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1.
ESMO Open ; 9(9): 103699, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39255534

RESUMO

BACKGROUND: Trastuzumab deruxtecan (T-DXd) is approved for human epidermal growth factor receptor 2 (HER2)-positive and HER2-low advanced breast cancer (ABC). T-DXd has shown encouraging intracranial activity in HER2-positive ABC patients with stable or active brain metastases (BMs); however, its efficacy in patients with HER2-low ABC with BMs is not well established yet. METHODS: DEBBRAH is a single-arm, five-cohort, phase II study evaluating T-DXd in patients with central nervous system involvement from HER2-positive and HER2-low ABC. Here, we report results from patients with heavily pretreated HER2-low ABC and active BMs, enrolled in cohorts 2 (n = 6, asymptomatic untreated BMs) and 4 (n = 6, progressing BMs after local therapy). Patients received 5.4 mg/kg T-DXd intravenously once every 21 days. The primary endpoint was intracranial objective response rate per Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) for both cohorts. RESULTS: Intracranial objective response rate per RANO-BM was 50.0% [3/6 patients; 95% confidence interval (CI) 11.8% to 88.2%] and 33.3% [2/6 patients; 95% CI 4.3% to 77.7%; P = 0.033 (one-sided)] in cohorts 2 and 4, respectively. All responders had partial responses. Median time to intracranial response was 2.3 months (range, 1.5-4.0 months) and median duration of intracranial response was 7.2 months (range, 2.8-16.8 months). Median progression-free survival per RECIST v.1.1. was 5.4 months (95% CI 4.1-10.0 months). Treatment-emergent adverse events occurred in all patients included (16.7% grade 3). Three patients (25.0%) had grade 1 interstitial lung disease/pneumonitis. CONCLUSIONS: T-DXd demonstrated promising intracranial activity in pretreated HER2-low ABC patients with active BMs. Further studies are needed to validate these results in larger cohorts. This trial is registered with ClinicalTrials.gov, NCT04420598.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Camptotecina , Receptor ErbB-2 , Trastuzumab , Humanos , Feminino , Trastuzumab/uso terapêutico , Trastuzumab/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/tratamento farmacológico , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Idoso , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Camptotecina/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/farmacologia , Imunoconjugados/uso terapêutico , Imunoconjugados/farmacologia
2.
Biol Res ; 55(1): 8, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193678

RESUMO

BACKGROUND: Salmonella Typhimurium is a Gram-negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella-containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin-encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post-transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. RESULTS: In this work we sought to evaluate the transcriptional and post-transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S. Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild-type strain, suggesting that ompX mRNA is also regulated at a post-transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2-induced stress in Salmonella during the exponential growth phase in Lennox broth. CONCLUSIONS: Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium.


Assuntos
Proteínas da Membrana Bacteriana Externa/genética , Porinas , Salmonella typhimurium , Animais , Regulação Bacteriana da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Camundongos , Porinas/genética , Porinas/metabolismo , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
3.
Biol. Res ; 55: 8-8, 2022. ilus
Artigo em Inglês | LILACS | ID: biblio-1383912

RESUMO

BACKGROUND: Salmonella Typhimurium is a Gram negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. RESULTS: In this work we sought to evaluate the transcriptional and post transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S . Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild type strain, suggesting that ompX mRNA is also regulated at a post transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2 induced stress in Salmonella during the exponential growth phase in Lennox broth. CONCLUSIONS: Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium.


Assuntos
Animais , Camundongos , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Porinas/genética , Porinas/metabolismo , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Regulação Bacteriana da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia
4.
Sci Adv ; 7(17)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33893093

RESUMO

Existing three-dimensional (3D) culture techniques are limited by trade-offs between throughput, capacity for high-resolution imaging in living state, and geometric control. Here, we introduce a modular microscale hanging drop culture where simple design elements allow high replicates for drug screening, direct on-chip real-time or high-resolution confocal microscopy, and geometric control in 3D. Thousands of spheroids can be formed on our microchip in a single step and without any selective pressure from specific matrices. Microchip cultures from human LN229 glioblastoma and patient-derived mouse xenograft cells retained genomic alterations of originating tumors based on mate pair sequencing. We measured response to drugs over time with real-time microscopy on-chip. Last, by engineering droplets to form predetermined geometric shapes, we were able to manipulate the geometry of cultured cell masses. These outcomes can enable broad applications in advancing personalized medicine for cancer and drug discovery, tissue engineering, and stem cell research.


Assuntos
Ensaios de Triagem em Larga Escala , Esferoides Celulares , Animais , Técnicas de Cultura de Células/métodos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala/métodos , Humanos , Camundongos , Engenharia Tecidual/métodos
5.
Sci Rep ; 11(1): 2429, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510337

RESUMO

A correlated human red blood cell membrane fluctuation dependent on D-glucose concentration was found with dual time resolved membrane fluctuation spectroscopy (D-TRMFS). This new technique is a modified version of the dual optical tweezers method that has been adapted to measure the mechanical properties of red blood cells (RBCs) at distant membrane points simultaneously, enabling correlation analysis. Mechanical parameters under different D-glucose concentrations were obtained from direct membrane flickering measurements, complemented with membrane fluidity measurements using Laurdan Generalized Polarization (GP) Microscopy. Our results show an increase in the fluctuation amplitude of the lipid bilayer, and a decline in tension value, bending modulus and fluidity as D-glucose concentration increases. Metabolic mechanisms are proposed as explanations for the results.


Assuntos
Membrana Eritrocítica/fisiologia , Glucose/farmacologia , Análise Espectral , 2-Naftilamina/análogos & derivados , 2-Naftilamina/farmacologia , Adulto , Fenômenos Biomecânicos , Membrana Eritrocítica/efeitos dos fármacos , Humanos , Lauratos/farmacologia , Fluidez de Membrana/efeitos dos fármacos , Processamento de Sinais Assistido por Computador
6.
J Helminthol ; 94: e127, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32100663

RESUMO

Species of Anisakis typically infect the stomach of cetaceans worldwide, often causing ulcerative lesions that may compromise the host's health. These nematodes also cause anisakiasis or allergic reactions in humans. To assess the risks of this emerging zoonosis, data on long-term changes in Anisakis infections in cetaceans are necessary. Here, we compare the prevalence and severity of ulcerative lesions caused by Anisakis spp. in five cetacean species stranded along the north-west Spanish coast in 2017-2018 with published data from 1991-1996. Open ulcers were found in 32/43 short-beaked common dolphins, Delphinus delphis; 3/5 striped dolphins, Stenella coeruleoalba; 1/7 bottlenose dolphins, Tursiops truncatus; and 1/3 harbour porpoises, Phocoena phocoena meridionalis; a single individual of long-finned pilot whale, Globicephala melas, was found uninfected. In common dolphins, the mean abundance of open ulcers per host was 1.1 (95% confidence interval: 0.8-1.3), with a maximum diameter (mean ± standard deviation) of 25.4 ± 16.9 mm. Stomachs with scars or extensive fibrosis putatively associated with Anisakis were detected in 14 and five animals, respectively. A molecular analysis based on the mitochondrial cytochrome c oxidase II gene using 18 worms from three cetacean species revealed single or mixed infections of Anisakis simplex sensu stricto and Anisakis pegreffii. Compared with the period 1991-1996, we found a strong increase of prevalence, abundance and extension of ulcerative lesions in most cetacean species. Anisakis populations could have increased in the study area over the last decades, although we cannot rule out that a higher environmental stress has also boosted the pathological effects of these parasites.


Assuntos
Anisaquíase/veterinária , Anisakis/patogenicidade , Golfinhos/parasitologia , Estômago/patologia , Úlcera/parasitologia , Animais , Anisaquíase/epidemiologia , Anisaquíase/parasitologia , Oceano Atlântico/epidemiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Prevalência , Estômago/parasitologia , Úlcera/patologia
7.
Rev. chil. obstet. ginecol ; 81(5): 411-420, 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-830152

RESUMO

Se presenta el caso de paciente con ascitis, masa pelviana y CA 125 elevado, sugerentes de cáncer ovárico avanzado. Se realizó laparoscopía que demostró lesiones compatibles con tuberculosis peritoneal. La biopsia laparoscópica de las lesiones demostró granulomas, por lo que no se realizó más cirugía y se inició tratamiento antituberculoso específico con buena respuesta clínica. Se revisa en la literatura tuberculosis peritoneal y su dificultad con el diagnóstico diferencial con cáncer de ovario avanzado.


It is presented the case of a patient with ascites, pelvic mass and elevated CA 125, all suggested of advanced ovarian cancer. It was made a laparoscopy that evidenced lesions of peritoneal tuberculosis. The laparoscopic biopsy of the lesions demostrated granulomas, for that there was no more surgery made and antituberculosis specific treatment was started, with good clinical response. It is revisited in the literature peritoneal tuberculosis and its difficult differential diagnoses with advanced ovarian cancer.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Peritonite Tuberculosa/diagnóstico , Peritonite Tuberculosa/terapia , Antibacterianos/uso terapêutico , Ascite/etiologia , Diagnóstico Diferencial , Laparoscopia , Neoplasias Ovarianas/diagnóstico , Peritonite Tuberculosa/complicações
8.
Rev. chil. obstet. ginecol ; 80(5): 414-420, ago. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-764074

RESUMO

Cáncer epitelial de ovario es una enfermedad altamente letal. Constituye la quinta causa de muerte por cáncer en mujeres a nivel mundial. El subtipo histológico más frecuente es el carcinoma seroso de alto grado. Este es el responsable de la alta letalidad de la enfermedad. Se presenta evidencia que respalda el origen tubario de este tipo histológico desde lesiones precursoras. A partir de estos datos se ha establecido que el cáncer tradicionalmente conocido como cáncer ovárico seroso de alto grado, el cáncer de trompa de Falopio y el carcinoma peritoneal primario, corresponden a una misma entidad nosológica: cáncer seroso pélvico de alto grado. Se revisa además la evidencia disponible para establecer que la salpingectomía podría constituir una medida de prevención para este tipo de cáncer.


Epithelial ovarian cancer is a highly lethal disease. It is the 5th cause of cancer death in women worldwide. The most common histologic subtype is the high-grade serous carcinoma. This is the responsible for the high lethality of the disease. Evidence supporting the tubal origin of this histological type from precursor lesions is presented. From these data it has been established that cancer traditionally known as serous high-grade ovarian cancer, cancer of the fallopian tube and primary peritoneal carcinoma, correspond to a single disease entity: pelvic serous high-grade cancer. We also check the available evidence to establish that the salpingectomy could be a preventive measure for this type of cancer.


Assuntos
Humanos , Feminino , Neoplasias Ovarianas/etiologia , Neoplasias Ovarianas/patologia , Tubas Uterinas/patologia , Carcinoma Epitelial do Ovário/etiologia , Carcinoma Epitelial do Ovário/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/prevenção & controle , Proteína Supressora de Tumor p53 , Tubas Uterinas/cirurgia , Salpingectomia , Gradação de Tumores , Carcinogênese , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/prevenção & controle
9.
Clin Exp Immunol ; 182(2): 173-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26174440

RESUMO

Epstein-Barr virus (EBV) is a persistent virus with oncogenic capacity that has been implicated in the development of aggressive B cell lymphomas, primarily in immunosuppressed individuals, although it can be present in immunocompetent individuals. Changes in the function and clonal diversity of T lymphocytes might be implied by viral persistence and lymphoma development. The aim of the present study was to evaluate the frequency, phenotype, function and clonotypical distribution of EBV-specific T cells after peripheral blood stimulation with a virus lysate in newly diagnosed patients with diffuse large B cell lymphoma (DLBCL) aged more than 50 years without prior histories of clinical immunosuppression compared with healthy controls. Our results showed impaired EBV-specific immune responses among DLBCL patients that were associated primarily with decreased numbers of central and effector memory CD8(+) T lymphocytes. In contrast to healthy controls, only a minority of the patients showed CD4(+)/tumour necrosis factor (TNF)-α(+) T cells expressing T cell receptor (TCR)-Vß17 and CD8(+)/TNF-α(+) T cells with TCR-Vß5·2, Vß9 and Vß18 in response to EBV. Notably, the production of TNF-α was undetectable among TCR-Vß5·3(+), Vß11(+), Vß12(+), Vß16(+) and Vß23(+) CD8(+) T cells. In addition, we observed decreased numbers of CD4(+)/TNF-α(+) and CD8(+)/TNF-α(+), CD8(+)/interleukin (IL)-2(+) and CD8(+)/TNF-α(+)/IL-2(+) T lymphocytes in the absence of T cells capable of producing TNF-α, IL-2 and IFN-γ after EBV stimulation simultaneously. Moreover, DLBCL patients displayed higher IL-10 levels both under baseline conditions and after EBV stimulation. These findings were also observed in patients with positive EBV viral loads. Prospective studies including a large number of patients are needed to confirm these findings.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Linfoma Difuso de Grandes Células B/imunologia , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/virologia , Feminino , Citometria de Fluxo , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Interleucina-2/imunologia , Interleucina-2/metabolismo , Contagem de Linfócitos , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/virologia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Carga Viral/imunologia
10.
Infect Genet Evol ; 33: 131-42, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25913156

RESUMO

The difference in host range between Salmonella enterica serovar Typhimurium (S. Typhimurium) and S. enterica serovar Typhi (S. Typhi) can be partially attributed to pseudogenes. Pseudogenes are genomic segments homologous to functional genes that do not encode functional products due to the presence of genetic defects. S. Typhi lacks several protein effectors implicated in invasion or other important processes necessary for full virulence of S. Typhimurium. SopA and SopE2, effectors that have been lost by pseudogenization in S. Typhi, correspond to an ubiquitin ligase involved in cytokine production by infected cells, and to a guanine exchange factor necessary for invasion of epithelial cells, respectively. We hypothesized that sopA and/or sopE pseudogenization contributed to the virulence of S. Typhi. In this work, we found that S. Typhi expressing S. Typhimurium sopE2 exhibited a decreased invasion in different epithelial cell lines compared with S. Typhi WT. S. Typhimurium sopA completely abolished the hypo-invasive phenotype observed in S. Typhi expressing S. Typhimurium sopE2, suggesting that functional SopA and SopE2 participate concertedly in the invasion process. Finally, the expression of S. Typhimurium sopA and/or sopE2 in S. Typhi, determined changes in the secretion of IL-8 and IL-18 in infected epithelial cells.


Assuntos
Proteínas de Bactérias/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Salmonella typhi/genética , Salmonella typhi/patogenicidade , Febre Tifoide/microbiologia , Virulência/genética , Proteínas de Bactérias/metabolismo , Citocinas/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Expressão Gênica , Genótipo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Mutação , Pseudogenes
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