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1.
Commun Biol ; 7(1): 510, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684876

RESUMEN

Deregulation of the Wnt/ß-catenin pathway is associated with the development of human cancer including colorectal and liver cancer. Although we previously showed that histidine ammonia lyase (HAL) was transcriptionally reduced by the ß-catenin/TCF complex in liver cancer cells, the mechanism(s) of its down-regulation by the complex remain to be clarified. In this study, we search for the transcription factor(s) regulating HAL, and identify CEBPA and FOXA1, two factors whose expression is suppressed by the knockdown of ß-catenin or TCF7L2. In addition, RNA-seq analysis coupled with genome-wide mapping of CEBPA- and FOXA1-binding regions reveals that these two factors also increase the expression of arginase 1 (ARG1) that catalyzes the hydrolysis of arginine. Metabolome analysis discloses that activated Wnt signaling augments intracellular concentrations of histidine and arginine, and that the signal also increases the level of lactic acid suggesting the induction of the Warburg effect in liver cancer cells. Further analysis reveals that the levels of metabolites of the urea cycle and genes coding its related enzymes are also modulated by the Wnt signaling. These findings shed light on the altered cellular metabolism in the liver by the Wnt/ß-catenin pathway through the suppression of liver-enriched transcription factors including CEBPA and FOXA1.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito , Neoplasias Hepáticas , Vía de Señalización Wnt , beta Catenina , Humanos , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Factor Nuclear 3-alfa del Hepatocito/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , beta Catenina/metabolismo , beta Catenina/genética , Aminoácidos/metabolismo , Línea Celular Tumoral , Proteína 2 Similar al Factor de Transcripción 7/metabolismo , Proteína 2 Similar al Factor de Transcripción 7/genética
2.
Oncology ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38262376

RESUMEN

INTRODUCTION: Pseudomyxoma peritonei (PMP) is a disease characterized by progressive accumulation of intraperitoneal mucinous ascites produced by neoplasms in the abdominal cavity. Since the prognosis of patients with PMP remain unsatisfactory, the development of effective therapeutic drug(s) is a matter of pressing concern. Genetic analyses of PMP have clarified the frequent activation of GNAS and/or KRAS. However, the involvement of global epigenetic alterations in PMPs has not been reported. METHODS: To clarify the genetic background of the 15 PMP tumors, we performed genetic analysis using AmpliSeq Cancer HotSpot Panel v2. We further investigated global DNA methylation in the 15 tumors and eight non-cancerous colonic epithelial cells using Methylation EPIC array BeadChip (Infinium 850k) containing a total of 865,918 probes. RESULTS: This is the first report of comprehensive DNA methylation profiles of PMPs in the world. We clarified that the 15 PMPs could be classified into at least two epigenotypes, unique methylation epigenotype (UME) and normal-like methylation epigenotype (NLME), and that genes associated with neuronal development and synaptic signaling may be involved in the development of PMPs. In addition, we identified a set of hypermethylation marker genes such as HOXD1 and TSPYL5 in the 15 PMPs. CONCLUSIONS: These findings may help the understanding of the molecular mechanism(s) of PMP and contribute to the development of therapeutic strategies for this life-threatening disease.

3.
Oncol Rep ; 51(1)2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38063270

RESUMEN

PVRL4 (or nectin­4) is a promising therapeutic target since its upregulated expression is found in a wide range of human cancer types. Enfortumab vedotin, an antibody­drug conjugate targeting PVRL4, is clinically used for the treatment of urothelial bladder cancer. In addition, rMV­SLAMblind, a genetically engineered oncolytic measles virus, can infect cancer cells and induce apoptosis through interaction with PVRL4. Although PVRL4 transcript levels are elevated in breast, lung and ovarian cancer, the mechanisms of its upregulation have not yet been uncovered. To clarify the regulatory mechanisms of elevated PVRL4 expression in breast cancer cells, Assay for Transposase­Accessible Chromatin­sequencing and chromatin immunoprecipitation­sequencing (ChIP­seq) data were used to search for its regulatory regions. Using breast cancer cells, an enhancer region was ultimately identified. Additional analyses, including ChIP and reporter assays, demonstrated that FOS interacted with the PVRL4 enhancer region, and that alterations of the FOS­binding motifs in the enhancer region decreased reporter activity. Consistent with these data, exogenous expression of FOS enhanced the reporter activity and PVRL4 expression in breast cancer cells. Furthermore, RNA­seq analysis using breast cancer cells treated with PVRL4 small interfering RNA revealed its possible involvement in the cytokine response and immune system. These data suggested that FOS was involved, at least partly, in the regulation of PVRL4 expression in breast cancer cells, and that elevated PVRL4 expression may regulate the response of cancer cells to cytokines and the immune system.


Asunto(s)
Neoplasias de la Mama , Nectinas , Virus Oncolíticos , Femenino , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Virus del Sarampión/genética , Virus del Sarampión/metabolismo , Virus Oncolíticos/genética , ARN Interferente Pequeño , Nectinas/genética , Nectinas/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo
4.
iScience ; 26(4): 106563, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37123243

RESUMEN

Bromodomain-containing protein 8 (BRD8) is a subunit of the NuA4/TIP60-histone acetyltransferase complex. Although BRD8 has been considered to act as a co-activator of the complex, its biological role remains to be elucidated. Here, we uncovered that BRD8 accumulates in colorectal cancer cells through the inhibition of ubiquitin-dependent protein degradation by the interaction with MRG domain binding protein. Transcriptome analysis coupled with genome-wide mapping of BRD8-binding sites disclosed that BRD8 transactivates a set of genes independently of TIP60, and that BRD8 regulates the expression of multiple subunits of the pre-replicative complex in concert with the activator protein-1. Depletion of BRD8 induced cell-cycle arrest at the G1 phase and suppressed cell proliferation. We have also shown that the bromodomain of BRD8 is indispensable for not only the interaction with histone H4 or transcriptional regulation but also its own protein stability. These findings highlight the importance of bromodomain as a therapeutic target.

5.
Cancer Med ; 12(12): 13426-13437, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37096864

RESUMEN

BACKGROUND: Abnormal activation of Wnt/ß-catenin signaling is associated with various aspects of cancer development. This study explored the roles of novel target genes of the Wnt/ß-catenin signaling pathway in cancer cells. METHODS: Using the haploid chronic myelogenous leukemia cell line HAP1, RNA sequencing (RNA-seq) was performed to identify genes whose expression was increased by APC disruption and reversed by ß-catenin knockdown (KD). The regulatory mechanism and function of one of the candidate genes was investigated in colorectal cancer (CRC) cells. RESULTS: In total, 64 candidate genes whose expression was regulated by Wnt/ß-catenin signaling were identified. Of these candidate genes, the expression levels of six were reduced by ß-catenin KD in HCT116 CRC cells in our previous microarray. One of these genes was Visinin-like 1 (VSNL1), which belongs to the neuronal calcium-sensor gene family. The expression of VSNL1 was regulated by the ß-catenin/TCF7L2 complex via two TCF7L2-binding elements in intron 1. VSNL1 KD-induced apoptosis in VSNL1-positive CRC cells. Additionally, forced expression of wild-type VSNL1, but not a myristoylation, Ca2+ -binding, or dimerization-defective mutant, suppressed the apoptosis induced by camptothecin and doxorubicin in VSNL1-negative CRC cells. CONCLUSION: Our findings suggest that VSNL1, a novel target gene of the Wnt/ß-catenin signaling pathway, is associated with apoptosis resistance in CRC cells.


Asunto(s)
Neoplasias Colorrectales , Neurocalcina , Vía de Señalización Wnt , Humanos , Apoptosis/genética , beta Catenina/genética , beta Catenina/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica , Vía de Señalización Wnt/genética , Neurocalcina/genética
6.
Cancer Sci ; 114(3): 948-960, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36382598

RESUMEN

The Wnt/ß-catenin signaling pathway plays a key role in development and carcinogenesis. Although some target genes of this signaling have been identified in various tissues and neoplasms, the comprehensive understanding of the target genes and their roles in the development of human cancer, including hepatoma and colorectal cancer remain to be fully elucidated. In this study, we searched for genes regulated by the Wnt signaling in liver cancer using HuH-7 hepatoma cells. A comparison of the expression profiles between cells expressing an active form of mutant ß-catenin and cells expressing enhanced green fluorescent protein (EGFP) identified seven genes upregulated by the mutant ß-catenin gene (CTNNB1). Among the seven genes, we focused in this study on ODAM, odontogenic, ameloblast associated, as a novel target gene. Interestingly, its expression was frequently upregulated in hepatocellular carcinoma, colorectal adenocarcinoma, and hepatoblastoma. We additionally identified a distant enhancer region that was associated with the ß-catenin/TCF7L2 complex. Further analyses revealed that ODAM plays an important role in the regulation of the cell cycle, DNA synthesis, and cell proliferation. These data may be useful for clarification of the main molecular mechanism(s) underlying these cancers.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Vía de Señalización Wnt/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , beta Catenina/genética , Ameloblastos/metabolismo , Ameloblastos/patología , Neoplasias Hepáticas/patología , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica
7.
Oncol Lett ; 24(2): 282, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35814826

RESUMEN

Aberrant activation of the Wnt/ß-catenin signaling pathway plays a crucial role in the development and progression of colorectal cancer. Previously, we identified a set of candidate genes that were regulated by this signaling pathway, and the present study focused on motile sperm domain containing 1 (MOSPD1). Immunohistochemical staining revealed that the expression of MOSPD1 was elevated in tumor cells from colorectal cancer tissues compared with in non-tumor cells. Using ChIP-seq data and the JASPAR database, the regulatory region(s) in the MOSPD1 gene as a target of the Wnt/ß-catenin signaling pathway were searched, and a region containing three putative TCF-binding motifs in the 3'-flanking region was identified. Additional analyses using reporter assay and ChIP-quantitative PCR suggested that this region harbors enhancer activity through an interaction with transcription factor 7 like 2 (TCF7L2) and ß-catenin. In addition, chromatin conformation capture assay revealed that the 3'-flanking region interacts with the MOSPD1 promoter. These data suggested that MOSPD1 was regulated by the ß-catenin/TCF7L2 complex through the enhancer element located in the 3'-flanking region. These findings may be helpful for future studies regarding the precise regulatory mechanisms of MOSPD1.

8.
J Clin Invest ; 132(11)2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35380992

RESUMEN

Enhanced de novo lipogenesis mediated by sterol regulatory element-binding proteins (SREBPs) is thought to be involved in nonalcoholic steatohepatitis (NASH) pathogenesis. In this study, we assessed the impact of SREBP inhibition on NASH and liver cancer development in murine models. Unexpectedly, SREBP inhibition via deletion of the SREBP cleavage-activating protein (SCAP) in the liver exacerbated liver injury, fibrosis, and carcinogenesis despite markedly reduced hepatic steatosis. These phenotypes were ameliorated by restoring SREBP function. Transcriptome and lipidome analyses revealed that SCAP/SREBP pathway inhibition altered the fatty acid (FA) composition of phosphatidylcholines due to both impaired FA synthesis and disorganized FA incorporation into phosphatidylcholine via lysophosphatidylcholine acyltransferase 3 (LPCAT3) downregulation, which led to endoplasmic reticulum (ER) stress and hepatocyte injury. Supplementation with phosphatidylcholines significantly improved liver injury and ER stress induced by SCAP deletion. The activity of the SCAP/SREBP/LPCAT3 axis was found to be inversely associated with liver fibrosis severity in human NASH. SREBP inhibition also cooperated with impaired autophagy to trigger liver injury. Thus, excessively strong and broad lipogenesis inhibition was counterproductive for NASH therapy; this will have important clinical implications in NASH treatment.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Neoplasias Hepáticas , Proteínas de la Membrana , Enfermedad del Hígado Graso no Alcohólico , 1-Acilglicerofosfocolina O-Aciltransferasa/metabolismo , Animales , Carcinogénesis , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Fosfatidilcolinas/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo
9.
PLoS One ; 16(9): e0257090, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34516556

RESUMEN

Isocitrate dehydrogenase 1 and 2 (IDH1/2) mutations and their key effector 2-hydroxyglutarate (2-HG) have been reported to promote oncogenesis in various human cancers. To elucidate molecular mechanism(s) associated with IDH1/2 mutations, we established mouse embryonic fibroblasts (MEF) cells and human colorectal cancer cells stably expressing cancer-associated IDH1R132C or IDH2R172S, and analyzed the change in metabolic characteristics of the these cells. We found that IDH1/2 mutants induced intracellular 2-HG accumulation and inhibited cell proliferation. Expression profile analysis by RNA-seq unveiled that glucose transporter 1 (Glut1) was induced by the IDH1/2 mutants or treatment with 2-HG in the MEF cells. Consistently, glucose uptake and lactate production were increased by the mutants, suggesting the deregulation of glucose metabolism. Furthermore, PI3K/Akt/mTOR pathway and Hif1α expression were involved in the up-regulation of Glut1. Together, these results suggest that Glut1 is a potential target regulated by cancer-associated IDH1/2 mutations.


Asunto(s)
Trastornos del Metabolismo de la Glucosa/genética , Transportador de Glucosa de Tipo 1/metabolismo , Isocitrato Deshidrogenasa/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Mutación/genética , Neoplasias/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Proliferación Celular , Fibroblastos/metabolismo , Regulación Neoplásica de la Expresión Génica , Glucosa/metabolismo , Glutaratos/metabolismo , Glucólisis , Células HCT116 , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia , Espacio Intracelular/metabolismo , Ácido Láctico/metabolismo , Ratones Endogámicos C57BL , Proteínas Mutantes/metabolismo , Transducción de Señal
10.
J Hum Genet ; 66(11): 1053-1060, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33958709

RESUMEN

Lynch syndrome is a hereditary disease characterized by an increased risk of colorectal and other cancers. Germline variants in the mismatch repair (MMR) genes are responsible for this disease. Previously, we screened the MMR genes in colorectal cancer patients who fulfilled modified Amsterdam II criteria, and multiplex ligation-dependent probe amplification (MPLA) identified 11 structural variants (SVs) of MLH1 and MSH2 in 17 patients. In this study, we have tested the efficacy of long read-sequencing coupled with target enrichment for the determination of SVs and their breakpoints. DNA was captured by array probes designed to hybridize with target regions including four MMR genes and then sequenced using MinION, a nanopore sequencing platform. Approximately, 1000-fold coverage was obtained in the target regions compared with other regions. Application of this system to four test cases among the 17 patients correctly mapped the breakpoints. In addition, we newly found a deletion across an 84 kb region of MSH2 in a case without the pathogenic single nucleotide variants. These data suggest that long read-sequencing combined with hybridization-based enrichment is an efficient method to identify both SVs and their breakpoints. This strategy might replace MLPA for the screening of SVs in hereditary diseases.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales/genética , Homólogo 1 de la Proteína MutL/genética , Proteína 2 Homóloga a MutS/genética , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/complicaciones , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación de la Incompatibilidad de ADN/genética , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas/normas , Mutación de Línea Germinal/genética , Humanos , Masculino , Tamizaje Masivo , Homólogo 1 de la Proteína MutL/ultraestructura , Proteína 2 Homóloga a MutS/ultraestructura , Secuenciación de Nanoporos , Polimorfismo de Nucleótido Simple/genética , Conformación Proteica
11.
Gastroenterology ; 160(6): 2133-2148.e6, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33465373

RESUMEN

BACKGROUND & AIMS: Peribiliary glands (PBGs), clusters of epithelial cells residing in the submucosal compartment of extrahepatic bile ducts, have been suggested as biliary epithelial stem/progenitor cell niche; however, evidence to support this claim is limited because of a lack of PBG-specific markers. We therefore sought to identify PBG-specific markers to investigate the potential role of PBGs as stem/progenitor cell niches, as well as an origin of cancer. METHODS: We examined the expression pattern of the Wnt target gene Axin2 in extrahepatic bile ducts. We then applied lineage tracing to investigate whether Axin2-expressing cells from PBGs contribute to biliary regeneration and carcinogenesis using Axin2-CreERT mice. RESULTS: Wnt signaling activation, marked by Axin2, was limited to PBGs located in the periampullary region. Lineage tracing showed that Axin2-expressing periampullary PBG cells are capable of self-renewal and supplying new biliary epithelial cells (BECs) to the luminal surface. Additionally, the expression pattern of Axin2 and the mature ductal cell marker CK19 were mutually exclusive in periampullary region, and fate tracing of CK19+ luminal surface BECs showed gradual replacement by CK19- cells, further supporting the continuous replenishment of new BECs from PBGs to the luminal surface. We also found that Wnt signal enhancer R-spondin3 secreted from Myh11-expressing stromal cells, corresponding to human sphincter of Oddi, maintained the periampullary Wnt signal-activating niche. Notably, introduction of PTEN deletion into Axin2+ PBG cells, but not CK19+ luminal surface BECs, induced ampullary carcinoma whose development was suppressed by Wnt inhibitor. CONCLUSION: A specific cell population receiving Wnt-activating signal in periampullary PBGs functions as biliary epithelial stem/progenitor cells and also the cellular origin of ampullary carcinoma.


Asunto(s)
Ampolla Hepatopancreática , Proteína Axina/metabolismo , Carcinoma/patología , Neoplasias del Conducto Colédoco/patología , Células Epiteliales/patología , Células Madre/patología , Vía de Señalización Wnt , Ampolla Hepatopancreática/patología , Animales , Proteína Axina/genética , Conductos Biliares Extrahepáticos/metabolismo , Conductos Biliares Extrahepáticos/patología , Carcinogénesis/genética , Linaje de la Célula , Proliferación Celular , Células Epiteliales/metabolismo , Queratina-19/metabolismo , Ratones , Ratones Endogámicos C57BL , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Fosfohidrolasa PTEN/genética , Esfínter de la Ampolla Hepatopancreática/metabolismo , Células Madre/metabolismo , Trombospondinas/genética , Trombospondinas/metabolismo
12.
Cancer Sci ; 112(4): 1471-1480, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33506599

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is an increasingly common condition, affecting up to 25% of the population worldwide. NAFLD has been linked to several conditions, including hepatic inflammation, fibrosis, and hepatocellular carcinoma (HCC), however the role of NAFLD in cholangitis and the development of cholangiocellular carcinoma (CCC) remains poorly understood. This study investigated whether a high-fat diet (HFD) promotes cholangitis and the development of CCC in mice. We used liver-specific E-cadherin gene (CDH1) knockout mice, CDH1∆Liv , which develop spontaneous inflammation in the portal areas along with periductal onion skin-like fibrosis, similar to that of primary sclerosing cholangitis (PSC). An HFD or normal diet (ND) was fed to CDH1∆Liv mice for 7 mo. In addition, CDH1∆Liv mice were crossed with LSL-KrasG12D mice, fed an HFD, and assessed in terms of liver tumor development. The extent of cholangitis and number of bile ductules significantly increased in mice fed an HFD compared with ND-administered CDH1∆Liv mice. The numbers of Sox9 and CD44-positive stem cell-like cells were significantly increased in HFD mice. LSL-KrasG12D /CDH1∆Liv HFD mice exhibited increased aggressiveness along with the development of numerous HCC and CCC, whereas LSL-KrasG12D /CDH1∆Liv ND mice showed several macroscopic tumors with both HCC and CCC components. In conclusion, NAFLD exacerbates cholangitis and promotes the development of both HCC and CCC in mice.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/patología , Colangitis/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Animales , Antígenos CD/metabolismo , Neoplasias de los Conductos Biliares/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Colangiocarcinoma/metabolismo , Colangitis/metabolismo , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Inflamación/metabolismo , Inflamación/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/metabolismo
13.
Cell Death Dis ; 12(1): 99, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33468997

RESUMEN

While the significance of acquired genetic abnormalities in the initiation of hepatocellular carcinoma (HCC) has been established, the role of epigenetic modification remains unknown. Here we identified the pivotal role of histone methyltransferase G9a in the DNA damage-triggered initiation of HCC. Using liver-specific G9a-deficient (G9aΔHep) mice, we revealed that loss of G9a significantly attenuated liver tumor initiation caused by diethylnitrosamine (DEN). In addition, pharmacological inhibition of G9a attenuated the DEN-induced initiation of HCC. After treatment with DEN, while the induction of γH2AX and p53 were comparable in the G9aΔHep and wild-type livers, more apoptotic hepatocytes were detected in the G9aΔHep liver. Transcriptome analysis identified Bcl-G, a pro-apoptotic Bcl-2 family member, to be markedly upregulated in the G9aΔHep liver. In human cultured hepatoma cells, a G9a inhibitor, UNC0638, upregulated BCL-G expression and enhanced the apoptotic response after treatment with hydrogen peroxide or irradiation, suggesting an essential role of the G9a-Bcl-G axis in DNA damage response in hepatocytes. The proposed mechanism was that DNA damage stimuli recruited G9a to the p53-responsive element of the Bcl-G gene, resulting in the impaired enrichment of p53 to the region and the attenuation of Bcl-G expression. G9a deletion allowed the recruitment of p53 and upregulated Bcl-G expression. These results demonstrate that G9a allows DNA-damaged hepatocytes to escape p53-induced apoptosis by silencing Bcl-G, which may contribute to the tumor initiation. Therefore, G9a inhibition can be a novel preventive strategy for HCC.


Asunto(s)
Apoptosis/genética , Carcinoma Hepatocelular/genética , Daño del ADN/genética , Hepatocitos/metabolismo , Histona Metiltransferasas/genética , Neoplasias Hepáticas/genética , Proteína p53 Supresora de Tumor/metabolismo , Animales , Carcinoma Hepatocelular/patología , Silenciador del Gen , Humanos , Neoplasias Hepáticas/patología , Ratones
15.
J Hum Genet ; 64(12): 1187-1194, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31588121

RESUMEN

Lynch syndrome (LS) is an autosomal dominantly inherited disease predisposed to not only colorectal cancer but also other LS-related tumors. Although the clinical and genetic characteristics of LS in Western countries have been well characterized, the information of Japanese LS is limited. As a collaborative study of Japanese Society for Cancer of the Colon and Rectum (JSCCR), we registered colorectal cancer (CRC) patients who fulfilled the modified Amsterdam II criteria including gastric cancer as an LS-related tumor. Among 4030 CRC patients initially registered in this project, 85 patients (2.1%) fulfilled the modified criteria. An additional 26 patients who met the same criteria were enrolled in the analysis. We analyzed three major responsible genes, MLH1, MSH2, and MSH6 by direct sequencing, and further performed multiplex ligation-dependent probe amplification for MLH1 and MSH2. Consequently, we identified pathogenic variants in 64 of the 111 patients comprising of 34 patients in MLH1, 28 in MSH2, and 2 in MSH6. It is of note that large structural alterations were found in 17 patients. Among the 64 patients, 11 patients would not have been enrolled in the analysis if gastric cancer were not included in the modified criteria. In addition, 10 of the 64 variant carriers (15.6%) had medical history of gastric cancer. Furthermore, the standardized incidence ratio of gastric cancer in the LS patients to the Japanese population is estimated to be as high as 20.2. These data underscore the importance of gastric cancer in the diagnosis and healthcare of Japanese LS patients.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Gástricas/genética , Pueblo Asiatico/genética , Neoplasias Colorrectales/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias del Recto/genética
16.
Oncogene ; 38(32): 6051-6064, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31292489

RESUMEN

Impaired Wnt signaling pathway plays a crucial role in the development of colorectal cancer through activation of the ß-catenin/TCF7L2 complex. Although genes upregulated by Wnt/ß-catenin signaling have been intensively studied, the roles of downregulated genes are poorly understood. Previously, we reported that interferon-induced proteins with tetratricopeptide repeats 2 (IFIT2) was downregulated by the Wnt/ß-catenin signaling, and that the suppressed expression of IFIT2 conferred antiapoptotic property to colorectal cancer (CRC) cells. However, the mechanisms underlying how Wnt/ß-catenin signaling regulates IFIT2 remain to be elucidated. In this study, we have uncovered that the expression of IFIT2 is induced by IRF1, which is negatively regulated by the Wnt/ß-catenin signaling. In addition, we found that downregulation of IRF1 is mediated by its degradation through the ubiquitination-proteasome pathway, and that decreased activity of a deubiquitinase complex containing USP1 and UAF1 is involved in the degradation of IRF1 by Wnt/ß-catenin signaling. These data should provide better understanding of the Wnt signaling pathway and human carcinogenesis.


Asunto(s)
Apoptosis/fisiología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Factor 1 Regulador del Interferón/metabolismo , Proteolisis , Apoptosis/genética , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Células HEK293 , Humanos , Proteínas Nucleares/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitinación/genética , Vía de Señalización Wnt/fisiología , beta Catenina/metabolismo
17.
J Hum Genet ; 64(8): 729-740, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31089268

RESUMEN

Polymerase proofreading-associated polyposis (PPAP) is a disease caused by germline variations in the POLE and POLD1 genes that encode catalytic subunits of DNA polymerases. Studies of cancer genomes have identified somatic mutations in these genes, suggesting the importance of polymerase proofreading of DNA replication in suppressing tumorigenesis. Here, we identified a germline frameshift variation in the POLE gene (c.4191_4192delCT, p.Tyr1398*) in a case with multiple adenomatous polyps and three synchronous colon cancers. Interestingly, one of the colon cancers showed microsatellite instability-high (MSI-H) and another microsatellite stable. Immunohistochemical staining revealed that the MSI-H tumor cells lost the expression of MLH1 protein. Whole genome sequencing of the MSI-H tumor did not find pathogenic somatic mutations in mismatch repair genes but found frameshift mutations in the TET genes that catalyze 5-methylcytosine hydroxylation. Bisulfite sequencing of the tumor corroborated an increase in the number of hypermethylated regions including the MLH1 promoter. These data indicate that PPAP patients might develop MSI-positive tumors through epigenetic silencing of MLH1. These findings will contribute to comprehensive understanding of the molecular basis of tumors that involve deficiency of proofreading activity of DNA polymerases.


Asunto(s)
Neoplasias del Colon/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Metilación de ADN , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Inestabilidad de Microsatélites , Anciano , Alelos , Neoplasias del Colon/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Análisis Mutacional de ADN , ADN Polimerasa II/genética , ADN Polimerasa II/metabolismo , Femenino , Mutación del Sistema de Lectura , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genotipo , Mutación de Línea Germinal , Humanos , Inmunohistoquímica , Masculino , Estadificación de Neoplasias , Linaje , Fenotipo , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Proteínas Represoras/genética , Secuenciación Completa del Genoma
18.
J Pathol ; 247(1): 35-47, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30168144

RESUMEN

Chronic inflammation and intestinal metaplasia are strongly associated with gastric carcinogenesis. Kras activation and Pten deletion are observed in intestinal-type gastric cancer, and Cdh1 mutation is associated with diffuse-type gastric cancer. Although various mouse models of gastric carcinogenesis have been reported, few mouse lines enable gene manipulation selectively in the stomach. Here we established a Tff1-Cre bacterial artificial chromosome transgenic mouse line in an attempt to induce gene modification specifically in the gastric pit lineage. In the stomach, Tff1-Cre-mediated recombination was most evident in the pit lineage in the corpus and in entire antral glands; recombination was also observed in a few gastric chief and parietal cells. Outside the stomach, recombination was patchy throughout the intestines, and particularly frequently in the duodenum (Brunner glands), cecum, and proximal colon. In the stomachs of Tff1-Cre;LSL-KrasG12D mice, proliferating cell clusters expanded throughout the corpus glands, with foveolar cell expansion with ectopic Alcian blue-positive mucins, oxyntic atrophy, and pseudopyloric changes with spasmolytic polypeptide-expressing metaplasia; however, gastric cancer was not observed even at 12 months of age. Corpus-derived organoids from Tff1-Cre;LSL-KrasG12D mice exhibited accelerated growth and abnormal differentiation with a loss of chief and parietal cell markers. Tff1-Cre;Ptenflox/flox mice displayed similar changes to those seen in Tff1-Cre;LSL-KrasG12D mice, both with aberrant ERK activation within 3 months. In contrast, Tff1-Cre;Cdh1flox/flox mice initially showed signet ring-like cells that were rapidly lost with disruption of the mucosal surface, and later developed gastric epithelial shedding with hyperproliferation and loss of normal gastric lineages. Eventually, the glandular epithelium in Tff1-Cre;Cdh1flox/flox mice was completely replaced by squamous epithelium which expanded from the forestomach. Tff1-Cre mice offer an additional useful tool for studying gastric carcinogenesis both in vivo and in vitro. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Cadherinas/deficiencia , Proliferación Celular , Transformación Celular Neoplásica/metabolismo , Mucosa Gástrica/enzimología , Gastritis/enzimología , Fosfohidrolasa PTEN/deficiencia , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Neoplasias Gástricas/enzimología , Animales , Cadherinas/genética , Linaje de la Célula , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Cromosomas Artificiales Bacterianos , Mucinas Gástricas/genética , Mucinas Gástricas/metabolismo , Mucosa Gástrica/patología , Gastritis/genética , Gastritis/patología , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Integrasas/genética , Metaplasia , Ratones Transgénicos , Fosfohidrolasa PTEN/genética , Fenotipo , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Técnicas de Cultivo de Tejidos , Factor Trefoil-1/genética
19.
Cancer Sci ; 109(12): 4025-4032, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30289582

RESUMEN

Although liquid-based cytology (LBC) has increased the sensitivity of cytological diagnosis of endometrial cancer (EC) compared with conventional smear cytology, the sensitivity of LBC for the detection of EC is between 70% and 96% and remains unsatisfactory. In the present study, we compared the efficacy of LBC with liquid-based genetic diagnosis (LBGDx) by amplicon sequencing of five genes including PTEN, PIK3CA, CTNNB1, KRAS, and TP53 in 48 LBC subjects who underwent endometrial screening. Consequently, LBC classified 15 samples as "positive or suspicious for malignancy" and the 15 were later confirmed as EC. However, LBC failed to identify five cases who were diagnosed as EC by additional transvaginal ultrasound and endometrial curettage, indicating that the sensitivity of cytology alone was 75% (15/20). LBGDx identified 11 pathogenic PTEN variants in 10 subjects, six PIK3CA variants in nine, three CTNNB1 variants in five, two KRAS variants in four, and three TP53 variants in three. Collectively, at least one pathogenic variant was identified in 19 subjects, which included 17 EC (15 endometrioid carcinoma and 2 endometrial carcinosarcomas), and one cervical adenocarcinoma. However, LBGDx did not identify any pathogenic mutations in three of the 20 EC, indicating that the sensitivity of LBGDx alone was 85% (17/20). Although five EC were negative for malignancy by LBC and three were negative for pathogenic mutations by LBGDx, the combination of LBC and LBGDx would successfully diagnose all 20 EC. These data suggested that LBGDx is a useful strategy to improve the sensitivity of screening of EC by LBC.


Asunto(s)
Citodiagnóstico/métodos , ADN de Neoplasias/sangre , Neoplasias Endometriales/diagnóstico , Análisis de Secuencia de ADN/métodos , Fosfatidilinositol 3-Quinasa Clase I/genética , Neoplasias Endometriales/genética , Femenino , Variación Genética , Humanos , Fosfohidrolasa PTEN/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Sensibilidad y Especificidad , Proteína p53 Supresora de Tumor/genética , beta Catenina/genética
20.
Nat Immunol ; 19(10): 1071-1082, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30201994

RESUMEN

TLR3 is a sensor of double-stranded RNA that is indispensable for defense against infection with herpes simplex virus type 1 (HSV-1) in the brain. We found here that TLR3 was required for innate immune responses to HSV-1 in neurons and astrocytes. During infection with HSV-1, TLR3 recruited the metabolic checkpoint kinase complex mTORC2, which led to the induction of chemokines and trafficking of TLR3 to the cell periphery. Such trafficking enabled the activation of molecules (including mTORC1) required for the induction of type I interferons. Intracranial infection of mice with HSV-1 was exacerbated by impairment of TLR3 responses with an inhibitor of mTOR and was significantly 'rescued' by potentiation of TLR3 responses with an agonistic antibody to TLR3. These results suggest that the TLR3-mTORC2 axis might be a therapeutic target through which to combat herpes simplex encephalitis.


Asunto(s)
Encefalitis por Herpes Simple/inmunología , Diana Mecanicista del Complejo 2 de la Rapamicina/inmunología , Receptor Toll-Like 3/inmunología , Animales , Herpesvirus Humano 1 , Inmunidad Innata/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células 3T3 NIH
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