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1.
Small ; 20(6): e2305311, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37798936

RESUMEN

Structural engineering and hybridization of heterogeneous 2D materials can be effective for advanced supercapacitor. Furthermore, architectural design of electrodes particularly with vertical construction of structurally anisotropic graphene nanosheets, can significantly enhance the electrochemical performance. Herein, MXene-derived TiO2 nanocomposites hybridized with vertical graphene is synthesized via CO2 laser irradiation on MXene/graphene oxide nanocomposite film. Instantaneous photon energy by laser irradiation enables the formation of vertical graphene structures on nanocomposite films, presenting the controlled anisotropy in free-standing film. This vertical structure enables improved supercapacitor performance by forming an open structure, increasing the electrolyte-electrode interface, and creating efficient electron transport path. In addition, the effective oxidation of MXene nanosheets by instantaneous photon energy leads to the formation of rutile TiO2 . TiO2 nanoparticles directly generated on graphene enables the effective current path, which compensates for the low conductivity of TiO2 and enables the functioning of an effective supercapacitor by utilizing its pseudocapacitive properties. The resulting film exhibits excellent specific areal capacitance of 662.9 mF cm-2 at a current density of 5 mA cm-2 . The film also shows superb cyclic stability during 40 000 repeating cycles, maintaining high capacitance. Also, the pseudocapacitive redox reaction kinetics is evaluated, showing fast redox kinetics with potential for high-performance supercapacitor applications.

2.
J Nerv Ment Dis ; 209(1): 59-64, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33141783

RESUMEN

Past research has supported the positive association between prosuicide attitudes and suicidal behavior. The aim of the present study was to determine the factor structure of adolescents' attitudes toward suicide and to explore correlates associated with their attitudes. A questionnaire was distributed to 1292 adolescents at eight middle schools to assess their demographic information, clinical variables, and attitudes toward suicide. After factor analysis, we reached a four-factor solution of the attitudes toward suicide. Significantly more females, nonreligious adolescents, those with a lower socioeconomic status, those with higher levels of depressive symptoms, and those with a history of suicidal ideation/plans had more understanding attitudes toward suicide. Depressive adolescents were also more permissive and believed that suicides were unpreventable and that loneliness led to suicide. In conclusion, adolescents' attitudes toward suicide were significantly associated with not only various sociodemographic correlates but also the severity of depressive symptoms and their own experiences of suicidality.


Asunto(s)
Conducta del Adolescente , Actitud , Suicidio , Adolescente , Femenino , Humanos , Masculino , República de Corea , Factores de Riesgo , Instituciones Académicas , Factores Sexuales , Factores Socioeconómicos , Encuestas y Cuestionarios
3.
J Biol Chem ; 294(35): 12957-12974, 2019 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-31296660

RESUMEN

Transcriptional regulator KAISO plays a critical role in cell cycle arrest and apoptosis through modulation of p53 acetylation by histone acetyltransferase p300. KAISO potently stimulates apoptosis in cells expressing WT p53, but not in p53-mutant or p53-null cells. Here, we investigated how KAISO transcription is regulated by p53, finding four potential p53-binding sites (p53-responsive DNA elements; p53REs) located in a distal 5'-upstream regulatory element, intron 1, exon 2 coding sequence, and a 3'-UTR region. Transient transcription assays of pG5-p53RE-Luc constructs with various p53REs revealed that p53 activates KAISO (ZBTB33) transcription by acting on p53RE1 (-4326 to -4227) of the 5'-upstream region and on p53RE3 (+2929 to +2959) of the exon 2 coding region during early DNA damage responses (DDRs). ChIP and oligonucleotide pulldown assays further disclosed that p53 binds to the p53RE1 and p53RE3 sites. Moreover, ataxia telangiectasia mutated (ATM) or ATM-Rad3-related (ATR) kinase-mediated p53 phosphorylation at Ser-15 or Ser-37 residues activated KAISO transcription by binding its p53RE1 or p53RE3 sites during early DDR. p53RE1 uniquely contained three p53-binding half-sites, a structural feature important for transcriptional activation by phosphorylated p53 Ser-15·Ser-37. During the later DDR phase, a KAISO-mediated acetylated p53 form (represented by a p53QRQ acetyl-mimic) robustly activated transcription by acting on p53RE1 in which this structural feature is not significant, but it provided sufficient KAISO levels to confer a p53 "apoptotic code." These results suggest that the critical apoptosis regulator KAISO is a p53 target gene that is differently regulated by phosphorylated p53 or acetylated p53, depending on DDR stage.


Asunto(s)
Apoptosis , Factores de Transcripción/metabolismo , Activación Transcripcional , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Células Cultivadas , Humanos , Fosforilación , Factores de Transcripción/genética
4.
Biochem Biophys Res Commun ; 530(3): 588-596, 2020 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-32753315

RESUMEN

KLHL4 is a member of the KLHL protein family, many of whom bind the Cul3 E3 ligase, and mediate the ubiquitination of interacting proteins. The KLHL4 gene, localized on the X chromosome, associates with a disorder known as X-linked cleft palate (CPX). However, the biological functions of KLHL4 are largely unknown. In this study, microarray analysis of HEK293A embryonic kidney cells, expressing ectopic p53, showed a 3-fold increase of KLHL4 mRNA. Moreover, both KLHL4 mRNA and protein expression were elevated by p53 or DNA damage, suggesting that KLHL4 might be a p53 target gene. We also found that KLHL4 activates transcription of p21WAF/CDKN1A, a p53 target gene encoding a major negative regulator of the cell-cycle. KLHL4 interacted with p53 to increase its binding to p53 response element of the p21WAF/CDKN1A gene, resulting in transcriptional upregulation. Furthermore, we observed that KLHL4 can interact with the Cul3 ubiquitin ligase, to possibly play a role in ubiquitin-mediated proteasomal degradation, and Klhl4 knocked-out MEF mouse embryonic fibroblasts proliferated faster than WT MEF cells. These results suggest that KLHL4 upregulation by p53 may inhibit cell proliferation, by activating p21WAF/CDKN1A.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Proteínas del Citoesqueleto/genética , Proteína p53 Supresora de Tumor/genética , Proliferación Celular , Daño del ADN , Células HCT116 , Células HEK293 , Células HeLa , Humanos , ARN Mensajero/genética , Activación Transcripcional , Regulación hacia Arriba
5.
Biochem Biophys Res Commun ; 533(4): 1247-1254, 2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33051058

RESUMEN

The oncoprotein, c-Myc, not only promotes cell proliferation, but can also induce or sensitize cells to apoptosis. However, how c-Myc decides cell fate and which c-Myc downstream target genes are involved remain unknown. Previously, we showed that ZBTB5 (zinc finger and BTB domain-containing 5) is a proto-oncogene that stimulates cell proliferation. ZBTB5 represses p21/CDKN1A by competing with p53 and recruiting corepressor histone deacetylase complexes. Herein, we found that c-Myc directly activates the transcription of ZBTB5. In the absence of p53, ZBTB5 is acetylated at K597 by interacting with p300, and activates transcription of NOXA, which induces apoptosis. In contrast, in the presence of p53, ZBTB5 interacts with p53 and acetylation at ZBTB5 K597 is blocked. ZBTB5 without K597 acetylation interacts with mSin3A/HDAC1 to repress p21/CDKN1A transcription and promote cell proliferation. Cell fate decisions by c-Myc depend on ZBTB5, p53 and p300, and acetylation of ZBTB5 K597.


Asunto(s)
Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteína p53 Supresora de Tumor/fisiología , Acetilación , Apoptosis , Línea Celular , Proliferación Celular , Humanos , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-bcl-2/genética , Activación Transcripcional , Proteína p53 Supresora de Tumor/genética , Factores de Transcripción p300-CBP/metabolismo
6.
Biochim Biophys Acta ; 1849(9): 1170-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26183023

RESUMEN

KAISO, a member of the POK protein family, is induced by DNA-damaging agents to enhance apoptosis in a p53-dependent manner. Previously, we found that p53 interacts with KAISO, and acetylation of p53 lysine residues by p300 is modulated by KAISO. APAF1, the core molecule of the apoptosome, is transcriptionally activated by KAISO only in cells expressing p53, which binds to APAF1 promoter p53-response elements (p53REs). APAF1 transcriptional upregulation is further enhanced by KAISO augmentation of p53 binding to the APAF1 promoter distal p53RE#1 (bp, -765 to -739). Interestingly, a NF-κB response element, located close to the p53RE#1, mediates APAF1 transcriptional repression by affecting interaction between KAISO and p53. Ectopic RelA/p65 expression led to depletion of nuclear KAISO, with KAISO being mainly detected in the cytoplasm. RelA/p65 cytoplasmic sequestration of KAISO prevents its nuclear interaction with p53, decreasing APAF1 transcriptional activation by a p53-KAISO-p300 complex in cells exposed to genotoxic stresses. While KAISO enhances p53-dependent apoptosis by increasing APAF1 gene expression, RelA/p65 decreases apoptosis by blocking interaction between KAISO and p53. These findings have relevance to the phenomenon of cancer cells' diminished apoptotic capacity and the onset of chemotherapy resistance.


Asunto(s)
Factor Apoptótico 1 Activador de Proteasas/genética , Factor de Transcripción ReIA/fisiología , Factores de Transcripción/fisiología , Activación Transcripcional/fisiología , Proteína p53 Supresora de Tumor/fisiología , Línea Celular , Proliferación Celular/fisiología , Citoplasma/metabolismo , Humanos , Regiones Promotoras Genéticas , Unión Proteica , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
7.
Biochem Biophys Res Commun ; 462(2): 138-43, 2015 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-25935484

RESUMEN

Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-ß release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm³ increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versus radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/radioterapia , Indoles/administración & dosificación , Piridonas/administración & dosificación , Pirroles/administración & dosificación , Inhibidores de la Angiogénesis/administración & dosificación , Animales , Carcinoma Pulmonar de Lewis/metabolismo , Línea Celular Tumoral , Colágeno/metabolismo , Terapia Combinada , Ratones , Microvasos/efectos de los fármacos , Microvasos/patología , Microvasos/efectos de la radiación , Tolerancia a Radiación/efectos de los fármacos , Sunitinib , Factor de Crecimiento Transformador beta/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
8.
Radiat Environ Biophys ; 53(1): 93-101, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24305851

RESUMEN

The principal objective of this study was to assess the DNA damage in a normal cell line system after exposure to 60 Hz of extremely low frequency magnetic field (ELF-MF) and particularly in combination with various external factors, via comet assays. NIH3T3 mouse fibroblast cells, WI-38 human lung fibroblast cells, L132 human lung epithelial cells, and MCF10A human mammary gland epithelial cells were exposed for 4 or 16 h to a 60-Hz, 1 mT uniform magnetic field in the presence or absence of ionizing radiation (IR, 1 Gy), H(2)O(2) (50 µM), or c-Myc oncogenic activation. The results obtained showed no significant differences between the cells exposed to ELF-MF alone and the unexposed cells. Moreover, no synergistic or additive effects were observed after 4 or 16 h of pre-exposure to 1 mT ELF-MF or simultaneous exposure to ELF-MF combined with IR, H(2)O(2), or c-Myc activation.


Asunto(s)
Daño del ADN , Campos Electromagnéticos/efectos adversos , Peróxido de Hidrógeno/farmacología , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Expresión Génica , Humanos , Ratones , Oncogenes/genética , Radiación Ionizante
9.
Nat Nanotechnol ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956320

RESUMEN

Neuromodulation technologies are crucial for investigating neuronal connectivity and brain function. Magnetic neuromodulation offers wireless and remote deep brain stimulations that are lacking in optogenetic- and wired-electrode-based tools. However, due to the limited understanding of working principles and poorly designed magnetic operating systems, earlier magnetic approaches have yet to be utilized. Furthermore, despite its importance in neuroscience research, cell-type-specific magnetic neuromodulation has remained elusive. Here we present a nanomaterials-based magnetogenetic toolbox, in conjunction with Cre-loxP technology, to selectively activate genetically encoded Piezo1 ion channels in targeted neuronal populations via torque generated by the nanomagnetic actuators in vitro and in vivo. We demonstrate this cell-type-targeting magnetic approach for remote and spatiotemporal precise control of deep brain neural activity in multiple behavioural models, such as bidirectional feeding control, long-term neuromodulation for weight control in obese mice and wireless modulation of social behaviours in multiple mice in the same physical space. Our study demonstrates the potential of cell-type-specific magnetogenetics as an effective and reliable research tool for life sciences, especially in wireless, long-term and freely behaving animals.

10.
Biochim Biophys Acta Gene Regul Mech ; 1866(2): 194931, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37011832

RESUMEN

ZBTB7A overexpressed in many human cancers is a major oncogenic driver. ZBTB7A promotes tumorigenesis by regulating transcription of the genes involved in cell survival and proliferation, apoptosis, invasion, and migration/metastasis. One unresolved issue is the mechanism underlying the aberrant overexpression of ZBTB7A in cancer cells. Interestingly, inhibition of HSP90 decreased ZBTB7A expression in a variety of human cancer cells. ZBTB7A interacts with and is stabilized by HSP90. Inhibition of HSP90 by 17-AAG resulted in p53-dependent proteolysis of ZBTB7A via increased p53 expression and upregulation of the CUL3-dependent E3 ubiquitin ligase, KLHL20. Down-regulation of ZBTB7A resulted in the derepression of a major negative regulator of cell cycle progression, p21/CDKN1A. We discovered a new function of p53 regulating ZBTB7A expression through KLHL20-E3 ligase and proteasomal protein degradation system.


Asunto(s)
Proteínas de Unión al ADN , Neoplasias , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Neoplasias/genética , Proto-Oncogenes , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
11.
Cancer Res Treat ; 55(2): 385-399, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36915245

RESUMEN

PURPOSE: The current study provides national cancer statistics and their secular trends in Korea, including incidence, mortality, survival, and prevalence in 2020. Materials and Methods: Incidence, survival, and prevalence rates of cancer were calculated using the Korea National Cancer Incidence Database, from 1999 to 2020, with survival follow-up until December 31, 2021. Deaths from cancer were assessed using causes-of-death data obtained from Statistics Korea. RESULTS: The number of new cancer diagnoses in 2020 decreased by 9,218 cases (3.6%) compared to 2019. In 2020, newly diagnosed cancer cases and deaths from cancer were reported as 247,952 (age-standardized rate [ASR], 262.2 per 100,000) and 82,204 (ASR, 69.9 per 100,000), respectively. The overall cancer incidence rates increased by 3.3% annually from 1999 to 2012, and decreased by 5.0% annually from 2012 to 2015, thereafter, followed by nonsignificant changes. Cancer mortality rates have been decreasing since 2002, with more rapid decline in recent years. The 5-year relative survival between 2016 and 2020 was 71.5%, which contributed to prevalent cases reaching over 2.2 million in 2020. CONCLUSION: In 2020, the number of newly diagnosed cancer patients decreased due to the coronavirus disease 2019 pandemic, but the overall trend is on the rise. Cancer survival rates have improved over the past decades. As the number of cancer survivors increases, a comprehensive cancer control strategy should be implemented in line with the changing aspects of cancer statistics. The long-term impact of the coronavirus disease 2019 pandemic on cancer statistics needs to be investigated in the future.


Asunto(s)
COVID-19 , Neoplasias , Humanos , Incidencia , Prevalencia , COVID-19/epidemiología , Tasa de Supervivencia , República de Corea/epidemiología
12.
Angiogenesis ; 15(2): 229-42, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22350794

RESUMEN

Endothelial cell function is critical for angiogenic balance in both physiological and pathological conditions, such as wound healing and cancer, respectively. We report here that soluble heat shock protein beta-1 (HSPB1) is released primarily from endothelial cells (ECs), and plays a key role in regulating angiogenic balance via direct interaction with vascular endothelial growth factor (VEGF). VEGF-mediated phosphorylation of intracellular HSPB1 inhibited the secretion of HSPB1 and their binding activity in ECs. Interestingly, co-culture of tumor ECs with tumor cells decreased HSPB1 secretion from tumor ECs, suggesting that inhibition of HSPB1 secretion allows VEGF to promote angiogenesis. Additionally, neutralization of HSPB1 in a primary mouse sarcoma model promoted tumor growth, indicating the anti-angiogenic role of soluble HSPB1. Overexpression of HSPB1 by HSPB1 adenovirus was sufficient to suppress lung metastases of CT26 colon carcinoma in vivo, while neutralization of HSPB1 promoted in vivo wound healing. While VEGF-induced regulation of angiogenesis has been studied extensively, these findings illustrate the key contribution of HSPB1-VEGF interactions in the balance between physiological and pathological angiogenesis.


Asunto(s)
Neoplasias del Colon/metabolismo , Células Endoteliales/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Neovascularización Fisiológica , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Línea Celular Tumoral , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Células Endoteliales/patología , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico/genética , Humanos , Ratones , Ratones Transgénicos , Chaperonas Moleculares , Proteínas de Neoplasias/genética , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Factor A de Crecimiento Endotelial Vascular/genética , Cicatrización de Heridas/genética
13.
Mol Cancer Res ; 20(8): 1305-1319, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35394541

RESUMEN

KRAS mutation in colorectal cancer is associated with aggressive tumor behavior through increased invasiveness and higher rates of lung metastases, but the biological mechanisms behind these features are not fully understood. In this study, we show that KRAS-mutant colorectal cancer upregulates integrin α6ß4 through ERK/MEK signaling. Knocking-out integrin ß4 (ITGB4) specifically depleted the expression of integrin α6ß4 and this resulted in a reduction in the invasion and migration ability of the cancer cells. We also observed a reduction in the number and area of lung metastatic foci in mice that were injected with ITGB4 knockout KRAS-mutant colorectal cancer cells compared with the mice injected with ITGB4 wild-type KRAS-mutant colorectal cancer cells, while no difference was observed in liver metastases. Inhibiting integrin α6ß4 in KRAS-mutant colorectal cancer could be a potential therapeutic target to diminish the KRAS-invasive phenotype and associated pulmonary metastasis rate. IMPLICATIONS: Knocking-out ITGB4, which is overexpressed in KRAS-mutant colorectal cancer and promotes tumor aggressiveness, diminishes local invasiveness and rates of pulmonary metastasis.


Asunto(s)
Neoplasias Colorrectales , Integrina beta4 , Neoplasias Pulmonares , Animales , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Integrina alfa6beta4/genética , Integrina alfa6beta4/metabolismo , Integrina beta4/genética , Integrina beta4/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Ratones , Invasividad Neoplásica/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo
14.
Cell Rep Methods ; 2(12): 100353, 2022 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-36590695

RESUMEN

We describe a mouse model of rectal cancer (RC) involving rapid tumor organoid engraftment via orthotopic transplantation in an immunocompetent setting. This approach uses simple mechanical disruption to allow engraftment, avoiding the use of dextran sulfate sodium. The resulting RC tumors invaded from the mucosal surface and metastasized to distant organs. Histologically, the tumors closely resemble human RC and mirror remodeling of the tumor microenvironment in response to radiation. This murine RC model thus recapitulates key aspects of human RC pathogenesis and presents an accessible approach for more physiologically accurate, preclinical efficacy studies.


Asunto(s)
Neoplasias del Recto , Ratones , Humanos , Animales , Neoplasias del Recto/radioterapia , Microambiente Tumoral
15.
Nat Cell Biol ; 24(12): 1739-1753, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36456828

RESUMEN

Adherens junctions (AJs) create spatially, chemically and mechanically discrete microdomains at cellular interfaces. Here, using a mechanogenetic platform that generates artificial AJs with controlled protein localization, clustering and mechanical loading, we find that AJs also organize proteolytic hotspots for γ-secretase with a spatially regulated substrate selectivity that is critical in the processing of Notch and other transmembrane proteins. Membrane microdomains outside of AJs exclusively organize Notch ligand-receptor engagement (LRE microdomains) to initiate receptor activation. Conversely, membrane microdomains within AJs exclusively serve to coordinate regulated intramembrane proteolysis (RIP microdomains). They do so by concentrating γ-secretase and primed receptors while excluding full-length Notch. AJs induce these functionally distinct microdomains by means of lipid-dependent γ-secretase recruitment and size-dependent protein segregation. By excluding full-length Notch from RIP microdomains, AJs prevent inappropriate enzyme-substrate interactions and suppress spurious Notch activation. Ligand-induced ectodomain shedding eliminates size-dependent segregation, releasing Notch to translocate into AJs for processing by γ-secretase. This mechanism directs radial differentiation of ventricular zone-neural progenitor cells in vivo and more broadly regulates the proteolysis of other large cell-surface receptors such as amyloid precursor protein. These findings suggest an unprecedented role of AJs in creating size-selective spatial switches that choreograph γ-secretase processing of multiple transmembrane proteins regulating development, homeostasis and disease.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide , Secretasas de la Proteína Precursora del Amiloide/genética , Ligandos
16.
Nat Med ; 28(8): 1646-1655, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35970919

RESUMEN

The incidence of rectal cancer is increasing in patients younger than 50 years. Locally advanced rectal cancer is still treated with neoadjuvant radiation, chemotherapy and surgery, but recent evidence suggests that patients with a complete response can avoid surgery permanently. To define correlates of response to neoadjuvant therapy, we analyzed genomic and transcriptomic profiles of 738 untreated rectal cancers. APC mutations were less frequent in the lower than in the middle and upper rectum, which could explain the more aggressive behavior of distal tumors. No somatic alterations had significant associations with response to neoadjuvant therapy in a treatment-agnostic manner, but KRAS mutations were associated with faster relapse in patients treated with neoadjuvant chemoradiation followed by consolidative chemotherapy. Overexpression of IGF2 and L1CAM was associated with decreased response to neoadjuvant therapy. RNA-sequencing estimates of immune infiltration identified a subset of microsatellite-stable immune hot tumors with increased response and prolonged disease-free survival.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Quimioradioterapia , Genómica , Humanos , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/terapia , Estudios Retrospectivos , Transcriptoma/genética , Resultado del Tratamiento
17.
Exp Mol Med ; 53(5): 917-932, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34017061

RESUMEN

Zbtb7c is a proto-oncoprotein that controls the cell cycle and glucose, glutamate, and lipid metabolism. Zbtb7c expression is increased in the liver and white adipose tissues of aging or high-fat diet-fed mice. Knockout or knockdown of Zbtb7c gene expression inhibits the adipocyte differentiation of 3T3-L1 cells and decreases adipose tissue mass in aging mice. We found that Zbtb7c was a potent transcriptional repressor of SIRT1 and that SIRT1 was derepressed in various tissues of Zbtb7c-KO mice. Mechanistically, Zbtb7c interacted with p53 and bound to the proximal promoter p53RE1 and p53RE2 to repress the SIRT1 gene, in which p53RE2 was particularly critical. Zbtb7c induced p53 to interact with the corepressor mSin3A-HADC1 complex at p53RE. By repressing the SIRT1 gene, Zbtb7c increased the acetylation of Pgc-1α and Pparγ, which resulted in repression or activation of Pgc-1α or Pparγ target genes involved in lipid metabolism. Our study provides a molecular target that can overexpress SIRT1 protein in the liver, pancreas, and adipose tissues, which can be beneficial in the treatment of diabetes, obesity, longevity, etc.


Asunto(s)
Envejecimiento/genética , Envejecimiento/metabolismo , Dieta Alta en Grasa , Péptidos y Proteínas de Señalización Intracelular/genética , Obesidad/etiología , Obesidad/metabolismo , Sirtuina 1/genética , Células 3T3-L1 , Adipocitos/citología , Adipocitos/metabolismo , Animales , Biomarcadores , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Regulación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Metabolismo de los Lípidos , Ratones , Ratones Noqueados , Obesidad/patología , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Unión Proteica , Elementos de Respuesta , Sirtuina 1/metabolismo , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
18.
Int J Radiat Oncol Biol Phys ; 109(2): 553-566, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32942004

RESUMEN

PURPOSE: Radiation-induced pulmonary fibrosis (RIPF) is a long-term side effect of thoracic radiation therapy. Hypoxia-induced vascular endothelial mesenchymal transition (EndMT) can occur during the development of RIPF. Here, we examined the direct contribution of endothelial HIF-1α (EC-HIF1α) on RIPF. METHODS AND MATERIALS: An inducible Cre-lox-mediated endothelial Hif1a deletion mouse line was used to evaluate the potential of HIF-1α inhibition to suppress RIPF. To evaluate the effects of a pharmacologic HIF-1α inhibitor on RIPF after image guided radiation therapy (IGRT) for spontaneous lung adenocarcinoma, we generated conditional tdTomato; K-RasG12D; and p53 flox/flox mice to facilitate tracking of tumor cells expressing tdTomato. RESULTS: We found that vascular endothelial-specific HIF-1α deletion shortly before radiation therapy inhibited the progression of RIPF along with reduced EndMT, whereas prolonged deletion of endothelial HIF-1α before irradiation did not. Moreover, we revealed that postirradiation treatment with the novel HIF-1α inhibitor, 2-methoxyestradiol (2-ME) could efficiently inhibit RIPF and EndMT. In addition, IGRT using primary mouse models of non-small cell lung cancer showed that combined treatment of 2-ME with ablative high-dose radiation therapy efficiently inhibited RIPF and the growth of both multifocal and single tumors, concomitantly reducing radiation-induced EndMT of normal as well as tumor regions. CONCLUSION: These results suggest that a negative regulator of HIF-1α-mediated EndMT, such as 2-ME, may serve as a promising inhibitor of RIPF in radiation therapy.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Fibrosis Pulmonar/tratamiento farmacológico , Traumatismos por Radiación/tratamiento farmacológico , Radioterapia Guiada por Imagen/efectos adversos , 2-Metoxiestradiol/farmacología , Animales , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Línea Celular Tumoral , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Ratones , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/metabolismo , Traumatismos por Radiación/etiología , Traumatismos por Radiación/metabolismo
19.
Soa Chongsonyon Chongsin Uihak ; 32(3): 104-111, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34285635

RESUMEN

OBJECTIVES: Adolescent suicide is a serious national issue in Korea. Recently, life satisfaction has been recognized as a major factor related to this issue. The main purpose of this study was to identify the domains of life satisfaction that affect suicidal behavior in adolescence. METHODS: Data were collected from eight middle schools in Incheon, Korea. A total of 1297 students answered questions regarding their demographic characteristics, happiness, self-related life satisfaction domains (appearance, leisure time, physical health, and mental health), depressive symptoms, and suicidal behavior. RESULTS: In the Spearman correlation analysis, female sex, perceived socioeconomic status (SES), happiness, and all four self-related satisfaction scores showed significant correlations with depression and suicidality. Multivariate regression analysis suggested that suicidality was significantly affected by perceived SES, satisfaction with appearance, mental health satisfaction, and depression. Finally, depression was identified as a partial mediator of the association between mental health satisfaction and suicidality, and a complete mediator of the association between female sex and suicidality. CONCLUSION: Perceived SES, satisfaction with appearance, and mental health satisfaction significantly affected students' suicidality, with or without the effect of depression. Health authorities, educators, and family members must be aware of this to identify adolescents at suicide risk earlier.

20.
Mol Oncol ; 15(10): 2766-2781, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33817986

RESUMEN

Somatic mutations in the KRAS oncogene are associated with poor outcomes in locally advanced rectal cancer but the underlying biologic mechanisms are not fully understood. We profiled mRNA in 76 locally advanced rectal adenocarcinomas from patients that were enrolled in a prospective clinical trial and investigated differences in gene expression between KRAS mutant (KRAS-mt) and KRAS-wild-type (KRAS-wt) patients. We found that KRAS-mt tumors display lower expression of genes related to the tumor stroma and remodeling of the extracellular matrix. We validated our findings using samples from The Cancer Genome Atlas (TCGA) and also by performing immunohistochemistry (IHC) and immunofluorescence (IF) in orthogonal cohorts. Using in vitro and in vivo models, we show that oncogenic KRAS signaling within the epithelial cancer cells modulates the activity of the surrounding fibroblasts in the tumor microenvironment.


Asunto(s)
Proteínas Proto-Oncogénicas p21(ras) , Neoplasias del Recto , Ensayos Clínicos como Asunto , Matriz Extracelular , Fibroblastos/patología , Humanos , Mutación/genética , Estudios Prospectivos , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias del Recto/genética , Neoplasias del Recto/patología , Microambiente Tumoral
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