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1.
Nat Commun ; 11(1): 1459, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32193378

RESUMO

Combined PARP and immune checkpoint inhibition has yielded encouraging results in ovarian cancer, but predictive biomarkers are lacking. We performed immunogenomic profiling and highly multiplexed single-cell imaging on tumor samples from patients enrolled in a Phase I/II trial of niraparib and pembrolizumab in ovarian cancer (NCT02657889). We identify two determinants of response; mutational signature 3 reflecting defective homologous recombination DNA repair, and positive immune score as a surrogate of interferon-primed exhausted CD8 + T-cells in the tumor microenvironment. Presence of one or both features associates with an improved outcome while concurrent absence yields no responses. Single-cell spatial analysis reveals prominent interactions of exhausted CD8 + T-cells and PD-L1 + macrophages and PD-L1 + tumor cells as mechanistic determinants of response. Furthermore, spatial analysis of two extreme responders shows differential clustering of exhausted CD8 + T-cells with PD-L1 + macrophages in the first, and exhausted CD8 + T-cells with cancer cells harboring genomic PD-L1 and PD-L2 amplification in the second.

2.
Mod Pathol ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051557

RESUMO

Ancillary testing during the initial workup of acute myeloid leukemia (AML) is largely performed using aspirated materials. We utilized multiplex immunofluorescence (MIF) imaging with digital image analysis to perform an in situ analysis of the microenvironment in NPM1-mutated AML using diagnostic bone marrow biopsy tissues (N = 17) and correlated these findings with diagnostic next-generation sequencing (NGS, N = 17), flow cytometry (FC, N = 14), and first remission (CR1) NPM1-specific molecular MRD (n = 16) data. The total CD3-positive T-cell percentages correlated positively between FC and MIF (r = 0.53, p = 0.05), but were significantly lower by MIF (1.62% vs. 3.4%, p = 0.009). The percentage of mutant NPM1-positive (NPM1c+) cells ranged from 9.7 to 90.8% (median 45.4%) and did not correlate with the NPM1 mutant allele fraction by NGS (p > 0.05). The percentage of CD34+/NPM1c+ cells ranged from 0 to 1.8% (median 0.07%). The percentage of NPM1c+ cells correlated inversely (34% vs. 62%, p = 0.03), while the percentages of CD3-/NPM1c- cells (64% vs. 35%, p = 0.03), and specifically CD3-/CD4-/NPM1c- cells (26% vs. 13%, p = 0.04), correlated positively with subsequent MRD. Discordances between MIF and FC/NGS data suggest that aspirate materials are likely an imperfect reflection of the core biopsy tissue. Furthermore, increased numbers of NPM1 wild-type cells within the microenvironment at diagnosis correlate with the subsequent presence of MRD.

3.
Blood Adv ; 4(1): 122-126, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31917843

RESUMO

Disease relapse remains the leading cause of failure after autologous stem cell transplantation (ASCT) for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). We conducted a phase 2, multicenter, single-arm study of the anti-PD-1 monoclonal antibody pembrolizumab given after ASCT in patients with chemosensitive DLBCL, hypothesizing that it would improve the progression-free survival (PFS) at 18 months after ASCT (primary endpoint) from 60% to 80%. Pembrolizumab was administered at 200 mg IV every 3 weeks for up to 8 cycles, starting within 21 days of post-ASCT discharge. Twenty-nine patients were treated on this study; 62% completed all 8 cycles. Seventy-nine percent of patients experienced at least one grade 3 or higher adverse event, and 34% experienced at least one grade 2 or higher immune-related adverse event. Overall, 59% of patients were alive and progression free at 18 months, which did not meet the primary endpoint. The 18-month overall survival was 93%. In conclusion, pembrolizumab was successfully administered as post-ASCT consolidation in patients with R/R DLBCL, but the PFS did not meet the protocol-specific primary objective and therefore does not support a larger confirmatory study. This trial was registered at www.clinicaltrials.gov as #NCT02362997.

4.
Methods Mol Biol ; 2055: 455-465, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31502165

RESUMO

The rapidly evolving fields of precision medicine and immuno-oncology are together driving an increasing need for detailed investigation of the tumor immune microenvironment (TIME) in a variety of solid tumors and hematologic neoplasms. The development of targeted therapies that may be efficacious in reprogramming the host immune response to recognize and eliminate tumor cells requires accurate identification of the various inflammatory cells and the spatial relationships between them within the TIME. While currently established techniques enable diagnostic pathologists to routinely interrogate for up to two protein markers and evaluate their expression by visual examination, there is a growing need to reliably query many more targets (i.e., multiplexing) simultaneously in a given tissue specimen, in order to more precisely characterize and distinguish the TIMEs between different tumor types, and between patients. Several technologies aimed at achieving these goals, including multiplex colorimetric immunohistochemistry (mCIHC), multiplex immunofluorescence (mIF), cyclic immunofluorescence (CycIF), multiplexed ion beam imaging (MIBI), codetection by indexing (CODEX), and digital spatial profiling (DSP), are discussed.

5.
Blood Adv ; 3(23): 4065-4080, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31816062

RESUMO

Classical Hodgkin lymphoma (cHL) is composed of rare malignant Hodgkin Reed-Sternberg (HRS) cells within an extensive, but ineffective, inflammatory/immune cell infiltrate. HRS cells exhibit near-universal somatic copy gains of chromosome 9p/9p24.1, which increase expression of the programmed cell death protein 1 (PD-1) ligands. To define genetic mechanisms of response and resistance to PD-1 blockade and identify complementary treatment targets, we performed whole-exome sequencing of flow cytometry-sorted HRS cells from 23 excisional biopsies of newly diagnosed cHLs, including 8 Epstein-Barr virus-positive (EBV+) tumors. We identified significantly mutated cancer candidate genes (CCGs) as well as somatic copy number alterations and structural variations and characterized their contribution to disease-defining immune evasion mechanisms and nuclear factor κB (NF-κB), JAK/STAT, and PI3K signaling pathways. EBV- cHLs had a higher prevalence of genetic alterations in the NF-κB and major histocompatibility complex class I antigen presentation pathways. In this young cHL cohort (median age, 26 years), we identified a predominant mutational signature of spontaneous deamination of cytosine- phosphate-guanines ("Aging"), in addition to apolipoprotein B mRNA editing catalytic polypeptide-like, activation-induced cytidine deaminase, and microsatellite instability (MSI)-associated hypermutation. In particular, the mutational burden in EBV- cHLs was among the highest reported, similar to that of carcinogen-induced tumors. Together, the overall high mutational burden, MSI-associated hypermutation, and newly identified genetic alterations represent additional potential bases for the efficacy of PD-1 blockade in cHL. Of note, recurrent cHL alterations, including B2M, TNFAIP3, STAT6, GNA13, and XPO1 mutations and 2p/2p15, 6p21.32, 6q23.3, and 9p/9p24.1 copy number alterations, were also identified in >20% of primary mediastinal B-cell lymphomas, highlighting shared pathogenetic mechanisms in these diseases.

6.
Blood ; 134(23): 2059-2069, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31697809

RESUMO

Classic Hodgkin lymphoma (cHL) is a tumor composed of rare, atypical, germinal center-derived B cells (Hodgkin Reed-Sternberg [HRS] cells) embedded within a robust but ineffective inflammatory milieu. The cHL tumor microenvironment (TME) is compartmentalized into "niches" rich in programmed cell death-1 ligand (PD-L1)-positive HRS cells and tumor-associated macrophages (TAMs), which associate with PD-1-positive T cells to suppress antitumor immunity via PD-L1/PD-1 signaling. Despite the exquisite sensitivity of cHL to PD-1 checkpoint blockade, most patients eventually relapse and need therapeutic alternatives. Using multiplex immunofluorescence microscopy with digital image analysis, we found that cHL is highly enriched for non-T-regulatory, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4)-positive T cells (compared with reactive lymphoid tissues) that outnumber PD-1-positive and lymphocyte-activating gene-3 (LAG-3)-positive T cells. In addition, T cells touching HRS cells are more frequently positive for CTLA-4 than for PD-1 or LAG-3. We further found that HRS cells, and a subset of TAMs, are positive for the CTLA-4 ligand CD86 and that the fractions of T cells and TAMs that are CTLA-4-positive and CD86-positive, respectively, are greater within a 75 µm HRS cell niche relative to areas outside this region (CTLA-4, 38% vs 18% [P = .0001]; CD86, 38% vs 24% [P = .0007]). Importantly, CTLA-4-positive cells are present, and focally contact HRS cells, in recurrent cHL tumors following a variety of therapies, including PD-1 blockade. These results implicate CTLA-4:CD86 interactions as a component of the immunologically privileged niche surrounding HRS cells and raise the possibility that patients with cHL refractory to PD-1 blockade may benefit from CTLA-4 blockade.

7.
Blood ; 134(26): 2369-2382, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31697821

RESUMO

Primary mediastinal large B-cell lymphomas (PMBLs) are aggressive tumors that typically present as large mediastinal masses in young women. PMBLs share clinical, transcriptional, and molecular features with classical Hodgkin lymphoma (cHL), including constitutive activation of nuclear factor κB (NF-κB), JAK/STAT signaling, and programmed cell death protein 1 (PD-1)-mediated immune evasion. The demonstrated efficacy of PD-1 blockade in relapsed/refractory PMBLs led to recent approval by the US Food and Drug Administration and underscored the importance of characterizing targetable genetic vulnerabilities in this disease. Here, we report a comprehensive analysis of recurrent genetic alterations -somatic mutations, somatic copy number alterations, and structural variants-in a cohort of 37 newly diagnosed PMBLs. We identified a median of 9 genetic drivers per PMBL, including known and newly identified components of the JAK/STAT and NF-κB signaling pathways and frequent B2M alterations that limit major histocompatibility complex class I expression, as in cHL. PMBL also exhibited frequent, newly identified driver mutations in ZNF217 and an additional epigenetic modifier, EZH2. The majority of these alterations were clonal, which supports their role as early drivers. In PMBL, we identified several previously uncharacterized molecular features that may increase sensitivity to PD-1 blockade, including high tumor mutational burden, microsatellite instability, and an apolipoprotein B mRNA editing catalytic polypeptide-like (APOBEC) mutational signature. The shared genetic features between PMBL and cHL provide a framework for analyzing the mechanism of action of PD-1 blockade in these related lymphoid malignancies.

8.
J Clin Oncol ; 37(34): 3291-3299, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31609651

RESUMO

PURPOSE: Patients with relapsed or refractory primary mediastinal large B-cell lymphoma (rrPMBCL) have a poor prognosis, and their treatment represents an urgent and unmet need. Because PMBCL is associated with genetic aberrations at 9p24 and overexpression of programmed cell death-1 (PD-1) ligands (PD-L1), it is hypothesized to be susceptible to PD-1 blockade. METHODS: In the phase IB KEYNOTE-013 (ClinicalTrials.gov identifier: NCT01953692) and phase II KEYNOTE-170 (ClinicalTrials.gov identifier: NCT02576990) studies, adults with rrPMBCL received pembrolizumab for up to 2 years or until disease progression or unacceptable toxicity. The primary end points were safety and objective response rate in KEYNOTE-013 and objective response rate in KEYNOTE-170. Secondary end points included duration of response, progression-free survival, overall survival, and safety. Exploratory end points included association between biomarkers and pembrolizumab activity. RESULTS: The objective response rate was 48% (7 complete responses; 33%) among 21 patients in KEYNOTE-013 and 45% (7 complete responses; 13%) among 53 patients in KEYNOTE-170. After a median follow-up time of 29.1 months in KEYNOTE-013 and 12.5 months in KEYNOTE-170, the median duration of response was not reached in either study. No patient with complete response experienced progression, including 2 patients with complete response for at least 1 year off therapy. Treatment-related adverse events occurred in 24% of patients in KEYNOTE-013 and 23% of patients in KEYNOTE-170. There were no treatment-related deaths. Among 42 evaluable patients, the magnitude of the 9p24 gene abnormality was associated with PD-L1 expression, which was itself significantly associated with progression-free survival. CONCLUSION: Pembrolizumab is associated with high response rate, durable activity, and a manageable safety profile in patients with rrPMBCL.

10.
Haematologica ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31471373

RESUMO

B-cell receptor signaling pathway components represent promising treatment targets in multiple B-cell malignancies including diffuse large B-cell lymphoma. In in vitro and in vivo model systems, a subset of diffuse large B-cell lymphomas depend upon B-cell receptor survival signals and respond to proximal B-cell receptor/phosphoinositide 3 kinase blockade. However, single-agent B-cell receptor pathway inhibitors have had more limited activity in patients with diffuse large B-cell lymphoma, underscoring the need for indicators of sensitivity to B-cell receptor blockade and insights into potential resistance mechanisms. Here, we report highly significant transcriptional upregulation of C-X-C chemokine receptor 4 in B-cell receptor-dependent diffuse large B-cell lymphoma cell lines and primary tumors following chemical spleen tyrosine kinase inhibition, molecular spleen tyrosine kinase depletion or chemical phosphoinositide 3 kinase blockade. Spleen tyrosine kinase or phosphoinositide 3 kinase inhibition also selectively upregulated cell surface C-X-C chemokine receptor 4 protein expression in B-cell receptor-dependent diffuse large B-cell lymphomas. C-X-C chemokine receptor 4 expression was directly modulated by forkhead box O1 via the phosphoinositide 3 kinase/protein kinase B/forkhead box O1 signaling axis. Following chemical spleen tyrosine kinase inhibition, all B-cell receptor-dependent diffuse large B-cell lymphomas exhibited significantly increased stromal cell-derived factor alpha induced chemotaxis, consistent with the role of C-X-C chemokine receptor 4 signaling in B-cell migration. Select phosphoinositide 3 kinase isoform inhibitors also augmented stromal cell-derived factor alpha induced chemotaxis. These data define C-X-C chemokine receptor 4 upregulation as an indicator of sensitivity to B-cell receptor/phosphoinositide 3 kinase blockade and identify C-X-C chemokine receptor 4 signaling as a potential resistance mechanism in B-cell receptor-dependent diffuse large B-cell lymphomas.

11.
Cold Spring Harb Protoc ; 2019(7): pdb.prot099754, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262962

RESUMO

Colloidal gold particles bind tightly but not covalently to proteins at pH values that are around the protein's pI. Colloidal gold particles conjugated with a wide range of anti-immunoglobulin antibodies, Protein A, or streptavidin are available commercially. Gold labels were developed originally for electron microscopic studies, but they also work well at the level of the light microscope. They give higher resolution than enzyme-based methods and avoid the problems of substrate preparation and endogenous enzyme activity. Until recently, the gold labels lacked sensitivity at the level of light microscopy, but the recent development of the photochemical silver method of amplification, described here, has overcome this problem. Unamplified gold labels can be detected under the light microscope using bright-field illumination in which the label ranges from pale pink to deep red, depending on the strength of the reaction. Nomarski differential interference contrast microscopy makes the label appear dark red to black. With the silver enhancement method, the gold particles become coated in metallic silver and yield a black-brown label, best visualized by bright-field optics. Gold labeling methods are compatible with many histochemical stains. Gold labeling reactions are very readily controlled, because the appearance of staining can be monitored directly and continuously under the microscope.

12.
Cold Spring Harb Protoc ; 2019(7): pdb.prot099762, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262963

RESUMO

The binding of radiolabeled reagents to cells is detected by coating the specimen with a photographic emulsion. When the emulsion is developed, silver grains can be seen at the location of the radiolabel. The silver grains appear as black dots in bright-field microscopy but are most readily detected by dark-field illumination, in which they are seen as intense silver reflections on a black background. The detection of iodine-labeled reagents is extremely sensitive, and the reaction is readily controlled by setting up duplicate samples and varying the exposure time. The method is compatible with histological stains and can be used in double-labeling procedures with enzyme- or fluorochrome-labeled reagents. When iodine-labeled and enzyme-labeled reagents are used together for double labeling, the enzyme-labeled reagents must be developed before the photographic emulsion is added.

13.
Cancer Immunol Res ; 7(8): 1230-1236, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31217164

RESUMO

Immunotherapy with checkpoint inhibitors, such as the programmed death-1 (PD-1) antibodies pembrolizumab and nivolumab, are effective in a variety of tumors, yet not all patients respond. Tumor microsatellite instability-high (MSI-H) has emerged as a biomarker of response to checkpoint blockade, leading to the tissue agnostic approval of pembrolizumab in MSI-H cancers. Here we describe a patient with MSI-H colorectal cancer that was treated with this immune checkpoint inhibitor and exhibited progression of disease. We examined this intrinsic resistance through genomic, transcriptional, and pathologic characterization of the patient's tumor and the associated immune microenvironment. The tumor had typical MSI-H molecular features, including a high neoantigen load. We also identified biallelic loss of the gene for ß2-microglobulin (B2M), whose product is critical for antigen presentation. Immune infiltration deconvolution analysis of bulk transcriptome data from this anti-PD-1-resistant tumor and hundreds of other colorectal cancer specimens revealed a high natural killer cell and M2 macrophage infiltration in the patient's cancer. This was confirmed by single-cell transcriptome analysis and multiplex immunofluorescence. Our study provides insight into resistance in MSI-H tumors and suggests immunotherapeutic strategies in additional genomic contexts of colorectal cancer.

14.
Sci Transl Med ; 11(497)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217338

RESUMO

The activated B cell (ABC-like) subtype of diffuse large B cell lymphoma (DLBCL) is characterized by chronic activation of signaling initiated by immunoglobulin µ (IgM). By analyzing the DNA copy number profiles of 1000 DLBCL tumors, we identified gains of 18q21.2 as the most frequent genetic alteration in ABC-like DLBCL. Using integrative analysis of matched gene expression profiling data, we found that the TCF4 (E2-2) transcription factor gene was the target of these alterations. Overexpression of TCF4 in ABC-like DLBCL cell lines led to its occupancy on immunoglobulin (IGHM) and MYC gene enhancers and increased expression of these genes at the transcript and protein levels. Inhibition of TCF4 activity with dominant-negative constructs was synthetically lethal to ABC-like DLBCL cell lines harboring TCF4 DNA copy gains, highlighting these gains as an attractive potential therapeutic target. Furthermore, the TCF4 gene was one of the top BRD4-regulated genes in DLBCL cell lines. BET proteolysis-targeting chimera (PROTAC) ARV771 extinguished TCF4, MYC, and IgM expression and killed ABC-like DLBCL cells in vitro. In DLBCL xenograft models, ARV771 treatment reduced tumor growth and prolonged survival. This work highlights a genetic mechanism for promoting immunoglobulin signaling in ABC-like DLBCL and provides a functional rationale for the use of BET inhibitors in this disease.

15.
Cancer Cell ; 35(6): 885-900.e10, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185212

RESUMO

We investigated the role of chemokines in regulating T cell accumulation in solid tumors. CCL5 and CXCL9 overexpression was associated with CD8+ T cell infiltration in solid tumors. T cell infiltration required tumor cell-derived CCL5 and was amplified by IFN-γ-inducible, myeloid cell-secreted CXCL9. CCL5 and CXCL9 coexpression revealed immunoreactive tumors with prolonged survival and response to checkpoint blockade. Loss of CCL5 expression in human tumors was associated with epigenetic silencing through DNA methylation. Reduction of CCL5 expression caused tumor-infiltrating lymphocyte (TIL) desertification, whereas forced CCL5 expression prevented Cxcl9 expression and TILs loss, and attenuated tumor growth in mice through IFN-γ. The cooperation between tumor-derived CCL5 and IFN-γ-inducible CXCR3 ligands secreted by myeloid cells is key for orchestrating T cell infiltration in immunoreactive and immunoresponsive tumors.

16.
Oncologist ; 24(8): 1013-1021, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31088979

RESUMO

Safe use of immune checkpoint blockade in patients with cancer and autoimmune disorders requires a better understanding of the pathophysiology of immunologic activation. We describe the immune correlates of reactivation of granulomatosis with polyangiitis (GPA)-an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis-in a patient with metastatic urothelial carcinoma treated with pembrolizumab. After PD-1 blockade, an inflammatory pulmonary nodule demonstrated a granulomatous, CD4+ T-cell infiltrate, correlating with increased CD4+ and CD8+ naïve memory cells in the peripheral blood without changes in other immune checkpoint receptors. Placed within the context of the existing literature on GPA and disease control, our findings suggest a key role for PD-1 in GPA self-tolerance and that selective strategies for immunotherapy may be needed in patients with certain autoimmune disorders. We further summarize the current literature regarding reactivation of autoimmune disorders in patients undergoing immune checkpoint blockade, as well as potential immunosuppressive strategies to minimize the risks of further vasculitic reactivation upon rechallenge with anti-PD-1 blockade. KEY POINTS: Nonspecific imaging findings in patients with cancer and rheumatological disorders may require biopsy to distinguish underlying pathology.Patients with rheumatologic disorders have increased risk of reactivation with PD-(L)1 immune checkpoint blockade, requiring assessment of disease status before starting treatment.Further study is needed to evaluate the efficacy of treatment regimens in preventing and controlling disease reactivation.

17.
Clin Cancer Res ; 25(15): 4644-4655, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31061067

RESUMO

PURPOSE: Hormone receptor-positive/HER2-negative (HR+/HER2-) breast cancer is associated with low levels of stromal tumor-infiltrating lymphocytes (sTIL) and PD-L1, and demonstrates poor responses to checkpoint inhibitor therapy. Evaluating the effect of standard chemotherapy on the immune microenvironment may suggest new opportunities for immunotherapy-based approaches to treating HR+/HER2- breast tumors. EXPERIMENTAL DESIGN: HR+/HER2- breast tumors were analyzed before and after neoadjuvant chemotherapy. sTIL were assessed histologically; CD8+ cells, CD68+ cells, and PD-L1 staining were assessed immunohistochemically; whole transcriptome sequencing and panel RNA expression analysis (NanoString) were performed. RESULTS: Ninety-six patients were analyzed from two cohorts (n = 55, Dana-Farber cohort; n = 41, MD Anderson cohort). sTIL, CD8, and PD-L1 on tumor cells were higher in tumors with basal PAM50 intrinsic subtype. Higher levels of tissue-based lymphocyte (sTIL, CD8, PD-L1) and macrophage (CD68) markers, as well as gene expression markers of lymphocyte or macrophage phenotypes (NanoString or CIBERSORT), correlated with favorable response to neoadjuvant chemotherapy, but not with improved distant metastasis-free survival in these cohorts or a large gene expression dataset (N = 302). In paired pre-/postchemotherapy samples, sTIL and CD8+ cells were significantly decreased after treatment, whereas expression analyses (NanoString) demonstrated significant increase of multiple myeloid signatures. Single gene expression implicated increased expression of immunosuppressive (M2-like) macrophage-specific genes after chemotherapy. CONCLUSIONS: The immune microenvironment of HR+/HER2- tumors differs according to tumor biology. This cohort of paired pre-/postchemotherapy samples suggests a critical role for immunosuppressive macrophage expansion in residual disease. The role of macrophages in chemoresistance should be explored, and further evaluation of macrophage-targeting therapy is warranted.

18.
Dis Model Mech ; 12(5)2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064769

RESUMO

Somatic loss-of-function mutations of the additional sex combs-like transcriptional regulator 1 (ASXL1) gene are common genetic abnormalities in human myeloid malignancies and induce clonal expansion of mutated hematopoietic stem cells (HSCs). To understand how ASXL1 disruption leads to myeloid cell transformation, we generated asxl1 haploinsufficient and null zebrafish lines using genome-editing technology. Here, we show that homozygous loss of asxl1 leads to apoptosis of newly formed HSCs. Apoptosis occurred via the mitochondrial apoptotic pathway mediated by upregulation of bim and bid Half of the asxl1+/ - zebrafish had myeloproliferative neoplasms (MPNs) by 5 months of age. Heterozygous loss of asxl1 combined with heterozygous loss of tet2 led to a more penetrant MPN phenotype, while heterozygous loss of asxl1 combined with complete loss of tet2 led to acute myeloid leukemia (AML). These findings support the use of asxl1+/ - zebrafish as a strategy to identify small-molecule drugs to suppress the growth of asxl1 mutant but not wild-type HSCs in individuals with somatically acquired inactivating mutations of ASXL1.


Assuntos
Neoplasias da Medula Óssea/patologia , Mutação/genética , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Apoptose , Sequência de Bases , Sobrevivência Celular , Embrião não Mamífero/metabolismo , Edição de Genes , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/patologia , Organogênese , Regulação para Cima/genética , Peixe-Zebra/embriologia
19.
J Clin Oncol ; 37(23): 1997-2007, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31112476

RESUMO

PURPOSE: Nivolumab, an anti-programmed death-1 monoclonal antibody, has demonstrated frequent and durable responses in relapsed/refractory classic Hodgkin lymphoma (cHL). We report results from Cohort D of the CheckMate 205 trial, which assessed nivolumab monotherapy followed by nivolumab plus doxorubicin, vinblastine, and dacarbazine (N-AVD) for newly diagnosed cHL. METHODS: Patients 18 years of age or older with untreated, advanced-stage (defined as III to IV and IIB with unfavorable risk factors) cHL were eligible for Cohort D of this multicenter, noncomparative, phase II trial. Patients received nivolumab monotherapy for four doses, followed by 12 doses of N-AVD; all doses were every 2 weeks, and nivolumab was administered at 240 mg intravenously. The primary end point was safety. Efficacy end points included objective response rate and modified progression-free survival, defined as time to disease progression/relapse, death, or next therapy. Chromosome 9p24.1 alterations and programmed death-ligand 1 expression were assessed in Hodgkin Reed-Sternberg cells in evaluable patients. RESULTS: A total of 51 patients were enrolled and treated. At diagnosis, 49% of patients had an International Prognostic Score of 3 or greater. Overall, 59% experienced a grade 3 to 4 treatment-related adverse event. Treatment-related febrile neutropenia was reported in 10% of patients. Endocrine immune-mediated adverse events were all grade 1 to 2 and did not require high-dose corticosteroids; all nonendocrine immune-mediated adverse events resolved (most commonly, rash; 5.9%). At the end of therapy, the objective response rate (95% CI) per independent radiology review committee was 84% (71% to 93%), with 67% (52% to 79%), achieving complete remission (five patients [10%] were nonevaluable and counted as nonresponders). With a minimum follow-up of 9.4 months, 9-month modified progression-free survival was 92%. Patients with higher-level Hodgkin Reed-Sternberg programmed death-ligand 1 expression had more favorable responses to N-AVD (P = .041). CONCLUSION: Nivolumab followed by N-AVD was associated with promising efficacy and safety profiles for newly diagnosed, advanced-stage cHL.

20.
Blood ; 134(1): 22-29, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-30952672

RESUMO

Autologous stem cell transplantation (ASCT) remains the standard of care for patients with relapsed/refractory (RR) classical Hodgkin lymphoma (cHL) who respond to salvage chemotherapy. However, relapse after ASCT remains a frequent cause of treatment failure, with poor subsequent prognosis. Because cHL is uniquely vulnerable to programmed cell death-1 (PD-1) blockade, PD-1 blockade given as consolidation after ASCT could improve ASCT outcomes. We therefore conducted a multicohort phase 2 study of pembrolizumab in patients with RR cHL after ASCT, hypothesizing that it would improve the progression-free survival (PFS) at 18 months after ASCT (primary end point) from 60% to 80%. Pembrolizumab was administered at 200 mg IV every 3 weeks for up to 8 cycles, starting within 21 days of post-ASCT discharge. Thirty patients were treated on this study. The median age was 33 years, and 90% were high-risk by clinical criteria. Seventy-seven percent completed all 8 cycles. Toxicity was manageable, with 30% of patients experiencing at least 1 grade 3 or higher adverse event (AE), and 40% at least 1 grade 2 or higher immune-related AE. Two patients were lost to follow-up in complete remission at 12 months. The PFS at 18 months for the 28 evaluable patients was 82%, meeting the primary end point. The 18-month overall survival was 100%. In conclusion, pembrolizumab was successfully administered as post-ASCT consolidation in patients with RR cHL, and resulted in a promising PFS in a high-risk patient cohort, supporting the testing of this strategy in a randomized trial. This trial was registered at www.clinicaltrials.gov as #NCT02362997.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adulto , Idoso , Quimioterapia de Consolidação/métodos , Intervalo Livre de Doença , Feminino , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/mortalidade , Doença de Hodgkin/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/imunologia , Terapia de Salvação/métodos , Transplante Autólogo
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