Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Biol Chem ; 299(7): 104874, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37257819

RESUMEN

Force and torque spectroscopy have provided unprecedented insights into the mechanical properties, conformational transitions, and dynamics of DNA and DNA-protein complexes, notably nucleosomes. Reliable single-molecule manipulation measurements require, however, specific and stable attachment chemistries to tether the molecules of interest. Here, we present a functionalization strategy for DNA that enables high-yield production of constructs for torsionally constrained and very stable attachment. The method is based on two subsequent PCRs: first ∼380 bp long DNA strands are generated that contain multiple labels, which are used as "megaprimers" in a second PCR to generate ∼kbp long double-stranded DNA constructs with multiple labels at the respective ends. To achieve high-force stability, we use dibenzocyclooctyne-based click chemistry for covalent attachment to the surface and biotin-streptavidin coupling to the bead. The resulting tethers are torsionally constrained and extremely stable under load, with an average lifetime of 70 ± 3 h at 45 pN. The high yield of the approach enables nucleosome reconstitution by salt dialysis on the functionalized DNA, and we demonstrate proof-of-concept measurements on nucleosome assembly statistics and inner turn unwrapping under force. We anticipate that our approach will facilitate a range of studies of DNA interactions and nucleoprotein complexes under forces and torques.


Asunto(s)
ADN , Nucleosomas , ADN/química , Fenómenos Mecánicos , Fenómenos Biofísicos , Reacción en Cadena de la Polimerasa
2.
Nucleic Acids Res ; 50(10): 5726-5738, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35640616

RESUMEN

The structure and properties of DNA depend on the environment, in particular the ion atmosphere. Here, we investigate how DNA twist -one of the central properties of DNA- changes with concentration and identity of the surrounding ions. To resolve how cations influence the twist, we combine single-molecule magnetic tweezer experiments and extensive all-atom molecular dynamics simulations. Two interconnected trends are observed for monovalent alkali and divalent alkaline earth cations. First, DNA twist increases monotonously with increasing concentration for all ions investigated. Second, for a given salt concentration, DNA twist strongly depends on cation identity. At 100 mM concentration, DNA twist increases as Na+ < K+ < Rb+ < Ba2+ < Li+ ≈ Cs+ < Sr2+ < Mg2+ < Ca2+. Our molecular dynamics simulations reveal that preferential binding of the cations to the DNA backbone or the nucleobases has opposing effects on DNA twist and provides the microscopic explanation of the observed ion specificity. However, the simulations also reveal shortcomings of existing force field parameters for Cs+ and Sr2+. The comprehensive view gained from our combined approach provides a foundation for understanding and predicting cation-induced structural changes both in nature and in DNA nanotechnology.


Asunto(s)
ADN , Simulación de Dinámica Molecular , Cationes , Cationes Bivalentes , Cationes Monovalentes , ADN/química , Sodio , Cloruro de Sodio
3.
Chin J Traumatol ; 27(5): 305-310, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38641468

RESUMEN

PURPOSE: Intramedullary nailing is the preferred internal fixation technique for the treatment of subtrochanteric fractures because of its biomechanical advantages. However, no definitive conclusion has been reached regarding whether combined cable cerclage is required during intramedullary nailing treatment. This study is performed to compare the clinical effects of intramedullary nailing with cerclage and non-cerclage wiring in the treatment of irreducible spiral subtrochanteric fractures. METHODS: Patients with subtrochanteric fractures admitted to our center from January 2013 to December 2021 were retrospectively analyzed. The patients were enrolled in the case-control study according to the inclusion and exclusion criteria and divided into the non-cerclage group and the cerclage group. The patients' clinical data, including the operative time, intraoperative blood loss, hospital stay, reoperation rate, fracture union time, and Harris hip score, were compared between these 2 groups. Categorical variables were compared using Chi-square or Fisher's exact test. Continuous variables with normal distribution were presented as mean ± standard deviation and analyzed with Student's t-test. Non-normally distributed variables were expressed as median (Q1, Q3) and assessed using the Mann-Whitney test. A p < 0.05 was considered significant. RESULTS: In total, 69 patients were included in the study (35 patients in the non-cerclage group and 34 patients in the cerclage group). The baseline data of the 2 groups were comparable. There were no significant difference in the length of hospital stay (z = -0.391, p = 0.696), operative time (z = -1.289, p = 0.197), or intraoperative blood loss (z = -1.321, p = 0.186). However, compared with non-cerclage group, the fracture union time was shorter (z = -5.587, p < 0.001), the rate of nonunion was lower (χ2 = 6.030, p = 0.03), the anatomical reduction rate was higher (χ2 = 5.449, p = 0.03), and the Harris hip score was higher (z = -2.99, p = 0.003) in the cerclage group, all with statistically significant differences. CONCLUSIONS: Intramedullary nailing combined with cable cerclage wiring is a safe and reliable technique for the treatment of irreducible subtrochanteric fractures. This technique can improve the reduction effect, increase the stability of fracture fixation, shorten the fracture union time, reduce the occurrence of nonunion, and contribute to the recovery of hip joint function.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Humanos , Fracturas de Cadera/cirugía , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Estudios de Casos y Controles , Anciano , Adulto , Hilos Ortopédicos , Tiempo de Internación/estadística & datos numéricos , Tempo Operativo , Resultado del Tratamiento
4.
J Cell Mol Med ; 28(5): e17931, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37700501

RESUMEN

Peroxisome proliferator-activated receptors (PPARs) are transcription factors belonging to the nuclear receptor family. There are three subtypes of PPARs, including PPAR-α, PPAR-ß/δ and PPAR-γ. They are expressed in different tissues and act by regulating the expression of target genes in the form of binding to ligands. Various subtypes of PPAR have been shown to have significant roles in a wide range of biological processes including lipid metabolism, body energy homeostasis, cell proliferation and differentiation, bone formation, tissue repair and remodelling. Recent studies have found that PPARs are closely related to tumours. They are involved in cancer cell growth, angiogenesis and tumour immune response, and are essential components in tumour progression and metastasis. As such, they have become a target for cancer therapy research. In this review, we discussed the current state of knowledge on the involvement of PPARs in cancer, including their role in tumourigenesis, the impact of PPARs in tumour microenvironment and the potential of using PPARs combinational therapy to treat cancer by targeting essential signal pathways, or as adjuvants to boost the effects of current chemo and immunotherapies. Our review highlights the complexity of PPARs in cancer and the need for a better understanding of the mechanism in order to design effective cancer therapies.

5.
BMC Geriatr ; 22(1): 3, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34979925

RESUMEN

BACKGROUND: The coexistence of sarcopenia and dementia in aging populations is not uncommon, and they may share common risk factors and pathophysiological pathways. This study aimed to evaluate the relationship between brain atrophy and low lean mass in the elderly with impaired cognitive function. METHODS: This cross-sectional study included 168 elderly patients who visited the multi-disciplinary dementia outpatient clinic at Kaohsiung Chang Gung Memorial Hospital for memory issues, between 2017 and 2019. The body composition was assessed by dual energy X-ray absorptiometry (DEXA) and CT based skeletal muscle index including L3 skeletal muscle index (L3SMI) and masseter muscle mass index (MSMI). The brain atrophy assessment was measured by CT based visual rating scale. Possible predictors of low lean mass in the elderly with cognitive impairement were identified by binary logistic regression. ROC curves were generated from binary logistic regression. RESULTS: Among the 81 participants, 43 (53%) remained at a normal appendicular skeletal muscle index (ASMI), whereas 38 (47%) showed low ASMI. Compared with the normal ASMI group, subjects with low ASMI exhibited significantly lower BMI, L3SMI, and MSMI (all p < 0.05), and showed significant brain atrophy as assessed by visual rating scale (p < 0.001). The accuracy of predictive models for low ASMI in the elderly with cognitive impairment were 0.875, (Area under curve (AUC) = 0.926, 95% confidence interval [CI] 0.844-0.972) in model 1 (combination of BMI, GCA and L3SMI) and 0.885, (Area under curve (AUC) = 0.931, [CI] 0.857-0.979) in model 2 (combination of BMI, GCA and MSMI). CONCLUSIONS: Global cortical atrophy and body mass index combined with either L3 skeletal muscle index or masseter skeletal muscle index can predict low lean mass in the elderly with cognitive impairment.


Asunto(s)
Disfunción Cognitiva , Sarcopenia , Absorciometría de Fotón , Anciano , Composición Corporal , Índice de Masa Corporal , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Estudios Transversales , Humanos , Vida Independiente , Músculo Esquelético/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen , Sarcopenia/epidemiología , Tomografía Computarizada por Rayos X
6.
Curr Ther Res Clin Exp ; 96: 100666, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464291

RESUMEN

Background: Spinal surgery is associated with severe pain within the first few days after surgery. Opioids are commonly used to control postoperative pain, but these can lead to postoperative nausea and vomiting (PONV). Therefore, use of more effective and better-tolerated agents would be beneficial for these patients. Serotonin receptor antagonists, such as ramosetron, have been used to reduce PONV in patients receiving anesthesia. Objective: We conducted a meta-analysis of published randomized controlled trials (RCTs) to compare the efficacy and tolerance of ramosetron to prevent PONV after spinal surgery. Methods: Medline, Embase, Cochrane Library, and Science Citation Index databases were systematically searched for relevant RCT articles published between January 1979 and November 2020. Full text articles restricted to English language that described RCTs comparing the use of ramosetron with other serotonin antagonists to treat PONV following spinal surgery in adult patients were considered for meta-analysis. Two reviewers independently performed study selection, quality assessment, and data extraction of all articles. Differences were resolved by a third reviewer. Results: The search identified 88 potentially relevant articles, of which only 3 met our selection criteria. Study drugs were administered at the end of spinal surgery in all 3 included articles. The meta-analysis revealed that ramosetron (0.3 mg) reduced the pain score (mean difference = -0.66; 95% CI -1.02 to -0.30), lowered the risk of PONV (risk ratio = 0.86; 95% CI, 0.76-0.97), and postoperative vomiting (risk ratio = 0.32; 95% CI, 0.17-0.60), and limited the use of rescue antiemetics (risk ratio = 0.66; 95% CI, 0.45-0.96) after spinal surgery. However, there were no significant differences in the incidence of postoperative nausea, the use of rescue pain medications, the number of rescue analgesics required, and the risk of discontinuation of patient-controlled analgesia between ramosetron and palonosetron (0.075 mg) or ondansetron (4 mg). There were no statistically significant differences in the risk of adverse events among the 3 medications. Conclusions: This meta-analysis of 3 RCTs showed that ramosetron reduced the risk of PONV and POV, limited the use of rescue antiemetics, reduced the postoperative pain score, and did not increase the risk of discontinuing patient-controlled analgesia compared with palonosetron or ondansetron after spinal surgery in 3 RCTs. Therefore, this meta-analysis indicates that ramosetron is an effective and well tolerated antiemetic that can be used to prevent PONV following spinal surgery in adult patients. PROSPERO identifier: CRD42020223596 (Curr Ther Res Clin Exp. 2022; 83:XXX-XXX)© 2022 Elsevier HS Journals, Inc.

7.
J Am Chem Soc ; 143(15): 5815-5825, 2021 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-33831300

RESUMEN

Telomeres are essential for chromosome maintenance. Cdc13 is a single-stranded telomeric DNA binding protein that caps telomeres and regulates telomerase function in yeast. Although specific binding of Cdc13 to telomeric DNA is critical for telomere protection, the detail mechanism how Cdc13-DNA complex protects telomere is unclear. Using two single-molecule methods, tethered particle motion and atomic force microscopy, we demonstrate that specific binding of Cdc13 on single-stranded telomeric DNA shortens duplex DNA into distinct states differed by ∼70-80 base pairs. DNA shortening by Cdc13 is dynamic and independent of duplex DNA sequences or length. Significantly, we found that Pif1 helicase is incapable of removing Cdc13 from the shortened DNA-Cdc13 complex, suggesting that Cdc13 forms structurally stable complex by shortening of the bound DNA. Together our data identified shortening of DNA by Cdc13 and provided an indication for efficient protection of telomere ends by the shortened DNA-Cdc13 complex.


Asunto(s)
ADN de Cadena Simple/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Unión a Telómeros/metabolismo , ADN Helicasas/química , ADN Helicasas/genética , ADN Helicasas/metabolismo , ADN de Cadena Simple/química , Dimerización , Microscopía de Fuerza Atómica , Mutagénesis Sitio-Dirigida , Unión Proteica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Telómero/química , Telómero/metabolismo , Acortamiento del Telómero , Proteínas de Unión a Telómeros/química
8.
Eur J Cancer Care (Engl) ; 29(4): e13233, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32100388

RESUMEN

OBJECTIVE: To explore the relationship of exercise timing (exercising close to bedtime, exercising in daylight and maintaining fixed exercise schedule) with sleep quality, fatigue and rest-activity rhythms among lung cancer patients in Taiwan. METHODS: Results from 43 lung cancer patients who were assigned and adhered to the exercise intervention in a 12-week randomised controlled trial were analysed. The MD Anderson Symptom Inventory and Pittsburgh Sleep Quality Index (PSQI) were administered. Actigraphs were used to assess rest-activity rhythms (in-bed less than out-of-bed dichotomy index, I < O) and objective sleep parameters, including total sleep time (TST) and sleep onset latency (SOL). RESULTS: Patients who exercised >4 hr before bedtime had significant improvement in fatigue (p < .0001), sleep quality (p = .012 for PSQI; p = .037 for TST; p = .017 for SOL) and rest-activity rhythms (p = .048 for I < O). Furthermore, patients who exercised with daylight exposure had a significant improvement in fatigue (p = .037) and sleep quality (p = .039 for PSQI). CONCLUSIONS: Exercising >4 hr before bedtime with daylight exposure is associated with improvement in rest-activity rhythms, sleep quality and fatigue in lung cancer patients. The causal relationship requires further investigation with experimental design.


Asunto(s)
Ritmo Circadiano , Terapia por Ejercicio/métodos , Fatiga/rehabilitación , Neoplasias Pulmonares/rehabilitación , Descanso , Sueño , Actigrafía , Adulto , Anciano , Anciano de 80 o más Años , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Taiwán , Factores de Tiempo
10.
Mol Cell Neurosci ; 85: 29-44, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28830718

RESUMEN

Lipids are predominant components of the brain and key regulators for neural structure and function. The neuropsychopharmacological effect of cocaine has been intensively investigated; however, the impact of cocaine on brain lipid profiles is largely unknown. In this study, we used a LC-MS-based lipidomic approach to investigate the impact of cocaine on brain lipidome in two mouse models, cocaine-conditioned place preference (CPP) and hyperlocomotor models and the lipidome was profoundly modified in the nucleus accumbens (NAc) and striatum respectively. We comprehensively analyzed the lipids among 21 subclasses across 7 lipid classes and found that cocaine profoundly modified brain lipidome. Notably, the lipid metabolites significantly modified were sphingolipids and glycerophospholipids in the NAc, showing a decrease in ceramide and an increase in its up/downstream metabolites levels, and decrease lysophosphatidylcholine (LPC) and lysophosphoethanolamine (LPE) and increase phosphatidylcholine (PC) and phosphatidylethanolamines (PE) levels, respectively. Moreover, long and polyunsaturated fatty acid phospholipids were also markedly increased in the NAc. Our results show that cocaine can markedly modify brain lipidomic profiling. These findings reveal a link between the modified lipidome and psychopharmacological effect of cocaine, providing a new insight into the mechanism of cocaine addiction.


Asunto(s)
Química Encefálica/efectos de los fármacos , Encéfalo/efectos de los fármacos , Cocaína/farmacología , Inhibidores de Captación de Dopamina/farmacología , Lípidos , Animales , Encéfalo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL
11.
Support Care Cancer ; 23(12): 3545-53, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25855040

RESUMEN

PURPOSE: To examine the effect of physical activity on the physical and psychosocial symptoms of lung cancer survivors. METHODS: A longitudinal design was used in this study. Participants were recruited from the chest and surgical departments of medical centers in Taiwan. The instruments used were the Godin Leisure-Time Exercise Questionnaire and the Taiwanese version of the M.D. Anderson Symptom Inventory. RESULTS: In total, 185 survivors were followed up for 6 months (response rate 66%). Disturbed sleep was the most prevalent symptom in the participants. A generalized estimating equation (GEE) method was employed to analyze the relationships among intensity of physical activity, symptom severity, and symptom interference in the daily life of the participants. Regarding symptom severity, significant differences were observed in fatigue, drowsiness, and disturbed sleep between the participants who engaged in moderate physical activity and those who did not engage in any physical activity. Regarding symptom interference, the participants who engaged in light physical activity experienced a significantly lower level of symptom interference than did those with a sedentary lifestyle. CONCLUSION: This is the first study to explore the role of physical activity in alleviating symptoms in lung cancer survivors by using the GEE method. The results suggest that physical activity plays an essential role in alleviating the physical and psychological symptoms of lung cancer survivors.


Asunto(s)
Neoplasias Pulmonares/rehabilitación , Actividad Motora/fisiología , Adulto , Anciano , Ejercicio Físico/fisiología , Ejercicio Físico/psicología , Fatiga/epidemiología , Femenino , Humanos , Estudios Longitudinales , Neoplasias Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Trastornos del Sueño-Vigilia/epidemiología , Encuestas y Cuestionarios , Sobrevivientes , Taiwán/epidemiología
12.
Foot Ankle Int ; 45(8): 824-832, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38721810

RESUMEN

BACKGROUND: This study evaluates the outcomes of fibular intramedullary nails (IMNs) compared to traditional plates and screws (PS) in the surgical treatment of unstable ankle injuries in patients aged ≥65 years. METHOD: We conducted a retrospective study involving 32 elderly patients with unstable ankle fractures treated with IMNs from 2010 to 2022. A comparison was made with 125 case-control patients treated with PS during the same period. Outcomes compared included postoperative wound and nonwound complications, surgical reduction, union rates, implant removal rates, and the Olerud Molander Ankle Score (OMAS) at a minimum follow-up of 2 years. RESULTS: The IMN group had a higher incidence of high-energy injuries, open fractures, concomitant surgery, and perioperative transfusion requirements than the PS group. Additionally, the IMN group developed fewer wound-related (3.1% vs 20% in the PS group, P = .043) and non-wound-related complications (18.8% vs 39.2% in the PS group, P = .030). Both groups had similar initial weightbearing restrictions, fracture union times, mean OMAS scores, rates of malunion or nonunion, and delayed implant removal times. Notably, there were significant differences in the quality and adequacy of mortise alignment between the groups (good: 53.1% in IMN group vs 79.2% in PS group, fair: 46.9% in IMN group vs 20.8% in PS group, P = .006). CONCLUSION: Although the IMN group had an inferior outcome in the quality and adequacy of mortise reduction compared with the PS group, elderly patients with ankle fractures treated with IMN showed comparable functional outcomes to those treated with PS but with lower complication rates. Future research in this area will provide vital information for developing optimal treatment strategies, thereby improving the overall care of elderly patients with ankle fractures.


Asunto(s)
Fracturas de Tobillo , Clavos Ortopédicos , Placas Óseas , Fijación Intramedular de Fracturas , Humanos , Estudios Retrospectivos , Fracturas de Tobillo/cirugía , Anciano , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Masculino , Femenino , Anciano de 80 o más Años , Peroné/lesiones , Peroné/cirugía , Complicaciones Posoperatorias , Estudios de Casos y Controles , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación
13.
Cytokine Growth Factor Rev ; 75: 101-109, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37658030

RESUMEN

Ferroptosis is a type of cell death characterized by iron-dependent phospholipid peroxidation and reactive oxygen species overproduction. Ferroptosis induces immunogenic cell death and elicits anti-tumor immune responses, playing an important role in cancer immunotherapy. Ferroptosis suppression in cancer cells impairs its immunotherapeutic efficacy. To overcome this issue, ferroptosis inducers (FINs) have been combined with other cancer therapies to create an anti-tumor immune microenvironment. However, the ferroptosis-based crosstalk between immune and tumor cells is complex because oxidative products released by ferroptotic tumor cells impair the functions of anti-tumor immune cells, resulting in immunotherapeutic resistance. In the present article, we have reviewed ferroptosis in tumor and immune cells and summarized the crosstalk between ferroptotic tumor cells and the immune microenvironment. Based on the existing literature, we have further discussed future perspectives on opportunities for combining ferroptosis-targeted therapies with cancer immunotherapies.


Asunto(s)
Ferroptosis , Neoplasias , Humanos , Inmunoterapia , Neoplasias/terapia , Especies Reactivas de Oxígeno , Microambiente Tumoral
14.
J Mol Biol ; 436(16): 168671, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38908785

RESUMEN

Nucleosomes are the basic compaction unit of chromatin and nucleosome structure and their higher-order assemblies regulate genome accessibility. Many post-translational modifications alter nucleosome dynamics, nucleosome-nucleosome interactions, and ultimately chromatin structure and gene expression. Here, we investigate the role of two post-translational modifications associated with actively transcribed regions, H3K36me3 and H4K5/8/12/16ac, in the contexts of tri-nucleosome arrays that provide a tractable model system for quantitative single-molecule analysis, while enabling us to probe nucleosome-nucleosome interactions. Direct visualization by AFM imaging reveals that H3K36me3 and H4K5/8/12/16ac nucleosomes adopt significantly more open and loose conformations than unmodified nucleosomes. Similarly, magnetic tweezers force spectroscopy shows a reduction in DNA outer turn wrapping and nucleosome-nucleosome interactions for the modified nucleosomes. The results suggest that for H3K36me3 the increased breathing and outer DNA turn unwrapping seen in mononucleosomes propagates to more open conformations in nucleosome arrays. In contrast, the even more open structures of H4K5/8/12/16ac nucleosome arrays do not appear to derive from the dynamics of the constituent mononucleosomes, but are driven by reduced nucleosome-nucleosome interactions, suggesting that stacking interactions can overrule DNA breathing of individual nucleosomes. We anticipate that our methodology will be broadly applicable to reveal the influence of other post-translational modifications and to observe the activity of nucleosome remodelers.


Asunto(s)
Histonas , Nucleosomas , Procesamiento Proteico-Postraduccional , Nucleosomas/metabolismo , Nucleosomas/química , Histonas/metabolismo , Histonas/química , Epigénesis Genética , Código de Histonas , ADN/metabolismo , ADN/química , Conformación de Ácido Nucleico , Metilación , Microscopía de Fuerza Atómica/métodos
15.
Nat Commun ; 15(1): 1987, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443336

RESUMEN

Abundant macrophage infiltration and altered tumor metabolism are two key hallmarks of glioblastoma. By screening a cluster of metabolic small-molecule compounds, we show that inhibiting glioblastoma cell glycolysis impairs macrophage migration and lactate dehydrogenase inhibitor stiripentol emerges as the top hit. Combined profiling and functional studies demonstrate that lactate dehydrogenase A (LDHA)-directed extracellular signal-regulated kinase (ERK) pathway activates yes-associated protein 1 (YAP1)/ signal transducer and activator of transcription 3 (STAT3) transcriptional co-activators in glioblastoma cells to upregulate C-C motif chemokine ligand 2 (CCL2) and CCL7, which recruit macrophages into the tumor microenvironment. Reciprocally, infiltrating macrophages produce LDHA-containing extracellular vesicles to promote glioblastoma cell glycolysis, proliferation, and survival. Genetic and pharmacological inhibition of LDHA-mediated tumor-macrophage symbiosis markedly suppresses tumor progression and macrophage infiltration in glioblastoma mouse models. Analysis of tumor and plasma samples of glioblastoma patients confirms that LDHA and its downstream signals are potential biomarkers correlating positively with macrophage density. Thus, LDHA-mediated tumor-macrophage symbiosis provides therapeutic targets for glioblastoma.


Asunto(s)
Glioblastoma , Animales , Humanos , Ratones , Glioblastoma/genética , L-Lactato Deshidrogenasa/genética , Lactato Deshidrogenasa 5 , Ácido Láctico , Simbiosis , Microambiente Tumoral
16.
bioRxiv ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39314325

RESUMEN

Understanding the impact of genetic alterations on epigenomic phenotypes during breast cancer progression is challenging with unimodal measurements. Here, we report wellDA-seq, the first high-genomic resolution, high-throughput method that can simultaneously measure the whole genome and chromatin accessibility profiles of thousands of single cells. Using wellDA-seq, we profiled 22,123 single cells from 2 normal and 9 tumors breast tissues. By directly mapping the epigenomic phenotypes to genetic lineages across cancer subclones, we found evidence of both genetic hardwiring and epigenetic plasticity. In 6 estrogen-receptor positive breast cancers, we directly identified the ancestral cancer cells, and found that their epithelial cell-of-origin was Luminal Hormone Responsive cells. We also identified cell types with copy number aberrations (CNA) in normal breast tissues and discovered non-epithelial cell types in the microenvironment with CNAs in breast cancers. These data provide insights into the complex relationship between genetic alterations and epigenomic phenotypes during breast tumor evolution.

17.
Dev Cell ; 59(11): 1475-1486.e5, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38574731

RESUMEN

Telomere dynamics are linked to aging hallmarks, and age-associated telomere loss fuels the development of epithelial cancers. In Apc-mutant mice, the onset of DNA damage associated with telomere dysfunction has been shown to accelerate adenoma initiation via unknown mechanisms. Here, we observed that Apc-mutant mice engineered to experience telomere dysfunction show accelerated adenoma formation resulting from augmented cell competition and clonal expansion. Mechanistically, telomere dysfunction induces the repression of EZH2, resulting in the derepression of Wnt antagonists, which causes the differentiation of adjacent stem cells and a relative growth advantage to Apc-deficient telomere dysfunctional cells. Correspondingly, in this mouse model, GSK3ß inhibition countered the actions of Wnt antagonists on intestinal stem cells, resulting in impaired adenoma formation of telomere dysfunctional Apc-mutant cells. Thus, telomere dysfunction contributes to cancer initiation through altered stem cell dynamics, identifying an interception strategy for human APC-mutant cancers with shortened telomeres.


Asunto(s)
Proteína de la Poliposis Adenomatosa del Colon , Células Madre , Telómero , Animales , Ratones , Telómero/metabolismo , Proteína de la Poliposis Adenomatosa del Colon/genética , Proteína de la Poliposis Adenomatosa del Colon/metabolismo , Células Madre/metabolismo , Células Madre/patología , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Adenoma/patología , Adenoma/genética , Adenoma/metabolismo , Intestinos/patología , Diferenciación Celular , Humanos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/genética , Daño del ADN , Ratones Endogámicos C57BL , Vía de Señalización Wnt
18.
Eur J Med Res ; 28(1): 310, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37658421

RESUMEN

BACKGROUND: Although the role of adjuvant chemotherapy (CT) for resectable biliary tract cancer (BTC) is gradually recognized, the benefit of adjuvant chemoradiotherapy (CRT) is still controversial. Our study is designed to compare the prognosis of CRT versus CT in BCT patients. METHODS: Clinicopathologic characteristics of patients with operable gallbladder cancer (GBCA), intrahepatic bile duct cancer (IHBDC), or extrahepatic bile duct cancer (EHBDC) were obtained from the Surveillance, Epidemiology and End Results (SEER) database (2004-2015). Univariate and multivariate analyses were performed to identify prognostic factors for overall survival (OS). Selection bias were reduced by propensity-score matching (PSM). Kaplan-Meier analysis was used to estimate the survival time. RESULTS: Within 922 patients, 53.9% received adjuvant CRT, and 46.1% received adjuvant CT. Multivariate analysis showed age, primary tumor site, T stage, N stage, tumor size, number of removed lymph nodes, and treatment were independent risk factors for OS. Similar improvement of CRT on survival was identified by PSM in the matched cohort compared with CT (28.0 months vs. 25.0 months, p = 0.033), particularly in GBCA cohort (25.0 months vs. 19.0 months, p = 0.003). Subgroup analysis indicated CRT improved outcomes of patients with age ≥ 60, female, lymph nodes positive, tumor size ≥ 5 cm, and none removed lymph node diseases. CONCLUSION: Adjuvant CRT correlated with improved survival in patients with resected BTC compared with adjuvant CT, particularly in GBCAs. In addition, patients with age ≥ 60, female, lymph nodes positive, tumor size ≥ 5 cm, and none removed lymph node diseases may receive more benefits from adjuvant CRT.


Asunto(s)
Neoplasias de los Conductos Biliares , Neoplasias del Sistema Biliar , Neoplasias de la Vesícula Biliar , Humanos , Femenino , Quimioradioterapia Adyuvante , Puntaje de Propensión
19.
Front Oncol ; 13: 1104910, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37064118

RESUMEN

Background: Although anaplastic lymphoma kinase tyrosine kinase inhibitors (ALK-TKIs) have impressive response in advanced lung adenocarcinoma with anaplastic lymphoma kinase (ALK) fusion, no guidelines point to the potential benefits of neoadjuvant ALK-TKIs for N3 unresectable locally advanced lung cancer. Current ongoing clinical trials mainly focus on the efficacy of neoadjuvant ALK-TKIs in resectable locally advanced lung cancer and ignore the role of neoadjuvant ALK-TKIs in N3 unresectable locally advanced lung cancer. Materials and methods: We report a lung cancer case with a novel INTS10-ALK and EML4-ALK rearrangement that achieved complete pathologic response to neoadjuvant crizotinib. We conducted molecular pathologic analysis by using next-generation sequencing (NGS). Genomic DNA was extracted from formalin-fixed paraffin-embedded (FFPE) samples and profiled using a capture-based targeted sequencing panel consisting of 56 lung cancer-related genes. Results: Our study reported a patient with stage IIIB-N3 lung adenocarcinoma with an unreported dual ALK rearrangement (INTS10-ALK and EML4-ALK) who received 5 months of crizotinib, followed by R0 right upper lobectomy, achieving complete pathological response (ypT0 ypN0). No recurrence of the tumor was found for 3 years postoperatively. Conclusion: The case supports the strategy of neoadjuvant ALK inhibitors for N3 unresectable locally advanced lung cancer, expanding the spectrum of treatment of stage IIIB-N3 lung cancer.

20.
Acta Biomater ; 170: 344-359, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37607615

RESUMEN

Poly(polyol sebacate) (PPS) polymer family has been recognized as promising biomaterials for biomedical applications with their characteristics of easy production, elasticity, biodegradation, and cytocompatibility. Poly(xylitol sebacate)-co-poly(ethylene glycol) (PXS-co-PEG) has been developed to fabricate PPS-based hydrogels; however, current PXS-co-PEG hydrogels presented limited properties and functions due to the limitations of the crosslinkers and crosslinking chemistry used in the hydrogel formation. Here, we fabricate a new type of PXS-co-PEG hydrogels through the use of multifunctional crosslinkers as well as dynamic bonds. In our design, polyethyleneimine-polydopamine (PEI-PDA) macromers are utilized to crosslink aldehyde-functionalized PXS-co-PEG (APP) through imine bonds and hydrogen bonds. PEI-PDA/APP hydrogels present multiple functional properties (e.g., fluorescent, elastomeric, biodegradable, self-healing, bioadhesive, antioxidant, and antibacterial behaviors). These properties of PEI-PDA/APP hydrogels can be fine-tuned by changing the PDA grafting degrees in the PEI-PDA crosslinkers. Most importantly, PEI-PDA/APP hydrogels are considered promising wound dressings to promote tissue remodeling and prevent bacterial infection in vivo. Taken together, PEI-PDA/APP hydrogels have been demonstrated as versatile biomaterials to provide multiple tailorable properties and desirable functions to expand the utility of PPS-based hydrogels for advanced biomedical applications. STATEMENT OF SIGNIFICANCE: Various strategies have been developed to fabricate poly(polyol sebacate) (PPS)-based hydrogels. However, current PPS-based hydrogels present limited properties and functions due to the limitations of the crosslinkers and crosslinking chemistry used in the hydrogel formation. This work describes that co-engineering crosslinkers and interfacial crosslinking is a promising approach to synthesizing a new type of poly(xylitol sebacate)-co-poly(ethylene glycol) (PXS-co-PEG) hydrogels as multifunctional hydrogels to expand the utility of PPS-based hydrogels for advanced biomedical applications. The fabricated hydrogels present multiple functional properties (e.g., fluorescent, biodegradable, elastomeric, self-healing, bioadhesive, antioxidative, and antibacterial), and these properties can be fine-tuned by the defined crosslinkers. The fabricated hydrogels are also used as promising wound dressing biomaterials to exhibit promoted tissue remodeling and prevent bacterial infection in vivo.


Asunto(s)
Infecciones Bacterianas , Xilitol , Humanos , Polietilenglicoles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/química , Antioxidantes/farmacología , Cicatrización de Heridas , Hidrogeles/farmacología , Hidrogeles/química , Polietileneimina , Antibacterianos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA