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Tumor cells must rewire nucleotide synthesis to satisfy the demands of unbridled proliferation. Meanwhile, they exhibit augmented reactive oxygen species (ROS) production which paradoxically damages DNA and free deoxy-ribonucleoside triphosphates (dNTPs). How these metabolic processes are integrated to fuel tumorigenesis remains to be investigated. MYC family oncoproteins coordinate nucleotide synthesis and ROS generation to drive the development of numerous cancers. We herein perform a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based functional screen targeting metabolic genes and identified nudix hydrolase 1 (NUDT1) as a MYC-driven dependency. Mechanistically, MYC orchestrates the balance of two metabolic pathways that act in parallel, the NADPH oxidase 4 (NOX4)-ROS pathway and the Polo like kinase 1 (PLK1)-NUDT1 nucleotide-sanitizing pathway. We describe LC-1-40 as a potent, on-target degrader that depletes NUDT1 in vivo. Administration of LC-1-40 elicits excessive nucleotide oxidation, cytotoxicity and therapeutic responses in patient-derived xenografts. Thus, pharmacological targeting of NUDT1 represents an actionable MYC-driven metabolic liability.
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Nucleótidos , Hidrolasas Nudix , Humanos , Especies Reactivas de Oxígeno/metabolismo , Oxidación-Reducción , Nucleótidos/metabolismoRESUMEN
The HIV-1 Tat protein hijacks the Super Elongation Complex (SEC) to stimulate viral transcription and replication. However, the mechanisms underlying Tat activation and inactivation, which mediate HIV-1 productive and latent infection, respectively, remain incompletely understood. Here, through a targeted complementary DNA (cDNA) expression screening, we identify PRMT2 as a key suppressor of Tat activation, thus contributing to proviral latency in multiple cell line latency models and in HIV-1-infected patient CD4+ T cells. Our data reveal that the transcriptional activity of Tat is oppositely regulated by NPM1-mediated nucleolar retention and AFF4-induced phase separation in the nucleoplasm. PRMT2 preferentially methylates Tat arginine 52 (R52) to reinforce its nucleolar sequestration while simultaneously counteracting its incorporation into the SEC droplets, thereby leading to its functional inactivation to promote proviral latency. Thus, our studies unveil a central and unappreciated role for Tat methylation by PRMT2 in connecting its subnuclear distribution, liquid droplet formation, and transactivating function, which could be therapeutically targeted to eradicate latent viral reservoirs.
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Infecciones por VIH , VIH-1 , Humanos , VIH-1/fisiología , Factores de Elongación Transcripcional/metabolismo , Línea Celular , Provirus/genética , Linfocitos T/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/metabolismo , Latencia del Virus/genética , Infecciones por VIH/genética , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismoRESUMEN
The proper regulation of transcription is essential for maintaining genome integrity and executing other downstream cellular functions1,2. Here we identify a stable association between the genome-stability regulator sensor of single-stranded DNA (SOSS)3 and the transcription regulator Integrator-PP2A (INTAC)4-6. Through SSB1-mediated recognition of single-stranded DNA, SOSS-INTAC stimulates promoter-proximal termination of transcription and attenuates R-loops associated with paused RNA polymerase II to prevent R-loop-induced genome instability. SOSS-INTAC-dependent attenuation of R-loops is enhanced by the ability of SSB1 to form liquid-like condensates. Deletion of NABP2 (encoding SSB1) or introduction of cancer-associated mutations into its intrinsically disordered region leads to a pervasive accumulation of R-loops, highlighting a genome surveillance function of SOSS-INTAC that enables timely termination of transcription at promoters to constrain R-loop accumulation and ensure genome stability.
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Inestabilidad Genómica , Regiones Promotoras Genéticas , Estructuras R-Loop , Terminación de la Transcripción Genética , Humanos , ADN de Cadena Simple/metabolismo , Inestabilidad Genómica/genética , Mutación , Estructuras R-Loop/genética , ARN Polimerasa II/metabolismo , Regiones Promotoras Genéticas/genética , Genoma Humano , Proteínas de Unión al ADN/metabolismoRESUMEN
Cyclin-dependent kinase 12 (CDK12) interacts with cyclin K to form a functional nuclear kinase that promotes processive transcription elongation through phosphorylation of the C-terminal domain of RNA polymerase II (Pol II). To gain a comprehensive understanding of CDK12's cellular function, we used chemical genetic and phosphoproteomic screening to identify a landscape of nuclear human CDK12 substrates, including regulators of transcription, chromatin organization, and RNA splicing. We further validated LEO1, a subunit of the polymerase-associated factor 1 complex (PAF1C), as a bona fide cellular substrate of CDK12. Acute depletion of LEO1, or substituting LEO1 phosphorylation sites with alanine, attenuated PAF1C association with elongating Pol II and impaired processive transcription elongation. Moreover, we discovered that LEO1 interacts with and is dephosphorylated by the Integrator-PP2A complex (INTAC) and that INTAC depletion promotes the association of PAF1C with Pol II. Together, this study reveals an uncharacterized role for CDK12 and INTAC in regulating LEO1 phosphorylation, providing important insights into gene transcription and its regulation.
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Quinasas Ciclina-Dependientes , ARN Polimerasa II , Humanos , Fosforilación/genética , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , ARN Polimerasa II/metabolismo , Núcleo Celular/metabolismo , Transcripción Genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
MYCN amplification in neuroblastoma leads to aberrant expression of MYCN oncoprotein, which binds active genes promoting transcriptional amplification. Yet, how MYCN coordinates transcription elongation to meet productive transcriptional amplification and which elongation machinery represents MYCN-driven vulnerability remain to be identified. We conducted a targeted screen of transcription elongation factors and identified the super elongation complex (SEC) as a unique vulnerability in MYCN-amplified neuroblastomas. MYCN directly binds EAF1 and recruits SEC to enhance processive transcription elongation. Depletion of EAF1 or AFF1/AFF4, another core subunit of SEC, leads to a global reduction in transcription elongation and elicits selective apoptosis of MYCN-amplified neuroblastoma cells. A combination screen reveals SEC inhibition synergistically potentiates the therapeutic efficacies of FDA-approved BCL-2 antagonist ABT-199, in part due to suppression of MCL1 expression, both in MYCN-amplified neuroblastoma cells and in patient-derived xenografts. These findings identify disruption of the MYCN-SEC regulatory axis as a promising therapeutic strategy in neuroblastoma.
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Neuroblastoma , Proteínas Nucleares , Humanos , Proteína Proto-Oncogénica N-Myc/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Oncogénicas , Factores de Elongación Transcripcional/genética , Factores de Elongación Transcripcional/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Factores de TranscripciónRESUMEN
BACKGROUND: G-quadruplexes (G4s) are unique noncanonical nucleic acid secondary structures, which have been proposed to physically interact with transcription factors and chromatin remodelers to regulate cell type-specific transcriptome and shape chromatin landscapes. RESULTS: Based on the direct interaction between G4 and natural porphyrins, we establish genome-wide approaches to profile where the iron-liganded porphyrin hemin can bind in the chromatin. Hemin promotes genome-wide G4 formation, impairs transcription initiation, and alters chromatin landscapes, including decreased H3K27ac and H3K4me3 modifications at promoters. Interestingly, G4 status is not involved in the canonical hemin-BACH1-NRF2-mediated enhancer activation process, highlighting an unprecedented G4-dependent mechanism for metabolic regulation of transcription. Furthermore, hemin treatment induces specific gene expression profiles in hepatocytes, underscoring the in vivo potential for metabolic control of gene transcription by porphyrins. CONCLUSIONS: These studies demonstrate that G4 functions as a sensor for natural porphyrin metabolites in cells, revealing a G4-dependent mechanism for metabolic regulation of gene transcription and chromatin landscapes, which will deepen our knowledge of G4 biology and the contribution of cellular metabolites to gene regulation.
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G-Cuádruplex , Porfirinas , Cromatina , Hemina/química , Transcripción GenéticaRESUMEN
G-quadruplexes (G4s) are noncanonical DNA secondary structures formed through the self-association of guanines, and G4s are distributed widely across the genome. G4 participates in multiple biological processes including gene transcription, and G4-targeted ligands serve as potential therapeutic agents for DNA-targeted therapies. However, genome-wide studies of the exact roles of G4s in transcriptional regulation are still lacking. Here, we establish a sensitive G4-CUT&Tag method for genome-wide profiling of native G4s with high resolution and specificity. We find that native G4 signals are cell type-specific and are associated with transcriptional regulatory elements carrying active epigenetic modifications. Drug-induced promoter-proximal RNA polymerase II pausing promotes nearby G4 formation. In contrast, G4 stabilization by G4-targeted ligands globally reduces RNA polymerase II occupancy at gene promoters as well as nascent RNA synthesis. Moreover, ligand-induced G4 stabilization modulates chromatin states and impedes transcription initiation via inhibition of general transcription factors loading to promoters. Together, our study reveals a reciprocal genome-wide regulation between native G4 dynamics and gene transcription, which will deepen our understanding of G4 biology toward therapeutically targeting G4s in human diseases.
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G-Cuádruplex , Iniciación de la Transcripción Genética , Cromatina , ADN/química , Ligandos , Regiones Promotoras GenéticasRESUMEN
An R loop is a unique triple-stranded structure that participates in multiple key biological processes and is relevant to human diseases. Accurate and comprehensive R loop profiling is a prerequisite for R loops studies. However, current R loop mapping methods generate large discrepancies, therefore an independent method is in urgent need. Here, we establish an independent R loop CUT&Tag (Tn5-based cleavage under targets and tagmentation) method by combining CUT&Tag and GST-His6-2×HBD (glutathione S-transferase-hexahistidine-2× hybrid-binding domain), an artificial DNA-RNA hybrid sensor that specifically recognizes the DNA-RNA hybrids. We demonstrate that the R loop CUT&Tag is sensitive, reproducible, and convenient for native R loop mapping with high resolution, and find that the capture strategies, instead of the specificity of sensors, largely contribute to the disparities among different methods. Together, we provide an independent strategy for genomic profiling of native R loops and help resolve discrepancies among multiple R loop mapping methods.
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Estructuras R-Loop , ARN , ADN/química , Humanos , ARN/química , ARN/genéticaRESUMEN
The NAD-dependent deacetylase Sirtuin 1 (SIRT1) plays a vital role in leukemogenesis. Nicotinamide (NAM) is the principal NAD+ precursor and a noncompetitive inhibitor of SIRT1. In our study, we showed that NAM enhanced the sensitivity of chronic myeloid leukemia (CML) to doxorubicin (DOX) via SIRT1. We found that SIRT1 high expression in CML patients was associated with disease progression and drug resistance. Exogenous NAM efficiently repressed the deacetylation activity of SIRT1 and induced the apoptosis of DOX-resistant K562 cells (K562R) in a dose-dependent manner. Notably, the combination of NAM and DOX significantly inhibited tumor cell proliferation and induced cell apoptosis. The knockdown of SIRT1 in K562R cells enhanced NAM+DOX-induced apoptosis. SIRT1 rescue in K562R reduced the NAM+DOX-induced apoptosis. Mechanistically, the combinatory treatment significantly increased the cleavage of caspase-3 and PARP in K562R in vitro and in vivo. These results suggest the potential role of NAM in increasing the sensitivity of CML to DOX via the inhibition of SIRT1.
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Doxorrubicina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Niacinamida/farmacología , Sirtuina 1/antagonistas & inhibidores , Animales , Antibióticos Antineoplásicos/farmacología , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Combinación de Medicamentos , Sinergismo Farmacológico , Femenino , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Ratones , Ratones SCID , Sirtuina 1/genética , Sirtuina 1/metabolismo , Células Tumorales Cultivadas , Complejo Vitamínico B/farmacología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Myeloid-derived suppressor cells (MDSCs), a heterogeneous population of myeloid cells, are characterized by their immunosuppressive abilities through the secretion of various cytokines such as inducible nitric oxide synthase, nitric oxide, reactive oxygen species, transforming growth factor-ß, and arginase-1. Accumulating evidence highlights its potential role in maintaining immune tolerance in solid organ and hematopoietic stem cell transplantation. Mechanistically, MDSCs-induced transplant tolerance is mainly dependent on direct suppression of allogeneic reaction or strengthened cross-talk between MDSCs and Treg or NKT cells. Adopted transfer of in vitro- or in vivo-induced MDSCs by special drugs therefore becomes a potential strategy for maintaining transplantation tolerance. In this review, we will summarize the previously published data about the role of MDSCs in the biology of transplantation tolerance and gain insights into the possible molecular mechanism governing this process.
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Traslado Adoptivo/métodos , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/inmunología , Células Supresoras de Origen Mieloide/inmunología , Tolerancia al Trasplante , Animales , Modelos Animales de Enfermedad , Rechazo de Injerto/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Células Supresoras de Origen Mieloide/trasplante , Trasplante de Órganos/efectos adversosRESUMEN
Natural fiber reinforced polymer-based composites have been growing into a type of green composites. The properties of natural fiber reinforced polymer-based composites are closely related to the structure of natural fibers. Bagasse fiber (BF) is one of the most used natural fibers for preparing natural fiber reinforced polymer-based composites. However, few examples of previous research touch on the quantitatively characterization of structure of BF and its effect on the properties of BF reinforced polymer-based composites. In this work, four kinds of BF including untreated BF (UBF), alkali treated BF (ABF), BF modified by silane coupling agent (SBF), and BF modified combining alkali treatment with silane coupling agent (ASBF) were prepared and melting blended with polylactic acid (PLA) to prepare PLA/BF composites. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thermogravimetry (TGA) and mechanical properties testing were used to characterize and analyze the structure and properties of modified BF and its reinforced PLA-based composites. Results showed that the used methods changed the structure of BF and their bonding modes. The surface energies of UBF, ABF, SBF, and ASBF were 19.8 mJ/m2, 34.7 mJ/m2, 12.3 mJ/m2, and 21.6 mJ/m2, respectively. The O/C ratios of UBF, ABF, SBF and, ASBF are 0.48, 0.53, 0.47, and 0.51. Due to the synergistic effect of alkali treatment and silane coupling agent modification on the surface chemical properties, the content of silicon elements on the surface of ASBF (4.15%) was higher than that of ASBF (2.38%). However, due to the destroying of alkali treatment on the microstructure of BF, the alkali treatment had no prominently synergetic effect with coupling agent modification on the mechanical properties of PLA/BF composites. Alkali treatment removed the small molecular compounds from BF, decreased its thermal stability, and increased the crystalline region and crystallinity of cellulose. Meanwhile, alkali treatment made BF fibrillated and increased its contactable active area with the coupling agents, but destructed the nature structure of BF. The silane coupling agent played a more important role than alkali treatment did in improving the interfacial compatibility of PLA/BF composites.
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Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is the only curative treatment for multiple hematologic malignancies and non-malignant hematological diseases. However, graft-vs.-host disease (GVHD), one of the main complications after allo-HSCT, remains the major reason for morbidity and non-relapse mortality. Emerging evidence has demonstrated that innate lymphoid cells (ILCs) play a non-redundant role in the pathophysiology of GVHD. In this review, we will summarize previously published data regarding the role of ILCs in the pathogenesis of GVHD.
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Susceptibilidad a Enfermedades , Enfermedad Injerto contra Huésped/genética , Enfermedad Injerto contra Huésped/metabolismo , Inmunidad Innata , Linfocitos/inmunología , Linfocitos/metabolismo , Biomarcadores , Plasticidad de la Célula/inmunología , Regulación de la Expresión Génica , Humanos , Inmunofenotipificación , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Transcripción GenéticaRESUMEN
Metastatic disease remains the primary cause of death for individuals with T cell acute lymphoblastic leukemia (T-ALL). microRNAs (miRNAs) play important roles in the pathogenesis of T-ALL by inhibiting gene expression at posttranscriptional levels. The goal of the current project is to identify any significant miRNAs in T-ALL metastasis. We observed miR-146b-5p to be downregulated in T-ALL patients and cell lines, and bioinformatics analysis implicated miR-146b-5p in the hematopoietic system. miR-146b-5p inhibited the migration and invasion in T-ALL cells. Interleukin-17A (IL-17A) was predicted to be a target of miR-146b-5p; this was confirmed by luciferase assays. Interestingly, T-ALL patients and cell lines secreted IL-17A and expressed the IL-17A receptor (IL-17RA). IL-17A/IL-17RA interactions promoted strong T-ALL cell migration and invasion responses. Gene set enrichment analysis (GSEA) and quantitative polymerase chain reaction (qPCR) analysis indicated that matrix metallopeptidase-9 (MMP9), was a potential downstream effector of IL-17A activation, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling was also implicated in this process. Moreover, IL-17A activation promoted T-ALL cell metastasis to the liver in IL17A -/- mouse models. These results indicate that reduced miR-146b-5p expression in T-ALL may lead to the upregulation of IL-17A, which then promotes T-ALL cell migration and invasion by upregulating MMP9 via NF-κB signaling.
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Interleucina-17/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Linfocitos T/metabolismo , Animales , Apoptosis/genética , Apoptosis/fisiología , Western Blotting , Ciclo Celular/genética , Ciclo Celular/fisiología , Línea Celular Tumoral , Movimiento Celular/genética , Movimiento Celular/fisiología , Proliferación Celular/genética , Proliferación Celular/fisiología , Biología Computacional , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Interleucina-17/genética , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs , Reacción en Cadena en Tiempo Real de la Polimerasa , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Mixed lineage leukemia (MLL) is an aggressive and refractory blood cancer that predominantly occurs in pediatric patients and is often associated with poor prognosis and dismal outcomes. Thus far, no effective target therapy for the treatment of MLL leukemia is available. MLL leukemia is caused by the rearrangement of MLL genes at 11q23, which generates various MLL chimeric proteins that promote leukemogenesis through transcriptional misregulation of MLL target genes. Biochemical studies on MLL chimeras have identified that the most common partners exist in the superelongation complex (SEC) and DOT1L complex, which activate or sustain MLL target gene expression through processive transcription elongation. The results of these studies indicate a transcription-related mechanism for MLL leukemogenesis and maintenance. In this study, we first review the history of MLL leukemia and its related clinical features. Then, we discuss the biological functions of MLL and MLL chimeras, significant cooperating events, and transcriptional addiction mechanisms in MLL leukemia with an emphasis on potential and rational therapy development. Collectively, we believe that targeting the transcriptional addiction mediated by SEC and the DOT1L complex will provide new avenues for target therapies in MLL leukemia and serve as a novel paradigm for targeting transcriptional addiction in other cancers.
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BACKGROUND: ZWINT is a crucial component of the mitotic checkpoint. However, its possible role in lung cancer is unclear. In this study, we determined its correlation with lung cancer. METHODS: Real-time PCR and immunohistochemistry (IHC) were used to determine 40 collected clinical lung cancer samples. Chi-square test was used to examine possible correlations between ZWINT expression and clinicopathological factors. The prognostic significance of mRNA expression of ZWINT in lung cancer was evaluated using the Kaplan-Meier plotter. Univariate and multivariate Cox proportional hazards regression analysis were performed to determine whether ZWINT is an independent risk factor for overall survival (OS) and disease-free survival (DFS) of lung cancer patients. Additionally, STRING database was used to analyze protein-protein interactions. RESULTS: In this study, we screened 13 GSE datasets and detected that ZWINT is highly expressed in multiple carcinomas including lung, melanoma, prostate, nasopharyngeal, gastric, pancreatic, colon, esophageal, ovarian, renal, breast and liver cancer. Real-time PCR and IHC results of collected clinical lung cancer samples confirmed that ZWINT is highly expressed in tumor tissues compared with adjacent non-tumor tissues. Additionally, high expression of ZWINT might predict poor OS and DFS in lung cancer patients. Moreover, disease stage and expression level of ZWINT were correlated with recurrence-free survival and OS in lung cancer. Analysis of protein-protein interaction based on STRING database gained 8 top genes which could interact with ZWINT, including PMF1, MIS12, DSN1, ZW10, BUB1, BUB1B, CASC5, NDC80, NSL1 and NUF2. CONCLUSION: ZWINT is aberrantly highly expressed in lung tumor tissues and might be involved in the pathogenesis of lung cancer.
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Baicalein, a type of flavonoids extracted from Scutellaria baicalensis Georgi, has been reported to be a very promising drug for pancreatic cancer. However, it is unclear whether combination of baicalein with gemcitabine or docetaxel is synergistic to the treatment for pancreatic cancer (PC). We investigated the combinational effects of baicalein with gemcitabine or docetaxel on proliferation, cell cycle, migration and apoptosis of human PC cells. Administration of baicalein alone significantly inhibit the proliferation of PC cells. Notably, when it is combined with gemcitabine or docetaxel, combination index (CI) values calculated by Calcusyn software are smaller than 1, indicating the synergism of baicalein with gemcitabine or docetaxel for the treatment of PC cells. Consistently, EdU assay showed that administration of baicalein significantly enhanced the capacity of gemicitabine to inhibit proliferation of PC cells. Cell cycle analysis showed that high-concentration of baicalein was able to arrest PC cells in the S phase. Furthermore, low concentration of baicalein in combination with either gemcitabine or docetaxel exhibited strong suppression on the migration of PC cells. A further study using transmission electron microscope (TEM), DAPI staining and western blot showed that baicalein induced-apoptosis of PC cells might be via caspase-3/PARP signaling pathway. Notably, combination treatment was able to induce more severe cell apoptosis of PC cells. In conclusion, baicalein exhibited synergistic effects with gemcitabine or docetaxel on the treatment of PC cells.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Desoxicitidina/análogos & derivados , Flavanonas/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Taxoides/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Desoxicitidina/administración & dosificación , Desoxicitidina/farmacología , Docetaxel , Sinergismo Farmacológico , Flavanonas/administración & dosificación , Humanos , Neoplasias Pancreáticas/patología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Taxoides/administración & dosificación , GemcitabinaRESUMEN
T-cell acute lymphoblastic leukemia (T-ALL) represents a spectrum of hematological malignancies that affect human health. Metastasis and chemotherapeutic drug resistance are the primary causes of mortality in patients with T-ALL. Sodium-hydrogen antiporter 1 (NHE1) is established to serve a role in metastasis and drug resistance in numerous types of cancer; however, the function of NHE1 in T-ALL remains to be elucidated. Previously, the C-C-motif chemokine ligand 25 (CCL25) was identified to be involved in metastasis and drug resistance in the MOLT4 T-ALL cell line, as was the ezrin protein. The present study investigated the role of NHE1 in the metastasis of T-ALL using a Transwell assay and scanning electron microscopy, using MOLT4 cells as a model. The association between NHE1 and ezrin was assessed using laser scanning confocal microscopy. The effect of NHE1 on resistance to the chemotherapy drug doxorubicin (DOX) was also investigated using a cell viability and cytotoxicity assay. Expression of NHE1 increased following treatment with CCL25, accompanied by morphological changes in MOLT4 cells and the co-localization of NHE1 with ezrin. In addition, wild-type MOLT4 cells exhibited an increased polarization ability compared with NHE1- or ezrin-silenced cells. NHE1- or ezrin-silenced cells exhibited higher sensitivity to DOX compared with wild-type MOLT4 cells. In conclusion, the increased expression or activity of NHE1 may potentially be a poor prognostic indicator for human T-ALL.
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Tripartite motif containing 28 (TRIM28) is a transcriptional regulator acting as an essential corepressor for Krüppel-associated box zinc finger domain-containing proteins in multiple tissue and cell types. An increasing number of studies have investigated the function of TRIM28; however, its prognostic value in breast cancer (BC) remains unclear. In the present study, the expression of TRIM28 was identified to be significantly higher in cancerous compared with healthy tissue samples. Furthermore, it was demonstrated that TRIM28 expression was significantly correlated with several clinicopathological characteristics of patients with BC, such as p53 mutation, tumor recurrence and Elston grade of the tumor. In addition, a protein-protein interaction network was created to illustrate the interactions of TRIM28 with other proteins. The prognostic value of TRIM28 in patients with BC was investigated using the Kaplan-Meier Plotter database, which revealed that high expression of TRIM28 is a predictor of poor prognosis in patients with BC. In conclusion, the results of the present study indicate that TRIM28 provides a survival advantage to patients with BC and is a novel prognostic biomarker, in addition to being a therapeutic target for the treatment of BC.
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Adult T-cell acute lymphoblastic leukemia (T-ALL) is a refractory leukemia. We previously showed that CCL25/CCR9 promotes T-ALL metastasis. In the present study, we assessed the effects of CCL25 on Wnt expression and the effects of Wnt5a and CCL25 on PI3K/Akt and RhoA activation. Transwell assays and mouse xenograft experiments were utilized to assess the effects of Wnt5a and CCL25 on MOLT4 cell invasion, migration and metastasis. The effects of Wnt5a on MOLT4 cell actin polarization and pseudopodium formation were examined using laser scanning confocal microscopy and scanning electron microscopy. CCL25 induced Wnt5a expression in MOLT4 cells by promoting protein kinase C (PKC) expression and activation. Wnt5a promoted MOLT4 cell migration, invasion, actin polarization, and lamellipodium and filopodia formation via PI3K/Akt-RhoA pathway activation. These effects were rescued by PI3K/Akt or RhoA knockdown or inhibition. Additionally, Wnt5a in cooperation with CCL25 promoted MOLT4 cell mouse liver metastasis and stimulated RhoA activation. These results show that CCL25/CCR9 upregulates Wnt5a by promoting PKC expression and activation in MOLT4 cells. This in turn promotes cell migration and invasion via PI3K/Akt-RhoA signaling, enhancing cell polarization and pseudopodium formation. These findings indicate that the PI3K/Akt-RhoA pathway is likely responsible for Wnt5a-induced adult T-ALL cell migration and invasion.
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Movimiento Celular , Quimiocinas CC/metabolismo , Regulación Neoplásica de la Expresión Génica/fisiología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Transducción de Señal/fisiología , Proteína Wnt-5a/metabolismo , Animales , Línea Celular Tumoral , Xenoinjertos , Humanos , Ratones , Ratones SCID , Invasividad Neoplásica/patología , Metástasis de la NeoplasiaRESUMEN
Cancer has been a major public health problem that has threatened human life worldwide throughout history. The main causes that contribute to the poor prognosis of cancer are metastasis and recurrence. Cancer stem cells are a group of tumor cells that possess self-renewal and differentiation ability, which is a vital cause of cancer metastasis and recurrence. Long non-coding RNAs refer to a class of RNAs that are longer than 200 nt and have no potential to code proteins, some of which can be specifically expressed in different tissues and different tumors. Long non-coding RNAs have great biological significance in the occurrence and progression of cancers. However, how long non-coding RNAs interact with cancer stem cells and then affect cancer metastasis and recurrence is not yet clear. Therefore, this review aims to summarize recent studies that focus on how long non-coding RNAs impact tumor occurrence and progression by affecting cancer stem cell self-renewal and differentiation in liver cancer, prostate cancer, breast cancer, and glioma.