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1.
Nature ; 555(7696): 334-337, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29482193

RESUMEN

Our Galaxy is thought to have an active evolutionary history, dominated over the past ten billion years or so by star formation, the accretion of cold gas and, in particular, the merging of clumps of baryonic and dark matter. The stellar halo-the faint, roughly spherical component of the Galaxy-reveals rich 'fossil' evidence of these interactions, in the form of stellar streams, substructures and chemically distinct stellar components. The effects of interactions with dwarf galaxies on the content and morphology of the Galactic disk are still being explored. Recent studies have identified kinematically distinct stellar substructures and moving groups of stars in our Galaxy, which may have extragalactic origins. There is also mounting evidence that stellar overdensities (regions with greater-than-average stellar density) at the interface between the outer disk and the halo could have been caused by the interaction of a dwarf galaxy with the disk. Here we report a spectroscopic analysis of 14 stars from two stellar overdensities, each lying about five kiloparsecs above or below the Galactic plane-locations suggestive of an association with the stellar halo. We find that the chemical compositions of these two groups of stars are almost identical, both within and between these overdensities, and closely match the abundance patterns of stars in the Galactic disk. We conclude that these stars came from the disk, and that the overdensities that they are part of were created by tidal interactions of the disk with passing or merging dwarf galaxies.

2.
Lancet Oncol ; 24(5): 509-522, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37142373

RESUMEN

BACKGROUND: Low-intensity pulsed ultrasound with concomitant administration of intravenous microbubbles (LIPU-MB) can be used to open the blood-brain barrier. We aimed to assess the safety and pharmacokinetics of LIPU-MB to enhance the delivery of albumin-bound paclitaxel to the peritumoural brain of patients with recurrent glioblastoma. METHODS: We conducted a dose-escalation phase 1 clinical trial in adults (aged ≥18 years) with recurrent glioblastoma, a tumour diameter of 70 mm or smaller, and a Karnofsky performance status of at least 70. A nine-emitter ultrasound device was implanted into a skull window after tumour resection. LIPU-MB with intravenous albumin-bound paclitaxel infusion was done every 3 weeks for up to six cycles. Six dose levels of albumin-bound paclitaxel (40 mg/m2, 80 mg/m2, 135 mg/m2, 175 mg/m2, 215 mg/m2, and 260 mg/m2) were evaluated. The primary endpoint was dose-limiting toxicity occurring during the first cycle of sonication and albumin-bound paclitaxel chemotherapy. Safety was assessed in all treated patients. Analyses were done in the per-protocol population. Blood-brain barrier opening was investigated by MRI before and after sonication. We also did pharmacokinetic analyses of LIPU-MB in a subgroup of patients from the current study and a subgroup of patients who received carboplatin as part of a similar trial (NCT03744026). This study is registered with ClinicalTrials.gov, NCT04528680, and a phase 2 trial is currently open for accrual. FINDINGS: 17 patients (nine men and eight women) were enrolled between Oct 29, 2020, and Feb 21, 2022. As of data cutoff on Sept 6, 2022, median follow-up was 11·89 months (IQR 11·12-12·78). One patient was treated per dose level of albumin-bound paclitaxel for levels 1 to 5 (40-215 mg/m2), and 12 patients were treated at dose level 6 (260 mg/m2). A total of 68 cycles of LIPU-MB-based blood-brain barrier opening were done (median 3 cycles per patient [range 2-6]). At a dose of 260 mg/m2, encephalopathy (grade 3) occurred in one (8%) of 12 patients during the first cycle (considered a dose-limiting toxicity), and in one other patient during the second cycle (grade 2). In both cases, the toxicity resolved and treatment continued at a lower dose of albumin-bound paclitaxel, with a dose of 175 mg/m2 in the case of the grade 3 encephalopathy, and to 215 mg/m2 in the case of the grade 2 encephalopathy. Grade 2 peripheral neuropathy was observed in one patient during the third cycle of 260 mg/m2 albumin-bound paclitaxel. No progressive neurological deficits attributed to LIPU-MB were observed. LIPU-MB-based blood-brain barrier opening was most commonly associated with immediate yet transient grade 1-2 headache (12 [71%] of 17 patients). The most common grade 3-4 treatment-emergent adverse events were neutropenia (eight [47%]), leukopenia (five [29%]), and hypertension (five [29%]). No treatment-related deaths occurred during the study. Imaging analysis showed blood-brain barrier opening in the brain regions targeted by LIPU-MB, which diminished over the first 1 h after sonication. Pharmacokinetic analyses showed that LIPU-MB led to increases in the mean brain parenchymal concentrations of albumin-bound paclitaxel (from 0·037 µM [95% CI 0·022-0·063] in non-sonicated brain to 0·139 µM [0·083-0·232] in sonicated brain [3·7-times increase], p<0·0001) and carboplatin (from 0·991 µM [0·562-1·747] in non-sonicated brain to 5·878 µM [3·462-9·980] µM in sonicated brain [5·9-times increase], p=0·0001). INTERPRETATION: LIPU-MB using a skull-implantable ultrasound device transiently opens the blood-brain barrier allowing for safe, repeated penetration of cytotoxic drugs into the brain. This study has prompted a subsequent phase 2 study combining LIPU-MB with albumin-bound paclitaxel plus carboplatin (NCT04528680), which is ongoing. FUNDING: National Institutes of Health and National Cancer Institute, Moceri Family Foundation, and the Panattoni family.


Asunto(s)
Encefalopatías , Glioblastoma , Adulto , Masculino , Humanos , Femenino , Adolescente , Paclitaxel Unido a Albúmina/efectos adversos , Carboplatino , Glioblastoma/diagnóstico por imagen , Glioblastoma/tratamiento farmacológico , Barrera Hematoencefálica , Paclitaxel , Encefalopatías/inducido químicamente , Encefalopatías/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
3.
Nature ; 546(7659): 514-518, 2017 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-28582774

RESUMEN

The amount of ultraviolet irradiation and ablation experienced by a planet depends strongly on the temperature of its host star. Of the thousands of extrasolar planets now known, only six have been found that transit hot, A-type stars (with temperatures of 7,300-10,000 kelvin), and no planets are known to transit the even hotter B-type stars. For example, WASP-33 is an A-type star with a temperature of about 7,430 kelvin, which hosts the hottest known transiting planet, WASP-33b (ref. 1); the planet is itself as hot as a red dwarf star of type M (ref. 2). WASP-33b displays a large heat differential between its dayside and nightside, and is highly inflated-traits that have been linked to high insolation. However, even at the temperature of its dayside, its atmosphere probably resembles the molecule-dominated atmospheres of other planets and, given the level of ultraviolet irradiation it experiences, its atmosphere is unlikely to be substantially ablated over the lifetime of its star. Here we report observations of the bright star HD 195689 (also known as KELT-9), which reveal a close-in (orbital period of about 1.48 days) transiting giant planet, KELT-9b. At approximately 10,170 kelvin, the host star is at the dividing line between stars of type A and B, and we measure the dayside temperature of KELT-9b to be about 4,600 kelvin. This is as hot as stars of stellar type K4 (ref. 5). The molecules in K stars are entirely dissociated, and so the primary sources of opacity in the dayside atmosphere of KELT-9b are probably atomic metals. Furthermore, KELT-9b receives 700 times more extreme-ultraviolet radiation (that is, with wavelengths shorter than 91.2 nanometres) than WASP-33b, leading to a predicted range of mass-loss rates that could leave the planet largely stripped of its envelope during the main-sequence lifetime of the host star.

4.
Neurosurg Focus ; 55(4): E3, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37778050

RESUMEN

OBJECTIVE: The use of anticoagulation to prevent venous thromboembolism (VTE) is controversial in the setting of neurosurgical decompression for traumatic subdural hematoma (SDH). In these patients, there is concern that anticoagulation may cause secondary hemorrhage, increasing the risk of death and other complications. Patients with a history of anticoagulant use are at further risk of VTE, but the effect of VTE prophylaxis (VTEP) following neurosurgery for SDH has not been thoroughly investigated in this population. This study aims to investigate the differences in in-hospital outcomes in patients with SDH and preexisting anticoagulant use who received VTEP following neurosurgical intervention compared with those who did not. METHODS: The National Trauma Data Bank was queried from 2017 to 2019 for all patients with preexisting anticoagulant use presenting with an SDH who subsequently underwent neurosurgical intervention. Patients who received VTEP were propensity score matched with patients who did not based on demographics, insurance type, injury severity, and comorbidities. Paired Student t-tests, Pearson's chi-square tests, and Benjamini-Hochberg multiple comparisons correction were used to compare differences in in-hospital complications, length of stay (LOS), and mortality rate between the two groups. A logistic regression model was developed to identify risk factors for in-hospital mortality. RESULTS: Two thousand seven hundred ninety-four patients matching the inclusion criteria were identified, of whom 950 received VTEP. Following one-to-one matching and multiple comparisons correction, the VTEP group had a lower mortality rate (18.53% vs 34.53%, p < 0.001) but longer LOS (14.09 vs 8.57 days, p < 0.001) and higher rates of pressure ulcers (2.11% vs 0.53%, p = 0.01), unplanned intensive care unit admission (9.05% vs 3.47%, p < 0.001), and unplanned intubation (9.47% vs 6.11%, p = 0.021). The multivariable logistic regression showed that use of unfractionated heparin (UH; OR 0.36, p < 0.001) and low-molecular-weight heparin (LMWH; OR 0.3, p < 0.001) were associated with lower odds of in-hospital mortality. CONCLUSIONS: In patients with traumatic SDH and a history of anticoagulant use, perioperative VTEP was associated with increased LOS but provided a mortality benefit. LMWH and UH use were the strongest predictors of survival.


Asunto(s)
Heparina , Tromboembolia Venosa , Humanos , Heparina/uso terapéutico , Heparina de Bajo-Peso-Molecular/efectos adversos , Tromboembolia Venosa/prevención & control , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Anticoagulantes/efectos adversos , Hematoma Subdural/cirugía , Factores de Riesgo , Estudios Retrospectivos
5.
Am J Physiol Renal Physiol ; 317(6): F1503-F1512, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31532245

RESUMEN

We have defined a population of stem cell antigen (Sca)-1+/CD34+/lin- mesenchymal stem cells in the mouse urinary bladder. These cells are reduced after partial bladder outlet obstruction (PO). To test the role of Sca-1 expressed by these cells, we analyzed bladders from Sca-1 knockout (KO) mice in both uninjured male mice and male mice subjected to PO. We found that loss of Sca-1 alone had little effect on bladder development or function but reduced the total number of mesenchymal stem cells by 30%. After PO, bladders from Sca-1-null KO male mice were larger, with more collagen and less muscle, than obstructed wild-type mice. Steady-state levels of caldesmon were significantly reduced and levels of fibroblast-specific protein 1 were significantly increased in Sca-1 KO mice compared with wild-type mice after PO. In investigating the effects of PO on cell proliferation, we found that loss of Sca-1 changed the timing of cell division in CD34+/lin-, collagen-producing, and smooth muscle cells. PO in combination with loss of Sca-1 drastically reduced the ability of CD34+/lin- cells to form colonies in vitro. Our findings therefore support the hypothesis that Sca-1 protects the bladder from fibrotic remodeling after obstruction, in part by influencing the proliferation of cells responding to the injury.


Asunto(s)
Antígenos Ly/uso terapéutico , Proteínas de la Membrana/uso terapéutico , Vejiga Urinaria/patología , Animales , Antígenos/inmunología , Antígenos/uso terapéutico , Antígenos CD34/metabolismo , Antígenos Ly/genética , Antígenos Ly/inmunología , Proteínas de Unión a Calmodulina/metabolismo , Proliferación Celular , Fibrosis , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Células Madre Mesenquimatosas/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Miocitos del Músculo Liso/metabolismo , Sustancias Protectoras , Células Madre , Obstrucción del Cuello de la Vejiga Urinaria/patología
6.
Chembiochem ; 18(14): 1350-1363, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28544675

RESUMEN

Cyclotides are globular microproteins with a unique head-to-tail cyclized backbone, stabilized by three disulfide bonds forming a cystine knot. This unique circular backbone topology and knotted arrangement of three disulfide bonds makes them exceptionally stable to chemical, thermal, and biological degradation compared to other peptides of similar size. In addition, cyclotides have been shown to be highly tolerant to sequence variability, aside from the conserved residues forming the cystine knot. Cyclotides can also cross cellular membranes and are able to modulate intracellular protein-protein interactions, both in vitro and in vivo. All of these features make cyclotides highly promising as leads or frameworks for the design of peptide-based diagnostic and therapeutic tools. This article provides an overview on cyclotides and their applications as molecular imaging agents and peptide-based therapeutics.


Asunto(s)
Biotecnología/métodos , Ciclotidas/química , Ciclotidas/uso terapéutico , Imagen Molecular/métodos , Animales , Ciclotidas/farmacología , Humanos , Modelos Moleculares , Sondas Moleculares/química , Sondas Moleculares/farmacología , Sondas Moleculares/uso terapéutico , Plantas/química , Proteínas/antagonistas & inhibidores , Proteínas/metabolismo
7.
Angew Chem Int Ed Engl ; 54(29): 8390-4, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26096948

RESUMEN

We report for the first time the recombinant expression of fully folded bioactive cyclotides inside live yeast cells by using intracellular protein trans-splicing in combination with a highly efficient split-intein. This approach was successfully used to produce the naturally occurring cyclotide MCoTI-I and the engineered bioactive cyclotide MCoCP4. Cyclotide MCoCP4 was shown to reduce the toxicity of human α-synuclein in live yeast cells. Cyclotide MCoCP4 was selected by phenotypic screening from cells transformed with a mixture of plasmids encoding MCoCP4 and inactive cyclotide MCoTI-I in a ratio of 1:5×10(4). This demonstrates the potential for using yeast to perform phenotypic screening of genetically encoded cyclotide-based libraries in eukaryotic cells.


Asunto(s)
Ciclotidas/genética , Ciclotidas/farmacología , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/genética , alfa-Sinucleína/metabolismo , Secuencia de Aminoácidos , Ciclotidas/química , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Ingeniería de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Saccharomyces cerevisiae/metabolismo , Trans-Empalme , Transformación Genética
8.
Clin Cancer Res ; 30(8): 1619-1629, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38295144

RESUMEN

PURPOSE: We recently reported on clinical trials for patients with recurrent glioblastoma where low-intensity pulsed ultrasound and microbubbles (LIPU/MB) improved paclitaxel or carboplatin delivery into the brain. Here, we report variable local tumor control with paclitaxel at the maximal/target dose in our phase I trial (NCT04528680). To address this, we investigated the combination of paclitaxel with carboplatin in preclinical glioma models. EXPERIMENTAL DESIGN: We performed MRI-based analysis to evaluate disease control in patients from our trial. We studied the cytotoxicity of paclitaxel and carboplatin against 11 human glioma lines as monotherapy and in combination at concentrations derived from human intraoperative studies. Synergy was assessed with the Loewe model and the survival benefit evaluated in two xenografts. We examined the effects on cell cycle progression, DNA damage, and apoptosis. RESULTS: Patients treated with paclitaxel and LIPU/MB exhibited variable local tumor control, which correlated with overall survival. We observed limited cross-resistance to paclitaxel and carboplatin in glioma lines, with almost a third of them being exclusively susceptible to one drug. This combination led to susceptibility of 81% of lines and synergy in 55% of them. The combination proved more efficacious in two intracranial xenografts when administered with LIPU/MB, leading to complementary effects on cell cycle arrest. CONCLUSIONS: Combining paclitaxel and carboplatin in gliomas may be more efficacious than monotherapy, as in other cancers, due to synergy and independent susceptibility to each drug. These results form the basis for an ongoing phase II trial (NCT04528680) where we investigate this combination with LIPU/MB.


Asunto(s)
Glioblastoma , Glioma , Humanos , Carboplatino , Paclitaxel , Glioblastoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Glioma/tratamiento farmacológico
9.
Clin Cancer Res ; 30(2): 379-388, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-37939133

RESUMEN

PURPOSE: Evidence suggests that MAPK pathway activation, as measured by ERK1/2 phosphorylation (p-ERK), predicts overall survival (OS) in patients with recurrent glioblastoma receiving anti-PD-1 therapy. We aimed to validate these findings in independent cohorts. EXPERIMENTAL DESIGN: In a 24-patient clinical trial on recurrent glioblastoma and high-grade gliomas, we examined the link between p-ERK levels and OS. Patients received intravenous nivolumab, followed by maximal safe resection and an intracerebral injection of either ipilimumab alone or combined with nivolumab. Biweekly adjuvant nivolumab was then administered up to five times (NCT03233152). Using REporting recommendations for tumor MARKER prognostic studies (REMARK) criteria, we conducted independent analyses for p-ERK quantification and statistical evaluations. Additional comparative analysis included prior cohorts, totaling 65 patients. Cox proportional hazards models and meta-analysis were employed to assess p-ERK as a predictive biomarker after immunotherapy. RESULTS: Lower median p-ERK+ cell density was observed compared with prior studies, likely due to variable tissue processing across cohorts. Nonetheless, high p-ERK was associated with prolonged OS, particularly in isocitrate dehydrogenase wild-type glioblastomas (P = 0.036). Median OS for high and low p-ERK patients were 55.6 and 30 weeks, respectively. Multivariable analysis reinforced p-ERK's significance in survival prediction (P = 0.011). Upon p-ERK normalization across cohorts (n = 65), meta-analysis supported the survival benefit of elevated tumor p-ERK levels (P = 0.0424). CONCLUSIONS: This study strengthens the role of p-ERK as a predictive biomarker for OS in patients with glioblastoma on immune checkpoint blockade. Future research should focus on further validation in prospective trials and the standardization of preanalytical variables influencing p-ERK quantification.


Asunto(s)
Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Antígeno CTLA-4 , Nivolumab/uso terapéutico , Receptor de Muerte Celular Programada 1 , Fosforilación , Sistema de Señalización de MAP Quinasas , Estudios Prospectivos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Ipilimumab/uso terapéutico , Adyuvantes Inmunológicos/uso terapéutico , Inmunoterapia
10.
Neuro Oncol ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028616

RESUMEN

BACKGROUND: Glioblastoma is a highly aggressive brain cancer that is resistant to conventional immunotherapy strategies. Botensilimab, an Fc-enhanced anti-CTLA-4 antibody (FcE-aCTLA-4), has shown durable activity in "cold" and immunotherapy-refractory cancers. METHOD: We evaluated the efficacy and immune microenvironment phenotype of a mouse analogue of FcE-aCTLA-4 in treatment-refractory preclinical models of glioblastoma, both as a monotherapy and in combination with doxorubicin delivered via low-intensity pulsed ultrasound and microbubbles (LIPU/MB). Additionally, we studied 4 glioblastoma patients treated with doxorubicin, anti-PD-1 with concomitant LIPU/MB to investigate the novel effect of doxorubicin modulating FcγR expressions in tumor associated macrophages/microglia (TAMs). RESULTS: FcE-aCTLA-4 demonstrated high-affinity binding to FcγRIV, the mouse ortholog of human FcγRIIIA, which was highly expressed in TAMs in human glioblastoma, most robustly at diagnosis. Notably, FcE-aCTLA-4 mediated selective depletion of intra-tumoral regulatory T cells (Tregs) via TAM-mediated phagocytosis, while sparing peripheral Tregs. Doxorubicin, a chemotherapeutic drug with immunomodulatory functions, was found to upregulate FcγRIIIA on TAMs in glioblastoma patients who received doxorubicin and anti-PD-1 with concomitant LIPU/MB. In murine models of immunotherapy-resistant gliomas, a combinatorial regimen of FcE-aCTLA-4, anti-PD-1, and doxorubicin with LIPU/MB, achieved a 90% cure rate, that was associated robust infiltration of activated CD8+ T cells and establishment of immunological memory as evidenced by rejection upon tumor rechallenge. CONCLUSION: Our findings demonstrate that FcE-aCTLA-4 promotes robust immunomodulatory and anti-tumor effects in murine gliomas and is significantly enhanced when combined with anti-PD-1, doxorubicin, and LIPU/MB. We are currently investigating this combinatory strategy in a clinical trial (clinicaltrials.gov NCT05864534).

11.
Nat Commun ; 15(1): 4698, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844770

RESUMEN

Given the marginal penetration of most drugs across the blood-brain barrier, the efficacy of various agents remains limited for glioblastoma (GBM). Here we employ low-intensity pulsed ultrasound (LIPU) and intravenously administered microbubbles (MB) to open the blood-brain barrier and increase the concentration of liposomal doxorubicin and PD-1 blocking antibodies (aPD-1). We report results on a cohort of 4 GBM patients and preclinical models treated with this approach. LIPU/MB increases the concentration of doxorubicin by 2-fold and 3.9-fold in the human and murine brains two days after sonication, respectively. Similarly, LIPU/MB-mediated blood-brain barrier disruption leads to a 6-fold and a 2-fold increase in aPD-1 concentrations in murine brains and peritumoral brain regions from GBM patients treated with pembrolizumab, respectively. Doxorubicin and aPD-1 delivered with LIPU/MB upregulate major histocompatibility complex (MHC) class I and II in tumor cells. Increased brain concentrations of doxorubicin achieved by LIPU/MB elicit IFN-γ and MHC class I expression in microglia and macrophages. Doxorubicin and aPD-1 delivered with LIPU/MB results in the long-term survival of most glioma-bearing mice, which rely on myeloid cells and lymphocytes for their efficacy. Overall, this translational study supports the utility of LIPU/MB to potentiate the antitumoral activities of doxorubicin and aPD-1 for GBM.


Asunto(s)
Barrera Hematoencefálica , Neoplasias Encefálicas , Doxorrubicina , Microburbujas , Receptor de Muerte Celular Programada 1 , Doxorrubicina/farmacología , Doxorrubicina/administración & dosificación , Doxorrubicina/uso terapéutico , Doxorrubicina/análogos & derivados , Animales , Humanos , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Ratones , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Glioma/inmunología , Glioma/patología , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Femenino , Sistemas de Liberación de Medicamentos , Ondas Ultrasónicas , Glioblastoma/tratamiento farmacológico , Glioblastoma/inmunología , Glioblastoma/patología , Masculino , Microglía/efectos de los fármacos , Microglía/metabolismo , Ratones Endogámicos C57BL , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/farmacología , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Polietilenglicoles
12.
Nat Commun ; 14(1): 1566, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949040

RESUMEN

Whereas the contribution of tumor microenvironment to the profound immune suppression of glioblastoma (GBM) is clear, tumor-cell intrinsic mechanisms that regulate resistance to CD8 T cell mediated killing are less understood. Kinases are potentially druggable targets that drive tumor progression and might influence immune response. Here, we perform an in vivo CRISPR screen to identify glioma intrinsic kinases that contribute to evasion of tumor cells from CD8 T cell recognition. The screen reveals checkpoint kinase 2 (Chek2) to be the most important kinase contributing to escape from CD8 T-cell recognition. Genetic depletion or pharmacological inhibition of Chek2 with blood-brain-barrier permeable drugs that are currently being evaluated in clinical trials, in combination with PD-1 or PD-L1 blockade, lead to survival benefit in multiple preclinical glioma models. Mechanistically, loss of Chek2 enhances antigen presentation, STING pathway activation and PD-L1 expression in mouse gliomas. Analysis of human GBMs demonstrates that Chek2 expression is inversely associated with antigen presentation and T-cell activation. Collectively, these results support Chek2 as a promising target for enhancement of response to immune checkpoint blockade therapy in GBM.


Asunto(s)
Glioblastoma , Glioma , Humanos , Animales , Ratones , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Antígeno B7-H1 , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Linfocitos T CD8-positivos , Inmunidad , Microambiente Tumoral
13.
Otolaryngol Head Neck Surg ; 169(3): 701-709, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37003297

RESUMEN

OBJECTIVE: Evaluate 2-year outcomes after lidocaine/epinephrine iontophoresis and tympanostomy using an automated tube delivery system for pediatric tube placement in-office. STUDY DESIGN: Prospective, single-arm. SETTING: Eighteen otolaryngology practices. METHODS: Children age 6 months to 12 years indicated for tympanostomy were enrolled between October 2017 and February 2019. Local anesthesia of the tympanic membrane was achieved via lidocaine/epinephrine iontophoresis and tympanostomy was completed using an automated tube delivery system (the Tula® System). An additional Lead-In cohort of patients underwent tube placement in the operating room (OR) under general anesthesia using only the tube delivery system. Patients were followed for 2 years or until tube extrusion, whichever occurred first. Otoscopy and tympanometry were performed at 3 weeks, and 6, 12, 18, and 24 months. Tube retention, patency, and safety were evaluated. RESULTS: Tubes were placed in-office for 269 patients (449 ears) and in the OR for 68 patients (131 ears) (mean age, 4.5 years). The median and mean times to tube extrusion for the combined OR and In-Office cohorts were 15.82 (95% confidence interval [CI]: 15.41-19.05) and 16.79 (95% CI: 16.16-17.42) months, respectively. Sequelae included ongoing perforation for 1.9% of ears (11/580) and medial tube displacement for 0.2% (1/580) observed at 18 months. Over a mean follow-up of 14.3 months, 30.3% (176/580) of ears had otorrhea and 14.3% (83/580) had occluded tubes. CONCLUSION: In-office pediatric tympanostomy using lidocaine/epinephrine iontophoresis and automated tube delivery results in tube retention within the ranges described for similar grommet-type tubes and complication rates consistent with traditional tube placement in the OR.


Asunto(s)
Iontoforesis , Otitis Media con Derrame , Niño , Humanos , Preescolar , Lidocaína , Ventilación del Oído Medio/métodos , Estudios Prospectivos , Membrana Timpánica , Otitis Media con Derrame/cirugía
15.
Clin Cancer Res ; 28(14): 3156-3169, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35552677

RESUMEN

PURPOSE: Paclitaxel (PTX) is one of the most potent and commonly used chemotherapies for breast and pancreatic cancer. Several ongoing clinical trials are investigating means of enhancing delivery of PTX across the blood-brain barrier for glioblastomas. Despite the widespread use of PTX for breast cancer, and the initiative to repurpose this drug for gliomas, there are no predictive biomarkers to inform which patients will likely benefit from this therapy. EXPERIMENTAL DESIGN: To identify predictive biomarkers for susceptibility to PTX, we performed a genome-wide CRISPR knockout (KO) screen using human glioma cells. The genes whose KO was most enriched in the CRISPR screen underwent further selection based on their correlation with survival in the breast cancer patient cohorts treated with PTX and not in patients treated with other chemotherapies, a finding that was validated on a second independent patient cohort using progression-free survival. RESULTS: Combination of CRISPR screen results with outcomes from patients with taxane-treated breast cancer led to the discovery of endoplasmic reticulum (ER) protein SSR3 as a putative predictive biomarker for PTX. SSR3 protein levels showed positive correlation with susceptibility to PTX in breast cancer cells, glioma cells, and in multiple intracranial glioma xenografts models. KO of SSR3 turned the cells resistant to PTX while its overexpression sensitized the cells to PTX. Mechanistically, SSR3 confers susceptibility to PTX through regulation of phosphorylation of ER stress sensor IRE1α. CONCLUSIONS: Our hypothesis generating study showed SSR3 as a putative biomarker for susceptibility to PTX, warranting its prospective clinical validation.


Asunto(s)
Antineoplásicos Fitogénicos , Biomarcadores Farmacológicos , Neoplasias Encefálicas , Neoplasias de la Mama , Proteínas de Unión al Calcio , Resistencia a Antineoplásicos , Glioblastoma , Glicoproteínas de Membrana , Paclitaxel , Receptores Citoplasmáticos y Nucleares , Receptores de Péptidos , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Proteínas de Unión al Calcio/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Endorribonucleasas/metabolismo , Femenino , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Humanos , Glicoproteínas de Membrana/genética , Ratones , Paclitaxel/uso terapéutico , Estudios Prospectivos , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Receptores de Péptidos/genética , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Nat Cancer ; 2(12): 1372-1386, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-35121903

RESUMEN

Only a subset of recurrent glioblastoma (rGBM) responds to anti-PD-1 immunotherapy. Previously, we reported enrichment of BRAF/PTPN11 mutations in 30% of rGBM that responded to PD-1 blockade. Given that BRAF and PTPN11 promote MAPK/ERK signaling, we investigated whether activation of this pathway is associated with response to PD-1 inhibitors in rGBM, including patients that do not harbor BRAF/PTPN11 mutations. Here we show that immunohistochemistry for ERK1/2 phosphorylation (p-ERK), a marker of MAPK/ERK pathway activation, is predictive of overall survival following adjuvant PD-1 blockade in two independent rGBM patient cohorts. Single-cell RNA-sequencing and multiplex immunofluorescence analyses revealed that p-ERK was mainly localized in tumor cells and that high-p-ERK GBMs contained tumor-infiltrating myeloid cells and microglia with elevated expression of MHC class II and associated genes. These findings indicate that ERK1/2 activation in rGBM is predictive of response to PD-1 blockade and is associated with a distinct myeloid cell phenotype.


Asunto(s)
Glioblastoma , Glioblastoma/tratamiento farmacológico , Humanos , Inmunoterapia , Sistema de Señalización de MAP Quinasas , Recurrencia Local de Neoplasia/tratamiento farmacológico , Fosforilación
17.
OTO Open ; 4(1): 2473974X20903125, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32133434

RESUMEN

OBJECTIVES: (1) To evaluate safety, tolerability, and technical success of lidocaine iontophoresis and a tympanostomy tube placement system for adults in an office setting and (2) to meet regulatory evidence requirements for new drugs and devices. STUDY DESIGN: Prospective, multicenter, single arm. SETTING: Patients were recruited in 8 community-based practices in the United States between June and September 2017. SUBJECTS AND METHODS: This study evaluated tympanic membrane anesthesia and tube placement in 30 adults. Anesthesia was achieved via iontophoresis of a lidocaine/epinephrine solution. Tube placement was conducted using an integrated myringotomy and tube delivery system. Tolerability of tube placement was measured using a patient-reported visual analog scale from 0 mm (no pain) to 100 mm (worst possible pain). Mean pain score was compared to a performance goal of 45 mm, where statistical superiority represents mild pain or less. Technical success and safety through 3 weeks postprocedure were evaluated. RESULTS: Twenty-nine (29/30, 96.7%) patients had tube(s) successfully placed in all indicated ears. One patient demonstrated inadequate tympanic membrane anesthesia, and no tube placement was attempted. The mean (SD) pain score of 9.4 (15.7) mm was statistically superior to the performance goal. There were no serious adverse events. Seven nonserious events were related to device, procedure, or drug: inadequate anesthesia (1), vertigo (1), and dizziness (1) at the time of procedure and ear discomfort (1), tube occlusion (2), and medial tube migration (1) postprocedure. CONCLUSION: Lidocaine iontophoresis provides acceptable tympanic membrane anesthesia for safe, tolerable, and successful in-office tube placement using an integrated myringotomy and tube delivery system.

18.
Laryngoscope ; 130 Suppl 4: S1-S9, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32160320

RESUMEN

OBJECTIVES/HYPOTHESIS: Evaluate technical success, tolerability, and safety of lidocaine iontophoresis and tympanostomy tube placement for children in an office setting. STUDY DESIGN: Prospective individual cohort study. METHODS: This prospective multicenter study evaluated in-office tube placement in children ages 6 months through 12 years of age. Anesthesia was achieved via lidocaine/epinephrine iontophoresis. Tube placement was conducted using an integrated and automated myringotomy and tube delivery system. Anxiolytics, sedation, and papoose board were not used. Technical success and safety were evaluated. Patients 5 to 12 years old self-reported tube placement pain using the Faces Pain Scale-Revised (FPS-R) instrument, which ranges from 0 (no pain) to 10 (very much pain). RESULTS: Children were enrolled into three cohorts with 68, 47, and 222 children in the Operating Room (OR) Lead-In, Office Lead-In, and Pivotal cohorts, respectively. In the Pivotal cohort, there were 120 and 102 children in the <5 and 5- to 12-year-old age groups, respectively, with a mean age of 2.3 and 7.6 years, respectively. Bilateral tube placement was indicated for 94.2% of children <5 and 88.2% of children 5 to 12 years old. Tubes were successfully placed in all indicated ears in 85.8% (103/120) of children <5 and 89.2% (91/102) of children 5 to 12 years old. Mean FPS-R score was 3.30 (standard deviation [SD] = 3.39) for tube placement and 1.69 (SD = 2.43) at 5 minutes postprocedure. There were no serious adverse events. Nonserious adverse events occurred at rates similar to standard tympanostomy procedures. CONCLUSIONS: In-office tube placement in selected patients can be successfully achieved without requiring sedatives, anxiolytics, or papoose restraints via lidocaine iontophoresis local anesthesia and an automated myringotomy and tube delivery system. LEVEL OF EVIDENCE: 2b Laryngoscope, 130:S1-S9, 2020.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/métodos , Iontoforesis/métodos , Ventilación del Oído Medio/métodos , Anestesia Local/métodos , Niño , Preescolar , Femenino , Humanos , Lactante , Lidocaína/administración & dosificación , Masculino , Estudios Prospectivos , Resultado del Tratamiento
19.
Front Pediatr ; 7: 446, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781523

RESUMEN

Fibrosis is an irreversible remodeling process characterized by the deposition of collagen in the extracellular matrix of various organs through a variety of pathologies in children, leading to the stiffening of healthy tissues and organ dysfunction. Despite the prevalence of fibrotic disease in children, large gaps exist in our understanding of the mechanisms that lead to fibrosis, and there are currently no therapies to treat or reverse it. We previously observed that castration significantly reduces fibrosis in the bladders of male mice that have been partially obstructed. Here, we investigated if the expression of androgen response genes were altered in mouse bladders after partial bladder outlet obstruction (PO). Using a QPCR microarray and QRTPCR we found that PO was sufficient to increase expression of the androgen response gene Nkx3.1. Consistent with this was an increase in the expression of NKX3.1 protein. Immunofluorescent antibody localization demonstrated nuclear NKX3.1 in most bladder cells after PO. We tested if genetic deletion of Nkx3.1 alters remodeling of the bladder wall after PO. After PO, Nkx3.1 KO/KO bladders underwent remodeling, demonstrating smaller bladder area, thickness, and bladder: body weight ratios than obstructed, wild type controls. Remarkably, Nkx3.1 KO/KO specifically affected histological parameters of fibrosis, including reduced collagen to muscle ratio. Loss of Nkx3.1 altered collagen and smooth muscle cytoskeletal gene expression following PO which supported our histologic findings. Together these findings indicated that after PO, Nkx3.1 expression is induced in the bladder and that it mediates important pathways that lead to tissue fibrosis. As Nkx3.1 is an androgen response gene, our data suggest a possible mechanism by which fibrosis is mediated in male mice and opens the possibility of a molecular pathway mediated by NKX3.1 that could explain sexual dimorphism in bladder fibrosis.

20.
Am J Clin Exp Urol ; 6(5): 189-196, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30510971

RESUMEN

The partial bladder outlet obstruction animal model (pBOO) is commonly used as a model for obstructive uropathy. Unfortunately, pBOO demonstrates variable degrees of obstruction requiring bladder weight (BW) or urodynamic studies to determine true obstruction. Our objective is to identify extent of obstruction by correlating early post-operative Void Stains on Paper (VSOP) assays with ultimate BW in mice. pBOO was performed on 32 mice 1- and 4-week VSOPs were quantified for mean voided volume (mVV). At 4 weeks, bladders were harvested and weighed. Correlation was evaluated through bivariate kernel density estimation and a Pearson correlation coefficient (SAS). Single variable histogram of the data established groups based on BWs and mVV. mVV's and bladder weights within group pairings were averaged and plotted to render a non-linear regression model. A significant correlation was found between 1-week mVVs and 4-week BWs upon bivariate analysis with a correlation coefficient of -0.758 (p = 0.0294). A non-linear regression of plotted data defined a statistically significant fit equation correlating 1-week mVV to 4-week BW. We demonstrate a novel method for forecasting degree of obstruction in pBOO based on 1-week post-operative VSOP mVV.

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