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1.
J Formos Med Assoc ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38653676

RESUMO

BACKGROUND: /Purpose: The Pediatric Eating Assessment Tool-10 (Pedi-EAT-10) is a caregiver-administrated subjective questionnaire for evaluating swallowing and feeding disorders among children. This study translated the Pedi-EAT-10 into Traditional Chinese and tested the translated version's reliability and validity. METHODS: Pedi-EAT-10 was translated into Traditional Chinese by experts and finalized after discussion and testing. A total of 168 participants, consisting of 32 children with dysphagia from a tertiary medical center and 136 healthy controls from its Children Care Center for Employees, were recruited. All participants were assessed by an otolaryngologist and speech-language pathologist. The reliability, validity, and efficacy of the translated Pedi-EAT-10 were analyzed to ensure it could be used to identify pediatric dysphagia and feeding problems. RESULTS: The Traditional Chinese version of the Pedi-EAT-10 had significant clinical discriminative validity between the dysphagia group and the control group (total score = 9.6 vs. 2.6, P < 0.001), acceptable test-retest reliability (intraclass correlation = 0.63), and excellent internal consistency (Cronbach's α = 0.91 for the entire cohort). The overall performance of the test for distinguishing children with dysphagia from normal controls was acceptable, and the area under the curve was 74.8% (sensitivity = 71.9%; specificity = 69.9%). The optimal cutoff score was ≥3 on the Youdex index. CONCLUSIONS: The Traditional Chinese version of the Pedi-EAT-10 has fair reliability and validity and can be quickly and easily completed by caregivers. The translated Ped-EAT-10 can be used as a first-line tool for assessing the need for further referral and instrumental examination.

2.
Int Wound J ; 21(4): e14758, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629618

RESUMO

A meta-analysis was conducted to comprehensively explore the effects of platelet-rich plasma (PRP) combined with negative pressure wound therapy (NPWT) in treating patients with chronic wounds. Computer searches were conducted, from database infection to November 2023, in EMBASE, Google Scholar, Cochrane Library, PubMed, Wanfang and China National Knowledge Infrastructure databases for randomized controlled trials (RCTs) on the use of PRP combined with NPWT technology for treating chronic wounds. Two researchers independently screened the literature, extracted data and conducted quality assessments according to the inclusion and exclusion criteria. Stata 17.0 software was employed for data analysis. Overall, 18 RCTs involving 1294 patients with chronic wounds were included. The analysis revealed that, compared with NPWT alone, the use of PRP combined with NPWT technology significantly improved the healing rate (odds ratios [OR] = 1.92, 95% confidence intervals [CIs]: 1.43-2.58, p < 0.001) and total effective rate (OR = 1.31, 95% CI: 1.23-1.39, p < 0.001), and also significantly shortened the healing time of the wound (standardized mean difference = -2.01, 95% CI: -2.58 to -1.45, p < 0.001). This study indicates that the treatment of chronic wounds with PRP combined with NPWT technology can significantly enhance clinical repair effectiveness and accelerate wound healing, with a high healing rate, and is worth further promotion and practice.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Plasma Rico em Plaquetas , Humanos , Bandagens , Cicatrização
3.
Macromol Rapid Commun ; 44(1): e2200273, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35583906

RESUMO

Herein, the direct morphological evidence of the extension-induced phase-separated structures in the electrospinning jet observed by high-speed video imaging and by light scattering technique is reported. Model solutions of poly(vinyl alcohol) (PVA)/water are electrospun. Two types of internal structures, that is, long strings and short ellipsoids, are found. A light scattering model is derived for the Vv scattering configuration to account for the scattered intensities contributed from the liquid jet itself and those from the internal structures. For the severely stretching jet of PVA/water, the Vv intensity profile is dominant by the internal structures to mask the scattering contribution from the jet itself. Moreover, the Hv intensity profile reflects the anisotropy of the oriented chains parallel to the jet axis. For the 7 wt% solution, the derived extension rate in the vicinity of the Taylor cone apex is about 3420 s-1 , which is higher than the Rouse relaxation rate measured by rheometer. It is concluded that extension-induced phase separation of the single-phase PVA solution is likely to occur in Taylor-cone apex to trigger the self-assembly process for producing strings (and/or bulges) in the flowing jet, which eventually transform to become the nanofibers, after solvent removal, to be collected on the grounded collector.


Assuntos
Nanofibras , Álcool de Polivinil , Álcool de Polivinil/química , Nanofibras/química , Água/química , Anisotropia
4.
Hum Mol Genet ; 29(9): 1454-1464, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32277753

RESUMO

The mutations in the genes encoding the subunits of complex I of the mitochondrial electron transport chain are the most common cause of Leber's hereditary optic neuropathy (LHON), a maternal hereditary disease characterized by retinal ganglion cell (RGC) degeneration. The characteristics of incomplete penetrance indicate that nuclear genetic and environmental factors also determine phenotypic expression of LHON. Therefore, further understanding of the role of mutant mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit proteins and nuclear genetic factors/environmental effects in the etiology of LHON is needed. In this study, we generated human-induced pluripotent stem cells (hiPSCs) from healthy control, unaffected LHON mutation carrier, and affected LHON patient. hiPSC-derived RGCs were used to study the differences between affected and unaffected carriers of mitochondrial DNA point mutation m.11778G > A in the MT-ND4 gene. We found that both mutated cell lines were characterized by increase in reactive oxygen species production, however, only affected cell line had increased levels of apoptotic cells. We found a significant increase in retrograde mitochondria and a decrease in stationary mitochondria in the affected RGC axons. In addition, the messenger RNA and protein levels of KIF5A in the LHON-affected RGCs were significantly reduced. Antioxidant N-acetyl-L-cysteine could restore the expression of KIF5A and the normal pattern of mitochondrial movement in the affected RGCs. To conclude, we found essential differences in the mutually dependent processes of oxidative stress, mitochondrial transport and apoptosis between two LHON-specific mutation carrier RGC cell lines, asymptomatic carrier and disease-affected, and identified KIF5A as a central modulator of these differences.


Assuntos
Cinesinas/genética , Mitocôndrias/genética , NADH Desidrogenase/genética , Atrofia Óptica Hereditária de Leber/genética , Estresse Oxidativo/genética , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular/efeitos dos fármacos , DNA Mitocondrial/genética , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Atrofia Óptica Hereditária de Leber/metabolismo , Atrofia Óptica Hereditária de Leber/patologia , Mutação Puntual/genética , Espécies Reativas de Oxigênio/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia
5.
Biochem Biophys Res Commun ; 516(3): 983-990, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31272718

RESUMO

Gallbladder carcinoma (GBC) is always diagnosed at an advanced stage, and patients often miss the opportunity for surgery. Gemcitabine (GEM) and platinum-based drugs, including oxaliplatin (OXA), are mainstays of chemotherapy. However, drug resistance causes treatment failure. Hence, salvage mechanisms are critical to improve outcomes. This study revealed the positive correlation between placenta-specific protein 8 (PLAC8) overexpression and PD-L1 overexpression in GBC. Given the roles of PLAC8 and PD-L1 in chemotherapy resistance, GEM-resistant and OXA-resistant cell lines (SGC966GR and SGC966OR, respectively) were established to test whether and how PLAC8 and PD-L1 function in chemotherapy resistance. Drug-insensitive SGC966GR and SGC966OR cells upregulated MRP and MDR1 and had high expression of PLAC8. PLAC8 blockade using siRNA reversed chemotherapy resistance and downregulated MRP and MDR1 in SGC966GR and SGC966OR cells, suggesting that PLAC8 mediates chemotherapy resistance in GBC. Consistent with the increased mRNA levels of PD-L1 after the acquisition of resistance, PLAC8 knockdown reduced PD-L1 mRNA expression in SGC966GR and SGC966OR cells. In conclusion, PLAC8 overexpression in GBC patients positively correlated with PD-L1 expression. PLAC8 conferred resistance to GEM and OXA by upregulating PD-L1 expression, and PLAC8 or PD-L1 blockade may have potential for overcoming chemotherapy resistance, providing therapeutic options for chemotherapy-refractory GBC patients.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/genética , Resistencia a Medicamentos Antineoplásicos/genética , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteínas/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Vesícula Biliar/metabolismo , Vesícula Biliar/patologia , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Oxaliplatina/farmacologia , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Gencitabina
6.
Nanotechnology ; 31(8): 085704, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31689690

RESUMO

Atomistic molecular dynamics simulations are performed to study the thermal stability of bulk superlattices consisting of alkylthiol-coated gold nanocrystals. Using nanocrystals passivated by dodecanethiol chains, we show that the gold superlattice possesses a remarkable high-temperature stability, in agreement with experiment. When heated from room temperature, the superlattice expands slightly at lower temperature (<500 K) and then exhibits a considerable lattice contraction above 500 K, while maintaining the intact crystal structure up to 710 K. Once the temperature increases above 720 K, the gold superlattice becomes structurally unstable due to the local sintering of adjacent nanocrystals. Continuous heating to 750 K drives a large number of gold nanocrystals to coalesce and finally results in a tremendous destruction of the superstructure. The structural change and instability of superlattice are mainly attributed to the ligand desorption from nanocrystal surface induced by the variation in temperature. Furthermore, longer ligand length can effectively improve the thermal stability of gold superlattices. These findings are expected to provide a deep microscopic understanding of the thermal stability of superlattice materials.

7.
J Chem Phys ; 150(3): 034702, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30660164

RESUMO

Atomistic molecular dynamics simulations are performed to study the potential of mean force (PMF) between two asymmetric gold nanocrystals (NCs) capped by alkylthiols in a vacuum. We systematically investigate the dependence of the PMF on the sizes and capping ligand lengths of two NCs. The results show that the potential well depth scales linearly with increasing total length of two capping ligands on asymmetric dimers, but it hardly depends on the NC size. The predicted equilibrium distance between two asymmetric NCs grows significantly and linearly with the total size of two NCs and exhibits only a slight increase with increasing total ligand length. These findings are explained in terms of the amount of ligand interdigitation between NC surfaces as well as its alterations caused by the change in ligand length and NC size. Furthermore, we introduce a simple formula to estimate the equilibrium distance of two asymmetric NCs. On the basis of the computed PMFs, we propose an empirical two-body potential between asymmetric capped gold NCs.

8.
Blood ; 122(16): 2837-47, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23943653

RESUMO

PU-H71 is a purine-scaffold Hsp90 inhibitor that, in contrast to other Hsp90 inhibitors, displays unique selectivity for binding the fraction of Hsp90 that is preferentially associated with oncogenic client proteins and enriched in tumor cells (teHsp90). This property allows PU-H71 to potently suppress teHsp90 without inducing toxicity in normal cells. We found that lymphoma cells infected by Epstein-Barr virus or Kaposi sarcoma-associated herpes virus (KSHV) are exquisitely sensitive to this compound. Using PU-H71 affinity capture and proteomics, an unbiased approach to reveal oncogenic networks, we identified the teHsp90 interactome in KSHV(+) primary effusion lymphoma cells. Viral and cellular proteins were identified, including many involved in nuclear factor (NF)-κB signaling, apoptosis, and autophagy. KSHV vFLIP is a viral oncoprotein homologous to cFLIPs, with NF-κB-activating and antiapoptotic activities. We show that teHsp90 binds vFLIP but not cFLIPs. Treatment with PU-H71 induced degradation of vFLIP and IKKγ, NF-κB downregulation, apoptosis and autophagy in vitro, and more importantly, tumor responses in mice. Analysis of the interactome revealed apoptosis as a central pathway; therefore, we tested a BCL2 family inhibitor in primary effusion lymphoma cells. We found strong activity and synergy with PU-H71. Our findings demonstrate PU-H71 affinity capture identifies actionable networks that may help design rational combinations of effective therapies.


Assuntos
Benzodioxóis/química , Proteínas de Choque Térmico HSP90/metabolismo , Infecções por Herpesviridae/metabolismo , Neoplasias/metabolismo , Neoplasias/virologia , Purinas/química , Proteínas Virais/metabolismo , Animais , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Gammaherpesvirinae , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Camundongos , NF-kappa B/metabolismo , Transplante de Neoplasias , Proteoma , Proteômica/métodos , Transdução de Sinais
9.
Br J Haematol ; 166(6): 849-61, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24957109

RESUMO

Ibrutinib inhibits Bruton tyrosine kinase (BTK), a key component of early B-cell receptor (BCR) signalling pathways. A multicentre phase 2 trial of ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL) demonstrated a remarkable response rate. However, approximately one-third of patients have primary resistance to the drug while other patients appear to lose response and develop secondary resistance. Understanding the molecular mechanisms underlying ibrutinib sensitivity is of paramount importance. In this study, we investigated cell lines and primary MCL cells that display differential sensitivity to ibrutinib. We found that the primary cells display a higher BTK activity than normal B cells and MCL cells show differential sensitivity to BTK inhibition. Genetic knockdown of BTK inhibits the growth, survival and proliferation of ibrutinib-sensitive but not resistant MCL cell lines, suggesting that ibrutinib acts through BTK to produce its anti-tumour activities. Interestingly, inhibition of ERK1/2 and AKT, but not BTK phosphorylation per se, correlates well with cellular response to BTK inhibition in cell lines as well as in primary tumours. Our study suggests that, to prevent primary resistance or to overcome secondary resistance to BTK inhibition, a combinatory strategy that targets multiple components or multiple pathways may represent the most effective approach.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Linfoma de Célula do Manto/tratamento farmacológico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Linfoma de Célula do Manto/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Piperidinas , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Células Tumorais Cultivadas
10.
Cytotherapy ; 16(10): 1371-83, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24996595

RESUMO

BACKGROUND AIMS: The purpose of this study was to examine neurotrophic and neuroprotective effects of limbus stroma-derived mesenchymal stromal cells (L-MSCs) on cortical neurons in vitro and in vivo. METHODS: Cultured L-MSCs were characterized by flow cytometry and immunofluorescence through the use of specific MSC marker antibodies. Conditioned media were collected from normoxia- and hypoxia-treated L-MSCs to assess neurotrophic effects. Neuroprotective potentials were evaluated through the use of in vitro hypoxic cortical neuron culture and in vivo rat focal cerebral ischemia models. Neuronal morphology was confirmed by immunofluorescence with the use of anti-MAP2 antibody. Post-ischemic infarct volume and motor behavior were assayed by means of triphenyltetrazolium chloride staining and open-field testing, respectively. Human growth antibody arrays and enzyme-linked immunoassays were used to analyze trophic/growth factors contained in conditioned media. RESULTS: Isolated human L-MSCs highly expressed CD29, CD90 and CD105 but not CD34 and CD45. Mesenchymal lineage cell surface expression pattern and differentiation capacity were identical to MSCs derived form human bone marrow and adipose tissue. The L-MSC normoxic and hypoxic conditioned media both promoted neurite outgrowth in cultured cortical neurons. Hypoxic conditioned medium showed superior neurotrophic function and neuroprotective potential with reduced ischemic brain injury and improved functional recovery in rat focal cerebral ischemia models. Human growth factor arrays and enzyme-linked immunoassays measurements showed neuroprotective and growth-associated cytokines (vascular endothelial growth factor [VEGF], VEGFR3, brain-derived neurotrophic factor, insulin-like growth factor -2 and hepatocyte growth factor) contained in conditioned media. Hypoxic exposure caused VEGF and brain-derived neurotrophic factor upregulation, possibly contributing to neurotrophic and neuroprotective effects. CONCLUSIONS: L-MSCs can secrete various neurotrophic factors stimulating neurite outgrowth and protecting neurons against brain ischemic injury through paracrine mechanism.


Assuntos
Isquemia Encefálica/terapia , Limbo da Córnea/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Neurogênese , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Humanos , Masculino , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Biomed Pharmacother ; 170: 116006, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091640

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory condition known for its irreversible destructive impact on the joints. Chondrocytes play a pivotal role in the production and maintenance of the cartilage matrix. However, the presence of inflammatory cytokines can hinder chondrocyte proliferation and promote apoptosis. Isoliquiritigenin (ISL), a flavonoid, potentially exerts protective effects against various inflammatory diseases. However, its specific role in regulating the nuclear factor E2-associated factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in chondrocytes in RA remains unclear. To investigate this, this study used human chondrocytes and Sprague-Dawley rats to construct in vitro and in vivo RA models, respectively. The study findings reveal that cytokines markedly induced oxidative stress, the activation of matrix metalloproteinases, and apoptosis both in vitro and in vivo. Notably, ISL treatment significantly mitigated these effects. Moreover, Nrf2 or HO-1 inhibitors reversed the protective effects of ISL, attenuated the expression of Nrf2/HO-1 and peroxisome proliferator-activated receptor gamma-coactivator-1α, and promoted chondrocyte apoptosis. This finding indicates that ISL primarily targets the Nrf2/HO-1 pathway in RA chondrocytes. Moreover, ISL treatment led to improved behavior scores, reduced paw thickness, and mitigated joint damage as well as ameliorated oxidative stress in skeletal muscles in an RA rat model. In conclusion, this study highlights the pivotal role of the Nrf2/HO-1 pathway in the protective effects of ISL and demonstrates the potential of ISL as a treatment option for RA.


Assuntos
Artrite Reumatoide , Heme Oxigenase-1 , Ratos , Humanos , Animais , Heme Oxigenase-1/metabolismo , Condrócitos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-Dawley , Estresse Oxidativo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Citocinas/metabolismo , Apoptose
12.
Blood ; 118(24): 6342-52, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22025527

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, and the role of SYK in its pathogenesis is not completely understood. Using tissue microarray, we demonstrated for the first time that SYK protein is activated in 27 of 61 (44%) primary human DLBCL tissues. Among DLBCL cell lines, 7 were sensitive and 3 were resistant to a highly specific SYK inhibitor, PRT060318. In sensitive DLBCL cells, SYK inhibition blocked the G(1)-S transition and caused cell-cycle arrest. This effect was reproduced by genetic reduction of SYK using siRNA. A detailed analysis of the BCR signaling pathways revealed that the consequence of SYK inhibition on PLCγ2 and AKT, as opposed to ERK1/2, was responsible for cell-cycle arrest. Genetic knock-down of these key molecules decelerated the proliferation of lymphoma cells. In addition, BCR signaling can be blocked by PRT060318 in primary lymphoma cells. Together, these findings provide insights into cellular pathways required for lymphoma cell growth and support the rationale for considering SYK inhibition as a potentially useful therapy for DLBCL. The results further suggest the possibility of using PLCγ2 and AKT as biomarkers to predict therapeutic response in prospective clinical trials of specific SYK inhibitors.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Linfonodos/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosfolipase C gama/antagonistas & inibidores , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Quinase Syk , Células Tumorais Cultivadas
13.
Oncogene ; 42(6): 409-420, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36482202

RESUMO

SHP1, a tyrosine phosphatase, negatively regulates B-cell receptor (BCR) signaling. Ibrutinib selectively inhibits BTK and has been approved for the treatment of several types of B-cell lymphomas, but not yet in diffuse large B-cell lymphoma (DLBCL). A phase 3 clinical trial of ibrutinib-containing regimen has been completed to evaluate its activity in subtypes or subsets of DLBCL patients. Although the subtype of activated B-cell like (ABC) DLBCL is characterized by chronic active BCR signaling, only a fraction of ABC-DLBCL patients seem to benefit from ibrutinib-containing regimen. New alternative predictive biomarkers are needed to identify patients who better respond. We investigated if SHP1 plays a role in defining the level of the BCR activity and impacts the response to ibrutinib. A meta-analysis revealed that lack of SHP1 protein expression as well as SHP1 promoter hypermethylation is strongly associated with NHL including DLBCL. On a tissue microarray of 95 DLBCL samples, no substantial difference in SHP1 expression was found between the GCB and non-GCB subtypes of DLBCL. However, we identified a strong reverse correlation between SHP1 expression and promoter methylation suggesting that promoter hypermethylation is responsible for SHP1 loss. SHP1 knockout in BCR-dependent GCB and ABC cell lines increased BCR signaling activities and sensitize lymphoma cells to the action of ibrutinib. Rescue of SHP1 in the knockout clones, on the other hand, restored BCR signaling and ibrutinib resistance. Further, pharmacological inhibition of SHP1 in both cell lines and patient-derived primary cells demonstrate that SHP1 inhibition synergized with ibrutinib in suppressing tumor cell growth. Thus, SHP1 loss may serve as an alternative biomarker to cell-of-origin to identify patients who potentially benefit from ibrutinib treatment. Our results further suggest that reducing SHP1 pharmacologically may represent a new strategy to augment tumor response to BCR-directed therapies. Schematic diagram summarizing the major findings. Left panel. When SHP1 is present and functional, it negatively regulates the activity of the BCR pathway. Right pane. When SHP1 is diminished or lost, cells depend more on the increased BCR signaling and making them vulnerable to BTK inhibitor, ibrutinib. Diagram was generated using BioRender.


Assuntos
Linfoma Difuso de Grandes Células B , Transdução de Sinais , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linhagem Celular Tumoral , Biomarcadores
14.
Artigo em Inglês | MEDLINE | ID: mdl-37730436

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a heterogenous group of lymphoid malignancies. Based on gene expression profiling, it has been subdivided into germinal center (GC)-derived and activated B-cell (ABC) types. Advances in molecular methodologies have further refined the subclassification of DLBCL, based on recurrent genetic abnormalities. Here, we describe a distinct case of DLBCL that presented in leukemic form. DNA sequencing targeting 275 genes revealed pathogenically relevant mutations of CD79B, MyD88, TP53, TBL1XR1, and PIM1 genes, indicating that this lymphoma would be best classified as MCD/C5 DLBCL, an ABC subtype. Despite an initial good clinical response to BTK inhibitor ibrutinib, anti-CD20 antibody rituxan, alkylating agent bendamustine, and hematopoietic stem-cell transplant, the lymphoma relapsed, accompanied by morphologic and molecular evidence of disease progression. Specifically, the recurrent tumor developed loss of TP53 heterozygosity (LOH) and additional chromosomal changes central to ABC DLBCL pathogenesis, such as PRDM1 loss. Acquired resistance to ibrutinib and rituxan was indicated by the emergence of BTK and FOXO1 mutations, respectively, as well as apparent activation of alternative cell-activation pathways, through copy-number alterations (CNAs), detected by high-resolution chromosomal microarrays. In vitro, studies of relapsed lymphoma cells confirmed resistance to standard BTK inhibitors but sensitivity to vecabrutinib, a noncovalent inhibitor active against both wild-type as well as mutated BTK. In summary, we provide in-depth molecular characterization of a de novo leukemic DLBCL and discuss mechanisms that may have contributed to the lymphoma establishment, progression, and development of drug resistance.


Assuntos
Compostos de Anilina , Linfoma Difuso de Grandes Células B , Recidiva Local de Neoplasia , Piperidinas , Humanos , Rituximab , Genômica , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia
17.
J Phys Condens Matter ; 34(38)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35839749

RESUMO

Molecular dynamics simulations are performed to study the mechanical properties and deformation mechanisms of a heterogeneous face-centered cubic/ body-centered cubic Cu/Ta nanolayered composite under uniaxial tension and compression. The results show that the stress-strain curves exhibit two main yield points in tension while only one yield point during compression, and the deformation primarily experiences three stages. The first stage is linearly elastic at small strains, followed by the nucleation and propagation of dislocations and stacking faults in the Cu layers, and eventually the Ta layers yield to plastic deformation. The yield of the specimen is mainly determined by the dislocation evolution in the hard phase (i.e. Ta layers), which leads to a sharp drop in the stress-strain curve. We show that the heterogeneous nanolayered composite exhibits a good deformation compatibility during compression but an obvious deformation incompatibility between Cu and Ta layers in tension. The temperature effect is also systematically investigated. It is revealed that the yield of the specimen at higher temperature depends only on the dislocation evolution in the thick Ta layers, and the yield strengths in tension and compression both decrease with the increasing temperature. In particular, our computations show that high temperature can significantly suppress the dislocation activities in the Cu layers during deformation, which results in a lower dislocation density of the Cu layers compared with that of the Ta layers and thus causing an incompatible fashion among the constituent layers.

18.
Biomedicines ; 10(3)2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35327514

RESUMO

Cancer-associated fibroblasts (CAFs) are critical for cancer occurrence and progression in the tumor microenvironment (TME), due to their versatile roles in extracellular matrix remodeling, tumor-stroma crosstalk, immunomodulation, and angiogenesis. CAFs are the most abundant stromal component in the TME and undergo epigenetic modification and abnormal signaling cascade activation, such as transforming growth factor-ß (TGF-ß) and Wnt pathways that maintain the distinct phenotype of CAFs, which differs from normal fibroblasts. CAFs have been considered therapeutic targets due to their putative oncogenic functions. Current digestive system cancer treatment strategies often result in lower survival outcomes and fail to prevent cancer progression; therefore, comprehensive characterization of the tumor-promoting and -restraining CAF activities might facilitate the design of new therapeutic approaches. In this review, we summarize the enormous literature on natural compounds that mediate the crosstalk of CAFs with digestive system cancer cells, discuss how the biology and the multifaceted functions of CAFs contribute to cancer progression, and finally, pave the way for CAF-related antitumor therapies.

19.
Front Oncol ; 12: 1008537, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313701

RESUMO

Background: Endoscopic biopsy is the pivotal procedure for the diagnosis of gastric cancer. In this study, we applied whole-slide images (WSIs) of endoscopic gastric biopsy specimens to develop an endoscopic gastric biopsy assistant system (EGBAS). Methods: The EGBAS was trained using 2373 WSIs expertly annotated and internally validated on 245 WSIs. A large-scale, multicenter test dataset of 2003 WSIs was used to externally evaluate EGBAS. Eight pathologists were compared with the EGBAS using a man-machine comparison test dataset. The fully manual performance of the pathologists was also compared with semi-manual performance using EGBAS assistance. Results: The average area under the curve of the EGBAS was 0·979 (0·958-0·990). For the diagnosis of all four categories, the overall accuracy of EGBAS was 86·95%, which was significantly higher than pathologists (P< 0·05). The EGBAS achieved a higher κ score (0·880, very good κ) than junior and senior pathologists (0·641 ± 0·088 and 0·729 ± 0·056). With EGBAS assistance, the overall accuracy (four-tier classification) of the pathologists increased from 66·49 ± 7·73% to 73·83 ± 5·73% (P< 0·05). The length of time for pathologists to manually complete the dataset was 461·44 ± 117·96 minutes; this time was reduced to 305·71 ± 82·43 minutes with EGBAS assistance (P = 0·00). Conclusions: The EGBAS is a promising system for improving the diagnosis ability and reducing the workload of pathologists.

20.
J Urol ; 186(6): 2434-41, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22019170

RESUMO

PURPOSE: Emerging evidence shows that the translocation of apoptosis related factors on cellular organelles, such as mitochondria, endoplasmic reticulum, Golgi apparatus and nucleus, has a crucial role in the apoptotic process. We characterized the effect of paclitaxel (Sigma®) on Golgi involved apoptosis in human hormone refractory prostate cancer. MATERIALS AND METHODS: FACScan™ flow cytometric analysis was used to determine cell cycle distribution and the subG1 (apoptosis) population. Protein expression and localization were detected by Western blot, confocal microscopic examination and the sucrose gradient separation technique. RESULTS: Paclitaxel induced Golgi apparatus disassembly and interaction between Golgi complexes and mitochondria. Discontinuous sucrose gradient fractionation was used to determine and collect Golgi containing fractions. Data revealed that paclitaxel induced an increase of Cdk1 activity and DR5 expression on the Golgi complex that was associated with increased cleavage of caspase-8, a DR5 downstream factor, and caspase-3 into catalytically active fragments. Data were validated by confocal immunofluorescence microscopy. Golgi associated effects were inhibited by the Cdk1 inhibitor roscovitine (Sigma), suggesting a critical role for Golgi-Cdk1. Also, paclitaxel caused an increase of nuclear but not of Golgi associated PKC-δ activity. The selective PKC-δ inhibitor rottlerin (Sigma) completely inhibited the increase of Golgi-Cdk1 activity, suggesting that nuclear PKC-δ served as an upstream regulator of Golgi-Cdk1. CONCLUSIONS: Data suggest that paclitaxel induces nuclear translocation and activation of PKC-δ, which in turn causes Golgi-Cdk1 activation, leading to Golgi associated DR5 up-regulation, and caspase-8 and 3 activation. Golgi mediated signaling cascades facilitate mitochondria involved apoptotic pathways and at least partly explain the anticancer activity of paclitaxel action.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/fisiologia , Paclitaxel/farmacologia , Neoplasias da Próstata/enzimologia , Proteína Quinase C-delta/efeitos dos fármacos , Proteína Quinase C-delta/fisiologia , Complexo de Golgi/enzimologia , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Células Tumorais Cultivadas
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