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1.
Cancer Res Commun ; 4(3): 911-918, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38477596

RESUMO

Lack of robust activation of Stimulator of Interferon Genes (STING) pathway and subsequent induction of type I IFN responses is considered a barrier to antitumor immunity in acute myeloid leukemia (AML). Using common human AML cell lines as in vitro tools to evaluate the efficacy of novel STING agonists, we found most AML lines to be poor producers of IFNs upon exposure to extremely potent agonists, suggesting cell-intrinsic suppression of STING signaling may occur. We observed unexpected patterns of response that did not correlate with levels of STING pathway components or of known enzymes associated with resistance. To identify a genetic basis for these observations, we cloned and sequenced STING from the cDNA of human AML cell lines and found both frequent mutations and deviations from normal RNA splicing. We identified two novel spliced isoforms of STING in these lines and validated their expression in primary human AML samples. When transduced into reporter cells, these novel STING isoforms exhibited complete insensitivity to agonist stimulation. These observations identify alternative splicing as a mechanism of STING pathway suppression and suggest that most AML silences the STING pathway through direct modification rather than through engagement of external inhibitory factors. SIGNIFICANCE: We find that AML acquires resistance to innate immune activation via the STING pathway through aberrant splicing of the STING transcript including two novel forms described herein that act as dominant negatives. These data broaden understanding of how cancers evolve STING resistance, and suggest that the AML tumor microenvironment, not the cancer cell, should be the target of therapeutic interventions to activate STING.


Assuntos
Interferon Tipo I , Leucemia Mieloide Aguda , Humanos , Isoformas de Proteínas/genética , Leucemia Mieloide Aguda/genética , Processamento Alternativo/genética , Interferon Tipo I/genética , Linhagem Celular , Microambiente Tumoral
3.
JCI Insight ; 9(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-37988164

RESUMO

We previously showed that ablation of tumor hypoxia can sensitize tumors to immune checkpoint blockade (ICB). Here, we used a Kras+/G12D TP53+/R172H Pdx1-Cre-derived (KPC-derived) model of pancreatic adenocarcinoma to examine the tumor response and adaptive resistance mechanisms involved in response to 2 established methods of hypoxia-reducing therapy: the hypoxia-activated prodrug TH-302 and vascular endothelial growth factor receptor 2 (VEGFR-2) blockade. The combination of both modalities normalized tumor vasculature, increased DNA damage and cell death, and delayed tumor growth. In contrast with prior cancer models, the combination did not alleviate overall tissue hypoxia or sensitize these KPC tumors to ICB therapy despite qualitative improvements to the CD8+ T cell response. Bulk tumor RNA sequencing, flow cytometry, and adoptive myeloid cell transfer suggested that treated tumor cells increased their capacity to recruit granulocytic myeloid-derived suppressor cells (G-MDSCs) through CCL9 secretion. Blockade of the CCL9/CCR1 axis could limit G-MDSC migration, and depletion of Ly6G-positive cells could sensitize tumors to the combination of TH-302, anti-VEGFR-2, and ICB. Together, these data suggest that pancreatic tumors modulate G-MDSC migration as an adaptive response to vascular normalization and that these immunosuppressive myeloid cells act in a setting of persistent hypoxia to maintain adaptive immune resistance.


Assuntos
Adenocarcinoma , Células Supressoras Mieloides , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patologia , Adenocarcinoma/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Hipóxia/metabolismo
4.
J Neurooncol ; 165(1): 161-169, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37878192

RESUMO

BACKGROUND: Neurocognitive deficits are common in pediatric brain tumor survivors. The use of single nucleotide polymorphism (SNP) analysis in DNA repair genes may identify children treated with radiation therapy for brain tumors at increased risk for treatment toxicity and adverse neurocognitive outcomes. MATERIALS: The Human 660W-Quad v1.0 DNA BeadChip analysis (Illumina) was used to evaluate 1048 SNPs from 59 DNA repair genes in 46 subjects. IQ testing was measured by the Wechsler Intelligence Scale for Children. Linear regression was used to identify the 10 SNPs with the strongest association with IQ scores while adjusting for radiation type. RESULTS: The low vs high IQ patient cohorts were well matched for time from first treatment to most recent IQ, first treatment age, sex, and treatments received. 5 SNPs on 3 different genes (CYP29, XRCC1, and BRCA1) and on 3 different chromosomes (10, 19, and 17) had the strongest association with most recent IQ score that was not modified by radiation type. Furthermore, 5 SNPs on 4 different genes (WRN, NR3C1, ERCC4, RAD51L1) on 4 different chromosomes (8, 5, 16, 14) had the strongest association with change in IQ independent of radiation type, first IQ, and years between IQ measures. CONCLUSIONS: SNPs offer the potential to predict adverse neurocognitive outcomes in pediatric brain tumor survivors. Our results require validation in a larger patient cohort. Improving the ability to identify children at risk of treatment related neurocognitive deficits could allow for better treatment stratification and early cognitive interventions.


Assuntos
Neoplasias Encefálicas , Criança , Humanos , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Testes de Inteligência , Sobreviventes , Irradiação Craniana/efeitos adversos , Testes Neuropsicológicos , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
5.
Res Sq ; 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37609195

RESUMO

Purpose: Neurocognitive deficits are common in pediatric brain tumor survivors. The use of single nucleotide polymorphism (SNP) analysis in DNA repair genes may identify children treated with radiation therapy for brain tumors at increased risk for treatment toxicity and adverse neurocognitive outcomes. Methods: The Human 660W-Quad v1.0 DNA BeadChip analysis (Illumina) was used to evaluate 1048 SNPs from 59 DNA repair genes in 46 subjects. IQ testing was measured by the Wechsler Intelligence Scale for Children. Linear regression was used to identify the 10 SNPs with the strongest association with IQ scores while adjusting for radiation type. Results: The low vs high IQ patient cohorts were well matched for time from first treatment to most recent IQ, first treatment age, gender, and treatments received. 5 SNPs on 3 different genes (CYP29, XRCC1, and BRCA1) and on 3 different chromosomes (10, 19, and 17) had the strongest association with most recent IQ score that was not modified by radiation type. Furthermore, 5 SNPs on 4 different genes (WRN, NR3C1, ERCC4, RAD51L1) on 4 different chromosomes (8, 5, 16, 14) had the strongest association with change in IQ independent of radiation type, first IQ, and years between IQ measures. Conclusions: SNP polymorphisms offer potential to predict adverse neurocognitive outcomes in pediatric brain tumor survivors. Our results require validation in a larger patient cohort. Improving the ability to identify children at risk of treatment related neurocognitive deficits could allow for better treatment stratification and early cognitive interventions.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37452796

RESUMO

PURPOSE: Kidney injury is a known late and potentially devastating complication of abdominal radiation therapy (RT) in pediatric patients. A comprehensive Pediatric Normal Tissue Effects in the Clinic review by the Genitourinary (GU) Task Force aimed to describe RT dose-volume relationships for GU dysfunction, including kidney, bladder, and hypertension, for pediatric malignancies. The effect of chemotherapy was also considered. METHODS AND MATERIALS: We conducted a comprehensive PubMed search of peer-reviewed manuscripts published from 1990 to 2017 for investigations on RT-associated GU toxicities in children treated for cancer. We retrieved 3271 articles with 100 fulfilling criteria for full review, 24 with RT dose data and 13 adequate for modeling. Endpoints were heterogenous and grouped according to National Kidney Foundation: grade ≥1, grade ≥2, and grade ≥3. We modeled whole kidney exposure from total body irradiation (TBI) for hematopoietic stem cell transplant and whole abdominal irradiation (WAI) for patients with Wilms tumor. Partial kidney tolerance was modeled from a single publication from 2021 after the comprehensive review revealed no usable partial kidney data. Inadequate data existed for analysis of bladder RT-associated toxicities. RESULTS: The 13 reports with long-term GU outcomes suitable for modeling included 4 on WAI for Wilms tumor, 8 on TBI, and 1 for partial renal RT exposure. These reports evaluated a total of 1191 pediatric patients, including: WAI 86, TBI 666, and 439 partial kidney. The age range at the time of RT was 1 month to 18 years with medians of 2 to 11 years in the various reports. In our whole kidney analysis we were unable to include chemotherapy because of the heterogeneity of regimens and paucity of data. Age-specific toxicity data were also unavailable. Wilms studies occurred from 1968 to 2011 with mean follow-ups 8 to 15 years. TBI studies occurred from 1969 to 2004 with mean follow-ups of 4 months to 16 years. We modeled risk of dysfunction by RT dose and grade of toxicity. Normal tissue complication rates ≥5%, expressed as equivalent doses, 2 Gy/fx for whole kidney exposures occurred at 8.5, 10.2, and 14.5 Gy for National Kidney Foundation grades ≥1, ≥2, and ≥3, respectively. Conventional Wilms WAI of 10.5 Gy in 6 fx had risks of ≥grade 2 toxicity 4% and ≥grade 3 toxicity 1%. For fractionated 12 Gy TBI, those risks were 8% and <3%, respectively. Data did not support whole kidney modeling with chemotherapy. Partial kidney modeling from 439 survivors who received RT (median age, 7.3 years) demonstrated 5 or 10 Gy to 100% kidney gave a <5% risk of grades 3 to 5 toxicity with 1500 mg/m2 carboplatin or no chemo. With 480 mg/m2 cisplatin, a 3% risk of ≥grade 3 toxicity occurred without RT and a 5% risk when 26% kidney received ≥10 Gy. With 63 g/m2 of ifosfamide, a 5% risk of ≥grade 3 toxicity occurred with no RT, and a 10% toxicity risk occurred when 42% kidney received ≥10 Gy. CONCLUSIONS: In patients with Wilms tumor, the risk of toxicity from 10.5 Gy of WAI is low. For 12 Gy fractionated TBI with various mixtures of chemotherapy, the risk of severe toxicity is low, but low-grade toxicity is not uncommon. Partial kidney data are limited and toxicity is associated heavily with the use of nephrotoxic chemotherapeutic agents. Our efforts demonstrate the need for improved data gathering, systematic follow-up, and reporting in future clinical studies. Current radiation dose used for Wilms tumor and TBI appear to be safe; however, efforts in effective kidney-sparing TBI and WAI regimens may reduce the risks of renal injury without compromising cure.

9.
AJR Am J Roentgenol ; 220(2): 283-295, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36129222

RESUMO

BACKGROUND. Iterative reconstruction (IR) techniques are susceptible to contrast-dependent spatial resolution, limiting overall radiation dose reduction potential. Deep learning image reconstruction (DLIR) may mitigate this limitation. OBJECTIVE. The purpose of our study was to evaluate low-contrast detectability performance and radiation-saving potential of a DLIR algorithm in comparison with filtered back projection (FBP) and IR using a human multireader noninferiority study design and task-based observer modeling. METHODS. A dual-phantom construct, consisting of a low-contrast detectability module (21 low-contrast hypoattenuating objects in seven sizes [2.4-10.0 mm] and three contrast levels [-15, -10, -5 HU] embedded within liver-equivalent background) and a phantom, was imaged at five radiation exposures (CTDIvol range, 1.4-14.0 mGy; size-specific dose estimate, 2.5-25.0 mGy; 90%-, 70%-, 50%-, and 30%-reduced radiation levels and full radiation level) using an MDCT scanner. Images were reconstructed using FBP, hybrid IR (ASiR-V), and DLIR (TrueFidelity). Twenty-four readers of varying experience levels evaluated images using a two-alternative forced choice. A task-based observer model (detectability index [d']) was calculated. Reader performance was estimated by calculating the AUC using a noninferiority method. RESULTS. Compared with FBP and IR methods at routine radiation levels, DLIR medium and DLIR high settings showed noninferior performance through a 90% radiation reduction (except DLIR medium setting at 70% reduced level). The IR method was non-inferior to routine radiation FBP only for 30% and 50% radiation reductions. No significant difference in d' was observed between routine radiation FBP and DLIR high setting through a 70% radiation reduction. Reader experience was not correlated with diagnostic accuracy (R2 = 0.005). CONCLUSION. Compared with FBP or IR methods at routine radiation levels, certain DLIR algorithm weightings yielded noninferior low-contrast detectability with radiation reductions of up to 90% as measured by 24 human readers and up to 70% as assessed by a task-based observer model. CLINICAL IMPACT. DLIR has substantial potential to preserve contrast-dependent spatial resolution for the detection of hypoattenuating lesions at decreased radiation levels in a phantom model, addressing a major shortcoming of current IR techniques.


Assuntos
Aprendizado Profundo , Humanos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Imagens de Fantasmas , Processamento de Imagem Assistida por Computador
10.
Nat Cancer ; 3(11): 1300-1317, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36434392

RESUMO

Five-year survival for human papilloma virus-unrelated head and neck squamous cell carcinomas remain below 50%. We assessed the safety of administering combination hypofractionated stereotactic body radiation therapy with single-dose durvalumab (anti-PD-L1) neoadjuvantly (n = 21) ( NCT03635164 ). The primary endpoint of the study was safety, which was met. Secondary endpoints included radiographic, pathologic and objective response; locoregional control; progression-free survival; and overall survival. Among evaluable patients at an early median follow-up of 16 months (448 d or 64 weeks), overall survival was 80.1% with 95% confidence interval (95% CI) (62.0%, 100.0%), locoregional control and progression-free survival were 75.8% with 95% CI (57.5%, 99.8%), and major pathological response or complete response was 75% with 95% exact CI (51.6%, 100.0%). For patients treated with 24 Gy, 89% with 95% CI (57.1%, 100.0%) had MPR or CR. Using high-dimensional multi-omics and spatial data as well as biological correlatives, we show that responders had: (1) an increase in effector T cells; (2) a decrease in immunosuppressive cells; and (3) an increase in antigen presentation post-treatment.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Radiocirurgia , Humanos , Neoplasias de Cabeça e Pescoço/terapia , Terapia Neoadjuvante/efeitos adversos , Infecções por Papillomavirus/complicações , Radiocirurgia/efeitos adversos , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
11.
Pract Radiat Oncol ; 12(5): 370-386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35902341

RESUMO

PURPOSE: This guideline provides evidence-based recommendations for adults with isocitrate dehydrogenase (IDH)-mutant grade 2 and grade 3 diffuse glioma, as classified in the 2021 World Health Organization (WHO) Classification of Tumours. It includes indications for radiation therapy (RT), advanced RT techniques, and clinical management of adverse effects. METHODS: The American Society for Radiation Oncology convened a multidisciplinary task force to address 4 key questions focused on the RT management of patients with IDH-mutant grade 2 and grade 3 diffuse glioma. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength. RESULTS: A strong recommendation for close surveillance alone was made for patients with oligodendroglioma, IDH-mutant, 1p/19q codeleted, WHO grade 2 after gross total resection without high-risk features. For oligodendroglioma, WHO grade 2 with any high-risk features, adjuvant RT was conditionally recommended. However, adjuvant RT was strongly recommended for oligodendroglioma, WHO grade 3. A conditional recommendation for close surveillance alone was made for astrocytoma, IDH-mutant, WHO grade 2 after gross total resection without high-risk features. Adjuvant RT was conditionally recommended for astrocytoma, WHO grade 2, with any high-risk features and strongly recommended for astrocytoma, WHO grade 3. Dose recommendations varied based on histology and grade. Given known adverse long-term effects of RT, consideration for advanced techniques such as intensity modulated radiation therapy/volumetric modulated arc therapy or proton therapy were given as strong and conditional recommendations, respectively. Finally, based on expert opinion, the guideline recommends assessment, surveillance, and management for toxicity management. CONCLUSIONS: Based on published data, the American Society for Radiation Oncology task force has proposed recommendations to inform the management of adults with IDH-mutant grade 2 and grade 3 diffuse glioma as defined by WHO 2021 classification, based on the highest quality published data, and best translated by our task force of subject matter experts.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Linfoma Folicular , Oligodendroglioma , Adulto , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Glioma/genética , Glioma/radioterapia , Humanos , Organização Mundial da Saúde
12.
Adv Radiat Oncol ; 7(4): 100945, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814855

RESUMO

Purpose: : The role of peri-transplant radiation therapy (RT) in children with primary brain tumors is unclear. We characterized our institutional practice patterns and patient outcomes. Methods and Materials: The cohort included all patients treated with high-dose chemotherapy and autologous stem cell transplant for primary brain tumors at our institution from 2011 to 2017. Rates of local control, progression-free survival, overall survival, and radiation-associated injury were assessed. Results: Of the 37 eligible patients, 29 (78%) received peri-transplant RT. Patients treated with RT were more likely to have metastatic (P = .0121) and incompletely resected (P = .056) disease. Of those treated with RT, 13 (45%) received craniospinal irradiation (CSI) and 16 (55%) received focal RT. The median CSI dose was 23.4 Gy (interquartile range [IQR], 18-36 Gy; boost: median, 54 Gy [IQR, 53.7-55.8 Gy]) and focal RT dose was 50.4 Gy [IQR, 50.4-54.5 Gy]). Compared with the focal RT group, patients treated with CSI were older (P = .0499) and more likely to have metastatic disease (P = .0004). For the complete cohort, 2-year local control was 82% (95% confidence interval [CI], 70%-96%), progression-free survival 63% (95% CI, 49%-81%), and overall survival 65% (95% CI, 51%-82%). These rates did not differ significantly between patients treated with and without peri-transplant RT. Two cases of fatal myelopathy were observed after spinal cord doses within the highest tertile (41.4 cobalt Gy equivalent and 36 Gy). Conclusions: Peri-transplant RT was used for high-risk disease. Oncologic outcomes after RT were encouraging. However, 2 cases of grade 5 myelopathy were observed. If used cautiously, RT may contribute to durable remission in patients at high risk of relapse.

13.
Sci Immunol ; 7(72): eabl9330, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687697

RESUMO

Radiotherapy (RT) of colorectal cancer (CRC) can prime adaptive immunity against tumor-associated antigen (TAA)-expressing CRC cells systemically. However, abscopal tumor remissions are extremely rare, and the postirradiation immune escape mechanisms in CRC remain elusive. Here, we found that irradiated CRC cells used ATR-mediated DNA repair signaling pathway to up-regulate both CD47 and PD-L1, which through engagement of SIRPα and PD-1, respectively, prevented phagocytosis by antigen-presenting cells and thereby limited TAA cross-presentation and innate immune activation. This postirradiation CD47 and PD-L1 up-regulation was observed across various human solid tumor cells. Concordantly, rectal cancer patients with poor responses to neoadjuvant RT exhibited significantly elevated postirradiation CD47 levels. The combination of RT, anti-SIRPα, and anti-PD-1 reversed adaptive immune resistance and drove efficient TAA cross-presentation, resulting in robust TAA-specific CD8 T cell priming, functional activation of T effectors, and increased T cell clonality and clonal diversity. We observed significantly higher complete response rates to RT/anti-SIRPα/anti-PD-1 in both irradiated and abscopal tumors and prolonged survival in three distinct murine CRC models, including a cecal orthotopic model. The efficacy of triple combination therapy was STING dependent as knockout animals lost most benefit of adding anti-SIRPα and anti-PD-1 to RT. Despite activation across the myeloid stroma, the enhanced dendritic cell function accounts for most improvements in CD8 T cell priming. These data suggest ATR-mediated CD47 and PD-L1 up-regulation as a key mechanism restraining radiation-induced immune priming. RT combined with SIRPα and PD-1 blockade promotes robust antitumor immune priming, leading to systemic tumor regressions.


Assuntos
Antígeno CD47 , Neoplasias Colorretais , Animais , Antígenos de Neoplasias , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Antígeno B7-H1 , Antígeno CD47/metabolismo , Neoplasias Colorretais/radioterapia , Humanos , Camundongos , Receptor de Morte Celular Programada 1 , Regulação para Cima
14.
Nat Commun ; 12(1): 5531, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545084

RESUMO

Radiation-induced high-grade gliomas (RIGs) are an incurable late complication of cranial radiation therapy. We performed DNA methylation profiling, RNA-seq, and DNA sequencing on 32 RIG tumors and an in vitro drug screen in two RIG cell lines. We report that based on DNA methylation, RIGs cluster primarily with the pediatric receptor tyrosine kinase I high-grade glioma subtype. Common copy-number alterations include Chromosome (Ch.) 1p loss/1q gain, and Ch. 13q and Ch. 14q loss; focal alterations include PDGFRA and CDK4 gain and CDKN2A and BCOR loss. Transcriptomically, RIGs comprise a stem-like subgroup with lesser mutation burden and Ch. 1p loss and a pro-inflammatory subgroup with greater mutation burden and depleted DNA repair gene expression. Chromothripsis in several RIG samples is associated with extrachromosomal circular DNA-mediated amplification of PDGFRA and CDK4. Drug screening suggests microtubule inhibitors/stabilizers, DNA-damaging agents, MEK inhibition, and, in the inflammatory subgroup, proteasome inhibitors, as potentially effective therapies.


Assuntos
Glioma/genética , Glioma/patologia , Radiação , Adolescente , Criança , Estudos de Coortes , Simulação por Computador , Variações do Número de Cópias de DNA/genética , Metilação de DNA/genética , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Gradação de Tumores , Transcriptoma/genética , Adulto Jovem
15.
Oncoimmunology ; 9(1): 1846915, 2020 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-33344042

RESUMO

Immune checkpoint blockade (ICB) has demonstrated an impressive outcome in patients with metastatic melanoma, yet, durable complete response; even with Ipilimumab/Nivolumab combo are under 30%. Primary and acquired resistance in response to ICB is commonly due to a tumor immune escape mechanism dictated by the tumor microenvironment (TME). Macrophage Migratory Inhibition Factor (MIF) has emerged as an immunosuppressive factor secreted in the TME. We have previously demonstrated that blockade of the MIF-CD74 signaling on macrophages and dendritic cells restored the anti-tumor immune response against melanoma. Here, we report that inhibition of the MIF-CD74 axis combined with ipilimumab could render resistant melanoma to better respond to anti-CTLA-4 treatment. We provide evidence that blocking the MIF-CD74 signaling potentiates CD8+ T-cells infiltration and drives pro-inflammatory M1 conversion of macrophages in the TME. Furthermore, MIF inhibition resulted in reprogramming the metabolic pathway by reducing lactate production, HIF-1α and PD-L1 expression in the resistant melanoma cells. Melanoma patient data extracted from the TCGA database supports the hypothesis that high MIF expression strongly correlates with poor response to ICB therapy. Our findings provide a rationale for combining anti-CTLA-4 with MIF inhibitors as a potential strategy to overcome resistance to ICB therapy in melanoma, turning a "cold" tumor into a "hot" one mediated by the activation of innate immunity and reprogramming of tumor metabolism and reduced PD-L1 expression in melanoma cells.


Assuntos
Fatores Inibidores da Migração de Macrófagos , Melanoma , Humanos , Inibidores de Checkpoint Imunológico , Oxirredutases Intramoleculares/uso terapêutico , Ipilimumab/uso terapêutico , Fatores Inibidores da Migração de Macrófagos/uso terapêutico , Melanoma/tratamento farmacológico , Microambiente Tumoral
16.
Cancer Immunol Res ; 8(11): 1365-1380, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917656

RESUMO

Despite the clinical success of T-cell checkpoint blockade, most patients with cancer still fail to have durable responses to immunotherapy. The molecular mechanisms driving checkpoint blockade resistance, whether preexisting or evolved, remain unclear. To address this critical knowledge gap, we treated B16 melanoma with the combination of CTLA-4, PD-1, and PD-L1 blockade and a Flt3 ligand vaccine (≥75% curative), isolated tumors resistant to therapy, and serially passaged them in vivo with the same treatment regimen until they developed complete resistance. Using gene expression analysis and immunogenomics, we determined the adaptations associated with this resistance phenotype. Checkpoint resistance coincided with acquisition of a "hypermetabolic" phenotype characterized by coordinated upregulation of the glycolytic, oxidoreductase, and mitochondrial oxidative phosphorylation pathways. These resistant tumors flourished under hypoxic conditions, whereas metabolically starved T cells lost glycolytic potential, effector function, and the ability to expand in response to immunotherapy. Furthermore, we found that checkpoint-resistant versus -sensitive tumors could be separated by noninvasive MRI imaging based solely on their metabolic state. In a cohort of patients with melanoma resistant to both CTLA-4 and PD-1 blockade, we observed upregulation of pathways indicative of a similar hypermetabolic state. Together, these data indicated that melanoma can evade T-cell checkpoint blockade immunotherapy by adapting a hypermetabolic phenotype.


Assuntos
Imunoterapia/métodos , Melanoma Experimental/genética , Animais , Modelos Animais de Doenças , Humanos , Masculino , Melanoma Experimental/metabolismo , Camundongos , Fosforilação Oxidativa , Fenótipo
17.
BMC Fam Pract ; 21(1): 165, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32799797

RESUMO

BACKGROUND: As a large number of Community Health Service (CHS) centers in China face the majority of patients with non-valvular atrial fibrillation (NVAF), primary care physicians (PCPs) play a primary role in the prevention of embolization. Therefore, an awareness of anticoagulant management in patients with NVAF must be brought into focus among PCPs in China. This study investigated PCPs' knowledge, attitudes, and practices toward anticoagulant therapy in patients with NVAF, to help them understand their shortcomings regarding oral anticoagulant (OAC) therapy in preventing embolization. METHOD: This was a cross-sectional observational study of 462 PCPs in CHS centers across Shanghai. We used a self-administered questionnaire to collect data from September to December 2017. A stratified random cluster sampling was adopted in the 90 CHS centers with the family medicine residency program. RESULT: Among 462 participants, 69.3% (320/462) of females received a medical bachelor's degree and over 50% of participants had more than 10 years of work experience. Each section for knowledge, attitude, and practice were categorized as poor (≤39.0%), fair (40.0-69.0%), and good (≥70.0%). The level of knowledge of OAC therapy for patients with NVAF among PCPs was insufficient in over half (75.8%) of the participants. The majority (89.8%) of PCPs had a positive attitude and 68.0% had modest performance in the anticoagulant management of patients with NVAF. CONCLUSIONS: The knowledge and behaviors of PCPs were insufficient for OAC therapy to prevent embolization in patients with NVAF. The study also revealed that there is good potential for PCPs' educational interventions to positively impact the care of patients with NVAF.


Assuntos
Fibrilação Atrial , Médicos de Atenção Primária , Acidente Vascular Cerebral , Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , China , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Padrões de Prática Médica
18.
Am J Clin Oncol ; 43(8): 553-558, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32520791

RESUMO

AIM/OBJECTIVES/BACKGROUND: Timely, accurate, and effective communications are critical to quality in contemporary medical practices. Radiation oncology incorporates the science and technology of complex integrated radiation treatment delivery and the art of managing individual patients. Through written physical and/or electronic reports and direct communication, radiation oncologists convey critical information regarding patient care, services provided, and quality of care. Applicable practice parameters need to be revised periodically regarding medical record documentation for professional and technical components of services delivered. METHODS: The ACR-ASTRO Practice Parameter for Communication: Radiation Oncology was revised according to the process described on the American College of Radiology (ACR) Web site ("The Process for Developing ACR Practice Parameters and Technical Standards," www.acr.org/ClinicalResources/Practice-Parametersand-Technical-Standards) by the Committee on Practice Parameters of the ACR Commission on Radiation Oncology in collaboration with the American Society for Radiation Oncology (ASTRO). Both societies then reviewed and approved the document. RESULTS: This practice parameter addresses radiation oncology communications in general, including (a) medical record, (b) electronic, and (c) doctor-patient communications, as well as specific documentation for radiation oncology reports such as (a) consultation, (b) clinical treatment management notes (including inpatient communication), (c) treatment (completion) summary, and (d) follow-up visits. CONCLUSIONS: The radiation oncologist's participation in the multidisciplinary management of patients is reflected in timely, medically appropriate, and informative communication with the referring physician and other members of the health care team. The ACR-ASTRO Practice Parameter for Communication: Radiation Oncology is an educational tool designed to assist practitioners in providing appropriate communication regarding radiation oncology care for patients.


Assuntos
Comunicação , Relações Médico-Paciente , Radioterapia (Especialidade)/normas , Humanos , Prontuários Médicos
19.
Semin Cancer Biol ; 65: 155-163, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31982512

RESUMO

Advances in our understanding of tumor immune biology and development of cancer immunotherapies have led to improved outcomes for patients that suffer from aggressive cancers such as metastatic melanoma. Despite these advances, a significant proportion of patients still fail to benefit, and as a result, attention has shifted to understanding how cancer cells escape immune destruction. Of particular interest is the metabolic landscape of the tumor microenvironment, as recent studies have demonstrated how both competition for essential nutrients and depletion of specific amino acids can promote T cell dysfunction. Here, we will discuss the major energetic pathways engaged by both T cells and cancer cells, metabolic substrates present in the tumor microenvironment, and emerging therapeutic strategies that seek to improve T cell metabolic fitness and bolster the antitumor immune response.


Assuntos
Resistencia a Medicamentos Antineoplásicos/imunologia , Imunoterapia/efeitos adversos , Melanoma/terapia , Neoplasias/terapia , Humanos , Melanoma/imunologia , Doenças Mitocondriais , Metástase Neoplásica , Neoplasias/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
20.
Pediatr Blood Cancer ; 67(11): e28626, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33480469

RESUMO

BACKGROUND: Among pediatric hematopoietic stem cell transplant (HSCT) recipients, abnormal glycemic control is shown to be associated with increased risk of transplant-related mortality, death from any cause, risk of infection, increased hospitalized, and intensive care days. Independent effects of higher glycemic variability, a component of glycemic control, have not been described. This study aimed to characterize risk factors for, and consequences of, higher glycemic variability in HSCT patients. PROCEDURE: Medical records for a cohort of 344 patients, age 0-30 years, who underwent first HSCT from 2007 to 2016 at Children's Hospital Colorado were retrospectively reviewed. Glucose coefficients of variation (CV) were analyzed for HSCT days -14 to 0 and 0-30, and patients were assessed for potential risk factors and outcomes. RESULTS: Roughly one-third of patients had pre-HSCT and day 0-30 glucose CV above the reported healthy adult range. Independent of HSCT type, doubling of pre-HSCT glucose CV was associated with a 4.91-fold (95% confidence interval [CI], 1.40-17.24) increased hazard of infection, as well as increased risk for intensive care hospitalization for allogenic HSCT patients. Multivariable analysis demonstrated that allogeneic HSCT patients had a 1.40- and 1.38-fold (95% CI, 0.98-1.99 and 1.00-1.91) increased hazard of death for every doubling of pre-HSCT and day 0-30 glucose CV, respectively. CONCLUSIONS: Just as with higher mean glucose, higher glycemic variability in the pediatric HSCT population is independently associated with significantly increased morbidity. Additional research is required to evaluate the utility of glucose control to mitigate these relationships and improve HSCT outcomes.


Assuntos
Glicemia/análise , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hiperglicemia/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Hiperglicemia/sangue , Lactente , Masculino , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
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