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1.
Adv Exp Med Biol ; 1287: 31-46, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33034024

RESUMO

The endosomal pathway plays a pivotal role upon signal transduction in the Notch pathway. Recent work on lethal (2) giant discs (lgd) points to an additional critical role in avoiding uncontrolled ligand-independent signalling during trafficking of the Notch receptor through the endosomal pathway to the lysosome for degradation. In this chapter, we will outline the journey of Notch through the endosomal system and present an overview of the current knowledge about Lgd and its mammalian orthologs Lgd1/CC2D1b and Lgd2/CC2D1a. We will then discuss how Notch is activated in the absence of lgd function in Drosophila and ask whether there is evidence that a similar ligand-independent activation of the Notch pathway can also happen in mammals if the orthologs are inactivated.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Neoplasias/metabolismo , Receptores Notch/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Animais , Endossomos/metabolismo , Humanos
2.
Tumour Biol ; 42(10): 1010428320965284, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33028168

RESUMO

Glucose, as the main consuming nutrient of the body, faces different destinies in cancer cells. Glycolysis, oxidative phosphorylation, and pentose phosphate pathways produce different glucose-derived metabolites and thus affect cells' bioenergetics differently. Tumor cells' dependency to aerobic glycolysis and other cancer-specific metabolism changes are known as the cancer hallmarks, distinct cancer cells from normal cells. Therefore, these tumor-specific characteristics receive the limelight as targets for cancer therapy. Glutamine, serine, and fatty acid oxidation together with 5-lipoxygenase are main pathways that have attracted lots of attention for cancer therapy. In this review, we not only discuss different tumor metabolism aspects but also discuss the metabolism roles in the promotion of cancer cells at different stages and their difference with normal cells. Besides, we dissect the inhibitors potential in blocking the main metabolic pathways to introduce the effective and non-effective inhibitors in the field.


Assuntos
Antineoplásicos/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Medicina de Precisão , Antineoplásicos/farmacologia , Ciclo do Ácido Cítrico/efeitos dos fármacos , Metabolismo Energético/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular/métodos , Neoplasias/etiologia , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Medicina de Precisão/métodos
3.
Nat Commun ; 11(1): 4979, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020468

RESUMO

Cellular senescence is a known driver of carcinogenesis and age-related diseases, yet senescence is required for various physiological processes. However, the mechanisms and factors that control the negative effects of senescence while retaining its benefits are still elusive. Here, we show that the rasGAP SH3-binding protein 1 (G3BP1) is required for the activation of the senescent-associated secretory phenotype (SASP). During senescence, G3BP1 achieves this effect by promoting the association of the cyclic GMP-AMP synthase (cGAS) with cytosolic chromatin fragments. In turn, G3BP1, through cGAS, activates the NF-κB and STAT3 pathways, promoting SASP expression and secretion. G3BP1 depletion or pharmacological inhibition impairs the cGAS-pathway preventing the expression of SASP factors without affecting cell commitment to senescence. These SASPless senescent cells impair senescence-mediated growth of cancer cells in vitro and tumor growth in vivo. Our data reveal that G3BP1 is required for SASP expression and that SASP secretion is a primary mediator of senescence-associated tumor growth.


Assuntos
Senescência Celular/fisiologia , DNA Helicases/metabolismo , Neoplasias/patologia , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Células A549 , Animais , Carcinogênese , Linhagem Celular , Movimento Celular , Citocinas/metabolismo , DNA Helicases/antagonistas & inibidores , DNA Helicases/deficiência , Humanos , Inflamação , Camundongos , Neoplasias/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/deficiência , RNA Helicases/antagonistas & inibidores , RNA Helicases/deficiência , Proteínas com Motivo de Reconhecimento de RNA/antagonistas & inibidores , Proteínas com Motivo de Reconhecimento de RNA/deficiência , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/metabolismo
4.
Nat Commun ; 11(1): 4980, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020477

RESUMO

The functions of the proto-oncoprotein c-Myc and the tumor suppressor p53 in controlling cell survival and proliferation are inextricably linked as "Yin and Yang" partners in normal cells to maintain tissue homeostasis: c-Myc induces the expression of ARF tumor suppressor (p14ARF in human and p19ARF in mouse) that binds to and inhibits mouse double minute 2 homolog (MDM2) leading to p53 activation, whereas p53 suppresses c-Myc through a combination of mechanisms involving transcriptional inactivation and microRNA-mediated repression. Nonetheless, the regulatory interactions between c-Myc and p53 are not retained by cancer cells as is evident from the often-imbalanced expression of c-Myc over wildtype p53. Although p53 repression in cancer cells is frequently associated with the loss of ARF, we disclose here an alternate mechanism whereby c-Myc inactivates p53 through the actions of the c-Myc-Inducible Long noncoding RNA Inactivating P53 (MILIP). MILIP functions to promote p53 polyubiquitination and turnover by reducing p53 SUMOylation through suppressing tripartite-motif family-like 2 (TRIML2). MILIP upregulation is observed amongst diverse cancer types and is shown to support cell survival, division and tumourigenicity. Thus our results uncover an inhibitory axis targeting p53 through a pan-cancer expressed RNA accomplice that links c-Myc to suppression of p53.


Assuntos
Neoplasias/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Carcinogênese , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/genética , RNA Longo não Codificante/genética , Sumoilação , Proteína Supressora de Tumor p53/genética , Ubiquitinação
5.
Medicine (Baltimore) ; 99(41): e22678, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031336

RESUMO

BACKGROUND: As a member of the N-myc down-regulated gene family, N-Myc downstream-regulated gene 2 (NDRG2) contributes to the tumorigenesis of various types of cancers. However, the correlation between NDRG2 expression and the prognosis of solid tumor remains to be elucidated because of small sample sizes and inconsistent results in previous studies. In the present study, we conducted a systematic review and meta-analysis to explore the prognostic significance of NDRG2 in human solid tumors. METHODS: PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure, and WanFang databases (up to April 2020) were searched for relevant studies that evaluated the impact of NDRG2 on clinical outcomes, including overall survival (OS), and disease-free survival (DFS), in solid tumors. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled to assess the association between NDRG2 expression and the survival of patients with solid tumors. Odds ratios (ORs) with 95% CIs were pooled to estimate the correlation between NDRG2 expression and clinicopathologic characteristics in the patients. RESULTS: A total of 13 eligible studies with 1980 patients were included in this meta-analysis. Low NDRG2 expression was significantly associated with poor OS (HR = 1.96, 95% CI: 1.60-2.40, P < .001) and DFS (HR = 2.70, 95% CI: 1.42-5.13, P = .002) in solid tumor. Furthermore, low NDRG2 expression was related to some phenotypes of tumor aggressiveness, such as clinical stage (OR = 3.21, 95% CI: 1.96-5.26, P < .001), lymph node metastasis (OR = 2.14, 95% CI: 1.49-3.07, P < .001), and degree of differentiation (OR = 0.60, 95% CI: 0.45-0.81, P = .001). CONCLUSIONS: NDRG2 may be a meaningful biomarker of poor prognosis and a potential therapeutic target for human solid tumors.


Assuntos
Neoplasias/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Estudos de Coortes , Humanos , Neoplasias/diagnóstico , Prognóstico
6.
Yakugaku Zasshi ; 140(10): 1243-1249, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32999203

RESUMO

Here the author describes the tumor-selective delivery of a fluorescence photosensitizing agent and an antitumor agent, based on the polymer effect of an N-(2-hydroxypropyl)methacrylamide (HPMA) based copolymer, by utilizing the enhanced permeability and retention (EPR) effect seen in solid tumors. Firstly, the tumor distribution of the photosensitizer, zinc-protoporphyrin IX (ZnPP), was significantly increased by conjugation with the HPMA polymer (P-ZnPP). The P-ZnPP suppressed tumor growth by local generation of cytotoxic singlet oxygen, and the tumor tissue was visualized by fluorescence upon light irradiation. Subsequently, a two-step mechanism for tumor selectivity was observed for the cytotoxic anthracycline, pirarubicin (THP), which conjugated the HPMA-based copolymer via a hydrazone bond (P-THP). The EPR-dependent accumulation of P-THP and the tumor-selective release of THP in the tumor tissues led to highly tumor-selective toxicity. Rapid cell uptake of THP compared to other anthracyclines, and deeper P-THP penetration of the tumor cell spheroid were attributed to the superior antitumor activity of P-THP. The molecular weight of P-THP affected its antitumor activity; oligomeric P-THP derivatives with higher molecular weights, DP-THP and SP-THP, showed even higher antitumor activity. P-THP was effective for both implanted tumor and autochthonous tumor models. These results indicate that nano-sized anticancer drugs based on polymer effect are promising clinical therapeutics.


Assuntos
Antineoplásicos , Sistemas de Liberação de Medicamentos , Desenvolvimento de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fármacos Fotossensibilizantes , Polímeros , Protoporfirinas , Animais , Antraciclinas/química , Antraciclinas/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Doxorrubicina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Terapia de Alvo Molecular , Peso Molecular , Neoplasias/patologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Protoporfirinas/química , Protoporfirinas/metabolismo
7.
Nat Commun ; 11(1): 4907, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999289

RESUMO

Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.


Assuntos
Materiais Biomiméticos/administração & dosagem , Matriz Extracelular/química , Neoplasias/terapia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/efeitos da radiação , Materiais Biomiméticos/química , Materiais Biomiméticos/efeitos da radiação , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Quimiorradioterapia/métodos , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos da radiação , Feminino , Fibrinogênio/administração & dosagem , Fibrinogênio/química , Fibrinogênio/efeitos da radiação , Géis , Humanos , Injeções Intravenosas , Metabolômica , Camundongos , Neoplasias/metabolismo , Trombina/administração & dosagem , Trombina/química , Trombina/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas
8.
PLoS Comput Biol ; 16(9): e1008202, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925922

RESUMO

Hydrogen peroxide (H2O2) promotes a range of phenotypes depending on its intracellular concentration and dosing kinetics, including cell death. While this qualitative relationship has been well established, the quantitative and mechanistic aspects of H2O2 signaling are still being elucidated. Mitochondria, a putative source of intracellular H2O2, have recently been demonstrated to be particularly vulnerable to localized H2O2 perturbations, eliciting a dramatic cell death response in comparison to similar cytosolic perturbations. We sought to improve our dynamic and mechanistic understanding of the mitochondrial H2O2 reaction network in HeLa cells by creating a kinetic model of this system and using it to explore basal and perturbed conditions. The model uses the most current quantitative proteomic and kinetic data available to predict reaction rates and steady-state concentrations of H2O2 and its reaction partners within individual mitochondria. Time scales ranging from milliseconds to one hour were simulated. We predict that basal, steady-state mitochondrial H2O2 will be in the low nM range (2-4 nM) and will be inversely dependent on the total pool of peroxiredoxin-3 (Prx3). Neglecting efflux of H2O2 to the cytosol, the mitochondrial reaction network is expected to control perturbations well up to H2O2 generation rates ~50 µM/s (0.25 nmol/mg-protein/s), above which point the Prx3 system would be expected to collapse. Comparison of these results with redox Western blots of Prx3 and Prx2 oxidation states demonstrated reasonable trend agreement at short times (≤ 15 min) for a range of experimentally perturbed H2O2 generation rates. At longer times, substantial efflux of H2O2 from the mitochondria to the cytosol was evidenced by peroxiredoxin-2 (Prx2) oxidation, and Prx3 collapse was not observed. A refined model using Monte Carlo parameter sampling was used to explore rates of H2O2 efflux that could reconcile model predictions of Prx3 oxidation states with the experimental observations.


Assuntos
Peróxido de Hidrogênio/metabolismo , Mitocôndrias/metabolismo , Modelos Biológicos , Neoplasias/metabolismo , Biologia Computacional , Citosol/química , Citosol/metabolismo , Células HeLa , Humanos , Cinética , Mitocôndrias/química , Neoplasias/química , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia
9.
PLoS Comput Biol ; 16(9): e1008182, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32931516

RESUMO

Recent advances in experimental biology allow creation of datasets where several genome-wide data types (called omics) are measured per sample. Integrative analysis of multi-omic datasets in general, and clustering of samples in such datasets specifically, can improve our understanding of biological processes and discover different disease subtypes. In this work we present MONET (Multi Omic clustering by Non-Exhaustive Types), which presents a unique approach to multi-omic clustering. MONET discovers modules of similar samples, such that each module is allowed to have a clustering structure for only a subset of the omics. This approach differs from most existent multi-omic clustering algorithms, which assume a common structure across all omics, and from several recent algorithms that model distinct cluster structures. We tested MONET extensively on simulated data, on an image dataset, and on ten multi-omic cancer datasets from TCGA. Our analysis shows that MONET compares favorably with other multi-omic clustering methods. We demonstrate MONET's biological and clinical relevance by analyzing its results for Ovarian Serous Cystadenocarcinoma. We also show that MONET is robust to missing data, can cluster genes in multi-omic dataset, and reveal modules of cell types in single-cell multi-omic data. Our work shows that MONET is a valuable tool that can provide complementary results to those provided by existent algorithms for multi-omic analysis.


Assuntos
Algoritmos , Genômica/métodos , Análise por Conglomerados , Bases de Dados Genéticas , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Análise de Célula Única
10.
Nat Commun ; 11(1): 4840, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973129

RESUMO

Immunotherapies revolutionized cancer treatment by harnessing the immune system to target cancer cells. However, most patients are resistant to immunotherapies and the mechanisms underlying this resistant is still poorly understood. Here, we report that overexpression of BMP7, a member of the TGFB superfamily, represents a mechanism for resistance to anti-PD1 therapy in preclinical models and in patients with disease progression while on immunotherapies. BMP7 secreted by tumor cells acts on macrophages and CD4+ T cells in the tumor microenvironment, inhibiting MAPK14 expression and impairing pro-inflammatory responses. Knockdown of BMP7 or its neutralization via follistatin in combination with anti-PD1 re-sensitizes resistant tumors to immunotherapies. Thus, we identify the BMP7 signaling pathway as a potential immunotherapeutic target in cancer.


Assuntos
Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imunoterapia/métodos , Neoplasias/metabolismo , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Linfócitos T CD4-Positivos , Linhagem Celular Tumoral , Feminino , Folistatina/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Proteína Quinase 14 Ativada por Mitógeno/genética , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Receptor de Morte Celular Programada 1/efeitos dos fármacos , Células RAW 264.7 , Proteína Smad1/metabolismo , Transcriptoma , Microambiente Tumoral/efeitos dos fármacos
11.
Life Sci ; 259: 118387, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32890603

RESUMO

Telomerase is a nucleoprotein reverse transcriptase that maintains the telomere, a protective structure at the ends of the chromosome, and is active in cancer cells, stem cells, and fetal cells. Telomerase immortalizes cancer cells and induces unlimited cell division by preventing telomere shortening. Immortalized cancer cells have unlimited proliferative potential due to telomerase activity that causes tumorigenesis and malignancy. Therefore, telomerase can be a lucrative anti-cancer target. The regulation of catalytic subunit of telomerase (TERT) determines the extent of telomerase activity. miRNAs, as an endogenous regulator of gene expression, can control telomerase activity by targeting TERT mRNA. miRNAs that have a decreasing effect on TERT translation mediate modulation of telomerase activity in cancer cells by binding to TERT mRNA and regulating TERT translation. In this review, we provide an update on miRNAs that influence telomerase activity by regulation of TERT translation.


Assuntos
MicroRNAs/metabolismo , Neoplasias/enzimologia , Telomerase/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo
12.
Anticancer Res ; 40(10): 5877-5881, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988918

RESUMO

BACKGROUND/AIM: Pleural effusion (PE) has a heterogeneous aetiology, and differential diagnosis between benign and malignant disease may require invasive procedures in up to 60% of cases. The sensitivity of pleural cytology is limited, and several strategies have been tested to reduce the need of invasive diagnostic approaches. The aim of this study was to evaluate the usefulness of pleural fluid cytology, compared to, and combined with, carcinoembryonic antigen (CEA), C reactive protein (CRP), and lactate dehydrogenase (LDH) assay of pleural fluid (PF) in patients with a history of cancer, exudative non-purulent PE, and suspicion of malignant PE on imaging studies. PATIENTS AND METHODS: The medical records of 40 patients with pulmonary metastases and malignant PE, and 57 controls with benign exudative PE were reviewed. All the patients underwent pleural cytology and CEA, CRP, and LDH assay before VATS-guided biopsy. RESULTS: The sensitivity and specificity were 55.0% and 98.2% (cytology), 35.0% and 98.2% (CEA), 92.5% and 71.9% (CRP), 70.0% and 54.4% (LDH). The multivariate analysis excluded LDH, and the final AUC (cytology+CEA+CRP) was 0.894. CONCLUSION: In all patients with a history of cancer and PE of uncertain origin, the combination of PF cytology plus pleural CEA and CRP assay together should be suggested to recognize malignant plural effusion (MPE), minimising the use of unnecessary invasive investigations.


Assuntos
Diagnóstico Diferencial , Neoplasias/diagnóstico , Pleura/metabolismo , Derrame Pleural Maligno/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Proteína C-Reativa/metabolismo , Antígeno Carcinoembrionário/metabolismo , Citodiagnóstico/métodos , Feminino , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Neoplasias/patologia , Pleura/patologia , Derrame Pleural Maligno/metabolismo , Derrame Pleural Maligno/patologia
13.
Adv Exp Med Biol ; 1268: 307-318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32918225

RESUMO

It has now been convincingly shown that vitamin D and p53 signaling protect against spontaneous or carcinogen-induced malignant transformation of cells. The vitamin D receptor (VDR) and the p53/p63/p73 proteins (the p53 family hereafter) exert their effects as receptors/sensors that turn into transcriptional regulators upon stimulus. While the p53 clan, mostly in the nucleoplasm, responds to a large and still growing number of alterations in cellular homeostasis commonly referred to as stress, the nuclear VDR is transcriptionally activated after binding its naturally occurring biologically active ligand 1,25-dihydroxyvitamin D with high affinity. Interestingly, a crosstalk between vitamin D and p53 signaling has been demonstrated that occurs at different levels, has genome-wide implications, and is of high importance for many malignancies, including non-melanoma skin cancer. These interactions include the ability of p53 to upregulate skin pigmentation via POMC derivatives including alpha-MSH and ACTH. Increased pigmentation protects the skin against UV-induced DNA damage and skin photocarcinogenesis, but also inhibits cutaneous synthesis of vitamin D. A second level of interaction is characterized by binding of VDR and p53 protein, an observation that may be of relevance for the ability of 1,25-dihydroxyvitamin D to increase the survival of skin cells after UV irradiation. UV irradiation-surviving cells show significant reductions in thymine dimers in the presence of 1,25-dihydroxyvitamin D that are associated with increased nuclear p53 protein expression and significantly reduced NO products. A third level of interaction is documented by the ability of vitamin D compounds to regulate the expression of the murine double minute (MDM2) gene in dependence of the presence of wild-type p53. MDM2 has a well-established role as a key negative regulator of p53 activity. Finally, p53 and its family members have been implicated in the direct regulation of the VDR. This review gives an update on some of the implications of the crosstalk between vitamin D and p53 signaling for carcinogenesis in the skin and other tissues, focusing on a genome-wide perspective.


Assuntos
Neoplasias/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Vitamina D/metabolismo , Animais , Humanos , Raios Ultravioleta/efeitos adversos , Vitaminas/metabolismo
14.
Nature ; 585(7824): 277-282, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879489

RESUMO

Abnormal epigenetic patterns correlate with effector T cell malfunction in tumours1-4, but the cause of this link is unknown. Here we show that tumour cells disrupt methionine metabolism in CD8+ T cells, thereby lowering intracellular levels of methionine and the methyl donor S-adenosylmethionine (SAM) and resulting in loss of dimethylation at lysine 79 of histone H3 (H3K79me2). Loss of H3K79me2 led to low expression of STAT5 and impaired T cell immunity. Mechanistically, tumour cells avidly consumed methionine and outcompeted T cells for methionine by expressing high levels of the methionine transporter SLC43A2. Genetic and biochemical inhibition of tumour SLC43A2 restored H3K79me2 in T cells, thereby boosting spontaneous and checkpoint-induced tumour immunity. Moreover, methionine supplementation improved the expression of H3K79me2 and STAT5 in T cells, and this was accompanied by increased T cell immunity in tumour-bearing mice and patients with colon cancer. Clinically, tumour SLC43A2 correlated negatively with T cell histone methylation and functional gene signatures. Our results identify a mechanistic connection between methionine metabolism, histone patterns, and T cell immunity in the tumour microenvironment. Thus, cancer methionine consumption is an immune evasion mechanism, and targeting cancer methionine signalling may provide an immunotherapeutic approach.


Assuntos
Sistema L de Transporte de Aminoácidos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Histonas/metabolismo , Metionina/metabolismo , Metilação , Neoplasias/metabolismo , Sistema L de Transporte de Aminoácidos/deficiência , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Histonas/química , Humanos , Camundongos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Transcrição STAT5/metabolismo
16.
Nat Commun ; 11(1): 4455, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901005

RESUMO

Dysregulated alternative splicing (AS) driving carcinogenetic mitosis remains poorly understood. Here, we demonstrate that cancer metastasis-associated antigen 1 (MTA1), a well-known oncogenic chromatin modifier, broadly interacts and co-expresses with RBPs across cancers, contributing to cancerous mitosis-related AS. Using developed fCLIP-seq technology, we show that MTA1 binds abundant transcripts, preferentially at splicing-responsible motifs, influencing the abundance and AS pattern of target transcripts. MTA1 regulates the mRNA level and guides the AS of a series of mitosis regulators. MTA1 deletion abrogated the dynamic AS switches of variants for ATRX and MYBL2 at mitotic stage, which are relevant to mitosis-related tumorigenesis. MTA1 dysfunction causes defective mitotic arrest, leads to aberrant chromosome segregation, and results in chromosomal instability (CIN), eventually contributing to tumorigenesis. Currently, little is known about the RNA splicing during mitosis; here, we uncover that MTA1 binds transcripts and orchestrates dynamic splicing of mitosis regulators in tumorigenesis.


Assuntos
Carcinogênese/genética , Carcinogênese/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Mitose/fisiologia , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Processamento Alternativo , Animais , Sítios de Ligação/genética , Montagem e Desmontagem da Cromatina/genética , Instabilidade Cromossômica , Feminino , Células HCT116 , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Mitose/genética , Neoplasias/genética , Neoplasias/metabolismo , Precursores de RNA/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transativadores/antagonistas & inibidores , Transativadores/genética
17.
Life Sci ; 259: 118171, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738362

RESUMO

Hypoxia, an important feature of the tumor microenvironment, is responsible for the chemo-resistance and metastasis of malignant solid tumors. Recent studies indicated that mitochondria undergo morphological transitions as an adaptive response to maintain self-stability and connectivity under hypoxic conditions. NAD+ may not only provide reducing equivalents for biosynthetic reactions and in determining energy production, but also functions as a signaling molecule in mitochondrial dynamics regulation. In this review, we describe the upregulated KDAC deacetylase expression in the mitochondria and cytoplasm of tumor cells that results from sensing the changes in NAD+ to control mitochondrial dynamics and distribution, which is responsible for survival and metastasis in hypoxia.


Assuntos
Hipóxia/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , NAD/metabolismo , Metástase Neoplásica , Neoplasias/metabolismo , Animais , Resistencia a Medicamentos Antineoplásicos , Humanos , Microambiente Tumoral
18.
Life Sci ; 259: 118184, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32763290

RESUMO

Autophagy is an essential mechanism of cellular degradation, a way to protect the cells under stress conditions, such as deprivation of nutrients, growth factors and cellular damage. However, in normal physiology autophagy plays a significant role in cancer cells. Current research is in progress to understand how autophagy and cancer cells go hand in hand to support cancer cell progression. The important aspect in cancer and autophagy is the interdependence of autophagy in the survival and progression of cancer cells. Autophagy is known to be a major cause of chemotherapeutic resistance in various cancer cell types. Therefore, inhibition of autophagy as an effective therapeutic approach is being actively studied and tested in clinical studies. Multiple metabolic pathways are linked with autophagy that could potentially be a significant target for chemotherapeutic strategy. The comprehension of the interconnection of autophagy with cancer metabolism can pave a novel findings for effective combinatorial therapeutic strategies.


Assuntos
Autofagia , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias/tratamento farmacológico
19.
Medicine (Baltimore) ; 99(30): e20428, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32791660

RESUMO

BACKGROUND: The prognostic significance of CD44 variant-9 (CD44v9) expression in human cancers has been investigated in several studies, however, definite conclusion has not be reached. The aim of this systematic review and meta-analysis was to evaluate the prognostic significance of CD44v9 expression in various cancers. METHODS: Three common databases were searched and retrieved studies were assessed using the inclusion and exclusion criteria. The further analyses for overall survival (OS), recurrence-free survival (RFS), and clinicopathological parameters were performed. RESULTS: Fifteen studies containing 1633 cancer patients were included into this research. Patients with positive CD44v9 expression tended to have shorter OS (hazard ratio [HR] = 1.93, 95% confidence interval [CI] = 1.48-2.52, P < .01) and RFS (HR = 3.60, 95% CI = 1.52-8.53, P < .01) when compared with patients with negative CD44v9 expression. Positive CD44v9 expression was associated with larger tumor size (P = .04), deeper tumor invasion (P < .01), earlier lymph node metastasis (P < .01), and more advanced clinical stage (P < .01) when compared with negative CD44v9 expression. CONCLUSION: Positive CD44v9 expression predicted worse prognosis in human cancers compared with negative CD44v9 expression. CD44v9 expression could serve as a prognostic factor of human cancers.


Assuntos
Receptores de Hialuronatos/metabolismo , Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Humanos , Neoplasias/diagnóstico , Neoplasias/mortalidade , Prognóstico
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