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1.
Lancet Oncol ; 23(9): 1189-1200, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35952709

RESUMO

BACKGROUND: TGF-ß is an immunosuppressive cytokine that is upregulated in colorectal cancer. TGF-ß blockade improved response to chemoradiotherapy in preclinical models of colorectal adenocarcinoma. We aimed to test the hypothesis that adding the TGF-ß type I receptor kinase inhibitor galunisertib to neoadjuvant chemoradiotherapy would improve pathological complete response rates in patients with locally advanced rectal cancer. METHODS: This was an investigator-initiated, single-arm, phase 2 study done in two medical centres in Portland (OR, USA). Eligible patients had previously untreated, locally advanced, rectal adenocarcinoma, stage IIA-IIIC or IV as per the American Joint Committee on Cancer; Eastern Cooperative Oncology Group status 0-2; and were aged 18 years or older. Participants completed two 14-day courses of oral galunisertib 150 mg twice daily, before and during fluorouracil-based chemoradiotherapy (intravenous fluorouracil 225 mg/m2 over 24 h daily 7 days per week during radiotherapy or oral capecitabine 825 mg/m2 twice per day 5 days per week during radiotherapy; radiotherapy consisted of 50·4-54·0 Gy in 28-30 fractions). 5-9 weeks later, patients underwent response assessment. Patients with a complete response could opt for non-operative management and proceed to modified FOLFOX6 (intravenous leucovorin 400 mg/m2 on day 1, intravenous fluorouracil 400 mg/m2 on day 1 then 2400 mg/m2 over 46 h, and intravenous oxaliplatin 85 mg/m2 on day 1 delivered every 2 weeks for eight cycles) or CAPEOX (intravenous oxaliplatin 130 mg/m2 on day 1 and oral capecitabine 1000 mg/m2 twice daily for 14 days every 3 weeks for four cycles). Patients with less than complete response underwent surgical resection. The primary endpoint was complete response rate, which was a composite of pathological complete response in patients who proceeded to surgery, or clinical complete response maintained at 1 year after last therapy in patients with non-operative management. Safety was a coprimary endpoint. Both endpoints were assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT02688712, and is active but not recruiting. FINDINGS: Between Oct 19, 2016, and Aug 31, 2020, 38 participants were enrolled. 25 (71%) of the 35 patients who completed chemoradiotherapy proceeded to total mesorectal excision surgery, five (20%) of whom had pathological complete responses. Ten (29%) patients had non-operative management, three (30%) of whom ultimately chose to have total mesorectal excision. Two (67%) of those three patients had pathological complete responses. Of the remaining seven patients in the non-operative management group, five (71%) had clinical complete responses at 1 year after their last modified FOLFOX6 infusion. In total, 12 (32% [one-sided 95% CI ≥19%]) of 38 patients had a complete response. Common grade 3 adverse events during treatment included diarrhoea in six (16%) of 38 patients, and haematological toxicity in seven (18%) patients. Two (5%) patients had grade 4 adverse events, one related to chemoradiotherapy-induced diarrhoea and dehydration, and the other an intraoperative ischaemic event. No treatment-related deaths occurred. INTERPRETATION: The addition of galunisertib to neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer improved the complete response rate to 32%, was well tolerated, and warrants further assessment in randomised trials. FUNDING: Eli Lilly via ExIST program, The Providence Foundation.


Assuntos
Adenocarcinoma , Segunda Neoplasia Primária , Neoplasias Retais , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Quimiorradioterapia/efeitos adversos , Diarreia/etiologia , Fluoruracila , Humanos , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Segunda Neoplasia Primária/patologia , Oxaliplatina , Pirazóis , Quinolinas , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/patologia , Fator de Crescimento Transformador beta
2.
Mol Carcinog ; 61(2): 165-172, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34644811

RESUMO

Radiation has been utilized as a direct cytotoxic tumorcidal modality, however, the effect of radiation on tumor vasculature influences response to anticancer therapies. Although numerous reports have demonstrated vascular changes in irradiated tumors, the findings and implications are extensive and at times contradictory depending on the radiation dose, timing, and models used. In this review, we focus on the radiation-mediated effects on tumor vasculature with respect to doses used, timing postradiation, vasculogenesis, adhesion molecule expression, permeability, and pericyte coverage, including the latest findings.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Neovascularização Patológica/tratamento farmacológico
3.
New Phytol ; 236(1): 15-20, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35706381

RESUMO

Drylands, which cover > 40% of Earth's terrestrial surface, are dominant drivers of global biogeochemical cycling and home to more than one third of the global human population. Climate projections predict warming, drought frequency and severity, and evaporative demand will increase in drylands at faster rates than global means. As a consequence of extreme temperatures and high biological dependency on limited water availability, drylands are predicted to be exceptionally sensitive to climate change and, indeed, significant climate impacts are already being observed. However, our understanding and ability to forecast climate change effects on dryland biogeochemistry and ecosystem functions lag behind many mesic systems. To improve our capacity to forecast ecosystem change, we propose focusing on the controls and consequences of two key characteristics affecting dryland biogeochemistry: (1) high spatial and temporal heterogeneity in environmental conditions and (2) generalized resource scarcity. In addition to climate change, drylands are experiencing accelerating land-use change. Building our understanding of dryland biogeochemistry in both intact and disturbed systems will better equip us to address the interacting effects of climate change and landscape degradation. Responding to these challenges will require a diverse, globally distributed and interdisciplinary community of dryland experts united towards better understanding these vast and important ecosystems.


Assuntos
Mudança Climática , Ecossistema , Secas , Humanos , Solo , Água
4.
Bioscience ; 71(9): 907-917, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34483747

RESUMO

Dryland degradation is a persistent and accelerating global problem. Although the mechanisms initiating and maintaining dryland degradation are largely understood, returning productivity and function through ecological restoration remains difficult. Water limitation commonly drives slow recovery rates within drylands; however, the altered biogeochemical cycles that accompany degradation also play key roles in limiting restoration outcomes. Addressing biogeochemical changes and resource limitations may help improve restoration efforts within this difficult-to-restore biome. In the present article, we present a synthesis of restoration literature that identifies multiple ways biogeochemical understandings might augment dryland restoration outcomes, including timing restoration around resource cycling and uptake, connecting heterogeneous landscapes, manipulating resource pools, and using organismal functional traits to a restoration advantage. We conclude by suggesting ways to incorporate biogeochemistry into existing restoration frameworks and discuss research directions that may help improve restoration outcomes in the world's highly altered dryland landscapes.

5.
Ecol Appl ; 29(5): e01908, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31004536

RESUMO

Land degradation is a persistent ecological problem in many arid and semiarid systems globally (drylands hereafter). Most instances of dryland degradation include some form of soil disturbance and/or soil erosion, which can hinder vegetation establishment and reduce ecosystem productivity. To combat soil erosion, researchers have identified a need for rehabilitation of biological soil crusts (biocrusts), a globally relevant community of organisms aggregating the soil surface and building soil fertility. Here, the impact of plant and biocrust cover was tested on soil erosion potential in the piñon-juniper woodlands of Bandelier National Monument, New Mexico, USA. Biocrusts were found to be similarly influential to vascular plants in reducing erosion, largely acting by promoting surface roughness. The potential to rehabilitate biocrusts within the Monument was also tested. Plots were inoculated on eroding soils before the summer monsoon with greenhouse-cultured biocrusts. In a full-factorial design, treatments to reduce or halt erosion were administered to the inoculated plots and their paired controls. These erosion-reduction treatments included barriers to overland flow (flashing), slash placement, and seeding of vascular plants. Dynamic changes to soil stability, penetration resistance, and extractable soil nutrients were observed through time, but no strong effects with the addition of biocrust inoculum, seeding, or erosion intervention treatments were seen. The results do suggest possible ways forward to successfully rehabilitate biocrust, including varying the timing of biocrust application, amending inoculum application with different types of soil stabilization techniques, and adding nutrients to soils. The insights gleaned from the lack of response brings us closer to developing effective techniques to arrest soil loss in these socially and ecologically important dryland systems.


Assuntos
Ecossistema , Solo , New Mexico , Microbiologia do Solo
7.
Hepatol Res ; 47(7): 702-714, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27501850

RESUMO

AIM: Small, solitary hepatocellular carcinoma is curable with stereotactic radiation or other methods of tumor ablation, however, regional and systemic tumor recurrence occurs in over 70% of patients. Here we describe the ability of immunoradiotherapy to induce an antitumor immune response and delay the growth of tumors in immunocompetent mice. METHODS: A syngeneic hepatocellular carcinoma cell line (Hep-55.1c) was injected directly into the livers of C57BL/6 mice using ultrasound guidance, then tumors were treated with stereotactic radiation using a Small Animal Radiation Research Platform with computed tomography guidance. RESULTS: Delivery of three doses of 250 µg anti-programmed cell death protein-1 (αPD-1) antibody concurrently with 30 Gy stereotactic body radiation therapy in three fractions reduced the growth rate of tumors and improved survival (P < 0.05). Combined treatment was associated with increased CD8+ cytotoxic T cells in the tumor; depletion of CD8 T cells eliminated the efficacy of combined treatment. Combined treatment also induced expression of programmed cell death-1 ligand expression on tumor-infiltrating macrophages, and the tumors grew rapidly after αPD-1 treatment was discontinued. CONCLUSIONS: Tumor response to stereotactic radiation can be augmented by concurrent treatment with αPD-1. The efficacy of this combination therapy was transient, however, and treatment induced markers of adaptive immune resistance. These data are promising, but also indicate that mechanisms of immune resistance will need to be durably overcome for this combination to generate lasting immunity to protect against tumor recurrence.

9.
Clin Dev Immunol ; 2013: 281958, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23653658

RESUMO

Radiation therapy is showing potential as a partner for immunotherapies in preclinical cancer models and early clinical studies. As has been discussed elsewhere, radiation provides debulking, antigen and adjuvant release, and inflammatory targeting of effector cells to the treatment site, thereby assisting multiple critical checkpoints in antitumor adaptive immunity. Adaptive immunity is terminated by inflammatory resolution, an active process which ensures that inflammatory damage is repaired and tissue function is restored. We discuss how radiation therapy similarly triggers inflammation followed by repair, the consequences to adaptive immune responses in the treatment site, and how the myeloid response to radiation may impact immunotherapies designed to improve control of residual cancer cells.


Assuntos
Inflamação/radioterapia , Células Mieloides/efeitos da radiação , Neoplasias/radioterapia , Imunidade Adaptativa/efeitos da radiação , Animais , Antígenos de Neoplasias/imunologia , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Imunomodulação , Imunoterapia , Células Mieloides/imunologia , Neoplasias/imunologia , Cicatrização/efeitos da radiação
10.
Sci Rep ; 13(1): 6277, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072485

RESUMO

Tissue resident memory (Trm) CD8 T cells infiltrating tumors represent an enriched population of tumor antigen-specific T cells, and their presence is associated with improved outcomes in patients. Using genetically engineered mouse pancreatic tumor models we demonstrate that tumor implantation generates a Trm niche that is dependent on direct antigen presentation by cancer cells. However, we observe that initial CCR7-mediated localization of CD8 T cells to tumor draining lymph nodes is required to subsequently generate CD103+ CD8 T cells in tumors. We observe that the formation of CD103+ CD8 T cells in tumors is dependent on CD40L but independent of CD4 T cells, and using mixed chimeras we show that CD8 T cells can provide their own CD40L to permit CD103+ CD8 T cell differentiation. Finally, we show that CD40L is required to provide systemic protection against secondary tumors. These data suggest that CD103+ CD8 T cell formation in tumors can occur independent of the two-factor authentication provided by CD4 T cells and highlight CD103+ CD8 T cells as a distinct differentiation decision from CD4-dependent central memory.


Assuntos
Memória Imunológica , Neoplasias , Animais , Camundongos , Ligante de CD40 , Neoplasias/patologia , Linfócitos T CD8-Positivos , Ativação Linfocitária
11.
Kidney Int ; 82(8): 857-66, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22495293

RESUMO

Arteriolar hyalinosis is a common histological finding in renal transplant recipients treated with the calcineurin inhibitor tacrolimus; however, the pathophysiologic mechanisms remain unknown. In addition to increasing transforming growth factor (TGF)-ß levels, tacrolimus inhibits calcineurin by binding to FK506-binding protein 12 (FKBP12). FKBP12 alone also inhibits TGF-ß receptor activation. Here we tested whether tacrolimus binding to FKBP12 removes an inhibition of the TGF-ß receptor, allowing ligand binding, ultimately leading to receptor activation and arteriolar hyalinosis. We found that specific deletion of FKBP12 from endothelial cells was sufficient to activate endothelial TGF-ß receptors and induce renal arteriolar hyalinosis in these knockout mice, similar to that induced by tacrolimus. Tacrolimus-treated and knockout mice exhibited significantly increased levels of aortic TGF-ß receptor activation as evidenced by SMAD2/3 phosphorylation, along with increased collagen and fibronectin expression compared to controls. Treatment of isolated mouse aortas with tacrolimus increased TGF-ß receptor activation and collagen and fibronectin expression. These effects were independent of calcineurin, absent in endothelial denuded aortic rings, and could be prevented by the small molecule TGF-ß receptor inhibitor SB-505124. Thus, endothelial cell TGF-ß receptor activation is sufficient to cause vascular remodeling and renal arteriolar hyalinosis.


Assuntos
Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Tacrolimo/toxicidade , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/metabolismo , Arteríolas/patologia , Benzodioxóis/farmacologia , Inibidores de Calcineurina , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Hialina/metabolismo , Imidazóis/farmacologia , Imunossupressores/metabolismo , Imunossupressores/toxicidade , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Piridinas/farmacologia , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Proteínas Smad/metabolismo , Tacrolimo/metabolismo , Proteína 1A de Ligação a Tacrolimo/deficiência , Proteína 1A de Ligação a Tacrolimo/genética , Proteína 1A de Ligação a Tacrolimo/metabolismo
12.
J Clin Invest ; 132(18)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36106641

RESUMO

Patients with HPV-unrelated head and neck squamous cell carcinoma (HPV-unrelated HNSCC) show only modest benefit from treatment with PD-1 inhibitors (PD-1i). Targeting transforming growth factor ß (TGF-ß) may make PD-1i more effective by inducing T cell responses. In this issue of the JCI, Redman et al. performed a clinical trial in 14 patients with HPV-unrelated HNSCC using bintrafusp alfa, a bifunctional fusion protein that blocks PD-L1 and TGF-ß. Primary tumors displayed pathologic responses with 5 of 14 patients having at least a partial response. While no primary tumor or metastatic lymph node demonstrated a complete pathologic response, the findings suggest that concurrent neoadjuvant inhibition of PD-L1 and TGF-ß may provide a rational strategy to improve pathologic response and clinical outcome in patients with HPV-unrelated HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Antígeno B7-H1/metabolismo , Ensaios Clínicos como Assunto , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Inibidores de Checkpoint Imunológico , Fatores Imunológicos , Imunoterapia , Terapia Neoadjuvante , Infecções por Papillomavirus/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Sinapses/metabolismo , Linfócitos T/metabolismo , Fator de Crescimento Transformador beta
13.
Cancer Biol Ther ; 23(1): 1-8, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36201632

RESUMO

Stereotactic body radiotherapy (SBRT) demonstrates excellent local control in early stage lung cancer, however a quarter of patients develop recurrence or distant metastasis. Transforming growth factor-beta (TGF-ß) supports metastasis and treatment resistance, and angiotensin receptor blockade (ARB) indirectly suppresses TGF-ß signaling. This study investigates whether patients taking ARBs while undergoing SBRT for early stage lung cancer exhibited improved overall survival (OS) or recurrence free survival (RFS) compared to patients not taking ARBs. This was a single institution retrospective analysis of 272 patients treated with SBRT for early stage lung cancer between 2009 and 2018. Patient health data was abstracted from the electronic medical record. OS and RFS were assessed using Kaplan-Meier method. Log-rank test was used to compare unadjusted survival between groups. Univariable and multivariable Cox proportional hazard regression models were used to estimate hazard ratios (HRs). Of 247 patients analyzed, 24 (10%) patients took ARBs for the duration of radiotherapy. There was no difference in mean age, median tumor diameter, or median biologic effective dose between patients taking ARBs or not. Patients taking ARBs exhibited increased OS (ARB = 96.7 mo.; no ARB = 43.3 mo.; HR = 0.25 [95% CI: 0.10 to 0.62, P = .003]) and increased RFS (median RFS, ARB = 64.3 mo.; No ARB = 35.1 mo.; HR = 0.26 [95% CI: 0.10 to 0.63, P = .003]). These effects were not seen in patients taking angiotensin converting enzyme inhibitors (ACEIs) or statins. ARB use while undergoing SBRT for early stage lung cancer may increase OS and RFS, but ACEI use does not show the same effect.


Assuntos
Produtos Biológicos , Carcinoma Pulmonar de Células não Pequenas , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Pulmonares , Radiocirurgia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Produtos Biológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Receptores de Angiotensina/uso terapêutico , Estudos Retrospectivos , Fator de Crescimento Transformador beta , Fatores de Crescimento Transformadores/uso terapêutico , Resultado do Tratamento
14.
Biol Rev Camb Philos Soc ; 97(5): 1768-1785, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35584903

RESUMO

Studies of biological soil crusts (biocrusts) have proliferated over the last few decades. The biocrust literature has broadened, with more studies assessing and describing the function of a variety of biocrust communities in a broad range of biomes and habitats and across a large spectrum of disciplines, and also by the incorporation of biocrusts into global perspectives and biogeochemical models. As the number of biocrust researchers increases, along with the scope of soil communities defined as 'biocrust', it is worth asking whether we all share a clear, universal, and fully articulated definition of what constitutes a biocrust. In this review, we synthesize the literature with the views of new and experienced biocrust researchers, to provide a refined and fully elaborated definition of biocrusts. In doing so, we illustrate the ecological relevance and ecosystem services provided by them. We demonstrate that biocrusts are defined by four distinct elements: physical structure, functional characteristics, habitat, and taxonomic composition. We describe outgroups, which have some, but not all, of the characteristics necessary to be fully consistent with our definition and thus would not be considered biocrusts. We also summarize the wide variety of different types of communities that fall under our definition of biocrusts, in the process of highlighting their global distribution. Finally, we suggest the universal use of the Belnap, Büdel & Lange definition, with minor modifications: Biological soil crusts (biocrusts) result from an intimate association between soil particles and differing proportions of photoautotrophic (e.g. cyanobacteria, algae, lichens, bryophytes) and heterotrophic (e.g. bacteria, fungi, archaea) organisms, which live within, or immediately on top of, the uppermost millimetres of soil. Soil particles are aggregated through the presence and activity of these often extremotolerant biota that desiccate regularly, and the resultant living crust covers the surface of the ground as a coherent layer. With this detailed definition of biocrusts, illustrating their ecological functions and widespread distribution, we hope to stimulate interest in biocrust research and inform various stakeholders (e.g. land managers, land users) on their overall importance to ecosystem and Earth system functioning.


Assuntos
Briófitas , Cianobactérias , Ecossistema , Solo/química , Microbiologia do Solo
15.
J Pharmacol Exp Ther ; 337(3): 718-23, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21383022

RESUMO

FK506 [tacrolimus; hexadecahydro-5,19-dihydroxy-3-[2-(4-hydroxy-3-methoxycyclohexyl)-1-methylethenyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-8-(2-propenyl)-15,19-epoxy-3H-pyrido[2,1-c][1,4]oxa-azacyclotricosine-1,7,20,21(4H,23H)-tetrone] is used clinically to reduce the incidence of allograft rejection; however, chronic administration leads to endothelial dysfunction and hypertension. We have previously shown that FK506 activates Ca(2+)/diacylglycerol-dependent conventional protein kinase C (cPKC), which phosphorylates endothelial nitric oxide synthase (eNOS) at one of its inhibitory sites, Thr495. However, which cPKC isoform is responsible for phosphorylating eNOS Thr495 is unknown. The aim of the current study was to determine the cPKC isoform that is activated by FK506, leading to decreased endothelial function. FK506 reduced endothelium-dependent relaxation responses, yet had no effect on endothelium-independent relaxation responses in aortas from control mice. Of the various cPKC isoforms, only the administration of a PKCß(II) isoform-specific peptide inhibitor restored aortic relaxation responses to that of controls. In aortic endothelial cells, FK506 significantly increased PKCß(II) activation compared with vehicle-treated controls, and this was prevented by a PKCß(II) isoform-specific peptide inhibitor. In addition, a PKCß(II) isoform-specific peptide inhibitor prevented the increase in eNOS Thr495 phosphorylation induced by FK506. Taken together, our results indicate that ß(II) is the cPKC isoform responsible for phosphorylating eNOS at the inhibitory site Thr495 in response to FK506. PKCß(II) inhibition could prove beneficial in ameliorating the endothelial dysfunction and hypertension in patients treated with FK506.


Assuntos
Aorta/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Imunossupressores/toxicidade , Óxido Nítrico Sintase Tipo III/metabolismo , Proteína Quinase C/metabolismo , Tacrolimo/toxicidade , Treonina/metabolismo , Animais , Células Cultivadas , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C beta , Ratos , Tacrolimo/metabolismo , Tacrolimo/farmacologia , Doenças Vasculares/tratamento farmacológico
16.
New Phytol ; 210(1): 18-22, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26919695

Assuntos
Clima , Ecossistema , Solo
17.
Oncoimmunology ; 10(1): 1900635, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33796412

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has traditionally been thought of as an immunologically quiescent tumor type presumably because of a relatively low tumor mutational burden (TMB) and poor responses to checkpoint blockade therapy. However, many PDAC tumors exhibit T cell inflamed phenotypes. The presence of tertiary lymphoid structures (TLS) has recently been shown to be predictive of checkpoint blockade response in melanomas and sarcomas, and are prognostic for survival in PDAC. In order to more comprehensively understand tumor immunity in PDAC patients with TLS, we performed RNA-seq, single and multiplex IHC, flow cytometry and predictive genomic analysis on treatment naïve, PDAC surgical specimens. Forty-six percent of tumors contained distinct T and B cell aggregates reflective of "early-stage TLS" (ES-TLS), which correlated with longer overall and progression-free survival. These tumors had greater CD8+ T cell infiltration but were not defined by previously published TLS gene-expression signatures. ES-TLS+ tumors were enriched for IgG1 class-switched memory B cells and memory CD4+ T cells, suggesting durable immunological memory persisted in these patients. We also observed the presence of active germinal centers (mature-TLS) in 31% of tumors with lymphocyte clusters, whose patients had long-term survival (median 56 months). M-TLS-positive tumors had equivalent overall T cell infiltration to ES-TLS, but were enriched for activated CD4+ memory cells, naive B cells and NK cells. Finally, using a TCGA-PDAC dataset, ES-TLS+ tumors harbored a decreased TMB, but M-TLS with germinal centers expressed significantly more MHCI-restricted neoantigens as determined by an in silico neoantigen prediction method. Interestingly, M-TLS+ tumors also had evidence of increased rates of B cell somatic hypermutation, suggesting that germinal centers form in the presence of high-quality tumor neoantigens leading to increased humoral immunity that confers improved survival for PDAC patients. AbbreviationsTLS: tertiary lymphoid structures; GC: germinal center(s); PDAC: pancreatic ductal adenocarcinoma; RNA-seq: RNA sequencing; BCRseq: B cell receptor sequencing; HEV: high endothelial venule; PNAd: peripheral node addressin; TMB: tumor mutational burden; TCGA: the cancer genome atlas; PAAD: pancreatic adenocarcinoma; FFPE: formalin fixed paraffin embedded; TIME: tumor immune microenvironment.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Estruturas Linfoides Terciárias , Centro Germinativo , Humanos , Imunidade Humoral , Neoplasias Pancreáticas/genética , Sobrevivência , Microambiente Tumoral
18.
J Immunother Cancer ; 9(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33963014

RESUMO

BACKGROUND: Checkpoint inhibitors targeting programmed death receptor-1 (PD-1) have been tested in the neoadjuvant setting for the treatment of locoregionally advanced head and neck squamous cell carcinoma (HNSCC); however, response rates are modest. We hypothesized that adding stereotactic body radiation therapy (SBRT) to anti-PD-1 would be safe prior to definitive surgical resection and would enhance pathological response compared with historical cohorts of patients with locoregionally advanced HNSCC treated with checkpoint inhibitor alone. METHODS: The Neoadjuvant Immuno-Radiotherapy Trial was an investigator-initiated single institution phase Ib clinical trial that enrolled patients with previously untreated locally advanced HPV-positive and HPV-negative HNSCC between 2018 and 2019. Eligible patients were treated with neoadjuvant SBRT at a total dose of either 40 Gy in 5 fractions or 24 Gy in 3 fractions, delivered in a 1-week timespan, with or without nivolumab, prior to definitive surgical resection. Patients were then planned for treatment with adjuvant nivolumab for 3 months. The primary safety endpoint was unplanned delay in surgery considered to be at least possibly related to neoadjuvant treatment. The primary efficacy endpoints included pathological complete response (pCR), major pathological response (mPR), and the rate of clinical to pathological downstaging after neoadjuvant treatment. RESULTS: Twenty-one patients underwent neoadjuvant treatment, which was well tolerated and did not delay surgery, thus meeting the primary endpoint. Tissue responses were characterized by robust inflammatory infiltrates in the regression bed, plasma cells and cholesterol clefts. Among the entire study group, the mPR and pCR rate was 86% and 67%, respectively. Clinical to pathological downstaging occurred in 90% of the patients treated. CONCLUSION: These data demonstrate that radiation delivered only to the gross tumor volume combined with immunotherapy was safe, resulted in a high rate of mPR and should be further evaluated as a locally focused neoadjuvant therapy for patients with head and neck cancer. TRIAL REGISTRATION NUMBER: This study is registered with clinicaltrials.gov (NCT03247712) and is active, but closed to patient accrual.


Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia , Terapia Neoadjuvante , Nivolumabe/uso terapêutico , Radiocirurgia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Idoso , Fracionamento da Dose de Radiação , Feminino , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Imunoterapia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Estadiamento de Neoplasias , Nivolumabe/efeitos adversos , Oregon , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Radiocirurgia/efeitos adversos , Radioterapia Adjuvante , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fatores de Tempo , Resultado do Tratamento
19.
Semin Radiat Oncol ; 30(2): 158-172, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32381295

RESUMO

Immunotherapies are rapidly entering the clinic as approved treatments for diverse cancer pathologies. Radiation therapy is an integral partner in cancer therapy, commonly as part of complicated multimodality approaches that optimize patient outcomes. Preclinical studies have demonstrated that the success of radiation therapy in tumor control is due in part to immune mechanisms, and that outcomes following radiation therapy can be improved through combination with a range of immunotherapies. However, preclinical models of cancer are very different from patient tumors, and the way these preclinical tumors are treated is often very different from standard of care treatment of patients. This review examines the preclinical and clinical data for the role of the immune system in radiation therapy outcomes, and how to integrate preclinical findings into clinical trials, using ongoing studies as examples.


Assuntos
Ensaios Clínicos como Assunto , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/radioterapia , Projetos de Pesquisa , Animais , Terapia Combinada , Modelos Animais de Doenças , Humanos
20.
Semin Radiat Oncol ; 30(2): 145-157, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32381294

RESUMO

A malignant tumor consists of malignant cells as well as a wide array of normal host tissues including stroma, vasculature, and immune infiltrate. The interaction between cancer and these host tissues is critical as these host tissues play a variety of roles in supporting or resisting disease progression. Radiotherapy (RT) has direct effects on malignant cells, but, also, critically important effects on these other components of the tumor microenvironment (TME). Given the growing role of immune checkpoint inhibitors and other immunotherapy strategies, understanding how RT affects the TME, particularly the immune compartment, is essential to advance RT in this new era of cancer therapy. The interactions between RT and the TME are complex, affecting the innate and adaptive arms of the immune system. RT can induce both proinflammatory effects and immune suppressive effects that can either promote or impede antitumor immunity. It is likely that the initial proinflammatory effects of RT eventually lead to rebound immune-suppression as chronic inflammation sets in. The exact kinetics and nature of how RT changes the TME likely depends on timing, dose, fractionation, site irradiated, and tumor type. With increased understanding of the effects of RT on the TME, in the future it is likely that we will be able to personalize RT by varying the dose, site, and timing of intervention to generate the desired response to partner with immunotherapy strategies.


Assuntos
Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/radioterapia , Microambiente Tumoral/imunologia , Microambiente Tumoral/efeitos da radiação , Imunidade Adaptativa/efeitos da radiação , Humanos , Imunidade Inata/efeitos da radiação
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