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1.
Hepatology ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557414

RESUMEN

BACKGROUND AND AIMS: Epigenetic reprogramming and escape from terminal differentiation are poorly understood enabling characteristics of liver cancer. Keratin 19 (KRT19), classically known to form the intermediate filament cytoskeleton, is a marker of stemness and worse prognosis in liver cancer. This study aimed to address the functional roles of KRT19 in liver tumorigenesis and to elucidate the underlying mechanisms. APPROACH AND RESULTS: Using multiplexed genome editing of hepatocytes in vivo, we demonstrated that KRT19 promoted liver tumorigenesis in mice. Cell fractionation revealed a previously unrecognized nuclear fraction of KRT19. Tandem affinity purification identified histone deacetylase 1 and REST corepressor 1, components of the corepressor of RE-1 silencing transcription factor (CoREST) complex as KRT19-interacting proteins. KRT19 knockout markedly enhanced histone acetylation levels. Mechanistically, KRT19 promotes CoREST complex formation by enhancing histone deacetylase 1 and REST corepressor 1 interaction, thus increasing the deacetylase activity. ChIP-seq revealed hepatocyte-specific genes, such as hepatocyte nuclear factor 4 alpha ( HNF4A ), as direct targets of KRT19-CoREST. In addition, we identified forkhead box P4 as a direct activator of aberrant KRT19 expression in liver cancer. Furthermore, treatment of primary liver tumors and patient-derived xenografts in mice suggest that KRT19 expression has the potential to predict response to histone deacetylase 1 inhibitors especially in combination with lenvatinib. CONCLUSIONS: Our data show that nuclear KRT19 acts as a transcriptional corepressor through promoting the deacetylase activity of the CoREST complex, resulting in dedifferentiation of liver cancer. These findings reveal a previously unrecognized function of KRT19 in directly shaping the epigenetic landscape in cancer.

3.
Int J Clin Pract ; 2023: 6644168, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37901849

RESUMEN

Background: Tumor progression and the therapeutic resistance associated with cancer agents are thought to be modulated by circular RNAs (circRNAs); however, its mechanism associated with nonsmall cell lung cancer (NSCLC) is still undetermined. The following investigation aimed to evaluate the involvement of circRNAs with NSCLC. Methods: The serum specimens of 146 NSCLC individuals who received complete four cycles of PTX chemotherapy were collected. The serum concentration of hsa_circ_0005962 of these individuals was assessed with quantitative real-time polymerase chain reaction (qRT-PCR), followed by the evaluation of demographic and survival consequences for further assessments. Results: It was revealed that hsa_circ_0005962 is substantially increased in NSCLC chemoresistant patients and was positively correlated with the disease stage. Furthermore, the hsa_circ_0005962 value of the area under the curve was moderate, and increased hsa_circ_0005962 expression was linked with shorter overall survival (OS). Hsa_circ_0005962 stimulated paclitaxel resistance (PTX-R) in resistant NSCLC cells by regulating the axis of miR-126-5p/insulin-like growth factor 1 (IGF1). Conclusion: The results of this investigation highlight that hsa_circ_0005962 induces chemoresistance in NSCLC patients and, therefore, can act as a physiological target to treat NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , ARN Circular/genética , ARN Circular/metabolismo , Paclitaxel/uso terapéutico , Pronóstico , Biomarcadores
4.
Pharmgenomics Pers Med ; 16: 805-815, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37692338

RESUMEN

Background: Circular RNAs (circRNAs) demonstrated critical roles within developing tumors and treatment resistance in an increasing body of research. The aim was to look into the functions and processes of hsa_circ_0003489 in the non-small cell lung cancer (NSCLC) paclitaxel (PTX) resistance. Methods: NSCLC cell-based cultures including A549 and H460 were employed for such an investigation. hsa_circ_0003489, miR-98-5p, and insulin-like growth factor 2 (IGF2) expression-profiles were evaluated with a quantitative real-time polymerase chain reaction (RT-qPCR). The PTX resistance was determined using MTT assay, and the ELISA test measured IGF2 expression. Facilitating corroboration for miR-98-5p relation and hsa_circ_0003489 or IGF2, a dual-luciferase reporter method was applied. Results: The hsa_circ_0003489 level was raised in cells and tissues from PTX-resistant (PR) NSCLC. In PR NSCLC cells, hsa_circ_0003489 knockdown reduced PTX resistance. For the purpose of the mechanism study, hsa_circ_0003489 knockdown substantially reduced IGF2 expression via miR-98-5p sponging, improving PTX sensitivity in PR NSCLC. Conclusion: Through miR-98-5p/IGF2 axis control, hsa_circ_0003489 knockdown helped NSCLC overcome PTX resistance, suggesting a potential circRNA-targeted therapy for the disease.

5.
IEEE Trans Cybern ; PP2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37535489

RESUMEN

High-precision and safety control in face of disturbances and uncertainties is a challenging issue of both theoretical and practical importance. In this article, new adaptive anti-disturbance control schemes are proposed for a class of uncertain nonlinear systems with composite disturbances, including additive disturbances, multiplicative actuator faults, and implicit disturbances deeply coupled with system states. Both the cases with known and unknown control/fault directions are investigated. By properly fusing the techniques of disturbance observers and adaptive compensation, it is shown that all closed-loop signals are globally uniformly bounded and the tracking error converges to zero asymptotically, no matter the control/fault directions are known or not. In the case of known directions, the proposed control scheme, for the first time, guarantees asymptotic tracking and L ∞ tracking performance simultaneously in face of disturbances and actuator faults. Moreover, novel Nussbaum functions and a contradiction argument are introduced, which allow the system to have multiple unknown nonidentical control directions and unknown time-varying fault direction. Simulation results illustrate the effectiveness of the proposed control schemes.

6.
Int J Genomics ; 2023: 8845152, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37361693

RESUMEN

Circular RNAs (circRNAs) have been shown to have critical roles in developing cancer and treatment resistance in an increasing body of research. The aim was to look into the functions and processes of hsa_circ_0003220 in the non-small cell lung cancer (NSCLC) chemoresistance. The NSCLC cell lines H460 and A549 were employed in present work. hsa_circ_0003220, miR-489-3p, and insulin-like growth factors (IGF1) mRNA levels were assessed with a quantitative real time polymerase chain reaction (qRT-PCR). The cisplatin, docetaxel, and paclitaxel (PTX) resistances were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the enzyme linked immunosorbent assay (ELISA) test measured IGF1 expression. In order to corroborate the miR-489-3p relation with hsa_circ_0003220 or IGF1, a dual-luciferase reporter method was applied. The level of hsa_circ_0003220 was raised in cells and tissues from PTX-resistant (PR) NSCLC. In PR NSCLC cells, hsa_circ_0003220 knockdown reduced chemoresistance. For the purpose of the mechanism study, hsa_circ_0003220 knockdown substantially reduced IGF1 expression via miR-489-3p sponging, reducing chemoresistance in PR NSCLC cells. By controlling the miR-489-3p/IGF1 axis, hsa_circ_0003220 knockdown helped NSCLC overcome chemoresistance, suggesting a potential circRNA-targeted therapy for the disease.

7.
JID Innov ; 3(2): 100174, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36699196

RESUMEN

CARD14-associated papulosquamous eruption is an autosomal dominant genodermatosis characterized by early-onset, generalized erythematous patches and plaques with prominent scales, mostly with facial involvement. Heterozygous gain-of-function variants in the CARD14 gene have been reported to be causative for this entity. The pathogenesis mainly involves the IL-23‒IL-17 inflammatory circuit, yet the efficacy of anti‒IL-17 treatment remained less examined. In this study, we report one previously unidentified variant underlying the CARD14-associated papulosquamous eruption and showed its gain-of-function property. Furthermore, we present the beneficial effect of anti‒IL-17A treatment in our patient.

8.
Eur Arch Otorhinolaryngol ; 280(2): 839-845, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36066668

RESUMEN

OBJECTIVES: The aim of this study was to investigate the relationship between matrix metalloproteinase-7 (MMP-7) expression and the clinical and pathological characteristics of salivary adenoid cystic carcinomas (SACC) of the palatal minor salivary gland. METHODS: In this study, 58 samples of SACC and 10 samples of normal salivary gland tissue were examined. Immunohistochemistry was used to detect MMP-7 and vascular endothelial growth factor A (VEGF-A) expression in SACC and normal tissues. The clinical and pathological characteristics of the patients with SACC were collected. RESULTS: Of the 58 SACC samples, 44 were positive for MMP-7, and the expression rate was 75.9%. No expression was detected in the 10 normal salivary gland tissues. The level of MMP-7 expression in the SACC and normal samples was significantly different. The level of expression of MMP-7 in the SACC samples did not correlate with age, sex or pathological type but did correlate with pathological grade, nerve infiltration and clinical stage. There was a positive correlation between VEGF-A and MMP-7 expression. CONCLUSIONS: The SACC samples showed high expression of MMP-7, which was associated with tumour differentiation, invasiveness and clinical stage. The detection of MMP-7 positively correlated with the detection of VEGF-A in SACC.


Asunto(s)
Carcinoma Adenoide Quístico , Metaloproteinasa 7 de la Matriz , Neoplasias de las Glándulas Salivales , Humanos , Carcinoma Adenoide Quístico/patología , Línea Celular Tumoral , Metaloproteinasa 7 de la Matriz/metabolismo , Neoplasias de las Glándulas Salivales/patología , Glándulas Salivales Menores/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
Eur Arch Otorhinolaryngol ; 279(12): 5869-5875, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35781742

RESUMEN

OBJECTIVE: To explore the VEGF-A expression in salivary gland adenoid cystic carcinoma tissues and detect the relationship between the mechanism of occurrence, development and metastasis of jaws with salivary gland adenoid cystic carcinoma and VEGF-A expression. METHODS: Paraffin samples from 58 cases of SACC of the palate and ten cases of normal salivary gland tissues were collected. The expression levels of VEGF-A protein were detected using the immunohistochemistry EnVision system. RESULTS: Among the 58 cases, there were 20 cases of the cribriform type, 17 cases of the tubular type, and 21 cases of the solid type. There were 9 cases with lymph node metastasis and 21 cases without lymph node metastasis. And there were 8 cases of T1, 15 cases of T2, and 7 cases of T3/T4. The positive expression rate of VEGF-A in SACC of the palate was 74.1%, which was higher than that found in normal salivary gland tissues (10%). The VEGF-A was localized in the cytoplasm/cell membrane. CONCLUSION: VEGF-A is highly expressed in SACC of the palate. The level of expression is closely related to the pathological grade, lymph node metastasis, and clinical stage of the tumor, and it can thus be used as an important indicator for judging the biological behavior of SACC of the palate.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias de las Glándulas Salivales , Factor A de Crecimiento Endotelial Vascular , Humanos , Carcinoma Adenoide Quístico/patología , Metástasis Linfática/patología , Hueso Paladar/patología , Neoplasias de las Glándulas Salivales/patología , Glándulas Salivales/patología , Factor A de Crecimiento Endotelial Vascular/genética
10.
Sci Adv ; 8(28): eabn5295, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35857506

RESUMEN

27-Hydroxycholesterol (27-HC) is the most abundant oxysterol that increases the risk of breast cancer progression. However, little is known about epigenetic regulation of 27-HC metabolism and its role in breast tumor initiation. Using genetic mouse mammary tumor and human breast cancer models, we showed here that the histone reader ZMYND8 was selectively expressed in breast cancer stem cells (BCSCs) and promoted epithelial-mesenchymal transition (EMT), BCSC maintenance and self-renewal, and oncogenic transformation through its epigenetic functions, leading to breast tumor initiation. Mechanistically, ZMYND8 was a master transcriptional regulator of 27-HC metabolism. It increased cholesterol biosynthesis and oxidation but blocked cholesterol efflux and 27-HC catabolism, leading to accumulation of 27-HC in BCSCs. Consequently, 27-HC promoted EMT, oncogenic transformation, and tumor initiation through activation of liver X receptor. These findings reveal that ZMYND8 is an epigenetic booster that drives breast tumor initiation through metabolic reprogramming.


Asunto(s)
Neoplasias de la Mama , Animales , Neoplasias de la Mama/patología , Carcinogénesis/patología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Colesterol/metabolismo , Epigénesis Genética , Femenino , Humanos , Hidroxicolesteroles , Ratones , Células Madre Neoplásicas/metabolismo
11.
Nucleic Acids Res ; 50(11): 6313-6331, 2022 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-35648484

RESUMEN

Poly(ADP-ribose) polymerase-1 (PARP-1) is a DNA damage sensor and contributes to both DNA repair and cell death processes. However, how PARP-1 signaling is regulated to switch its function from DNA repair to cell death remains largely unknown. Here, we found that PARP-1 plays a central role in alkylating agent-induced PARthanatic cancer cell death. Lysine demethylase 6B (KDM6B) was identified as a key regulator of PARthanatos. Loss of KDM6B protein or its demethylase activity conferred cancer cell resistance to PARthanatic cell death in response to alkylating agents. Mechanistically, KDM6B knockout suppressed methylation at the promoter of O6-methylguanine-DNA methyltransferase (MGMT) to enhance MGMT expression and its direct DNA repair function, thereby inhibiting DNA damage-evoked PARP-1 hyperactivation and subsequent cell death. Moreover, KDM6B knockout triggered sustained Chk1 phosphorylation and activated a second XRCC1-dependent repair machinery to fix DNA damage evading from MGMT repair. Inhibition of MGMT or checkpoint response re-sensitized KDM6B deficient cells to PARthanatos induced by alkylating agents. These findings provide new molecular insights into epigenetic regulation of PARP-1 signaling mediating DNA repair or cell death and identify KDM6B as a biomarker for prediction of cancer cell vulnerability to alkylating agent treatment.


Asunto(s)
Dacarbazina , Parthanatos , Alquilantes , ADN , Reparación del ADN , Dacarbazina/farmacología , Epigénesis Genética , Guanina/análogos & derivados , O(6)-Metilguanina-ADN Metiltransferasa/genética , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Temozolomida/farmacología
12.
Sci Adv ; 8(25): eabn5683, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35731873

RESUMEN

Mechanistic study and precision treatment of primary liver cancer (PLC) are hindered by marked heterogeneity, which is challenging to recapitulate in any given liver cancer mouse model. Here, we report the generation of 25 mouse models of PLC by in situ genome editing of hepatocytes recapitulating 25 single or combinations of human cancer driver genes. These mouse tumors represent major histopathological types of human PLCs and could be divided into three human-matched molecular subtypes based on transcriptomic and proteomic profiles. Phenotypical characterization identified subtype- or genotype-specific alterations in immune microenvironment, metabolic reprogramming, cell proliferation, and expression of drug targets. Furthermore, single-cell analysis and expression tracing revealed spatial and temporal dynamics in expression of pyruvate kinase M2 (Pkm2). Tumor-specific knockdown of Pkm2 by multiplexed genome editing reversed the Warburg effect and suppressed tumorigenesis in a genotype-specific manner. Our study provides mouse PLC models with defined genetic drivers and characterized phenotypical heterogeneity suitable for mechanistic investigation and preclinical testing.

13.
Cancer Res ; 82(13): 2388-2402, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35499760

RESUMEN

Branched-chain amino acid transaminase 1 (BCAT1) is upregulated selectively in human isocitrate dehydrogenase (IDH) wildtype (WT) but not mutant glioblastoma multiforme (GBM) and promotes IDHWT GBM growth. Through a metabolic synthetic lethal screen, we report here that α-ketoglutarate (AKG) kills IDHWT GBM cells when BCAT1 protein is lost, which is reversed by reexpression of BCAT1 or supplementation with branched-chain α-ketoacids (BCKA), downstream metabolic products of BCAT1. In patient-derived IDHWT GBM tumors in vitro and in vivo, cotreatment of BCAT1 inhibitor gabapentin and AKG resulted in synthetic lethality. However, AKG failed to evoke a synthetic lethal effect with loss of BCAT2, BCKDHA, or GPT2 in IDHWT GBM cells. Mechanistically, loss of BCAT1 increased the NAD+/NADH ratio but impaired oxidative phosphorylation, mTORC1 activity, and nucleotide biosynthesis. These metabolic alterations were synergistically augmented by AKG treatment, thereby causing mitochondrial dysfunction and depletion of cellular building blocks, including ATP, nucleotides, and proteins. Partial restoration of ATP, nucleotides, proteins, and mTORC1 activity by BCKA supplementation prevented IDHWT GBM cell death conferred by the combination of BCAT1 loss and AKG. These findings define a targetable metabolic vulnerability in the most common subset of GBM that is currently incurable. SIGNIFICANCE: Metabolic synthetic lethal screening in IDHWT glioblastoma defines a vulnerability to ΑΚG following BCAT1 loss, uncovering a therapeutic strategy to improve glioblastoma treatment. See related commentary by Meurs and Nagrath, p. 2354.


Asunto(s)
Glioblastoma , Adenosina Trifosfato , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Ácidos Cetoglutáricos/farmacología , Diana Mecanicista del Complejo 1 de la Rapamicina , Nucleótidos , Mutaciones Letales Sintéticas , Transaminasas/genética , Transaminasas/metabolismo
14.
Biomass Convers Biorefin ; : 1-17, 2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35342681

RESUMEN

In this study, the second-order model, Fick's second law of diffusion, and the Peleg model were used to evaluate the extraction kinetic model of polysaccharide (CPP) from Codonopsis pilosula. The characteristic functional groups, surface structure, and physical and chemical properties of CPP were analyzed by multi-spectroscopic and microscopic techniques. The results showed that the extraction process agreed well with the second-order model, Fick's second diffusion law, and Peleg model. Rheological tests showed that CPP exhibited different viscosity changes under different conditions (Solution viscosity was inversely proportional to temperature, time, etc.; proportional to polysaccharide concentration, Na+ content, etc.). CPP was composed of molecular aggregates composed of small particles, with more pore structure and basically completely decomposed at 130 °C. The hypoglycemic study showed that CPP had a strong inhibitory effect on α-glycosidase than α-amylase. The morphology and subsequent structural features, anti-diabetic potential, and rheological properties of CPP were revealed to provide a theoretical basis for the development of pharmaceutical preparations or health food and functional food for the treatment of diabetes. Supplementary Information: The online version contains supplementary material available at 10.1007/s13399-022-02518-w.

15.
J Biomater Appl ; 36(10): 1723-1736, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35235468

RESUMEN

In this study, after optimizing the extraction process of CPP (Codonopsis pilosula polysaccharides), CPPM (CPP microcapsules) were prepared. Subsequently, the structural characteristics and physicochemical properties were studied. The results showed that CPPM is a hollow sac-like structure with rough folds and protuberances and comes in spherical or ellipsoidal shapes with uniform particle size. CPPM has certain swelling degree, low hardness, good adhesion, and stability. Then, the effect of CPPM on wounds repair was investigated by a rat model. The results showed that CPPM could improve the wound healing rate. Histological evaluation showed CPPM could promote neovascularization and fibroblast proliferation. By investigating the healing mechanism, it was found that CPPM increased the hydroxyproline content in granulation tissue and had an excellent antioxidant ability, and then inhibited lipid peroxidation, in addition, it significantly increased the transcript levels of VEGF and miRNA-21 genes, indicating that CPPM play an influential role in vascular remodeling during wound healing by up-regulating the expression of VEGF and miRNA-21 genes.


Asunto(s)
Codonopsis , Animales , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Cápsulas/química , Codonopsis/química , Polisacáridos/química , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Ratas , Cicatrización de Heridas
16.
Biomed Mater ; 17(2)2022 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-35090145

RESUMEN

The crude polysaccharide (CPNP) ofCodonopsis pilosulawas obtained by hot-water extraction technology. The extraction kinetic model established according to Fick's first law of diffusion and related parameters of polysaccharide was studied. CPNP microcapsules were prepared by blending with sodium alginate, Ca2+ions and crude CPNP. The quality control (drug loading rate, embedding rate and release rate, etc) of CPNP microcapsules were analyzed by pharmacopeas standards. The structure feature of CPNP microcapsules also were determined with various methods. The wound healing ability of CPNP microcapsules loading with different concentration of CPNP was evaluated using the rat wound model. The activity of various enzymes and the expression levels of pro-inflammatory factors in the model skin tissue also were determined by enzyme linked immunosorbent assay (ELISA). Hematoxylin-eosin staining (HE), Masson, immunohistochemistry were used to investigate the external application effect of CPNP microcapsules on skin wound repair. The extraction kinetics of CPNP was established with the linear correlation coefficient (R2) of 0.83-0.93, implied that the extraction process was fitted well with the Fick's first law of diffusion. The CPNP has good compatibility with sodium alginate and Ca2+ions by SEM and TEM observation, and the particle size of CPNP microcapsules was 21.25 ± 2.84 µm with the good degradation rate, loading rate (61.59%) and encapsulation rate (55.99%), maximum swelling rate (397.380 ± 25.321%). Compared with control group, the redness, and swelling, bleeding, infection, and exudate of the damaged skin decreased significantly after CPNP microcapsules treatment, and the CPNP microcapsules groups exhibited good wound healing function with less inflammatory cell infiltration. The pathological structure showed that in the CPNP microcapsules group, more newborn capillaries, complete skin structure, and relatively tight and orderly arrangement of collagen fibers were observed in the skin of rats. CPNP microcapsules could effectively inhibit the high expression of pro-inflammatory factors in damaged skin, and significantly increase the contents of related enzymes (GSH-Px, T-AOC, LPO) and collagen fibers. The relative expression levels of genes (VEGF and miRNA21) in the CPNP microcapsules group were higher than those in the model group and the negative group. The above results suggested that the CPNP microcapsules could controlled-release the CPNP to the wound surface, and then played a better role in antibacterial, anti-inflammatory and skin wound repair.


Asunto(s)
MicroARNs , Cicatrización de Heridas , Animales , Cápsulas , Cinética , Polisacáridos , Ratas , Piel
17.
IEEE Trans Cybern ; 52(5): 3057-3068, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33027019

RESUMEN

In this article, under directed graphs, an adaptive consensus tracking control scheme is proposed for a class of nonlinear multiagent systems with completely unknown control coefficients. Unlike the existing results, here, each agent is allowed to have multiple unknown nonidentical control directions, and continuous communication between neighboring agents is not needed. For each agent, we design a group of novel Nussbaum functions and construct a monotonously increasing sequence in which the effects of our Nussbaum functions reinforce rather than counteract each other. With these efforts, the obstacle caused by the unknown control directions is successfully circumvented. Moreover, an event-triggering mechanism is introduced to determine the time instants for communication, which considerably reduces the communication burden. It is shown that all closed-loop signals are globally uniformly bounded and the tracking errors can converge to an arbitrarily small residual set. Simulation results illustrate the effectiveness of the proposed scheme.

18.
IEEE Trans Neural Netw Learn Syst ; 33(12): 7644-7654, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34138721

RESUMEN

In this article, a novel composite hierarchical antidisturbance control (CHADC) algorithm aided by the information-theoretic learning (ITL) technique is developed for non-Gaussian stochastic systems subject to dynamic disturbances. The whole control process consists of some time-domain intervals called batches. Within each batch, a CHADC scheme is applied to the system, where a disturbance observer (DO) is employed to estimate the dynamic disturbance and a composite control strategy integrating feedforward compensation and feedback control is adopted. The information-theoretic measure (entropy or information potential) is employed to quantify the randomness of the controlled system, based on which the gain matrices of DO and feedback controller are updated between two adjacent batches. In this way, the mean-square stability is guaranteed within each batch, and the system performance is improved along with the progress of batches. The proposed algorithm has enhanced disturbance rejection ability and good applicability to non-Gaussian noise environment, which contributes to extending CHADC theory to the general stochastic case. Finally, simulation examples are included to verify the effectiveness of theoretical results.

19.
Nat Commun ; 12(1): 2954, 2021 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-34012010

RESUMEN

How cancer cells cope with high levels of replication stress during rapid proliferation is currently unclear. Here, we show that macrophage migration inhibitory factor (MIF) is a 3' flap nuclease that translocates to the nucleus in S phase. Poly(ADP-ribose) polymerase 1 co-localizes with MIF to the DNA replication fork, where MIF nuclease activity is required to resolve replication stress and facilitates tumor growth. MIF loss in cancer cells leads to mutation frequency increases, cell cycle delays and DNA synthesis and cell growth inhibition, which can be rescued by restoring MIF, but not nuclease-deficient MIF mutant. MIF is significantly upregulated in breast tumors and correlates with poor overall survival in patients. We propose that MIF is a unique 3' nuclease, excises flaps at the immediate 3' end during DNA synthesis and favors cancer cells evading replication stress-induced threat for their growth.


Asunto(s)
Neoplasias de la Mama/metabolismo , Replicación del ADN/fisiología , Endonucleasas de ADN Solapado/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , ADN/química , ADN/metabolismo , Daño del ADN , ADN Polimerasa III/genética , ADN Polimerasa III/metabolismo , Replicación del ADN/genética , Femenino , Endonucleasas de ADN Solapado/deficiencia , Endonucleasas de ADN Solapado/genética , Técnicas de Inactivación de Genes , Inestabilidad Genómica , Células HCT116 , Humanos , Oxidorreductasas Intramoleculares/deficiencia , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/deficiencia , Factores Inhibidores de la Migración de Macrófagos/genética , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Conformación de Ácido Nucleico , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Fase S , Especificidad por Sustrato
20.
Elife ; 102021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33988507

RESUMEN

The human kinome comprises 538 kinases playing essential functions by catalyzing protein phosphorylation. Annotation of subcellular distribution of the kinome greatly facilitates investigation of normal and disease mechanisms. Here, we present Kinome Atlas (KA), an image-based map of the kinome annotated to 10 cellular compartments. 456 epitope-tagged kinases, representing 85% of the human kinome, were expressed in HeLa cells and imaged by immunofluorescent microscopy under a similar condition. KA revealed kinase family-enriched subcellular localizations and discovered a collection of new kinase localizations at mitochondria, plasma membrane, extracellular space, and other structures. Furthermore, KA demonstrated the role of liquid-liquid phase separation in formation of kinase condensates. Identification of MOK as a mitochondrial kinase revealed its function in cristae dynamics, respiration, and oxidative stress response. Although limited by possible mislocalization due to overexpression or epitope tagging, this subcellular map of the kinome can be used to refine regulatory mechanisms involving protein phosphorylation.


Asunto(s)
Mitocondrias/enzimología , Proteínas Quinasas , Fracciones Subcelulares/enzimología , Epítopos , Células HeLa , Humanos , Microscopía Fluorescente , Orgánulos , Fosforilación
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