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1.
Lancet ; 400(10357): 1008-1019, 2022 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-36108657

RESUMEN

BACKGROUND: Merkel cell carcinoma is among the most aggressive and lethal of primary skin cancers, with a high rate of distant metastasis. Anti-programmed death receptor 1 (anti-PD-1) and programmed death ligand 1 (PD-L1) monotherapy is currently standard of care for unresectable, recurrent, or metastatic Merkel cell carcinoma. We assessed treatment with combined nivolumab plus ipilimumab, with or without stereotactic body radiotherapy (SBRT) in patients with advanced Merkel cell carcinoma as a first-line therapy or following previous treatment with anti-PD-1 and PD-L1 monotherapy. METHODS: In this randomised, open label, phase 2 trial, we randomly assigned adults from two cancer sites in the USA (one in Florida and one in Ohio) to group A (combined nivolumab and ipilimumab) or group B (combined nivolumab and ipilimumab plus SBRT) in a 1:1 ratio. Eligible patients were aged at least 18 years with histologically proven advanced stage (unresectable, recurrent, or stage IV) Merkel cell carcinoma, a minimum of two tumour lesions measureable by CT, MRI or clinical exam, and tumour tissue available for exploratory biomarker analysis. Patients were stratified by previous immune-checkpoint inhibitor (ICI) status to receive nivolumab 240 mg intravenously every 2 weeks plus ipilimumab 1 mg/kg intravenously every 6 weeks (group A) or the same schedule of combined nivolumab and ipilimumab with the addition of SBRT to at least one tumour site (24 Gy in three fractions at week 2; group B). Patients had to have at least two measurable sites of disease so one non-irradiated site could be followed for response. The primary endpoint was objective response rate (ORR) in all randomly assigned patients who received at least one dose of combined nivolumab and ipilimumab. ORR was defined as the proportion of patients with a complete response or partial response per immune-related Response Evaluation Criteria in Solid Tumours. Response was assessed every 12 weeks. Safety was assessed in all patients. This trial is registered with ClinicalTrials.gov, NCT03071406. FINDINGS: 50 patients (25 in both group A and group B) were enrolled between March 14, 2017, and Dec 21, 2021, including 24 ICI-naive patients (13 [52%] of 25 group A patients and 11 [44%] of 25 group B patients]) and 26 patients with previous ICI (12 [48%] of 25 group A patients and 14 [56%] of 25 group B patients]). One patient in group B did not receive SBRT due to concerns about excess toxicity. Median follow-up was 14·6 months (IQR 9·1-26·5). Two patients in group B were excluded from the analysis of the primary endpoint because the target lesions were irradiated and so the patients were deemed non-evaluable. Of the ICI-naive patients, 22 (100%) of 22 (95% CI 82-100) had an objective response, including nine (41% [95% CI 21-63]) with complete response. Of the patients who had previously had ICI exposure, eight (31%) of 26 patients (95% CI 15-52) had an objective response and four (15% [5-36]) had a complete response. No significant differences in ORR were observed between groups A (18 [72%] of 25 patients) and B (12 [52%] of 23 patients; p=0·26). Grade 3 or 4 treatment-related adverse events were observed in 10 (40%) of 25 patients in group A and 8 (32%) of 25 patients in group B. INTERPRETATION: First-line combined nivolumab and ipilimumab in patients with advanced Merkel cell carcinoma showed a high ORR with durable responses and an expected safety profile. Combined nivolumab and ipilimumab also showed clinical benefit in patients with previous anti-PD-1 and PD-L1 treatment. Addition of SBRT did not improve efficacy of combined nivolumab and ipilimumab. The combination of nivolumab and ipilimumab represents a new first-line and salvage therapeutic option for advanced Merkel cell carcinoma. FUNDING: Bristol Myers Squibb Rare Population Malignancy Program.


Asunto(s)
Carcinoma de Células de Merkel , Radiocirugia , Neoplasias Cutáneas , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Antígeno B7-H1 , Biomarcadores , Carcinoma de Células de Merkel/tratamiento farmacológico , Carcinoma de Células de Merkel/radioterapia , Humanos , Inhibidores de Puntos de Control Inmunológico , Ipilimumab , Nivolumab , Receptores de Muerte Celular , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/radioterapia
2.
Cancer Immunol Immunother ; 72(6): 1445-1460, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36469096

RESUMEN

Radiation therapy (RT) can prime and boost systemic anti-tumor effects via STING activation, resulting in enhanced tumor antigen presentation and antigen recognition by T cells. It is increasingly recognized that optimal anti-tumor immune responses benefit from coordinated cellular (T cell) and humoral (B cell) responses. However, the nature and functional relevance of the RT-induced immune response are controversial, beyond STING signaling, and agonistic interventions are lacking. Here, we show that B and CD4+ T cell accumulation at tumor beds in response to RT precedes the arrival of CD8+ T cells, and both cell types are absolutely required for abrogated tumor growth in non-irradiated tumors. Further, RT induces increased expression of 4-1BB (CD137) in both T and B cells; both in preclinical models and in a cohort of patients with small cell lung cancer treated with thoracic RT. Accordingly, the combination of RT and anti-41BB therapy leads to increased immune cell infiltration in the tumor microenvironment and significant abscopal effects. Thus, 4-1BB therapy enhances radiation-induced tumor-specific immune responses via coordinated B and T cell responses, thereby preventing malignant progression at unirradiated tumor sites. These findings provide a rationale for combining RT and 4-1bb therapy in future clinical trials.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Humanos , Neoplasias/radioterapia , Inmunoterapia , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral , Activación de Linfocitos , Microambiente Tumoral
3.
Mass Spectrom Rev ; 41(2): 352-369, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33491249

RESUMEN

Owing to the increasing environmental and climate changes globally, there is an increasing interest in the molecular-level understanding of environmental organic compound mixtures, that is, the pursuit of complete and detailed knowledge of the chemical compositions and related chemical reactions. Environmental organic molecule mixtures, including those in air, soil, rivers, and oceans, have extremely complex and heterogeneous chemical compositions. For their analyses, ultrahigh-resolution and sub-ppb level mass accuracy, achievable using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), are important. FT-ICR MS has been successfully used to analyze complex environmental organic molecule mixtures such as natural, soil, particulate, and dissolved organic matter. Despite its success, many limitations still need to be overcome. Sample preparation, ionization, structural identification, chromatographic separation, and data interpretation are some key areas that have been the focus of numerous studies. This review describes key developments in analytical techniques in these areas to aid researchers seeking to start or continue investigations for the molecular-level understanding of environmental organic compound mixtures.


Asunto(s)
Suelo , Análisis de Fourier , Espectrometría de Masas/métodos
4.
Rep Pract Oncol Radiother ; 26(1): 153-158, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34046227

RESUMEN

BACKGROUND: The aim was to demonstrate the feasibility and technique of gonadal sparing total body irradiation (TBI) with helical tomotherapy. Total body irradiation is a common part of the conditioning regimen prior to allogeneic stem cell transplantation. Shielding or dose-reduction to the gonads is often desired to preserve fertility, particularly in young patients undergoing transplant for non-malignant indications. Helical tomotherapy (HT) has been shown to be superior to traditional TBI delivery for organ at risk (OA R) doses and dose homogeneity. MATERIALS AND METHODS: We present two representative cases (one male and one female) to illustrate the feasibility of this technique, each of whom received 3Gy in a single fraction prior to allogeneic stem cell transplant for benign indications. The planning target volume (PTV) included the whole body with a subtraction of OA Rs including the lungs, heart, and brain (each contracted by 1cm) as well as the gonads (testicles expanded by 5 cm and ovaries expanded by 0.5 cm). RESULTS: For the male patient we achieved a homogeneity index of 1.35 with a maximum and median planned dose to the testes of 0.53 Gy and 0.35 Gy, respectively. In-vivo dosimetry demonstrated an actual received dose of 0.48 Gy. For the female patient we achieved a homogeneity index of 1.13 with a maximum and median planned dose to the ovaries of 1.66 Gy and 0.86 Gy, respectively. CONCLUSION: Gonadal sparing TBI is feasible and deliverable using HT in patients with non-malignant diseases requiring TBI as part of a pre-stem cell transplant conditioning regimen.

5.
Anal Chem ; 92(14): 9465-9471, 2020 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-32544315

RESUMEN

In this study, the reproducibility of crude oil analyzed with (+) atmospheric pressure photoionization ultrahigh resolution mass spectrometry was evaluated. Three sets of data were obtained at intervals of approximately a month for a span of three months. For each monthly data set, four oil samples were analyzed with four replicates in 1 day. The obtained 48 spectra were processed to examine the reproducibility of the class, double bond equivalent (DBE), and individual peak distributions. The reproducibility of the relative abundance was better than that of the absolute abundance. The distributions of major classes were consistent within the three sets with a less than 1% relative standard deviation (RSD). The DBE distribution for each data set was reproducible within 1% RSD, whereas the DBE distributions for the combined data sets had RSD values of 1%-6%. The RSD values were higher for minor components, suggesting that care must be taken in the use of minor values for quantitative or semiquantitative evaluation. The relative abundances of individual peaks in the major classes were reproducible within 1%-3% RSD for each data set. However, the RSD values of the combined data sets were over 10%, even for abundant peaks. The smaller RSD of the class and DBE distributions than that of individual peaks for combined data sets strongly suggest that variations observed from individuals were caused by random errors. The data presented in this study provide guidelines for evaluating petroleomic data obtained in the laboratory at different times or laboratories.

6.
Anal Bioanal Chem ; 412(1): 243-255, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31844918

RESUMEN

We herein report the optimization and application of silver cationization (Ag+) in combination with laser desorption ionization (LDI) ultrahigh-resolution mass spectrometry (UHR-MS) to determine the structures of the sulfur-containing compounds present in heavy crude oil. A number of sulfur-containing model compounds were used to optimize the positive-ion mode LDI-MS conditions in the presence of a silver-complexing agent. Under the optimized LDI conditions, sulfur-rich heavy oil fractions were treated with the silver salt, where Ag+ coordinated with the sulfur atoms to speciate the sulfur species. The obtained results suggested that benzothiophenic, naphtheno-non-aromatic sulfides, and non-aromatic thiols were the major components present in the analyzed oil sample. Graphical abstract.

7.
Proc Natl Acad Sci U S A ; 114(30): 7923-7928, 2017 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-28696307

RESUMEN

Structural deformation and collapse in metal-organic frameworks (MOFs) can lead to loss of long-range order, making it a challenge to model these amorphous materials using conventional computational methods. In this work, we show that a structure-property map consisting of simulated data for crystalline MOFs can be used to indirectly obtain adsorption properties of structurally deformed MOFs. The structure-property map (with dimensions such as Henry coefficient, heat of adsorption, and pore volume) was constructed using a large data set of over 12000 crystalline MOFs from molecular simulations. By mapping the experimental data points of deformed SNU-200, MOF-5, and Ni-MOF-74 onto this structure-property map, we show that the experimentally deformed MOFs share similar adsorption properties with their nearest neighbor crystalline structures. Once the nearest neighbor crystalline MOFs for a deformed MOF are selected from a structure-property map at a specific condition, then the adsorption properties of these MOFs can be successfully transformed onto the degraded MOFs, leading to a new way to obtain properties of materials whose structural information is lost.

8.
Anal Chem ; 91(12): 7690-7697, 2019 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-31117404

RESUMEN

In this study, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), combined with quadrupolar detection (QPD), was applied for online liquid chromatography (LC) MS analysis of natural organic matter (NOM). Although FT-ICR MS has emerged as an important analytical technique to study NOM, there are few previous reports on online LC FT-ICR MS analysis of NOM due to the long acquisition time (2-8 s) required to obtain high-resolution mass spectra. The QPD technique provides a critical advantage over the conventional dipolar detection (DPD) technique for LC-MS analysis because a spectrum with the same resolving power can be obtained in approximately half the acquisition time. QPD FT-ICR MS provides resolving powers ( mΔm50% ) of ∼300000 and 170000 at m/ z 400 with acquisition times per scan of 1.2 and 0.8 s, respectively. The reduced acquisition time per scan allows increased number of acquisitions in a given LC analysis time, resulting in improved signal to noise ( S/ N) ratio and dynamic range in comparison to conventional methods. For example, 40% and 100% increases in the number of detected peaks were obtained with LC QPD FT-ICR MS, in comparison to conventional LC DPD FT-ICR MS and direct-injection FT-ICR MS. It is also possible to perform more quantitative comparison and molecular level investigation of NOMs with 2 µg of a NOM sample. The data presented herein demonstrate a proof of principle that QPD combined with LC FT-ICR MS is a sensitive analytical technique that can provide comprehensive information about NOM.

9.
Anal Bioanal Chem ; 411(27): 7303-7313, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31511945

RESUMEN

In this work, laser desorption ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry (LDI-FTICRMS) was used to investigate the molecular composition of a peat fire and laboratory heated soil organic matter (SOM). SOM isolated from soils obtained from unburned and burned sites at Central Kalimantan, Indonesia, were analyzed with LDI-FTICRMS. About 7500 peaks were found and assigned with molecular formulas for each mass spectrum. SOM isolated from fire-affected soil sites are relatively more abundant in low oxygenated classes (e.g., O1-O5) and thermally stable compounds, including condensed hydrocarbon and nitrogen heterocyclic compounds. Abundances of highly condensed hydrocarbon compounds with carbon number > 30 were increased for the fire-affected SOM. In vivo heating experiments were conducted for SOM extracted from unburned sites, and the prepared SOMs were analyzed with LDI-FTICRMS. Overall, the same trend of change at the molecular level was observed from both the laboratory heated and the peat fire-affected SOM samples. In addition, it was observed that heat caused the degradation of SOM, generating lignin and tannin-type molecules. It was hypothesized that they were formed by thermal degradation of high molecular weight SOM. All the information presented in this study was obtained by consuming ~ 5 µg of sample. Therefore, this study shows that LDI-FTICRMS is a sensitive analytical technique that is effective in obtaining molecular level information of SOM. Graphical abstract.


Asunto(s)
Ciclotrones , Análisis de Fourier , Espectrometría de Masas/métodos , Suelo/química , Incendios , Indonesia
10.
Lancet Oncol ; 18(5): e266-e273, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28456586

RESUMEN

Radiotherapy has long been the mainstay of treatment for patients with head and neck cancer and has traditionally involved a stage-dependent strategy whereby all patients with the same TNM stage receive the same therapy. We believe there is a substantial opportunity to improve radiotherapy delivery beyond just technological and anatomical precision. In this Series paper, we explore several new ideas that could improve understanding of the phenotypic and genotypic differences that exist between patients and their tumours. We discuss how exploiting these differences and taking advantage of precision medicine tools-such as genomics, radiomics, and mathematical modelling-could open new doors to personalised radiotherapy adaptation and treatment. We propose a new treatment shift that moves away from an era of empirical dosing and fractionation to an era focused on the development of evidence to guide personalisation and biological adaptation of radiotherapy. We believe these approaches offer the potential to improve outcomes and reduce toxicity.


Asunto(s)
Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/radioterapia , Medicina de Precisión , Radioterapia/métodos , Biomarcadores de Tumor/genética , Terapia Combinada , Genotipo , Neoplasias de Cabeza y Cuello/terapia , Humanos , Inmunoterapia , Modelos Teóricos , Fenotipo , Tolerancia a Radiación/genética , Dosificación Radioterapéutica
11.
J Neurooncol ; 133(2): 331-338, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28466250

RESUMEN

Anti-PD-1/PD-L1 therapies have demonstrated activity in patients with advanced stage non-small cell lung cancer (NSCLC). However, little is known about the safety and feasibility of patients receiving anti-PD-1/PD-L1 therapy and stereotactic radiation for the treatment of brain metastases. Data were analyzed retrospectively from NSCLC patients treated with stereotactic radiation either before, during or after anti-PD-1/PD-L1 therapy with nivolumab (anti-PD-1) or durvalumab (anti-PD-L1). Seventeen patients treated with stereotactic radiosurgery (SRS) or fractionated stereotactic radiation therapy (FSRT) to 49 brain metastases over 21 sessions were identified. Radiation was administered prior to, during and after anti-PD-1/PD-L1 therapy in 22 lesions (45%), 13 lesions (27%), and 14 lesions (29%), respectively. The 6 months Kaplan-Meier (KM) distant brain control rate was 48% following stereotactic radiation. Six and 12 month KM rates of OS from the date of stereotactic radiation and the date of cranial metastases diagnosis were 48/41% and 81/51%, respectively. The 6 month rate of distant brain control following stereotactic radiation for patients treated with stereotactic radiation during or prior to anti-PD-1/PD-L1 therapy was 57% compared to 0% among patients who received anti-PD-1/PD-L1 therapy before stereotactic radiation (p = 0.05). A Karnofsky Performance Status (KPS) of <90 was found to be predictive of worse OS following radiation treatment on both univariate and multivariate analyses (MVA, p = 0.01). In our series, stereotactic radiation to NSCLC brain metastases was well tolerated in patients who received anti-PD-1/PD-L1 therapy. Prospective evaluation to determine how these two modalities can be used synergistically to improve distant brain control and OS is warranted.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/terapia , Irradiación Craneana/métodos , Receptor de Muerte Celular Programada 1/inmunología , Adulto , Anciano , Neoplasias Encefálicas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
12.
Ann Surg Oncol ; 23(11): 3572-3578, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27251134

RESUMEN

BACKGROUND: Following wide excision of Merkel cell carcinoma (MCC), postoperative radiation therapy (RT) is typically recommended. Controversy remains as to whether RT can be avoided in selected cases, such as those with negative margins. Additionally, there is evidence that RT can influence survival. METHODS: We included 171 patients treated for non-metastatic MCC from 1994 through 2012 at a single institution. Patients without pathologic nodal evaluation (clinical N0 disease) were excluded to reflect modern treatment practice. The endpoints included local control (LC), locoregional control (LRC), disease-free survival (DFS), overall survival (OS), and disease-specific survival (DSS). RESULTS: Median follow-up was 33 months. Treatment with RT was associated with improved 3-year LC (91.2 vs. 76.9 %, respectively; p = 0.01), LRC (79.5 vs. 59.1 %; p = 0.004), DFS (57.0 vs. 30.2 %; p < 0.001), and OS (73 vs. 66 %; p = 0.02), and was associated with improved 3-year DSS among node-positive patients (76.2 vs. 48.1 %; p = 0.035), but not node-negative patients (90.1 vs. 80.8 %; p = 0.79). On multivariate analysis, RT was associated with improved LC [hazard ratio (HR) 0.18, 95 % confidence interval (CI) 0.07-0.46; p < 0.001], LRC (HR 0.28, 95 % CI 0.14-0.56; p < 0.001), DFS (HR 0.42, 95 % CI 0.26-0.70; p = 0.001), OS (HR 0.53, 95 % CI 0.31-0.93; p = 0.03), and DSS (HR 0.42, 95 % CI 0.26-0.70; p = 0.001). Patients with negative margins had significant improvements in 3-year LC (90.1 vs. 75.4 %; p < 0.001) with RT. Deaths not attributable to MCC were relatively evenly distributed between the RT and no RT groups (28.5 and 29.3 % of patients, respectively). CONCLUSIONS: RT for MCC was associated with improved LRC and survival. RT appeared to be beneficial regardless of margin status.


Asunto(s)
Carcinoma de Células de Merkel/radioterapia , Carcinoma de Células de Merkel/cirugía , Escisión del Ganglio Linfático , Neoplasias Cutáneas/radioterapia , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células de Merkel/secundario , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Radioterapia Adyuvante , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/patología , Tasa de Supervivencia
13.
Proc Natl Acad Sci U S A ; 109(19): E1143-52, 2012 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-22493234

RESUMEN

Obesity triggers a low-grade systemic inflammation, which plays an important role in the development of obesity-associated metabolic diseases. In searching for links between lipid accumulation and chronic inflammation, we examined invariant natural killer T (iNKT) cells, a subset of T lymphocytes that react with lipids and regulate inflammatory responses. We show that iNKT cells respond to dietary lipid excess and become activated before or at the time of tissue recruitment of inflammatory leukocytes, and that these cells progressively increase proinflammatory cytokine production in obese mice. Such iNKT cells skew other leukocytes toward proinflammatory cytokine production and induce an imbalanced proinflammatory cytokine environment in multiple tissues. Further, iNKT cell deficiency ameliorates tissue inflammation and provides protection against obesity-induced insulin resistance and hepatic steatosis. Conversely, chronic iNKT cell stimulation using a canonical iNKT cell agonist exacerbates tissue inflammation and obesity-associated metabolic disease. These findings place iNKT cells into the complex network linking lipid excess to inflammation in obesity and suggest new therapeutic avenues for obesity-associated metabolic disorders.


Asunto(s)
Hígado Graso/inmunología , Galactosilceramidas/fisiología , Inflamación/inmunología , Resistencia a la Insulina/inmunología , Células T Asesinas Naturales/inmunología , Obesidad/inmunología , Tejido Adiposo Blanco/inmunología , Tejido Adiposo Blanco/metabolismo , Tejido Adiposo Blanco/patología , Animales , Antígenos CD1d/genética , Antígenos CD1d/inmunología , Antígenos CD1d/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Células Cultivadas , Citocinas/inmunología , Citocinas/metabolismo , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/inmunología , Hígado Graso/genética , Femenino , Citometría de Flujo , Galactosilceramidas/administración & dosificación , Galactosilceramidas/inmunología , Inflamación/genética , Mediadores de Inflamación/inmunología , Mediadores de Inflamación/metabolismo , Resistencia a la Insulina/genética , Lípidos/administración & dosificación , Lípidos/inmunología , Activación de Linfocitos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células T Asesinas Naturales/metabolismo , Obesidad/genética
14.
Cancer Immunol Immunother ; 63(10): 1009-21, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24943275

RESUMEN

There is a significant body of evidence demonstrating that radiation therapy (XRT) enhances the effect of immune therapy. However, the precise mechanisms by which XRT potentiates the immunotherapy of cancer remain elusive. Here, we report that XRT potentiates the effect of immune therapy via induction of autophagy and resultant trafficking of mannose-6-phopsphate receptor (MPR) to the cell surface. Irradiation of different tumor cells caused substantial up-regulation of MPR on the cell surface in vitro and in vivo. Down-regulation of MPR in tumor cells with shRNA completely abrogated the combined effect of XRT and immunotherapy (CTLA4 antibody) in B16F10-bearing mice without changes in the tumor-specific responses of T cells. Radiation-induced MPR up-regulation was the result of redistribution of the receptor to the cell surface. This effect was caused by autophagy with redirection of MPR to autophagosomes in a clathrin-dependent manner. In autophagosomes, MPR lost its natural ligands, which resulted in subsequent trafficking of empty receptor(s) back to the surface. Together, our data demonstrated a novel mechanism by which XRT can enhance the effect of immunotherapy and the molecular mechanism of this process.


Asunto(s)
Inmunoterapia/métodos , Neoplasias Experimentales/terapia , Receptor IGF Tipo 2/metabolismo , Animales , Autofagia/inmunología , Autofagia/efectos de la radiación , Línea Celular Tumoral , Terapia Combinada , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/radioterapia , Distribución Aleatoria , Regulación hacia Arriba
16.
J Immunol ; 186(12): 6683-92, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21572029

RESUMEN

Cytoplasmic Ags derived from viruses, cytosolic bacteria, tumors, and allografts are presented to T cells by MHC class I or class II molecules. In the case of class II-restricted Ags, professional APCs acquire them during uptake of dead class II-negative cells and present them via a process called indirect presentation. It is generally assumed that the cytosolic Ag-processing machinery, which supplies peptides for presentation by class I molecules, plays very little role in indirect presentation of class II-restricted cytoplasmic Ags. Remarkably, upon testing this assumption, we found that proteasomes, TAP, and endoplasmic reticulum-associated aminopeptidase associated with Ag processing, but not tapasin, partially destroyed or removed cytoplasmic class II-restricted Ags, such that their inhibition or deficiency led to dramatically increased Th cell responses to allograft (HY) and microbial (Listeria monocytogenes) Ags, both of which are indirectly presented. This effect was neither due to enhanced endoplasmic reticulum-associated degradation nor competition for Ag between class I and class II molecules. From these findings, a novel model emerged in which the cytosolic Ag-processing machinery regulates the quantity of cytoplasmic peptides available for presentation by class II molecules and, hence, modulates Th cell responses.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/inmunología , Aminopeptidasas/inmunología , Presentación de Antígeno/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Complejo de la Endopetidasa Proteasomal/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Antígenos Bacterianos/inmunología , Citoplasma/inmunología , Retículo Endoplásmico , Listeria monocytogenes/inmunología , Trasplante Homólogo/inmunología
17.
Nat Commun ; 14(1): 1573, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949064

RESUMEN

While STING-activating agents have shown limited efficacy in early-phase clinical trials, multiple lines of evidence suggest the importance of tumor cell-intrinsic STING function in mediating antitumor immune responses. Although STING signaling is impaired in human melanoma, its restoration through epigenetic reprogramming can augment its antigenicity and T cell recognition. In this study, we show that reversal of methylation silencing of STING in murine melanoma cell lines using a clinically available DNA methylation inhibitor can improve agonist-induced STING activation and type-I IFN induction, which, in tumor-bearing mice, can induce tumor regression through a CD8+ T cell-dependent immune response. These findings not only provide mechanistic insight into how STING signaling dysfunction in tumor cells can contribute to impaired responses to STING agonist therapy, but also suggest that pharmacological restoration of STING signaling through epigenetic reprogramming might improve the therapeutic efficacy of STING agonists.


Asunto(s)
Antineoplásicos , Interferón Tipo I , Melanoma , Animales , Ratones , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Inmunidad , Interferón Tipo I/metabolismo , Epigénesis Genética
18.
Technol Cancer Res Treat ; 22: 15330338231180779, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37287260

RESUMEN

Introduction: High-dose total body irradiation (TBI) is often part of myeloablative conditioning in acute leukemia. Modern volumetric modulated arc therapy (VMAT)-based plans employ arcs to the inferior-most portion of the body that can be simulated in a head-first position and use 2D planning for the inferior body which can result in heterogeneous doses. Here, we describe our institution's unique protocol for delivering high-dose TBI entirely with VMAT and retrospectively compare dosimetric outcomes with helical tomotherapy (HT) plans. Additionally, we describe our method of oropharyngeal mucosal sparing that was implemented after fatal mucositis occurred in two patients. Methods: Thirty-one patients were simulated and treated in head-first (HFS) and feet-first (FFS) orientations. Patients were treated with VMAT (n = 26) or HT (n = 5). In VMAT plans, to synchronize doses between the orientations, images were deformably registered and the HFS dose was transferred to the FFS plan and used as a background dose when optimizing plans. Six to eight isocenters with two arcs per isocenter were generated. HT was delivered with an established technique. Patients were treated to 13.2 Gy over eight twice daily fractions. Dosimetric outcomes and toxicities were retrospectively compared. Results: Prescription dose and organ at risk (OAR) constraints were met for all patients. Lower lung doses were achieved with VMAT relative to HT plans (7.4 vs 7.7 Gy, P = .009). Statistically significant improvement in mucositis was not achieved after adopting a mucosal-sparing technique, however lower doses to the oropharyngeal mucosal were achieved (6.9 vs 14.1 Gy, P = .009), and no further mucositis-related deaths occurred. Conclusions: This full-body VMAT method of TBI achieves dose goals, eliminates risk of heterogenous doses within the femur, and demonstrates that selective OAR sparing with the purpose of reducing TBI-related morbidity and mortality is possible at any institution with a VMAT-capable linear accelerator.


Asunto(s)
Radioterapia de Intensidad Modulada , Humanos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Irradiación Corporal Total/efectos adversos , Dosificación Radioterapéutica , Estudios de Factibilidad , Estudios Retrospectivos , Planificación de la Radioterapia Asistida por Computador/métodos , Órganos en Riesgo/efectos de la radiación
19.
Int J Radiat Oncol Biol Phys ; 116(4): 837-848, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36657497

RESUMEN

PURPOSE: We hypothesized that concurrent ipilimumab with chemoradiationtherapy (chemoRT) followed by maintenance nivolumab would be safe for patients with unresectable stage III non-small cell lung cancer (NSCLC). We aimed to assess the safety (phase 1) and the 12-month progression-free survival (PFS) (phase 2) in a multi-institution prospective trial. METHODS AND MATERIALS: Eligible patients had unresectable stage III NSCLC. The treatment included platinum doublet chemotherapy with concurrent thoracic radiation therapy to 60 Gy in 30 fractions and ipilimumab (1 mg/kg) delivered during weeks 1 and 4. After chemoRT, maintenance nivolumab (480 mg) was given every 4 weeks for up to 12 cycles. Adverse events (AEs) were assessed according to the Common Terminology Criteria for Adverse Events, version 5.0. Survival analyses were performed with Kaplan Meier (KM) methods and log-rank tests. RESULTS: The trial was discontinued early after enrolling 19 patients without proceeding to the phase 2 component because of unacceptable toxicity. Sixteen patients (84%) had grade ≥3 (G3+) possible treatment-related toxicity, most commonly pulmonary AEs (n = 8, 42%). Fourteen patients (74%) discontinued study therapy early because of AEs (n = 12, 63%) or patient choice (n = 2, 11%). Eleven patients (58%) experienced G2+ pulmonary toxicity with median time to onset 4.1 months (95% CI 2.6-not reached [NR]), and 12-month freedom from G2+ pulmonary toxicity 37% (95% CI, 16-59). Five patients had G5 AEs, including 3 with G5 pulmonary AEs (1 respiratory failure with pneumonitis and pulmonary embolism, 1 pneumonia/chronic obstructive pulmonary disease exacerbation, 1 pulmonary fibrosis). Despite toxicities, the median PFS was 19.2 months (95% CI 6.1-NR) and the median overall survival was NR (95% CI 6.1-NR) with median follow-up of 30.1 months by the reverse KM method. CONCLUSIONS: Concurrent ipilimumab with chemoRT for unresectable stage III NSCLC is associated with pulmonary toxicity that may limit opportunities for improved outcomes. Future studies aiming to incorporate ipilimumab or other anti-CTLA4 therapies into management of unresectable stage III NSCLC should consider careful measures to minimize toxicity risk.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Melanoma , Humanos , Nivolumab/efectos adversos , Ipilimumab/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Melanoma/patología , Estudios Prospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Estadificación de Neoplasias , Neoplasias Pulmonares/tratamiento farmacológico
20.
Exp Mol Med ; 54(3): 207-215, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35296782

RESUMEN

It is well known that metabolism underlies T cell differentiation and functions. The pathways regulating T cell metabolism and function are interconnected, and changes in T cell metabolic activity directly impact the effector functions and fate of T cells. Thus, understanding how metabolic pathways influence immune responses and ultimately affect disease progression is paramount. Epigenetic and posttranslational modification mechanisms have been found to control immune responses and metabolic reprogramming. Sirtuins are NAD+-dependent histone deacetylases that play key roles during cellular responses to a variety of stresses and have recently been reported to have potential roles in immune responses. Therefore, sirtuins are of significant interest as therapeutic targets to treat immune-related diseases and enhance antitumor immunity. This review aims to illustrate the potential roles of sirtuins in different subtypes of T cells during the adaptive immune response.


Asunto(s)
Sirtuinas , Linfocitos T , Diferenciación Celular , Humanos , Redes y Vías Metabólicas , Procesamiento Proteico-Postraduccional , Sirtuinas/metabolismo , Linfocitos T/metabolismo
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