Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Sci Total Environ ; 946: 174246, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38955266

RESUMEN

The ionizing radiation (IR) represents a formidable challenge as an environmental factor to mitochondria, leading to disrupt cellular energy metabolism and posing health risks. Although the deleterious impacts of IR on mitochondrial function are recognized, the specific molecular targets remain incompletely elucidated. In this study, HeLa cells subjected to γ-rays exhibited concomitant oxidative stress, mitochondrial structural alterations, and diminished ATP production capacity. The γ-rays induced a dose-dependent induction of mitochondrial fission, simultaneously manifested by an elevated S616/S637 phosphorylation ratio of the dynamin-related protein 1 (DRP1) and a reduction in the expression of the mitochondrial fusion protein mitofusin 2 (MFN2). Knockdown of DRP1 effectively mitigated γ-rays-induced mitochondrial network damage, implying that DRP1 phosphorylation may act as an effector of radiation-induced mitochondrial damage. The mitochondrial outer membrane protein voltage-dependent anion channel 1 (VDAC1) was identified as a crucial player in IR-induced mitochondrial damage. The VDAC1 inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), counteracts the excessive mitochondrial fission induced by γ-rays, consequently rebalancing the glycolytic and oxidative phosphorylation equilibrium. This metabolic shift was uncovered to enhance glycolytic capacity, thus fortifying cellular resilience and elevating the radiosensitivity of cancer cells. These findings elucidate the intricate regulatory mechanisms governing mitochondrial morphology under radiation response. It is anticipated that the development of targeted drugs directed against VDAC1 may hold promise in augmenting the sensitivity of tumor cells to radiotherapy and chemotherapy.

2.
Cell Death Dis ; 15(3): 209, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480704

RESUMEN

Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring radiation resistance to tumor cells. How radiation changes the glycolysis status of cancer cells is still unclear. Here we revealed the role of TAB182 in regulating glycolysis and lactate production in cellular response to ionizing radiation. Irradiation can significantly stimulate the production of TAB182 protein, and inhibiting TAB182 increases cellular radiosensitivity. Proteomic analysis indicated that TAB182 influences several vital biological processes, including multiple metabolic pathways. Knockdown of TAB182 results in decreased lactate production and increased pyruvate and ATP levels in cancer cells. Moreover, knocking down TAB182 reverses radiation-induced metabolic changes, such as radioresistant-related lactate production. TAB182 is necessary for activating LDHA transcription by affecting transcription factors SP1 and c-MYC; its knockdown attenuates the upregulation of LDHA by radiation, subsequently suppressing lactate production. Targeted suppression of TAB182 significantly enhances the sensitivity of murine xenograft tumors to radiotherapy. These findings advance our understanding of glycolytic metabolism regulation in response to ionizing radiation, which may offer significant implications for developing new strategies to overcome tumor radioresistance.


Asunto(s)
L-Lactato Deshidrogenasa , Proteómica , Humanos , Animales , Ratones , L-Lactato Deshidrogenasa/metabolismo , Lactato Deshidrogenasa 5/metabolismo , Línea Celular Tumoral , Glucólisis , Lactatos , Tolerancia a Radiación/genética
3.
Mol Ther ; 31(9): 2633-2650, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37482682

RESUMEN

Chromatin remodeling and N6-methyladenosine (m6A) modification are two critical layers in controlling gene expression and DNA damage signaling in most eukaryotic bioprocesses. Here, we report that poly(ADP-ribose) polymerase 1 (PARP1) controls the chromatin accessibility of METTL3 to regulate its transcription and subsequent m6A methylation of poly(A)+ RNA in response to DNA damage induced by radiation. The transcription factors nuclear factor I-C (NFIC) and TATA binding protein (TBP) are dependent on PARP1 to access the METTL3 promoter to activate METTL3 transcription. Upon irradiation or PARP1 inhibitor treatment, PARP1 disassociated from METTL3 promoter chromatin, which resulted in attenuated accessibility of NFIC and TBP and, consequently, suppressed METTL3 expression and RNA m6A methylation. Lysophosphatidic Acid Receptor 5 (LPAR5) mRNA was identified as a target of METTL3, and m6A methylation was located at A1881. The level of m6A methylation of LPAR5 significantly decreased, along with METTL3 depression, in cells after irradiation or PARP1 inhibition. Mutation of the LPAR5 A1881 locus in its 3' UTR results in loss of m6A methylation and, consequently, decreased stability of LPAR5 mRNA. METTL3-targeted small-molecule inhibitors depress murine xenograft tumor growth and exhibit a synergistic effect with radiotherapy in vivo. These findings advance our comprehensive understanding of PARP-related biological roles, which may have implications for developing valuable therapeutic strategies for PARP1 inhibitors in oncology.


Asunto(s)
Cromatina , Neoplasias , Humanos , Ratones , Animales , Cromatina/genética , Metilación , ARN/metabolismo , Factores de Transcripción/genética , ARN Mensajero/genética , Neoplasias/genética , Neoplasias/radioterapia , Metiltransferasas/genética , Metiltransferasas/metabolismo , Poli(ADP-Ribosa) Polimerasa-1/genética , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Receptores del Ácido Lisofosfatídico/genética , Receptores del Ácido Lisofosfatídico/metabolismo
4.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37108815

RESUMEN

DNA damage in astronauts induced by cosmic radiation poses a major barrier to human space exploration. Cellular responses and repair of the most lethal DNA double-strand breaks (DSBs) are crucial for genomic integrity and cell survival. Post-translational modifications (PTMs), including phosphorylation, ubiquitylation, and SUMOylation, are among the regulatory factors modulating a delicate balance and choice between predominant DSB repair pathways, such as non-homologous end joining (NHEJ) and homologous recombination (HR). In this review, we focused on the engagement of proteins in the DNA damage response (DDR) modulated by phosphorylation and ubiquitylation, including ATM, DNA-PKcs, CtIP, MDM2, and ubiquitin ligases. The involvement and function of acetylation, methylation, PARylation, and their essential proteins were also investigated, providing a repository of candidate targets for DDR regulators. However, there is a lack of radioprotectors in spite of their consideration in the discovery of radiosensitizers. We proposed new perspectives for the research and development of future agents against space radiation by the systematic integration and utilization of evolutionary strategies, including multi-omics analyses, rational computing methods, drug repositioning, and combinations of drugs and targets, which may facilitate the use of radioprotectors in practical applications in human space exploration to combat fatal radiation hazards.


Asunto(s)
Daño del ADN , Procesamiento Proteico-Postraduccional , Humanos , Fosforilación , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , ADN , Reparación del ADN
5.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36835431

RESUMEN

Mitochondrion is an important organelle of eukaryotic cells and a critical target of ionizing radiation (IR) outside the nucleus. The biological significance and mechanism of the non-target effect originating from mitochondria have received much attention in the field of radiation biology and protection. In this study, we investigated the effect, role, and radioprotective significance of cytosolic mitochondrial DNA (mtDNA) and its associated cGAS signaling on hematopoietic injury induced by IR in vitro culture cells and in vivo total body irradiated mice in this study. The results demonstrated that γ-ray exposure increases the release of mtDNA into the cytosol to activate cGAS signaling pathway, and the voltage-dependent anion channel (VDAC) may contribute to IR-induced mtDNA release. VDAC1 inhibitor DIDS and cGAS synthetase inhibitor can alleviate bone marrow injury and ameliorate hematopoietic suppression induced by IR via protecting hematopoietic stem cells and adjusting subtype distribution of bone marrow cells, such as attenuating the increase of the F4/80+ macrophage proportion in bone marrow cells. The present study provides a new mechanistic explanation for the radiation non-target effect and an alternative technical strategy for the prevention and treatment of hematopoietic acute radiation syndrome.


Asunto(s)
Citosol , ADN Mitocondrial , Hematopoyesis , Mitocondrias , Nucleotidiltransferasas , Traumatismos Experimentales por Radiación , Animales , Ratones , Citosol/metabolismo , ADN Mitocondrial/metabolismo , Mitocondrias/metabolismo , Nucleotidiltransferasas/metabolismo , Transducción de Señal , Hematopoyesis/efectos de la radiación , Traumatismos Experimentales por Radiación/metabolismo
7.
Cytotechnology ; 74(6): 657-667, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36389286

RESUMEN

Pancreatic cancer is one of the deadliest malignancies. Three-dimensional (3D) pancreatic cancer cell models for drug screening have been established to improve treatment for pancreatic cancer. However, few studies focus on different drug responses and drug-related molecular mechanisms in various types of 3D cell models. In this study, we constructed 3D scaffold-free cell models and 3D scaffold-based cell models of pancreatic cancer, evaluated chemotherapeutic drug responses in different 3D models, assessed clinical relevance of the models, and investigated molecular mechanisms of chemoresistance and drug pathways in different 3D models. Both types of 3D models showed resistance to chemotherapeutic drugs, and scaffold-based pancreatic cancer models could better reflect in vivo drug efficacy than 2D and scaffold-free pancreatic cancer models did. Increased cell adhesion, extracellular matrix (ECM) synthesis and drug transport were essential for drug resistance in 3D models, and anti-apoptosis might contribute to extreme chemoresistance in scaffold-free models. Moreover, scaffold-based pancreatic cancer models were more suitable than scaffold-free models for drug pathway research.

8.
Front Public Health ; 10: 1031743, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36388350

RESUMEN

Exposure to environmental ionizing radiation (IR) is ubiquitous, and large-dose exposure to IR is known to cause DNA damage and genotoxicity which is associated with an increased risk of cancer. Whether such detrimental effects are caused by exposure to low-dose IR is still debated. Therefore, rapid and early estimation of absorbed doses of IR in individuals, especially at low levels, using radiation response markers is a pivotal step for early triage during radiological incidents to provide adequate and timely clinical interventions. However, there is currently a crucial shortage of methods capable of determining the extent of low-dose IR exposure to human beings. The phosphorylation of histone H2AX on serine 139 (designated γ-H2AX), a classic biological dosimeter, can be used to evaluate the DNA damage response. We have developed an estimation assay for low-level exposure to IR based on the mass spectrometry quantification of γ-H2AX in blood. Human peripheral blood lymphocytes sensitive to low-dose IR, maintaining low temperature (4°C) and adding enzyme inhibitor are proven to be key steps, possibly insuring that a stable and marked γ-H2AX signal in blood cells exposed to low-dose IR could be detected. For the first time, DNA damage at low dose exposures to IR as low as 0.01 Gy were observed using the sensitive variation of γ-H2AX with high throughput mass spectrometry quantification in human peripheral blood, which is more accurate than the previously reported methods by virtue of isotope-dilution mass spectrometry, and can observe the time effect of DNA damage. These in vitro cellular dynamic monitoring experiments show that DNA damage occurred rapidly and then was repaired slowly over the passage of post-irradiation time even after exposure to very low IR doses. This assay was also used to assess different radiation exposures at the in vitro cellular level. These results demonstrate the potential utility of this assay in radiation biodosimetry and environmental risk assessment.


Asunto(s)
Linfocitos , Radiación Ionizante , Humanos , Relación Dosis-Respuesta en la Radiación , Linfocitos/efectos de la radiación , Daño del ADN , Espectrometría de Masas
9.
J Transl Med ; 20(1): 456, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36199069

RESUMEN

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) is a critical event contributing to more aggressive phenotypes in cancer cells. EMT is frequently activated in radiation-targeted cells during the course of radiotherapy, which often endows cancers with acquired radioresistance. However, the upstream molecules driving the signaling pathways of radiation-induced EMT have not been fully delineated. METHODS: In this study, RNA-seq-based transcriptome analysis was performed to identify the early responsive genes of HeLa cells to γ-ray irradiation. EMT-associated genes were knocked down by siRNA technology or overexpressed in HeLa cells and A549 cells, and the resulting changes in phenotypes of EMT and radiosensitivity were assessed using qPCR and Western blotting analyses, migration assays, colony-forming ability and apoptosis of flow cytometer assays. RESULTS: Through RNA-seq-based transcriptome analysis, we found that LPAR5 is downregulated in the early response of HeLa cells to γ-ray irradiation. Radiation-induced alterations in LPAR5 expression were further revealed to be a bidirectional dynamic process in HeLa and A549 cells, i.e., the early downregulating phase at 2 ~ 4 h and the late upregulating phase at 24 h post-irradiation. Overexpression of LPAR5 prompts EMT programing and migration of cancer cells. Moreover, increased expression of LPAR5 is significantly associated with IR-induced EMT and confers radioresistance to cancer cells. Knockdown of LPAR5 suppressed IR-induced EMT by attenuating the activation of ERK signaling and downstream Snail, MMP1, and MMP9 expression. CONCLUSIONS: LPAR5 is an important upstream regulator of IR-induced EMT that modulates the ERK/Snail pathway. This study provides further insights into understanding the mechanism of radiation-induced EMT and identifies promising targets for improving the effectiveness of cancer radiation therapy.


Asunto(s)
Metaloproteinasa 1 de la Matriz , Neoplasias , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/genética , Células HeLa , Humanos , Metaloproteinasa 9 de la Matriz , ARN Interferente Pequeño , Receptores del Ácido Lisofosfatídico
10.
Brief Bioinform ; 23(3)2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35238349

RESUMEN

Inhibition of host protein functions using established drugs produces a promising antiviral effect with excellent safety profiles, decreased incidence of resistant variants and favorable balance of costs and risks. Genomic methods have produced a large number of robust host factors, providing candidates for identification of antiviral drug targets. However, there is a lack of global perspectives and systematic prioritization of known virus-targeted host proteins (VTHPs) and drug targets. There is also a need for host-directed repositioned antivirals. Here, we integrated 6140 VTHPs and grouped viral infection modes from a new perspective of enriched pathways of VTHPs. Clarifying the superiority of nonessential membrane and hub VTHPs as potential ideal targets for repositioned antivirals, we proposed 543 candidate VTHPs. We then presented a large-scale drug-virus network (DVN) based on matching these VTHPs and drug targets. We predicted possible indications for 703 approved drugs against 35 viruses and explored their potential as broad-spectrum antivirals. In vitro and in vivo tests validated the efficacy of bosutinib, maraviroc and dextromethorphan against human herpesvirus 1 (HHV-1), hepatitis B virus (HBV) and influenza A virus (IAV). Their drug synergy with clinically used antivirals was evaluated and confirmed. The results proved that low-dose dextromethorphan is better than high-dose in both single and combined treatments. This study provides a comprehensive landscape and optimization strategy for druggable VTHPs, constructing an innovative and potent pipeline to discover novel antiviral host proteins and repositioned drugs, which may facilitate their delivery to clinical application in translational medicine to combat fatal and spreading viral infections.


Asunto(s)
Antivirales , Virus de la Influenza A , Antivirales/farmacología , Antivirales/uso terapéutico , Dextrometorfano , Humanos , Virus de la Influenza A/genética
11.
Int J Mol Sci ; 22(21)2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34768749

RESUMEN

Understanding miRNAs regulatory roles in epithelial-mesenchymal transition (EMT) would help establish new avenues for further uncovering the mechanisms underlying radiation-induced pulmonary fibrosis (RIPF) and identifying preventative and therapeutic targets. Here, we demonstrated that miR-541-5p repression by Myeloid Zinc Finger 1 (MZF1) promotes radiation-induced EMT and RIPF. Irradiation could decrease miR-541-5p expression in vitro and in vivo and inversely correlated to RIPF development. Ectopic miR-541-5p expression suppressed radiation-induced-EMT in vitro and in vivo. Knockdown of Slug, the functional target of miR-541-5p, inhibited EMT induction by irradiation. The upregulation of transcription factor MZF1 upon irradiation inhibited the expression of endogenous miR-541-5p and its primary precursor (pri-miR-541-5p), which regulated the effect of the Slug on the EMT process. Our finding showed that ectopic miR-541-5p expression mitigated RIPF in mice by targeting Slug. Thus, irradiation activates MZF1 to downregulate miR-541-5p in alveolar epithelial cells, promoting EMT and contributing to RIPF by targeting Slug. Our observation provides further understanding of the development of RIPF and determines potential preventative and therapeutic targets.


Asunto(s)
Transición Epitelial-Mesenquimal/efectos de la radiación , MicroARNs/genética , Fibrosis Pulmonar/genética , Células A549 , Células Epiteliales Alveolares/metabolismo , Animales , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/genética , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Pulmón/metabolismo , Pulmón/fisiología , Lesión Pulmonar/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Fibrosis Pulmonar/metabolismo , Síndrome de Fibrosis por Radiación/genética , Transducción de Señal/fisiología , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , Factores de Transcripción/metabolismo
12.
Cell Death Discov ; 7(1): 260, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34552057

RESUMEN

To maintain genomic stability, the mammalian cells has evolved a coordinated response to DNA damage, including activation of DNA repair and cell cycle checkpoint processes. Exonuclease 1 (EXO1)-dependent excision of DNA ends is important for the initiation of homologous recombination (HR) repair of DNA breaks, which is thought to play a key role in activating the ATR-CHK1 pathway to induce G2/M cell cycle arrest. But the mechanism is still not fully understood. Here, we report that ZGRF1 forms complexes with EXO1 as well as other repair proteins and promotes DNA repair through HR. ZGRF1 is recruited to DNA damage sites in a MDC1-RNF8-BRCA1 dependent manner. Furthermore, ZGRF1 is important for the recruitment of RPA2 to DNA damage sites and the following ATR-CHK1 mediated G2/M checkpoint in response to irradiation. ZGRF1 null cells show increased sensitivity to many DNA-damaging agents, especially PARPi and irradiation. Collectively,our findings identify ZGRF1 as a novel regulator of DNA end resection and G2/M checkpoint. ZGRF1 is a potential target of radiation and PARPi cancer therapy.

13.
Int J Mol Med ; 47(5)2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33693953

RESUMEN

Radioresistance is the predominant cause for radiotherapy failure and disease progression, resulting in increased breast cancer­associated mortality. Using gene expression signature analysis of the Library of Integrated Network­Based Cellular Signatures (LINCS) and Gene Expression Omnibus (GEO), the aim of the present study was to systematically identify potential candidate radiosensitizers from known drugs. The similarity of integrated gene expression signatures between irradiated eukaryotic translation initiation factor 4 Î³ 1 (eIF4G1)­silenced breast cancer cells and known drugs was measured using enrichment scores (ES). Drugs with positive ES were selected as potential radiosensitizers. The radiosensitizing effects of the candidate drugs were analyzed in breast cancer cell lines (MCF­7, MX­1 and MDA­MB­231) using CCK­8 and colony formation assays following exposure to ionizing radiation. Cell apoptosis was measured using flow cytometry. The expression levels of eIF4G1 and DNA damage response (DDR) proteins were analyzed by western blotting. Bosutinib was identified as a promising radiosensitizer, as its administration markedly reduced the dosage required both for the drug and for ionizing radiation, which may be associated with fewer treatment­associated adverse reactions. Moreover, combined treatment of ionizing radiation and bosutinib significantly increased cell killing in all three cell lines, compared with ionizing radiation or bosutinib alone. Among the three cell lines, MX­1 cells were identified as the most sensitive to both ionizing radiation and bosutinib. Bosutinib markedly downregulated the expression of eIF4G1 in a dose­dependent manner and also reduced the expression of DDR proteins (including ATM, XRCC4, ATRIP, and GADD45A). Moreover, eIF4G1 was identified as a key target of bosutinib that may regulate DNA damage induced by ionizing radiation. Thus, bosutinib may serve as a potential candidate radiosensitizer for breast cancer therapy.


Asunto(s)
Compuestos de Anilina/farmacología , Neoplasias de la Mama/metabolismo , Bases de Datos de Ácidos Nucleicos , Factor 4G Eucariótico de Iniciación/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Neoplasias/metabolismo , Nitrilos/farmacología , Quinolinas/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Transcriptoma/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Factor 4G Eucariótico de Iniciación/genética , Femenino , Humanos , Proteínas de Neoplasias/genética
14.
Life (Basel) ; 10(12)2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33352926

RESUMEN

Ionizing radiation causes serious injury to the human body and has long-time impacts on health. It is important to find optimal biomarkers for the early quick screening of exposed individuals. A series of miRNAs signatures have been developed as the new biomarkers for diagnosis, survival, and prognostic prediction of cancers. Here, we have identified the ionizing radiation-inducible miRNAs profile through microarray analysis. The biological functions were predicted for the top six upregulated miRNAs by 4 Gy γ-rays: miR-1246, miR-1307-3p, miR-3197, miR-4267, miR-5096 and miR-7641. The miRNA-gene network and target gene-pathway network analyses revealed that DNAH3 is the target gene associated with all the six miRNAs. GOLGB1 is related to 4 miRNAs and other 26 genes targeted by 3 miRNAs. The upregulation of fifteen miRNAs were further verified at 4 h and 24 h after 0 to 10 Gy irradiation in the human lymphoblastoid AHH-1 cells, and some demonstrated a dose-dependent increased. Six miRNAs, including miR-145, miR-663, miR-1273g-3p, miR-6090, miR-6727-5p and miR-7641, were validated to be dose-dependently upregulated at 4 h or 24 h post-irradiation in both AHH-1 and human peripheral blood lymphocytes irradiated ex vivo. This six-miRNA signature displays the superiority as a radiation biomarker for the translational application of screening and assessment of radiation exposed individuals.

15.
Sci Adv ; 6(28): eaba7822, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32832608

RESUMEN

Nonhomologous end joining (NHEJ) and homologous recombination (HR) are major repair pathways of DNA double-strand breaks (DSBs). The pathway choice of HR and NHEJ is tightly regulated in cellular response to DNA damage. Here, we demonstrate that the interaction of TIP60 with DNA-PKcs is attenuated specifically in S phase, which facilitates HR pathway activation. SUMO2 modification of TIP60 K430 mediated by PISA4 E3 ligase blocks its interaction with DNA-PKcs, whereas TIP60 K430R mutation recovers its interaction with DNA-PKcs, which results in abnormally increased phosphorylation of DNA-PKcs S2056 in S phase and marked inhibition of HR efficiency, but barely affects NHEJ activity. TIP60 K430R mutant cancer cells are more sensitive to radiation and PARP inhibitors in cancer cell killing and tumor growth inhibition. Collectively, coordinated regulation of TIP60 and DNA-PKcs facilitates HR pathway choice in S-phase cells. TIP60 K430R mutant is a potential target of radiation and PARPi cancer therapy.


Asunto(s)
Reparación del ADN , Neoplasias , ADN/genética , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , Recombinación Homóloga , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Sumoilación
16.
Cell Death Dis ; 11(5): 400, 2020 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-32457294

RESUMEN

DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is the core component of DNA-PK complex in the non-homologous end-joining (NHEJ) repair of DNA double-strand breaks, and its activity is strictly controlled by DNA-PKcs phosphorylation. The ubiquitin-like protein, NEDD8 is involved in regulation of DNA damage response, but it remains mysterious whether and how NEDD8-related neddylation affects DNA-PKcs and the NHEJ process. Here, we show that DNA-PKcs is poly-neddylated at its kinase domain. The neddylation E2-conjugating enzyme UBE2M and E3 ligase HUWE1 (HECT, UBA, and WWE domain containing E3 ubiquitin protein ligase 1) are responsible for the DNA-PKcs neddylation. Moreover, inhibition of HUWE1-dependent DNA-PKcs neddylation impairs DNA-PKcs autophosphorylation at Ser2056. Finally, depletion of HUWE1-dependent DNA-PKcs neddylation reduces the efficiency of NHEJ. These studies provide insights how neddylation modulates the activity of NHEJ core complex.


Asunto(s)
Daño del ADN , Proteína Quinasa Activada por ADN/metabolismo , Proteína NEDD8/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Línea Celular , Reparación del ADN por Unión de Extremidades , Proteína Quinasa Activada por ADN/química , Humanos , Fosforilación , Fosfoserina/metabolismo , Dominios Proteicos
17.
Front Genet ; 11: 607428, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33424929

RESUMEN

DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is a member of the phosphatidylinositol 3-kinase related kinase family, which can phosphorylate more than 700 substrates. As the core enzyme, DNA-PKcs forms the active DNA-PK holoenzyme with the Ku80/Ku70 heterodimer to play crucial roles in cellular DNA damage response (DDR). Once DNA double strand breaks (DSBs) occur in the cells, DNA-PKcs is promptly recruited into damage sites and activated. DNA-PKcs is auto-phosphorylated and phosphorylated by Ataxia-Telangiectasia Mutated at multiple sites, and phosphorylates other targets, participating in a series of DDR and repair processes, which determine the cells' fates: DSBs NHEJ repair and pathway choice, replication stress response, cell cycle checkpoints, telomeres length maintenance, senescence, autophagy, etc. Due to the special and multi-faceted roles of DNA-PKcs in the cellular responses to DNA damage, it is important to precisely regulate the formation and dynamic of its functional complex and activities for guarding genomic stability. On the other hand, targeting DNA-PKcs has been considered as a promising strategy of exploring novel radiosensitizers and killing agents of cancer cells. Combining DNA-PKcs inhibitors with radiotherapy can effectively enhance the efficacy of radiotherapy, offering more possibilities for cancer therapy.

18.
Cell Death Differ ; 27(4): 1383-1397, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31562368

RESUMEN

End resection of DNA double-strand breaks (DSBs) to form 3' single-strand DNA (ssDNA) is critical to initiate the homologous recombination (HR) pathway of DSB repair. HR pathway is strictly limited in the G1-phase cells because of lack of homologous DNA as the templates. Exonuclease 1 (EXO1) is the key molecule responsible for 3' ssDNA formation of DSB end resection. We revealed that EXO1 is inactivated in G1-phase cells via ubiquitination-mediated degradation, resulting from an elevated expression level of RING-box protein 1 (RBX1) in G1 phase. The increased RBX1 significantly prompted the neddylation of Cullin1 and contributed to the G1 phase-specific degradation of EXO1. Knockdown of RBX1 remarkedly attenuated the degradation of EXO1 and increased the end resection and HR activity in γ-irradiated G1-phase cells, as demonstrated by the increased formation of RPA32, BrdU, and RAD51 foci. And EXO1 depletion mitigated DNA repair defects due to RBX1 reduction. Moreover, increased autophosphorylation of DNA-PKcs at S2056 was found to be responsible for the higher expression level of the RBX1 in the G1 phase. Inactivation of DNA-PKcs decreased RBX1 expression, and simultaneously increased EXO1 expression and DSB end resection in G1-phase cells. This study demonstrates a new mechanism for restraining the HR pathway of DNA DSB repair in G1 phase via RBX1-prompted inactivation of EXO1.


Asunto(s)
Proteínas Portadoras/metabolismo , Roturas del ADN de Doble Cadena , Enzimas Reparadoras del ADN/metabolismo , Reparación del ADN , Exodesoxirribonucleasas/metabolismo , Fase G1 , Recombinación Homóloga , Proteolisis , Línea Celular Tumoral , Supervivencia Celular/efectos de la radiación , Proteínas Cullin/metabolismo , Proteína Quinasa Activada por ADN/metabolismo , Rayos gamma , Humanos , Modelos Biológicos , Recombinasa Rad51/metabolismo , Ubiquitinación
19.
J Cancer ; 10(25): 6466-6474, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31772679

RESUMEN

The establishment of human malignant tumor cell lines can provide abundant experimental materials for understanding the biological characteristics of tumors, studying the carcinogenesis, molecular genetics and the mechanism of metastasis and evolution. In this study, a novel cell line designated ZJB-ENC1 has been established from poorly differentiated endometrioid adenocarcinoma. Cytological results showed monolayer-cultured cells were polygonal in shape and a piling-up tendency without contact inhabitation. Immunohistochemistry analysis showed that the cells were negative for ER, PR, c-erbB2, E-CAD, CD117, and OCT3/4, but strongly positive for PTEN and P16. Meanwhile, the tumorigenicity of ZJB-ENC1 was confirmed by subcutaneous transplantation of the cells into a xenograft mouse model. In addition, the results of the whole exome sequencing revealed a unique genomic characteristic of ZJB-ENC1 cells, all common and novel SNPs and InDels were identified. In conclusion, this new stable cell line may promote basic and clinical research on endometrial cancer (EC).

20.
Dose Response ; 17(1): 1559325819833474, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30833875

RESUMEN

BACKGROUND: Radiation therapy induces acute and chronic radiological toxicity, in particular hematological toxicity (HT). This study aimed to explore the mechanistic clue and potential predictors at the messenger RNA (mRNA) level. MATERIALS AND METHODS: Peripheral blood was collected from 3 patients with cervical cancer (CC), nasopharynx cancer (NC), and tongue cancer (TC) after the first 2 Gy fraction of radiotherapy (RT). High-throughput sequencing was used to assess mRNA profiles. RESULTS: Eleven genes, such as ALAS2(5-aminolevulinate synthase), SLC4A1(solute carrier family 4 member 1), HBG2(hemoglobin subunit gamma 2), TNFAIP3 (TNF α-induced protein 3), PER1 (period circadian clock 1), CCDC136 (coiled-coil domain containing 136), C9orf84 (chromosome 9 open reading frame 84), IL1B (interleukin 1ß), FOSB (FosB protooncogene), NR4A2 (nuclear receptor subfamily 4), PARP15 (polymerase family member 15), had overlapping expression changes in all 3 cancers of which 3 (ALAS2, FOSB, and HBG2) are suggested as potential predictors for the early diagnosis of HT after RT. CONCLUSIONS: ALAS2, FOSB, and HBG2 may be useful predictors of HT in patients after RT. Eleven overlapping expression mRNAs among 3 cancers might be potential predictors for early diagnosis of radiation toxicity in patients.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...