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1.
Cancer Sci ; 115(2): 672-681, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184804

RESUMEN

The Japan Diabetes Society and the Japan Cancer Association launched a joint committee and published their "First Joint Committee Report on Diabetes and Cancer" in 2013, compiling recommendations for physicians and health-care providers as well as for the general population. In 2016, the "Second Joint Committee Report on Diabetes and Cancer" summarized the current evidence on glycemic control and cancer risk in patients with diabetes. The current "Third Joint Committee Report on Diabetes and Cancer", for which the joint committee also enlisted the assistance of the Japanese Society of Clinical Oncology and the Japanese Society of Medical Oncology, reports on the results from the questionnaire survey, "Diabetes Management in Patients Receiving Cancer Therapy," which targeted oncologists responsible for cancer management and diabetologists in charge of glycemic control in cancer patients. The results of the current survey indicated that there is a general consensus among oncologists and diabetologists with regard to the need for guidelines on glycemic control goals, the relevance of glycemic control, and glycemic control during cancer therapy in cancer patients.


Asunto(s)
Diabetes Mellitus , Neoplasias , Oncólogos , Médicos , Humanos , Japón/epidemiología , Diabetes Mellitus/epidemiología , Neoplasias/epidemiología , Neoplasias/terapia , Encuestas y Cuestionarios
2.
Diabetol Int ; 15(1): 5-18, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38264218

RESUMEN

The Japan Diabetes Society (JDS) and the Japan Cancer Association (JCA) launched a joint committee and published their "First Joint Committee Report on Diabetes and Cancer" in 2013, compiling recommendations for physicians and healthcare providers as well as for the general population. In 2016, the "Second Joint Committee Report on Diabetes and Cancer" summarized the current evidence on glycemic control and cancer risk in patients with diabetes. The current "Third Joint Committee Report on Diabetes and Cancer", for which the joint committee also enlisted the assistance of the Japanese Society of Clinical Oncology (JSCO) and the Japanese Society of Medical Oncology (JSMO), reports on the results from the questionnaire survey, "Diabetes Management in Patients Receiving Cancer Therapy," which targeted oncologists responsible for cancer management and diabetologists in charge of glycemic control in cancer patients. The results of the current survey demonstrated that there is a general consensus among oncologists and diabetologists with regard to the need for guidelines on glycemic control goals, the relevance of glycemic control, and glycemic control during cancer therapy in cancer patients.

3.
J Gastroenterol ; 59(3): 250-262, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38242997

RESUMEN

BACKGROUND: Recent evidence suggests that the presence of microbiome within human pancreatic ductal adenocarcinoma (PDAC) tissue potentially influences cancer progression and prognosis. However, the significance of tumor-resident microbiome remains unclear. We aimed to elucidate the impact of intratumoral bacteria on the pathophysiology and prognosis of human PDAC. METHODS: The presence of intratumoral bacteria was assessed in 162 surgically resected PDACs using quantitative polymerase chain reaction (qPCR) and in situ hybridization (ISH) targeting 16S rRNA. The intratumoral microbiome was explored by 16S metagenome sequencing using DNA extracted from formalin-fixed paraffin-embedded tissues. The profile of intratumoral bacteria was compared with clinical information, pathological findings including tumor-infiltrating T cells, tumor-associated macrophage, fibrosis, and alterations in four main driver genes (KRAS, TP53, CDKN2A/p16, SMAD4) in tumor genomes. RESULTS: The presence of intratumoral bacteria was confirmed in 52 tumors (32%) using both qPCR and ISH. The 16S metagenome sequencing revealed characteristic bacterial profiles within these tumors, including phyla such as Proteobacteria and Firmicutes. Comparison of bacterial profiles between cases with good and poor prognosis revealed a significant positive correlation between a shorter survival time and the presence of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus. The abundance of these bacteria was correlated with a decrease in the number of tumor-infiltrating T cells positive for CD4, CD8, and CD45RO. CONCLUSIONS: Intratumoral infection of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus is correlated with the suppressed anti-PDAC immunity and poor prognosis.


Asunto(s)
Carcinoma Ductal Pancreático , Microbiota , Neoplasias Pancreáticas , Humanos , ARN Ribosómico 16S , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Pronóstico
4.
Br J Cancer ; 129(8): 1251-1260, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37715023

RESUMEN

BACKGROUND: Although genome duplication, or polyploidization, is believed to drive cancer evolution and affect tumor features, its significance in hepatocellular carcinoma (HCC) is unclear. We aimed to determine the characteristics of polyploid HCCs by evaluating chromosome duplication and to discover surrogate markers to discriminate polyploid HCCs. METHODS: The ploidy in human HCC was assessed by fluorescence in situ hybridization for multiple chromosomes. Clinicopathological and expression features were compared between polyploid and near-diploid HCCs. Markers indicating polyploid HCC were explored by transcriptome analysis of cultured HCC cells. RESULTS: Polyploidy was detected in 36% (20/56) of HCCs and discriminated an aggressive subset of HCC that typically showed high serum alpha-fetoprotein, poor differentiation, and poor prognosis compared to near-diploid HCCs. Molecular subtyping revealed that polyploid HCCs highly expressed alpha-fetoprotein but did not necessarily show progenitor features. Histological examination revealed abundant polyploid giant cancer cells (PGCCs) with a distinct appearance and frequent macrotrabecular-massive architecture in polyploid HCCs. Notably, the abundance of PGCCs and overexpression of ubiquitin-conjugating enzymes 2C indicated polyploidy in HCC and efficiently predicted poor prognosis in combination. CONCLUSIONS: Histological diagnosis of polyploidy using surrogate markers discriminates an aggressive subset of HCC, apart from known HCC subgroups, and predict poor prognosis in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , alfa-Fetoproteínas/genética , Hibridación Fluorescente in Situ , Pronóstico , Poliploidía
5.
Respir Investig ; 61(6): 781-792, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37741093

RESUMEN

BACKGROUND: Recent studies suggest that cellular senescence is related to the pathogenesis of idiopathic pulmonary fibrosis. However, cellular senescence has yet to be targeted therapeutically in clinical practice. ARV825, a recently developed BRD4 degrader, has been reported as a novel senolytic drug. Conversely, it has also been reported that BRD4 regulates the pro-fibrotic gene expression of fibroblasts. Therefore, this study focuses on the senolytic and anti-fibrotic effects of ARV825 and evaluated these effects on lung fibrosis. METHODS: Lung fibroblasts were induced to senescence through serial passage. The expression of senescence markers and pro-fibrotic markers were determined through quantitative PCR or immunoblot analysis. Lung fibrosis was induced in mice through intratracheal administration of bleomycin. Mice treated with ARV825 underwent histological analysis of lung fibrosis using the Ashcroft score. Total lung collagen was quantified through a hydroxyproline assay. Respiratory mechanics analysis was performed using the flexiVent system. RESULTS: For senescent cells, ARV825 induced the expression of an apoptosis marker while reducing the expression of BRD4 and senescence markers. On the other hand, for early passage pre-senescent cells, ARV825 reduced the expression of collagen type 1 and α-smooth muscle actin. In an experimental mouse model of lung fibrosis, ARV825 attenuated lung fibrosis and improved lung function. Immunohistochemical staining revealed a significant decrease in the number of senescent alveolar type 2 cells in lung tissue due to ARV825 treatment. CONCLUSIONS: These results suggest that ARV825 may impact the progressive and irreversible course of fibrotic lung diseases.


Asunto(s)
Fibrosis Pulmonar Idiopática , Proteínas Nucleares , Humanos , Ratones , Animales , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/farmacología , Senoterapéuticos , Factores de Transcripción , Pulmón/patología , Fibrosis Pulmonar Idiopática/patología , Bleomicina/metabolismo , Bleomicina/farmacología , Colágeno/metabolismo , Colágeno/farmacología , Ratones Endogámicos C57BL , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/farmacología
6.
FEBS J ; 290(5): 1348-1361, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35106956

RESUMEN

Cellular senescence refers to a state of irreversible cell cycle arrest that can be induced by various cellular stresses and is known to play a pivotal role in tumour suppression. While senescence-associated growth arrest can inhibit the proliferation of cancer-prone cells, the altered secretory profile of senescent cells, termed the senescence-associated secretory phenotype, can contribute to the microenvironment that promotes tumour development. Although the senescence-associated secretory phenotype and its effects on tumorigenesis are both highly context dependent, mechanisms underlying such diversity are becoming better understood, thereby allowing the creation of new strategies to effectively target the senescence-associated secretory phenotype and senescent cells for cancer therapy. In this review, we discuss the current knowledge on cellular senescence and the senescence-associated secretory phenotype to develop a structural understanding of their roles in the tumour microenvironment and provide perspectives for future research, including the possibility of senotherapy for the treatment of cancer.


Asunto(s)
Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Fenotipo , Senescencia Celular/genética , Neoplasias/patología , Carcinogénesis/metabolismo
7.
Commun Biol ; 5(1): 1420, 2022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-36577784

RESUMEN

Cellular senescence caused by oncogenic stimuli is associated with the development of various age-related pathologies through the senescence-associated secretory phenotype (SASP). SASP is mediated by the activation of cytoplasmic nucleic acid sensors. However, the molecular mechanism underlying the accumulation of nucleotide ligands in senescent cells is unclear. In this study, we revealed that the expression of RNaseH2A, which removes ribonucleoside monophosphates (rNMPs) from the genome, is regulated by E2F transcription factors, and it decreases during cellular senescence. Residual rNMPs cause genomic DNA fragmentation and aberrant activation of cytoplasmic nucleic acid sensors, thereby provoking subsequent SASP factor gene expression in senescent cells. In addition, RNaseH2A expression was significantly decreased in aged mouse tissues and cells from individuals with Werner syndrome. Furthermore, RNaseH2A degradation using the auxin-inducible degron system induced the accumulation of nucleotide ligands and induction of certain tumourigenic SASP-like factors, promoting the metastatic properties of colorectal cancer cells. Our results indicate that RNaseH2A downregulation provokes SASP through nucleotide ligand accumulation, which likely contributes to the pathological features of senescent, progeroid, and cancer cells.


Asunto(s)
ADN , Neoplasias , Animales , Ratones , Senescencia Celular/genética , Fragmentación del ADN , Regulación hacia Abajo , Expresión Génica , Genómica , Ligandos , Neoplasias/genética , Neoplasias/metabolismo , Nucleótidos , Fenotipo , Humanos , Línea Celular
8.
Sci Immunol ; 7(72): eabl7209, 2022 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-35749514

RESUMEN

Long-term senescent cells exhibit a secretome termed the senescence-associated secretory phenotype (SASP). Although the mechanisms of SASP factor induction have been intensively studied, the release mechanism and how SASP factors influence tumorigenesis in the biological context remain unclear. In this study, using a mouse model of obesity-induced hepatocellular carcinoma (HCC), we identified the release mechanism of SASP factors, which include interleukin-1ß (IL-1ß)- and IL-1ß-dependent IL-33, from senescent hepatic stellate cells (HSCs) via gasdermin D (GSDMD) amino-terminal-mediated pore. We found that IL-33 was highly induced in senescent HSCs in an IL-1ß-dependent manner in the tumor microenvironment. The release of both IL-33 and IL-1ß was triggered by lipoteichoic acid (LTA), a cell wall component of gut microbiota that was transferred and accumulated in the liver tissue of high-fat diet-fed mice, and the release of these factors was mediated through cell membrane pores formed by the GSDMD amino terminus, which was cleaved by LTA-induced caspase-11. We demonstrated that IL-33 release from HSCs promoted HCC development via the activation of ST2-positive Treg cells in the liver tumor microenvironment. The accumulation of GSDMD amino terminus was also detected in HSCs from human NASH-associated HCC patients, suggesting that similar mechanism could be involved in a certain type of human HCC. These results uncover a release mechanism for SASP factors from sensitized senescent HSCs in the tumor microenvironment, thereby facilitating obesity-associated HCC progression. Furthermore, our findings highlight the therapeutic potential of inhibitors of GSDMD-mediated pore formation for HCC treatment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas de Unión a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Senescencia Celular , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Humanos , Interleucina-33/metabolismo , Ratones , Obesidad/complicaciones , Obesidad/metabolismo , Microambiente Tumoral
9.
Genes Cells ; 27(8): 517-525, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35726163

RESUMEN

The 6th conference of the international cell senescence association (ICSA) on the theme of "A New Era of Senescence Research: The Challenge of Controlling Aging and Cancer" was held on December 12-15, 2021 in Osaka, Japan as a Hybrid Meeting. The conference brought together basic and translational scientists to discuss recent developments in the field of cellular senescence research. In recent years, the study of cellular senescence has become a very hot field of research. It is clear that the ICSA, founded in 2015, has played an important role in this process. The 6th ICSA conference has provided another opportunity for exchanges and new connections between basic and translational scientists. The scientific program consisted of keynote lectures, invited talks, short talks selected from abstracts, a poster session, and luncheon seminars sponsored by the Japanese Society of Anti-Aging Medicine. In the Meet the Editor session, Dr Christoph Schmitt, Editor-in-Chief of Nature Metabolism, gave a short presentation about the journal and answered questions from the audience. Being a hybrid meeting, there was only so much that could be done, but we hope that the meeting was fruitful.


Asunto(s)
Senescencia Celular , Neoplasias , Envejecimiento , Humanos , Japón
10.
Cancer Med ; 11(16): 3194-3206, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35318827

RESUMEN

Accumulating evidence indicates that alterations of gut microbiota are associated with colorectal cancer (CRC). Therefore, the use of gut microbiota for the diagnosis of CRC has received attention. Recently, several studies have been conducted to detect the differences in the gut microbiota between healthy individuals and CRC patients using machine learning-based gut bacterial DNA meta-sequencing analysis, and to use this information for the development of CRC diagnostic model. However, to date, most studies had small sample sizes and/or only cross-validated using the training dataset that was used to create the diagnostic model, rather than validated using an independent test dataset. Since machine learning-based diagnostic models cause overfitting if the sample size is small and/or an independent test dataset is not used for validation, the reliability of these diagnostic models needs to be interpreted with caution. To circumvent these problems, here we have established a new machine learning-based CRC diagnostic model using the gut microbiota as an indicator. Validation using independent test datasets showed that the true positive rate of our CRC diagnostic model increased substantially as CRC progressed from Stage I to more than 60% for CRC patients more advanced than Stage II when the false positive rate was set around 8%. Moreover, there was no statistically significant difference in the true positive rate between samples collected in different cities or in any part of the colorectum. These results reveal the possibility of the practical application of gut microbiota-based CRC screening tests.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/microbiología , Detección Precoz del Cáncer , Humanos , Aprendizaje Automático , Reproducibilidad de los Resultados
11.
Nat Commun ; 12(1): 5674, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34584098

RESUMEN

Emerging evidence is revealing that alterations in gut microbiota are associated with colorectal cancer (CRC). However, very little is currently known about whether and how gut microbiota alterations are causally associated with CRC development. Here we show that 12 faecal bacterial taxa are enriched in CRC patients in two independent cohort studies. Among them, 2 Porphyromonas species are capable of inducing cellular senescence, an oncogenic stress response, through the secretion of the bacterial metabolite, butyrate. Notably, the invasion of these bacteria is observed in the CRC tissues, coinciding with the elevation of butyrate levels and signs of senescence-associated inflammatory phenotypes. Moreover, although the administration of these bacteria into ApcΔ14/+ mice accelerate the onset of colorectal tumours, this is not the case when bacterial butyrate-synthesis genes are disrupted. These results suggest a causal relationship between Porphyromonas species overgrowth and colorectal tumourigenesis which may be due to butyrate-induced senescence.


Asunto(s)
Bacterias/metabolismo , Butiratos/metabolismo , Carcinogénesis/patología , Neoplasias Colorrectales/patología , Microbioma Gastrointestinal , Bacterias/clasificación , Bacterias/genética , Senescencia Celular/fisiología , Neoplasias Colorrectales/microbiología , Células Epiteliales/microbiología , Células Epiteliales/fisiología , Heces/microbiología , Humanos , Intestinos/citología , Intestinos/microbiología , Intestinos/fisiología , Porphyromonas/genética , Porphyromonas/metabolismo , ARN Ribosómico 16S/genética
12.
Cancer Sci ; 112(11): 4433-4443, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34533882

RESUMEN

Gut microbiota and the mammalian host share a symbiotic relationship, in which the host provides a suitable ecosystem for the gut bacteria to digest indigestible nutrients and produce useful metabolites. Although gut microbiota primarily reside in and influence the intestine, they also regulate liver function via absorption and subsequent transfer of microbial components and metabolites through the portal vein to the liver. Due to this transfer, the liver may be continuously exposed to gut-derived metabolites and components. For example, short-chain fatty acids (SCFA) produced by gut microbiota, through the fermentation of dietary fiber, can suppress inflammation via regulatory T cell induction through SCFA-induced epigenetic mechanisms. Additionally, secondary bile acids (BA), such as deoxycholic acid, produced by gut bacteria through the 7α-dehydroxylation of primary BAs, are thought to induce DNA damage and contribute to the remodeling of tumor microenvironments. Other substances that are also thought to influence liver function include lipopolysaccharides (components of the outer membrane of gram-negative bacteria) and lipoteichoic acid (cell wall component of Gram-positive bacteria), which are ligands of innate immune receptors, Toll-like receptor-4, and Toll-like receptor-2, respectively, through which inflammatory signaling is elicited. In this review, we focus on the role of gut microbiota in the liver microenvironment, describing the anatomy of the gut-liver axis, the role of gut microbial metabolites, and the relationships that exist between gut microbiota and liver diseases, including liver cancer.


Asunto(s)
Carcinoma Hepatocelular/etiología , Microbioma Gastrointestinal/fisiología , Neoplasias Hepáticas/etiología , Hígado/fisiología , Microambiente Tumoral/fisiología , Ácidos y Sales Biliares/metabolismo , Senescencia Celular/fisiología , Colina/metabolismo , Daño del ADN , Etanol/metabolismo , Ácidos Grasos Volátiles/metabolismo , Bacterias Grampositivas/metabolismo , Hepatitis Alcohólica/etiología , Humanos , Lipopolisacáridos/metabolismo , Hígado/anatomía & histología , Hígado/metabolismo , Hepatopatías/etiología , Neoplasias Hepáticas/microbiología , Enfermedad del Hígado Graso no Alcohólico/etiología , Simbiosis , Ácidos Teicoicos/metabolismo
13.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34426493

RESUMEN

Cellular senescence causes a dramatic alteration of chromatin organization and changes the gene expression profile of proinflammatory factors, thereby contributing to various age-related pathologies through the senescence-associated secretory phenotype (SASP). Chromatin organization and global gene expression are maintained by the CCCTC-binding factor (CTCF); however, the molecular mechanism underlying CTCF regulation and its association with SASP gene expression remains unclear. We discovered that noncoding RNA (ncRNA) derived from normally silenced pericentromeric repetitive sequences directly impairs the DNA binding of CTCF. This CTCF disturbance increases the accessibility of chromatin and activates the transcription of SASP-like inflammatory genes, promoting malignant transformation. Notably, pericentromeric ncRNA was transferred into surrounding cells via small extracellular vesicles acting as a tumorigenic SASP factor. Because CTCF blocks the expression of pericentromeric ncRNA in young cells, the down-regulation of CTCF during cellular senescence triggers the up-regulation of this ncRNA and SASP-related inflammatory gene expression. In this study, we show that pericentromeric ncRNA provokes chromosomal alteration by inhibiting CTCF, leading to a SASP-like inflammatory response in a cell-autonomous and non-cell-autonomous manner and thus may contribute to the risk of tumorigenesis during aging.


Asunto(s)
Envejecimiento/genética , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Inflamación/genética , ARN no Traducido/fisiología , Fenotipo Secretor Asociado a la Senescencia/genética , Animales , Senescencia Celular/genética , Centrómero , ADN de Neoplasias/metabolismo , Femenino , Regulación de la Expresión Génica , Células HEK293 , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias , Unión Proteica/genética
14.
Cancers (Basel) ; 13(13)2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-34283063

RESUMEN

Oral microbiota is reportedly associated with gut microbiota and influences colorectal cancer (CRC) progression; however, the details remain unclear. This study aimed to evaluate the role of oral microbiota in CRC progression. Fifty-two patients with CRC and 51 healthy controls were included. Saliva and stool samples were collected, and microbiota were evaluated using 16S rRNA analysis and next-generation sequencing. Comparative analysis was performed on both groups. Linear discriminant analysis effect size (LEfSe) revealed the presence of indigenous oral bacteria, such as Peptostreptococcus, Streptococcus, and Solobacterium spp., at a significantly higher relative abundance in saliva and stool samples of CRC patients compared with controls. Next, CRC patients were divided into early stage (Stage I, II; n = 26; 50%) and advanced stage (Stage III, IV; n = 26; 50%) disease. LEfSe revealed that S. moorei was present at a significantly higher relative abundance in the advanced-stage group compared with the early-stage group, again consistent for both saliva and stool samples. Among bacterial species with significantly higher relative abundance in CRC patients, P. stomatis, S. anginosus, S. koreensis, and S. moorei originated from the oral cavity, suggesting indigenous oral bacteria may have promoted initiation of CRC carcinogenesis. Furthermore, S. moorei may influence CRC progression.

15.
Blood Adv ; 4(24): 6175-6188, 2020 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-33351113

RESUMEN

BCR-ABL, an oncogenic fusion gene, plays a central role in the pathogenesis of chronic myeloid leukemia (CML). Oncogenic signaling induces oncogene-induced senescence and senescence-associated secretory phenotype (SASP), which is characterized by enhanced production of various cytokines. BCR-ABL gene transduction confers senescent phenotype in vitro; however, the in vivo relevance of senescence has not been explored in this context. Transplantation of BCR-ABL-expressing hematopoietic stem/progenitor cells caused CML in mice with an increase in bone marrow BCR-ABL+CD41+CD150+ leukemic megakaryocyte-lineage (MgkL) cells, which exhibited enhanced senescence-associated ß-galactosidase staining and increased expression of p16 and p21, key molecules that are crucially involved in senescence. Moreover, knockout of p16 and p21 genes reduced both BCR-ABL-induced abnormal megakaryopoiesis and the maintenance of CML cell leukemogenic capacity, as evidenced by attenuated leukemogenic capacity at secondary transplantation. The expression of transforming growth factor-ß1 (TGF-ß1), a representative SASP molecule, was enhanced in the leukemic MgkL cells, and TGF-ß1 inhibition attenuated CML cell leukemogenic capacity both in vitro and in vivo. Furthermore, BCR-ABL-expressing MgkL cells displayed enhanced autophagic activity, and autophagy inhibition reduced bone marrow MgkL cell number and prolonged the survival of CML mice, which had transiently received the tyrosine kinase inhibitor, imatinib, earlier. Thus, BCR-ABL induced the expansion of senescent leukemic MgkL cells, which supported CML leukemogenesis by providing TGF-ß1.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Megacariocitos , Animales , Proteínas de Fusión bcr-abl/genética , Células Madre Hematopoyéticas , Mesilato de Imatinib/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Ratones
16.
Nat Commun ; 11(1): 1935, 2020 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-32321921

RESUMEN

Although cellular senescence acts primarily as a tumour suppression mechanism, the accumulation of senescent cells in vivo eventually exerts deleterious side effects through inflammatory/tumour-promoting factor secretion. Thus, the development of new drugs that cause the specific elimination of senescent cells, termed senolysis, is anticipated. Here, by an unbiased high-throughput screening of chemical compounds and a bio-functional analysis, we identify BET family protein degrader (BETd) as a promising senolytic drug. BETd provokes senolysis through two independent but integrated pathways; the attenuation of non-homologous end joining (NHEJ), and the up-regulation of autophagic gene expression. BETd treatment eliminates senescent hepatic stellate cells in obese mouse livers, accompanied by the reduction of liver cancer development. Furthermore, the elimination of chemotherapy-induced senescent cells by BETd increases the efficacy of chemotherapy against xenograft tumours in immunocompromised mice. These results reveal the vulnerability of senescent cells and open up possibilities for its control.


Asunto(s)
Antineoplásicos/administración & dosificación , Autofagia/efectos de los fármacos , Senescencia Celular/efectos de los fármacos , Reparación del ADN por Unión de Extremidades/efectos de los fármacos , Neoplasias/fisiopatología , Animales , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
Leukemia ; 33(1): 191-204, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29967380

RESUMEN

In spite of distinct clinical importance, the molecular mechanisms how Additional sex combs-like 1 (ASXL1) mutation contributes to the pathogenesis of premalignant conditions are largely unknown. Here, with newly generated knock-in mice, we investigated the biological effects of the mutant. Asxl1G643fs heterozygous (Asxl1G643fs/+) mice developed phenotypes recapitulating human low-risk myelodysplastic syndromes (MDS), and some of them developed MDS/myeloproliferative neoplasm-like disease after long latency. H2AK119ub1 level around the promoter region of p16Ink4a was significantly decreased in Asxl1G643fs/+ hematopoietic stem cells (HSC), suggesting perturbation of Bmi1-driven H2AK119ub1 histone modification by mutated Asxl1. The mutant form of ASXL1 had no ability to interact with BMI1 as opposed to wild-type ASXL1 protein. Restoration of HSC pool and amelioration of increased apoptosis in hematopoietic stem and progenitor cells were obtained from Asxl1G643fs/+ mice heterozygous for p16Ink4a. These results indicated that loss of protein interaction between Asxl1 mutant and Bmi1 affected the activity of PRC1, and subsequent derepression of p16Ink4a by aberrant histone ubiquitination could induce cellular senescence, resulting in low-risk MDS-like phenotypes in Asxl1G643fs/+ mice. This model provides a useful platform to unveil the molecular basis for hematological disorders induced by ASXL1 mutation and to develop therapeutic strategies for these patients.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/antagonistas & inhibidores , Hematopoyesis , Histonas/química , Mutación , Síndromes Mielodisplásicos/etiología , Complejo Represivo Polycomb 1/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/fisiología , Animales , Apoptosis , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Femenino , Masculino , Ratones Endogámicos C57BL , Síndromes Mielodisplásicos/metabolismo , Síndromes Mielodisplásicos/patología , Complejo Represivo Polycomb 1/genética , Proteínas Proto-Oncogénicas/genética
18.
Sci Rep ; 8(1): 10888, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30022091

RESUMEN

Chromatin dynamics mediated by post-translational modifications play a crucial role in cellular response to genotoxic stress for the maintenance of genome integrity. MDC1 is a pivotal chromatin adaptor in DNA damage response (DDR) and its methylation is essential to recruit repair factors at DNA double-strand break (DSB) sites, yet their precise molecular mechanisms remain elusive. Here we identified euchromatic histone-lysine N-methyltransferase 1 (EHMT1) and EHMT2 as novel regulators of MDC1, which is required for the accumulation of DDR factors e.g. 53BP1 and RAP80, at the DSB sites. MDC1 interacts mainly with EHMT1, which is facilitated by DNA damage-initiated ATM signalling, and EHMT2 dominantly modulates methylation of MDC1 lysine 45. This regulatory modification promotes the interaction between MDC1 and ATM to expand activated ATM on damaged chromatin and dysfunctional telomere. These findings identify EHMT1 and EHMT2 as DDR components, with implications for genome-integrity maintenance through proper dynamic methylation of MDC1.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Daño del ADN , Metilación de ADN , Antígenos de Histocompatibilidad/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Lisina/química , Proteínas Nucleares/química , Transactivadores/química , Proteínas Adaptadoras Transductoras de Señales , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de Ciclo Celular , Cromatina/genética , Cromatina/metabolismo , Reparación del ADN , Inestabilidad Genómica , Antígenos de Histocompatibilidad/genética , N-Metiltransferasa de Histona-Lisina/genética , Histonas , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Células Tumorales Cultivadas
19.
Cell Stem Cell ; 22(5): 713-725.e8, 2018 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-29706577

RESUMEN

Stem cell self-renewal is critical for tissue homeostasis, and its dysregulation can lead to organ failure or tumorigenesis. While obesity can induce varied abnormalities in bone marrow components, it is unclear how diet might affect hematopoietic stem cell (HSC) self-renewal. Here, we show that Spred1, a negative regulator of RAS-MAPK signaling, safeguards HSC homeostasis in animals fed a high-fat diet (HFD). Under steady-state conditions, Spred1 negatively regulates HSC self-renewal and fitness, in part through Rho kinase activity. Spred1 deficiency mitigates HSC failure induced by infection mimetics and prolongs HSC lifespan, but it does not initiate leukemogenesis due to compensatory upregulation of Spred2. In contrast, HFD induces ERK hyperactivation and aberrant self-renewal in Spred1-deficient HSCs, resulting in functional HSC failure, severe anemia, and myeloproliferative neoplasm-like disease. HFD-induced hematopoietic abnormalities are mediated partly through alterations to the gut microbiota. Together, these findings reveal that diet-induced stress disrupts fine-tuning of Spred1-mediated signals to govern HSC homeostasis.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Células Madre Hematopoyéticas/metabolismo , Homeostasis , Estrés Oxidativo , Proteínas Represoras/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Ratones , Ratones Endogámicos , Ratones Noqueados , Proteínas Represoras/deficiencia
20.
Nat Commun ; 9(1): 1249, 2018 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-29593264

RESUMEN

Accumulating evidence indicates that the senescence-associated secretory phenotype (SASP) contributes to many aspects of physiology and disease. Thus, controlling the SASP will have tremendous impacts on our health. However, our understanding of SASP regulation is far from complete. Here, we show that cytoplasmic accumulation of nuclear DNA plays key roles in the onset of SASP. Although both DNase2 and TREX1 rapidly remove the cytoplasmic DNA fragments emanating from the nucleus in pre-senescent cells, the expression of these DNases is downregulated in senescent cells, resulting in the cytoplasmic accumulation of nuclear DNA. This causes the aberrant activation of cGAS-STING cytoplasmic DNA sensors, provoking SASP through induction of interferon-ß. Notably, the blockage of this pathway prevents SASP in senescent hepatic stellate cells, accompanied by a decline of obesity-associated hepatocellular carcinoma development in mice. These findings provide valuable new insights into the roles and mechanisms of SASP and possibilities for their control.


Asunto(s)
Senescencia Celular , Citoplasma/enzimología , Desoxirribonucleasas/metabolismo , Regulación hacia Abajo , Animales , Carcinoma Hepatocelular/enzimología , Línea Celular , Daño del ADN , ADN de Cadena Simple/metabolismo , Exodesoxirribonucleasas/metabolismo , Células Estrelladas Hepáticas/enzimología , Humanos , Interferón beta/metabolismo , Hígado/enzimología , Neoplasias Hepáticas/enzimología , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Fenotipo , Fosfoproteínas/metabolismo , Fosforilación , Interferencia de ARN
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