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1.
J Immunol ; 212(7): 1129-1141, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363226

RESUMO

In contrast to the "helper" activities of most CD4+ T effector subsets, CD4+ cytotoxic T lymphocytes (CD4-CTLs) perform functions normally associated with CD8+ T and NK cells. Specifically, CD4-CTLs secrete cytotoxic molecules and directly target and kill compromised cells in an MHC class II-restricted fashion. The functions of these cells have been described in diverse immunological contexts, including their ability to provide protection during antiviral and antitumor responses, as well as being implicated in autoimmunity. Despite their significance to human health, the complete mechanisms that govern their programming remain unclear. In this article, we identify the Ikaros zinc finger transcription factor Eos (Ikzf4) as a positive regulator of CD4-CTL differentiation during murine immune responses against influenza virus infection. We find that the frequency of Eos+ cells is elevated in lung CD4-CTL populations and that the cytotoxic gene program is compromised in Eos-deficient CD4+ T cells. Consequently, we observe a reduced frequency and number of lung-residing, influenza virus-responsive CD4-CTLs in the absence of Eos. Mechanistically, we determine that this is due, at least in part, to reduced expression of IL-2 and IL-15 cytokine receptor subunits on the surface of Eos-deficient CD4+ T cells, both of which support the CD4-CTL program. Finally, we find that Aiolos, a related Ikaros family member and known CD4-CTL antagonist, represses Eos expression by antagonizing STAT5-dependent activation of the Ikzf4 promoter. Collectively, our findings reveal a mechanism wherein Eos and Aiolos act in opposition to regulate cytotoxic programming of CD4+ T cells.


Assuntos
Antineoplásicos , Linfócitos T CD4-Positivos , Camundongos , Humanos , Animais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Linfócitos T Citotóxicos , Diferenciação Celular , Citocinas/metabolismo , Antineoplásicos/metabolismo
2.
J Immunol ; 211(3): 365-376, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37314436

RESUMO

The Ikaros zinc-finger transcription factor Eos has largely been associated with sustaining the immunosuppressive functions of regulatory T cells. Paradoxically, Eos has more recently been implicated in promoting proinflammatory responses in the dysregulated setting of autoimmunity. However, the precise role of Eos in regulating the differentiation and function of effector CD4+ T cell subsets remains unclear. In this study, we find that Eos is a positive regulator of the differentiation of murine CD4+ TH2 cells, an effector population that has been implicated in both immunity against helminthic parasites and the induction of allergic asthma. Using murine in vitro TH2 polarization and an in vivo house dust mite asthma model, we find that EosKO T cells exhibit reduced expression of key TH2 transcription factors, effector cytokines, and cytokine receptors. Mechanistically, we find that the IL-2/STAT5 axis and its downstream TH2 gene targets are one of the most significantly downregulated pathways in Eos-deficient cells. Consistent with these observations, we find that Eos forms, to our knowledge, a novel complex with and supports the tyrosine phosphorylation of STAT5. Collectively, these data define a regulatory mechanism whereby Eos propagates STAT5 activity to facilitate TH2 cell differentiation.


Assuntos
Asma , Fator de Transcrição STAT5 , Camundongos , Animais , Fator de Transcrição STAT5/metabolismo , Diferenciação Celular , Citocinas/metabolismo , Células Th2
3.
J Immunol ; 207(12): 3107-3121, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34810223

RESUMO

Hepatocyte transplant represents a treatment for metabolic disorders but is limited by immunogenicity. Our prior work identified the critical role of CD8+ T cells, with or without CD4+ T cell help, in mediating hepatocyte rejection. In this study, we evaluated the influence of invariant NKT (iNKT) cells, uniquely abundant in the liver, upon CD8-mediated immune responses in the presence and absence of CD4+ T cells. To investigate this, C57BL/6 (wild-type) and iNKT-deficient Jα18 knockout mice (cohorts CD4 depleted) were transplanted with allogeneic hepatocytes. Recipients were evaluated for alloprimed CD8+ T cell subset composition, allocytotoxicity, and hepatocyte rejection. We found that CD8-mediated allocytotoxicity was significantly decreased in iNKT-deficient recipients and was restored by adoptive transfer of iNKT cells. In the absence of both iNKT cells and CD4+ T cells, CD8-mediated allocytotoxicity and hepatocyte rejection was abrogated. iNKT cells enhance the proportion of a novel subset of multipotent, alloprimed CXCR3+CCR4+CD8+ cytolytic T cells that develop after hepatocyte transplant and are abundant in the liver. Alloprimed CXCR3+CCR4+CD8+ T cells express cytotoxic effector molecules (perforin/granzyme and Fas ligand) and are distinguished from alloprimed CXCR3+CCR4-CD8+ T cells by a higher proportion of cells expressing TNF-α and IFN-γ. Furthermore, alloprimed CXCR3+CCR4+CD8+ T cells mediate higher allocytotoxicity and more rapid allograft rejection. Our data demonstrate the important role of iNKT cells in promoting the development of highly cytotoxic, multipotent CXCR3+CCR4+CD8+ T cells that mediate rapid rejection of allogeneic hepatocytes engrafted in the liver. Targeting iNKT cells may be an efficacious therapy to prevent rejection of intrahepatic cellular transplants.


Assuntos
Transplante de Fígado , Células T Matadoras Naturais , Aloenxertos , Animais , Linfócitos T CD8-Positivos , Rejeição de Enxerto , Hepatócitos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
4.
J Cell Mol Med ; 26(16): 4591-4601, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35841281

RESUMO

Tumour Necrosis Factor (TNF) potently induces a transient inflammatory response that must be downregulated once any invasive stimulus has resolved. Yet, how TNF-induced inflammation is shut down in normal cells is incompletely understood. The present study shows that STAT3 was activated in mouse embryo fibroblasts (MEFs) by treatment with TNF or an agonist antibody to TNFR1. STAT3 activation was inhibited by pharmacological inhibition of the Jak2 tyrosine kinase that associates with TNFR1. To identify STAT3 target genes, global transcriptome analysis by RNA sequencing was performed in wild-type MEFs and MEFs from STAT3 knockout (STAT3KO ) mice that were stimulated with TNF, and the results were validated at the protein level by using multiplex cytokine assays and immunoblotting. After TNF stimulation, STAT3KO MEFs showed greater gene and protein induction of the inflammatory chemokines Ccl2, Cxcl1 and Cxcl10 than WT MEFs. These observations show that, by activating STAT3, TNF selectively modulates expression of a cohort of chemokines that promote inflammation. The greater induction by TNF of chemokines in STAT3KO than WT MEFs suggested that TNF induced an inhibitory protein in WT MEFs. Consistent with this possibility, STAT3 activation by TNFR1 increased the expression of Tnfaip3/A20, a ubiquitin modifying enzyme that inhibits inflammation, in WT MEFs but not in STAT3KO MEFs. Moreover, enforced expression of Tnfaip3/A20 in STAT3KO MEFs suppressed proinflammatory chemokine expression induced by TNF. Our observations identify Tnfaip3/A20 as a new downstream target for STAT3 which limits the induction of Ccl2, Cxcl1 and Cxcl10 and inflammation induced by TNF.


Assuntos
Receptores Tipo I de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa , Animais , Expressão Gênica , Inflamação , Janus Quinase 2/metabolismo , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Fator de Transcrição STAT3/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Am J Transplant ; 22(6): 1550-1563, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35114045

RESUMO

CCR5 KO kidney transplant (KTx) recipients are extraordinarily high alloantibody producers and develop pathology that mimics human antibody-mediated rejection (AMR). C57BL/6 and CCR5 KO mice (H-2b ) were transplanted with A/J kidneys (H-2a ); select cohorts received adoptive cell therapy (ACT) with alloprimed CXCR5+ CD8+ T cells (or control cells) on day 5 after KTx. ACT efficacy was evaluated by measuring posttransplant alloantibody, pathology, and allograft survival. Recipients were assessed for the quantity of CXCR5+ CD8+ T cells and CD8-mediated cytotoxicity to alloprimed IgG+ B cells. Alloantibody titer in CCR5 KO recipients was four-fold higher than in C57BL/6 recipients. The proportion of alloprimed CXCR5+ CD8+ T cells 7 days after KTx in peripheral blood, lymph node, and spleen was substantially lower in CCR5 KO compared to C57BL/6 recipients. In vivo cytotoxicity towards alloprimed IgG+ B cells was also reduced six-fold in CCR5 KO recipients. ACT with alloprimed CXCR5+ CD8+ T cells (but not alloprimed CXCR5- CD8+ or third-party primed CXCR5+ CD8+ T cells) substantially reduced alloantibody titer, ameliorated AMR pathology, and prolonged allograft survival. These results indicate that a deficiency in quantity and function of alloprimed CXCR5+ CD8+ T cells contributes to high alloantibody and AMR in CCR5 KO recipient mice, which can be rescued with ACT.


Assuntos
Transplante de Rim , Animais , Linfócitos T CD8-Positivos , Rejeição de Enxerto/patologia , Imunoglobulina G , Isoanticorpos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
6.
Am Nat ; 200(2): 292-301, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35905407

RESUMO

AbstractAnts disperse oak galls of some cynipid wasp species similarly to how they disperse seeds with elaiosomes. We conducted choice assays in field and laboratory settings with ant-dispersed seeds and wasp-induced galls found in ant nests and found that seed-dispersing ants retrieve these galls as they do myrmecochorous seeds. We also conducted manipulative experiments in which we removed the putative ant-attracting appendages ("kapéllos") from galls and found that ants are specifically attracted to kapéllos. Finally, we compared the chemical composition and histology of ant-attracting appendages on seeds and galls and found that they both have similar fatty acid compositions as well as morphology. We also observed seed-dispersing ants retrieving oak galls to their nests and rodents and birds consuming oak galls that were not retrieved by ants. These results suggest convergence in ant-mediated dispersal between myrmecochorous seeds and oak galls. Based on our observations, a protective advantage for galls retrieved to ant nests seems a more likely benefit than dispersal distance, as has also been suggested for myrmecochorous seeds. These results require reconsideration of established ant-plant research assumptions, as ant-mediated seed and gall dispersal appear strongly convergent and galls may be far more abundant in eastern North American deciduous forests than myrmecochorous seeds.


Assuntos
Formigas , Quercus , Dispersão de Sementes , Animais , Plantas , Sementes
7.
Breast Cancer Res Treat ; 196(3): 571-581, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36280642

RESUMO

PURPOSE: To assess whether crofelemer would prevent chemotherapy-induced diarrhea (CID) diarrhea in patients with HER2-positive, any-stage breast cancer receiving trastuzumab (H), pertuzumab (P), and a taxane (T; docetaxel or paclitaxel), with/without carboplatin (C; always combined with docetaxel rather than paclitaxel). METHODS: Patients scheduled to receive ≥ 3 consecutive TCHP/THP cycles were randomized to crofelemer 125 mg orally twice daily during chemotherapy cycles 1 and 2 or no scheduled prophylactic medication (control). All received standard breakthrough antidiarrheal medication (BTAD) as needed. The primary endpoint was incidence of any-grade CID for ≥ 2 consecutive days. Secondary endpoints were incidence of all-grade and grade 3/4 CID by cycle/stratum; time to onset and duration of CID; stool consistency; use of BTAD; and quality of life (Functional Assessment of Chronic Illness Therapy for Patients With Diarrhea [FACIT-D] score). RESULTS: Fifty-one patients were randomized to crofelemer (n = 26) or control (n = 25). There was no statistically significant difference between arms for the primary endpoint; however, incidence of grade ≥ 2 CID was reduced with crofelemer vs control (19.2% vs 24.0% in cycle 1; 8.0% vs 39.1%, in cycle 2). Patients receiving crofelemer were 1.8 times more likely to see their diarrhea resolved and had less frequent watery diarrhea. CONCLUSION: Despite the choice of primary endpoint being insensitive, crofelemer reduced the incidence and severity of CID in patients with HER2-positive breast cancer receiving P-based therapy. These data are supportive of further testing of crofelemer in CID. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02910219, prospectively registered September 21, 2016.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Trastuzumab , Neoplasias da Mama/etiologia , Docetaxel/efeitos adversos , Receptor ErbB-2 , Qualidade de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Taxoides , Paclitaxel , Diarreia/induzido quimicamente , Diarreia/prevenção & controle , Antineoplásicos/uso terapêutico
8.
Int J Biometeorol ; 66(4): 669-677, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34981199

RESUMO

Climate refugia are anomalous "pockets" of spatially or temporally disjunct environmental conditions that buffer distinct flora and fauna against prevailing climatic conditions. Physiographic landscape features, such as large water bodies, can create these micro-to-macro-scale terrestrial habitats, such as the prevailing westerly winds across the Laurentian Great Lakes that create relatively cooler leeward conditions in spring and relatively warmer leeward conditions in autumn. The leeward Great Lakes climate effects create refugia (popularly known as a "fruit belt") favorable for fruit-bearing trees and shrubs. These fruit belt refugia owe their existence to seasonal inversions whereby spring cooling prevents early flower budding that leaves fruit trees susceptible to late spring killing frosts, and autumn warming prevents early killing frosts. With global climate change, however, warmer summers and milder winters, and corresponding warmer waters, might erode the leeward delaying effect on spring flowering, creating a paradoxical situation in which warming increases the risk of frost damage to plants. We evaluated the success of regional agriculture in the Great Lakes fruit belt to test our hypothesis that warmer spring climate (and concomitant warmer lake waters) correspond with degraded fruit production. We also examined long-term trends in Great Lakes climate conditions. We found that the cold-sensitive fruit tree (apple, grape, peach, and cherry) refugia were destabilized by relatively warmer springs. Moreover, we found several indicators that lake waters are warming across the Great Lakes, which portends negative consequences for agricultural and natural plant communities in the Great Lakes region and in similar "fruit belt" refugia worldwide.


Assuntos
Lagos , Refúgio de Vida Selvagem , Mudança Climática , Frutas , Estações do Ano , Temperatura , Árvores
9.
Cancer ; 127(19): 3622-3630, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34157782

RESUMO

BACKGROUND: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, including palbociclib, are approved to treat hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) and are associated with hematologic toxicity. African American women, who are underrepresented in CDK4/6 inhibitor clinical trials, may experience worse neutropenia because of benign ethnic neutropenia. The authors specifically investigated the hematologic safety of palbociclib in African American women with HR-positive/HER2-negative ABC. METHODS: PALINA was a single-arm, open-label, investigator-initiated study of palbociclib (125 mg daily; 21 days on and 7 days off) plus endocrine therapy (ET) in African American women who had HR-positive/HER2-negative ABC and a baseline absolute neutrophil count ≥1000/mm3 (ClinicalTrials.gov identifier NCT02692755). The primary outcome was the proportion of patients who completed 12 months of therapy without experiencing febrile neutropenia or treatment discontinuation because of neutropenia. Single nucleotide polymorphism analysis was used to assess Duffy polymorphism status. RESULTS: Thirty-five patients received ≥1 dose of palbociclib plus ET; 19 had a Duffy null polymorphism (cytosine/cytosine). There were no reports of febrile neutropenia or permanent study discontinuation because of neutropenia. Significantly more patients with the Duffy null versus the wild-type variant had grade 3 and 4 neutropenia (72.2% vs 23.1%; P = .029) and required a palbociclib dose reduction (55.6% vs 7.7%; P = .008). Patients with the Duffy null versus the wild-type variant had lower overall relative dose intensity (mean ± SD, 81.89% ± 15.87 and 95.67% ± 5.89, respectively; P = .0026) and a lower clinical benefit rate (66.7% and 84.6%, respectively). CONCLUSIONS: These findings suggest that palbociclib is well tolerated in African American women with HR-positive/HER2-negative ABC. Duffy null status may affect the incidence of grade 3 neutropenia, dose intensity, and possibly clinical benefit.


Assuntos
Neoplasias da Mama , Neutropenia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Feminino , Humanos , Neutropenia/induzido quimicamente , Piperazinas , Piridinas , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo
10.
Breast Cancer Res Treat ; 185(3): 863-868, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33400034

RESUMO

PURPOSE: HER2-targeted therapies are associated with cardiotoxicity which is usually asymptomatic and reversible. We report the updated cardiac safety assessment of patients with compromised heart function receiving HER2-targeted therapy for breast cancer, enrolled in the SAFE-HEaRt trial, at a median follow-up of 3.5 years. METHODS: Thirty patients with stage I-IV HER2-positive breast cancer receiving trastuzumab with or without pertuzumab, or ado-trastuzumab emtansine (T-DM1), with asymptomatic LVEF (left ventricular ejection fraction) 40-49%, were started on cardioprotective medications, with the primary endpoint being completion of HER2-targeted therapy without cardiac events (CE) or protocol-defined asymptomatic worsening of LVEF. IRB-approved follow-up assessment included 23 patients. RESULTS: Median follow-up as of June 2020 is 42 months. The study met its primary endpoint with 27 patients (90%) completing their HER2-targeted therapies without cardiac issues. Of the 23 evaluable patients at long-term f/u, 14 had early stage breast cancer, and 9 had metastatic disease, 8 of whom remained on HER2-targeted therapies. One patient developed symptomatic heart failure with no change in LVEF. There were no cardiac deaths. The mean LVEF improved to 52.1% from 44.9% at study baseline, including patients who remained on HER2-targeted therapy, and those who received prior anthracyclines. CONCLUSIONS: Long-term follow-up of the SAFE-HEaRt study continues to provide safety data of HER2-targeted therapy use in patients with compromised heart function. The late development of cardiac dysfunction is uncommon and continued multi-disciplinary oncologic and cardiac care of patients is vital for improved patient outcomes.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Feminino , Seguimentos , Humanos , Receptor ErbB-2/genética , Volume Sistólico , Trastuzumab/efeitos adversos , Função Ventricular Esquerda
11.
PLoS Comput Biol ; 16(11): e1008376, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33232313

RESUMO

The rapidly decreasing cost of gene sequencing has resulted in a deluge of genomic data from across the tree of life; however, outside a few model organism databases, genomic data are limited in their scientific impact because they are not accompanied by computable phenomic data. The majority of phenomic data are contained in countless small, heterogeneous phenotypic data sets that are very difficult or impossible to integrate at scale because of variable formats, lack of digitization, and linguistic problems. One powerful solution is to represent phenotypic data using data models with precise, computable semantics, but adoption of semantic standards for representing phenotypic data has been slow, especially in biodiversity and ecology. Some phenotypic and trait data are available in a semantic language from knowledge bases, but these are often not interoperable. In this review, we will compare and contrast existing ontology and data models, focusing on nonhuman phenotypes and traits. We discuss barriers to integration of phenotypic data and make recommendations for developing an operationally useful, semantically interoperable phenotypic data ecosystem.


Assuntos
Bases de Dados Genéticas , Bases de Conhecimento , Fenômica , Animais , Classificação , Biologia Computacional , Ecossistema , Interação Gene-Ambiente , Humanos , Modelos Biológicos , Modelos Genéticos , Modelos Estatísticos , Fenótipo , Semântica
12.
Nat Methods ; 14(10): 967-970, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28869755

RESUMO

Advances in single-cell technologies have highlighted the prevalence and biological significance of cellular heterogeneity. A critical question researchers face is how to design experiments that faithfully capture the true range of heterogeneity from samples of cellular populations. Here we develop a data-driven approach, illustrated in the context of image data, that estimates the sampling depth required for prospective investigations of single-cell heterogeneity from an existing collection of samples.


Assuntos
Adenocarcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Análise de Célula Única/métodos , Biomarcadores Tumorais , Técnicas de Cultura de Células , Linhagem Celular , Regulação Neoplásica da Expressão Gênica , Humanos
13.
J Surg Res ; 256: 476-485, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32798995

RESUMO

BACKGROUND: Synchronous colorectal cancer liver metastasis (CRLM) has been viewed as being more aggressive and having shorter survival than metachronous disease. Advances in CRLM management led us to examine differences in treatment characteristics of synchronous versus metachronous CRLM patients along with survival and recurrence. MATERIALS AND METHODS: A retrospective review of hepatic resection for CRLM at a tertiary academic medical center was performed for two periods: a historic cohort from 1992 to 2010 (n = 121), and a modern cohort (n = 179) from 2012 to 2018. Clinical variables were compared between the patient groups, and survival outcomes were characterized. RESULTS: Five-year disease-specific survival for the modern synchronous group compared to the historic synchronous group was 71.7% versus 44.3% (P = 0.02). Modern metachronous versus modern synchronous 5-y disease-specific survival rates were 49.8% versus 71.7% (P = 0.31). Compared to the historic cohort, the modern one had significantly different timing of hepatic resection (P < 0.01) with increased use of liver-first (30.1% versus 7.5%) and simultaneous liver-colon resections (24.1% versus 10.4%), along with greater use of neoadjuvant chemotherapy (96.4% versus 65.6%; P < 0.01). Significantly more patients in the modern synchronous cohort had disease-free or alive-with-disease status at last follow-up, compared to the historic group (P < 0.01), and experienced less disease recurrence (62.7% versus 77.6%; P < 0.05). CONCLUSIONS: Modern synchronous CRLM patients who underwent hepatic resection experienced significantly improved survival compared to a historic cohort. We postulate that increased use of neoadjuvant chemotherapy and liver-first/simultaneous liver-colon resections in the modern synchronous cohort contributed to improved survival.


Assuntos
Neoplasias Colorretais/patologia , Hepatectomia/estatística & dados numéricos , Neoplasias Hepáticas/mortalidade , Terapia Neoadjuvante/estatística & dados numéricos , Recidiva Local de Neoplasia/epidemiologia , Adulto , Idoso , Quimioterapia Adjuvante/estatística & dados numéricos , Colectomia/estatística & dados numéricos , Colo/patologia , Colo/cirurgia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/terapia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos , Taxa de Sobrevida
14.
J Surg Oncol ; 122(2): 204-211, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32291778

RESUMO

BACKGROUND AND OBJECTIVES: We classified the extent of mesenteric mass (MM) involvement that predicts challenging mesenteric lymph node dissection (mLND) by minimally invasive surgery (MIS) for ileal neuroendocrine tumors (i-NETs). METHODS: Patients who underwent surgery for i-NETs were retrospectively reviewed. MM involvement was classified as region-0: no MM; region-1: >2 cm from the origins of the ileocolic artery/vein; region-2: ≤2 cm from the origins; and region-3: more proximal superior mesenteric artery/vein. Logistic regression analysis was used to evaluate the predictive value of MM regions for gross positive mesenteric margin (mR2) and/or conversion among the MIS cohort. The open surgery cohort was used as a reference for mR2 rates. RESULTS: Of 108 patients, 83 patients (77%) underwent MIS. MMs in region-2 and region-3 were independent risk factors for mR2 and/or conversion (odds ratio [95% confidence interval]: 4.25 [1.17-16.4] and 8.51 × 107 [11.0-], respectively, against regions-0 and 1]. mR2 rates of MIS and open surgery cohorts per region did not differ significantly (4% and 7% for regions-0 and 1; 17% and 25% for region-2; and 100% and 83% for region-3). CONCLUSIONS: The novel stratification of MM regions was predictive of challenging mLND by MIS. Surgeons should have a low threshold for conversion for MMs in proximal regions.


Assuntos
Neoplasias do Íleo/patologia , Neoplasias do Íleo/cirurgia , Linfonodos/patologia , Linfonodos/cirurgia , Mesentério/patologia , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/cirurgia , Estudos de Coortes , Humanos , Excisão de Linfonodo , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Valor Preditivo dos Testes , Estudos Retrospectivos
15.
J Surg Oncol ; 121(2): 330-336, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31828813

RESUMO

BACKGROUND AND OBJECTIVES: We developed objective measurements of preoperative and residual tumor volume, and debulking rate, to evaluate their prognostic value for neuroendocrine liver metastasis (NELM). METHODS: Seventy-three patients who underwent surgery for NELM were analyzed retrospectively. Indices of preoperative and postoperative residual tumor volume (pre-volume index [VI] and post-VI) were calculated as the sum of the cubes of individual tumor diameters on preoperative and postoperative imaging, respectively. The debulking rate (%) was calculated as 100 - 100 × post-VI/pre-VI. The classification and regression trees method was used to classify pre-VI and post-VI. RESULTS: Overall survival (OS) was discriminated by preoperative tumor volume (5-year OS rates, 87.8% for low pre-VI and 60.1% for high pre-VI; P = .037) and residual tumor volume (5-year OS rates, 88.1% for low post-VI and 24.8% for high post-VI; P < .001). In contrast, debulking rates of 100%, ≥90%, and <90% did not discriminate OS (5-year OS rates, 88.0%, 61.9%, and 58.9%, respectively, not significant). In multivariate analysis, residual tumor volume (high post-VI, hazard ratio, 6.40; 95% confidence interval, 1.45-32.3) was an independent prognostic factor for OS. CONCLUSIONS: Objective measurement of tumor volume demonstrates that residual tumor volume is prognostic after surgery for NELM.

16.
J Immunol ; 201(12): 3731-3740, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30397035

RESUMO

Humoral alloimmunity negatively impacts both short- and long-term cell and solid organ transplant survival. We previously reported that alloantibody-mediated rejection of transplanted hepatocytes is critically dependent on host macrophages. However, the effector mechanism(s) of macrophage-mediated injury to allogeneic liver parenchymal cells is not known. We hypothesized that macrophage-mediated destruction of allogeneic hepatocytes occurs by cell-cell interactions requiring FcγRs. To examine this, alloantibody-dependent hepatocyte rejection in CD8-depleted wild-type (WT) and Fcγ-chain knockout (KO; lacking all functional FcγR) transplant recipients was evaluated. Alloantibody-mediated hepatocellular allograft rejection was abrogated in recipients lacking FcγR compared with WT recipients. We also investigated anti-FcγRI mAb, anti-FcγRIII mAb, and inhibitors of intracellular signaling (to block phagocytosis, cytokines, and reactive oxygen species [ROS]) in an in vitro alloantibody-dependent, macrophage-mediated hepatocytoxicity assay. Results showed that in vitro alloantibody-dependent, macrophage-mediated hepatocytotoxicity was critically dependent on FcγRs and ROS. The adoptive transfer of WT macrophages into CD8-depleted FcγR-deficient recipients was sufficient to induce alloantibody-mediated rejection, whereas adoptive transfer of macrophages from Fcγ-chain KO mice or ROS-deficient (p47 KO) macrophages was not. These results provide the first evidence, to our knowledge, that alloantibody-dependent hepatocellular allograft rejection is mediated by host macrophages through FcγR signaling and ROS cytotoxic effector mechanisms. These results support the investigation of novel immunotherapeutic strategies targeting macrophages, FcγRs, and/or downstream molecules, including ROS, to inhibit humoral immune damage of transplanted hepatocytes and perhaps other cell and solid organ transplants.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Rejeição de Enxerto/imunologia , Hepatócitos/imunologia , Macrófagos/imunologia , Receptores de IgG/metabolismo , ATPases Associadas a Diversas Atividades Celulares/genética , Animais , Células Cultivadas , Citotoxicidade Imunológica , DNA Helicases/genética , Humanos , Isoanticorpos/metabolismo , Transplante de Fígado , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Receptores de IgG/genética , Transdução de Sinais
17.
J Surg Oncol ; 120(8): 1311-1317, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613999

RESUMO

BACKGROUND AND OBJECTIVES: Ileal neuroendocrine tumors (i-NETs) frequently metastasize to mesenteric lymph nodes and the liver. Regional lymphadenopathy is associated with desmoplasia of the mesentery forming a large mesenteric mass (LMM). Although the latest American Joint Committee on Cancer TNM staging (8th edition) defined LMM >2 cm as N2, the prognostic impact of LMM is ill-defined. We evaluated whether LMM is prognostic for patients with i-NETs. METHODS: This single-institution, retrospective cohort study included 106 patients who underwent resection of i-NETs between 2007 and 2018. Overall survival (OS) and liver progression-free survival (LPFS) were compared between patients with and without LMM. RESULTS: LMM was present in 66 patients (62%) and was not associated with the presence or absence of liver metastasis (P = .969) or the extent of liver involvement (P = .938). OS and LPFS differed significantly between patients with and without LMM (5-year OS rates of 64.8% and 92.9%, respectively, P = .011; 3-year LPFS rates of 45.3% and 67.5%, respectively, P = .025). In multivariate analysis, LMM was an independent prognostic factor for both OS (hazard ratio: 4.69, 95% confidence interval: 1.63-17.6) and LPFS (1.99, 1.08-3.88). CONCLUSION: LMM >2 cm is prognostic for OS and LPFS and represents aggressive tumor biology.


Assuntos
Neoplasias do Íleo/mortalidade , Neoplasias do Íleo/patologia , Linfonodos/patologia , Mesentério/patologia , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Idoso , Estudos de Coortes , Feminino , Humanos , Neoplasias do Íleo/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/cirurgia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos
18.
HPB (Oxford) ; 21(5): 515-523, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30527517

RESUMO

BACKGROUND: Variation in the management of PNETs exist due to the limited high-level evidence to guide clinical practice. The aim of this work is to generate consensus guidelines with a Delphi process for managing PNETs. METHODS: A panel of experts reviewed the surgical literature and scored a set of clinical case statements using a web-based survey to identify areas of agreement and disagreement. Results of the survey were discussed after each round of review. This cycle was repeated until no further likelihood of reaching consensus existed. RESULTS: Twenty-two case statements related to surgical indications, preoperative biopsy, extent of resection, type of surgery, and tumor location were scored. Using a pre-defined definition of consensus, the panel achieved consensus on the following: i) resection is not recommended for <1 cm lesions; ii) resection is recommended for lesions greater than 2 cm; iii) lymph node dissection is recommended for radiographically-suspicious nodes with splenectomy for distal lesions; iv) tumor enucleation and central pancreatectomy are acceptable when technically feasible. No consensus was reached regarding issues of preoperative biopsy or 1-2 cm tumors. CONCLUSIONS: Using a structured, validated system for identifying consensus, an expert panel identified areas of agreement regarding critical management decisions for patients with PNET. Issues without consensus warrant additional clinical investigation.


Assuntos
Tumores Neuroectodérmicos Primitivos/terapia , América , Biópsia , Consenso , Técnica Delphi , Humanos , Excisão de Linfonodo , Tumores Neuroectodérmicos Primitivos/patologia , Sociedades Médicas , Esplenectomia
19.
Ecol Lett ; 21(5): 724-733, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29575384

RESUMO

Vegetative dormancy, that is the temporary absence of aboveground growth for ≥ 1 year, is paradoxical, because plants cannot photosynthesise or flower during dormant periods. We test ecological and evolutionary hypotheses for its widespread persistence. We show that dormancy has evolved numerous times. Most species displaying dormancy exhibit life-history costs of sprouting, and of dormancy. Short-lived and mycoheterotrophic species have higher proportions of dormant plants than long-lived species and species with other nutritional modes. Foliage loss is associated with higher future dormancy levels, suggesting that carbon limitation promotes dormancy. Maximum dormancy duration is shorter under higher precipitation and at higher latitudes, the latter suggesting an important role for competition or herbivory. Study length affects estimates of some demographic parameters. Our results identify life historical and environmental drivers of dormancy. We also highlight the evolutionary importance of the little understood costs of sprouting and growth, latitudinal stress gradients and mixed nutritional modes.


Assuntos
Evolução Biológica , Herbivoria , Demografia , Flores
20.
Oncologist ; 22(1): 107-114, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27821793

RESUMO

PURPOSE: Tumor levels of thymidylate synthase (TS), a target of 5-fluorouracil (5-FU)-based chemotherapy for colorectal cancer, have been studied as a predictive or prognostic biomarker with mixed results. PATIENTS AND METHODS: Tumor TS levels were prospectively evaluated in two adjuvant therapy trials for patients with resected stage II or III colon cancer. TS expression was determined by standard immunohistochemistry and by automated quantitative analysis. Tumor mismatch repair deficiency (MMR-D) and BRAF c.1799T > A (p.V600E) mutation status were also examined. Relationships between tumor TS, MMR-D, and BRAF mutation status, overall survival (OS), and disease-free survival (DFS) were investigated in the subset of stage III patients. RESULTS: Patients whose tumors demonstrated high TS expression experienced better treatment outcomes, with DFS hazard ratio (HR) = 0.67, 95% confidence interval (CI) = 0.53, 0.84; and OS HR = 0.68, 95% CI = 0.53, 0.88, for high versus low TS expression, respectively. No significant interaction between TS expression and stage was observed (DFS: interaction HR = 0.94; OS: interaction HR = 0.94). Tumors with high TS expression were more likely to demonstrate MMR-D (22.2% vs. 12.8%; p = .0003). Patients whose tumors demonstrated both high TS and MMR-D had a 7-year DFS of 77%, compared with 58% for those whose tumors had low TS and were non-MMR-D (log-rank p = .0006). Tumor TS expression did not predict benefit of a particular therapeutic regimen. CONCLUSION: This large prospective analysis showed that high tumor TS levels were associated with improved DFS and OS following adjuvant therapy for colon cancer, although tumor TS expression did not predict benefit of 5-FU-based chemotherapy. The Oncologist 2017;22:107-114Implications for Practice: This study finds that measurement of tumor levels of thymidylate synthase is not helpful in assigning specific adjuvant treatment for colorectal cancer. It also highlights the importance of using prospective analyses within treatment clinical trials as the optimal method of determining biomarker utility.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Timidilato Sintase/genética , Idoso , Biomarcadores Tumorais/biossíntese , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Timidilato Sintase/antagonistas & inibidores , Resultado do Tratamento
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