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1.
Adv Radiat Oncol ; 9(2): 101337, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38405310

ABSTRACT

Purpose: Recent advances to preserve neurocognitive function in patients treated for brain metastases include stereotactic radiosurgery, hippocampal avoidance whole brain radiation therapy (WBRT), and memantine administration. The hippocampus, corpus callosum, fornix, and amygdala are key neurocognitive substructures with a low propensity for brain metastases. Herein, we report our preliminary experience using a "memory-avoidance" WBRT (MA-WBRT) approach that spares these substructures for patients with >15 brain metastases. Methods and Materials: Ten consecutive patients treated with MA-WBRT on a phase 2 clinical trial were reviewed. In each patient, the hippocampi, amygdalae, corpus callosum, and fornix were contoured. Patients were not eligible for MA-WBRT if they had metastases in these substructures. A memory-avoidance region was created using a 5-mm volumetric expansion around these substructures. Hotspots were avoided in the hypothalamus and pituitary gland. Coverage of brain metastases was prioritized over memory avoidance dose constraints. Dose constraints for these avoidance structures included a D100% ≤ 9 Gy and D0.03 cm3 ≤ 16 Gy (variation acceptable to 20 Gy). LINAC-based volumetric modulated arc therapy plans were generated for a prescription dose of 30 Gy in 10 fractions. Results: On average, the memory avoidance structure volume was 37.1 cm3 (range, 25.2-44.6 cm3), occupying 2.5% of the entire whole brain target volume. All treatment plans met the D100% dose constraint, and 8 of 10 plans met the D0.03 cm3 constraint, with priority given to tumor coverage for the remaining 2 cases. Target coverage (D98% > 25 Gy) and homogeneity (D2% ≤ 37.5 Gy) were achieved for all plans. Conclusions: Modern volumetric modulated arc therapy techniques allow for sparing of the hippocampus, amygdala, corpus callosum, and fornix with good target coverage and homogeneity. After enrollment is completed, quality of life and cognitive data will be evaluated to assess the efficacy of MA-WBRT to mitigate declines in quality of life and cognition after whole brain radiation.

2.
Int J Radiat Oncol Biol Phys ; 118(4): 979-985, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-37871886

ABSTRACT

PURPOSE: The current standard for meningioma treatment planning involves magnetic resonance imaging-based guidance. Somatostatin receptor ligands such as 68Ga-DOTATATE are being explored for meningioma treatment planning due to near-universal expression of somatostatin receptors 1 and 2 in meningioma tissue. We hypothesized that 68Ga-DOTATATE positron emission tomography (PET)-guided treatment management for patients with meningiomas is safe and effective and can identify which patients benefit most from adjuvant radiation therapy. METHODS AND MATERIALS: A single-institution prospective registry study was created for inclusion of patients with intracranial meningiomas who received a 68Ga-DOTATATE PET/CT to assist with radiation oncologist decision making. Patients who received a PET scan from January 1, 2018, to February 25, 2022, were eligible for inclusion. RESULTS: Of the 60 patients included, 40%, 47%, and 5% had World Health Organization grades 1, 2, and 3 meningiomas, respectively, and 8% (5 patients) had no grade assigned. According to Radiation Therapy Oncology Group 0539 criteria, 22%, 72%, and 7% were categorized as high, intermediate, and low risk, respectively. After completing their PET scans, 48 patients, 11 patients, and 1 patient proceeded with radiation therapy, observation, and redo craniotomy, respectively. The median follow-up for the entire cohort was 19.5 months. Of the 3 patients (5%) who experienced local failure between 9.2 and 28.5 months after diagnosis, 2 had PET-avid disease in their postoperative cavity and elected for observation before recurrence, and 1 high-risk patient with multifocal disease experienced local failure 2 years after a second radiation course and multiple previous recurrences. Notably, 5 patients did not have any local PET uptake and were observed; none of these patients experienced recurrence. Only 1 grade 3 toxicity was attributed to PET-guided radiation. CONCLUSIONS: This study examined one of the largest known populations of patients with intracranial meningiomas followed by physicians who used 68Ga-DOTATATE PET-guided therapy. Incorporating 68Ga-DOTATATE PET into future trials may assist with clinician decision making and improve patient outcomes.


Subject(s)
Meningeal Neoplasms , Meningioma , Organometallic Compounds , Radionuclide Imaging , Humans , Meningioma/diagnostic imaging , Meningioma/radiotherapy , Positron Emission Tomography Computed Tomography , Gallium Radioisotopes , Positron-Emission Tomography/methods , Meningeal Neoplasms/diagnostic imaging , Meningeal Neoplasms/radiotherapy
3.
J Leukoc Biol ; 114(5): 487-506, 2023 10 26.
Article in English | MEDLINE | ID: mdl-36869821

ABSTRACT

Innate immune cells represent the first line of cellular immunity, comprised of both circulating and tissue-resident natural killer cells and innate lymphoid cells. These innate lymphocytes arise from a common CD34+ progenitor that differentiates into mature natural killer cells and innate lymphoid cells. The successive stages in natural killer cell maturation are characterized by increased lineage restriction and changes to phenotype and function. Mechanisms of human natural killer cell development have not been fully elucidated, especially the role of signals that drive the spatial localization and maturation of natural killer cells. Cytokines, extracellular matrix components, and chemokines provide maturation signals and influence the trafficking of natural killer cell progenitors to peripheral sites of differentiation. Here we present the latest advances in our understanding of natural killer and innate lymphoid cell development in peripheral sites, including secondary lymphoid tissues (i.e. tonsil). Recent work in the field has provided a model for the spatial distribution of natural killer cell and innate lymphoid cell developmental intermediates in tissue and generated further insights into the developmental niche. In support of this model, future studies using multifaceted approaches seek to fully map the developmental trajectory of human natural killer cells and innate lymphoid cells in secondary lymphoid tissues.


Subject(s)
Immunity, Innate , Killer Cells, Natural , Humans , Cell Differentiation , Cytokines/metabolism , Palatine Tonsil/metabolism
4.
Cell Rep ; 42(1): 111937, 2023 01 31.
Article in English | MEDLINE | ID: mdl-36640314

ABSTRACT

Group 1 innate lymphoid cells (ILCs) comprise a heterogeneous family of cytotoxic natural killer (NK) cells and ILC1s. We identify a population of "liver-type" ILC1s with transcriptional, phenotypic, and functional features distinct from those of conventional and liver-resident NK cells as well as from other previously described human ILC1 subsets. LT-ILC1s are CD49a+CD94+CD200R1+, express the transcription factor T-BET, and do not express the activating receptor NKp80 or the transcription factor EOMES. Similar to NK cells, liver-type ILC1s produce IFN-γ, TNF-α, and GM-CSF; however, liver-type ILC1s also produce IL-2 and lack perforin and granzyme-B. Liver-type ILC1s are expanded in cirrhotic liver tissues, and they can be produced from blood-derived ILC precursors in vitro in the presence of TGF-ß1 and liver sinusoidal endothelial cells. Cells with similar signature and function can also be found in tonsil and intestinal tissues. Collectively, our study identifies and classifies a population of human cross-tissue ILC1s.


Subject(s)
Immunity, Innate , Lymphocytes , Humans , Endothelial Cells , Killer Cells, Natural , Liver , Transcription Factors , Sequence Analysis, RNA
5.
Biomedicines ; 10(9)2022 Sep 07.
Article in English | MEDLINE | ID: mdl-36140312

ABSTRACT

Brain metastases are a devastating sequela of common primary cancers (e.g., lung, breast, and skin) and have limited effective therapeutic options. Previously, systemic chemotherapy failed to demonstrate significant benefit in patients with brain metastases, but in recent decades, targeted therapies and more recently immune checkpoint inhibitors (ICIs) have yielded promising results in preclinical and clinical studies. Furthermore, there is significant interest in harnessing the immunomodulatory effects of radiotherapy (RT) to synergize with ICIs. Herein, we discuss studies evaluating the impact of RT dose and fractionation on the immune response, early studies supporting the synergistic interaction between RT and ICIs, and ongoing clinical trials assessing the benefit of combination therapy in patients with brain metastases.

6.
Blood Cancer Discov ; 3(2): 154-169, 2022 03 01.
Article in English | MEDLINE | ID: mdl-35247900

ABSTRACT

Extranodal natural killer/T-cell lymphoma (ENKTL) is an aggressive, rare lymphoma of natural killer (NK) cell origin with poor clinical outcomes. Here we used phenotypic and molecular profiling, including epigenetic analyses, to investigate how ENKTL ontogeny relates to normal NK-cell development. We demonstrate that neoplastic NK cells are stably, but reversibly, arrested at earlier stages of NK-cell maturation. Genes downregulated in the most epigenetic immature tumors were associated with polycomb silencing along with genomic gain and overexpression of EZH2. ENKTL cells exhibited genome-wide DNA hypermethylation. Tumor-specific DNA methylation gains were associated with polycomb-marked regions, involving extensive gene silencing and loss of transcription factor binding. To investigate therapeutic targeting, we treated novel patient-derived xenograft (PDX) models of ENKTL with the DNA hypomethylating agent, 5-azacytidine. Treatment led to reexpression of NK-cell developmental genes, phenotypic NK-cell differentiation, and prolongation of survival. These studies lay the foundation for epigenetic-directed therapy in ENKTL. SIGNIFICANCE: Through epigenetic and transcriptomic analyses of ENKTL, a rare, aggressive malignancy, along with normal NK-cell developmental intermediates, we identified that extreme DNA hypermethylation targets genes required for NK-cell development. Disrupting this epigenetic blockade in novel PDX models led to ENKTL differentiation and improved survival. This article is highlighted in the In This Issue feature, p. 85.


Subject(s)
Lymphoma, Extranodal NK-T-Cell , Natural Killer T-Cells , Epigenomics , Gene Expression Profiling , Humans , Killer Cells, Natural/pathology , Lymphoma, Extranodal NK-T-Cell/drug therapy , Natural Killer T-Cells/pathology
7.
J Immunol ; 207(6): 1672-1682, 2021 09 15.
Article in English | MEDLINE | ID: mdl-34417259

ABSTRACT

NK cells are known to be developmentally blocked and functionally inhibited in patients with acute myeloid leukemia (AML), resulting in poor clinical outcomes. In this study, we demonstrate that whereas NK cells are inhibited, closely related type 1 innate lymphoid cells (ILC1s) are enriched in the bone marrow of leukemic mice and in patients with AML. Because NK cells and ILC1s share a common precursor (ILCP), we asked if AML acts on the ILCP to alter developmental potential. A combination of ex vivo and in vivo studies revealed that AML skewing of the ILCP toward ILC1s and away from NK cells represented a major mechanism of ILC1 generation. This process was driven by AML-mediated activation of the aryl hydrocarbon receptor (AHR), a key transcription factor in ILCs, as inhibition of AHR led to decreased numbers of ILC1s and increased NK cells in the presence of AML. These results demonstrate a mechanism of ILC developmental skewing in AML and support further preclinical study of AHR inhibition in restoring normal NK cell development and function in the setting of AML.


Subject(s)
Cell Differentiation/immunology , Immunity, Innate , Killer Cells, Natural/immunology , Leukemia, Myeloid, Acute/immunology , Animals , Azo Compounds/pharmacology , Basic Helix-Loop-Helix Transcription Factors/agonists , Basic Helix-Loop-Helix Transcription Factors/antagonists & inhibitors , Basic Helix-Loop-Helix Transcription Factors/metabolism , Bone Marrow/immunology , Carbazoles/pharmacology , Cell Differentiation/drug effects , Cells, Cultured , Disease Models, Animal , Female , Humans , Leukemia, Myeloid, Acute/blood , Lymphocyte Count , Male , Mice , Mice, Inbred C57BL , Pyrazoles/pharmacology , Receptors, Aryl Hydrocarbon/agonists , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Receptors, Aryl Hydrocarbon/metabolism , Signal Transduction/drug effects
8.
J Natl Compr Canc Netw ; 20(6): 644-652.e2, 2021 Jun 10.
Article in English | MEDLINE | ID: mdl-34111839

ABSTRACT

BACKGROUND: The incidence of squamous cell carcinoma of the anus (SCCA) is increasing, particularly among the elderly (age ≥65 years). We sought to compare patterns of care for the treatment of SCCA in elderly versus nonelderly patients. METHODS: Data for patients with stages I-III SCCA diagnosed from 2004 through 2015 were obtained from the National Cancer Database. Patients were categorized as having received standard-of-care (SOC) chemoradiation (CRT) with multiagent chemotherapy, non-SOC therapy, palliative therapy, or no treatment. Differences in treatment groups were tested using the chi-square test. We used logistic regression to identify predictors of SOC CRT and multiagent versus single-agent chemotherapy in patients receiving CRT. Propensity score matching was used to compare overall survival (OS) in elderly patients receiving multiagent versus single-agent chemotherapy for those receiving CRT. RESULTS: We identified 9,156 elderly and 17,640 nonelderly patients. A lower proportion of elderly versus nonelderly patients (54.5% vs 65.0%; P<.0001) received SOC CRT than other treatments or no treatment. In multivariate analysis, elderly patients were 38% less likely than nonelderly patients to receive SOC CRT (odds ratio, 0.62; 95% CI, 0.58-0.65; P<.0001). A higher proportion of the elderly were treated with single-agent versus multiagent chemotherapy (16.9% vs 11.8%; P<.0001), which resulted in a >1.5-fold increase in the likelihood of elderly patients receiving single-agent chemotherapy (odds ratio, 1.52; 95% CI, 1.39-1.66) in multivariate analysis. After propensity score matching, 3-year OS was higher in elderly patients who received CRT with multiagent versus single-agent chemotherapy (77.1% vs 67.5%; hazard ratio, 0.78; 95% CI, 0.68-0.89; P=.0002). CONCLUSIONS: In this comprehensive study of patients with stages I-III SCCA, elderly patients were less likely than nonelderly patients to receive SOC CRT. The low proportion of elderly patients receiving SOC CRT with multiagent chemotherapy for localized anal cancer suggests that the optimal treatment approach for this vulnerable population remains undefined.

9.
Hosp Pediatr ; 11(6): 636-649, 2021 06.
Article in English | MEDLINE | ID: mdl-34021029

ABSTRACT

CONTEXT: Pediatric family-centered rounds (FCRs) have been shown to have benefits in staff satisfaction, teaching, and rounding efficiency, but no systematic review has been conducted to explicitly examine the humanistic impact of FCRs. OBJECTIVE: The objective with this review is to determine if FCRs promote the core values of humanism in medicine by answering the question, "Do FCRs promote humanistic pediatric care?" DATA SOURCES: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a search of PubMed, Web of Science, Cumulative Index of Nursing and Allied Health Literature, and Dissertation Abstracts for peer-reviewed pediatric studies through January 1, 2020. We used search terms including FCRs, communication, humanism, and the specific descriptors in the Gold Foundation's definition of humanism. STUDY SELECTION: Abstracts (n = 1003) were assessed for 5 primary outcomes: empathy, enhanced communication, partnership, respect, and satisfaction and service. We evaluated 158 full-text articles for inclusion, reconciling discrepancies through an iterative process. DATA EXTRACTION: Data abstraction, thematic analysis, and conceptual synthesis were conducted on 29 studies. RESULTS: Pediatric family-centered rounds (FCRs) improved humanistic outcomes within all 5 identified themes. Not all studies revealed improvement within every category. The humanistic benefits of FCRs are enhanced through interventions targeted toward provider-family barriers, such as health literacy. Patients with limited English proficiency or disabilities or who were receiving intensive care gained additional benefits. CONCLUSIONS: Pediatric FCRs promote humanistic outcomes including increased empathy, partnership, respect, service, and communication. Limitations included difficulty in defining humanism, variable implementation, and inconsistent reporting of humanistic outcomes. Future efforts should include highlighting FCR's humanistic benefits, universal implementation, and adapting FCRs to pandemics such as coronavirus disease 2019.


Subject(s)
Attitude of Health Personnel , Humanism , Pediatrics/methods , Professional-Family Relations , Teaching Rounds/methods , Child , Child, Hospitalized , Communication , Empathy , Humans
10.
J Immunol ; 205(10): 2679-2693, 2020 11 15.
Article in English | MEDLINE | ID: mdl-33020148

ABSTRACT

Human NK cells develop in tonsils through discrete NK cell developmental intermediates (NKDIs), yet the mechanistic regulation of this process is unclear. We demonstrate that Notch activation in human tonsil-derived stage 3 (CD34-CD117+CD94-NKp80-) and 4A (CD34-CD117+/-CD94+NKp80-) NKDIs promoted non-NK innate lymphoid cell differentiation at the expense of NK cell differentiation. In contrast, stage 4B (CD34-CD117+/-CD94+NKp80+) NKDIs were NK cell lineage committed despite Notch activation. Interestingly, whereas NK cell functional maturation from stage 3 and 4A NKDIs was independent of Notch activation, the latter was required for high NKp80 expression and a stage 4B-like phenotype by the NKDI-derived NK cells. The Notch-dependent effects required simultaneous engagement with OP9 stromal cells and were also stage-specific, with NOTCH1 and NOTCH2 receptors regulating stage 3 NKDIs and NOTCH1 primarily regulating stage 4A NKDIs. These data establish stage-specific and stromal-dependent roles for Notch in regulating human NK cell developmental plasticity and maturation.


Subject(s)
Cell Differentiation/immunology , Killer Cells, Natural/physiology , Receptor, Notch1/metabolism , Receptor, Notch2/metabolism , Cell Plasticity/immunology , Cells, Cultured , Humans , Immunity, Innate , Lectins, C-Type/metabolism , Palatine Tonsil/cytology , Palatine Tonsil/immunology , Primary Cell Culture , Receptors, Natural Killer Cell/metabolism , Signal Transduction/immunology
11.
Clin Cancer Res ; 26(3): 669-678, 2020 02 01.
Article in English | MEDLINE | ID: mdl-31672772

ABSTRACT

PURPOSE: EGF-like domain 7 (EGFL7) is a secreted protein and recently has been shown to play an important role in acute myeloid leukemia (AML); however, the underlying mechanism by which EGFL7 promotes leukemogenesis is largely unknown. EXPERIMENTAL DESIGN: Using an antibody interaction array, we measured the ability of EGFL7 to bind directly approximately 400 proteins expressed by primary AML blasts. Primary patient samples were stimulated in vitro with recombinant EGFL7 (rEGFL7) or anti-EGFL7 blocking antibody to assess alterations in downstream signaling and the ability to effect blast differentiation and survival. We treated three independent AML models with anti-EGFL7 or IgG1 control to determine whether anti-EGFL7 could prolong survival in vivo. RESULTS: We found EGFL7 significantly binds several signaling proteins important for normal and malignant hematopoiesis including NOTCH. Stimulation of AML blasts with rEGFL7 reduced NOTCH intracellular domain and NOTCH target gene expression while treatment with an anti-EGFL7 blocking antibody resulted in reactivation of NOTCH signaling, increased differentiation, and apoptosis. Competitive ligand-binding assays showed rEGFL7 inhibits DELTA-like (DLL) 4-mediated NOTCH activation while anti-EGFL7 combined with DLL4 significantly increased NOTCH activation and induced apoptosis. Using three different AML mouse models, we demonstrated that in vivo treatment with anti-EGFL7 alone results in increased survival. CONCLUSIONS: Our data demonstrate that EGFL7 contributes to NOTCH silencing in AML by antagonizing canonical NOTCH ligand binding. Reactivation of NOTCH signaling in vivo using anti-EGFL7 results in prolonged survival of leukemic mice, supporting the use of EGFL7 as a novel therapeutic target in AML.


Subject(s)
Antibodies, Monoclonal, Humanized/pharmacology , Calcium-Binding Proteins/metabolism , EGF Family of Proteins/metabolism , Leukemia, Myeloid, Acute/pathology , Receptors, Notch/antagonists & inhibitors , Animals , Apoptosis , Calcium-Binding Proteins/genetics , Cell Differentiation , Cell Line, Tumor , Cell Proliferation , Disease Models, Animal , EGF Family of Proteins/genetics , Female , Humans , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Mice, SCID , Receptors, Notch/metabolism , Signal Transduction
12.
Cancer Discov ; 9(10): 1422-1437, 2019 10.
Article in English | MEDLINE | ID: mdl-31340937

ABSTRACT

Blockade of PD-L1 expression on tumor cells via anti-PD-L1 monoclonal antibody (mAb) has shown great promise for successful cancer treatment by overcoming T-cell exhaustion; however, the function of PD-L1 on natural killer (NK) cells and the effects of anti-PD-L1 mAb on PD-L1+ NK cells remain unknown. Moreover, patients with PD-L1 - tumors can respond favorably to anti-PD-L1 mAb therapy for unclear reasons. Here, we show that some tumors can induce PD-L1 on NK cells via AKT signaling, resulting in enhanced NK-cell function and preventing cell exhaustion. Anti-PD-L1 mAb directly acts on PD-L1+ NK cells against PD-L1 - tumors via a p38 pathway. Combination therapy with anti-PD-L1 mAb and NK cell-activating cytokines significantly improves the therapeutic efficacy of human NK cells against PD-L1 - human leukemia when compared with monotherapy. Our discovery of a PD-1-independent mechanism of antitumor efficacy via the activation of PD-L1+ NK cells with anti-PD-L1 mAb offers new insights into NK-cell activation and provides a potential explanation as to why some patients lacking PD-L1 expression on tumor cells still respond to anti-PD-L1 mAb therapy. SIGNIFICANCE: Targeting PD-L1 expressed on PD-L1+ tumors with anti-PD-L1 mAb successfully overcomes T-cell exhaustion to control cancer, yet patients with PD-L1 - tumors can respond to anti-PD-L1 mAb. Here, we show that anti-PD-L1 mAb activates PD-L1+ NK cells to control growth of PD-L1 - tumors in vivo, and does so independent of PD-1.This article is highlighted in the In This Issue feature, p. 1325.


Subject(s)
Antineoplastic Agents, Immunological/pharmacology , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/metabolism , Cytotoxicity, Immunologic/drug effects , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Neoplasms/immunology , Neoplasms/metabolism , Animals , Antibodies, Monoclonal, Humanized/pharmacology , Biomarkers, Tumor , Cell Line, Tumor , Cytokines/metabolism , Gene Expression , Humans , Immunophenotyping , Killer Cells, Natural/drug effects , Lymphocyte Activation , Neoplasms/drug therapy , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction
13.
Nat Immunol ; 20(1): 10-17, 2019 01.
Article in English | MEDLINE | ID: mdl-30538328

ABSTRACT

Interleukin 15 (IL-15) is one of the most important cytokines that regulate the biology of natural killer (NK) cells1. Here we identified a signaling pathway-involving the serine-threonine kinase AKT and the transcription factor XBP1s, which regulates unfolded protein response genes2,3-that was activated in response to IL-15 in human NK cells. IL-15 induced the phosphorylation of AKT, which led to the deubiquitination, increased stability and nuclear accumulation of XBP1s protein. XBP1s bound to and recruited the transcription factor T-BET to the gene encoding granzyme B, leading to increased transcription. XBP1s positively regulated the cytolytic activity of NK cells against leukemia cells and was also required for IL-15-mediated NK cell survival through an anti-apoptotic mechanism. Thus, the newly identified IL-15-AKT-XBP1s signaling pathway contributes to enhanced effector functions and survival of human NK cells.


Subject(s)
Interleukin-15/metabolism , Killer Cells, Natural/immunology , Proto-Oncogene Proteins c-akt/metabolism , T-Box Domain Proteins/metabolism , X-Box Binding Protein 1/metabolism , Cell Survival , Cells, Cultured , Cytotoxicity, Immunologic , Gene Expression Regulation , Granzymes/genetics , Granzymes/metabolism , Humans , Phosphorylation , Protein Binding , Protein Stability , Signal Transduction , Ubiquitination , Unfolded Protein Response
15.
Immunity ; 49(3): 464-476.e4, 2018 09 18.
Article in English | MEDLINE | ID: mdl-30193847

ABSTRACT

According to the established model of murine innate lymphoid cell (ILC) development, helper ILCs develop separately from natural killer (NK) cells. However, it is unclear how helper ILCs and NK cells develop in humans. Here we elucidated key steps of NK cell, ILC2, and ILC3 development within human tonsils using ex vivo molecular and functional profiling and lineage differentiation assays. We demonstrated that while tonsillar NK cells, ILC2s, and ILC3s originated from a common CD34-CD117+ ILC precursor pool, final steps of ILC2 development deviated independently and became mutually exclusive from those of NK cells and ILC3s, whose developmental pathways overlapped. Moreover, we identified a CD34-CD117+ ILC precursor population that expressed CD56 and gave rise to NK cells and ILC3s but not to ILC2s. These data support a model of human ILC development distinct from the mouse, whereby human NK cells and ILC3s share a common developmental pathway separate from ILC2s.


Subject(s)
Killer Cells, Natural/immunology , Lymphocytes/immunology , Palatine Tonsil/immunology , Animals , Antigens, CD34/metabolism , CD56 Antigen/metabolism , Cell Differentiation , Cell Lineage , Cells, Cultured , Gene Expression Profiling , Humans , Immunity, Innate , Lymphocyte Activation , Mice , Proto-Oncogene Proteins c-kit/metabolism
16.
Blood ; 132(17): 1792-1804, 2018 10 25.
Article in English | MEDLINE | ID: mdl-30158248

ABSTRACT

Acute myeloid leukemia (AML) can evade the mouse and human innate immune system by suppressing natural killer (NK) cell development and NK cell function. This is driven in part by the overexpression of microRNA (miR)-29b in the NK cells of AML patients, but how this occurs is unknown. In the current study, we demonstrate that the transcription factor aryl hydrocarbon receptor (AHR) directly regulates miR-29b expression. We show that human AML blasts activate the AHR pathway and induce miR-29b expression in NK cells, thereby impairing NK cell maturation and NK cell function, which can be reversed by treating NK cells with an AHR antagonist. Finally, we show that inhibition of constitutive AHR activation in AML blasts lowers their threshold for apoptosis and decreases their resistance to NK cell cytotoxicity. Together, these results identify the AHR pathway as a molecular mechanism by which AML impairs NK cell development and function. The results lay the groundwork in establishing AHR antagonists as potential therapeutic agents for clinical development in the treatment of AML.


Subject(s)
Gene Expression Regulation, Leukemic/genetics , Killer Cells, Natural/immunology , Leukemia, Myeloid, Acute/immunology , MicroRNAs/biosynthesis , Receptors, Aryl Hydrocarbon/metabolism , Animals , Humans , Killer Cells, Natural/cytology , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Mice , Signal Transduction/physiology
17.
Am J Cancer Res ; 8(6): 1083-1089, 2018.
Article in English | MEDLINE | ID: mdl-30034945

ABSTRACT

CAR T cells have shown clinical efficacy for acute lymphoblastic leukemia, but this therapy has not been effective for acute myeloid leukemia (AML), and other treatment options are needed. Theoretically, CAR-NK cells have a more favorable toxicity profile compared to CAR T cells, especially in avoiding adverse effects such as cytokine release syndrome. However, the clinical evidence for this has not yet been reported. In the current study, we tested the safety of CD33-CAR NK cells in patients with relapsed and refractory AML. At doses up to 5 × 109 (5 billion) cells per patient, no significant adverse effects were observed. CAR NK-92 cells can be produced at much lower cost compared to CAR T cells, and we believe after being optimized, they will be widely accessible for the treatment of cancer.

18.
Oncoimmunology ; 7(6): e1431085, 2018.
Article in English | MEDLINE | ID: mdl-29872557

ABSTRACT

Natural products comprise an important class of biologically active molecules. Many of these compounds derived from natural sources exhibit specific physiologic or biochemical effects. An example of a natural product is chitosan, which is enriched in the shells of certain seafood that are frequently consumed worldwide. Like other natural products, chitosan has the potential for applications in clinical medicine and perhaps in cancer therapy. Toward this end, the immunomodulatory or anti-cancer properties of chitosan have yet to be reported. In this study, we discovered that chitosan enhanced the anti-tumor activity of natural killer (NK) cells by activating dendritic cells (DCs). In the presence of DCs, chitosan augmented IFN-γ production by human NK cells. Mechanistically, chitosan activated DCs to express pro-inflammatory cytokines such as interleukin (IL)-12 and IL-15, which in turn activated the STAT4 and NF-κB signaling pathways, respectively, in NK cells. Moreover, chitosan promoted NK cell survival, and also enhanced NK cell cytotoxicity against leukemia cells. Finally, a related in vivo study demonstrated that chitosan activated NK cells against B16F10 tumor cells in an immunocompetent syngeneic murine melanoma model. This effect was accompanied by in vivo upregulation of IL-12 and IL-15 in DCs, as well as increased IFN-γ production and cytolytic degranulation in NK cells. Collectively, our results demonstrate that chitosan activates DCs leading to enhanced capacity for immune surveillance by NK cells. We believe that our study has future clinical applications for chitosan in the prevention or treatment of cancer and infectious diseases.

19.
J Immunol ; 199(7): 2333-2342, 2017 10 01.
Article in English | MEDLINE | ID: mdl-28842466

ABSTRACT

Group 3 innate lymphoid cells (ILC3s) are important regulators of the immune system, maintaining homeostasis in the presence of commensal bacteria, but activating immune defenses in response to microbial pathogens. ILC3s are a robust source of IL-22, a cytokine critical for stimulating the antimicrobial response. We sought to identify cytokines that can promote proliferation and induce or maintain IL-22 production by ILC3s and determine a molecular mechanism for this process. We identified IL-18 as a cytokine that cooperates with an ILC3 survival factor, IL-15, to induce proliferation of human ILC3s, as well as induce and maintain IL-22 production. To determine a mechanism of action, we examined the NF-κB pathway, which is activated by IL-18 signaling. We found that the NF-κB complex signaling component, p65, binds to the proximal region of the IL22 promoter and promotes transcriptional activity. Finally, we observed that CD11c+ dendritic cells expressing IL-18 are found in close proximity to ILC3s in human tonsils in situ. Therefore, we identify a new mechanism by which human ILC3s proliferate and produce IL-22, and identify NF-κB as a potential therapeutic target to be considered in pathologic states characterized by overproduction of IL-18 and/or IL-22.


Subject(s)
Cell Proliferation , Interleukin-18/metabolism , Interleukins/biosynthesis , Lymphocytes/physiology , NF-kappa B/metabolism , Signal Transduction , Dendritic Cells/physiology , Humans , Immunity, Innate , Interleukin-15/immunology , Interleukins/genetics , Interleukins/immunology , Palatine Tonsil/cytology , Palatine Tonsil/immunology , Promoter Regions, Genetic , Signal Transduction/immunology , Transcription Factor RelA/metabolism , Interleukin-22
20.
Tetrahedron ; 69(36): 7706-7712, 2013 Sep 09.
Article in English | MEDLINE | ID: mdl-24058215

ABSTRACT

Ether transfer methodology is capable of stereoselectively generating 1,3-diol mono- and diethers in good yield. Surprisingly, allylic and benzylic substrates provide none of the desired products when exposed to previously optimized conditions of iodine monochloride. Herein, second-generation activation conditions for ether transfer have been developed that circumvents undesired side reactions for these substrates. The application of this chemistry to the enantioselective synthesis of diospongins A and B has now been accomplished.

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