Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 114
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nat Immunol ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39455893

RESUMO

Tertiary lymphoid structures (TLS) are associated with improved response in solid tumors treated with immune checkpoint blockade, but understanding of the prognostic and predictive value of TLS and the circumstances of their resolution is incomplete. Here we show that in hepatocellular carcinoma treated with neoadjuvant immunotherapy, high intratumoral TLS density at the time of surgery is associated with pathologic response and improved relapse-free survival. In areas of tumor regression, we identify a noncanonical involuted morphology of TLS marked by dispersion of the B cell follicle, persistence of a T cell zone enriched for T cell-mature dendritic cell interactions and increased expression of T cell memory markers. Collectively, these data suggest that TLS can serve as both a prognostic and predictive marker of response to immunotherapy in hepatocellular carcinoma and that late-stage TLS may support T cell memory formation after elimination of a viable tumor.

2.
N Engl J Med ; 387(15): 1373-1384, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36239645

RESUMO

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).


Assuntos
Arteriopatias Oclusivas , Artéria Basilar , Procedimentos Endovasculares , Acidente Vascular Cerebral , Trombectomia , Humanos , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/mortalidade , Arteriopatias Oclusivas/cirurgia , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Isquemia Encefálica/cirurgia , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Fatores de Tempo , Resultado do Tratamento
3.
Plant Physiol ; 194(4): 2101-2116, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37995372

RESUMO

The precise timing of flowering plays a pivotal role in ensuring successful plant reproduction and seed production. This process is intricately governed by complex genetic networks that integrate internal and external signals. This study delved into the regulatory function of microRNA397 (miR397) and its target gene LACCASE-15 (OsLAC15) in modulating flowering traits in rice (Oryza sativa). Overexpression of miR397 led to earlier heading dates, decreased number of leaves on the main stem, and accelerated differentiation of the spikelet meristem. Conversely, overexpression of OsLAC15 resulted in delayed flowering and prolonged vegetative growth. Through biochemical and physiological assays, we uncovered that miR397-OsLAC15 had a profound impact on carbohydrate accumulation and photosynthetic assimilation, consequently enhancing the photosynthetic intensity in miR397-overexpressing rice plants. Notably, we identified that OsLAC15 is at least partially localized within the peroxisome organelle, where it regulates the photorespiration pathway. Moreover, we observed that a high CO2 concentration could rescue the late flowering phenotype in OsLAC15-overexpressing plants. These findings shed valuable insights into the regulatory mechanisms of miR397-OsLAC15 in rice flowering and provided potential strategies for developing crop varieties with early flowering and high-yield traits through genetic breeding.


Assuntos
Oryza , Oryza/metabolismo , Flores/fisiologia , Melhoramento Vegetal , Folhas de Planta/genética , Folhas de Planta/metabolismo , Reprodução , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
4.
J Transl Med ; 22(1): 241, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443917

RESUMO

BACKGROUND: Tumor regression following immune checkpoint blockade (ICB) is often associated with immune-related adverse events (irAEs), marked by inflammation in non-cancerous tissues. This study was undertaken to investigate the functional relationship between anti-tumor and anti-self immunity, to facilitate irAE management while promoting anti-tumor immunity. METHODS: Multiple biopsies from tumor and inflamed tissues were collected from a patient with melanoma experiencing both tumor regression and irAEs on ICB, who underwent rapid autopsy. Immune cells infiltrating melanoma lesions and inflamed normal tissues were subjected to gene expression profiling with multiplex qRT-PCR for 122 candidate genes. Subsequently, immunohistochemistry was conducted to assess the expression of 14 candidate markers of immune cell subsets and checkpoints. TCR-beta sequencing was used to explore T cell clonal repertoires across specimens. RESULTS: While genes involved in MHC I/II antigen presentation, IFN signaling, innate immunity and immunosuppression were abundantly expressed across specimens, irAE tissues over-expressed certain genes associated with immunosuppression (CSF1R, IL10RA, IL27/EBI3, FOXP3, KLRG1, SOCS1, TGFB1), including those in the COX-2/PGE2 pathway (IL1B, PTGER1/EP1 and PTGER4/EP4). Immunohistochemistry revealed similar proportions of immunosuppressive cell subsets and checkpoint molecules across samples. TCRseq did not indicate common TCR repertoires across tumor and inflammation sites, arguing against shared antigen recognition between anti-tumor and anti-self immunity in this patient. CONCLUSIONS: This comprehensive study of a single patient with melanoma experiencing both tumor regression and irAEs on ICB explores the immune landscape across these tissues, revealing similarities between anti-tumor and anti-self immunity. Further, it highlights expression of the COX-2/PGE2 pathway, which is known to be immunosuppressive and potentially mediates ICB resistance. Ongoing clinical trials of COX-2/PGE2 pathway inhibitors targeting the major COX-2 inducer IL-1B, COX-2 itself, or the PGE2 receptors EP2 and EP4 present new opportunities to promote anti-tumor activity, but may also have the potential to enhance the severity of ICB-induced irAEs.


Assuntos
Antígenos de Grupos Sanguíneos , Melanoma , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Inibidores de Checkpoint Imunológico , Ciclo-Oxigenase 2 , Dinoprostona , Inibidores de Ciclo-Oxigenase 2 , Inflamação , Receptores de Antígenos de Linfócitos T
5.
Plant Cell Environ ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39257305

RESUMO

Heat stress at the flowering stage significantly impacts rice grain yield, yet the number of identified genes associated with rice heat tolerance at this crucial stage remains limited. This study focuses on elucidating the function of the heat-induced gene reduced heat stress tolerance 1 (OsRHS). Overexpression of OsRHS leads to reduced heat tolerance, while RNAi silencing or knockout of OsRHS enhances heat tolerance without compromising yield, as assessed by the seed setting rate. OsRHS is localized in the cytoplasm and mainly expressed in the glume and anther of spikelet. Moreover, OsRHS was found to interact with the HSP protein cHSP70-4, and the knockout of cHSP70-4 resulted in increased heat tolerance. Complementation assays revealed that the knockout of cHSP70-4 could restore the compromised heat tolerance in OsRHS overexpression plants. Additional investigation reveals that elevated temperatures can amplify the bond between OsRHS and cHSP70-4 within rice. Furthermore, our findings indicate that under heat stress conditions during the flowering stage, OsRHS plays a negative regulatory role in the expression of many stress-related genes. These findings unveil the crucial involvement of OsRHS and cHSP70-4 in modulating heat tolerance in rice and identify novel target genes for enhancing heat resilience during the flowering phase in rice.

6.
Cereb Cortex ; 33(9): 5493-5500, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36408643

RESUMO

To investigate the dynamic evolution of brain function under the comorbidities of hypertension and aging. Resting-state functional magnetic resonance imaging scans were longitudinally acquired at 10, 24, and 52 weeks in spontaneously hypertensive rats (SHRs) and Wistar-Kyoto rats. We computed the mean amplitude of low-frequency fluctuation (mALFF), mean regional homogeneity (mReHo), and functional connectivity (FC). There was no interaction between hypertension and aging on brain function. The main effect of aging reflects primarily the cumulative increase of brain activity, especially the increase of mALFF in amygdala and mReHo in cingulate cortex, accompanied by the decrease of brain activity. The main effect of hypertension reflects primarily decreased brain activity in default modal network, accompanied by increased brain activity. The main effect of aging shows reduced brain FC as early as 24 weeks, and the main effect of hypertension shows higher brain FC in SHRs. The novel discovery is that 1 brain FC network increased linearly with age in SHRs, in addition to the linearly decreasing FC. Hypertension and aging independently contribute to spatiotemporal alterations in brain function in SHRs following ongoing progression and compensation. This study provides new insight into the dynamic characteristics of brain function.


Assuntos
Hipertensão , Ratos , Animais , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Encéfalo , Envelhecimento , Imageamento por Ressonância Magnética/métodos
7.
Metab Brain Dis ; 38(3): 961-972, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36515797

RESUMO

Parkinson's disease (PD) is an age-related neurodegenerative disease. Long non-coding RNA urothelial carcinoma-associated 1 (UCA1) is involved in the pathogenesis of PD. However, the pathogenesis of PD regulated by UCA1 has not been fully explained. We used 1-Methyl-4-phenylpyridinium (MPP+)-induced SK-N-SH cells for functional analysis. Expression levels of UCA1, microRNA (miR)-671-5p, and KPNA4 (karyopherin subunit alpha 4) mRNA were detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were analyzed using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) or flow cytometry assays. Some protein levels were measured by western blotting. The levels of pro-inflammatory cytokines were tested by ELISA (enzyme-linked immunosorbent assay). The levels of LDH (lactate dehydrogenase), MDA (malondialdehyde), and SOD (superoxide dismutase) were measured using corresponding kits. The relationship between UCA1 or KPNA4 and miR-671-5p was verified by dual-luciferase reporter assay and/or RNA immunoprecipitation (RIP) assay. MPP+ induced UCA1 expression in SK-N-SH cells in a concentration-dependent manner or time-dependent manner. UCA1 knockdown reduced MPP+-induced apoptosis, inflammation, and oxidative stress in SK-N-SH cells. MiR-671-5p was downregulated while KPNA4 was upregulated in MPP+-treated SK-N-SH cells. UCA1 sponged miR-671-5p to regulate KPNA4 expression. MiR-671-5p inhibition counteracted UCA1 knockdown-mediated influence on apoptosis, inflammation, and oxidative stress of MPP+-induced SK-N-SH cells. KPNA4 overexpression offset the inhibitory influence of miR-671-5p mimic on apoptosis, inflammation, and oxidative stress of MPP+-treated SK-N-SH cells. UCA1 inhibition reduced MPP+-induced neuronal damage through the miR-671-5p/KPNA4 pathway in SK-N-SH cells, providing a novel mechanism to understand the pathogenesis of PD.


Assuntos
Carcinoma de Células de Transição , MicroRNAs , Doenças Neurodegenerativas , Doença de Parkinson , RNA Longo não Codificante , Neoplasias da Bexiga Urinária , Humanos , 1-Metil-4-fenilpiridínio/toxicidade , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Doença de Parkinson/genética , Apoptose , alfa Carioferinas
8.
Zhonghua Nan Ke Xue ; 29(6): 562-566, 2023 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38602732

RESUMO

Obstructive azoospermia is a kind of common clinical disease, which often happens in epididymis, vas deferens and ejaculatory duct obstruction and accounts for male infertility. Azoospermia, which is caused by obstruction of the ejaculatory duct, is relatively rare. but the development of endoscopic technology now allows the disease to be resolved by surgery. In the past, transurethral resection of ejaculatory duct (TURED) has been used to treat patients with ejaculatory duct obstruction and azoosperm-free disease. But with the further study of TURED operation in recent years, as well as in patients with postoperative follow-up results showed that the urine - tube reflux and retrograde ejaculation ejaculation the incidence of iatrogenic injury is higherduring the TURED.therefore, in recent years, some experts committed to seeking a less damage and better effect of the surgical method. With the continuous development of endoscopic technology, seminal vesiculoscopy has come into being, which also creates conditions for further understanding the structure and function of the seminal vesicle and distal seminal duct, accurate diagnosis and minimally invasive treatment of the currently discovered diseases. In this article, we summarized the semen abnormalities associated with seminal vesiculoscopy in the treatment of ejaculatory duct obstruction, and also reviewed the surgical methods, clinical application and research progress of seminal vesiculoscopy.


Assuntos
Azoospermia , Ductos Ejaculatórios , Humanos , Masculino , Epididimo , Glândulas Seminais , Ducto Deferente
9.
Appl Opt ; 60(31): 9925-9932, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807182

RESUMO

The binary fused silica gratings (BFSGs) with high diffraction efficiency are presented for large astronomical ground-based telescopes. Calculations demonstrate that the BFSGs could obtain high diffraction efficiency in a wider wavelength range and angle of incident (AOI) range compared with volume phase holographic gratings. Several gratings with a size of 60mm×60mm have been fabricated by holographic lithography and reactive ion-beam etching technology. The measured peak diffraction efficiency reaches 94%, and results show that there are 130 nm wavelength bandwidth and 12° AOI bandwidth in which diffraction efficiency is higher than 70%. The stray light causes the diffraction efficiency to decrease by about 0.48%. All measurements have indicated good consistency with the simulation results.

10.
Sensors (Basel) ; 21(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34073999

RESUMO

With the advanced development of the intelligent transportation system, vehicular ad hoc networks have been observed as an excellent technology for the development of intelligent traffic management in smart cities. Recently, researchers and industries have paid great attention to the smart road-tolling system. However, it is still a challenging task to ensure geographical location privacy of vehicles and prevent improper behavior of drivers at the same time. In this paper, a reliable road-tolling system with trustworthiness evaluation is proposed, which guarantees that vehicle location privacy is secure and prevents malicious vehicles from tolling violations at the same time. Vehicle route privacy information is encrypted and uploaded to nearby roadside units, which then forward it to the traffic control center for tolling. The traffic control center can compare data collected by roadside units and video surveillance cameras to analyze whether malicious vehicles have behaved incorrectly. Moreover, a trustworthiness evaluation is applied to comprehensively evaluate the multiple attributes of the vehicle to prevent improper behavior. Finally, security analysis and experimental simulation results show that the proposed scheme has better robustness compared with existing approaches.

11.
Zhonghua Nan Ke Xue ; 27(12): 1119-1123, 2021 Dec.
Artigo em Zh | MEDLINE | ID: mdl-37454323

RESUMO

With the increasing awareness of men's health, more and more clinical studies are reported on the relationship of testicular microlithiasis (TM) with male infertility. TM is a relatively rare disease characterized by multiple microcalcifications (<3 mm) in the seminiferous tubules of the testis. This review summarizes the findings in the studies of the diagnosis, epidemiology, correlation with male fertility, treatment, and follow-up of TM in recent years. Many researches show that TM has a certain correlation with the decline of male fertility, which, however, is not identically agreed on at home and abroad. As for the treatment of TM complicated with male infertility, there is still a lack of effective and reliable drugs and strategies and a need for many basic and clinical studies.

12.
Gastroenterology ; 157(3): 838-850.e6, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31163177

RESUMO

BACKGROUND & AIMS: Little is known about mechanisms of perineural invasion (PNI) by pancreatic ductal adenocarcinomas (PDAs) or other tumors. Annexin A2 (ANXA2) regulates secretion of SEMA3D, an axon guidance molecule, which binds and activates the receptor PLXND1 to promote PDA invasion and metastasis. We investigated whether axon guidance molecules promote PNI and metastasis by PDA cells in mice. METHODS: We performed studies in a dorsal root ganglion (DRG) invasion system, wild-type C57BL/6 mice (controls), mice with peripheral sensory neuron-specific disruption of PlxnD1 (PLAC mice), LSL-KRASG12D/+;LSL-TP53R172H/+;PDX-1-CRE+/+ (KPC) mice, and KPC mice crossed with ANXA2-knockout mice (KPCA mice). PDA cells were isolated from KPC mice and DRG cells were isolated from control mice. Levels of SEMA3D or ANXA2 were knocked down in PDA cells with small hairpin and interfering RNAs and cells were analyzed by immunoblots in migration assays, with DRGs and with or without antibodies against PLXND1. PDA cells were injected into the pancreas of control and PLAC mice, growth of tumors was assessed, and tumor samples were analyzed by histology. DRG cells were incubated with SEMA3D and analyzed by live imaging. We measured levels of SEMA3D and PLXND1 in PDA specimens from patients with PNI and calculated distances between tumor cells and nerves. RESULTS: DRG cells increase the migration of PDC cells in invasion assays; knockdown of SEMA3D in PDA cells or antibody blockade of PLXND1 on DRG cells reduced this invasive activity. In mice, orthotopic tumors grown from PDA cells with knockdown of SEMA3D, and in PLAC mice, orthotopic tumors grown from PDA cells, had reduced innervation and formed fewer metastases than orthotopic tumors grown from PDA cells in control mice. Increased levels of SEMA3D and PLXND1 in human PDA specimens associated with PNI. CONCLUSIONS: DRG cells increase the migratory and invasive activities of pancreatic cancer cells, via secretion of SEMA3D by pancreatic cells and activation of PLXND1 on DRGs. Knockdown of SEMA3D and loss of neural PLXND1 reduces innervation of orthotopic PDAs and metastasis in mice. Increased levels of SEMA3D and PLXND1 in human PDA specimens associated with PNI. Strategies to disrupt the axon guidance pathway mediated by SEMA3D and PLXND1 might be developed to slow progression of PDA.


Assuntos
Anexina A2/metabolismo , Orientação de Axônios , Carcinoma Ductal Pancreático/metabolismo , Movimento Celular , Gânglios Espinais/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/metabolismo , Semaforinas/metabolismo , Animais , Anexina A2/deficiência , Anexina A2/genética , Orientação de Axônios/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/secundário , Comunicação Celular , Gânglios Espinais/patologia , Regulação Neoplásica da Expressão Gênica , Genes p53 , Genes ras , Predisposição Genética para Doença , Proteínas de Homeodomínio/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Invasividade Neoplásica , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Crescimento Neuronal , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Semaforinas/genética , Transdução de Sinais , Transativadores/genética , Células Tumorais Cultivadas
13.
Mod Pathol ; 33(10): 2026-2034, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32457408

RESUMO

Neoadjuvant chemotherapy (NAC) is often the treatment of choice for borderline resectable and locally advanced invasive pancreatic ductal adenocarcinoma (PDAC); however, most cancers only partially respond to therapy. We hypothesized that the location of residual neoplastic cells in resected specimens following NAC could provide a clue as to the mechanisms of resistance. PDAC cells invade the stroma but can also invade back into and spread via the pancreatic ducts, which has been referred to as "cancerization of ducts" (COD). We compared the responsiveness to chemotherapy between PDAC cells in the stroma and PDAC cells in the duct. Pancreatic resections from a total of 174 PDAC patients (NAC, n = 97; immediate surgery, n = 77) were reviewed. On hematoxylin and eosin sections, COD was identified at the same prevalence in both groups (NAC: 50/97 cases, 52%; immediate surgery: 39/77 cases, 51%; p = 0.879, Fisher's exact test). However, using quantitative image analysis of CK19 immunohistochemistry, we found that the proportion of cancer cells that were intraductal was significantly different between the NAC and immediate surgery groups (median; 12.7% vs. 1.99%, p < 0.0001, Mann-Whitney U test). This proportion was highest in patients with marked therapy responses (36.2%) compared with patients with moderate or poor responses (7.21 & 7.91%). In summary, our data suggest that intraductal components in PDAC are less responsive to chemotherapy than the remainder of the tumor, which could have important implications for therapeutic resistance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Pancreáticas
14.
Stem Cells ; 37(3): 306-317, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30471152

RESUMO

Directed differentiation of human induced pluripotent stem cells (iPSCs) toward hepatobiliary lineages has been increasingly used as models of human liver development/diseases. As protein kinases are important components of signaling pathways regulating cell fate changes, we sought to define the key molecular mediators regulating human liver development using inhibitors targeting tyrosine kinases during hepatic differentiation of human iPSCs. A library of tyrosine kinase inhibitors was used for initial screening during the multistage differentiation of human iPSCs to hepatic lineage. Among the 80 kinase inhibitors tested, only Src inhibitors suppressed endoderm formation while none had significant effect on later stages of hepatic differentiation. Transient inhibition of c-Src during endodermal induction of human iPSCs reduced endodermal commitment and expression of endodermal markers, including SOX17 and FOXA2, in a dose-dependent manner. Interestingly, the transiently treated cells later developed into profibrogenic cholangiocyte-like cells expressing both cholangiocyte markers, such as CK7 and CK19, and fibrosis markers, including Collagen1 and smooth muscle actin. Further analysis of these cells revealed colocalized expression of collagen and yes-associated protein (YAP; a marker associated with bile duct proliferation/fibrosis) and an increased production of interleukin-6 and tumor necrosis factor-α. Moreover, treatment with verteporfin, a YAP inhibitor, significantly reduced expression of fibrosis markers. In summary, these results suggest that c-Src has a critical role in cell fate determination during endodermal commitment of human iPSCs, and its alteration in early liver development in human may lead to increased production of abnormal YAP expressing profibrogenic proinflammatory cholangiocytes, similar to those seen in livers of patients with biliary fibrosis. Stem Cells 2019;37:306-317.


Assuntos
Proteína Tirosina Quinase CSK/antagonistas & inibidores , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Endoderma/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Ductos Biliares/enzimologia , Ductos Biliares/patologia , Proteína Tirosina Quinase CSK/metabolismo , Endoderma/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/enzimologia , Células-Tronco Pluripotentes Induzidas/patologia , Fígado/enzimologia , Fígado/patologia
15.
J Pediatr Gastroenterol Nutr ; 69(3): 344-350, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31436671

RESUMO

INTRODUCTION: Biliary atresia (BA) is characterized by rapidly progressive inflammation and fibrosis of the biliary tract, which usually progresses despite surgical intervention (Kasai hepatoportoenterostomy). Lysyl oxidase-like (LOXL2) is an extracellular matrix enzyme that catalyzes the cross-linking of fibrillar collagen and elastin and is thought to play a crucial role in tissue fibrosis; anti-LOXL2 drugs have been shown to be antifibrotic in animals. OBJECTIVE: The aim of the study was to investigate the presence of LOXL2 in BA livers and hepatic and extrahepatic control tissues. METHODS: Liver wedge biopsies from infants with BA (n = 20) were obtained at Kasai, and were compared with non-BA livers (n = 20). Liver fibrosis was scored using the Ishak scale, and immunohistochemistry was performed using a commercially available polyclonal anti-LOXL2 antibody. The expression of LOXL2 was scored for intensity and for distribution of bile duct staining by a pathologist blinded to the diagnosis. Staining of LOXL2 in pediatric control tissue, muscle (n = 5), heart (n = 5), and bone (n = 10) was performed. RESULTS: Tissue from patients with BA abundantly expressed LOXL2 (intensity score 2.0 vs 1.4 [P ≤ 0.001]) for non-BA and distribution of bile duct-staining score of 3.0 versus 2.8 (P = 0.001) for non-BA. Fibrosis score of all BA samples was 4.2 versus 3.1 for non-BA. Nonhepatic pediatric tissue displayed minimal to no LOXL2 staining. CONCLUSIONS: There is significant overexpression of LOXL2 in BA hepatic tissue with minimal expression in extrahepatic tissue. The over expression noted in human hepatic tissue at Kasai suggests the rationale for further investigation of anti-LOXL2 therapeutics in BA.


Assuntos
Aminoácido Oxirredutases/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Atresia Biliar/metabolismo , Adolescente , Atresia Biliar/patologia , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Masculino , Projetos Piloto , Bancos de Tecidos , Adulto Jovem
16.
Proc Natl Acad Sci U S A ; 112(5): 1428-33, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25605895

RESUMO

Current approaches to cancer treatment focus on targeting signal transduction pathways. Here, we develop an alternative system for targeting cell mechanics for the discovery of novel therapeutics. We designed a live-cell, high-throughput chemical screen to identify mechanical modulators. We characterized 4-hydroxyacetophenone (4-HAP), which enhances the cortical localization of the mechanoenzyme myosin II, independent of myosin heavy-chain phosphorylation, thus increasing cellular cortical tension. To shift cell mechanics, 4-HAP requires myosin II, including its full power stroke, specifically activating human myosin IIB (MYH10) and human myosin IIC (MYH14), but not human myosin IIA (MYH9). We further demonstrated that invasive pancreatic cancer cells are more deformable than normal pancreatic ductal epithelial cells, a mechanical profile that was partially corrected with 4-HAP, which also decreased the invasion and migration of these cancer cells. Overall, 4-HAP modifies nonmuscle myosin II-based cell mechanics across phylogeny and disease states and provides proof of concept that cell mechanics offer a rich drug target space, allowing for possible corrective modulation of tumor cell behavior.


Assuntos
Miosina Tipo II/efeitos dos fármacos , Acetofenonas/farmacologia , Carbamatos/farmacologia , Células HEK293 , Células HL-60 , Humanos , Miosina Tipo II/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Células Tumorais Cultivadas
17.
BMC Plant Biol ; 17(1): 206, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29157222

RESUMO

BACKGROUND: A recently discovered tea [Camellia sinensis (L.) O. Kuntze] cultivar can generate tender shoots in winter. We performed comparative proteomics to analyze the differentially accumulated proteins between winter and spring tender shoots of this clonal cultivar to reveal the physiological basis of its evergrowing character during winter. RESULTS: We extracted proteins from the winter and spring tender shoots (newly formed two leaves and a bud) of the evergrowing tea cultivar "Dongcha11" respectively. Thirty-three differentially accumulated high-confidence proteins were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF / TOF MS). Among these, 24 proteins had increased abundance while nine showed were decreased abundance in winter tender shoots as compared with the spring tender shoots. We categorized the differentially accumulated proteins into eight critical biological processes based on protein function annotation including photosynthesis, cell structure, protein synthesis & destination, transporters, metabolism of sugars and polysaccharides, secondary metabolism, disease/defense and proteins with unknown functions. Proteins with increased abundance in winter tender shoots were mainly related to the processes of photosynthesis, cytoskeleton and protein synthesis, whereas those with decreased abundance were correlated to metabolism and the secondary metabolism of polyphenolic flavonoids. Biochemical analysis showed that the total contents of soluble sugar and amino acid were higher in winter tender shoots while tea polyphenols were lower as compared with spring tender shoots. CONCLUSIONS: Our study suggested that the simultaneous increase in the abundance of photosynthesis-related proteins rubisco, plastocyanin, and ATP synthase delta chain, metabolism-related proteins eIF4 and protease subunits, and the cytoskeleton-structure associated proteins phosphatidylinositol transfer protein and profilin may be because of the adaptation of the evergrowing tea cultivar "Dongcha11" to low temperature and light conditions. Histone H4, Histone H2A.1, putative In2.1 protein and protein lin-28 homologs may also regulate the development of winter shoots and their response to adverse conditions.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Proteômica/métodos , Camellia sinensis/fisiologia , Eletroforese em Gel Bidimensional , Luz , Espectrometria de Massas , Fotossíntese/fisiologia , Proteínas de Plantas/análise , Proteínas de Plantas/fisiologia , Brotos de Planta/química , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Temperatura
18.
Yao Xue Xue Bao ; 52(3): 416-24, 2017 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29979850

RESUMO

This study was conducted to design and synthetize highly efficient, specific, non-resistant small MEK inhibitors. Based on active small molecules which have been reported, we studied the action mode with MEK protein using Autodock 4.2, generated innovative and feasible design method, designed novel small MEK protein inhibitors with a reference to molecular modeling and docking. The anti-tumor activities of four kinds of cells including MCF-7, PANC-1, SY5Y, A549 were tested with MTT method in vitro. The structure of 10 new small molecules has been determined with 1H NMR and 13C NMR. The compounds 4, 6, 7, 8, 10 had high antitumor activities, the compounds 1, 3, 5 also showed good activity, and the compounds 2, 9 showed cell selectivity in killing tumor.


Assuntos
Antineoplásicos/química , Desenho de Fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
19.
Am J Physiol Gastrointest Liver Physiol ; 311(3): G396-411, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27229120

RESUMO

The Hippo pathway effector Yes-associated protein (YAP) regulates liver size by promoting cell proliferation and inhibiting apoptosis. However, recent in vivo studies suggest that YAP has important cellular functions other than controlling proliferation and apoptosis. Transgenic YAP expression in mouse hepatocytes results in severe jaundice. A possible explanation for the jaundice could be defects in adherens junctions that prevent bile from leaking into the blood stream. Indeed, immunostaining of E-cadherin and electron microscopic examination of bile canaliculi of Yap transgenic livers revealed abnormal adherens junction structures. Using primary hepatocytes from Yap transgenic livers and Yap knockout livers, we found that YAP antagonizes E-cadherin-mediated cell-cell junction assembly by regulating the cellular actin architecture, including its mechanical properties (elasticity and cortical tension). Mechanistically, we found that YAP promoted contractile actin structure formation by upregulating nonmuscle myosin light chain expression and cellular ATP generation. Thus, by modulating actomyosin organization, YAP may influence many actomyosin-dependent cellular characteristics, including adhesion, membrane protrusion, spreading, morphology, and cortical tension and elasticity, which in turn determine cell differentiation and tissue morphogenesis.


Assuntos
Citoesqueleto de Actina/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Junções Aderentes/fisiologia , Hepatócitos/fisiologia , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Caderinas , Proteínas de Ciclo Celular , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fosfoproteínas/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
20.
Ann Surg Oncol ; 23(8): 2610-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27012989

RESUMO

BACKGROUND: Program death 1 (PD-1) and its ligand (PD-L1) have been identified as potential therapeutic targets for solid and hematologic malignancies. The current study aimed to assess PD-L1 expression in intrahepatic cholangiocarcinoma (ICC) and relate clinical outcomes to its expression. METHODS: Formalin-fixed, paraffin-embedded tumor specimens were obtained for patients undergoing surgery at Johns Hopkins Hospital between 1991 and 2011. Immunohistochemistry was used to assess PD-L1 expression in tumor-associated macrophages (TAMs) and within the tumor front (TF). RESULTS: Of 54 tumor samples analyzed, 34 stained positive for PD-L1 expression on TAMs (TAMs+), and 39 stained positive for PD-L1 expression on cells within the tumor front (TF+). The TF+ patients were less likely to present with metastatic lymph nodes (N1 patients: 26.7 vs 7.7 %; p = 0.011), whereas all tumors with intrahepatic metastasis failed to demonstrate staining for PD-L1 around the tumor front (p = 0.020). Patients with tumors shown to be TAMs+ were less likely to present with multiple lesions (35.0 vs 8.8 %; p = 0.017). Patients with tumors exhibiting PD-L1 expression around the tumor front demonstrated a worse overall survival than TF patients (p = 0.008). Multivariable analysis showed that patients with tumors staining for PD-L1 in the tumor front had a 59.5 % reduced survival (TF- vs TF+: time ratio, 0.405; 95 % confidence interval, 0.215-0.761; p = 0.005). CONCLUSION: Expression of PD-L1 was noted among a majority of patients, and PD-L1 expression within the tumor front was associated with a 60 % decreased survival. Future clinical trials are necessary to assess the safety and efficacy of anti-PD-L1 therapies among patients with ICC.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias dos Ductos Biliares/patologia , Biomarcadores Tumorais/metabolismo , Colangiocarcinoma/patologia , Recidiva Local de Neoplasia/patologia , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/cirurgia , Pontos de Checagem do Ciclo Celular , Colangiocarcinoma/metabolismo , Colangiocarcinoma/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Taxa de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA