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1.
BMC Biol ; 21(1): 64, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37069598

RESUMEN

BACKGROUND: Among six extant tiger subspecies, the South China tiger (Panthera tigris amoyensis) once was widely distributed but is now the rarest one and extinct in the wild. All living South China tigers are descendants of only two male and four female wild-caught tigers and they survive solely in zoos after 60 years of effective conservation efforts. Inbreeding depression and hybridization with other tiger subspecies were believed to have occurred within the small, captive South China tiger population. It is therefore urgently needed to examine the genomic landscape of existing genetic variation among the South China tigers. RESULTS: In this study, we assembled a high-quality chromosome-level genome using long-read sequences and re-sequenced 29 high-depth genomes of the South China tigers. By combining and comparing our data with the other 40 genomes of six tiger subspecies, we identified two significantly differentiated genomic lineages among the South China tigers, which harbored some rare genetic variants introgressed from other tiger subspecies and thus maintained a moderate genetic diversity. We noticed that the South China tiger had higher FROH values for longer runs of homozygosity (ROH > 1 Mb), an indication of recent inbreeding/founder events. We also observed that the South China tiger had the least frequent homozygous genotypes of both high- and moderate-impact deleterious mutations, and lower mutation loads than both Amur and Sumatran tigers. Altogether, our analyses indicated an effective genetic purging of deleterious mutations in homozygous states from the South China tiger, following its population contraction with a controlled increase in inbreeding based on its pedigree records. CONCLUSIONS: The identification of two unique founder/genomic lineages coupled with active genetic purging of deleterious mutations in homozygous states and the genomic resources generated in our study pave the way for a genomics-informed conservation, following the real-time monitoring and rational exchange of reproductive South China tigers among zoos.


Asunto(s)
Tigres , Animales , Femenino , Masculino , Tigres/genética , Metagenómica , Genoma , Genómica , China , Conservación de los Recursos Naturales
2.
Mol Carcinog ; 62(2): 135-144, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36239572

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer that lacks targeted therapies. Previous studies have shown that TNBC cells are highly sensitive to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), making it a promising agent for treating TNBC. However, the development of TRAIL resistance limits its further clinical development, and the underlying mechanisms are not fully understood. In this study, we report the role of PD-L1 in TRAIL resistance. Specifically, we found that TRAIL treatment increases PD-L1 expression in TRAIL-sensitive cells and that basal PD-L1 expression is increased in acquired TRAIL-resistant cells. Mechanistically, we found that increased PD-L1 expression was accompanied by increased extracellular signal-regulated kinase (ERK) activation. Using both genetic and pharmacological approaches, we showed that knockdown of ERK by siRNA or inhibition of ERK activation by the mitogen-activated protein kinase kinase inhibitor U0126 decreased PD-L1 expression and increased TRAIL-induced cell death. Furthermore, we found that knockout or knockdown of PD-L1 enhances TRAIL-induced apoptosis, suggesting that PD-L1-mediated TRAIL resistance is independent of its ability to evade immune suppression. Therefore, this study identifies a noncanonical mechanism by which PD-L1 promotes TRAIL resistance, which can be potentially exploited for immune checkpoint therapy.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Antígeno B7-H1/genética , Apoptosis , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Línea Celular Tumoral
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(1): 149-153, 2022 Jan.
Artículo en Zh | MEDLINE | ID: mdl-35048616

RESUMEN

OBJECTIVE: To study the sleep electroencephalogram (EEG) power features of patients with chronic insomnia. METHODS: Retrospective analysis was performed with patients who met the ICD-10 diagnostic criteria for chronic insomnia, using polysomnography (PSG) to examine the overnight sleep EEG. The sleep architectures and relative EEG power across five frequency bands during overnight sleep were compared to study the differences between the insomnia and control groups. Furthermore, the correlation between EEG power and various PSG measures was also analyzed. RESULTS: Forty-five subjects were enrolled in the study, including 25 chronic insomniacs (18 females, aged [36.2±10.7] years) and 20 controls (18 females, aged [36.1±7.6] years). Compared to those of the control group, insomnia patients had significantly lower value of delta power ([38.0±6.1] vs. [43.2±5.8], P<0.05) in the NREM1 stage, and increased value of beta power during total NREM, NREM1 and NREM2 (NREM sleep [5.4±2.3] vs. [3.8±1.4], NREM1 [11.3±3.5] vs. [8.7±2.8], and NREM2 [5.7±2.3] vs. [4.4±1.4], all P<0.05). For correlation analyses, in the insomnia group, a significantly positive correlation was found between the delta value during NREM sleep and the duration of NREM3 sleep ( r=0.527). The beta value during NREM sleep was found to be negatively correlated to the duration of NREM3 sleep ( r=-0.767). A positive correlation was found between the beta value during NREM sleep and the duration of NREM1 and NREM2 sleep ( r=0.486 and 0.589, respectively). CONCLUSION: The results suggest that patients with chronic insomnia have decreased low-frequency EEG power, but increased high-frequency EEG power during NREM sleep. The findings indicate that cortex arousal level is elevated in chronic insomniacs during NREM sleep.


Asunto(s)
Trastornos del Inicio y del Mantenimiento del Sueño , Anciano , Electroencefalografía , Femenino , Humanos , Polisomnografía , Estudios Retrospectivos , Sueño
4.
Antonie Van Leeuwenhoek ; 113(9): 1385-1391, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32656718

RESUMEN

The purpose of this study was to culture and characterise bacteria from an intact abscess on the skin of a dead Bryde's whale (Balaenoptera edeni) which stranded in the northern Beibu Gulf, China. To grow bacteria, samples from the abscess were added to blood agar. After incubation, yellowish mucous colonies were visualized. The bacterium was firstly recognised as Shewanella algae by the VITEK® 2 System. However, by using 16S rRNA gene sequencing the bacterium was finally identified as S. indica. To characterise the bacterium, antibiotic susceptibility and virulence factors, such as hemolysis and biofilm formation were investigated. The bacterium is capable of ß-hemolysis and biofilm formation and it is also sensitive to several different classes of antibiotics, such as ß-lactams, quinolones, and aminoglycosides. To date there have been no reports of this bacterium causing infections in humans or animals. However, in this study we described the first case of S. indica isolated from an intact abscess on the back of a Bryde's whale.


Asunto(s)
Balaenoptera/microbiología , Filogenia , Shewanella/clasificación , Animales , Proteínas Bacterianas/análisis , Técnicas de Tipificación Bacteriana , Biopelículas/crecimiento & desarrollo , China , ADN Bacteriano/genética , Proteínas Hemolisinas/análisis , Pruebas de Sensibilidad Microbiana , ARN Ribosómico 16S/genética , Shewanella/aislamiento & purificación
5.
J Med Virol ; 88(1): 13-20, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26104380

RESUMEN

Chronic hepatitis B virus (HBV) infection is the result of an inadequate immune response towards the virus. Dendritic cells (DCs), as the most efficient professional antigen-presenting cells (APCs), possess the strongest antigen presenting the effect in the body and can stimulate the initial T cell activation and proliferation. DCs of patients with chronic HBV infection are impaired, resulting in more tolerogenic rather than immunogenic responses, which may contribute to viral persistence. Recently, numerous methods have been developed to induce DCs maturation. To date, recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) combined with interleukin-4 (rhIL-4) has been a classic culture combination to DCs. The recently classified type III interferon group interferon-λ (IFN-λ) displays antiviral, antitumor, and immunoregulatory activity. In our laboratory, we demonstrate that IFN-λ1 combined with rhGM-CSF and rhIL-4 can significantly increase the expression of DC surface molecules and the secretion of interleukin-12 (IL-12) and interferon-γ (IFN-γ) in patients with chronic hepatitis B infection. In this review, we emphasize on the role of DCs in the immunopathogenesis of chronic HBV infection. Importantly, we systematic review that the latest update in the current status of knowledge on the methods of inducing DCs maturation in anti-HBV immunity. What's more, we conclude that IFN-λ1 combined with GM-CSF and IL-4 can induce DCs maturation, which could become a possibility to be applied to the autologus dendritic cell vaccine to treat chronic hepatitis B.


Asunto(s)
Células Dendríticas/inmunología , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/patología , Tolerancia Inmunológica , Hepatitis B Crónica/terapia , Interacciones Huésped-Patógeno , Humanos , Factores Inmunológicos/uso terapéutico
6.
Alcohol Alcohol ; 51(3): 251-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26511776

RESUMEN

AIMS: Ceramide is an important second messenger in the sphingomyelin signaling pathway. In this review, we will focus on the potential role of ceramide in the pathogenesis of alcoholic liver disease (ALD). METHODS: We have summarized the relevant studies and reviews about the role of ceramide in ALD. In addition, we have discussed the role of acid sphingomyelinase and protein phosphatase 2A in ALD, which are associated with ceramide and hepatic steatosis. RESULTS: Recent studies have proved that the immunoreactivity and content of ceramide were increased, both in experimental models of chronic alcohol-induced steatohepatitis and human livers with severe chronic alcohol-related liver disease. Consistent with that, the levels of protein phosphatase 2A and acid sphingomyelinase were increased. Of relevance, the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) was inhibited, which could block the fatty acid oxidation and promote its synthesis. CONCLUSIONS: It was hypothesized that ethanol promoted ceramide accumulation and increased PP2A activity by activating ASMase, which may be an important mechanism in the inhibitory effect on AMPK phosphorylation and then contributed to the progression of steatosis. ASMase, a specific mechanism of ceramide generation, was proved to be a regulator of steatosis, fibrosis, lipotoxicity and endoplasmic reticulum stress.


Asunto(s)
Ceramidas/metabolismo , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/fisiopatología , Esfingomielina Fosfodiesterasa/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Hígado Graso/metabolismo , Humanos , Hepatopatías Alcohólicas/enzimología , Fosforilación , Proteína Fosfatasa 2/metabolismo
7.
J Biol Chem ; 288(46): 33263-71, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24100030

RESUMEN

TNF-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in transformed and tumor cells but not in normal cells, making it a promising agent for cancer therapy. However, many cancer cells are resistant to TRAIL, and the underlying mechanisms are not fully understood. Here, we show that the regulation of the PP2A and Src interaction plays a critical role in TRAIL resistance. Specifically, we show that TRAIL treatment activates the tyrosine kinase Src, which subsequently phosphorylates caspase-8 at tyrosine 380, leading to the inhibition of caspase-8 activation. We also show that upon TRAIL treatment, Src, caspase-8, and PP2A/C (a catalytic subunit of the PP2A phosphatase) are redistributed into lipid rafts, a microdomain of the plasma membrane enriched with cholesterol, where PP2A dephosphorylates Src at tyrosine 418 and in turn inhibits caspase-8 phosphorylation. Furthermore, we find that TRAIL treatment causes PP2A/C degradation. These data suggest that the balance between Src-mediated caspase-8 phosphorylation and the inactivation of Src-mediated caspase-8 phosphorylation by PP2A determines the outcome of TRAIL treatment in breast cancer cells. Therefore, this work identifies a novel mechanism by which the interaction between PP2A and Src in the context of caspase-8 activation modulates TRAIL sensitivity in cancer cells.


Asunto(s)
Apoptosis , Caspasa 8/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Proteína Fosfatasa 2/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Familia-src Quinasas/metabolismo , Caspasa 8/genética , Línea Celular Tumoral , Humanos , Microdominios de Membrana/genética , Microdominios de Membrana/metabolismo , Proteínas de Neoplasias/genética , Neoplasias/genética , Fosforilación/genética , Proteína Fosfatasa 2/genética , Proteolisis , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Familia-src Quinasas/genética
8.
Research (Wash D C) ; 7: 0355, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694202

RESUMEN

Proper timing of vigilance states serves fundamental brain functions. Although disturbance of sleep onset rapid eye movement (SOREM) sleep is frequently reported after orexin deficiency, their causal relationship still remains elusive. Here, we further study a specific subgroup of orexin neurons with convergent projection to the REM sleep promoting sublaterodorsal tegmental nucleus (OXSLD neurons). Intriguingly, although OXSLD and other projection-labeled orexin neurons exhibit similar activity dynamics during REM sleep, only the activation level of OXSLD neurons exhibits a significant positive correlation with the post-inter-REM sleep interval duration, revealing an essential role for the orexin-sublaterodorsal tegmental nucleus (SLD) neural pathway in relieving REM sleep pressure. Monosynaptic tracing reveals that multiple inputs may help shape this REM sleep-related dynamics of OXSLD neurons. Genetic ablation further shows that the homeostatic architecture of sleep/wakefulness cycles, especially avoidance of SOREM sleep-like transition, is dependent on this activity. A positive correlation between the SOREM sleep occurrence probability and depression states of narcoleptic patients further demonstrates the possible significance of the orexin-SLD pathway on REM sleep homeostasis.

9.
Alcohol Clin Exp Res ; 37(2): 213-22, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23009062

RESUMEN

BACKGROUND: To investigate whether "binge" and escalating alcohol exposure in the rat influences the development of pathological liver injury. METHODS: Time courses for the formation of eicosanoids by cyclooxygenase (COX), oxidative stress and nitrosative stress production, expression of hypoxia-inducible factor 1 (HIF-1), cytokines, hepatic tissue necroinflammation, and fibrosis were assessed in rats during 16 weeks of daily alcohol gavage. RESULTS: In this model of binge and escalating levels of alcohol, hepatic steatosis, necrosis, and inflammation as well as fibrosis were increased over the 16-week period. The levels of COX-2, oxidative stress, nitrosative stress, HIF-1, proinflammatory mediators (tumor necrosis factor-α, interleukin 1(ß) [IL-1(ß) ], IL-6), and procollagen-I were increased over the 16-week period. The content of IL-10 in rat serum increased at the end of 4 and 8 weeks but decreased thereafter and was significantly decreased at 12 and 16 weeks. CONCLUSIONS: A rat model of alcoholic liver disease (ALD) with long-term binge and escalating ethanol exposure was developed. Our data support the hypothesis that enhanced eicosanoid production by COX, oxidative stress and nitrosative stress, HIF-1, and the imbalance between pro- and anti-inflammatory cytokines plays an important role in the pathogenesis of ALD.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/patología , Etanol/efectos adversos , Inflamación/patología , Cirrosis Hepática/patología , Hígado/efectos de los fármacos , Hígado/patología , Animales , Consumo Excesivo de Bebidas Alcohólicas/sangre , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Factor 1 Inducible por Hipoxia/metabolismo , Inflamación/inducido químicamente , Mediadores de Inflamación/metabolismo , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Masculino , Necrosis/inducido químicamente , Necrosis/patología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Estrés Oxidativo/efectos de los fármacos , Procolágeno/metabolismo , Ratas , Ratas Wistar , Tirosina/análogos & derivados , Tirosina/metabolismo
10.
Hepatogastroenterology ; 60(122): 301-4, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23160168

RESUMEN

BACKGROUND/AIMS: Standard dose therapy with pegylated interferon α-2a (Peg-IFNα-2a) and ribavirin is not suitable for all patients because of the side effects. This study aims to evaluate the virological responses of low-dose but long-course Peg-IFNα-2a therapy compared with standard therapy. METHODOLOGY: Ninety patients with chronic hepatitis C were divided into three groups according to their tolerance to Peg-IFNα-2a. The courses of treatment were 96 or 48 weeks respectively in patients with HCV genotypes 1b or 2a in the 67.5 µg and 90 µg groups, and were 48 or 24 weeks in the 180 µg groups. Serum HCV RNA was quantified to determine RVR, EVR, SVR and ETR. RESULTS: There were no statistical differences in HCV RNA load, HCV genotype at the baseline of the three groups (p>0.05). The rates of RVR, EVR, SVR and ETR (no significant differences in each group), were 63.04%, 82.61%, 71.74% and 85.87% in all 92 patients. Genotype 1b (95% CI=11.97-82.89; p=0.0075) and RVR (95% CI=0.12-0.53; p<0.001) were important predictors of SVR. CONCLUSIONS: Patients with low-dose but long-course Peg-IFNα-2a therapy had similar virological responses compared to those with standard therapy. HCV genotype and RVR were independent predictors of SVR.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Adulto , Anciano , Genotipo , Hepatitis C/clasificación , Hepatitis C Crónica/virología , Humanos , Persona de Mediana Edad , ARN Viral/sangre , Proteínas Recombinantes/uso terapéutico
11.
Zhonghua Gan Zang Bing Za Zhi ; 21(1): 27-32, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23663759

RESUMEN

OBJECTIVE: To investigate the differential expression of programmed death-1 (PD-1) in the hepatitis B core antigen (HBcAg)17-28-specific CD8+ T cell subsets of adolescent patients with chronic hepatitis B virus (HBV) infection during the immune tolerant phase and the immune clearance phase. METHODS: A total of 105 patients between the ages of 12-28 years old (mean age 17.20+/-6.35) with chronic HBV infection and 15 healthy age-matched individuals were enrolled in the study. The patients were divided into two groups according to their current status in immune clearance phase (n = 55) or immune tolerant phase (n = 50), as determined by hepatic biopsy pathology. Flow cytometry was used to detect HLA-A2 type and PD-1 expression on peripheral blood mononuclear cells (PBMC) and HBcAg17-28-specific CD8+ T cells. PD-1 mRNA levels in PBMCs were measured by reverse transcription-polymerase chain reaction (RT-PCR). Independent samples t-test was used to compare means between the two groups, and one-way ANOVA was used to compare means among multiple groups. Pearson's correlation coefficient was used to assess the significance of correlation. RESULTS: The frequency of HBcAg18-27-specific CD8+ T cells was significantly higher in the immune clearance phase group than in the immune tolerant phase group (t = 18.08, P less than 0.01), but the expression of PD-1 on the HBcAg18-27 specific CD8+ T cells was significantly lower in the immune clearance phase group than in the immune tolerant phase group (t = 4.72, P less than 0.01). A negative correlation existed between the frequency of HBcAg18-27-specific CD8+ T cells and PD-1 expression (r = -0.463, P less than 0.01). A positive correlation existed between HBV viral load and PD-1 expression on the HBcAg18-27-specific CD8+ T cells in chronic HBV infection patients (r = 0.882, P less than 0.01), and there was a negative correlation between PD-1 expression levels on HBcAg18-27-specific CD8+ T cells and hepatic tissue inflammation score (r = -0.76, P less than 0.01). PD-1 mRNA in PBMCs was significantly higher in the immune tolerant phase group than in the immune clearance phase group (t = 30.89, P less than 0.01). CONCLUSION: Up-regulated expression of PD-1 is associated with HBV-specific CD8+ T cells and may play a crucial role in inhibiting their function during the immune tolerance phase of chronic HBV infection in adolescents.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B , Leucocitos Mononucleares , Adolescente , Linfocitos T CD8-positivos/metabolismo , Antígeno HLA-A2 , Virus de la Hepatitis B/genética , Hepatitis B Crónica/sangre , Humanos , Leucocitos Mononucleares/metabolismo , Subgrupos de Linfocitos T/metabolismo
12.
Zhonghua Gan Zang Bing Za Zhi ; 21(12): 899-902, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24636290

RESUMEN

OBJECTIVE: To investigate the dynamic changes that occur in T cell subsets, particularly involving the surface expression of programmed death 1 (PD-1), in response to pegylated (Peg)-interferon (IFN) a-2a therapy in patients with chronic hepatitis C virus (HCV) infection. METHODS: Twenty-five patients with HCV genotype 1b chronic infection and 10 healthy controls were enrolled in the study. All the HCV patients received combination antiviral therapy of Peg-IFNa-2a (180 mug/week) plus ribavirin. At treatment weeks 0 (baseline), 4, 12, 24 and 48, the level of PD-1 protein expression on the surface of total peripheral CD8+ and CD4+ T cells was determined by flow cytometry and the level of PD-1 mRNA expression in peripheral blood mononuclear cells (PBMCs) was determined by reverse transcription-polymerase chain reaction. Independent student's t-test were used to compare mean values between the two groups, repeat measure variance analysis was used to compare mean values among multiple groups, and Pearson's correlation coefficient was used to assess correlation significance. RESULTS: Over the course of antiviral therapy, the proportions of CD4+ T cells and CD8+ T cells, as well as the CD4+/CD8+ ratio, increased (F = 81.23, 39.28, and 7.01 respectively; all P less than 0.01). In contrast, the PD-1 protein expression frequency on CD4+ T cells and CD8+ T cells significantly declined (F = 100.11 and 158.40 respectively; all P less than 0.01). The PD-1-mRNA expression level in PBMCs was: 1.40+/-0.26 at baseline, 1.30+/-0.27 at week-4, 1.14+/-0.18 at week-12, 1.06+/-0.26 at week-24, and 0.83+/-0.25 at week-48 (F = 20.09; P less than 0.01). A positive correlation existed between the PD-1 protein expression frequencies on CD4+ T cells and CD8+ T cells and the HCV RNA load detected at baseline (r = 0.82 and 0.75 respectively; all P less than 0.01). CONCLUSION: The ability of Peg-IFN-a-2a-based antiviral therapy to suppress HCV replication may involve reduction of PD-1 protein expression on the surface of CD8+ T cells and CD4+ T cells.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Receptor de Muerte Celular Programada 1/metabolismo , Subgrupos de Linfocitos T/metabolismo , Adolescente , Adulto , Relación CD4-CD8 , Estudios de Casos y Controles , Femenino , Hepatitis C Crónica/inmunología , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Adulto Joven
13.
Cancers (Basel) ; 15(10)2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37345089

RESUMEN

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily that selectively induces apoptosis in tumor cells without harming normal cells, making it an attractive agent for cancer therapy. TRAIL induces apoptosis by binding to and activating its death receptors DR4 and DR5. Several TRAIL-based treatments have been developed, including recombinant forms of TRAIL and its death receptor agonist antibodies, but the efficacy of TRAIL-based therapies in clinical trials is modest. In addition to inducing cancer cell apoptosis, TRAIL is expressed in immune cells and plays a critical role in tumor surveillance. Emerging evidence indicates that the TRAIL pathway may interact with immune checkpoint proteins, including programmed death-ligand 1 (PD-L1), to modulate PD-L1-based tumor immunotherapies. Therefore, understanding the interaction between TRAIL and the immune checkpoint PD-L1 will lead to the development of new strategies to improve TRAIL- and PD-L1-based therapies. This review discusses recent findings on TRAIL-based therapy, resistance, and its involvement in tumor immunosurveillance.

14.
Am J Cancer Res ; 13(10): 4678-4692, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37970367

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer, and the majority of TNBC lacks targeted therapies. Previous studies have shown that TNBC cells are highly sensitive to TNF-related apoptosis-inducing ligand (TRAIL), making it a potentially viable treatment option for TNBC. However, the development of TRAIL resistance limits its potential for clinical use, and the underlying mechanisms are not fully understood. To better understand the mechanism of resistance to TRAIL, we performed RNA sequencing to identify the candidates that are responsible for resistance to TRAIL in two previously established TRAIL-resistant MDA231 and SUM159 cells. This approach led us to identify differentially expressed genes (DEGs) and pathways in TRAIL-resistant MDA231 and SUM159 cells compared to their TRAIL-sensitive counterparts. We showed that several DEGs and pathways were associated with inflammation in TRAIL-resistant cells, including IL-1α and IL6. By downregulating IL-1α and IL6 expression, we showed that TRAIL sensitivity can be significantly restored in TRAIL-resistant cells. Therefore, this study identifies a mechanism by which the inflammation pathway promotes TRAIL resistance, which could be targeted for enhancing TRAIL-based therapies in TNBC cells.

15.
Curr Med Sci ; 43(2): 417-420, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37037972

RESUMEN

Donor-derived infection (DDI) associated with Scedosporium spp is extremely rare, and results in a very poor prognosis. The present study reports a probable DDI due to Scedosporium boydii (S. boydii) from a donor with neuropsychiatric systemic lupus erythematosus. Two recipients developed Scedosporiosis after kidney transplantation from the same donor. Recipient 1 died of central nervous system infection due to S. boydii based on the clinical presentations, and the positive metagenomic next-generation sequencing (mNGS) and culture results for the cerebrospinal fluid. The other recipient with urinary tract obstruction due to S. boydii, which was identified through the positive culture and mNGS results of the removed stents, was successfully treated by stent replacement and voriconazole administration. Undiagnosed disseminated donor infection and the transmission of S. boydii should be given attention, particularly when the donor and recipients have primary immunodeficiency disease. The screening of donors and recipients for S. boydii using mNGS may be helpful in guiding antifungal prophylaxis and treatment recipients, due to its higher sensitivity and shorter diagnostic time relative to other traditional techniques.


Asunto(s)
Infecciones Fúngicas Invasoras , Trasplante de Riñón , Lupus Eritematoso Sistémico , Humanos , Trasplante de Riñón/efectos adversos , Voriconazol/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico
16.
J Biol Chem ; 286(25): 22384-92, 2011 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-21561860

RESUMEN

Cisplatin is the first-line chemotherapy for the treatment of several cancers. However, the development of cisplatin resistance represents a major clinical problem, and the mechanisms of acquired resistance are not fully understood. Here we show that degradation of the Bcl-2 homology 3-only proapoptotic protein Bim plays an important role in cisplatin resistance in ovarian cancer. Specifically, we show that treatment of ovarian cancer cells with cisplatin caused Bim phosphorylation and subsequent degradation and that its degradation is associated with cisplatin resistance. We also show that cisplatin treatment caused the activation of ERK, which correlated with Bim phosphorylation and degradation. By inhibiting ERK phosphorylation with the MEK inhibitor and knocking down ERK expression with siRNA, we show that Bim phosphorylation and degradation were blocked, which suggests that Bim is phosphorylated by ERK and that such phosphorylation is responsible for cisplatin-induced Bim degradation. We show that ERK was activated in cisplatin-resistant OV433 cells as compared with their counterpart parental OV433 cells. We also show that Bim was phosphorylated and degraded in cisplatin-resistant OV433 cells but not in the parental OV433 cells. Importantly, we show that inhibition of Bim degradation by the proteasome inhibitor MG132 sensitized resistant OV433 cells to cisplatin-induced death. Taken together, our data indicate that degradation of Bim via ERK-mediated phosphorylation can lead to cisplatin resistance. Therefore, these findings suggest that cisplatin resistance can be overcome by the combination of cisplatin and the proteasome inhibitors in ovarian cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo , Cisplatino/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteína 11 Similar a Bcl2 , Butadienos/farmacología , Muerte Celular/efectos de los fármacos , Muerte Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Resistencia a Antineoplásicos/genética , Activación Enzimática/efectos de los fármacos , Activación Enzimática/genética , Quinasas MAP Reguladas por Señal Extracelular/deficiencia , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Nitrilos/farmacología , Neoplasias Ováricas/patología , Fosforilación/efectos de los fármacos , Fosforilación/genética , Inhibidores de Proteasoma , Inhibidores de Proteínas Quinasas/farmacología , ARN Interferente Pequeño/genética
17.
Hepatogastroenterology ; 59(115): 680-6, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22441104

RESUMEN

BACKGROUND/AIMS: Monotherapy with pegylated interferon alpha (Peg-IFNa) or adefovir dipivoxil (ADV) to HBeAg-positive chronic hepatitis B (CHB) patients has limited effects. This study aims to evaluate therapeutic efficacy and safety of individualized combination therapy with Peg-IFNa and ADV. METHODOLOGY: HBeAg-positive CHB patients (n=160) were enrolled in this multi-center, prospective, randomized, 'real-life' cohort study, of which received Peg IFNa-2a monotherapy or combination therapy with ADV base on the baseline features and treatment response. RESULTS: At week 24, percentages of ALT normalization, HBV DNA undetectable were both higher in individualized treatment group (ITG, 57.50%, 43.75%) than that in standard treatment group (STG, 40.00%, 27.50%; p=0.027, 0.032). The superiority of HBeAg clearance and seroconversion rates in ITG maintained from treatment termination (63.75%, 56.25%) to 48 weeks follow-up (57.50%, 53.75%). At week 96 the combined response rates were 46.25% in ITG compared with 30.00% in STG (p=0.034). Furthermore, there was no statistically significant difference in relapse rates and adverse events between the two groups. CONCLUSIONS: Individualized combination therapy can achieve higher antiviral response rates. In particular, it can accelerate undetectable HBV DNA and elevate HBeAg clearance/seroconversion rates to a greater degree than Peg-IFNa-2a monotherapy.


Asunto(s)
Adenina/análogos & derivados , Antivirales/uso terapéutico , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Organofosfonatos/uso terapéutico , Polietilenglicoles/uso terapéutico , Adenina/efectos adversos , Adenina/uso terapéutico , Adulto , Alanina Transaminasa/sangre , Antivirales/efectos adversos , Biomarcadores/sangre , Distribución de Chi-Cuadrado , China , ADN Viral/sangre , Quimioterapia Combinada , Femenino , Virus de la Hepatitis B/genética , Hepatitis B Crónica/diagnóstico , Humanos , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Organofosfonatos/efectos adversos , Polietilenglicoles/efectos adversos , Medicina de Precisión , Estudios Prospectivos , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento
18.
Zhonghua Gan Zang Bing Za Zhi ; 20(1): 35-9, 2012 Jan.
Artículo en Zh | MEDLINE | ID: mdl-22464704

RESUMEN

OBJECTIVE: To investigate the role of endoplasmic reticulum stress (ERS) in alcoholic liver disease (ALD)-related hepatocyte apoptosis. METHODS: A rat model of ALD was established by continuous intragastric administration of ethanol. At 4, 8, 12, and 16 weeks later, randomly selected rats were sacrificed for serum and liver sample collection. Serum levels of total homocysteine (tHcy) were examined by chemiluminescence analysis. Cystathionine beta-synthase (CBS) activity in liver tissue was measured by chromatometry. The mRNA and protein expressions of ERS-related factors, glucose-regulated protein (GRP)-78, calpain 2 and caspase-12, were analyzed by reverse transcription-polymerase chain reaction and immunohistochemistry, respectively. Hepatocyte apoptosis was detected by the TdT-mediated dUTP nick end labeling assay. RESULTS: At 16 weeks, the ALD rats' livers exhibited diffuse microvesicular adipose degeneration and fibrosis in the liver sinus and portal septa. As the duration of ethanol administration extended, the tHcy levels gradually increased (P less than 0.01), CBS activity decreased (P less than 0.01), gene expression levels of GRP-78, calpain 2, and caspase-12 were up-regulated (P less than 0.01), and protein expression levels of GRP-78 and calpain 2 were gradually increased. However, the protein level of procaspase-12 was found to decrease with increased duration of ethanol administration. Finally, the hepatocyte apoptosis index showed an increasing trend over time (P less than 0.01). CONCLUSION: In our experimental ALD rat model, hepatic apoptosis was detected with increasing frequency over the duration of ALD. Increased apoptosis was likely due to decreased CBS activity causing hyperhomocysteinemia, which further induced ERS and activated the calpain 2 and caspase-12 signaling pathway. These ethanol-induced molecular changes may provoke hepatic apoptosis and subsequently promote the pathogenic processes of alcoholic liver disease.


Asunto(s)
Apoptosis , Estrés del Retículo Endoplásmico , Hepatocitos/patología , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/patología , Animales , Calpaína/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Hepatocitos/metabolismo , Hígado/patología , Masculino , Proteínas de la Membrana/metabolismo , Ratas , Ratas Wistar
19.
Front Oncol ; 12: 908603, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35847859

RESUMEN

Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis) are currently being used for treating breast cancer patients with deleterious or suspected deleterious germline BRCA-mutated, HER2-negative locally advanced or metastatic diseases. Despite durable responses, almost all patients receiving PARPis ultimately develop resistance and succumb to their illness, but the mechanism of PARPi resistance is not fully understood. To better understand the mechanism of PARPi resistance, we established two olaparib-resistant SUM159 and MDA468 cells by chronically exposing olaparib-sensitive SUM159 and MDA468 cells to olaparib. Olaparib-resistant SUM159 and MDA468 cells displayed 5-fold and 7-fold more resistance over their corresponding counterparts. Despite defects in PARPi-induced DNA damage, these olaparib-resistant cells are sensitive to cisplatin-induced cell death. Using an unbiased proteomic approach, we identified 6 447 proteins, of which 107 proteins were differentially expressed between olaparib-sensitive and -resistant cells. Ingenuity pathway analysis (IPA) revealed a number of pathways that are significantly altered, including mTOR and ubiquitin pathways. Among these differentially expressed proteins, p62/SQSTM1 (thereafter p62), a scaffold protein, plays a critical role in binding to and delivering the ubiquitinated proteins to the autophagosome membrane for autophagic degradation, was significantly downregulated in olaparib-resistant cells. We found that autophagy inducers rapamycin and everolimus synergistically sensitize olaparib-resistant cells to olaparib. Moreover, p62 protein expression was correlated with better overall survival in estrogen receptor-negative breast cancer. Thus, these findings suggest that PARPi-sensitive TNBC cells hyperactivate autophagy as they develop acquired resistance and that pharmacological stimulation of excessive autophagy could lead to cell death and thus overcome PARPi resistance.

20.
Zhonghua Yi Xue Za Zhi ; 91(1): 40-3, 2011 Jan 04.
Artículo en Zh | MEDLINE | ID: mdl-21418961

RESUMEN

OBJECTIVE: To investigate polysomnographic determinants of excessive daytime sleepiness (EDS) and potential relationship in Chinese patients with obstructive sleep apnea-hypopnea syndrome (OSAS). METHODS: A total of 410 patients with obstructive sleep apnea-hypopnea syndrome were analyzed retrospectively who were obtained in Sleep medicine center of West China hospital from January to April in 2010. All of the patients with an apnea-hypopnea index (AHI) greater than 5 h(-1) were evaluated using the Epworth Sleepiness Scale (ESS) and sleep disorders questionnaire. The patients who ESS score was more than 10 were defined as EDS; otherwise, the other was considered to without EDS. RESULTS: A total of 176 patients with EDS (ESS: 15 ± 3) and 234 without EDS (ESS: 6 ± 3) were studied. Patients with EDS were slightly higher BMI (28 ± 4 vs 26 ± 4) and shorter REM sleep latency (99 ± 65 vs 125 ± 81) than patients without EDS. Furthermore, there were significant difference in awake SaO2, AHI, minimum SaO2, oxygen desaturation index and arousal index between EDS group were No-EDS group (P < 0.001). There was a significant difference in waking SaO2 of severe OSAS between both groups. CONCLUSION: Long-term chronic hypoxia already exists in severe OSAS patients with prominent sleepiness. Waking SaO2 may play a role as a predictor in evaluation and diagnosis in patients with OSAS.


Asunto(s)
Trastornos de Somnolencia Excesiva/fisiopatología , Apnea Obstructiva del Sueño/fisiopatología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oximetría , Estudios Retrospectivos , Fases del Sueño , Encuestas y Cuestionarios , Vigilia
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