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Introduction: Formative assessments have overall been shown to improve summative evaluations in medical education. However, it remains unclear if utilizing them for course credit in an integrated curriculum over multiple subspecialties is beneficial for student acquisition of knowledge. We set out to determine if grading formative quizzes had an effect on student acquisition of knowledge via summative assessments. Materials and Methods: In 2020, quizzes remained mandatory, but were not graded for course credit. We collected and compared formative (quiz) and summative (unit exam) score data from student cohorts when quizzes were graded versus not graded. Medical college admission test (MCAT) score, gender, and underrepresented in medicine (URM) status data were utilized to determine if they had effects on outcomes. We used a predefined region of indifference (± 5%) and second-generation p-values to determine if there were meaningful differences in average summative exam scores. Results: Despite a drop in quiz scores after removing course credit, differences in average summative exam scores fully resided within the region of indifference for three of five course blocks, indicating no meaningful differences in summative exam scores existed for those blocks. In other blocks, the difference was not fully nested within the region of indifference; however, all data overlapped with this region, implying exam score differences were inconclusive for these blocks. Conclusions: Our study demonstrates that there is either no meaningful effect on summative assessments or no conclusive detrimental effects when mandatory quizzes are not graded for course credit.
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Canine malignant melanoma provides a clinically relevant, large animal parallel patient population to study the GD2-reactive hu14.18-IL-2 immunocytokine as it is similar to human melanoma and expresses GD2. The objectives of this study were to evaluate safety, radiation fractionation, and identify informative biomarkers of an in-situ tumor vaccine involving local radiation therapy plus intratumoral-immunocytokine in melanoma tumor-bearing dogs. Twelve dogs (six dogs/arm) with locally advanced or metastatic melanoma were randomized to receive a single 8â Gy fraction (arm A) or three 8â Gy fractions over 1 week (arm B) to the primary site and regional lymph nodes (when clinically involved) with the single or last fraction 5 days before intratumoral-immunocytokine at 12â mg/m 2 on 3 consecutive days. Serial tumor biopsies were obtained. All 12 dogs completed protocol treatment, and none experienced significant or unexpected adverse events. Evidence of antitumor activity includes one dog with a complete response at day 60, one dog with a partial response at day 60, and four dogs with mixed responses. Histology of serial biopsies shows a variably timed increase in intratumoral lymphocytic inflammation in some dogs. Canine NanoString analyses of serial biopsies identified changes in gene signatures of innate and adaptive cell types versus baseline. There were no significant differences in NanoString results between arm A and arm B. We conclude that intratumoral-immunocytokine in combination with local radiation therapy in canine melanoma is well tolerated and has antitumor activity with the potential to inform clinical development in melanoma patients.
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Enfermedades de los Perros , Interleucina-2 , Melanoma , Perros , Animales , Melanoma/radioterapia , Melanoma/inmunología , Melanoma/patología , Enfermedades de los Perros/radioterapia , Enfermedades de los Perros/inmunología , Neoplasias Cutáneas/radioterapia , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Femenino , MasculinoRESUMEN
Epstein-Barr virus (EBV) is an important cause of human lymphomas, including Burkitt lymphoma (BL). EBV+ BLs are driven by Myc translocation and have stringent forms of viral latency that do not express either of the two major EBV oncoproteins, EBNA2 (which mimics Notch signaling) and LMP1 (which activates NF-κB signaling). Suppression of Myc-induced apoptosis, often through mutation of the TP53 (p53) gene or inhibition of pro-apoptotic BCL2L11 (BIM) gene expression, is required for development of Myc-driven BLs. EBV+ BLs contain fewer cellular mutations in apoptotic pathways compared to EBV-negative BLs, suggesting that latent EBV infection inhibits Myc-induced apoptosis. Here we use an EBNA2-deleted EBV virus (ΔEBNA2 EBV) to create the first in vivo model for EBV+ BL-like lymphomas derived from primary human B cells. We show that cord blood B cells infected with both ΔEBNA2 EBV and a Myc-expressing vector proliferate indefinitely on a CD40L/IL21 expressing feeder layer in vitro and cause rapid onset EBV+ BL-like tumors in NSG mice. These LMP1/EBNA2-negative Myc-driven lymphomas have wild type p53 and very low BIM, and express numerous germinal center B cell proteins (including TCF3, BACH2, Myb, CD10, CCDN3, and GCSAM) in the absence of BCL6 expression. Myc-induced activation of Myb mediates expression of many of these BL-associated proteins. We demonstrate that Myc blocks LMP1 expression both by inhibiting expression of cellular factors (STAT3 and Src) that activate LMP1 transcription and by increasing expression of proteins (DNMT3B and UHRF1) known to enhance DNA methylation of the LMP1 promoters in human BLs. These results show that latent EBV infection collaborates with Myc over-expression to induce BL-like human B-cell lymphomas in mice. As NF-κB signaling retards the growth of EBV-negative BLs, Myc-mediated repression of LMP1 may be essential for latent EBV infection and Myc translocation to collaboratively induce human BLs.
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Linfocitos B , Linfoma de Burkitt , Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Proteínas Proto-Oncogénicas c-myc , Latencia del Virus , Animales , Linfoma de Burkitt/virología , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patología , Linfoma de Burkitt/genética , Humanos , Ratones , Infecciones por Virus de Epstein-Barr/virología , Infecciones por Virus de Epstein-Barr/metabolismo , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Herpesvirus Humano 4/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Linfocitos B/virología , Linfocitos B/metabolismo , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Antígenos Nucleares del Virus de Epstein-Barr/genética , Apoptosis , Proteínas Virales/metabolismo , Proteínas Virales/genéticaRESUMEN
The ability to locally deliver bioactive molecules to distinct regions of the skeleton may provide a novel means by which to improve fracture healing, treat neoplasms or infections, or modulate growth. In this study, we constructed single-sided mineral-coated poly-ε-caprolactone membranes capable of binding and releasing transforming growth factor beta 1 (TGF-ß1) and human growth hormone (hGH). After demonstrating biological activity in vitro and characterization of their release, these thin bioabsorbable membranes were surgically implanted using an immature rabbit model. Membranes were circumferentially wrapped under the periosteum, thus placed in direct contact with the proximal metaphysis to assess its bioactivity in vivo. The direct effects on the metaphyseal bone, bone marrow, and overlying periosteum were assessed using radiography and histology. Effects of membrane placement at the tibial growth plate were assessed via physeal heights, tibial growth rates (pulsed fluorochrome labeling), and tibial lengths. Subperiosteal placement of the mineralized membranes induced greater local chondrogenesis in the plain mineral and TGF-ß1 samples than the hGH. More exuberant and circumferential ossification was seen in the TGF-ß1 treated tibiae. The TGF-ß1 membranes also induced hypocellularity of the bone marrow with characteristics of gelatinous degeneration not seen in the other groups. While the proximal tibial growth plates were taller in the hGH treated than TGF-ß1, no differences in growth rates or overall tibial lengths were found. In conclusion, these data demonstrate the feasibility of using bioabsorbable mineral coated membranes to deliver biologically active compounds subperiosteally in a sustained fashion to affect cells at the insertion site, bone marrow, and even growth plate.
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Hormona de Crecimiento Humana , Periostio , Poliésteres , Factor de Crecimiento Transformador beta1 , Animales , Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/farmacología , Poliésteres/química , Humanos , Conejos , Factor de Crecimiento Transformador beta1/farmacología , Periostio/efectos de los fármacos , Membranas Artificiales , Tibia/efectos de los fármacosRESUMEN
We previously demonstrated that a subset of acute myeloid leukemia (AML) patients with concurrent RAS pathway and TP53 mutations have an extremely poor prognosis and that most of these TP53 mutations are missense mutations. Here, we report that, in contrast to the mixed AML and T cell malignancy that developed in NrasG12D/+ p53-/- (NP-/-) mice, NrasG12D/+ p53R172H/+ (NPmut) mice rapidly developed inflammation-associated AML. Under the inflammatory conditions, NPmut hematopoietic stem and progenitor cells (HSPCs) displayed imbalanced myelopoiesis and lymphopoiesis and mostly normal cell proliferation despite MEK/ERK hyperactivation. RNA-Seq analysis revealed that oncogenic NRAS signaling and mutant p53 synergized to establish an NPmut-AML transcriptome distinct from that of NP-/- cells. The NPmut-AML transcriptome showed GATA2 downregulation and elevated the expression of inflammatory genes, including those linked to NF-κB signaling. NF-κB was also upregulated in human NRAS TP53 AML. Exogenous expression of GATA2 in human NPmut KY821 AML cells downregulated inflammatory gene expression. Mouse and human NPmut AML cells were sensitive to MEK and NF-κB inhibition in vitro. The proteasome inhibitor bortezomib stabilized the NF-κB-inhibitory protein IκBα, reduced inflammatory gene expression, and potentiated the survival benefit of a MEK inhibitor in NPmut mice. Our study demonstrates that a p53 structural mutant synergized with oncogenic NRAS to promote AML through mechanisms distinct from p53 loss.
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Leucemia Mieloide Aguda , FN-kappa B , Proteína p53 Supresora de Tumor , Animales , Humanos , Ratones , Mutación con Ganancia de Función , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos , Mutación , FN-kappa B/metabolismo , Proteína p53 Supresora de Tumor/genéticaRESUMEN
The highly utilized KC model has a reported lethality rate of about 30%, which has been attributed to pancreas cancer. However, a competing cause of lethality in KC mice is due to the activation of mutant-Kras gene (KrasG12D/+) in the multipotent progenitor cells (MPP), and subsequent development of Kras-mutant T-cell acute lymphoblastic leukemia (T-ALL). Overall, 20% (5/25) of KC mice developed T-ALL by 9 months of age. Transplantation of pooled bone marrow from KC mice into CD45 congenic mice caused T-ALL in 100% of recipient mice, confirming that mutant-Kras expression in the hematologic compartment is driving the development of T-ALL in the KC mouse model. These results are an essential consideration for investigators using this model. Further, the lower penetrance of T-ALL in KC mice (versus existing leukemia models) suggests this model could be considered as an alternative research model to evaluate onset and factors that exacerbate the development of T-ALL.
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Neoplasias Pancreáticas , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Animales , Ratones , Ratones Transgénicos , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismoRESUMEN
Systemic Epstein-Barr virus (EBV)-positive T-cell lymphoma of childhood (SETLC) is a rare, rapidly progressive, and often fatal disease of children and young adults characterized by monoclonal expansion of EBV-positive T cells in tissues or peripheral blood following infection with EBV. Its distinction from other EBV-positive T-cell lymphoproliferative disorders with overlapping features can be difficult, and particular diagnostic features may not be manifest until autopsy examination. We present the case of a 10-year-old boy with significant disability due to remote traumatic brain injury following non-accidental head trauma who died unexpectedly at home. Given the history of physical abuse and the potential for homicide charges, significant medicolegal implications arose with this case. Pathologic investigation ultimately revealed conclusive diagnostic features of SETLC including extensive proliferation of EBV-positive T cells in multiple organs. A natural manner of death was confirmed, thereby excluding delayed homicide related to complications of non-accidental head trauma.
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Péptidos y Proteínas de Señalización Intracelular , Leucemia , Proteínas de Unión al GTP Monoméricas , Fosfoproteínas , Células Precursoras de Linfocitos T , Animales , GTP Fosfohidrolasas , Haploinsuficiencia/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Leucemia/genética , Proteínas de la Membrana , Ratones , Proteínas de Unión al GTP Monoméricas/genética , Mutación , Proteínas Nucleares , Fosfoproteínas/genéticaRESUMEN
Mammalian GATA2 gene encodes a dual zinc finger transcription factor, which is essential for hematopoietic stem cell (HSC) generation in the aorta, gonad, mesonephros (AGM) region, HSC self-renewal, and specification of progenitor cell fates. Previously, we demonstrated that Gata2 expression in AGM is controlled by its intronic +9.5 enhancer. Gata2 +9.5 deficiency removes the E-box motif and the GATA site and depletes fetal liver HSCs. However, whether this enhancer has an essential role in regulating adult hematopoiesis has not been established. Here, we evaluate Gata2 +9.5 enhancer function in adult hematopoiesis. +9.5+/- bone marrow cells displayed reduced T cell reconstitution in a competitive transplant assay. Donor-derived analysis demonstrated a previously unrecognized function of the +9.5 enhancer in T cell development at the lymphoid-primed multipotent progenitor stage. Moreover, +9.5+/- adult HSCs displayed increased apoptosis and reduced long-term self-renewal capability in comparison with wild-type (WT) HSCs. These phenotypes were more moderate than those of Gata2+/- HSCs. Consistent with the phenotypic characterization, Gata2 expression in +9.5+/- LSKs was moderately higher than that in Gata2+/- LSKs, but lower than that in WT LSKs. Our data suggest that +9.5 deficiency compromises, without completely abrogating, Gata2 expression in adult HSCs.
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Hematopoyesis , Mesonefro , Animales , Diferenciación Celular/genética , Autorrenovación de las Células/genética , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , MamíferosRESUMEN
Mutations in chromatin regulator ASXL1 are frequently identified in myeloid malignancies, in particular â¼40% of patients with chronic myelomonocytic leukemia (CMML). ASXL1 mutations are associated with poor prognosis in CMML and significantly co-occur with NRAS mutations. Here, we show that concurrent ASXL1 and NRAS mutations defined a population of CMML patients who had shorter leukemia-free survival than those with ASXL1 mutation only. Corroborating this human data, Asxl1-/- accelerated CMML progression and promoted CMML transformation to acute myeloid leukemia (AML) in NrasG12D/+ mice. NrasG12D/+;Asxl1-/- (NA) leukemia cells displayed hyperactivation of MEK/ERK signaling, increased global levels of H3K27ac, upregulation of Flt3. Moreover, we find that NA-AML cells overexpressed all the major inhibitory immune checkpoint ligands: programmed death-ligand 1 (PD-L1)/PD-L2, CD155, and CD80/CD86. Among them, overexpression of PD-L1 and CD86 correlated with upregulation of AP-1 transcription factors (TFs) in NA-AML cells. An AP-1 inhibitor or short hairpin RNAs against AP-1 TF Jun decreased PD-L1 and CD86 expression in NA-AML cells. Once NA-AML cells were transplanted into syngeneic recipients, NA-derived T cells were not detectable. Host-derived wild-type T cells overexpressed programmed cell death protein 1 (PD-1) and T-cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) receptors, leading to a predominant exhausted T-cell phenotype. Combined inhibition of MEK and BET resulted in downregulation of Flt3 and AP-1 expression, partial restoration of the immune microenvironment, enhancement of CD8 T-cell cytotoxicity, and prolonged survival in NA-AML mice. Our study suggests that combined targeted therapy and immunotherapy may be beneficial for treating secondary AML with concurrent ASXL1 and NRAS mutations.
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Modelos Animales de Enfermedad , GTP Fosfohidrolasas/genética , Leucemia Mieloide Aguda/patología , Leucemia Mielomonocítica Crónica/patología , Proteínas de la Membrana/genética , Mutación , Proteínas Represoras/genética , Microambiente Tumoral , Animales , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/inmunología , Leucemia Mielomonocítica Crónica/genética , Leucemia Mielomonocítica Crónica/inmunología , Ratones , Proteínas de Unión al GTP Monoméricas/genética , Fenotipo , Transducción de SeñalRESUMEN
Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is an aggressive subtype of T-cell ALL. Although genetic mutations hyperactivating cytokine receptor/Ras signaling are prevalent in ETP-ALL, it remains unknown how activated Ras signaling contributes to ETP-ALL. Here, we find that in addition to the frequent oncogenic RAS mutations, wild-type (WT) KRAS transcript level was significantly downregulated in human ETP-ALL cells. Similarly, loss of WT Kras in NrasQ61R/+ mice promoted hyperactivation of extracellular signal-regulated kinase (ERK) signaling, thymocyte hyperproliferation, and expansion of the ETP compartment. Kras-/-; NrasQ61R/+ mice developed early onset of T-cell malignancy that recapitulates many biological and molecular features of human ETP-ALL. Mechanistically, RNA-sequencing analysis and quantitative proteomics study identified that Rasgrp1, a Ras guanine nucleotide exchange factor, was greatly downregulated in mouse and human ETP-ALL. Unexpectedly, hyperactivated Nras/ERK signaling suppressed Rasgrp1 expression and reduced Rasgrp1 level led to increased ERK signaling, thereby establishing a positive feedback loop to augment Nras/ERK signaling and promote cell proliferation. Corroborating our cell line data, Rasgrp1 haploinsufficiency induced Rasgrp1 downregulation and increased phosphorylated ERK level and ETP expansion in NrasQ61R/+ mice. Our study identifies Rasgrp1 as a negative regulator of Ras/ERK signaling in oncogenic Nras-driven ETP-like leukemia.
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Regulación hacia Abajo , Regulación Leucémica de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido , Proteínas de Unión al GTP Monoméricas , Mutación Missense , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteínas Proto-Oncogénicas p21(ras)/deficiencia , Sustitución de Aminoácidos , Animales , Proliferación Celular/genética , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas/genética , Ratones , Ratones Noqueados , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Proteínas Proto-Oncogénicas p21(ras)/metabolismoRESUMEN
NRAS Q61 mutations are prevalent in advanced/relapsed multiple myeloma (MM) and correlate with poor patient outcomes. Thus, we generated a novel MM model by conditionally activating expression of endogenous NrasQ61R and an MYC transgene in germinal center (GC) B cells (VQ mice). VQ mice developed a highly malignant MM characterized by a high proliferation index, hyperactivation of extracellular signal-regulated kinase and AKT signaling, impaired hematopoiesis, widespread extramedullary disease, bone lesions, kidney abnormalities, preserved programmed cell death protein 1 and T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain immune-checkpoint pathways, and expression of human high-risk MM gene signatures. VQ MM mice recapitulate most of the biological and clinical features of human advanced/high-risk MM. These MM phenotypes are serially transplantable in syngeneic recipients. Two MM cell lines were also derived to facilitate future genetic manipulations. Combination therapies based on MEK inhibition significantly prolonged the survival of VQ mice with advanced-stage MM. Our study provides a strong rationale to develop MEK inhibition-based therapies for treating advanced/relapsed MM.
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Linfocitos B/patología , Modelos Animales de Enfermedad , Proteínas de Unión al GTP Monoméricas/genética , Mieloma Múltiple/genética , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Centro Germinal/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mieloma Múltiple/patología , TransgenesAsunto(s)
Elementos de Facilitación Genéticos , Factor de Transcripción GATA2/fisiología , Regulación Neoplásica de la Expresión Génica , Células Madre Hematopoyéticas/citología , Leucemia Experimental/patología , Animales , Factor de Transcripción GATA2/genética , Células Madre Hematopoyéticas/metabolismo , Leucemia Experimental/genética , Leucemia Experimental/metabolismo , Ratones , Ratones NoqueadosRESUMEN
Numerous recurrent genetic mutations are known to occur in acute myeloid leukemia (AML). Among these common mutations, Fms-like tyrosine kinase 3 remains as one of the most frequently mutated genes in AML. We observed apparent marrow expansion of megakaryocytes in three out of six patients with Flt3-mutated AML following treatment with a recently FDA-approved Flt3 inhibitor, gilteritinib which possesses activity against internal tandem duplication and tyrosine kinase domain Flt3 mutations and also inhibits tyrosine kinase AXL. To assess whether biopsy findings can be attributed to promotion of megakaryocytic (Mk) differentiation with gilteritinib, we devised a cellular assay by overexpressing double mutated Flt3-ITDY591F/Y919F in chronic myeloid leukemia cell line K562 to study Mk differentiation in the presence of Flt3 and AXL inhibitors with non-mutually exclusive mechanisms. These experiments demonstrated the lack of direct effect Flt3 inhibitors gilteritinib and quizartinib on megakaryocytic differentiation at either transcriptional or phenotypic levels, and highlighted antileukemic effects of AXL receptor tyrosine kinase inhibitor and its potential role in megakaryocytic development.
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Eosinophilic disorders and related syndromes represent a heterogeneous group of neoplastic and nonneoplastic conditions, characterized by more eosinophils in the peripheral blood, and may involve eosinophil-induced organ damage. In the WHO classification of myeloid and lymphoid neoplasms, eosinophilic disorders characterized by dysregulated tyrosine kinase (TK) fusion genes are recognized as a new category termed, myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1 or with PCM1-JAK2. In addition to these aforementioned TK fusion genes, rearrangements involving FLT3 and ABL1 genes have also been described. These new NCCN Guidelines include recommendations for the diagnosis, staging, and treatment of any one of the myeloid/lymphoid neoplasms with eosinophilia (MLN-Eo) and a TK fusion gene included in the 2017 WHO Classification, as well as MLN-Eo and a FLT3 or ABL1 rearrangement.
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Eosinofilia , Trastornos Mieloproliferativos , Neoplasias , Eosinofilia/diagnóstico , Eosinofilia/genética , Humanos , Trastornos Mieloproliferativos/diagnóstico , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/terapia , Proteínas de Fusión Oncogénica/genéticaRESUMEN
Stem and progenitor cell fate transitions constitute key decision points in organismal development that enable access to a developmental path or actively preclude others. Using the hematopoietic system, we analyzed the relative importance of cell fate-promoting mechanisms versus negating fate-suppressing mechanisms to engineer progenitor cells with multilineage differentiation potential. Deletion of the murine Gata2-77 enhancer, with a human equivalent that causes leukemia, downregulates the transcription factor GATA2 and blocks progenitor differentiation into erythrocytes, megakaryocytes, basophils, and granulocytes, but not macrophages. Using multiomics and single-cell analyses, we demonstrated that the enhancer orchestrates a balance between pro- and anti-fate circuitry in single cells. By increasing GATA2 expression, the enhancer instigates a fate-promoting mechanism while abrogating an innate immunity-linked, fate-suppressing mechanism. During embryogenesis, the suppressing mechanism dominated in enhancer mutant progenitors, thus yielding progenitors with a predominant monocytic differentiation potential. Coordinating fate-promoting and -suppressing circuits therefore averts deconstruction of a multifate system into a monopotent system and maintains critical progenitor heterogeneity and functionality.
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Diferenciación Celular/genética , Factor de Transcripción GATA2/genética , Eliminación de Gen , Mutación de Línea Germinal , Células Madre/fisiología , Adolescente , Adulto , Animales , Basófilos/fisiología , Células Cultivadas , Elementos de Facilitación Genéticos/genética , Eritrocitos/fisiología , Femenino , Hematopoyesis/genética , Humanos , Macrófagos/fisiología , Megacariocitos/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Análisis de la Célula IndividualRESUMEN
EBV transforms B cells in vitro and causes human B-cell lymphomas including classical Hodgkin lymphoma (CHL), Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL). The EBV latency protein, EBNA2, transcriptionally activates the promoters of all latent viral protein-coding genes expressed in type III EBV latency and is essential for EBV's ability to transform B cells in vitro. However, EBNA2 is not expressed in EBV-infected CHLs and BLs in humans. EBV-positive CHLs have type II latency and are largely driven by the EBV LMP1/LMP2A proteins, while EBV-positive BLs, which usually have type I latency are largely driven by c-Myc translocations, and only express the EBNA1 protein and viral non-coding RNAs. Approximately 15% of human BLs contain naturally occurring EBNA2-deleted viruses that support a form of viral latency known as Wp-restricted (expressing the EBNA-LP, EBNA3A/3B/3C, EBNA1 and BHRF1 proteins), but whether Wp-restricted latency and/or EBNA2-deleted EBV can induce lymphomas in humanized mice, or in the absence of c-Myc translocations, is unknown. Here we show that a naturally occurring EBNA2-deleted EBV strain (P3HR1) isolated from a human BL induces EBV-positive B-cell lymphomas in a subset of infected cord blood-humanized (CBH) mice. Furthermore, we find that P3HR1-infected lymphoma cells support two different viral latency types and phenotypes that are mutually exclusive: 1) Large (often multinucleated), CD30-positive, CD45-negative cells reminiscent of the Reed-Sternberg (RS) cells in CHL that express high levels of LMP1 but not EBNA-LP (consistent with type II viral latency); and 2) smaller monomorphic CD30-negative DLBCL-like cells that express EBNA-LP and EBNA3A but not LMP1 (consistent with Wp-restricted latency). These results reveal that EBNA2 is not absolutely required for EBV to form tumors in CBH mice and suggest that P3HR1 virus can be used to model EBV positive lymphomas with both Wp-restricted and type II latency in vivo.
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Infecciones por Virus de Epstein-Barr , Antígenos Nucleares del Virus de Epstein-Barr/genética , Eliminación de Gen , Herpesvirus Humano 4/fisiología , Enfermedad de Hodgkin , Linfoma de Células B Grandes Difuso , Proteínas Virales/genética , Latencia del Virus , Animales , Línea Celular , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/metabolismo , Infecciones por Virus de Epstein-Barr/patología , Infecciones por Virus de Epstein-Barr/virología , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Herpesvirus Humano 4/patogenicidad , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/metabolismo , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/virología , Humanos , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/virología , Ratones , Proteínas Virales/metabolismoRESUMEN
PURPOSE: We sought to improve upon frontline bendamustine/rituximab (BR) induction therapy followed by rituximab maintenance in untreated high-risk follicular lymphoma (FL). PATIENTS AND METHODS: Patients were randomized to BR induction followed by 2-year rituximab maintenance (BR-R), BR with bortezomib and rituximab maintenance (BVR-R), or BR followed by lenalidomide (1 year) with rituximab maintenance (BR-LR). Dual primary objectives were complete remission (CR) rate and 1-year disease-free survival (DFS); 289 patients enrolled (NCT01216683). RESULTS: For induction, 92%, 87%, and 86% of patients randomized to BR-R, BVR-R, or BR-LR received six cycles, respectively. CR rate with BR versus BVR induction was 62% versus 75%, respectively (P = 0.04). One-year DFS rates with BR-R versus BR-LR were 85% versus 67%, respectively (P = 0.0009). This was due to an imbalance in CR rates post-BR induction and discontinuation due to adverse events (AEs). The most common grade 3-4 AEs for BVR versus BR were neutropenia and sensory neuropathy (12% vs <1%); 83% of the latter occurred with intravenous bortezomib. The most common grade 3-4 AEs related to LR versus rituximab maintenance were neutropenia 66% versus 21%, respectively (P < 0.0001), and febrile neutropenia 10% versus 2%, respectively (P = 0.05). The overall treatment-related mortality was 1.4%. With 5-year median follow-up, 3-year PFS rates for BR-R, BVR-R, and BR-LR were 77%, 82%, and 76%, respectively (P = 0.36) with OS rates of 87%, 90%, and 84%, respectively (P = 0.79). For prognostication, CR rate and POD-24 were associated with survival. CONCLUSIONS: Altogether, neither bortezomib added to BR induction nor lenalidomide added to rituximab maintenance immediately post-BR induction is recommended in untreated FL.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma Folicular/tratamiento farmacológico , Recurrencia Local de Neoplasia/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Clorhidrato de Bendamustina/administración & dosificación , Clorhidrato de Bendamustina/efectos adversos , Bortezomib/administración & dosificación , Bortezomib/efectos adversos , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Humanos , Infusiones Intravenosas , Lenalidomida/administración & dosificación , Lenalidomida/efectos adversos , Linfoma Folicular/mortalidad , Quimioterapia de Mantención/efectos adversos , Quimioterapia de Mantención/métodos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Supervivencia sin Progresión , Inducción de Remisión/métodos , Rituximab/administración & dosificación , Rituximab/efectos adversos , Adulto JovenRESUMEN
PURPOSE: We analyzed whole transcriptome sequencing in tumors from 23 patients with stage III or IV melanoma from a pilot trial of the anti-GD2 immunocytokine, hu14.18-IL2, to identify predictive immune and/or tumor biomarkers in patients with melanoma at high risk for recurrence. EXPERIMENTAL DESIGN: Patients were randomly assigned to receive the first of three monthly courses of hu14.18-IL2 immunotherapy either before (Group A) or after (Group B) complete surgical resection of all known diseases. Tumors were evaluated by histology and whole transcriptome sequencing. RESULTS: Tumor-infiltrating lymphocyte (TIL) levels directly associated with relapse-free survival (RFS) and overall survival (OS) in resected tumors from Group A, where early responses to the immunotherapy agent could be assessed. TIL levels directly associated with a previously reported immune signature, which associated with RFS and OS, particularly in Group A tumors. In Group A tumors, there were decreased cell-cycling gene RNA transcripts, but increased RNA transcripts for repair and growth genes. We found that outcome (RFS and OS) was directly associated with several immune signatures and immune-related RNA transcripts and inversely associated with several tumor growth-associated transcripts, particularly in Group A tumors. Most of these associations were not seen in Group B tumors. CONCLUSIONS: We interpret these data to signify that both immunologic and tumoral cell processes, as measured by RNA-sequencing analyses detected shortly after initiation of hu14.18-IL2 therapy, are associated with long-term survival and could potentially be used as prognostic biomarkers in tumor resection specimens obtained after initiating neoadjuvant immunotherapy.