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1.
Oncol Lett ; 28(6): 554, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39355786

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive disease with the capability of metastasizing quickly. However, treatment options for patients with TNBC still remain limited. CDK4/6 inhibitors have been approved by the U.S. Food and Drug Administration and are administered for the treatment of hormone receptor-positive breast cancer subtypes, but not yet for TNBC. Although pre-clinical research is being conducted on their efficacy in treating TNBC, acquired resistance to CDK4/6 inhibitors is now a growing clinical problem. One of the identified resistance mechanisms is through the IL-6/STAT3 signaling pathway. In the present study, the CDK4/6 inhibitor, abemaciclib, was tested in combination with the IL-6 inhibitor, bazedoxifene, on human (SUM159 and MDA-MB-231) and murine (4T1) TNBC cell lines. Both abemaciclib and bazedoxifene monotherapies inhibited cell cycle progression and cell viability, migration and invasion, and induced apoptosis; however, the combination treatment exerted a greater effect than either monotherapy. These findings support the concept of CDK4/6 and IL-6 dual inhibition as a novel targeted therapy against TNBC.

2.
Front Med (Lausanne) ; 11: 1462649, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39399103

RESUMEN

Background: Recurrent spontaneous abortion (RSA) is a multifactorial disease, the exact causes of which are still unknown. Environmental, maternal, and genetic factors have been shown to contribute to this condition. The aim of this study was to investigate the presence of mutations in the ANXA4 gene in patients with RSA. Methods: Genomic DNA was extracted from 325 patients with RSA and 941 control women with a normal reproductive history for whole-exome sequencing (WES). The detected variants were annotated and filtered, and the pathogenicity of the variants was predicted through the SIFT online tool, functional enrichment analyses, Sanger sequencing validation, prediction of changes in protein structure, and evolutionary conservation analysis. Furthermore, plasmid construction, Western blotting, RT-qPCR, and cell migration, invasion and adhesion assays were used to detect the effects of ANXA4 mutations on protein function. Results: An ANXA4 mutation (p.G8D) in 1 of the 325 samples from patients with RSA (RSA-219) was identified through WES. This mutation was not detected in 941 controls or included in public databases. Evolutionary conservation analysis revealed that the amino acid residue affected by the mutation (p.G8D) was highly conserved among 13 vertebrate species, and the SIFT program and structural modeling analysis predicted that this mutation was harmful. Furthermore, functional assays revealed that this mutation could inhibit cell migration, invasion and adhesion. Conclusion: Our study suggests that an unreported novel ANXA4 mutation (p.G8D) plays an important role in the pathogenesis of RSA and may contribute to the genetic diagnosis of RSA.

3.
Bull Exp Biol Med ; 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39455498

RESUMEN

Serine-threonine kinase receptor-associated protein (STRAP) regulates cell proliferation and apoptosis by binding to many target proteins and plays an important regulatory role in tumor development. We studied the effects of STRAP on non-small cell lung cancer (NSCLC) in vivo and in vitro in order to elucidate possible mechanisms underlying the regulatory effects of this protein. The levels of STRAP in NSCLC tissues and cells were determined by quantitative reverse transcription PCR, immunohistochemical staining, and Western blotting. In in vitro experiments, A549 and HCC827 cells were transfected with small interfering RNA (siRNA) to knockdown STRAP (si-STRAP) or with negative control sequence; cell migration and invasion were detected by scratch and Transwell assays, respectively. The expression levels of X-linked inhibitor of apoptosis protein (XIAP), caspase-3, and caspase-9 were determined by Western blotting. In addition, we analyzed changes of tumor volume in a nude mouse NSCLC model. STRAP was highly expressed in NSCLC tissues and cells, but its expression was significantly suppressed in A549 and HCC827 cells transfected with si-STRAP. STRAP knockdown resulted in a significant inhibition of migration and invasion of A549 and HCC827 cells. It also significantly reduced the expression of XIAP and elevated expression of caspase-3 and caspase-9. In nude mice with tumor originated from transplanted A549 cells, inhibition of STRAP expression retarded the tumor growth. Overall, these findings indicate that STRAP is overexpressed in NSCLC, while knockdown of STRAP gene inhibits the growth of NSCLC.

4.
Biomolecules ; 14(10)2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39456164

RESUMEN

Gliomas represent the most common primary Central Nervous System (CNS) tumors, characterized by increased heterogeneity, dysregulated intracellular signaling, extremely invasive properties, and a dismal prognosis. They are generally resistant to existing therapies and only a few molecular targeting options are currently available. In search of signal transduction pathways with a potential impact in glioma growth and immunotherapy, the Slit guidance ligands (Slits) and their Roundabout (Robo) family of receptors have been revealed as key regulators of tumor cells and their microenvironment. Recent evidence indicates the implication of the Slit/Robo signaling pathway in inflammation, cell migration, angiogenesis, and immune cell infiltration of gliomas, suppressing or promoting the expression of pivotal proteins, such as cell adhesion molecules, matrix metalloproteinases, interleukins, angiogenic growth factors, and immune checkpoints. Herein, we discuss recent data on the significant implication of the Slit/Robo signaling pathway in glioma pathology along with the respective targeting options, including immunotherapy, monoclonal antibody therapy, and protein expression modifiers.


Asunto(s)
Glioma , Receptores Inmunológicos , Proteínas Roundabout , Transducción de Señal , Humanos , Glioma/metabolismo , Glioma/terapia , Glioma/patología , Glioma/genética , Receptores Inmunológicos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Inmunoterapia , Microambiente Tumoral , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética
5.
FASEB J ; 38(20): e70119, 2024 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-39441647

RESUMEN

Babesia spp. are obligate intracellular parasites that invade host cells to complete their asexual development and transmission. Here, we identified a transcription factor AP2-M (BXIN_0799) in Babesia sp. Xinjiang (Bxj), a member of the Apicomplexan AP2 family, which regulates gene expression related to red blood cell (RBC) invasion and cell cycle progression. Our genome-wide analysis of (Cut-Tag) data shows that AP2-M specifically recognized DNA motifs in the promoters of target genes. AP2-M target genes included other AP2 gene family members and epigenetic markers, which could modulate gene expression involved in RBC invasion, merozoite morphology, and cell cycle phases, as indicated by RNA sequencing, proteomics, and single-cell RNA sequencing (scRNA-seq) data from an ap2-m gene disrupted strain (AP2-M (-)). We conclude that AP2-M appeared to contribute to the process of red blood cell invasion, maintain merozoite morphology, and cell cycle progression through GS and MS phases.


Asunto(s)
Babesia , Proteínas Protozoarias , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/genética , Babesia/genética , Babesia/metabolismo , Factor de Transcripción AP-2/metabolismo , Factor de Transcripción AP-2/genética , Eritrocitos/parasitología , Eritrocitos/metabolismo , Reproducción Asexuada/genética , Animales , Ciclo Celular , Humanos , Regiones Promotoras Genéticas
6.
Biomed Pharmacother ; 180: 117579, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39442233

RESUMEN

BACKGROUND: Dilated cardiomyopathy (DCM) is characterized by enlarged, weakened heart ventricles due to chronic fibrosis. Dysfunctional senescent myofibroblasts and excessive citrullination have been implicated in fibrotic diseases. Peptidylarginine deiminases (PADs) are involved in the citrullination of ECM proteins. However, their role in regulating the cellular functions of cardiac myofibroblasts in DCM, is not well understood. This study aimed to evaluate the role of PADs in the cellular biology and fibrotic behavior of myofibroblasts in DCM. RESULTS: Aged cardiac myofibroblasts derived from dilated cardiomyopathy (DCM, N=5) and healthy (HCF, N=3) participants (35-60 years), were cultured in TGFB-conditioned medium and treated with an irreversible pan-PAD inhibitor BB-Cl-amidine. Our findings showed that, compared with HCFs, DCM myofibroblasts showed high expression of PAD-2, PAD-3, citrullinated proteins and ECM proteins (vimentin, fibronectin, actin, and b-Tubulin). BB-Cl-amidine-mediated PAD inhibition directly affected the cell biology of DCM myofibroblasts, as shown by the reduced migration and invasion of DCM myofibroblasts. It also augmented the apoptosis by activating caspase-3 and decreased senescence by regulating p-53. PAD inhibition did not affect the citrullination of vimentin or fibronectin; however, it decreased collagen 1 A expression. CONCLUSIONS: This study revealed that elevated PAD expression facilitates cellular processes mainly senescence, migration, and invasion. PAD inhibition resulted in the downregulation of these cellular functions, thereby reducing the fibrotic behavior of DCM myofibroblasts.

7.
Biosci Rep ; 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39474810

RESUMEN

Early-onset pre-eclampsia is believed to arise from defective placentation in the 1st trimester, leading to placental ischaemia/reperfusion (I/R) and oxidative stress. However, our current understanding of the effects of I/R and oxidative stress on trophoblast function is ambiguous in part due to studies exposing trophoblasts to hypoxia instead of I/R, and which report conflicting results. Here we present a model of simulated ischaemia/reperfusion (SI/R) to recapitulate the pathophysiological events of early-onset PE, by exposing 1st trimester cytotrophoblast HTR-8/SVneo cells to a simulated ischaemia buffer followed by reperfusion. We examined different ischaemia and reperfusion times and observed that 1h ischaemia and 24h reperfusion induced an increase in reactive oxygen species (ROS) production (p < 0.0001) and oxygen consumption rate (p < 0.01). SI/R-exposed trophoblast cells exhibited deficits in migration, proliferation and invasion (p < 0.01). While the deficits in migration and proliferation were rescued by antioxidants, suggesting a ROS-dependent mechanism, the loss of invasion was not affected by antioxidants, which suggests a divergent ROS-independent pathway. In line with this, we observed a decrease in MMP-9, the key regulatory enzyme necessary for trophoblast invasion (p < 0.01), which was similarly unaffected by antioxidants, and pharmacological inhibition of MMP-9 replicated the phenotype of deficient invasion (p < 0.01). Collectively, these data demonstrate that I/R impairs trophoblast migration and proliferation via a ROS-dependent mechanism, and invasion via a ROS-independent loss of MMP-9, disambiguating the role of oxidative stress and providing insights into the response of trophoblasts to I/R in the context of early-onset PE.

8.
Cells ; 13(19)2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39404389

RESUMEN

Mdmx (Mdm4) is established as an oncogene mainly through repression of the p53 tumour suppressor. On the other hand, anti-oncogenic functions for Mdmx have also been proposed, but the underlying regulatory pathways remain unknown. Investigations into the effect of inhibitors for the NEDD8 pathway in p53 activation, human cell morphology, and in cell motility during gastrulation in Xenopus embryos revealed an anti-invasive function of Mdmx. Through stabilisation and activation of the RhoA GTPase, Mdmx is required for the anti-invasive effects of NEDDylation inhibitors. Mechanistically, through its Zn finger domain, Mdmx preferentially interacts with the inactive GDP-form of RhoA. This protects RhoA from degradation and allows for RhoA targeting to the plasma membrane for its subsequent activation. The effect is transient, as prolonged NEDDylation inhibition targets Mdmx for degradation, which subsequently leads to RhoA destabilisation. Surprisingly, Mdmx degradation requires non-NEDDylated (inactive) Culin4A and the Mdm2 E3-ligase. This study reveals that Mdmx can control cell invasion through RhoA stabilisation/activation, which is potentially linked to the reported anti-oncogenic functions of Mdmx. As inhibitors of the NEDD8 pathway are in clinical trials, the status of Mdmx may be a critical determinant for the anti-tumour effects of these inhibitors.


Asunto(s)
Proteína NEDD8 , Proteína de Unión al GTP rhoA , Humanos , Proteína de Unión al GTP rhoA/metabolismo , Proteína NEDD8/metabolismo , Animales , Proteínas Proto-Oncogénicas/metabolismo , Transducción de Señal/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Pirimidinas/farmacología , Proteínas de Ciclo Celular/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Cullin/metabolismo , Invasividad Neoplásica , Gastrulación , Proteolisis/efectos de los fármacos , Ciclopentanos/farmacología , Ciclopentanos/metabolismo
9.
J Cancer Res Clin Oncol ; 150(10): 461, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39402299

RESUMEN

BACKGROUND: Hilar cholangiocarcinoma (HCCA) is a common type of cholangiocarcinoma (CHOL) that originates from the right and/or left hepatic duct near the biliary tract confluence. The objective of this study is to investigate the impact of miR-182-5p on the proliferation and invasion of HCCA cells and identify a potential target for HCCA treatment. METHODS: HCCA tissues were collected and HCCA cells were cultured. miR-182-5p and F-box and WD repeat domain containing 7 (FBXW7) were detected. After transfection of miR-182-5p inhibitor into HCCA cells, cell proliferation and invasion were detected by cell counting 8-kit and Transwell assay. FBXW7 expression was detected by Western blot. The targeted relationship between miR-182-5p and FBXW7 3'UTR was verified by dual-luciferase report assay. si-FBXW7 and miR-182-5p inhibitor were transfected into cells for combined experiments. HCCA cells with lowly-expressed miR-182-5p were injected into nude mice to establish the xenograft tumor model, and subsequent observations were made on tumor growth and gene expression changes. RESULTS: miR-182-5p exhibited high expression levels in both HCCA tissues and cell lines. Inhibiting miR-182-5p effectively suppressed the proliferation and migration of HCCA cells. miR-182-5p bounded to FBXW7 3 'UTR and inhibited FBWX7 expression. Suppressing FBXW7 expression partially reversed the inhibitory effect of miR-182-5p inhibitor on HCCA cell proliferation and invasion. Silencing miR-182-5p could inhibit the HCCA growth in vivo. CONCLUSION: miR-182-5p promoted the proliferation and invasion of HCCA cells by targeting and inhibiting FBXW7 expression.


Asunto(s)
Neoplasias de los Conductos Biliares , Proliferación Celular , Colangiocarcinoma , Proteína 7 que Contiene Repeticiones F-Box-WD , Ratones Desnudos , MicroARNs , Invasividad Neoplásica , MicroARNs/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Humanos , Proliferación Celular/genética , Animales , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Colangiocarcinoma/metabolismo , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/metabolismo , Ratones , Invasividad Neoplásica/genética , Línea Celular Tumoral , Masculino , Regulación Neoplásica de la Expresión Génica , Femenino , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto , Persona de Mediana Edad
10.
Technol Cancer Res Treat ; 23: 15330338241286283, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39327992

RESUMEN

INTRODUCTION: Colorectal cancer (CRC) is the world's third most frequent cancer, with a significant mortality rate due to late detection. There is a need to search for biomarkers that can detect colorectal cancer at an early stage. MicroRNAs (miRNAs) regulate several targets that function as oncogenes and/or tumor suppressor genes, so any change in microRNA expression level can predict abnormality. OBJECTIVE: The objective of the study was to evaluate the expression of miR-1290, and Suppressor of cancer cell invasion (SCAI) gene that may be used as biomarkers for early diagnosis of colorectal carcinoma. METHODOLOGY: This study included 50 subjects consisting of newly diagnosed colorectal carcinoma patients (n = 25), and healthy controls (n = 25). After RNA isolation and reverse transcription, the expression level of miR-1290 and SCAI gene in the tissues and plasma samples of CRC patients were analyzed using real time PCR and compared with healthy individuals as normal controls. The 2-ΔΔCt formula was used to compute the fold-change, while using miR-16 and GAPDH as reference genes for normalization. RESULTS: We found that miR-1290 is upregulated, whereas SCAI gene is downregulated in both plasma and tissue samples of CRC patients. For miR-1290, the sensitivity was 96% and specificity was 100%, and for SCAI, 100% sensitivity and 88% specificity was calculated by ROC analysis. CONCLUSION: The expression of miR-1290 and SCAI gene may be utilized as biomarkers for diagnosis of colorectal carcinoma.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Colorrectales , Regulación Neoplásica de la Expresión Génica , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/sangre , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Biomarcadores de Tumor/genética , Femenino , Masculino , Persona de Mediana Edad , Curva ROC , Anciano , Estudios de Casos y Controles , Adulto , Estadificación de Neoplasias
11.
Int J Mol Sci ; 25(18)2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39337713

RESUMEN

Glial-cell-line-derived neurotrophic factor (GDNF) is highly expressed and is involved in the malignant phenotype in glioblastomas (GBMs). However, uncovering its underlying mechanism for promoting GBM progression is still a challenging work. In this study, we found that serine protease inhibitor family E member 1 (SERPINE1) was a potential downstream gene of GDNF. Further experiments confirmed that SERPINE1 was highly expressed in GBM tissues and cells, and its levels of expression and secretion were enhanced by exogenous GDNF. SERPINE1 knockdown inhibited the migration and invasion of GBM cells promoted by GDNF. Mechanistically, GDNF increased SERPINE1 by promoting the phosphorylation of SMAD2/3. In vivo experiments demonstrated that GDNF facilitated GBM growth and the expressions of proteins related to migration and invasion via SERPINE1. Collectively, our findings revealed that GDNF upregulated SERPINE1 via the SMAD2/3-signaling pathway, thereby accelerating GBM cell migration and invasion. The present work presents a new mechanism of GDNF, supporting GBM development.


Asunto(s)
Movimiento Celular , Factor Neurotrófico Derivado de la Línea Celular Glial , Glioblastoma , Invasividad Neoplásica , Inhibidor 1 de Activador Plasminogénico , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/genética , Ratones Desnudos , Inhibidor 1 de Activador Plasminogénico/metabolismo , Inhibidor 1 de Activador Plasminogénico/genética , Proteína Smad2/metabolismo , Proteína Smad2/genética , Proteína smad3/metabolismo , Proteína smad3/genética
12.
Int J Mol Sci ; 25(18)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39337285

RESUMEN

Infection with Campylobacter jejuni is the major cause of human gastroenteritis in the United States and Europe, leading to debilitating autoimmune sequelae in many cases. While considerable progress has been made in detailing the infectious cycle of C. jejuni, a full understanding of the molecular mechanisms responsible for virulence remains to be elucidated. Here, we apply a novel approach by modulating protein expression on the pathogen's ribosomes by inactivating a highly conserved rRNA methyltransferase. Loss of the RsmA methyltransferase results in a more motile strain with greater adhesive and cell-invasive properties. These phenotypical effects correlate with enhanced expression of specific proteins related to flagellar formation and function, together with enzymes involved in cell wall/membrane and amino acid synthesis. Despite the enhancement of certain virulent traits, the null strain grows poorly on minimal media and is rapidly out-competed by the wild-type strain. Complementation with an active copy of the rsmA gene rescues most of the traits changed in the mutant. However, the complemented strain overexpresses rsmA and displays new flaws, including loss of the spiral cell shape, which is distinctive for C. jejuni. Proteins linked with altered virulence and morphology are identified here by mass spectrometry proteomic analyses of the strains.


Asunto(s)
Proteínas Bacterianas , Campylobacter jejuni , Metiltransferasas , Ribosomas , Campylobacter jejuni/patogenicidad , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Ribosomas/metabolismo , Ribosomas/genética , Virulencia/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Metiltransferasas/metabolismo , Metiltransferasas/genética , Metilación , Regulación Bacteriana de la Expresión Génica , Humanos , Infecciones por Campylobacter/microbiología , Proteómica/métodos
13.
Int J Biol Macromol ; 279(Pt 3): 135394, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39245093

RESUMEN

The onset and progression of colorectal cancer is intricately linked to a multitude of factors. Among these, immune cells present within the tumor microenvironment play a pivotal role, particularly natural killer (NK) cells, which are essential for mediating anti-tumor immunity. This study aims to elucidate the mechanism by which the VWA2 protein facilitates the invasion and migration of colorectal cancer cells through the inhibition of NK cell activation. Understanding this molecular mechanism is crucial for deciphering the underlying processes involved in colorectal cancer. To achieve the study's objectives, various methodologies were employed, including cell culture techniques, transgenic technology, and assessments of NK cell functionality. The "limma" bioinformatics tool was utilised to identify differentially expressed genes (DEGs) between samples of colon cancer or polyps and normal tissue through transcriptome sequencing. Subsequent Wien analysis was conducted to pinpoint overlapping genes of interest. The impact of VWA2 on both the invasion and migration of colorectal cancer cell lines was assessed through experiments designed for the overexpression and knockout of VWA2.In addition, flow cytometry was employed to evaluate the activation status of NK cells, enabling an analysis of how VWA2 modulates relevant signaling pathways. The findings revealed that overexpression of VWA2 led to a marked inhibition of NK cell activation, which corresponded with reduced cytotoxic activity against tumor cells. Further examination indicated that VWA2 significantly amplified the migration and invasion capabilities of colorectal cancer cells by upregulating immunosuppressive factors while simultaneously downregulating pro-inflammatory factors. Conversely, the reduction of VWA2 expression was shown to markedly enhance NK cell functionality and decrease the invasive potential of colorectal cancer cells. Thus, the evidence suggests that the VWA2 protein actively promotes the migration and invasion of colorectal cancer cells primarily by suppressing NK cell activation, highlighting its potential role as a significant contributor to tumor progression in colorectal cancer.


Asunto(s)
Movimiento Celular , Neoplasias Colorrectales , Regulación Neoplásica de la Expresión Génica , Células Asesinas Naturales , Invasividad Neoplásica , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/metabolismo , Movimiento Celular/genética , Línea Celular Tumoral , Activación de Linfocitos , Microambiente Tumoral/inmunología , Transducción de Señal
14.
Int J Mol Sci ; 25(17)2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39273173

RESUMEN

Escherichia coli O157:H7 (E. coli O157) is known for causing severe foodborne illnesses such as hemorrhagic colitis and hemolytic uremic syndrome. Although E. coli O157 is typically regarded as an extracellular pathogen and a weak biofilm producer, some E. coli O157 strains, including a clinical strain ATCC 43895, exhibit a notable ability to invade bovine crypt cells and other epithelial cells, as well as to form robust biofilm. This invasive strain persists in the bovine host significantly longer than non-invasive strains. Various surface-associated factors, including lipopolysaccharides (LPS), flagella, and other adhesins, likely contribute to this enhanced invasiveness and biofilm formation. In this study, we constructed a series of LPS-core deletion mutations (waaI, waaG, waaF, and waaC) in E. coli O157 ATCC 43895, resulting in stepwise truncations of the LPS. This approach enabled us to investigate the effects on the biosynthesis of key surface factors, such as flagella and curli, and the ability of this invasive strain to invade host cells. We confirmed the LPS structure and found that all LPS-core mutants failed to form biofilms, highlighting the crucial role of core oligosaccharides in biofilm formation. Additionally, the LPS inner-core mutants ΔwaaF and ΔwaaC lost the ability to produce flagella and curli. Furthermore, these inner-core mutants exhibited a dramatic reduction in adherence to and invasion of epithelial cells (MAC-T), showing an approximately 100-fold decrease in cell invasion compared with the outer-core mutants (waaI and waaG) and the wild type. These findings underscore the critical role of LPS-core truncation in impairing flagella and curli biosynthesis, thereby reducing the invasion capability of E. coli O157 ATCC 43895.


Asunto(s)
Biopelículas , Escherichia coli O157 , Flagelos , Lipopolisacáridos , Flagelos/metabolismo , Flagelos/genética , Lipopolisacáridos/biosíntesis , Escherichia coli O157/genética , Escherichia coli O157/metabolismo , Escherichia coli O157/fisiología , Biopelículas/crecimiento & desarrollo , Animales , Bovinos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Adhesión Bacteriana , Células Epiteliales/microbiología , Células Epiteliales/metabolismo
15.
Biochem Biophys Rep ; 39: 101808, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39238505

RESUMEN

The evolution of methicillin-resistant Staphylococcus aureus (MRSA) has required the development of new antimicrobial agents and new approaches to prevent and overcome drug resistance. AntiMicrobial Peptides (AMPs) represent promising alternatives due to their rapid bactericidal activity and their broad-spectrum of action against a wide range of microorganisms. The amphibian Temporins constitute a well-known family of AMPs with high antibacterial properties against both Gram-positive and Gram-negative bacteria. In this paper, we evaluated the in vivo effect of Temp-L on S. aureus performing morphological studies using Transmission Electron Microscopy (TEM) that revealed the occurrence of protrusions from the cell surface. The formation of vesicle-like structure was confirmed by Dynamic Light Scattering (DLS). The global effect of Temp-L on Staphylococcus aureus (S. aureus) was deeply investigated by differential proteomics leading to the identification of up-regulated proteins involved in the synthesis of the cell membrane and fatty acids, and down-regulated virulence factors. GC-MS analysis suggested a possible protective response mechanism implemented by the bacterium after treatment with Temp-L, as the synthesis of fatty acids was increased. Adhesion and invasion assays on eukaryotic cells confirmed a reduced virulence of S. aureus following treatment with Temp-L. These results suggested the targeting of virulence factors as novel strategy to replace traditional antimicrobial agents that can be used to treat infections, especially infections caused by the resistant pathogen S. aureus.

16.
Biology (Basel) ; 13(9)2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39336161

RESUMEN

Prostate cancer is the second most common neoplasia and fifth-leading cause of cancer death in men worldwide. Electromagnetic and magnetic fields have been classified as possible human carcinogens, but current understanding of molecular and cellular pathways involved is very limited. Effects due to extremely low magnetic/hypomagnetic fields (LMF) are furthermore poorly understood. Extracellular vesicles (EVs) are crucial mediators of cellular communication with multifaceted roles in cancer progression, including via transport and uptake of various protein and microRNA (miRNA) EV-cargoes. miRNAs regulate gene expression and are implicated in cancer-related processes such as proliferation, metastasis, and chemoresistance. This study investigated the effects of LMF exposure (20 nT) by magnetic shielding on the prostate cancer cell line PC3 compared to the prostate epithelial cell line PNT2 under short-term (4 h) conditions. We examined EV profiles following a 4 h LMF exposure alongside associated functional enrichment KEGG and GO pathways for the EV proteomes. The 4 h LMF exposure significantly reduced cellular EV release and modified PC3 EV cargoes to a more inflammatory and metastatic profile, with 16 Disease Pathways and 95 Human Phenotypes associated specifically with the LMF-treated PC3 EV proteomes. These included cancerous, metabolic, blood, skin, cardiac and skeletal Disease Pathways, as well as pain and developmental disorders. In the normal PNT2 cells, less EV protein cargo was observed following LMF exposure compared with cells not exposed to LMF, and fewer associated functional enrichment pathways were identified. This pointed to some differences in various cellular functions, ageing, defence responses, oxidative stress, and disease phenotypes, including respiratory, digestive, immune, and developmental pathways. Furthermore, we analysed alterations in matrix metalloproteinases (MMPs) and miRNAs linked to metastasis, as this is crucial in cancer aggressiveness. The 4 h LMF exposure caused a significant increase in MMP2 and MMP9, as well as in onco-miRs miR-155, miR-210, miR-21, but a significant reduction in tumour-suppressor miRs (miR-200c and miR-126) in the metastatic PC3 cells, compared with normal PNT2 cells. In addition, 4 h LMF exposure significantly induced cellular invasion of PC3 cells. Overall, our findings suggest that changes in magnetic field exposures modulate EV-mediated and miR-regulatory processes in PCa metastasis, providing a basis for exploring novel therapeutic strategies.

17.
J Biol Chem ; 300(9): 107672, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39128723

RESUMEN

The ubiquitin-proteasome system (UPS), which involves E3 ligases and deubiquitinates (DUBs), is critical for protein homeostasis. The epigenetic reader ZMYND8 (zinc finger MYND-type containing 8) has emerged as an oncoprotein, and its protein levels are elevated in various types of cancer, including breast cancer. However, the mechanism by which ZMYND8 protein levels are increased in cancer remains elusive. Although ZMYND8 has been reported to be regulated by the E3 ligase FBXW7, it is still unknown whether ZMYND8 could be modulated by DUBs. Here, we identified USP7 (ubiquitin carboxyl-terminal hydrolase 7) as a bona fide DUB for ZMYND8. Mechanically, USP7 directly binds to the PBP (PHD-BRD-PWWP) domain of ZMYND8 via its TRAF (tumor necrosis factor receptor-associated factor) domain and UBL (ubiquitin-like) domain and removes F-box and WD repeat domain containing 7 (FBXW7)-catalyzed poly-ubiquitin chains on lysine residue 1034 (K1034) within ZMYND8, thereby stabilizing ZMYND8 and stimulating the transcription of ZMYND8 target genes ZEB1 (zinc finger E-box binding homeobox 1) and VEGFA (Vascular Endothelial Growth Factor A). Consequently, USP7 enhances the capacity of breast cancer cells for migration and invasion through antagonizing FBXW7-mediated ZMYND8 degradation. Importantly, the protein levels of USP7 positively correlates with those of ZMYND8 in breast cancer tissues. These findings delineate an important layer of migration and invasion regulation by the USP7-ZMYND8 axis in breast cancer cells.


Asunto(s)
Neoplasias de la Mama , Movimiento Celular , Invasividad Neoplásica , Peptidasa Específica de Ubiquitina 7 , Ubiquitinación , Humanos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Peptidasa Específica de Ubiquitina 7/metabolismo , Peptidasa Específica de Ubiquitina 7/genética , Femenino , Línea Celular Tumoral , Epigénesis Genética , Células HEK293 , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Proteínas Supresoras de Tumor
18.
Infect Immun ; 92(10): e0026624, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39133016

RESUMEN

Salmonella enterica serovar Typhimurium (S. Typhimurium) infection triggers an inflammatory response that changes the concentration of metabolites in the gut impacting the luminal environment. Some of these environmental adjustments are conducive to S. Typhimurium growth, such as the increased concentrations of nitrate and tetrathionate or the reduced levels of Clostridia-produced butyrate. We recently demonstrated that S. Typhimurium can form biofilms within the host environment and respond to nitrate as a signaling molecule, enabling it to transition between sessile and planktonic states. To investigate whether S. Typhimurium utilizes additional metabolites to regulate its behavior, our study delved into the impact of inflammatory metabolites on biofilm formation. The results revealed that lactate, the most prevalent metabolite in the inflammatory environment, impedes biofilm development by reducing intracellular c-di-GMP levels, suppressing the expression of curli and cellulose, and increasing the expression of flagellar genes. A transcriptomic analysis determined that the expression of the de novo purine pathway increases during high lactate conditions, and a transposon mutagenesis genetic screen identified that PurA and PurG, in particular, play a significant role in the inhibition of curli expression and biofilm formation. Lactate also increases the transcription of the type III secretion system genes involved in tissue invasion. Finally, we show that the pyruvate-modulated two-component system BtsSR is activated in the presence of high lactate, which suggests that lactate-derived pyruvate activates BtsSR system after being exported from the cytosol. All these findings propose that lactate is an important inflammatory metabolite used by S. Typhimurium to transition from a biofilm to a motile state and fine-tune its virulence.IMPORTANCEWhen colonizing the gut, Salmonella enterica serovar Typhimurium (S. Typhimurium) adopts a dynamic lifestyle that alternates between a virulent planktonic state and a multicellular biofilm state. The coexistence of biofilm formers and planktonic S. Typhimurium in the gut suggests the presence of regulatory mechanisms that control planktonic-to-sessile transition. The signals triggering the transition of S. Typhimurium between these two lifestyles are not fully explored. In this work, we demonstrated that in the presence of lactate, the most dominant host-derived metabolite in the inflamed gut, there is a reduction of c-di-GMP in S. Typhimurium, which subsequently inhibits biofilm formation and induces the expression of its invasion machinery, motility genes, and de novo purine metabolic pathway genes. Furthermore, high levels of lactate activate the BtsSR two-component system. Collectively, this work presents new insights toward the comprehension of host metabolism and gut microenvironment roles in the regulation of S. Typhimurium biology during infection.


Asunto(s)
Biopelículas , Regulación Bacteriana de la Expresión Génica , Ácido Láctico , Purinas , Salmonella typhimurium , Biopelículas/crecimiento & desarrollo , Salmonella typhimurium/metabolismo , Salmonella typhimurium/fisiología , Salmonella typhimurium/genética , Ácido Láctico/metabolismo , Purinas/metabolismo , Ratones , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Animales , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/metabolismo , GMP Cíclico/metabolismo , GMP Cíclico/análogos & derivados , Virulencia
19.
Cancer Biomark ; 40(3-4): 241-250, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39213051

RESUMEN

Transforming growth factor-ß (TGF-ß) is a multifunctional cytokine that plays a vital role in regulating cell growth, differentiation and survival in various tissues. It participates in a variety of cellular processes, including cell apoptosis, cell migration and evasion, and plays a paradoxical role in tumor genesis and development. In the early stage of tumor, TGF-ß inhibits the occurrence of tumor by inhibiting cell proliferation and regulating cell apoptosis. In the advanced stage of tumor, TGF-ß promotes tumor development and affects prognosis by promoting cell survival and proliferation, cell migration and invasion, participates in immune escape, etc. In this article, we will review the paradoxical role of TGF-ß on the occurrence and development of oral squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Boca , Factor de Crecimiento Transformador beta , Humanos , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Transducción de Señal , Proliferación Celular , Apoptosis , Animales , Pronóstico
20.
Postepy Dermatol Alergol ; 41(3): 284-291, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39027690

RESUMEN

Introduction: Malignant melanoma (MM) is a highly aggressive skin tumour. Aim: To investigate whether miR-22 is involved in the proliferation, invasion, and migration of melanoma cells (MCs) by negatively regulating NOD-like receptor protein 3 (NLRP3) gene. Material and methods: Human MCs (WM239a) and human epidermal melanocytes (HEM) were used as study material. The expression levels of miR-22 and NLRP3 were detected by qRT-PCR. The expression of NLRP3 protein was determined by Western blot (WB) analysis. The effects of miR-22 and NLRP3 on the proliferation, invasion, and migration of MCs were evaluated by cell counting kit-8 (CCK-8), Transwell cell invasion assay, and scratch assay. Results: The expression of miR-22 was clearly lower in WM239a than in HEM. Up-regulation of miR-22 expression in WM239a clearly raised the expression of miR-22, Caspase-1, and E-cadherin and the apoptotic rate of WM239a; however, the levels of interleukin-1ß (IL-1ß) and NLRP3, cell proliferation activity, invasion and migration ability were clearly decreased. The negative regulation of NLRP3 by miR-22 may play a major role in activities of MM. Conclusions: Further studies will help to reveal the molecular details of this regulatory mechanism and provide new therapeutic strategies.

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