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1.
Opt Express ; 32(5): 7633-7639, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439440

RESUMEN

We present an optical parametric chirped-pulse amplification (OPCPA) based on mixed cascaded crystals, taking advantage of the unique parametric phase-matching of lithium triborate (LiB3O5, LBO) and yttrium calcium oxyborate ((YCa4O(BO3)3, YCOB) crystals. The OPCPA properties of LBO at 880 nm and YCOB at 750 nm are studied respectively. After amplification by two LBO and two YCOB crystals, a total signal gain of 108 and spectral bandwidth close to 400 nm is obtained. After accurate dispersion compensation with a grating-pair compressor and chirped mirror compensator, a pulse duration of 9.4 fs is obtained by a SHG-frequency-resolved optical grating (FROG). This approach will be of great significance in high energy amplifier for high peak power few-cycle laser sources.

2.
Int Wound J ; 21(3): e14495, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37989726

RESUMEN

The effect of diabetes mellitus (DM) on the incidence of postoperative wound complications in patients with coronary artery bypass grafting (CABG) is still unclear. Thus, we performed a meta-analysis of CABG in DM patients to evaluate existing data from both prospective and historical cohorts. The objective of this trial was to assess the relevance and extent of the effect of diabetes on the outcome of previous CABG procedures. Data sources like Embase and Pubmed were found throughout the research, and the language was limited to English through manual search. The searches were performed up to August 2023. The data were extracted from the study of the inclusion/exclusion criteria, the features of the population, the statistical approach and the clinical results. A qualitative evaluation of the qualifying studies has been carried out. Out of the 1874 studies identified, 21 cohort studies were chosen for analysis. Meta-analyses were performed in 258 454 patients (71 351 diabetic and 187 103 non-diabetic). Twenty-one studies on deep sternal wound infections in CABG patients showed a lower rate of deep sternal wound infections in non-diabetes group compared with those with diabetes (OR, 2.13; 95% CI: 1.97, 2.31, p < 0.00001). And 16 studies of superficial wound infections in patients undergoing CABG were found to be associated with a lower rate of superficial injury (OR, 1.93; 95% CI: 1.53, 2.43, p < 0.00001) compared with those with diabetes; In five trials, perfusion time during CABG (MD, 2.31; 95% CI: -0.16, 4.79, p = 0.07) was observed, and there were no significant differences between diabetes and non-diabetes. Currently, there is a higher risk for CABG in diabetes than in non-diabetes patients with sternal infections and superficial injuries. Future randomized trials will concentrate on the treatment of such perioperatively related complications, which will lower the risk of postoperative wound infection in diabetes.

3.
Opt Lett ; 47(21): 5664-5667, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37219298

RESUMEN

We propose a simple single-shot spatiotemporal measurement technique called coherent modulation imaging for the spatio-spectrum (CMISS), which reconstructs the full three-dimensional high-resolution characteristics of ultrashort pulses based on frequency-space division and coherent modulation imaging. We demonstrated it experimentally by measuring the spatiotemporal amplitude and phase of a single pulse with a spatial resolution of 44 µm and a phase accuracy of 0.04 rad. CMISS has good potential for high-power ultrashort-pulse laser facilities and can measure even spatiotemporally complicated pulses with important applications.

4.
Appl Opt ; 60(7): 2056-2061, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690298

RESUMEN

The temporal contrast of ultrashort and ultraintense laser pulses can significantly influence the laser-plasma interactions. As the optical parametric chirped pulse amplification (OPCPA) has been widely adopted in these laser facilities, the inherent optical parametric fluorescence, exhibiting a pedestal in the time window of the pump pulse, has become a significant problem. In this paper, we investigated experimentally its influence on the contrast of the compressed pulses at 808 nm using a multistage OPCPA amplifier. Compared to the highest value of 108 ever reported in the literature for such a type of regime, by adjusting the pump energy allocation between OPCPA stages and controlling the gain of small signal regime, we for the first time, to the best of our knowledge, realized a 1011 temporal contrast in a pure nanosecond OPCPA design at a gain exceeding 7×108, without adopting any other noise cleaning methods, such as picosecond OPCPA, cross-polarized wave generation, etc. This indicates that the OPCPA has a very significant potential for contrast improvement and to become a candidate for the future high-energy amplifiers in ultrashort high-power laser facilities.

5.
Opt Express ; 28(8): 11645-11651, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32403671

RESUMEN

We present a high efficiency and ultra-broadband optical parametric chirped-pulse amplification (OPCPA) system fully based on yttrium calcium oxyborate (YCOB) crystals. The OPCPA properties of YCOB at 808 nm are studied for both high gain and saturated amplification. The non-collinear angle is finely tuned to study the variation of gain spectrum at a certain phase-matching angle of YCOB crystals. After amplification by four YCOB crystals, a total signal gain of 0.9×109 is obtained and the FWHM spectral bandwidth is still over 100 nm. An amplified signal pulse of 182 mJ is achieved with pump energy of 440 mJ in the saturated amplification stage and the conversion efficiency is about 40%. After a four-grating compressor, a pulse duration of 20 fs is measured by a second-order autocorrelator.

6.
Opt Express ; 27(12): 16812-16822, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31252901

RESUMEN

A novel chromatic aberration pre-compensation scheme for ultrashort petawatt laser systems was proposed. The pre-compensation scheme consists of a convex lens, group of concave lenses, and a spherical reflector combined with a conventional vacuum chamber. It provides a versatile method to accurately compensate the chromatic aberration of an entire laser system via controlling the amount of propagation time delay (PTD) induced by the compensator without changing the input and output beam size. A compensator, tailored based on the proposed scheme, was designed and experimentally evaluated for the Shen-Guang-II 5PW (SG-II 5PW) laser system at Shanghai Institute of Optics and Fine Mechanics (SIOM). The experimental results verified that chromatic aberration in the laser system was almost fully compensated: the size of laser beam focused by an f/2.42 off-axis parabolic mirror (OAP) was reduced tremendously from 32×18µm2to about 4×4µm2at full width at half maximum (FWHM). The proposed scheme provides the flexibility to accurately correct chromatic aberration in high-power laser systems within a wide dynamic range.

7.
Mol Pharm ; 16(6): 2315-2325, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31012592

RESUMEN

Rapid intracellular degradation of current drug-delivery nanocarriers presents a challenge for achieving ideal controlled drug-release kinetics. Recent in vivo studies have shown that porous hybrid metal-organic frameworks (MOFs), belonging to the Materials of Institute Lavoisier (MIL) family, display prolonged biodegradation behavior. In this study, we investigated stability of these materials in Kupffer cells, a relevant target for the treatment of several life-threatening immune-mediated liver diseases. For this aim, we selected fluorescently labeled microporous MOF particles of MIL88A and MIL88B-NH2, built from trimers of Fe(III) octahedra, as an inorganic component, and fumarate (MIL88A) or 2-amino terephthalate (MIL88B-NH2), as an organic linker. Cell uptake inhibition analysis of MOF particles by a Kupffer cell line (KUP5) has shown that phagocytosis is the major endocytic pathway involved in MIL88B-NH2 internalization. Investigation of MOF interaction with KUP5 cells by real-time microscopy indicated that the structure of MIL88B-NH2 MOFs stays intact up to 15 min after uptake, followed by MOF accumulation in acidic cell compartments and slow degradation, reaching a minimum of 10-15% decomposition over 24 h. MIL88A particles demonstrated similar degradation kinetics. Analysis of the mechanisms of MOF degradation has shown that inhibition of phagosome acidification as well as protease activity does not prevent decomposition of MIL88B-NH2 particles. Thus, our study demonstrates the relative stability of the MOF structure in the phagolysosomal environment of Kupffer cells, revealing potential use of these materials for controlled drug delivery in a case of immune-mediated liver diseases.


Asunto(s)
Macrófagos del Hígado/metabolismo , Estructuras Metalorgánicas/metabolismo , Citometría de Flujo , Humanos , Cinética , Microscopía
8.
Pharm Res ; 36(4): 53, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30790066

RESUMEN

PURPOSE: Intramacrophagic bacteria pose a great challenge for the treatment of infectious diseases despite many macrophage targeted drug delivery approaches explored. The use of biomimetic approaches for treating infectious diseases is promising, but not studied extensively. The study purpose is to evaluate iron-based metal-organic frameworks (MOF) as a potential bacteria-mimicking delivery system for infectious diseases. METHODS: Two types of carboxylated MOFs, MIL-88A(Fe) and MIL-100(Fe) were developed as "pathogen-like" particles by surface coating with mannose. MOF morphology, cellular uptake kinetics, and endocytic mechanisms in 3D4/21 alveolar macrophages were characterized. RESULTS: MIL-88A(Fe) is rod-shape (aspect ratio 1:5) with a long-axis size of 3628 ± 573 nm and MIL-100(Fe) is spherical with diameter of 103.9 ± 7.2 nm. Cellular uptake kinetics of MOFs showed that MIL-100(Fe) nanoparticles were internalized at a faster rate and higher extent compared to MIL-88A(Fe) microparticles. Mannosylation did not improve the uptake of MIL-100(Fe) particles, whereas it highly increased MIL-88A(Fe) cellular uptake and number of cells involved in internalization. Cell uptake inhibition studies indicated that macropinocytosis/phagocytosis was the main endocytic pathway for internalization of MOFs. Accumulation of MOF particles in acidic compartments was clearly observed. CONCLUSIONS: The successfully synthesized "pathogen-like" particles provide a novel application of MOF-based particles as biomimetic delivery system for intramacrophagic-based infections.


Asunto(s)
Bacterias/metabolismo , Biomimética/métodos , Enfermedades Transmisibles/tratamiento farmacológico , Portadores de Fármacos , Endocitosis , Macrófagos Alveolares/metabolismo , Estructuras Metalorgánicas/metabolismo , Imitación Molecular , Animales , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Antiinfecciosos/metabolismo , Línea Celular , Enfermedades Transmisibles/metabolismo , Hexosaminas/química , Cinética , Manosa/química , Estructuras Metalorgánicas/química , Nanopartículas , Fagocitosis , Pinocitosis , Propiedades de Superficie , Sus scrofa
9.
Opt Lett ; 43(23): 5713-5716, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30499975

RESUMEN

The optical aperture of ultrashort extreme intensity laser facilities, which reach 10 PW, will be beyond several hundred millimeters. DKDP is by now the only nonlinear crystal that can be grown to such diameter and used in the main optical parametric chirped-pulse amplification (OPCPA) amplifier of such a laser system. Here, at the signal wavelength of 808 nm for the first time, we experimentally present a broadband OPCPA system that consists of a pre-amplifier in BBO crystals and a main OPCPA amplifier in two 95% deuterated DKDP crystals. The final amplified spectrum bandwidth exceeds 50 nm, and a compressed pulse duration of 27 fs has been measured. The conversion efficiency of the main OPCPA amplifier reached 24%, and a net signal gain of 13 was obtained. For the high energy OPCPA amplifier, the influence due to partial absorption on the idler pulses in DKDP crystal is theoretically analyzed. The results indicate the potential utilization of high deuterated DKDP for the main OPCPA amplifiers in a multi-petawatt laser system at 808 nm wavelength.

10.
Br J Haematol ; 166(6): 849-61, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24957109

RESUMEN

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.


Asunto(s)
Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos , Linfoma de Células del Manto/tratamiento farmacológico , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Adenina/análogos & derivados , Agammaglobulinemia Tirosina Quinasa , Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Linfoma de Células del Manto/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Fosforilación/efectos de los fármacos , Piperidinas , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , Células Tumorales Cultivadas
11.
Aging (Albany NY) ; 16(2): 1182-1191, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38284891

RESUMEN

OBJECTIVE: Notch-1 is a signal regulatory protein with extensive effects in myeloid cells, but its role in aneurysms remains to be fully clarified. In this study, therefore, the aneurysm mouse model with myeloid-specific knockout of Notch-1 was established to observe the role of Notch-1 in aneurysm progression. METHODS AND RESULTS: The effect of Notch-1 was assessed by pathological staining and Western blotting. It was found that after myeloid-specific knockout of Notch-1 in the aneurysm mouse model, the area of aneurysms and the macrophage infiltration were significantly reduced, the damage to arterial elastic plates was significantly relieved, and the oxidative stress level significantly declined. The results of Western blotting showed that after myeloid-specific knockout of Notch-1, the levels of oxidative stress-related proteins p22 and p47 in aneurysm tissues significantly declined, accompanied by a significant increase in the protein level of Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2). In addition, the levels of phosphorylated myeloid differential protein-88 (MyD88), TIR domain-containing adaptor-inducing interferon-ß (TRIF) and nuclear factor-κB (NF-κB), and inflammatory cytokines interferon-γ (IFN-γ), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) also significantly decreased after myeloid-specific knockout of Notch-1. Following myeloid-specific knockout of Notch-1, the phagocytic capacity of macrophages was enhanced by promoting the SHP2 signaling pathway. CONCLUSION: Notch-1 in monocytes/macrophages can activate the Toll-like receptor (TLR)-mediated inflammatory and stress responses by activating oxidative stress and inhibiting the SHP2 protein expression, thus facilitating aneurysm progression.


Asunto(s)
Aneurisma , Factor 88 de Diferenciación Mieloide , Receptor Notch1 , Animales , Ratones , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Estrés Oxidativo , Transducción de Señal , Receptor Notch1/genética
12.
World J Gastrointest Surg ; 15(5): 953-964, 2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37342843

RESUMEN

BACKGROUND: Gastrointestinal surgery is a complicated process used to treat many gastrointestinal diseases, and it is associated with a large trauma: Most patients often have different degrees of malnutrition and immune dysfunction before surgery and are prone to various infectious complications during postoperative recovery, thus affecting the efficacy of surgical treatment. Therefore, early postoperative nutritional support can provide essential nutritional supply, restore the intestinal barrier and reduce complication occurrence. However, different studies have shown different conclusions. AIM: To assess whether early postoperative nutritional support can improve the nutritional status of patients based on literature search and meta-analysis. METHODS: Articles comparing the effect of early nutritional support and delayed nutritional support were retrieved from PubMed, EMBASE, Springer Link, Ovid, China National Knowledge Infrastructure, China Biology Medicine databases. Notably, only randomized controlled trial articles were retrieved from the databases (from establishment date to October 2022). The risk of bias of the included articles was determined using Cochrane Risk of Bias V2.0. The outcome indicators, such as albumin, prealbumin, and total protein, after statistical intervention were combined. RESULTS: Fourteen literatures with 2145 adult patients undergoing gastrointestinal surgery (1138 patients (53.1%) receiving early postoperative nutritional support and 1007 patients (46.9%) receiving traditional nutritional support or delayed nutritional support) were included in this study. Seven of the 14 studies assessed early enteral nutrition while the other seven studies assessed early oral feeding. Furthermore, six literatures had "some risk of bias," and eight literatures had "low risk". The overall quality of the included studies was good. Meta-analysis showed that patients receiving early nutritional support had slightly higher serum albumin levels, than patients receiving delayed nutritional support [MD (mean difference) = 3.51, 95%CI: -0.05 to 7.07, Z = 1.93, P = 0.05]. Also, patients receiving early nutritional support had shorter hospital stay (MD = -2.29, 95%CI: -2.89 to -1.69), Z = -7.46, P < 0.0001) shorter first defecation time (MD = -1.00, 95%CI: -1.37 to -0.64), Z = -5.42, P < 0.0001), and fewer complications (Odd ratio = 0.61, 95%CI: 0.50 to 0.76, Z = -4.52, P < 0.0001) than patients receiving delayed nutritional support. CONCLUSION: Early enteral nutritional support can slightly shorten the defecation time and overall hospital stay, reduce complication incidence, and accelerate the rehabilitation process of patients undergoing gastrointestinal surgery.

14.
Rev Sci Instrum ; 93(3): 033504, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35364989

RESUMEN

Laser wakefield acceleration (LWFA) using PW-class laser pulses generally requires cm-scale laser-plasma interaction Rayleigh length, which can be realized by focusing such pulses inside a long underdense plasma with a large f-number focusing optic. Here, we present a new PW-based LWFA instrument at the SG-II 5 PW laser facility, which employs f/23 focusing. The setup also adapted an online probing of the plasma density via Nomarski interferometry using a probe laser beam having 30 fs pulse duration. By focusing 1-PW, 30-fs laser pulses down to a focal spot of 230 µm, the peak laser intensity reached a mild-relativistic level of 2.6 × 1018 W/cm2, a level modest for standard LWFA experiments. Despite the large aspect ratio of >25:1 (transverse to longitudinal dimensions) of the laser pulse, electron beams were observed in our experiment only when the laser pulse experienced relativistic self-focusing at high gas-pressure thresholds, corresponding to plasma densities higher than 3 × 1018 cm-3.

15.
Zhongguo Fei Ai Za Zhi ; 13(6): 568-74, 2010 Jun.
Artículo en Zh | MEDLINE | ID: mdl-20681441

RESUMEN

BACKGROUND AND OBJECTIVE: With the ongoing need to improve therapy for lung cancer, there has been an increasing interest in the development of reliable preclinical models to test novel therapeutics. The aim of this study is to establish a patient-derived lung cancer xenograft model in mice and to observe the biological characteristics of xenografts. METHODS: Surgically resected tumor specimens from patients with lung cancer were implanted in the subcutaneous layer of the NOD/ SCID mice. Cancer specimens of percutaneous lung biopsy by CT fluoroscopy were implanted into the subrenal capsule of nude mouse. The subcutaneous carcinoma was surgically removed when it grew to approximately 1.0 cm in diameter, and then re-transplanted into new nude mice. The growth process of transplanted tumor was observed. Expression of CEA, cytokeratin, and Ki67 were detected by immunohistochemistry. Mutations in the exons 18-21 of EGFR and exons 12,59 of K-ras of primary and xenograft tumors were examined. The cell cycle of xenograft tumor cells was analyzed by flow cytometry. RESULTS: Eleven cases were conducted for NOD/SCID mice and nude mice modelling. The patient-derived lung cancer xenografts have been established successfully, and the tumor could be passed to new nude mice, including No 2 model (adenocasinoma), No. 3 model (small cell lung cancer), and No.5 model (squamous cell cancer). High homogeneity was found between xenograft tumors and human lung cancer in histopathology, immunohistochemical phenotype, and EGFR, K-ras mutation status. The S-phase fraction of xenograft cell cycle was prolonged, which indicated that the xenografts remains highly proliferated. CONCLUSION: The xenotransplantation models established for patient-derived lung cancer in immune deficient mice. The success rate is 27%. This model system displayed the biological characteristics of human lung cancer, suggesting that it may provide a stable, reliable, and useful animal model in human lung cancer research.


Asunto(s)
Neoplasias Pulmonares/patología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones SCID , Persona de Mediana Edad , Trasplante de Neoplasias , Trasplante Heterólogo
16.
Immunol Invest ; 38(7): 665-80, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19811429

RESUMEN

OBJECTIVE: The development of immunotherapy for malignancy is greatly limited by the characteristic weak antigenicity of tumors. The primary goal of this study was to circumvent the isolation and purification of tumor-specific antigen determinants by producing a vaccine using lung tumor RNA-loaded dendritic cells (DCs), and to test the response against lung cancer. METHODS: Total RNA was isolated from 18 lung carcinomas with positive carcinoembryonic antigen (CEA) and mucin-1 (MUC1) staining, as identified by immunohistochemistry. DCs and T-cells from peripheral blood mononuclear cells were generated in vitro, and then DCs in different stages were transfected with RNA using several different methods. The expression of CEA and MUC1 in RNA-transfected DCs was measured using flow cytometry. T-cells stimulated by DCs were harvested as effectors, and primary tumor cells cultured in vitro were used as targets. Cytotoxicity was determined by lactic dehydrogenase detection assay. RESULTS: Immature RNA-transfected DCs significantly increased the expression of CEA and MUC1, compared to mature transfected DCs. RNA transfection via electroporation resulted in significantly greater CEA and MUC1 expression than did transfection via lipofection or passive pulsing. Lymphocytes stimulated by DCs transfected with lung tumor RNA initiated a cytotoxic T lymphocyte (CTL) tumor-specific response. CONCLUSION: Immature DCs transfected with total lung carcinoma RNA by electroporation in vitro effectively stimulate antigen-specific CTL responses against tumor cells.


Asunto(s)
Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , ARN Neoplásico/genética , Linfocitos T Citotóxicos/inmunología , Adulto , Anciano , Antígeno Carcinoembrionario/análisis , Antígeno Carcinoembrionario/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia Celular , Citotoxicidad Inmunológica/inmunología , Células Dendríticas/citología , Células Dendríticas/metabolismo , Electroporación , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Inmunofenotipificación , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mucina-1/análisis , Mucina-1/genética , Linfocitos T/citología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Transfección/métodos , Células Tumorales Cultivadas
17.
Cancer Lett ; 265(2): 307-17, 2008 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-18407408

RESUMEN

Somatic mutations in the epidermal growth factor receptor (EGFR) kinase domain are associated with sensitivity to tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC). Our clinical data showed NSCLC patients with exon 19 deletions survived longer following gefitinib treatment than those with exon 21 point mutations. We aimed to investigate whether these two mutations produced differences in phosphorylation of EGFR and downstream signals. Two stable cell lines expressing these mutations were obtained by transfection. Inhibition of phosphorylation of EGFR, Akt, and Erk by gefitinib was detected using Western blotting, and cell inhibition tests were conducted to evaluate the bio-behavior. Gefitinib inhibited the phosphorylation of EGFR, Akt, and Erk to a greater degree in exon 19 deletion cells than in L858R cells. Gefitinib produced G1 arrest in more of the cells with exon 19 deletion than with L858R. This might be attributable to patient selection in TKIs therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Exones , Genes erbB-1 , Quinazolinas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Gefitinib , Humanos , Immunoblotting , Neoplasias Pulmonares , Masculino , Persona de Mediana Edad , Mutación , Inhibidores de Proteínas Quinasas , Estudios Retrospectivos , Transducción de Señal/efectos de los fármacos , Transfección
18.
Blood Adv ; 2(16): 2039-2051, 2018 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-30115641

RESUMEN

The BTK inhibitor ibrutinib has demonstrated a remarkable therapeutic effect in mantle cell lymphoma (MCL). However, approximately one-third of patients do not respond to the drug initially. To identify the mechanisms underlying primary ibrutinib resistance in MCL, we analyzed the transcriptome changes in ibrutinib-sensitive and ibrutinib-resistant cell lines on ibrutinib treatment. We found that MYC gene signature was suppressed by ibrutinib in sensitive but not resistant cell lines. We demonstrated that MYC gene was structurally abnormal and MYC protein was overexpressed in MCL cells. Further, MYC knockdown with RNA interference inhibited cell growth in ibrutinib-sensitive as well as ibrutinib-resistant cells. We explored the possibility of inhibiting MYC through HSP90 inhibition. The chaperon protein is overexpressed in both cell lines and primary MCL cells from the patients. We demonstrated that MYC is a bona fide client of HSP90 in the context of MCL by both immunoprecipitation and chemical precipitation. Furthermore, inhibition of HSP90 using PU-H71 induced apoptosis and caused cell cycle arrest. PU-H71 also demonstrates strong and relatively specific inhibition of the MYC transcriptional program compared with other oncogenic pathways. In a MCL patient-derived xenograft model, the HSP90 inhibitor retards tumor growth and prolongs survival. Last, we showed that PU-H71 induced apoptosis and downregulated MYC protein in MCL cells derived from patients who were clinically resistant to ibrutinib. In conclusion, MYC activity underlies intrinsic resistance to ibrutinib in MCL. As a client protein of HSP90, MYC can be inhibited via PU-H71 to overcome primary ibrutinib resistance.


Asunto(s)
Resistencia a Antineoplásicos , Proteínas HSP90 de Choque Térmico/metabolismo , Linfoma de Células del Manto/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Pirazoles/farmacología , Pirimidinas/farmacología , Adenina/análogos & derivados , Animales , Benzodioxoles/farmacología , Línea Celular Tumoral , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/genética , Humanos , Linfoma de Células del Manto/tratamiento farmacológico , Linfoma de Células del Manto/genética , Linfoma de Células del Manto/patología , Masculino , Ratones , Piperidinas , Proteínas Proto-Oncogénicas c-myc/genética , Purinas/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Cancer Res Clin Oncol ; 133(9): 635-42, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17479290

RESUMEN

PURPOSE: Kinase insert domain-containing receptor (KDR) is one of the molecular targets used in cancer therapy. We studied the KDR expression characteristics and the relationship with the clinical parameters of the patients with lung cancer, to give the basic evidence and clue for tailoring therapy. METHODS: Reverse transcriptase and real-time PCR were used to evaluate the KDR mRNA expression levels in 222 tissue samples (106 tumor tissues, 106 matched normal tissues obtained from the same patients with lung cancer, and 10 normal lung specimens from individuals without lung cancer). The KDR mRNA expression level and clinical parameters were analyzed by paired-sample t test, ANOVA and linear regression, respectively. The Kaplan-Meier method and the log-rank test were used for survival analysis. Expression of KDR protein was also examined immunohistochemically in 15 tumor samples and 15 matched normal lung specimens. RESULTS: The KDR mRNA expression levels were significantly higher in normal tissues (mean 4.50 +/- 0.51) than that in the carcinoma tissues (mean 4.12 +/- 0.50, P < 0.0005). KDR expression in tumor tissues is associated with the histological status, tumor stage, cigarette smoking, and N stage of the patients with lung cancer (P < 0.05) analyzed by using ANOVA methods. Multivariate analysis showed that tumor stages and cigarette smoking status were the two most important independent predictors for the KDR expression levels in tumor tissues (R = 0.415, R (2) = 0.172, F = 10.694, P < 0.0005). Tumors with KDR mRNA expression levels above the mean had a shorter survival (466 +/- 313 days) than did patients with KDR expression levels below the mean (671 +/- 264 days), whereas Kaplan-Meier analysis and log-rank test showed no significant difference in the overall survival between the patients (P = 0.2055). All the 15 normal lung tissues detected showed scale 2 KDR immunostaining. The intensity of immunostaining for KDR in tumor specimens varied from negative (scale 0) to strongest (scale 3) staining. CONCLUSIONS: Locally advanced and non-cigarette smoking patients with lung cancer may be the two valuable surrogate markers for KDR mRNA higher levels. Non-squamous lung cancer, N 2 stage may be the secondary markers for that. The KDR expression level in normal lung tissue is stable, but varied in tumor tissues. Targeting KDR therapy in lung cancer might considerate these clinical and KDR expression information. Further confirmation study must be needed.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Fumar/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Expresión Génica , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Neoplasias Pulmonares/etiología , Persona de Mediana Edad , Estadificación de Neoplasias , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Fumar/efectos adversos , Análisis de Supervivencia
20.
Eur J Pharmacol ; 570(1-3): 175-81, 2007 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-17597605

RESUMEN

The goal of our study was to assess the association between R497K and intron1 (CA) n repeat genetic polymorphisms of the EGF (epidermal growth factor) receptor and the clinical outcome of patients with advanced non-small cell lung cancer treated with EGF receptor tyrosine kinase inhibitor. We determined the genotypes for R497K and intron1 (CA) n repeat genetic polymorphisms of 70 Chinese patients with advanced non-small cell lung cancer. Genetic polymorphisms were correlated with the clinical outcome of treatment with EGF receptor tyrosine kinase inhibitor. In a subgroup of patients whose tumor tissues were available for mutation analysis and IHC (immunohistochemistry) assay, the associations between the EGF receptor mutations, the EGF receptor protein expression levels and EGF receptor polymorphisms were analyzed. The results indicated that patients with a lower number of EGF receptor CA repeats (any allele < or =16 CA) were more likely to have higher EGF receptor protein expression levels, better response, and longer survival time than were patients with a higher number of CA repeats (both alleles >16 CA) after therapy targeted at the EGF receptor (P=0.021; P=0.014; P=0.0392, respectively). In contrast, the R497K polymorphism had no relationship with EGF receptor protein expression levels or the clinical outcome of the patients treated with EGF receptor tyrosine kinase inhibitor (P=0.49; P=0.452, respectively), and there were no associations between the two polymorphisms and somatic mutations (P=0.916; P=0.562, respectively). Overall, our data suggest that the intron1 (CA) n polymorphism of the EGF receptor gene may be associated with the sensitivity to and the prognosis of non-small cell lung cancer after EGF receptor targeted inhibitor treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Quinazolinas/uso terapéutico , Antineoplásicos/efectos adversos , Pueblo Asiatico/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Receptores ErbB/metabolismo , Femenino , Gefitinib , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Mutación , Polimorfismo Genético , Quinazolinas/efectos adversos , Resultado del Tratamiento
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