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1.
Nature ; 621(7980): 711-715, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37758892

RESUMEN

The nearby radio galaxy M87 offers a unique opportunity to explore the connections between the central supermassive black hole and relativistic jets. Previous studies of the inner region of M87 revealed a wide opening angle for the jet originating near the black hole1-4. The Event Horizon Telescope resolved the central radio source and found an asymmetric ring structure consistent with expectations from general relativity5. With a baseline of 17 years of observations, there was a shift in the jet's transverse position, possibly arising from an 8- to 10-year quasi-periodicity3. However, the origin of this sideways shift remains unclear. Here we report an analysis of radio observations over 22 years that suggests a period of about 11 years for the variation in the position angle of the jet. We infer that we are seeing a spinning black hole that induces the Lense-Thirring precession of a misaligned accretion disk. Similar jet precession may commonly occur in other active galactic nuclei but has been challenging to detect owing to the small magnitude and long period of the variation.

2.
Exp Dermatol ; 33(5): e15088, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685820

RESUMEN

Recently, the pathomechanisms of keloids have been extensively researched using transcriptomic analysis, but most studies did not consider the activity of keloids. We aimed to profile the transcriptomics of keloids according to their clinical activity and location within the keloid lesion, compared with normal and mature scars. Tissue samples were collected (keloid based on its activity (active and inactive), mature scar from keloid patients and normal scar (NS) from non-keloid patients). To reduce possible bias, all keloids assessed in this study had no treatment history and their location was limited to the upper chest or back. Multiomics assessment was performed by using single-cell RNA sequencing and multiplex immunofluorescence. Increased mesenchymal fibroblasts (FBs) was the main feature in keloid patients. Noticeably, the proportion of pro-inflammatory FBs was significantly increased in active keloids compared to inactive ones. To explore the nature of proinflammatory FBs, trajectory analysis was conducted and CCN family associated with mechanical stretch exhibited higher expression in active keloids. For vascular endothelial cells (VECs), the proportion of tip and immature cells increased in keloids compared to NS, especially at the periphery of active keloids. Also, keloid VECs highly expressed genes with characteristics of mesenchymal activation compared to NS, especially those from the active keloid center. Multiomics analysis demonstrated the distinct expression profile of active keloids. Clinically, these findings may provide the future appropriate directions for development of treatment modalities of keloids. Prevention of keloids could be possible by the suppression of mesenchymal activation between FBs and VECs and modulation of proinflammatory FBs may be the key to the control of active keloids.


Asunto(s)
Fibroblastos , Queloide , Queloide/patología , Queloide/metabolismo , Humanos , Fibroblastos/metabolismo , Transcriptoma , Células Endoteliales/metabolismo , Femenino , Adulto , Masculino , Perfilación de la Expresión Génica , Análisis de la Célula Individual
3.
Phonetica ; 78(5-6): 435-465, 2021 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-34655514

RESUMEN

The present study examines the phonetic and phonological status of vowel reduction in Brazilian Portuguese. In order to compare the effects of duration and metrical structure, we tested the influence of duration on the realization of /a/ in five prosodic positions: word-initial pretonic, word-medial pretonic, tonic, word-medial posttonic, and word-final posttonic. The results revealed that, while both phonetic duration and prosodic position had effects on F1 values for /a/, the categorical effect of prosodic position was much stronger and more reliable. In particular, F1 values for /a/ were best predicted by a two-way distinction between posttonic and non-posttonic syllable positions. Correlations between a vowel's duration and its F1 frequency were statistically significant but generally weak in all positions. We argue that these findings suggest that vowel reduction in Brazilian Portuguese primarily reflects phonological patterning rather than phonetic undershoot, although there was also evidence for some amount of undershoot. Brazilian Portuguese can therefore be said to have a mixed system of phonological and phonetic reduction. The present study discusses the results in the context of Brazilian Portuguese metrical organization, sound change, and the relation between phonetics and phonology.


Asunto(s)
Fonética , Procedimientos de Cirugía Plástica , Brasil , Cafeína , Humanos , Lenguaje
4.
Ann Vasc Surg ; 66: 554-565, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31706994

RESUMEN

BACKGROUND: The association between oxidized low-density lipoprotein (OxLDL) and plaque instability in coronary and carotid artery disease is well established. However, the association between OxLDL and the histologic changes of plaque in peripheral artery disease has not been clearly elucidated. This study aims to investigate the association between plasma OxLDL and histologic plaque instability in patients with peripheral artery disease. METHODS: Prospectively obtained plaques from 48 patients who underwent endovascular atherectomy (n = 20), surgical endarterectomy (n = 9), or bypass surgery (n = 19) for treatment of atherosclerotic femoropopliteal artery disease were evaluated for histologic fibrosis, sclerosis, calcification, necrosis, cholesterol cleft, and foamy macrophages using hematoxylin and eosin, oil red O, and immunohistochemical staining. Unstable plaques were defined as plaques that were positive for foamy macrophages and with lipid content of more than 10% of the total plaque area. Plasma OxLDL levels were measured using an enzyme-linked immunosorbent assay (Mercodia AB, Uppsala, Sweden). RESULTS: Of the 48 patients, 26 (54%) had unstable plaques. The unstable plaque group was younger, had fewer angiographic total occlusions, less calcification, and more CD68-positive and LOX-1-positive cells than the stable plaque group. Plasma OxLDL levels were significantly higher in the unstable plaque group than in the stable plaque group (57.4 ± 13.9 vs. 47.2 ± 13.6 U/L, P = 0.014). Multivariate analysis revealed that plasma OxLDL level, smoking, angiographic nontotal occlusion, and statin nonuse were independent predictors of unstable plaque. CONCLUSIONS: Among patients with peripheral artery disease, the histologic instability of femoropopliteal plaque was independently associated with high plasma OxLDL, smoking, nontotal occlusion, and statin nonuse. Further large-scale studies are necessary to evaluate the role of noninvasive OxLDL measurement for predicting plaque instability and future adverse vascular event.


Asunto(s)
Lipoproteínas LDL/sangre , Enfermedad Arterial Periférica/sangre , Enfermedad Arterial Periférica/patología , Placa Aterosclerótica , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/terapia , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , República de Corea , Factores de Riesgo , Rotura Espontánea , Regulación hacia Arriba
5.
Gastroenterology ; 155(3): 799-814.e13, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29775598

RESUMEN

BACKGROUND & AIMS: Markers of the epithelial-to-mesenchymal transition (EMT) in gastric tumor tissues are associated with poor patient outcomes. We performed a screen to identify pharmacologic compounds that kill gastric cancer cells with EMT-associated gene expression patterns and investigate their mechanisms. METHODS: We identified 29 gastric cancer cell lines with a gene expression signature previously associated with an EMT subtype, based on data from RNA sequence analyses, and confirmed the mesenchymal phenotypes of 7 lines (Hs746T, SNU1750, MKN1, SK4, SNU484, SNU668, and YCC11), based on invasive activity and protein markers. We screened 1,345 compounds for their ability to kill cells with the EMT signature compared with cell lines without this pattern. We tested the effects of identified compounds in BALB/c nude mice bearing GA077 tumors; mice were given intraperitoneal injections of the compound or vehicle (control) twice daily for 24 days and tumor growth was monitored. Proteins associated with the toxicity of the compounds were overexpressed in MKN1 and SNU484 cells or knocked down in MKN45 and SNU719 using small interfering RNAs. We performed immunohistochemical analyses of 942 gastric cancer tissues and investigated associations between EMT markers and protein expression patterns. RESULTS: The nicotinamide phosphoribosyltransferase inhibitor FK866 killed 6 of 7 gastric cancer cell lines with EMT-associated gene expression signatures but not gastric cancer cells without this signature. The 6 EMT-subtype gastric cell lines expressed significantly low levels of nicotinic acid phosphoribosyltransferase (NAPRT), which makes the cells hypersensitive to nicotinamide phosphoribosyltransferase inhibition. Gastric cell lines that expressed higher levels of NAPRT, regardless of EMT markers, were sensitized to FK866 after knockdown of NAPRT, whereas overexpression of NAPRT in deficient EMT cell lines protected them from FK866-mediated toxicity. Administration of FK866 to nude mice with tumors grown from GA077 cells (human gastric cancer tumors of the EMT subtype) led to tumor regression in 2 weeks; FK866 did not affect tumors grown from MKN45 cells without the EMT expression signature. Loss of NAPRT might promote the EMT, because it stabilizes ß-catenin. We correlated the EMT gene expression signature with lower levels of NAPRT in 942 gastric tumors from patients; we also found lower levels of NAPRT mRNA in colorectal, pancreatic, and lung adenocarcinoma tissues with the EMT gene expression signature. CONCLUSIONS: FK866 selectively kills gastric cancer cells with an EMT gene expression signature by inhibiting nicotinamide phosphoribosyltransferase in cells with NAPRT deficiency. Loss of NAPRT expression, frequently through promoter hypermethylation, is observed in many gastric tumors of the EMT subtype. FK866 might be used to treat patients with tumors of this subtype.


Asunto(s)
Acrilamidas/farmacología , Antineoplásicos/farmacología , Citocinas/antagonistas & inhibidores , Transición Epitelial-Mesenquimal/efectos de los fármacos , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Piperidinas/farmacología , Neoplasias Gástricas/tratamiento farmacológico , Animales , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/genética , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Interferente Pequeño/administración & dosificación , Neoplasias Gástricas/genética
6.
Immunol Invest ; 47(1): 89-100, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29099628

RESUMEN

BACKGROUND: CD1d-dependent invariant natural killer (iNKT) cells are found as either CD4 single positive (SP) or CD4/CD8 double negative (DN) cells in mice. The size of the CD8+ iNKT population is extremely small. It is known that CD1d expression on developing thymocytes is sufficient for iNKT development and co-receptor choice, which is driven by Th-POK expression. This study aimed to examine the factors involved in the CD4/CD8 co-receptor choice of iNKT cells in addition to Th-POK-driven silencing of CD8 expression. METHODS: In this study, we compared iNKT cells of wild-type (WT) mice with those of transgenic mice in which CD1d expression is restricted to developing thymocytes by the proximal Lck (pLCK) promoter. CD8 positive iNKT cell population were analyzed by flow cytometry. RESULTS: We found that there was a substantial population of CD8+ iNKT cells in the thymus and spleen of transgenic mice, and these cells are negatively selected in between Stage 2 and Stage 3 of their developmental program by the CD1d expressed on Thymic epithelial cell (TEC) and Dendritic cells in WT mice. CONCLUSION: We conclude that TEC expression of CD1d in the murine thymus contributed to co-receptor choice of iNKT cells, in addition to Th-POK-driven silencing of CD8. Therefore, mostly CD4 SP and DN iNKT cells are produced under normal physiological conditions in mice.


Asunto(s)
Células Dendríticas/inmunología , Células Epiteliales/inmunología , Células T Asesinas Naturales/fisiología , Timo/patología , Animales , Antígenos CD1d/genética , Antígenos CD8/metabolismo , Células Cultivadas , Selección Clonal Mediada por Antígenos , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T alfa-beta/genética
7.
Expert Rev Proteomics ; 13(10): 929-939, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27599289

RESUMEN

INTRODUCTION: Despite extreme genetic heterogeneity, tumors often show similar alterations in the expression, stability, and activation of proteins important in oncogenic signaling pathways. Thus, classifying tumor samples according to shared proteomic features may help facilitate the identification of cancer subtypes predictive of therapeutic responses and prognostic for patient outcomes. Meanwhile, understanding mechanisms of intrinsic and acquired resistance to anti-cancer therapies at the protein level may prove crucial to devising reversal strategies. Areas covered: Herein, we review recent advances in quantitative proteomic technology and their applications in studies to identify intrinsic tumor subtypes of various tumors, to illuminate mechanistic aspects of pharmacological and oncogenic adaptations, and to highlight interaction targets for anti-cancer compounds and cancer-addicted proteins. Expert commentary: Quantitative proteomic technologies are being successfully employed to classify tumor samples into distinct intrinsic subtypes, to improve existing DNA/RNA based classification methods, and to evaluate the activation status of key signaling pathways.

8.
Circ J ; 80(12): 2513-2519, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27829592

RESUMEN

BACKGROUND: Coronary revascularization has been shown to induce left ventricular (LV) reverse remodeling (RR). The serial morphologic changes in enhanced necrotic tissue during RR on cardiac magnetic resonance imaging (CMR) have not been investigated.Methods and Results:This retrospective study included 26 patients with severe LV systolic dysfunction (ejection fraction [EF], <35% on echocardiography) who underwent CMR before and >6 months after surgical revascularization. Of 26 patients, 20 had a reduction of ≥10% in end-diastolic and end-systolic volumes (classified as RR group). The RR group had improvement in EF after revascularization (28.8±6.6% vs. 40.6±7.8%, P<0.0001), and no change in absolute infarct mass (17.3±10.9 g vs. 17.5±10.4 g, P=0.8), but an increase in relative infarct mass (21.0±13.7% vs. 26.5±19.4%, P=0.01) due to reduction of myocardial mass after revascularization. Significant increase in regional transmural extent (30.3±21.6 vs. 42.6±22.8, P<0.0001) and in thickness of enhanced tissue (4.2±1.5 mm vs. 5.9±1.8 mm, P<0.0001) was found in the RR group. No significant differences were observed in any of the variables in the non-RR group. CONCLUSIONS: In patients with chronic myocardial ischemic dysfunction, significant volume reduction after revascularization led to significant increase in regional transmural extent of the enhanced area without a change in absolute infarct mass, on CMR. (Circ J 2016; 80: 2513-2519).


Asunto(s)
Procedimientos Endovasculares , Imagen por Resonancia Magnética , Isquemia Miocárdica , Complicaciones Posoperatorias , Disfunción Ventricular Izquierda , Remodelación Ventricular , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/fisiopatología , Isquemia Miocárdica/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología
9.
Cerebrovasc Dis ; 38(4): 254-61, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25401484

RESUMEN

BACKGROUND: Multiple hypointense vessels (MHV) on susceptibility-weighted imaging (SWI) are frequently observed in patients with acute cerebral ischemia, but their implication has not been clearly established. To elucidate the clinical significance of MHV on SWI, we investigated the association of MHV on SWI with clinical data and other MR markers in patients with acute ischemic stroke. METHODS: We enrolled acute stroke patients with internal carotid or proximal middle cerebral artery occlusion who underwent MRI including SWI within 3 days from stroke onset. Baseline clinical data were reviewed. Stroke severity was measured by the National Institutes of Health Stroke Scale (NIHSS). We graded the degree of MHV on SWI as four groups of none, subtle, relative, or extensive by the modified Alberta Stroke Program Early CT Scan (ASPECTS) system. To evaluate the degree of collateral flow, distal hyperintense vessels (DHV) on FLAIR and vessels on post-contrast time-of-flight MR angiography (TOF MRA) source images were graded respectively as 3 groups: none/subtle/prominent and poor/moderate/good. Diffusion and perfusion lesion volume and diffusion-perfusion mismatch (DPM) ratio were measured in all patients. We analyzed the association of the degree of MHV on SWI with clinical data and MR markers. RESULTS: Eighty patients were included in the study. The mean MR time from stroke onset was 12.4 h (range 0.5-63.0). There is no difference in MR time from stroke onset between groups of MHV on SWI. MHV were observed in 68 (85%) of 80 patients: none in 12, subtle in 11, relative in 13, and extensive in 44. There were no statistically significant associations between MHV on SWI and vascular risk factors. Patients with more extensive MHV on SWI had a smaller diffusion volume (p < 0.001), larger DPM (p < 0.001), and lower initial NIHSS scores (p = 0.022). Prominent DHV was presented in 29 of 44 patients with extensive MHV (p < 0.001). Good collateral flow on TOF MRA source images was presented in 37 of 44 patients with extensive MHV (p < 0.001). CONCLUSIONS: More extensive MHV on SWI in acute ischemic stroke is associated with lower initial NIHSS scores, smaller diffusion lesion volume, better collateral flow, and larger DPM. Our results show the possibility that MHV on SWI may be a useful surrogate marker for predicting increased oxygen extraction fraction and diffusion-perfusion mismatch in acute ischemic hemisphere.


Asunto(s)
Isquemia Encefálica/diagnóstico , Arterias Cerebrales/metabolismo , Arterias Cerebrales/fisiopatología , Circulación Cerebrovascular , Circulación Colateral , Imagen de Difusión por Resonancia Magnética , Infarto de la Arteria Cerebral Media/diagnóstico , Angiografía por Resonancia Magnética , Consumo de Oxígeno , Imagen de Perfusión/métodos , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatología , Evaluación de la Discapacidad , Femenino , Humanos , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/fisiopatología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo
10.
J Stroke Cerebrovasc Dis ; 23(7): 1865-70, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24809669

RESUMEN

BACKGROUND: Spontaneous isolated posterior inferior cerebellar artery dissection (PICAD) is a very rare cause of ischemic stroke. Clinical and radiologic features of ischemic type of isolated spontaneous PICAD are not well established. METHODS: We consecutively enrolled patients who had spontaneous isolated PICAD confirmed by digital subtraction cerebral angiography. Clinical manifestation, magnetic resonance imaging (MRI), and angiography were analyzed. RESULTS: Seven patients were diagnosed as ischemic type of spontaneous isolated PICAD. Patients experienced an occipital headache, followed by vertigo, postural imbalance, or Wallenberg syndrome. Six showed medullar, unilateral, or bilateral cerebellar infarctions on diffusion-weighted imaging (DWI). One presented with transient cerebellar ischemia and negative on DWI. T1-weighted imaging showed high signal intensity in posterior inferior cerebellar artery in only 1 patient. Susceptibility-weighted imaging (SWI) revealed hypointense signal with blooming effect in posterior inferior cerebellar artery in 5 patients. The modified Rankin Scale score at 3 months was 0 or 1 in all patients. CONCLUSIONS: Clinical manifestations in ischemic type of spontaneous isolated PICAD were similar to those of intracranial vertebral artery dissection. Clinical course was relatively stable and benign. SWI was more helpful to suspect abnormality of posterior inferior cerebellar artery than conventional MRI or magnetic resonance angiography in our small series. Cerebral angiography is recommended in patients with clinically suspected spontaneous isolated PICAD for definite diagnosis.


Asunto(s)
Isquemia Encefálica/etiología , Enfermedades Cerebelosas/complicaciones , Enfermedades Arteriales Intracraneales/complicaciones , Accidente Cerebrovascular/etiología , Adulto , Angiografía de Substracción Digital , Isquemia Encefálica/diagnóstico , Enfermedades Cerebelosas/diagnóstico , Femenino , Humanos , Enfermedades Arteriales Intracraneales/diagnóstico , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Factores de Riesgo , Hemorragia Subaracnoidea/complicaciones , Resultado del Tratamiento , Disección de la Arteria Vertebral/complicaciones
11.
Artículo en Inglés | MEDLINE | ID: mdl-24521416

RESUMEN

The main purpose of this study was to investigate the adsorption characteristics of cobalt, nickel and copper ions, which are harmful heavy metals released from various industries, in single, binary and ternary systems. The results showed that the adsorption extent decreased as the system changed from a single to a ternary system but adsorption percentages were not below 79%. The adsorption percentage of cobalt ion was superior to that of the other ions regardless of the type of system. In this study, the Langmuir isotherm was adapted for every adsorption result, and an extended version of the Langmuir isotherm was employed for the binary and ternary systems. The qmax value became smaller and KL value increased in the binary and ternary systems compared with that of the single system. The equilibrium parameter (RL) was between 0 and 1 under every condition, which indicated that adsorption was favorable. Finally, an adsorption experiment for real wastewater was performed, and the results were compared with those obtained for artificial wastewater.


Asunto(s)
Carbón Orgánico/química , Cobalto/química , Cobre/química , Níquel/química , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Adsorción , Cobalto/análisis , Cobre/análisis , Modelos Químicos , Níquel/análisis , Espectrofotometría Atómica
12.
Exp Mol Med ; 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39482531

RESUMEN

Human embryonic stem cells (hESCs) are naturally equipped to maintain genome integrity to minimize genetic mutations during early embryo development. However, genetic aberration risks and subsequent cellular changes in hESCs during in vitro culture pose a significant threat to stem cell therapy. While a few studies have reported specific somatic mutations and copy number variations (CNVs), the molecular mechanisms underlying the acquisition of 'culture-adapted phenotypes' by hESCs are largely unknown. Therefore, we conducted comprehensive genomic, single-cell transcriptomic, and single-cell ATAC-seq analyses of an isogenic hESC model displaying definitive 'culture-adapted phenotypes'. We found that hESCs lacking TP53, in which loss-of-function mutations were identified in human pluripotent stem cells (hPSCs), presented a surge in somatic mutations. Notably, hPSCs with a copy number gain of 20q11.21 during early passage did not present 'culture-adapted phenotypes' or BCL2L1 induction. Single-cell RNA-seq and ATAC-seq analyses revealed active transcriptional regulation at the 20q11.21 locus. Furthermore, the induction of BCL2L1 and TPX2 to trigger 'culture-adapted phenotypes' was associated with epigenetic changes facilitating TEA domain (TEAD) binding. These results suggest that 20q11.21 copy number gain and additional epigenetic changes are necessary for expressing 'culture-adapted phenotypes' by activating gene transcription at this specific locus.

13.
BMB Rep ; 55(12): 645-650, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36379512

RESUMEN

Epithelial-to-mesenchymal transition (EMT)-subtype gastric cancers have the worst prognosis due to their higher recurrence rate, higher probability of developing metastases and higher chemoresistance compared to those of other molecular subtypes. Pharmacologically actionable somatic mutations are rarely found in EMT-subtype gastric cancers, limiting the utility of targeted therapies. Here, we conducted a high-throughput chemical screen using 37 gastric cancer cell lines and 48,467 synthetic smallmolecule compounds. We identified YK-135, a small-molecule compound that showed higher cytotoxicity toward EMT-subtype gastric cancer cell lines than toward non-EMT-subtype gastric cancer cell lines. YK-135 exerts its cytotoxic effects by inhibiting mitochondrial complex I activity and inducing AMP-activated protein kinase (AMPK)-mediated apoptosis. We found that the lower glycolytic capacity of the EMT-subtype gastric cancer cells confers synthetic lethality to the inhibition of mitochondrial complex I, possibly by failing to maintain energy homeostasis. Other well-known mitochondrial complex I inhibitors (e.g., rotenone and phenformin) mimic the efficacy of YK-135, supporting our results. These findings highlight mitochondrial complex I inhibitors as promising therapeutic agents for EMT-subtype gastric cancers and YK-135 as a novel chemical scaffold for further drug development. [BMB Reports 2022; 55(12): 645-650].


Asunto(s)
Antineoplásicos , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Transición Epitelial-Mesenquimal
14.
Exp Mol Med ; 54(11): 1913-1926, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36357569

RESUMEN

Immune checkpoint therapies, such as programmed cell death ligand 1 (PD-L1) blockade, have shown remarkable clinical benefit in many cancers by restoring the function of exhausted T cells. Hence, the identification of novel PD-L1 regulators and the development of their inhibition strategies have significant therapeutic advantages. Here, we conducted pooled shRNA screening to identify regulators of membrane PD-L1 levels in lung cancer cells targeting druggable genes and cancer drivers. We identified WNK lysine deficient protein kinase 3 (WNK3) as a novel positive regulator of PD-L1 expression. The kinase-dead WNK3 mutant failed to elevate PD-L1 levels, indicating the involvement of its kinase domain in this function. WNK3 perturbation increased cancer cell death in cancer cell-immune cell coculture conditions and boosted the secretion of cytokines and cytolytic enzymes, promoting antitumor activities in CD4+ and CD8+ T cells. WNK463, a pan-WNK inhibitor, enhanced CD8+ T-cell-mediated antitumor activity and suppressed tumor growth as a monotherapy as well as in combination with a low-dose anti-PD-1 antibody in the MC38 syngeneic mouse model. Furthermore, we demonstrated that the c-JUN N-terminal kinase (JNK)/c-JUN pathway underlies WNK3-mediated transcriptional regulation of PD-L1. Our findings highlight that WNK3 inhibition might serve as a potential therapeutic strategy for cancer immunotherapy through its concurrent impact on cancer cells and immune cells.


Asunto(s)
Antígeno B7-H1 , Linfocitos T CD8-positivos , Neoplasias Pulmonares , Proteínas Serina-Treonina Quinasas , Animales , Ratones , Antígeno B7-H1/genética , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Inmunoterapia , Neoplasias Pulmonares/genética , Humanos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo
15.
Sci Rep ; 11(1): 17130, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34429501

RESUMEN

The role of matrix metalloproteinase-2 (MMP-2) in tumor cell migration has been widely studied, however, the characteristics and effects of MMP-2 in clinical sample of metastatic colorectal cancer (CRC) remain poorly understood. Here, in order to unveil the perturbed proteomic signal during MMP-2 induced cancer progression, we analyzed plasma proteome of CRC patients according to disease progression, HCT116 cancer secretome upon MMP-2 knockdown, and publicly available CRC tissue proteome data. Collectively, the integrative analysis of multi-layered proteomes revealed that a protein cluster containing EMT (Epithelial-to-Mesenchymal Transition)-associated proteins such as CD9-integrin as well as MMP-2. The proteins of the cluster were regulated by MMP-2 perturbation and exhibited significantly increased expressions in tissue and plasma as disease progressed from TNM (Tumor, Node, and Metastasis) stage I to II. Furthermore, we also identified a plausible association between MMP-2 up-regulation and activation of focal adhesion kinase signaling in the proteogenomic analysis of CRC patient tissues. Based on these comparative and integrative analyses, we suggest that the high invasiveness in the metastatic CRC resulted from increased secretion of MMP-2 and CD9-integrin complex mediated by FAK signaling activation.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Células Cultivadas , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Transición Epitelial-Mesenquimal , Quinasa 1 de Adhesión Focal/genética , Células HCT116 , Humanos , Metaloproteinasa 2 de la Matriz/genética , Metástasis de la Neoplasia , Proteoma/genética , Proteoma/metabolismo , Transducción de Señal , Tetraspanina 29/genética , Tetraspanina 29/metabolismo
16.
Hum Gene Ther ; 32(19-20): 1210-1223, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34498979

RESUMEN

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare disease caused by recessive mutations in the TYMP gene, which encodes the enzyme thymidine phosphorylase (TP). In this study, the efficient integration of a TYMP transgene into introns of the Tymp and Alb loci of hepatocytes in a murine model of MNGIE was achieved by the coordinated delivery and activity of CRISPR/Cas9 and a TYMP cDNA. CRISPR/Cas9 was delivered either as mRNA using lipid nanoparticle (LNP) or polymeric nanoparticle, respectively, or in an AAV2/8 viral vector; the latter was also used to package the TYMP cDNA. Insertion of the cDNA template downstream of the Tymp and Alb promoters ensured transgene expression. The best in vivo results were obtained using LNP carrying the CRISPR/Cas9 mRNAs. Treated mice showed a consistent long-term (1 year) reduction in plasma nucleoside (thymidine and deoxyuridine) levels that correlated with the presence of TYMP mRNA and functional enzyme in liver cells. In mice with an edited Alb locus, the transgene produced a hybrid Alb-hTP protein that was secreted, with supraphysiological levels of TP activity detected in the plasma. Equivalent results were obtained in mice edited at the Tymp locus. Finally, some degree of gene editing was found in animals treated only with AAV vectors containing the DNA templates, in the absence of nucleases, although there was no impact on plasma nucleoside levels. Overall, these results demonstrate the feasibility of liver-directed genome editing in the long-term correction of MNGIE, with several advantages over other methods.


Asunto(s)
Edición Génica , Encefalomiopatías Mitocondriales , Animales , Modelos Animales de Enfermedad , Liposomas , Ratones , Encefalomiopatías Mitocondriales/genética , Encefalomiopatías Mitocondriales/terapia , Nanopartículas , Timidina Fosforilasa
17.
Water Sci Technol ; 61(7): 1819-27, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20371941

RESUMEN

Oxygen has been so far addressed as the most preferable terminal electron acceptor in the cathodes of microbial fuel cells (MFCs). However, to reduce the oxygen reduction overpotential at the cathode surface, eco-unfriendly and costly catalysts have been commonly employed. Here, we pursued the possibility of using a high surface area electrode to reduce the cathodic reaction overpotential rather than the utilization of catalyzed materials. A dual chambered MFC reactor was designed with the use of graphite-granule electrodes and a permeable membrane. The performance of the reactor in terms of electricity generation and organic removal rate was examined under a continuous-feed manner. Results showed that the maximum volumetric power of 4.4+/-0.2 W/m(3) net anodic compartment (NAC) was obtained at a current density of 11+/-0.5 A/m(3) NAC. The power output was improved by increasing the electrolyte ionic strength. An acceptable effluent quality was attained when the organic loading rate (OLR) of 2 kgCOD/m(3) NAC d was applied. The organic removal rate seemed to be less affected by shock loading. Our system can be suggested as a promising approach to make MFC-based technology economically viable for wastewater treatment applications. This study shows that current generation can be remarkably improved in comparison with several other studies using a low-surface-area plain graphite electrode.


Asunto(s)
Fuentes de Energía Bioeléctrica , Conservación de los Recursos Naturales , Grafito/química , Eliminación de Residuos Líquidos , Reactores Biológicos , Electrodos , Membranas Artificiales
18.
Cancers (Basel) ; 12(6)2020 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-32486290

RESUMEN

Despite recent innovations and advances in early diagnosis, the prognosis of advanced gastric cancer remains poor due to a limited number of available therapeutics. Here, we employed pharmacogenomic analysis of 37 gastric cancer cell lines and 1345 small-molecule pharmacological compounds to investigate biomarkers predictive of cytotoxicity among gastric cancer cells to the tested drugs. We discovered that expression of CCNA2, encoding cyclin A2, was commonly associated with responses to polo-like kinase 1 (PLK1) inhibitors (BI-2536 and volasertib). We also found that elevated CCNA2 expression is required to confer sensitivity to PLK1 inhibitors through increased mitotic catastrophe and apoptosis. Further, we demonstrated that CCNA2 expression is elevated in KRAS mutant gastric cancer cell lines and primary tumors, resulting in an increased sensitivity to PLK1 inhibitors. Our study suggests that CCNA2 is a novel biomarker predictive of sensitivity to PLK1 inhibitors for the treatment of advanced gastric cancer, particularly cases carrying KRAS mutation.

19.
Nat Commun ; 11(1): 3288, 2020 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32620753

RESUMEN

The prognostic and therapeutic relevance of molecular subtypes for the most aggressive isocitrate dehydrogenase 1/2 (IDH) wild-type glioblastoma (GBM) is currently limited due to high molecular heterogeneity of the tumors that impedes patient stratification. Here, we describe a distinct binary classification of IDH wild-type GBM tumors derived from a quantitative proteomic analysis of 39 IDH wild-type GBMs as well as IDH mutant and low-grade glioma controls. Specifically, GBM proteomic cluster 1 (GPC1) tumors exhibit Warburg-like features, neural stem-cell markers, immune checkpoint ligands, and a poor prognostic biomarker, FKBP prolyl isomerase 9 (FKBP9). Meanwhile, GPC2 tumors show elevated oxidative phosphorylation-related proteins, differentiated oligodendrocyte and astrocyte markers, and a favorable prognostic biomarker, phosphoglycerate dehydrogenase (PHGDH). Integrating these proteomic features with the pharmacological profiles of matched patient-derived cells (PDCs) reveals that the mTORC1/2 dual inhibitor AZD2014 is cytotoxic to the poor prognostic PDCs. Our analyses will guide GBM prognosis and precision treatment strategies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Isocitrato Deshidrogenasa/genética , Proteogenómica/métodos , Proteómica/métodos , Benzamidas/farmacología , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Isocitrato Deshidrogenasa/clasificación , Isocitrato Deshidrogenasa/metabolismo , Estimación de Kaplan-Meier , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Morfolinas/farmacología , Mutación , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología
20.
Water Sci Technol ; 59(9): 1803-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19448316

RESUMEN

Simultaneous organics removal and nitrification using a novel nitrifying biocathode microbial fuel cell (MFC) reactor were investigated in this study. Remarkably, the introduction of nitrifying biomass into the cathode chamber caused higher voltage outputs than that of MFC operated with the abiotic cathode. Results showed the maximum power density increased 18% when cathode was run under the biotic condition and fed by nitrifying medium with alkalinity/NH4+-N ratio of 8 (26 against 22 mW/m2). The voltage output was not differentiated when NH4+-N concentration was increased from 50 to 100 mg/L under such alkalinity/NH4+-N ratio. However, interestingly, the cell voltage rose significantly when the alkalinity/NH4+-N ratio was decreased to 6. Consequently, the maximum power density increased 68% in compared with the abiotic cathode MFC (37 against 22 mW/m2). Polarization curves demonstrated that both activation and concentration losses were lowered during the period of nitrifying biocathode operation. Ammonium was totally nitrified and mostly converted to nitrate in all cases of the biotic cathode conditions. High COD removal efficiency (98%) was achieved. In light of the results presented here, the application of nitrifying biocathode is not only able to integrate the nitrogen and carbon removal but also to enhance the power generation in MFC system. Our system can be suggested to open up a new feasible way for upgrading and retrofitting the existing wastewater treatment plant by the use of MFC-based technologies.


Asunto(s)
Fuentes de Energía Bioeléctrica/microbiología , Reactores Biológicos , Purificación del Agua/instrumentación , Bacterias/metabolismo , Conservación de los Recursos Energéticos/métodos , Nitritos/metabolismo , Purificación del Agua/métodos
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