of neonatal morbidity and mortality, but its pathological mechanisms are largely unknown. Therefore, we performed a forward genetic screen in mice to identify unique genes, models, and mechanisms of abnormal diaphragm development. We identified a mutant allele of kinesin family member 7 (Kif7), the disorganized diaphragm (dd). Embryos homozygous for the dd allele possess communicating diaphragmatic hernias, central tendon patterning defects, and increased cell proliferation with diaphragmatic tissue hyperplasia. Because the patterning of the central tendon is undescribed, we analyzed the expression of genes regulating tendonogenesis in dd/dd mutant embryos, and we determined that retinoic acid (RA) signaling was misregulautted. To further investigate the role of Kif7 and RA signaling in the development of the embryonic diaphragm, we established primary mesenchymal cultures of WT embryonic day 13.5 diaphragmatic cells. We determined that RA signaling is necessary for the expression of tendon markers as well as the expression of other CDH-associated genes. Knockdown of Kif7, and retinoic acid receptors alpha (Rara), beta (Rarb), and gamma (Rarg) indicated that RA signaling is dependent on these genes to promote tendonogenesis within the embryonic diaphragm. Taken together, our results provide evidence for a model in which inhibition of RA receptor signaling promotes CDH pathogenesis through a complex gene network.


Assuntos
Padronização Corporal , Diferenciação Celular , Diafragma/embriologia , Hérnias Diafragmáticas Congênitas , Cinesinas/metabolismo , Proteínas Musculares/metabolismo , Transdução de Sinais , Alelos , Animais , Linhagem Celular , Diafragma/patologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Hérnia Diafragmática/embriologia , Hérnia Diafragmática/genética , Hérnia Diafragmática/patologia , Cinesinas/genética , Camundongos , Camundongos Mutantes , Proteínas Musculares/genética , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Tendões/embriologia , Tendões/patologia , Tretinoína/metabolismo , Receptor gama de Ácido Retinoico
6.
Cell Rep ; 43(8): 114606, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39120974

RESUMO

Patients with small-cell lung cancer (SCLC) are in dire need of more effective therapeutic options. Frequent disruption of the G1 checkpoint in SCLC cells creates a dependency on the G2/M checkpoint to maintain genomic integrity. Indeed, in pre-clinical models, inhibiting the G2/M checkpoint kinase WEE1 shows promise in inhibiting SCLC growth. However, toxicity and acquired resistance limit the clinical effectiveness of this strategy. Here, using CRISPR-Cas9 knockout screens in vitro and in vivo, we identified multiple factors influencing the response of SCLC cells to the WEE1 kinase inhibitor AZD1775, including the GCN2 kinase and other members of its signaling pathway. Rapid activation of GCN2 upon AZD1775 treatment triggers a stress response in SCLC cells. Pharmacological or genetic activation of the GCN2 pathway enhances cancer cell killing by AZD1775. Thus, activation of the GCN2 pathway represents a promising strategy to increase the efficacy of WEE1 inhibitors in SCLC.


Assuntos
Proteínas de Ciclo Celular , Neoplasias Pulmonares , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases , Pirimidinonas , Carcinoma de Pequenas Células do Pulmão , Humanos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Linhagem Celular Tumoral , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Pirimidinonas/farmacologia , Pirimidinonas/uso terapêutico , Pirazóis/farmacologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Camundongos Nus
7.
Cell Rep ; 42(1): 111990, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36640300

RESUMO

Small cell lung cancer (SCLC) is a lethal form of lung cancer. Here, we develop a quantitative multiplexed approach on the basis of lentiviral barcoding with somatic CRISPR-Cas9-mediated genome editing to functionally investigate candidate regulators of tumor initiation and growth in genetically engineered mouse models of SCLC. We found that naphthalene pre-treatment enhances lentiviral vector-mediated SCLC initiation, enabling high multiplicity of tumor clones for analysis through high-throughput sequencing methods. Candidate drivers of SCLC identified from a meta-analysis across multiple human SCLC genomic datasets were tested using this approach, which defines both positive and detrimental impacts of inactivating 40 genes across candidate pathways on SCLC development. This analysis and subsequent validation in human SCLC cells establish TSC1 in the PI3K-AKT-mTOR pathway as a robust tumor suppressor in SCLC. This approach should illuminate drivers of SCLC, facilitate the development of precision therapies for defined SCLC genotypes, and identify therapeutic targets.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Camundongos , Animais , Humanos , Carcinoma de Pequenas Células do Pulmão/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Pulmonares/patologia , Genes Supressores de Tumor , Genômica
8.
Nat Commun ; 13(1): 2690, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577801

RESUMO

The Notch pathway is a conserved cell-cell communication pathway that controls cell fate decisions. Here we sought to determine how Notch pathway activation inhibits the neuroendocrine cell fate in the lungs, an archetypal process for cell fate decisions orchestrated by Notch signaling that has remained poorly understood at the molecular level. Using intratumoral heterogeneity in small-cell lung cancer as a tractable model system, we uncovered a role for the transcriptional regulators REST and YAP as promoters of the neuroendocrine to non-neuroendocrine transition. We further identified the specific neuroendocrine gene programs repressed by REST downstream of Notch in this process. Importantly, we validated the importance of REST and YAP in neuroendocrine to non-neuroendocrine cell fate switches in both developmental and tissue repair processes in the lungs. Altogether, these experiments identify conserved roles for REST and YAP in Notch-driven inhibition of the neuroendocrine cell fate in embryonic lungs, adult lungs, and lung cancer.


Assuntos
Neoplasias Pulmonares , Células Neuroendócrinas , Diferenciação Celular/genética , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Células Neuroendócrinas/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo
9.
Cancer Cell ; 40(11): 1423-1439.e11, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36240778

RESUMO

Intratumoral heterogeneity is a seminal feature of human tumors contributing to tumor progression and response to treatment. Current technologies are still largely unsuitable to accurately track phenotypes and clonal evolution within tumors, especially in response to genetic manipulations. Here, we developed epitopes for imaging using combinatorial tagging (EpicTags), which we coupled to multiplexed ion beam imaging (EpicMIBI) for in situ tracking of barcodes within tissue microenvironments. Using EpicMIBI, we dissected the spatial component of cell lineages and phenotypes in xenograft models of small cell lung cancer. We observed emergent properties from mixed clones leading to the preferential expansion of clonal patches for both neuroendocrine and non-neuroendocrine cancer cell states in these models. In a tumor model harboring a fraction of PTEN-deficient cancer cells, we observed a non-autonomous increase of clonal patch size in PTEN wild-type cancer cells. EpicMIBI facilitates in situ interrogation of cell-intrinsic and cell-extrinsic processes involved in intratumoral heterogeneity.


Assuntos
Neoplasias , Humanos , Epitopos , Neoplasias/patologia , Evolução Clonal , Células Clonais/patologia , Linhagem da Célula , Microambiente Tumoral
10.
Nat Med ; 28(2): 333-344, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35027753

RESUMO

The disialoganglioside GD2 is overexpressed on several solid tumors, and monoclonal antibodies targeting GD2 have substantially improved outcomes for children with high-risk neuroblastoma. However, approximately 40% of patients with neuroblastoma still relapse, and anti-GD2 has not mediated significant clinical activity in any other GD2+ malignancy. Macrophages are important mediators of anti-tumor immunity, but tumors resist macrophage phagocytosis through expression of the checkpoint molecule CD47, a so-called 'Don't eat me' signal. In this study, we establish potent synergy for the combination of anti-GD2 and anti-CD47 in syngeneic and xenograft mouse models of neuroblastoma, where the combination eradicates tumors, as well as osteosarcoma and small-cell lung cancer, where the combination significantly reduces tumor burden and extends survival. This synergy is driven by two GD2-specific factors that reorient the balance of macrophage activity. Ligation of GD2 on tumor cells (a) causes upregulation of surface calreticulin, a pro-phagocytic 'Eat me' signal that primes cells for removal and (b) interrupts the interaction of GD2 with its newly identified ligand, the inhibitory immunoreceptor Siglec-7. This work credentials the combination of anti-GD2 and anti-CD47 for clinical translation and suggests that CD47 blockade will be most efficacious in combination with monoclonal antibodies that alter additional pro- and anti-phagocytic signals within the tumor microenvironment.


Assuntos
Neoplasias Ósseas , Antígeno CD47 , Animais , Linhagem Celular Tumoral , Humanos , Imunoterapia , Camundongos , Recidiva Local de Neoplasia , Fagocitose , Microambiente Tumoral
11.
Cancer Res ; 80(6): 1293-1303, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31969375

RESUMO

Small-cell lung cancer (SCLC) is an aggressive form of lung cancer with dismal survival rates. While kinases often play key roles driving tumorigenesis, there are strikingly few kinases known to promote the development of SCLC. Here, we investigated the contribution of the MAPK module MEK5-ERK5 to SCLC growth. MEK5 and ERK5 were required for optimal survival and expansion of SCLC cell lines in vitro and in vivo. Transcriptomics analyses identified a role for the MEK5-ERK5 axis in the metabolism of SCLC cells, including lipid metabolism. In-depth lipidomics analyses showed that loss of MEK5/ERK5 perturbs several lipid metabolism pathways, including the mevalonate pathway that controls cholesterol synthesis. Notably, depletion of MEK5/ERK5 sensitized SCLC cells to pharmacologic inhibition of the mevalonate pathway by statins. These data identify a new MEK5-ERK5-lipid metabolism axis that promotes the growth of SCLC. SIGNIFICANCE: This study is the first to investigate MEK5 and ERK5 in SCLC, linking the activity of these two kinases to the control of cell survival and lipid metabolism.


Assuntos
Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias Pulmonares/patologia , MAP Quinase Quinase 5/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Animais , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Colesterol/biossíntese , Técnicas de Silenciamento de Genes , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipidômica , Neoplasias Pulmonares/tratamento farmacológico , MAP Quinase Quinase 5/genética , Sistema de Sinalização das MAP Quinases/genética , Ácido Mevalônico/metabolismo , Camundongos , Proteína Quinase 7 Ativada por Mitógeno/genética , RNA-Seq , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cancer Res ; 80(5): 1024-1035, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31900258

RESUMO

Neuroblastoma is a deadly pediatric solid tumor with infrequent recurrent somatic mutations. Particularly, the pathophysiology of tumors without MYCN amplification remains poorly defined. Utilizing an unbiased approach, we performed gene set enrichment analysis of RNA-sequencing data from 498 patients with neuroblastoma and revealed a differentially overexpressed gene signature in MYCN nonamplified neuroblastomas with telomerase reverse transcriptase (TERT) gene overexpression and coordinated activation of oncogenic signaling pathways, including E2Fs, Wnt, Myc, and the DNA repair pathway. Promoter rearrangement of the TERT gene juxtaposes the coding sequence to strong enhancer elements, leading to TERT overexpression and poor prognosis in neuroblastoma, but TERT-associated oncogenic signaling remains unclear. ChIP-seq analysis of the human CLB-GA neuroblastoma cells harboring TERT rearrangement uncovered genome-wide chromatin co-occupancy of Brd4 and H3K27Ac and robust enrichment of H3K36me3 in TERT and multiple TERT-associated genes. Brd4 and cyclin-dependent kinases (CDK) had critical regulatory roles in the expression and chromatin activation of TERT and multiple TERT-associated genes. Epigenetically targeting Brd4 or CDKs with their respective inhibitors suppressed the expression of TERT and multiple TERT-associated genes in neuroblastoma with TERT overexpression or MYCN amplification. ChIP-seq and ChIP-qPCR provided evidence that the CDK inhibitor directly inhibited Brd4 recruitment to activate chromatin globally. Therefore, inhibiting Brd4 and CDK concurrently with AZD5153 and dinaciclib would be most effective in tumor growth suppression, which we demonstrated in neuroblastoma cell lines, primary human cells, and xenografts. In summary, we describe a unique mechanism in neuroblastoma with TERT overexpression and an epigenetically targeted novel therapeutic strategy. SIGNIFICANCE: Epigenetically cotargeting Brd4 and Cdks suppresses human neuroblastoma with TERT overexpression by inhibiting the TERT-associated gene expression networks.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Epigênese Genética/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Telomerase/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Adolescente , Animais , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Pré-Escolar , Cromatina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Óxidos N-Cíclicos , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Compostos Heterocíclicos com 2 Anéis/farmacologia , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Histonas/genética , Humanos , Indolizinas , Camundongos , Neuroblastoma/genética , Neuroblastoma/patologia , Neuroblastoma/cirurgia , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Regiões Promotoras Genéticas , Pirazóis , Piridazinas , Compostos de Piridínio/farmacologia , Compostos de Piridínio/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Cancer Cell ; 38(1): 129-143.e7, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32531271

RESUMO

Using unbiased kinase profiling, we identified protein kinase A (PKA) as an active kinase in small cell lung cancer (SCLC). Inhibition of PKA activity genetically, or pharmacologically by activation of the PP2A phosphatase, suppresses SCLC expansion in culture and in vivo. Conversely, GNAS (G-protein α subunit), a PKA activator that is genetically activated in a small subset of human SCLC, promotes SCLC development. Phosphoproteomic analyses identified many PKA substrates and mechanisms of action. In particular, PKA activity is required for the propagation of SCLC stem cells in transplantation studies. Broad proteomic analysis of recalcitrant cancers has the potential to uncover targetable signaling networks, such as the GNAS/PKA/PP2A axis in SCLC.


Assuntos
Cromograninas/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Neoplasias Pulmonares/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteína Fosfatase 2/metabolismo , Proteômica/métodos , Carcinoma de Pequenas Células do Pulmão/metabolismo , Células A549 , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cromograninas/genética , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Proteína Fosfatase 2/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
Cell Rep ; 16(3): 644-56, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27373157

RESUMO

Small cell lung cancer (SCLC) is a neuroendocrine lung cancer characterized by fast growth, early dissemination, and rapid resistance to chemotherapy. We identified a population of long-term tumor-propagating cells (TPCs) in a mouse model of SCLC. This population, marked by high levels of EpCAM and CD24, is also prevalent in human primary SCLC tumors. Murine SCLC TPCs are numerous and highly proliferative but not intrinsically chemoresistant, indicating that not all clinical features of SCLC are linked to TPCs. SCLC TPCs possess a distinct transcriptional profile compared to non-TPCs, including elevated MYC activity. Genetic and pharmacological inhibition of MYC in SCLC cells to non-TPC levels inhibits long-term propagation but not short-term growth. These studies identify a highly tumorigenic population of SCLC cells in mouse models, cell lines, and patient tumors and a means to target them in this most fatal form of lung cancer.


Assuntos
Neoplasias Pulmonares/patologia , Carcinoma de Pequenas Células do Pulmão/patologia , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/genética , Camundongos , Carcinoma de Pequenas Células do Pulmão/genética , Transcrição Gênica/fisiologia
15.
Genetics ; 190(3): 951-64, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22214610

RESUMO

Mitochondrial DNA (mtDNA) deletions are associated with sporadic and inherited diseases and age-associated neurodegenerative disorders. Approximately 85% of mtDNA deletions identified in humans are flanked by short directly repeated sequences; however, mechanisms by which these deletions arise are unknown. A limitation in deciphering these mechanisms is the essential nature of the mitochondrial genome in most living cells. One exception is budding yeast, which are facultative anaerobes and one of the few organisms for which directed mtDNA manipulation is possible. Using this model system, we have developed a system to simultaneously monitor spontaneous direct-repeat-mediated deletions (DRMDs) in the nuclear and mitochondrial genomes. In addition, the mitochondrial DRMD reporter contains a unique KpnI restriction endonuclease recognition site that is not present in otherwise wild-type (WT) mtDNA. We have expressed KpnI fused to a mitochondrial localization signal to induce a specific mitochondrial double-strand break (mtDSB). Here we report that loss of the MRX (Mre11p, Rad50p, Xrs2p) and Ku70/80 (Ku70p, Ku80p) complexes significantly impacts the rate of spontaneous deletion events in mtDNA, and these proteins contribute to the repair of induced mtDSBs. Furthermore, our data support homologous recombination (HR) as the predominant pathway by which mtDNA deletions arise in yeast, and suggest that the MRX and Ku70/80 complexes are partially redundant in mitochondria.


Assuntos
Reparo do DNA por Junção de Extremidades/fisiologia , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/genética , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Ordem dos Genes , Genoma Mitocondrial , Autoantígeno Ku , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Genéticos , Taxa de Mutação , Fenótipo , Recombinação Genética , Sequências Repetitivas de Ácido Nucleico , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Deleção de Sequência , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA