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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 â¼380 bp long DNA strands are generated that contain multiple labels, which are used as "megaprimers" in a second PCR to generate â¼kbp 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.
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DNA , Nucleossomos , DNA/química , Fenômenos Mecânicos , Fenômenos Biofísicos , Reação em Cadeia da PolimeraseRESUMO
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.
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DNA , Simulação de Dinâmica Molecular , Cátions , Cátions Bivalentes , Cátions Monovalentes , DNA/química , Sódio , Cloreto de SódioRESUMO
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.
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Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Fraturas do Quadril/cirurgia , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/instrumentação , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Estudos de Casos e Controles , Idoso , Adulto , Fios Ortopédicos , Tempo de Internação/estatística & dados numéricos , Duração da Cirurgia , Resultado do TratamentoRESUMO
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.
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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.
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Disfunção Cognitiva , Sarcopenia , Absorciometria de Fóton , Idoso , Composição Corporal , Índice de Massa Corporal , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Estudos Transversais , Humanos , Vida Independente , Músculo Esquelético/diagnóstico por imagem , Sarcopenia/diagnóstico por imagem , Sarcopenia/epidemiologia , Tomografia Computadorizada por Raios XRESUMO
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 differenceâ¯=â¯-0.66; 95% CI -1.02 to -0.30), lowered the risk of PONV (risk ratioâ¯=â¯0.86; 95% CI, 0.76-0.97), and postoperative vomiting (risk ratioâ¯=â¯0.32; 95% CI, 0.17-0.60), and limited the use of rescue antiemetics (risk ratioâ¯=â¯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.
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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 â¼70-80 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.
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DNA de Cadeia Simples/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , DNA Helicases/química , DNA Helicases/genética , DNA Helicases/metabolismo , DNA de Cadeia Simples/química , Dimerização , Microscopia de Força Atômica , Mutagênese Sítio-Dirigida , Ligação Proteica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Telômero/química , Telômero/metabolismo , Encurtamento do Telômero , Proteínas de Ligação a Telômeros/químicaRESUMO
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.
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Ritmo Circadiano , Terapia por Exercício/métodos , Fadiga/reabilitação , Neoplasias Pulmonares/reabilitação , Descanso , Sono , Actigrafia , Adulto , Idoso , Idoso de 80 Anos ou mais , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan , Fatores de TempoRESUMO
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.
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Química Encefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Lipídeos , Animais , Encéfalo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
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.
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Neoplasias Pulmonares/reabilitação , Atividade Motora/fisiologia , Adulto , Idoso , Exercício Físico/fisiologia , Exercício Físico/psicologia , Fadiga/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transtornos do Sono-Vigília/epidemiologia , Inquéritos e Questionários , Sobreviventes , Taiwan/epidemiologiaRESUMO
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.
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Fraturas do Tornozelo , Pinos Ortopédicos , Placas Ósseas , Fixação Intramedular de Fraturas , Humanos , Estudos Retrospectivos , Fraturas do Tornozelo/cirurgia , Idoso , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/instrumentação , Masculino , Feminino , Idoso de 80 Anos ou mais , Fíbula/lesões , Fíbula/cirurgia , Complicações Pós-Operatórias , Estudos de Casos e Controles , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentaçãoRESUMO
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.
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Ferroptose , Neoplasias , Humanos , Imunoterapia , Neoplasias/terapia , Espécies Reativas de Oxigênio , Microambiente TumoralRESUMO
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.
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Histonas , Nucleossomos , Processamento de Proteína Pós-Traducional , Nucleossomos/metabolismo , Nucleossomos/química , Histonas/metabolismo , Histonas/química , Epigênese Genética , Código das Histonas , DNA/metabolismo , DNA/química , Conformação de Ácido Nucleico , Metilação , Microscopia de Força Atômica/métodosRESUMO
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.
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Glioblastoma , Animais , Humanos , Camundongos , Glioblastoma/genética , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5 , Ácido Láctico , Simbiose , Microambiente TumoralRESUMO
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.
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Proteína da Polipose Adenomatosa do Colo , Células-Tronco , Telômero , Animais , Camundongos , Telômero/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Células-Tronco/metabolismo , Células-Tronco/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Adenoma/patologia , Adenoma/genética , Adenoma/metabolismo , Intestinos/patologia , Diferenciação Celular , Humanos , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Dano ao DNA , Camundongos Endogâmicos C57BL , Via de Sinalização WntRESUMO
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.
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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.
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Neoplasias dos Ductos Biliares , Neoplasias do Sistema Biliar , Neoplasias da Vesícula Biliar , Humanos , Feminino , Quimiorradioterapia Adjuvante , Pontuação de PropensãoRESUMO
Nanocomposite (NC) hydrogels used for sonodynamic therapy (SDT) face challenges such as lacking interfacial interactions between the polymers and nanomaterials as well as presenting uneven dispersion of nanomaterials in the hydrogel network, reducing their mechanical properties and treatment efficiency. Here, we demonstrate a promising approach of co-engineering nanomaterials and interfacial crosslinking to expand the materials construction and biomedical applications of NC hydrogels in SDT. In this work, mesoporous silica-coated titanium dioxide nanoparticles with thiolated surface functionalization (TiO2@MS-SH) are utilized as crosslinkers to react with norbornene-functionalized dextran (Nor-Dex) through ultrasound-triggered thiol-norbornene reactions, forming TiO2@MS-SH/Nor-Dex NC hydrogels. The TiO2@MS-SH nanoparticles act not only as multivalent crosslinkers to improve the mechanical properties of hydrogels under ultrasound irradiation but also as reactive oxygen species (ROS) generators to allow the use of TiO2@MS-SH/Nor-Dex NC hydrogels in SDT applications. Particularly, the TiO2@MS-SH/Nor-Dex NC hydrogels present tailorable microstructures, properties, and sonodynamic killing of bacteria through the modulation of the ultrasound frequency. Taken together, a versatile TiO2-based NC hydrogel platform prepared under ultrasonic interfacial crosslinking reactions is developed for advancing the applications in SDT.
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Compostos de Sulfidrila , Ultrassom , Nanogéis , Compostos de Sulfidrila/química , Hidrogéis/farmacologia , Hidrogéis/química , Norbornanos/químicaRESUMO
Cancer is a disease with ecological and evolutionary unity, which seriously affects the survival and quality of human beings. Currently, many reports have suggested Gas6 plays an important role in cancer. Binding of gas6 to TAM receptors is associated with the carcinogenetic mechanisms of multiple malignancies, such as in breast cancer, chronic lymphocytic leukemia, non-small cell lung cancer, melanoma, prostate cancer, etc., and shortened overall survival. It is accepted that the Gas6/TAM pathway can promote the malignant transformation of various types of cancer cells. Gas6 has the highest affinity for Axl, an important member of the TAM receptor family. Knockdown of the TAM receptors Axl significantly affects cell cycle progression in tumor cells. Interestingly, Gas6 also has an essential function in the tumor microenvironment. The Gas6/AXL pathway regulates angiogenesis, immune-related molecular markers and the secretion of certain cytokines in the tumor microenvironment, and also modulates the functions of a variety of immune cells. In addition, evidence suggests that the Gas6/AXL pathway is involved in tumor therapy resistance. Recently, multiple studies have begun to explore in depth the importance of the Gas6/AXL pathway as a potential tumor therapeutic target as well as its broad promise in immunotherapy; therefore, a timely review of the characteristics of the Gas6/AXL pathway and its value in tumor treatment strategies is warranted. This comprehensive review assessed the roles of Gas6 and AXL receptors and their associated pathways in carcinogenesis and cancer progression, summarized the impact of Gas6/AXL on the tumor microenvironment, and highlighted the recent research progress on the relationship between Gas6/AXL and cancer drug resistance.