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1.
Heliyon ; 10(11): e31487, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38828323

RESUMO

Background: Cervical cancer is one of the most common malignancies in women worldwide. As a RING type ubiquitin ligase, SIAH2 has been reported to promote the progression of a variety of tumors by interacting with and targeting multiple chaperones and substrates. The aim of this study was to further identify the role and the related molecular mechanisms involved of SIAH2 in cervical carcinogenesis. Methods and results: Cellular assays in vitro showed that knockdown of SIAH2 inhibited the proliferation, migration and invasion of human cervical cancer cells C33A and SiHa, induced apoptosis, and increased the sensitivity to cisplatin treatment. Knockdown of SIAH2 also inhibited the epithelial-mesenchymal transition and activation of the Akt/mTOR signaling pathway in cervical cancer cells, which were detected by Western blot. Mechanistically, SIAH2, as a ubiquitin ligase, induced the ubiquitination degradation of GSK3ß degradation by using coIP. The results of complementation experiments further demonstrated that GSK3ß overexpression rescued the increase of cell proliferation and invasion caused by SIAH2 overexpression. Specific expression of SIAH2 appeared in precancerous and cervical cancer tissues compared to inflammatory cervical lesions tissues using immunohistochemical staining. The more SIAH2 was expressed as the degree of cancer progressed. SIAH2 was significantly highly expressed in cervical cancer tissues (44/55, 80 %) compared with precancerous tissues (18/69, 26.1 %). Moreover, the expression level of SIAH2 in cervical cancer tissues was significantly correlated with the degree of cancer differentiation, and cervical cancer tissues with higher SIAH2 expression levels were less differentiated. Conclusion: Targeting SIAH2 may be beneficial to the treatment of cervical cancer.

2.
Lipids Health Dis ; 23(1): 194, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909243

RESUMO

BACKGROUND: Lipid droplet (LD)-laden microglia is a key pathological hallmark of multiple sclerosis. The recent discovery of this novel microglial subtype, lipid-droplet-accumulating microglia (LDAM), is notable for increased inflammatory factor secretion and diminished phagocytic capability. Lipophagy, the autophagy-mediated selective degradation of LDs, plays a critical role in this context. This study investigated the involvement of microRNAs (miRNAs) in lipophagy during demyelinating diseases, assessed their capacity to modulate LDAM subtypes, and elucidated the potential underlying mechanisms involved. METHODS: C57BL/6 mice were used for in vivo experiments. Two weeks post demyelination induction at cervical level 4 (C4), histological assessments and confocal imaging were performed to examine LD accumulation in microglia within the lesion site. Autophagic changes were observed using transmission electron microscopy. miRNA and mRNA multi-omics analyses identified differentially expressed miRNAs and mRNAs under demyelinating conditions and the related autophagy target genes. The role of miR-223 in lipophagy under these conditions was specifically explored. In vitro studies, including miR-223 upregulation in BV2 cells via lentiviral infection, validated the bioinformatics findings. Immunofluorescence staining was used to measure LD accumulation, autophagy levels, target gene expression, and inflammatory mediator levels to elucidate the mechanisms of action of miR-223 in LDAM. RESULTS: Oil Red O staining and confocal imaging revealed substantial LD accumulation in the demyelinated spinal cord. Transmission electron microscopy revealed increased numbers of autophagic vacuoles at the injury site. Multi-omics analysis revealed miR-223 as a crucial regulatory gene in lipophagy during demyelination. It was identified that cathepsin B (CTSB) targets miR-223 in autophagy to integrate miRNA, mRNA, and autophagy gene databases. In vitro, miR-223 upregulation suppressed CTSB expression in BV2 cells, augmented autophagy, alleviated LD accumulation, and decreased the expression of the inflammatory mediator IL-1ß. CONCLUSION: These findings indicate that miR-223 plays a pivotal role in lipophagy under demyelinating conditions. By inhibiting CTSB, miR-223 promotes selective LD degradation, thereby reducing the lipid burden and inflammatory phenotype in LDAM. This study broadens the understanding of the molecular mechanisms of lipophagy and proposes lipophagy induction as a potential therapeutic approach to mitigate inflammatory responses in demyelinating diseases.


Assuntos
Autofagia , Catepsina B , Doenças Desmielinizantes , Gotículas Lipídicas , Lisofosfatidilcolinas , Camundongos Endogâmicos C57BL , MicroRNAs , Microglia , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Microglia/metabolismo , Microglia/patologia , Camundongos , Gotículas Lipídicas/metabolismo , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/patologia , Catepsina B/metabolismo , Catepsina B/genética , Lisofosfatidilcolinas/metabolismo , Modelos Animais de Doenças , Masculino , Regulação da Expressão Gênica , Linhagem Celular
3.
J Dig Dis ; 25(4): 238-247, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38779802

RESUMO

OBJECTIVES: As a serious complication of moderately severe acute pancreatitis (MSAP) and severe acute pancreatitis (SAP), infected pancreatic necrosis (IPN) can lead to a prolonged course of interventional therapy. Most predictive models designed to identify such patients are complex or lack validation. The aim of this study was to develop a predictive model for the early detection of IPN in MSAP and SAP. METHODS: A total of 594 patients with MSAP or SAP were included in the study. To reduce dimensionality, least absolute shrinkage and selection operator regression analysis was used to screen potential predictive variables, a nomogram was then constructed using logistic regression analysis. The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the discrimination, accuracy, and clinical efficacy of the model. External data were also obtained to further validate the constructed model. RESULTS: There were 476, 118, and 82 patients in the training, internal validation, and external validation cohorts, respectively. Platelet count, hematocrit, albumin/globulin, severity of acute pancreatitis, and modified computed tomography severity index score were independent factors for predicting IPN in MSAP and SAP. The area under the ROC curves were 0.923, 0.940, and 0.817, respectively, in the three groups. There was a good consistency between the actual probabilities and the predicted probabilities. DCA revealed excellent clinical utility. CONCLUSION: The constructed nomogram is a simple and feasible model that has good clinical predictive value and efficacy in clinical decision-making for IPN in MSAP and SAP.


Assuntos
Nomogramas , Pancreatite Necrosante Aguda , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Pancreatite Necrosante Aguda/complicações , Pancreatite Necrosante Aguda/diagnóstico , Adulto , Curva ROC , Idoso , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X , Estudos Retrospectivos , Pancreatite/diagnóstico , Pancreatite/complicações
4.
Front Neurosci ; 18: 1360935, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38686327

RESUMO

Objective: According to the World Alzheimer's Disease Report in 2015,there were 9.9 million new cases of dementia in the world every year. At present, the number of patients suffering from dementia in China has exceeded 8 million, and it may exceed 26 million by 2040.Mild cognitive impairment (MCI) refers to the pathological state of pre-dementia with the manifestation of the progressive decline of memory or other cognitive functions but without decline of activities of daily life. It is particularly important to prevent or prolong the development of MCI into dementia. Research showing effects of rhythmic auditory stimulation based-movement training(RASMT) interventions on cognitive function is also emerging. Therefore, the present meta-analysis briefly summarize findings regarding the impacts of RASMT programs on cognitive impairment. Methods: Data from Pubmed, Embase, and Cochrane Library were utilized. The impact of RASMT on cognitive functions was evaluated using indicators such as overall cognitive status, memory, attention, and executive functions. The REVMAN5.3 software was employed to analyze bias risks integrated into the study and the meta-analysis results for each indicator. Results: A total of 1,596 studies were retrieved, of which 1,385 non-randomized controlled studies and 48 repetitive studies were excluded. After reviewing titles and abstracts of the remaining 163 articles, 133 irrelevant studies were excluded, 30 studies were downloaded and read the full text. Among 30 articles, 18 articles that did not meet the inclusion criteria were excluded, the other 12 studies were included in this meta-analysis. Utilizing the Cochrane Collaborative Network Bias Risk Assessment Scale, it was found that 11 studies explained the method of random sequence generation, nine studies did not describe allocation concealment, four were single-blinded to all researchers, and eight reported single-blinding in the evaluation of experimental results. In the meta-analysis, the main outcomes showed statistically significant differences in overall cognitive status [MD = 1.19, 95%CI (0.09, 2.29), (p < 0.05)], attention [MD = -1.86, 95%CI (-3.53, -0.19), (p < 0.05)], memory [MD = 0.71, 95%CI (0.33, 1.09), (p < 0.01)], and executive function [MD = -0.23, 95% CI (-0.44, -0.02), (p < 0.05)]. Secondary outcomes indicated no statistically significant differences in verbal fluency [MD = -0.51, 95%CI (-1.30, 0.27), (p = 0.20)], while depression [MD = -0.29, 95% CI (-0.42, -0.16), (p < 0.01)] and anxiety [MD = 0.19, 95% CI (0.06, 0.32), (p < 0.01)] exhibited statistically significant differences. The GRADEpro GDT online tool assessed the quality of evidence for the outcome measures, revealing one low-quality outcome, two moderate-quality outcomes, and one high-quality outcome in this review. Conclusion: This study shows that RASMT can improve the general cognitive status, memory, attention and executive function of patients with cognitive impairment. The quality of evidence revealed that MMSE was low, attention and memory were moderate, and executive function was high. The RAMST program (type of exercise: play percussion instruments; time of exercise: 30-60 min; frequency of exercise: 2-3 times/week; duration of exercise: more than 12 weeks) was proved to be more effective in improving cognitive function. However, the sample size is relatively insufficient, the future needs further study. Systematic review registration: PROSPERO, identifier: CRD42023483561.

5.
Wiley Interdiscip Rev RNA ; 15(2): e1845, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605485

RESUMO

For a long time, it was believed that new genes arise only from modifications of preexisting genes, but the discovery of de novo protein-coding genes that originated from noncoding DNA regions demonstrates the existence of a "motherless" origination process for new genes. However, the features, distributions, expression profiles, and origin modes of these genes in humans seem to support the notion that their origin is not a purely "motherless" process; rather, these genes arise preferentially from genomic regions encoding preexisting precursors with gene-like features. In such a case, the gene loci are typically not brand new. In this short review, we will summarize the definition and features of human de novo genes and clarify their process of origination from ancestral non-coding genomic regions. In addition, we define the favored precursors, or "hopeful monsters," for the origin of de novo genes and present a discussion of the functional significance of these young genes in brain development and tumorigenesis in humans. This article is categorized under: RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution.


Assuntos
Evolução Molecular , RNA , Humanos
6.
Genome Biol ; 25(1): 102, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641822

RESUMO

BACKGROUND: Splicing factors are vital for the regulation of RNA splicing, but some have also been implicated in regulating transcription. The underlying molecular mechanisms of their involvement in transcriptional processes remain poorly understood. RESULTS: Here, we describe a direct role of splicing factor RBM22 in coordinating multiple steps of RNA Polymerase II (RNAPII) transcription in human cells. The RBM22 protein widely occupies the RNAPII-transcribed gene locus in the nucleus. Loss of RBM22 promotes RNAPII pause release, reduces elongation velocity, and provokes transcriptional readthrough genome-wide, coupled with production of transcripts containing sequences from downstream of the gene. RBM22 preferentially binds to the hyperphosphorylated, transcriptionally engaged RNAPII and coordinates its dynamics by regulating the homeostasis of the 7SK-P-TEFb complex and the association between RNAPII and SPT5 at the chromatin level. CONCLUSIONS: Our results uncover the multifaceted role of RBM22 in orchestrating the transcriptional program of RNAPII and provide evidence implicating a splicing factor in both RNAPII elongation kinetics and termination control.


Assuntos
Fator B de Elongação Transcricional Positiva , RNA Polimerase II , Humanos , Cromatina , Fator B de Elongação Transcricional Positiva/genética , Fator B de Elongação Transcricional Positiva/metabolismo , RNA Polimerase II/metabolismo , Splicing de RNA , Fatores de Processamento de RNA/genética , Transcrição Gênica , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismo
7.
Neurospine ; 21(1): 223-230, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38317553

RESUMO

OBJECTIVE: The effect on fat infiltration (FI) of paraspinal muscles in degenerative lumbar spinal diseases has been demonstrated except for spinopelvic parameters. The present study is to identify the effect of spinopelvic parameters on FI of paraspinal muscle (PSM) and psoas major muscle (PMM) in patients with degenerative lumbar spondylolisthesis. METHODS: A single-center, retrospective cross-sectional study of 160 patients with degenerative lumbar spondylolisthesis (DLS) and lumbar stenosis (LSS) who had lateral full-spine x-ray and lumbar spine magnetic resonance imaging was conducted. PSM and PMM FIs were defined as the ratio of fat to its muscle cross-sectional area. The FIs were compared among patients with different pelvic tilt (PT) and pelvic incidence (PI), respectively. RESULTS: The PSM FI correlated significantly with pelvic parameters in DLS patients, but not in LSS patients. The PSM FI in pelvic retroversion (PT > 25°) was 0.54 ± 0.13, which was significantly higher in DLS patients than in normal pelvis (0.41 ± 0.14) and pelvic anteversion (PT < 5°) (0.34 ± 0.12). The PSM FI of DLS patients with large PI ( > 60°) was 0.50 ± 0.13, which was higher than those with small ( < 45°) and normal PI (0.37 ± 0.11 and 0.36 ± 0.13). However, the PSM FI of LSS patients didn't change significantly with PT or PI. Moreover, the PMM FI was about 0.10-0.15, which was significantly lower than the PSM FI, and changed with PT and PI in a similar way of PSM FI with much less in magnitude. CONCLUSION: FI of the PSMs increased with greater pelvic retroversion or larger pelvic incidence in DLS patients, but not in LSS patients.

8.
Int J Ophthalmol ; 17(1): 119-125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38239936

RESUMO

AIM: To investigate the difference of medial rectus (MR) and lateral rectus (LR) between acute acquired concomitant esotropia (AACE) and the healthy controls (HCs) detected by magnetic resonance imaging (MRI). METHODS: A case-control study. Eighteen subjects with AACE and eighteen HCs were enrolled. MRI scanning data were conducted in target-controlled central gaze with a 3-Tesla magnetic resonance scanner. Extraocular muscles (EOMs) were scanned in contiguous image planes 2-mm thick spanning the EOM origins to the globe equator. To form posterior partial volumes (PPVs), the LR and MR cross-sections in the image planes 8, 10, 12, and 14 mm posterior to the globe were summed and multiplied by the 2-mm slice thickness. The data were classified according to the right eye, left eye, dominant eye, and non-dominant eye, and the differences in mean cross-sectional area, maximum cross-sectional area, and PPVs of the MR and LR muscle in the AACE group and HCs group were compared under the above classifications respectively. RESULTS: There were no significant differences between the two groups of demographic characteristics. The mean cross-sectional area of the LR muscle was significantly greater in the AACE group than that in the HCs group in the non-dominant eyes (P=0.028). The maximum cross-sectional area of the LR muscle both in the dominant and non-dominant eye of the AACE group was significantly greater than the HCs group (P=0.009, P=0.016). For the dominant eye, the PPVs of the LR muscle were significantly greater in the AACE than that in the HCs group (P=0.013), but not in the MR muscle (P=0.698). CONCLUSION: The size and volume of muscles dominant eyes of AACE subjects change significantly to overcome binocular diplopia. The LR muscle become larger to compensate for the enhanced convergence in the AACE.

9.
Elife ; 122023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37847146

RESUMO

The landscape of extrachromosomal circular DNA (eccDNA) during mammalian spermatogenesis, as well as the biogenesis mechanism, remains to be explored. Here, we revealed widespread eccDNA formation in human sperms and mouse spermatogenesis. We noted that germline eccDNAs are derived from oligonucleosomal DNA fragmentation in cells likely undergoing cell death, providing a potential new way for quality assessment of human sperms. Interestingly, small-sized eccDNAs are associated with euchromatin, while large-sized ones are preferentially generated from heterochromatin. By comparing sperm eccDNAs with meiotic recombination hotspots and structural variations, we found that they are barely associated with de novo germline deletions. We further developed a bioinformatics pipeline to achieve nucleotide-resolution eccDNA detection even with the presence of microhomologous sequences that interfere with precise breakpoint identification. Empowered by our method, we provided strong evidence to show that microhomology-mediated end joining is the major eccDNA biogenesis mechanism. Together, our results shed light on eccDNA biogenesis mechanism in mammalian germline cells.


Assuntos
DNA Circular , Sêmen , Masculino , Animais , Humanos , Camundongos , DNA Circular/genética , Cromossomos , Espermatogênese/genética , Mamíferos/genética
10.
Nucleic Acids Res ; 51(14): 7357-7375, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37378420

RESUMO

DNA-RNA hybrids play various roles in many physiological progresses, but how this chromatin structure is dynamically regulated during spermatogenesis remains largely unknown. Here, we show that germ cell-specific knockout of Rnaseh1, a specialized enzyme that degrades the RNA within DNA-RNA hybrids, impairs spermatogenesis and causes male infertility. Notably, Rnaseh1 knockout results in incomplete DNA repair and meiotic prophase I arrest. These defects arise from the altered RAD51 and DMC1 recruitment in zygotene spermatocytes. Furthermore, single-molecule experiments show that RNase H1 promotes recombinase recruitment to DNA by degrading RNA within DNA-RNA hybrids and allows nucleoprotein filaments formation. Overall, we uncover a function of RNase H1 in meiotic recombination, during which it processes DNA-RNA hybrids and facilitates recombinase recruitment.


Assuntos
Meiose , Ribonuclease H , Humanos , Masculino , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , DNA/genética , DNA/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Recombinases/genética , Espermatócitos/metabolismo , Ribonuclease H/metabolismo
11.
J Mol Biol ; 435(14): 168142, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356907

RESUMO

Although nascent RNA profiling data are widely used in transcriptional regulation studies, the development and standardization of data processing pipeline lags far behind RNA-seq. We are filling this gap by establishing the nASAP web server (https://grobase.top/nasap/) to provide practical quality evaluation and comprehensive analysis of nascent RNA datasets. In nASAP, four customized analysis modules are provided, including i) quality assessment, which summarizes the sequencing statistics, mapping ratio, and evaluates RNA integrity and mRNA contamination; ii) quantification analysis for mRNAs, lncRNAs and eRNAs; iii) pausing analysis across the whole genome based on sequencing reads distribution; and iv) network analysis to better understand the gene regulatory mechanism by obtaining annotated enhancer-promoter interactomes. The nASAP is user-friendly and outperforms the existing pipeline for quality control of nascent RNA profiling data. We anticipate that nASAP, which eases both basic and advanced analysis of nascent RNA data, will be extremely useful in various fields.


Assuntos
Perfilação da Expressão Gênica , RNA Mensageiro , Software , Análise de Dados , Regulação da Expressão Gênica , RNA Mensageiro/genética , Análise de Sequência de RNA
12.
J Dig Dis ; 24(2): 70-84, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37220999

RESUMO

With the development and generalization of endoscopic technology and screening, clinical application of magnetically controlled capsule gastroscopy (MCCG) has been increasing. In recent years, various types of MCCG are used globally. Therefore, establishing relevant guidelines on MCCG is of great significance. The current guidelines containing 23 statements were established based on clinical evidence and expert opinions, mainly focus on aspects including definition and diagnostic accuracy, application population, technical optimization, inspection process, and quality control of MCCG. The level of evidence and strength of recommendations were evaluated. The guidelines are expected to guide the standardized application and scientific innovation of MCCG for the reference of clinicians.


Assuntos
Gastroscopia , Humanos , Gastroscopia/métodos , Magnetismo
13.
Cell Biosci ; 13(1): 82, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170281

RESUMO

BACKGROUND: Meiotic recombination is initiated by Spo11-dependent programmed DNA double-strand breaks (DSBs) that are preferentially concentrated within genomic regions called hotspots; however, the factor(s) that specify the positions of meiotic DSB hotspots remain unclear. RESULTS: Here, we examined the frequency and distribution of R-loops, a type of functional chromatin structure comprising single-stranded DNA and a DNA:RNA hybrid, during budding yeast meiosis and found that the R-loops were changed dramatically throughout meiosis. We detected the formation of multiple de novo R-loops in the pachytene stage and found that these R-loops were associated with meiotic recombination during yeast meiosis. We show that transcription-replication head-on collisions could promote R-loop formation during meiotic DNA replication, and these R-loops are associated with Spo11. Furthermore, meiotic recombination hotspots can be eliminated by reversing the direction of transcription or replication, and reversing both of these directions can reconstitute the hotspots. CONCLUSIONS: Our study reveals that R-loops may play dual roles in meiotic recombination. In addition to participation in meiotic DSB processing, some meiotic DSB hotspots may be originated from the transcription-replication head-on collisions during meiotic DNA replication.

14.
Ultraschall Med ; 44(4): 389-394, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37072032

RESUMO

PURPOSE: This study aims to investigate the effects of point-of-care ultrasound (PoCUS) on length of stay (LOS) and mortality in hemodynamically stable patients with chest pain/dyspnea. MATERIALS AND METHODS: The prospective study was conducted from June 2020 to May 2021. A convenience sample of adult non-traumatic patients with chest pain/dyspnea was included and evaluated by PoCUS. The primary outcome was the relationship between the door-to-PoCUS time and LOS/mortality categorized by the ST-segment elevation (STE) and non-STE on the initial electrocardiogram. The diagnostic accuracy of PoCUS was computed, compared to the final diagnosis. RESULTS: A total of 465 patients were included. 3 of 18 patients with STE had unexpected cardiac tamponade and 1 had myocarditis with pulmonary edema. PoCUS had a minimal effect on LOS and mortality in patients with STE. In the non-STE group, the shorter door-to-PoCUS time was associated with a shorter LOS (coefficient, 1.26±0.47, p=0.008). After categorizing the timing of PoCUS as 30, 60, 90, and 120 minutes, PoCUS had a positive effect, especially when performed within 90 minutes of arrival, on LOS of less than 360 minutes (OR, 2.42, 95% CI, 1.61-3.64) and patient survival (OR, 3.32, 95% CI, 1.14-9.71). The overall diagnostic performance of PoCUS was 96.6% (95% CI, 94.9-98.2%), but lower efficacy occurred in pulmonary embolism and myocardial infarction. CONCLUSION: The use of PoCUS was associated with a shorter LOS and less mortality in patients with non-STE, especially when performed within 90 minutes of arrival. Although the effect on patients with STE was minimal, PoCUS played a role in discovering unexpected diagnoses.


Assuntos
Dor no Peito , Sistemas Automatizados de Assistência Junto ao Leito , Adulto , Humanos , Tempo de Internação , Estudos Prospectivos , Dor no Peito/diagnóstico por imagem , Ultrassonografia , Dispneia , Serviço Hospitalar de Emergência
15.
J Am Chem Soc ; 145(16): 9334-9342, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37068218

RESUMO

Triple-negative breast cancer (TNBC) is highly aggressive with a poor clinical prognosis and no targeted therapy. The c-Myc protein is a master transcription factor and a potential therapeutic target for TNBC. In this study, we develop a PROTAC (PROteolysis TArgeting Chimera) based on TNA (threose nucleic acid) and DNA that effectively targets and degrades c-Myc. The TNA aptamer is selected in vitro to bind the c-Myc/Max heterodimer and appended to the E-box DNA sequence to create a high-affinity, biologically stable bivalent binder. The TNA-E box-pomalidomide (TEP) conjugate specifically degrades endogenous c-Myc/Max, inhibits TNBC cell proliferation, and sensitizes TNBC cells to the cyclin-dependent kinase inhibitor palbociclib in vitro. In a mouse TNBC model, combination therapy with TEP and palbociclib potently suppresses tumor growth. This study offers a promising nucleic acid-based PROTAC modality for both chemical biology studies and therapeutic interventions of TNBC.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Fatores de Transcrição , Neoplasias de Mama Triplo Negativas/patologia , Genes myc
17.
Nat Ecol Evol ; 7(2): 264-278, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36593289

RESUMO

Human de novo genes can originate from neutral long non-coding RNA (lncRNA) loci and are evolutionarily significant in general, yet how and why this all-or-nothing transition to functionality happens remains unclear. Here, in 74 human/hominoid-specific de novo genes, we identified distinctive U1 elements and RNA splice-related sequences accounting for RNA nuclear export, differentiating mRNAs from lncRNAs, and driving the origin of de novo genes from lncRNA loci. The polymorphic sites facilitating the lncRNA-mRNA conversion through regulating nuclear export are selectively constrained, maintaining a boundary that differentiates mRNAs from lncRNAs. The functional new genes actively passing through it thus showed a mode of pre-adaptive origin, in that they acquire functions along with the achievement of their coding potential. As a proof of concept, we verified the regulations of splicing and U1 recognition on the nuclear export efficiency of one of these genes, the ENSG00000205704, in human neural progenitor cells. Notably, knock-out or over-expression of this gene in human embryonic stem cells accelerates or delays the neuronal maturation of cortical organoids, respectively. The transgenic mice with ectopically expressed ENSG00000205704 showed enlarged brains with cortical expansion. We thus demonstrate the key roles of nuclear export in de novo gene origin. These newly originated genes should reflect the novel uniqueness of human brain development.


Assuntos
RNA Longo não Codificante , Camundongos , Animais , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Splicing de RNA , RNA Mensageiro/genética , Encéfalo/metabolismo
18.
Spine J ; 23(1): 64-71, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36202206

RESUMO

BACKGROUND CONTEXT: It is commonly believed that decreased bone quality would lead to endplate degeneration and arthritic changes in the facet joints, and thus accelerated disc degeneration (DD). However, some more detailed studies of vertebral bone structure have found that bone mineral density (BMD) in the vertebral body is increased rather than decreased in moderate or greater disc degeneration. The relationship between BMD and DD still needs further study. MRI-based vertebral bone quality scores have been shown to be effective in reflecting BMD, rendering a new way to evaluate the changes of vertebral body bone with DD using MRI alone. PURPOSE: To evaluate MRI-based vertebral bone quality and Pfirrmann grades in patients with lumbar spinal stenosis or disc herniation, and to identify if DD is associated with denser bone around the endplate. STUDY DESIGN/SETTING: A single-center, retrospective cohort study. PATIENT SAMPLE: A total of 130 patients with lumbar disc herniation and lumbar spinal stenosis from January 2019 to November 2020 who had a complete dual-energy X-ray absorptiometry scan and noncontrast lumbosacral spine MRI data. OUTCOME MEASURES: The vertebral bone quality score (VBQ) and sub-endplate bone quality score (EBQ) was calculated as a ratio of the signal intensity of the vertebral bodies and sub-endplate regions to the signal intensity of the cerebrospinal fluid at L3 on the mid-sagittal T1-weighted MRI images, respectively. The Pfirrmann grades of the lumbar discs were assessed as well. METHODS: The age, gender, body mass index, and T-score of the lumbar spine of the patients were collected. The degeneration grades of the lumbar discs were evaluated according to the Pfirrmann classification. VBQ and EBQ were measured through T1-weighted lumbar MRI. The VBQ and EBQ scores were compared between cranial and caudal sides. The correlation between MRI-based bone quality and DD was calculated. A linear regression model was used to examine the association between DD and adjacent EBQ and VBQ. RESULTS: This study included 569 lumbar segments from 130 inpatients. Cranial and caudal EBQ decreased with the increase of the Pfirrmann grade. The discs with Pfirrmann grade 5 had significantly lower caudal EBQ than the discs with Pfirrmann grades 2, 3, and 4. In the osteoporosis patients, the Pfirrmann grades negatively correlated both with the cranial EBQ and caudal EBQ. Pfirrmann grade greater than 4 was an independent contributor to the cranial EBQ, whereas greater than 3 was an independent contributor to the caudal EBQ. CONCLUSIONS: Disc degeneration grades correlated with the EBQ but not with the VBQ. In patients with lumbar spinal stenosis or disc herniation, DD contributes to the denser bone in the sub-endplate, but not in the whole vertebral body.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Estenose Espinal , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Corpo Vertebral , Estenose Espinal/diagnóstico por imagem , Estudos Retrospectivos , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
19.
Int J Mol Sci ; 23(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36499639

RESUMO

Diabetic nephropathy (DN) exacerbates renal tissue damage and is a major cause of end-stage renal disease. Reactive oxygen species play a vital role in hyperglycemia-induced renal injury. This study examined whether the oral hypoglycemic drug acarbose (Ab) could attenuate the progression of DN in type 2 diabetes mellitus mice. In this study, 50 mg/kg body weight of Ab was administered to high-fat diet (HFD)-fed db/db mice. Their body weight was recorded every week, and the serum glucose concentration was monitored every 2 weeks. Following their euthanasia, the kidneys of mice were analyzed through hematoxylin and eosin, periodic acid Schiff, Masson's trichrome, and immunohistochemistry (IHC) staining. The results revealed that Ab stabilized the plasma glucose and indirectly improved the insulin sensitivity and renal functional biomarkers in diabetic mice. In addition, diabetes-induced glomerular hypertrophy, the saccharide accumulation, and formation of collagen fiber were reduced in diabetic mice receiving Ab. Although the dosages of Ab cannot decrease the blood sugar in db/db mice, our results indicate that Ab alleviates glucolipotoxicity-induced DN by inhibiting kidney fibrosis-related proteins through the Ras/ERK pathway.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Acarbose/farmacologia , Rim/metabolismo , Peso Corporal , Camundongos Endogâmicos C57BL
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