Prediction of outcomes for high-count monoclonal B lymphocytosis using an epigenetic and immunogenetic signature

ABSTRACT

Monoclonal B-cell lymphocytosis (MBL) progresses to chronic lymphocytic leukemia (CLL) requiring therapy at 1% to 5% per year. Improved prediction of progression would greatly benefit individuals with MBL. Patients with CLL separate into 3 distinct epigenetic subtypes (epitypes) with high prognostic significance, and recently the intermediate epitype has been shown to be enriched for high-risk immunoglobulin lambda variable (IGLV) 3-21 rearrangements, impacting outcomes for these patients. Here, we employed this combined strategy to generate the epigenetic and light chain immunoglobulin (ELCLV3-21) signature to classify 219 individuals with MBL. The ELCLV3-21 high-risk signature distinguished MBL individuals with a high probability of progression (39.9% and 71.1% at 5 and 10 years, respectively). ELCLV3-21 improved the accuracy of predicting time to therapy for individuals with MBL compared with other established prognostic indicators, including the CLL international prognostic index (c-statistic, 0.767 vs 0.668, respectively). Comparing ELCLV3-21 risk groups in MBL vs a cohort of 226 patients with CLL revealed ELCLV3-21 high-risk individuals with MBL had significantly shorter time to therapy (P = .003) and reduced overall survival (P = .03) compared with ELCLV3-21 low-risk individuals with CLL. These results highlight the power of the ELCLV3-21 approach to identify individuals with a higher likelihood of adverse clinical outcome and may provide a more accurate approach to classify individuals with small B-cell clones.

Early Stereotactic Body Radiotherapy to the Primary Lung Lesion for Patients with Advanced NSCLC Treated with First-Line Systemic Therapy

PURPOSE/OBJECTIVE(S)

Although adding consolidative stereotactic body radiotherapy (SBRT) to systemic therapy improves survival in advanced non-small cell lung cancer (NSCLC), the optimal timing of SBRT remains unclear. This study aimed to explore the clinical outcome of early and delayed SBRT to primary lung lesions of advanced NSCLC patients treated with first-line systemic therapy.

MATERIALS/METHODS

We identified patients with advanced NSCLC who were suitable to receiveSBRT for the primary lung tumors after first-line systemic therapy. All eligible patients were treated with first-line systemic therapy and SBRT for their primary lung lesions. Early SBRT group was defined as patients who received SBRT for their primary lung tumor at the maximal response of systemic therapy. Delayed SBRT group was defined as patients who received SBRT after the occurrence of oligoprogression in primary lung tumor. The primary endpoints were progression-free survival 1 (PFS1, time from start of first-line systemic therapy to disease progression) and PFS2 (time from start of first-line systemic therapy to disease progression after SBRT). Overall survival (OS) and adverse effects (AEs) were secondary endpoints. A two-sided P value of 0.05 was considered statistically significant. All of the statistical analyses were performed with statistical software.

RESULTS

A total of184 patients with advanced NSCLC treated with SBRT for primary tumors were screened, and 49 patients were eligible for enrollment in this study. The median age of the entire cohort was 66 years (range, 37-80 years), and 34 (69.4%) patients were male. Thirty-four patients (69.4%) were treated by target therapy and 15 (30.6%) were treated by chemotherapy and immunotherapy. Of the 49 eligible patients, 28(57.1%) received early SBRT to lung primary tumor and 21(42.9%) received delayed SBRT to lung primary tumor. The early SBRT group showed a significantly prolonged PFS1 as compared with the delayed SBRT group (mPFS1: 30 months vs. 8 months, P<0.001). The median PFS2 of the early SBRT group was longer than that of the delayed SBRT group, but the difference between the two groups did not achieve a statistical significance (mPFS2: 42 months vs. 23 months, P = 0.303). Median OS of both groups has not reached. No severe toxicities (≥grade 3) were observed in early SBRT group and only one patient in the delayed SBRT group experienced grade 3 radiation pneumonitis.

CONCLUSION

Early SBRT to the primary lung lesion significantly improved PFS and is a new potentially effective and tolerable treatment option for patients with advanced NSCLC who had stable disease during first-line systemic therapy.

[Associations of all-cause mortality with admission blood pressure variability during multiple hospitalizations in acute decompensated heart failure]

Objective: To investigate whether admission blood pressure (BP) variability during multiple hospitalizations is associated with all-cause mortality independent of baseline BP in acute decompensated heart failure (ADHF). Methods: Patients with ADHF admitted to the Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University from September 2013 to December 2017 were retrospectively enrolled. The risk of all-cause mortality associated with indices of BP variability, including mean admission BPs, standard deviation of BP and coefficient of variation of BP during multiple hospitalizations was assessed, using Cox regression model. Results: A total of 1 006 ADHF patients (mean aged (69.3±13.5) years; 411 (40.8%) female; 670 (66.6%) with preserved ejection fraction) were enrolled. During a median follow-up of 1.54 years, 47.0% of patients died. In all ADHF patients, after adjusting for confounding factors, for every 1-standard deviation (SD) increase in SD and coefficient of variation (CV) of systolic BP, the risk of all-cause mortality increased by 10% and 11%, respectively (SD: HR, 1.10, 95%CI, 1.01-1.21, P=0.029, CV: HR, 1.11, 95%CI, 1.02-1.21, P=0.017); for every 1-SD increase in the mean of diastolic BP, the risk of all cause mortality decreased by 25% (HR, 0.75; 95%CI, 0.65-0.87; P<0.001). In ADHF patients with preserved ejection fraction, after accounted for potential confounders, higher SD and CV of admitted systolic and diastolic BP were significantly associated with higher risk of all-cause mortality, regardless of whether confounding factors were adjusted (P≤0.049); After adjusting for confounding factors, the risk of all-cause mortality increased by 18% and 19% for every 1-SD increase in SD and CV of systolic BP, while the risk of all-cause mortality increased by 11% and 15% for every 1-SD increase in SD and CV of diastolic BP. In ADHF patients with reduced ejection fraction, after adjusting for confounding factors, the higher the mean admission systolic BP during multiple hospitalizations, the lower the risk of total mortality (HR, 0.68; 95%CI, 0.47-1.00; P=0.049). Conclusions: In patients with ADHF, independent of baseline BP, BP variability during multiple hospitalizations was strong predictor of all-cause mortality.

Coherent Picture on the Pure Spin Transport between Ag/Bi and Ferromagnets

In a joint effort of both experiments and first-principles calculations, we resolve a hotly debated controversy and provide a coherent picture on the pure spin transport between Ag/Bi and ferromagnets. We demonstrate a strong inverse Rashba-Edelstein effect (IREE) at the interface in between Ag/Bi with a ferromagnetic metal (FM) but not with a ferromagnetic insulator. This is in sharp contrast to the previously claimed IREE at Ag/Bi interface or inverse spin Hall effect dominated spin transport. A more than one order of magnitude modulation of IREE signal is realized for different Ag/Bi-FM interfaces, casting strong tunability and a new direction for searching efficient spintronics materials.

[Efficacy and safety of carotid endarterectomy combined with endovascular therapy in hybrid operating room for patients with segmental atherosclerotic internal carotid artery occlusion]

The current study aimed to investigate the efficacy and safety of carotid endarterectomy combined with endovascular therapy in hybrid operating room for patients with segmental atherosclerotic internal carotid artery occlusion, and share the experience of preoperative screening of patients suitable for vascular reconstruction. A total of 20 patients with internal carotid artery occlusion (ICAO) who were admitted to the Department of Neurosurgery, General Hospital of Tianjin Medical University from May 2018 to May 2020 were collected, and 15 patients met the inclusion criteria. All patients received hybrid surgery. The total success rate of recanalization was 14/15, and only 1 patient developed ICA re-occlusion at 1 year follow up.Therefore, carotid endarterectomy combined with endovascular treatment in hybrid operating room was an alternative treatment for patients with segmental atherosclerotic internal carotid artery occlusion.

Identification and targeting of the developmental blockade in extranodal natural killer/T cell lymphoma

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.

[Investigation and analysis of a mass ammonia gas poisoning accident]

Objective: To investigation and analysis of ammonia gas leakage in a meat factory. Methods: In April 2013, Enterprise managers and workers were investigated, and clinical data of 24 patients were analyzed. Results: The company caused a leak in the ammonia pipeline maintenance operation, Among the patients, 20 had stimulus response and 4 had mild poisoning. Conclusion: To prevent group occupational ammonia poisoning, it is necessary to strengthen the awareness of occupational disease prevention of enterprise owners and the awareness of self-protection of workers.

DNA methylation epitypes highlight underlying developmental and disease pathways in acute myeloid leukemia

Acute myeloid leukemia (AML) is a molecularly complex disease characterized by heterogeneous tumor genetic profiles and involving numerous pathogenic mechanisms and pathways. Integration of molecular data types across multiple patient cohorts may advance current genetic approaches for improved subclassification and understanding of the biology of the disease. Here, we analyzed genome-wide DNA methylation in 649 AML patients using Illumina arrays and identified a configuration of 13 subtypes (termed “epitypes”) using unbiased clustering. Integration of genetic data revealed that most epitypes were associated with a certain recurrent mutation (or combination) in a majority of patients, yet other epitypes were largely independent. Epitypes showed developmental blockage at discrete stages of myeloid differentiation, revealing epitypes that retain arrested hematopoietic stem-cell-like phenotypes. Detailed analyses of DNA methylation patterns identified unique patterns of aberrant hyper- and hypomethylation among epitypes, with variable involvement of transcription factors influencing promoter, enhancer, and repressed regions. Patients in epitypes with stem-cell-like methylation features showed inferior overall survival along with up-regulated stem cell gene expression signatures. We further identified a DNA methylation signature involving STAT motifs associated with FLT3-ITD mutations. Finally, DNA methylation signatures were stable at relapse for the large majority of patients, and rare epitype switching accompanied loss of the dominant epitype mutations and reversion to stem-cell-like methylation patterns. These results show that DNA methylation-based classification integrates important molecular features of AML to reveal the diverse pathogenic and biological aspects of the disease.

Magnetic Hamiltonian parameter estimation using deep learning techniques

Understanding spin textures in magnetic systems is extremely important to the spintronics and it is vital to extrapolate the magnetic Hamiltonian parameters through the experimentally determined spin. It can provide a better complementary link between theories and experimental results. We demonstrate deep learning can quantify the magnetic Hamiltonian from magnetic domain images. To train the deep neural network, we generated domain configurations with Monte Carlo method. The errors from the estimations was analyzed with statistical methods and confirmed the network was successfully trained to relate the Hamiltonian parameters with magnetic structure characteristics. The network was applied to estimate experimentally observed domain images. The results are consistent with the reported results, which verifies the effectiveness of our methods. On the basis of our study, we anticipate that the deep learning techniques make a bridge to connect the experimental and theoretical approaches not only in magnetism but also throughout any scientific research.

Creation of skyrmions in van der Waals ferromagnet Fe3GeTe2 on (Co/Pd) n superlattice

Magnetic skyrmions are topological spin textures, which usually exist in noncentrosymmetric materials where the crystal inversion symmetry breaking generates the so-called Dzyaloshinskii-Moriya interaction. This requirement unfortunately excludes many important magnetic material classes, including the recently found two-dimensional van der Waals (vdW) magnetic materials, which offer unprecedented opportunities for spintronic technology. Using photoemission electron microscopy and Lorentz transmission electron microscopy, we investigated and stabilized Néel-type magnetic skyrmion in vdW ferromagnetic Fe₃GeTe₂ on top of (Co/Pd) _n in which the Fe₃GeTe₂ has a centrosymmetric crystal structure. We demonstrate that the magnetic coupling between the Fe₃GeTe₂ and the (Co/Pd) _n could create skyrmions in Fe₃GeTe₂ without the need of an external magnetic field. Our results open exciting opportunities in spintronic research and the engineering of topologically protected nanoscale features by expanding the group of skyrmion host materials to include these previously unknown vdW magnets.

[Comparison of heart failure and COVID-19 in chest CT features and clinical characteristics]

Objective: To identify the characteristics including clinical features and pulmonary computed tomography (CT) features of heart failure and COVID-19. Methods: This study was a retrospective study. A total of 7 patients with heart failure and 12 patients with COVID-19 in the Second Xiangya Hospital of Central South University between December 1, 2019 and February 15, 2020 were enrolled. The baseline clinical and imaging features of the two groups were statistically analyzed. Results: There was no significant difference in age and sex between the two groups(both P>0.05), but the incidence of epidemiological contact history, fever or respiratory symptoms in the COVID-19 group was significantly higher than that in the heart failure group (12/12 vs. 0, P<0.001; 12/12 vs. 4/7, P=0.013). While the proportion of cardiovascular diseases and impaired cardiac function was significantly less than that of the heart failure group(2/12 vs.7/7, P<0.001；0 vs.7/7, P<0.001). For imaging features, both groups had ground-glass opacity and thickening of interlobular septum, but the ratio of central and gradient distribution was higher in patients with heart failure than that in patients with COVID-19 (4/7 vs. 1/12, P=0.04). In heart failure group, the ratio of the expansion of pulmonary veins was also higher (3/7 vs. 0，P=0.013), and the lung lesions can be significantly improved after effective anti-heart failure treatment. Besides, there were more cases with rounded morphology in COVID-19 group（9/12 vs. 2/7, P=0.048）. Conclusions: More patients with COVID-19 have epidemiological history and fever or respiratory symptoms. There are significant differences in chest CT features, such as enlargement of pulmonary veins, lesions distribution and morphology between heart failure and COVID-19.

Intrinsic Mechanism for Anisotropic Magnetoresistance and Experimental Confirmation in Co_{x}Fe_{1-x} Single-Crystal Films

Using first-principles transport calculations, we predict that the anisotropic magnetoresistance (AMR) of single-crystal Co_{x}Fe_{1-x} alloys is strongly dependent on the current orientation and alloy concentration. An intrinsic mechanism for AMR is found to arise from the band crossing due to magnetization-dependent symmetry protection. These special k points can be shifted towards or away from the Fermi energy by varying the alloy composition and hence the exchange splitting, thus allowing AMR tunability. The prediction is confirmed by delicate transport measurements, which further reveal a reciprocal relationship of the longitudinal and transverse resistivities along different crystal axes.

Fast and deterministic switching of a vortex core induced by an out-of-plane current in notch disks

The magnetic vortex, as one of the most interesting magnetic solitons, has attracted great interest over the past two decades. A fast and reliable method to switch vortex polarity and chirality is one of the key issues for various applications. Based on micromagnetic simulation, here we report a fast, low energy cost and deterministic switching of a vortex core, by the designing of a notch structure in disks and the use of out-of-plane current geometry. We demonstrate that with such a design, the multiple switching problems found in notch disk systems can be avoided. Furthermore, the switching time can be reduced by more than 50% compared with disks without notches.

[Mechanism of transcriptional regulation of Meox1 by transforming growth factor β (1) and its effect on cell migration of adult human dermal fibroblasts]

Objective: To explore the transcriptional regulation mechanism of transforming growth factor β(1) (TGF-β(1)) on Meox1 and its effect on cell migration of adult human dermal fibroblasts (HDF-a). Methods: (1) HDF-a cells were cultured in RPMI 1640 complete medium (hereinafter referred to as routinely cultured). The cells were divided into TGF-β(1) stimulation group and blank control group. The cells in TGF-β(1) stimulation group were stimulated with 10 μL TGF-β(1) in the mass concentration of 1 mg/μL, while the cells in blank control group were stimulated with the equal volume of phosphate buffer solution. After 72 hours in culture, partial cells in both groups were collected for transcriptome sequencing. The genes with differential expression ratio greater than or equal to 2 and P<0.01 between the two groups were selected to perform enrichment analysis and analysis of metabolic pathways of the Kyoto Gene and Genome Encyclopedia with, and the expression value of Meox1 per million transcripts (TPM) was recorded (n=3). Partial cells from the two groups were used to detect the Meox1 mRNA expression by real-time fluorescent quantitative reverse transcription polymerase chain reaction (RT-PCR) (n=3). (2) Cultured HDF-a cells in the logarithmic growth phase (the same growth phase of cells below) were divided into empty plasmid group, Smad2 overexpression (OE) group, Smad3 OE group, and Smad4 OE group, which were transfected respectively with 2 μg empty pcDNA3.1 plasmid and pcDNA3.1 plasmids separately carrying Smad2, Smad3, and Smad4 for 6 hours, and then were routinely cultured for 48 hours. The Meox1 mRNA expression in the transfected cells of each group was detected by real-time fluorescent quantitative RT-PCR (n=3). (3) HDF-a cells were routinely cultured and grouped the same as in experiment (1). After 72 hours in culture, the enrichment of Smad2, Smad3, and Smad4 protein on the Meox1 promoter in the cells of each group was detected by chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) (n=3). (4) HDF-a cells were routinely cultured and divided into negative interference group, small interference RNA (siRNA)-Smad2 group, siRNA-Smad3 group, siRNA-Smad4 group, empty plasmid group, Smad2 OE group, Smad3 OE group, and Smad4 OE group, which were transfected respectively with 50 μmol/L random siRNA, siRNA-Smad2, siRNA-Smad3, siRNA-Smad4, 2 μg empty pcDNA3.1 plasmid and pcDNA3.1 plasmids separately carrying Smad2, Smad3, and Smad4 for 6 hours and then routinely cultured for 48 hours. The enrichment of Smad2, Smad3, and Smad4 protein on the Meox1 promoter in the cells of corresponding group was detected by ChIP-qPCR (n=3). (5) Two batches of HDF-a cells were cultured and divided into negative interference group, siRNA-Meox1 group, empty plasmid group, and Meox1 OE group, which were transfected respectively with 50 μmol/L random siRNA, siRNA-Meox1, 2 μg empty pcDNA3.1 plasmid and pcDNA3.1 plasmid carrying Meox1 for 6 hours and then routinely cultured for 24 hours. One batch of cells were subjected to scratch test with the scratch width being observed 24 hours after scratching and compared with the initial width for scratch wound healing; the other batch of cells were subjected to Transwell assay, in which the migrated cells were counted after being routinely cultured for 24 hours (n=3). (6) From January 2018 to June 2019, 3 hypertrophic scar patients (2 males and 1 female, aged 35-56 years) were admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) 8-12 months after burns. The scar tissue and normal skin tissue along the scar margin resected during surgery were taken, and immunohistochemical staining was performed to observe the distribution of Meox1 protein expression. Data were statistically analyzed with one-way analysis of variance and independent sample t test. Results: (1) After 72 hours in culture, a total of 843 genes were obviously differentially expressed between the two groups, being related to tissue repair, cell migration, inflammatory cell chemotaxis induction process and potential signaling pathways such as tumor necrosis factor, interleukin 17, extracellular matrix receptor. The TPM value of Meox1 in the cells of blank control group was 45.9±1.9, which was significantly lower than 163.1±29.5 of TGF-β(1) stimulation group (t=6.88, P<0.01) with RNA-sequencing. After 72 hours in culture, the Meox1 mRNA expression levels in the cells of blank control group was 1.00±0.21, which was significantly lower than 11.00±3.61 of TGF-β(1) stimulation group (t=4.79, P<0.01). (2) After 48 hours in culture, the Meox1 mRNA expression levels in the cells of Smad2 OE group, Smad3 OE group, and Smad4 OE group were 198.70±11.02, 35.47±4.30, 20.27±2.50, respectively, which were significantly higher than 1.03±0.19 of empty plasmid group (t=31.07, 13.80, 13.12, P<0.01). (3) After 72 hours in culture, the enrichment of Smad2, Smad3, and Smad4 protein on the promoter of Meox1 in the cells of TGF-β(1) stimulation group was significantly higher than that of blank control group respectively (t=12.99, 41.47, 29.10, P<0.01). (4) After 48 hours in culture, the enrichment of Smad2 protein on the promoter of Meox1 in the cells of negative interference group was (0.200 000±0.030 000)%, significantly higher than (0.000 770±0.000 013)% of siRNA-Smad2 group (t=11.67, P<0.01); the enrichment of Smad2 protein on the promoter of Meox1 in the cells of empty plasmid group was (0.200 000±0.040 000)%, significantly lower than (0.700 000±0.090 000)% of Smad2 OE group (t=8.85, P<0.01). The enrichment of Smad3 protein on the promoter of Meox1 in the cells of negative interference group was (0.500 0±0.041 3)%, significantly higher than (0.006 0±0.001 3)% of siRNA-Smad3 group (t=17.79, P<0.01); the enrichment of Smad3 protein on the promoter of Meox1 in the cells of empty plasmid group was (0.470 0±0.080 0)%, which was significantly lower than (1.100 0±0.070 0)% of Smad3 OE group (t=9.93, P<0.01). The enrichment of Smad4 protein on the promoter of Meox1 in the cells of negative interference group was similar to that of siRNA-Smad4 group (t=2.11, P>0.05); the enrichment of Smad4 protein on the promoter of Meox1 in the cells of empty plasmid group was similar to that of Smad4 OE group (t=0.60, P>0.05). (5) Twenty-four hours after scratching, the scratch healing width of cells in siRNA-Meox1 group was narrower than that of negative interference group, while that of Meox1 OE group was wider than that of empty plasmid group. After 24 hours in culture, the number of migration cells in negative interference group was significantly higher than that in siRNA-Meox1 group (t=9.12, P<0.01), and that in empty plasmid group was significantly lower than that in Meox1 OE group (t=8.99, P<0.01). (6) The expression of Meox1 protein in the scar tissue was significantly higher than that in normal skin of patients with hypertrophic scars. Conclusions: TGF-β(1) transcriptionally regulates Meox1 expression via Smad2/3 in HDF-a cells, thus promoting cell migration.

Abstract LB-102: Extranodal natural killer/T cell lymphoma (ENKTL) exhibits an unprecedented degree of global DNA hypermethylation, providing a potent targeted therapy in vivo

Extranodal natural killer/T cell lymphoma (ENKTL) is a rare aggressive form of non-Hodgkin lymphoma that is uniformly EBV-positive. Despite the implementation of combinatorial chemotherapies, almost all patients with advanced ENKTL die of their disease. The rational identification of potential novel therapeutic targets in ENKTL would be greatly aided by a more complete understanding of its molecular pathogenesis. We have identified atypical NK cell populations in untreated ENKTL patient samples. These atypical NK cells consistently showed an undifferentiated immunophenotype reminiscent of immature NK developmental stages. As cellular differentiation depends on epigenetic modifications and EBV is known to disrupt epigenetic patterns, we performed genome-wide DNA methylation profiling of ENKTL tumors (n=31 patients) using Illumina MethylationEPIC BeadChip arrays. We uncovered an unprecedented degree of epigenetic dysregulation in ENKTL, primarily involving extensive DNA hypermethylation. In the majority of ENKTL cases, greater than 50% of all CpG islands were hypermethylated, thus representing the most hypermethylated tumor type identified relative to available pan-cancer data (TCGA). In order to explore strategies to target the aberrant DNA hypermethylation in ENKTL, we exposed ENKTL cell lines YT and NK-92 to the demethylating agent 5-azacytidine (5-aza). We observed an unusually high sensitivity of ENKTL cell lines to 5-aza when compared to various other hematologic cancer cell lines, including several EBV-positive lymphoma lines. Hypomethylating agents altered DNA methylation at gene promoters and led to re-expression of epigenetically-silenced tumor suppressor genes in ENKTL cells. We also found synergistic inhibition of in vitro cell growth when combining 5-aza with the standard-of-care chemotherapeutic agents oxaliplatin and gemcitabine. Finally, through engraftment of primary ENKTL patient tumor cells, we have established a patient-derived xenograft (PDX) ENKTL mouse model. In this model, treatment with 5-aza resulted in profound cytoreduction, phenotypic and molecular differentiation of ENKTL cells, as well as significantly prolonged survival. In summary, we report massive, widespread DNA hypermethylation in ENKTL that exceeds the degree of hypermethylation found in other profiled cancers, including other EBV-positive malignancies. We hypothesize that epigenetic dysregulation plays a central role in ENKTL and rational targeting with epigenetic therapies may provide therapeutic benefit to patients. Our ongoing studies aim to identify the optimal epigenetic therapy and potential synergy with chemotherapy in preclinical models, thus providing the basis for novel treatments for ENKTL.

Citation Format: Christoph Weigel, Bethany L. Mundy-Bosse, Yue-Zhong Wu, Kathleen McConnell, Anjali Mishra, Michael A. Caligiuri, Robert A. Baiocchi, Yaso Natkunam, Pierluigi Porcu, Jonathan Brammer, Aharon G. Freud, Christopher C. Oakes. Extranodal natural killer/T cell lymphoma (ENKTL) exhibits an unprecedented degree of global DNA hypermethylation, providing a potent targeted therapy in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-102.

[The experimental study of diquat on the half-Lethal dose and pothological injuny of related organs in wistor rats]

Objective: To explore the acute toxicity of Diquat in mice and to calculate the median lethal dose (LD(50)) of Diquat to rats and observe the pathological changes of tissues and organs in rats with different concentrations of Diquat. Methods: Diquat solution of 50 mg/kg was prepared freshly with 1 000 mg of Diquat and dilute the solution with water to a total of 20 ml. A total of 99 healthy adult male Wistar rats were randomly divided into part one, part two and control groups. In the first part, 36 rats were randomly divided into 4 groups: 100 mg/kg group, 200 mg/kg group, 300 mg/kg group and 400 mg/kg group, which were treated with 100 mg/kg, 200 mg/kg, 300 mg/kg and 400 mg/kg of Diquat solution by gavage, respectively. The death and symptoms of poisoning after intragastric administration were recorded, and the maximum tolerated dose and absolute lethal dose were measured. In the second part, 54 rats were randomly divided into 6 groups: 200 mg/kg group, 220 mg/kg group, 240 mg/kg group, 260 mg/kg、280 mg/kg group and 300 mg/kg group, whichwere treated with 200 mg/kg, 220 mg/kg, 240 mg/kg, 260 mg/kg, 280 mg/kg and 300 mg/kg of Diquat solution by gavage, respectively. The survival of rats in different concentration of Diquat was observed and the LD(50) was calculated by Excel processing the formula of Koch's method. The control group were given equal volume water under the same experimental conditions. And moreover, the lungs, kidneys, hearts, livers, and brain tissues were collected and fixed by formaldehyde, embedded by paraffin, and sectioned for histopathological light microscopy. Results: The maximum tolerated dose was 240 mg/kg and the absolute lethal dose was 300 mg/kg. The LD(50) of Diquat for Rats was 280.58 mg/kg. The high-dose group had significantly more organ damage than the low-dose group after diquat poisoning. Conclusion: The determination of the half-lethal dose of diquat, at the same time observed multiple organs damaged in rats after the diquat quickly poisoned. Kidneys, lungs and heart might be the main organ which was heavily damaged. With the extension of observation time, the organ damage of rats exposed to small doses gradually stabilized.

[Observation and prevention measures against adverse reaction to intratympanic corticosteroid injections]

Objective:To investigate clinical characteristic and incidence of the adverse reaction to tympanic injection. The incidence rates of adverse reaction were also compared after improvement of anesthetic method and changed ratio of methylprednisolone. Method: A retrospective analysis of 712 cases (1 928 injections) of receiving injection in a medical center, to explore the overall and classified adverse reactions, as well as effects of age and gender and frequency on adverse reactions. According to the clinical characteristics of the early stage, the incidence of adverse reaction was observed after the application of anesthesia warming method and the change of methylprednisolone ratio. Result: Adverse reaction was found in 76 cases which included 62 cases of mild reactions, 4 cases of severe reactions and 10 cases of glucocorticoid-related reactions. Overall, 10.67% of patients had adverse reactions. There was no correlation between adverse reactions and age, gender or frequency. The incidence of vertigo was decreased after the application of improved anesthesia (P<0.05). The incidence of pain of joint methylprednisolone-and-lidocaine injection was lower than that of methylprednisolone injection (P<0.05). Conclusion: Intratympanic injection is a safe treatment, to some extent, although there is low incidence of adverse effects of it. At the same time, anesthetic warming method and changing the ratio of methylprednisolone can further reduce the incidence of vertigo and pain.

Broadband Terahertz Generation via the Interface Inverse Rashba-Edelstein Effect

Novel mechanisms for electromagnetic wave emission in the terahertz frequency regime emerging at the nanometer scale have recently attracted intense attention for the purpose of searching next-generation broadband THz emitters. Here, we report broadband THz emission, utilizing the interface inverse Rashba-Edelstein effect. By engineering the symmetry of the Ag/Bi Rashba interface, we demonstrate a controllable THz radiation (∼0.1-5  THz) waveform emitted from metallic Fe/Ag/Bi heterostructures following photoexcitation. We further reveal that this type of THz radiation can be selectively superimposed on the emission discovered recently due to the inverse spin Hall effect, yielding a unique film thickness dependent emission pattern. Our results thus offer new opportunities for versatile broadband THz radiation using the interface quantum effects.

[A group of occupational acute methyl bromide poisoning incident]

Objective: To investigate a mass of occupational acute methyl bromide poisoning incident and analyzed their clinical data. Methods: To investigate an incident a mass of occupational acute methyl bromide poisoning in occurred in Shandong province in November 2016, and the clinical datas of 3 cases of severe patients with methyl bromide poisoning were analysed. Results: This event was a sudden occupational poisoning incident. Lack of vocational training and irregularities is the main reason for the accident 3 patients with nervous system, respiratory system, circulatory system, urinary system damage is given priority to, after comprehensive rescue treatment, 2 cases died and 1 case survived. Conclusions: Methyl bromide can cause severe poisoning, has high mortality in patients with acute severe poisoning.

Midostaurin, bortezomib and MEC in relapsed/refractory acute myeloid leukemia

Targeting aberrant tyrosine kinase activity may impact clinical outcome in acute myeloid leukemia (AML). We conducted a phase I study of the tyrosine kinase inhibitor midostaurin with bortezomib alone and in combination with chemotherapy in patients with AML. Patients on dose levels 1 and 2 (DL1 & 2) received midostaurin 50 mg bid and escalating doses of bortezomib (1 to 1.3 mg/m2). Patients on DL3 or higher received midostaurin and bortezomib following chemotherapy with mitoxantrone, etoposide, cytarabine (MEC). None of the patients enrolled to DL1 & 2 had dose-limiting toxicities (DLTs) or a clinical response. Among patients enrolled to DL3 or higher, DLTs were peripheral neuropathy, decrease in ejection fraction and diarrhea. A 56.5% CR rate and 82.5% overall response rate (CR + CR with incomplete neutrophil or platelet count recovery) were observed. The midostaurin/bortezomib/MEC combination is active in refractory/relapsed AML, but is associated with expected drug-related toxicities (NCT01174888).

Ultrafast spin exchange-coupling torque via photo-excited charge-transfer processes

Optical control of spin is of central importance in the research of ultrafast spintronic devices utilizing spin dynamics at short time scales. Recently developed optical approaches such as ultrafast demagnetization, spin-transfer and spin-orbit torques open new pathways to manipulate spin through its interaction with photon, orbit, charge or phonon. However, these processes are limited by either the long thermal recovery time or the low-temperature requirement. Here we experimentally demonstrate ultrafast coherent spin precession via optical charge-transfer processes in the exchange-coupled Fe/CoO system at room temperature. The efficiency of spin precession excitation is significantly higher and the recovery time of the exchange-coupling torque is much shorter than for the demagnetization procedure, which is desirable for fast switching. The exchange coupling is a key issue in spin valves and tunnelling junctions, and hence our findings will help promote the development of exchange-coupled device concepts for ultrafast coherent spin manipulation.

Light can provide ultrafast ways of spin manipulation in magnetic materials, but existing methods are limited by long thermal recovery or low temperature. Here, the authors demonstrate ultrafast spin precession via optical charge-transfer processes in exchange-coupled Fe/CoO at room temperature.

Quantitative study of the quadratic magneto-optical Kerr effects in Fe films

We present a rotating field method to separate the linear and quadratic magneto-optical Kerr effects (LMOKE and QMOKE) in Fe/GaAs(001) films. The LMOKE is isotropic in crystal orientation, while the QMOKE has both isotropic and anisotropic contributions. The experimental observation is well explained by Yeh's 4×4 matrix formalism. We also report the incident angle and the thickness dependences of the LMOKE and QMOKE, and extract the material's index of refraction n and the magneto-optical coupling constant K and G. The study gives a full description of the Kerr effect in Fe films, and the proposed method can be applied to other magneto-optical coupling systems.

Prognostic and biologic significance of DNMT3B expression in older patients with cytogenetically normal primary acute myeloid leukemia

DNMT3B encodes a DNA methyltransferase implicated in aberrant epigenetic changes contributing to leukemogenesis. We tested whether DNMT3B expression, measured by NanoString nCounter assay, associates with outcome, gene and microRNA expression and DNA methylation profiles in 210 older (⩾60 years) adults with primary, cytogenetically normal acute myeloid leukemia (CN-AML). Patients were dichotomized into high versus low expressers using median cut. Outcomes were assessed in the context of known CN-AML prognosticators. Gene and microRNA expression, and DNA methylation profiles were analyzed using microarrays and MethylCap-sequencing, respectively. High DNMT3B expressers had fewer complete remissions (CR; P=0.002) and shorter disease-free (DFS; P=0.02) and overall (OS; P<0.001) survival. In multivariable analyses, high DNMT3B expression remained an independent predictor of lower CR rates (P=0.04) and shorter DFS (P=0.04) and OS (P=0.001). High DNMT3B expression associated with a gene expression profile comprising 363 genes involved in differentiation, proliferation and survival pathways, but with only four differentially expressed microRNAs (miR-133b, miR-148a, miR-122, miR-409-3p) and no differential DNA methylation regions. We conclude that high DNMT3B expression independently associates with adverse outcome in older CN-AML patients. Gene expression analyses suggest that DNMT3B is involved in the modulation of several genes, although the regulatory mechanisms remain to be investigated to devise therapeutic approaches specific for these patients.

Comparative analysis of mucosal immunity to Mycoplasma hyopneumoniae in Jiangquhai porcine lean strain and DLY piglets

The Jiangquhai porcine lean strain (JQHPL) is a new pork meat-type strain that has been developed in recent years from the parent lines Duroc, Fengjing, and Jiangquhai pigs (DurocxFengjing pigxJiangquhai pig). Enzootic pneumonia (EP) in pigs induced by Mycoplasma hyopneumoniae (M. hyopneumoniae) is a chronic respiratory disease of pigs, generating high economic losses in the swine industry. Here, we investigated the degree of resistance to M. hyopneumoniae for the Jiangquhai porcine lean strain and the Duroc x Landrace x Yorkshire (DLY) pigs, which are Western commercial pigs that have been introduced in China. A total of 209 DLY piglets and 221 JQHPL piglets from 19 Landrace x Yorkshire and 22 JQHPL M. hyopneumoniae positive gestating sows with different expected dates of confinement were selected and raised in the same M. hyopneumoniae positive farrowing barn. When the oldest suckling piglets were 37 days old, nasal swabs were collected from all the piglets (ranging from 4 to 37 days old) to detect the M. hyopneumoniae pathogen using n-PCR and M. hyopneumoniae specific SIgA using ELISA. Positive M. hyopneumoniae infection rates in both the strains increased with age; however, positive rates for JQHPL were lower compared to DLY at 14 to 35 days old. The level of the specific SIgA rose rapidly in JQHPL respiratory tracts, particularly in piglets 21 to 35 days in age compared to DLY piglets of the same age; however, the level of the specific SIgA in DLY also marginally increased. In conclusion, JQHPL pigs exhibits higher resistance to M. hyopneumoniae compared to DLY. It is possible that this characteristic is caused by the faster and stronger mucosal immunity phenotype of the JQHPL strain.

SPARC promotes leukemic cell growth and predicts acute myeloid leukemia outcome

Aberrant expression of the secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) gene, which encodes a matricellular protein that participates in normal tissue remodeling, is associated with a variety of diseases including cancer, but the contribution of SPARC to malignant growth remains controversial. We previously reported that SPARC was among the most upregulated genes in cytogenetically normal acute myeloid leukemia (CN-AML) patients with gene-expression profiles predictive of unfavorable outcome, such as mutations in isocitrate dehydrogenase 2 (IDH2-R172) and overexpression of the oncogenes brain and acute leukemia, cytoplasmic (BAALC) and v-ets erythroblastosis virus E26 oncogene homolog (ERG). In contrast, SPARC was downregulated in CN-AML patients harboring mutations in nucleophosmin (NPM1) that are associated with favorable prognosis. Based on these observations, we hypothesized that SPARC expression is clinically relevant in AML. Here, we found that SPARC overexpression is associated with adverse outcome in CN-AML patients and promotes aggressive leukemia growth in murine models of AML. In leukemia cells, SPARC expression was mediated by the SP1/NF-κB transactivation complex. Furthermore, secreted SPARC activated the integrin-linked kinase/AKT (ILK/AKT) pathway, likely via integrin interaction, and subsequent β-catenin signaling, which is involved in leukemia cell self-renewal. Pharmacologic inhibition of the SP1/NF-κB complex resulted in SPARC downregulation and leukemia growth inhibition. Together, our data indicate that evaluation of SPARC expression has prognosticative value and SPARC is a potential therapeutic target for AML.

Epigenetics meets genetics in acute myeloid leukemia: clinical impact of a novel seven-gene score

PURPOSE

Molecular risk stratification of acute myeloid leukemia (AML) is largely based on genetic markers. However, epigenetic changes, including DNA methylation, deregulate gene expression and may also have prognostic impact. We evaluated the clinical relevance of integrating DNA methylation and genetic information in AML.

METHODS

Next-generation sequencing analysis of methylated DNA identified differentially methylated regions (DMRs) associated with prognostic mutations in older (≥ 60 years) cytogenetically normal (CN) patients with AML (n = 134). Genes with promoter DMRs and expression levels significantly associated with outcome were used to compute a prognostic gene expression weighted summary score that was tested and validated in four independent patient sets (n = 355).

RESULTS

In the training set, we identified seven genes (CD34, RHOC, SCRN1, F2RL1, FAM92A1, MIR155HG, and VWA8) with promoter DMRs and expression associated with overall survival (OS; P ≤ .001). Each gene had high DMR methylation and lower expression, which were associated with better outcome. A weighted summary expression score of the seven gene expression levels was computed. A low score was associated with a higher complete remission (CR) rate and longer disease-free survival and OS (P < .001 for all end points). This was validated in multivariable models and in two younger (< 60 years) and two older independent sets of patients with CN-AML. Considering the seven genes individually, the fewer the genes with high expression, the better the outcome. Younger and older patients with no genes or one gene with high expression had the best outcomes (CR rate, 94% and 87%, respectively; 3-year OS, 80% and 42%, respectively).

CONCLUSION

A seven-gene score encompassing epigenetic and genetic prognostic information identifies novel AML subsets that are meaningful for treatment guidance.

Clinical role of microRNAs in cytogenetically normal acute myeloid leukemia: miR-155 upregulation independently identifies high-risk patients

PURPOSE

To evaluate the impact of miR-155 on the outcome of adults with cytogenetically normal (CN) acute myeloid leukemia (AML) in the context of other clinical and molecular prognosticators and to gain insight into the leukemogenic role of this microRNA.

PATIENTS AND METHODS

We evaluated 363 patients with primary CN-AML. miR-155 levels were measured in pretreatment marrow and blood by NanoString nCounter assays that quantified the expression of the encoding gene MIR155HG. All molecular prognosticators were assessed centrally. miR-155-associated gene and microRNA expression profiles were derived using microarrays.

RESULTS

Considering all patients, high miR-155 expression was associated with a lower complete remission (CR) rate (P < .001) and shorter disease-free survival (P = .001) and overall survival (OS; P < .001) after adjusting for age. In multivariable analyses, high miR-155 expression remained an independent predictor for a lower CR rate (P = .007) and shorter OS (P < .001). High miR-155 expressers had approximately 50% reduction in the odds of achieving CR and 60% increase in the risk of death compared with low miR-155 expressers. Although high miR-155 expression was not associated with a distinct microRNA expression profile, it was associated with a gene expression profile enriched for genes involved in cellular mechanisms deregulated in AML (eg, apoptosis, nuclear factor-κB activation, and inflammation), thereby supporting a pivotal and unique role of this microRNA in myeloid leukemogenesis.

CONCLUSION

miR-155 expression levels are associated with clinical outcome independently of other strong clinical and molecular predictors. The availability of emerging compounds with antagonistic activity to microRNAs in the clinic provides the opportunity for future therapeutic targeting of miR-155 in AML.

Novel chiral magnetic domain wall structure in Fe/Ni/Cu(001) films

Using spin-polarized low energy electron microscopy, we discovered a new type of domain wall structure in perpendicularly magnetized Fe/Ni bilayers grown epitaxially on Cu(100). Specifically, we observed unexpected Néel-type walls with fixed chirality in the magnetic stripe phase. Furthermore, we find that the chirality of the domain walls is determined by the film growth order with the chirality being right handed in Fe/Ni bilayers and left handed in Ni/Fe bilayers, suggesting that the underlying mechanism is the Dzyaloshinskii-Moriya interaction at the film interfaces. Our observations may open a new route to control chiral spin structures using interfacial engineering in transition metal heterostructures.

Aberrant overexpression of IL-15 initiates large granular lymphocyte leukemia through chromosomal instability and DNA hypermethylation

How inflammation causes cancer is unclear. Interleukin-15 (IL-15) is a pro-inflammatory cytokine elevated in human large granular lymphocyte (LGL) leukemia. Mice overexpressing IL-15 develop LGL leukemia. Here, we show that prolonged in vitro exposure of wild-type (WT) LGL to IL-15 results in Myc-mediated upregulation of aurora kinases, centrosome aberrancies, and aneuploidy. Simultaneously, IL-15 represses miR-29b via induction of Myc/NF-κBp65/Hdac-1, resulting in Dnmt3b overexpression and DNA hypermethylation. All this is validated in human LGL leukemia. Adoptive transfer of WT LGL cultured with IL-15 led to malignant transformation in vivo. Drug targeting that reverses miR-29b repression cures otherwise fatal LGL leukemia. We show how excessive IL-15 initiates cancer and demonstrate effective drug targeting for potential therapy of human LGL leukemia.

Prognostic significance of the European LeukemiaNet standardized system for reporting cytogenetic and molecular alterations in adults with acute myeloid leukemia

PURPOSE

To evaluate the prognostic significance of the international European LeukemiaNet (ELN) guidelines for reporting genetic alterations in acute myeloid leukemia (AML).

PATIENTS AND METHODS

We analyzed 1,550 adults with primary AML, treated on Cancer and Leukemia Group B first-line trials, who had pretreatment cytogenetics and, for cytogenetically normal patients, mutational status of NPM1, CEBPA, and FLT3 available. We compared complete remission (CR) rates, disease-free survival (DFS), and overall survival (OS) among patients classified into the four ELN genetic groups (favorable, intermediate-I, intermediate-II, adverse) separately for 818 younger (age < 60 years) and 732 older (age ≥ 60 years) patients.

RESULTS

The percentages of younger versus older patients in the favorable (41% v 20%; P < .001), intermediate-II (19% v 30%; P < .001), and adverse (22% v 31%; P < .001) genetic groups differed. The favorable group had the best and the adverse group the worst CR rates, DFS, and OS in both age groups. Both intermediate groups had significantly worse outcomes than the favorable but better than the adverse group. Intermediate-I and intermediate-II groups in older patients had similar outcomes, whereas the intermediate-II group in younger patients had better OS but not better CR rates or DFS than the intermediate-I group. The prognostic significance of ELN classification was confirmed by multivariable analyses. For each ELN group, older patients had worse outcomes than younger patients.

CONCLUSION

The ELN classification clearly separates the genetic groups by outcome, supporting its use for risk stratification in clinical trials. Because they have different proportions of genetic alterations and outcomes, younger and older patients should be reported separately when using the ELN classification.

Abstract CT-06: The combination of bortezomib (BOR) and decitabine (DEC): A phase I trial in patients (pts) with acute myeloid leukemia (AML) targeting FLT3 expression

Most pts with AML are not cured with conventional chemotherapy regimens. Gain of function mutations & overexpression of tyrosine kinase (TK) receptors (ie KIT & FLT3) are associated with leukemogenesis and poor outcome & represent therapeutic targets. The use of TK inhibitors in AML has been disappointing. Recently we showed that BOR downregulates KIT in AML cells by upregulating miR-29b that disrupts a KIT transactivating complex comprising SP1 and NFκB (p65). In silico we found SP1 & p65 binding sites also in the FLT3 promoter region & speculated that FLT3 may be regulated similarly. Utilizing chromatin immunoprecipitation (CHIP) in MV4-11 cells expressing high FLT3 levels we showed enrichment of SP1 (1.6 fold) & p65 (3.1 fold) vs IgG control on the FLT3 promoter. Cotransfection of a luciferase reporter harboring the FLT3 promoter with SP1 or p65 vectors in 293T cells increased luciferase activity (3.1 & 3.0. fold); siRNA mediated knock-down of SP1 or p65 decreased activity (0.5 & 0.7 fold). In KG1 cells with low FLT3 levels, overexpression of SP1 or p65 increased FLT3 (1.7 & 1.6 fold); in MV4-11 cells siRNA-mediated knockdown of SP1 or p65 decreased FLT3 (0.05 & 0.3 fold) mRNA & protein. Since miR-29b can disrupt the SP1/p65 complex we overexpressed miR-29b in MV4-11 cells, which consequently downregulated FLT3 mRNA & protein level in MV4-11 cells to barely detectable levels. Both BOR & DEC can upregulate miR-29b; thus these drugs potentially decrease FLT3. Indeed BOR (60nM at 24h) or DEC (2.5µM at 48h) led to decreased FLT3 in MV4-11 cells (&lt;.001 & 0.5 fold) & in primary AML blasts (0.28 & 0.42 fold). We concluded that BOR & DEC target the expression of FLT3 via upregulation of miR-29b & disruption of the SP1/p65 complex. To validate these results, we assessed the expression of FLT3 in AML pts enrolled on a Phase I clinical trial (NCT00703300) that tested the BOR & DEC combination. Pts with relapsed/refractory AML or age &gt;60 years with previously untreated disease received DEC at 20mg/m2 IV daily on days 1-10. BOR was gradually dose escalated to 1.3 mg/m2 given on days 5, 8, 12 & 15. Cycles were repeated every 28 days. Pretreatment and day 26 expression levels of FLT3 and miR-29b were assessed. 19 patients were enrolled with a median age of 69 years (range: 32-83). Pts received a median of 2 cycles of therapy (range, 1-14 cycles). Febrile neutropenia & infectious complications were frequent. BOR & DEC at target doses were tolerable; neuropathy following repetitive cycles of BOR limited its administration. 7 pts achieved disease remission. Consistent with our preclinical results, miR-29b expression increased (median fold change: 3.9) and FLT3 expression levels decreased (median fold change: 0.4). As the FLT3 targeting results are encouraging a phase II study of BOR & DEC combination is being planned with modifications of BOR dosing to avoid neuropathy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr CT-06. doi:1538-7445.AM2012-CT-06

Electric-field control of nonvolatile magnetization in Co40Fe40B20/Pb(Mg(1/3)Nb(2/3))(0.7)Ti(0.3)O3 structure at room temperature

We report a large and nonvolatile bipolar-electric-field-controlled magnetization at room temperature in a Co(40)Fe(40)B(20)/Pb(Mg(1/3)Nb(2/3))(0.7)Ti(0.3)O(3) structure, which exhibits an electric-field-controlled looplike magnetization. Investigations on the ferroelectric domains and crystal structures with in situ electric fields reveal that the effect is related to the combined action of 109° ferroelastic domain switching and the absence of magnetocrystalline anisotropy in Co(40)Fe(40)B(20). This work provides a route to realize large and nonvolatile magnetoelectric coupling at room temperature and is significant for applications.

Age-related prognostic impact of different types of DNMT3A mutations in adults with primary cytogenetically normal acute myeloid leukemia

PURPOSE

To determine the frequency of DNMT3A mutations, their associations with clinical and molecular characteristics and outcome, and the associated gene- and microRNA-expression signatures in primary cytogenetically normal acute myeloid leukemia (CN-AML).

PATIENTS AND METHODS

Four hundred fifteen previously untreated adults were analyzed for DNMT3A mutations and established prognostic gene mutations and expression markers. Gene- and microRNA-expression profiles were derived using microarrays.

RESULTS

Younger (< 60 years; n = 181) and older (≥ 60 years; n = 234) patients had similar frequencies of DNMT3A mutations (35.3% v 33.3%). Missense mutations affecting arginine codon 882 (R882-DNMT3A) were more common (n = 92; 62%) than those affecting other codons (non-R882-DNMT3A). DNMT3A-mutated patients did not differ regarding complete remission rate, but had shorter disease-free survival (DFS; P = .03) and, by trend, overall survival (OS; P = .07) than DNMT3A-wild-type patients. In multivariable analyses, DNMT3A mutations remained associated with shorter DFS (P = .01), but not with shorter OS. When analyzed separately, the two DNMT3A mutation types had different significance by age group. Younger patients with non-R882-DNMT3A mutations had shorter DFS (P = .002) and OS (P = .02), whereas older patients with R882-DNMT3A mutations had shorter DFS (P = .005) and OS (P = .002) after adjustment for other clinical and molecular prognosticators. Gene- and microRNA-expression signatures did not accurately predict DNMT3A mutational status.

CONCLUSION

DNMT3A mutations are frequent in CN-AML, and their clinical significance seems to be age dependent. DNMT3A-R882 mutations are associated with adverse prognosis in older patients, and non-R882-DNMT3A mutations are associated with adverse prognosis in younger patients. Low accuracy of gene- and microRNA-expression signatures in predicting DNMT3A mutation status suggested that the role of these mutations in AML remains to be elucidated.

Clinical outcome and gene- and microRNA-expression profiling according to the Wilms tumor 1 (WT1) single nucleotide polymorphism rs16754 in adult de novo cytogenetically normal acute myeloid leukemia: a Cancer and Leukemia Group B study

BACKGROUND

The alleles of the Wilms tumor 1 (WT1) polymorphism rs16754 harbor adenine (A) or guanine (G). Recently, rs16754 has been reported to affect the outcome of patients with cytogenetically normal acute myeloid leukemia. To validate this finding, we investigated pretreatment features and outcome associated with rs16754 in a large cohort of patients with cytogenetically normal acute myeloid leukemia.

DESIGN AND METHODS

Four-hundred and thirty-three intensively treated and molecularly characterized cytogenetically normal patients with de novo acute myeloid leukemia (18-83 years old) were analyzed for rs16754. To gain biological insights, we studied the gene- and microRNA-expression profiles for associations with rs16754.

RESULTS

Three-hundred and nine (71%) patients were homozygous for A (WT1(AA)), 112 (26%) were heterozygous (WT1(AG)) and 12 (3%) were homozygous for G (WT1(GG)). For comparison with previous studies, we grouped WT1(AG) and WT1(GG) patients and compared them with WT1(AA) patients divided into younger (<60 years) and older (≥60 years) adults. We found no independent prognostic impact of WT1(AA). However, WT1(GG) patients, who were less often Caucasian than WT1(AG) (P=0.001) or WT1(AA) (P=0.008) patients, and had TET2 mutations more often than WT1(AG) (P=0.02) patients, had, among patients with FLT3-internal tandem duplication and/or NPM1 wild-type, better disease-free (P=0.02) and overall survival (P=0.04) than WT1(AA) and WT1(AG) patients combined. Unsupervised and supervised analyses of the gene- and microRNA-expression profiles suggested that there were no distinct expression patterns associated with any rs16754 genotype.

CONCLUSIONS

We did not observe the previously reported adverse impact of WT1(AA) but found favorable outcomes associated with the homozygous WT1(GG). Considering its low frequency, confirmatory studies are necessary. The biological significance of rs16754 remains questionable as no distinct expression profiles were associated with the genotypes.

TET2 mutations improve the new European LeukemiaNet risk classification of acute myeloid leukemia: a Cancer and Leukemia Group B study

PURPOSE

To determine the frequency of TET2 mutations, their associations with clinical and molecular characteristics and outcome, and the associated gene- and microRNA-expression signatures in patients with primary cytogenetically normal acute myeloid leukemia (CN-AML).

PATIENTS AND METHODS

Four-hundred twenty-seven patients with CN-AML were analyzed for TET2 mutations by polymerase chain reaction and direct sequencing and for established prognostic gene mutations. Gene- and microRNA-expression profiles were derived using microarrays.

RESULTS

TET2 mutations, found in 23% of patients, were associated with older age (P < .001) and higher pretreatment WBC (P = .04) compared with wild-type TET2 (TET2-wt). In the European LeukemiaNet (ELN) favorable-risk group (patients with CN-AML who have mutated CEBPA and/or mutated NPM1 without FLT3 internal tandem duplication [FLT3-ITD]), TET2-mutated patients had shorter event-free survival (EFS; P < .001) because of a lower complete remission (CR) rate (P = .007), and shorter disease-free survival (DFS; P = .003), and also had shorter overall survival (P = .001) compared with TET2-wt patients. TET2 mutations were not associated with outcomes in the ELN intermediate-I-risk group (CN-AML with wild-type CEBPA and wild-type NPM1 and/or FLT3-ITD). In multivariable models, TET2 mutations were associated with shorter EFS (P = .004), lower CR rate (P = .03), and shorter DFS (P = .05) only among favorable-risk CN-AML patients. We identified a TET2 mutation-associated gene-expression signature in favorable-risk but not in intermediate-I-risk patients and found distinct mutation-associated microRNA signatures in both ELN groups.

CONCLUSION

TET2 mutations improve the ELN molecular-risk classification in primary CN-AML because of their adverse prognostic impact in an otherwise favorable-risk patient subset. Our data suggest that these patients may be candidates for alternative therapies.

DNA methylation changes in a human cell model of breast cancer progression

Epigenetic inactivation of genes by DNA hypermethylation plays an important role in carcinogenesis. An in vitro model of human breast epithelial cell transformation was used to study epigenetic changes induced by estradiol during the neoplastic process. Different stages of tumor initiation and progression are represented in this model being MCF-10F the normal stage; trMCF cells, the transformed stage; bsMCF cells, the invasive stage and, caMCF cells, the tumor stage. Global methylation studies by restriction landmark genomic scanning (RLGS) showed an increased DNA methylation during the in the invasive and tumor stages. Expression studies showed that NRG1 (neuregulin 1), CSS3 (chondroitin sulfate synthase 3) and SNIP (SNAP-25-interacting protein) were downregulated in the invasive and tumor cells. The transformed cells showed low expression of STXBP6 (amysin) compared to the parental cells MCF-10F. The treatment of these cells with the demethylating agent 5-aza-dC alone or in combination with the histone deacetylase inhibitor trichostatin increased the expression of NRG1, STXBP6, CSS3 and SNIP confirming that DNA methylation plays an important role in the regulation of the expression of these genes. The NRG1 exon 1 has a region located between -136 and +79 (considering +1, the translational initiation site) rich in CpG sites that was analyzed by methylation specific PCR (MSP). NRG1 exon 1 showed progressive changes in the methylation pattern associated with the progression of the neoplastic process in this model; NRG1 exon 1 was unmethylated in MCF-10F and trMCF cells, becoming hypermethylated in the invasive (bsMCF) and tumor (caMCF) stages. Studies of human breast tissue samples showed that NRG1 exon 1 was partially methylated in 14 out of 17 (82.4%) invasive carcinomas although it was unmethylated in normal tissues (8 out of 10 normal breast tissue samples). Furthermore, NRG1 exon 1 was partially methylated in 9 out of 14 (64.3%) morphologically normal tissue samples adjacent to invasive carcinomas.

Direct measurement of rotatable and frozen CoO spins in exchange bias system of CoO/Fe/Ag(001)

The exchange bias of epitaxially grown CoO/Fe/Ag(001) was investigated using x-ray magnetic circular dichroism and x-ray magnetic linear dichroism (XMLD) techniques. A direct XMLD measurement on the CoO layer during the Fe magnetization reversal shows that the CoO compensated spins are rotatable at thinner thickness and frozen at larger thickness. By a quantitative determination of the rotatable and frozen CoO spins as a function of the CoO film thickness, we find the remarkable result that the exchange bias is well established before frozen spins are detectable in the CoO film. We further show that the rotatable and frozen CoO spins are uniformly distributed in the CoO film.

IDH1 and IDH2 gene mutations identify novel molecular subsets within de novo cytogenetically normal acute myeloid leukemia: a Cancer and Leukemia Group B study

PURPOSE To analyze the frequency and associations with prognostic markers and outcome of mutations in IDH genes encoding isocitrate dehydrogenases in adult de novo cytogenetically normal acute myeloid leukemia (CN-AML). PATIENTS AND METHODS Diagnostic bone marrow or blood samples from 358 patients were analyzed for IDH1 and IDH2 mutations by DNA polymerase chain reaction amplification/sequencing. FLT3, NPM1, CEBPA, WT1, and MLL mutational analyses and gene- and microRNA-expression profiling were performed centrally. Results IDH mutations were found in 33% of the patients. IDH1 mutations were detected in 49 patients (14%; 47 with R132). IDH2 mutations, previously unreported in AML, were detected in 69 patients (19%; 13 with R172 and 56 with R140). R172 IDH2 mutations were mutually exclusive with all other prognostic mutations analyzed. Younger age (< 60 years), molecular low-risk (NPM1-mutated/FLT3-internal tandem duplication-negative) IDH1-mutated patients had shorter disease-free survival than molecular low-risk IDH1/IDH2-wild-type (wt) patients (P = .046). R172 IDH2-mutated patients had lower complete remission rates than IDH1/IDH2wt patients (P = .007). Distinctive microarray gene- and microRNA-expression profiles accurately predicted R172 IDH2 mutations. The highest expressed gene and microRNAs in R172 IDH2-mutated patients compared with the IDH1/IDH2wt patients were APP (previously associated with complex karyotype AML) and miR-1 and miR-133 (involved in embryonal stem-cell differentiation), respectively. CONCLUSION IDH1 and IDH2 mutations are recurrent in CN-AML and have an unfavorable impact on outcome. The R172 IDH2 mutations, previously unreported in AML, characterize a novel subset of CN-AML patients lacking other prognostic mutations and associate with unique gene- and microRNA-expression profiles that may lead to the discovery of novel, therapeutically targetable leukemogenic mechanisms.

Abstract 2717: Higher MN1 expression is an unfavorable prognosticator in older patients (Pts) with cytogenetically normal acute myeloid leukemia (CN-AML): A CALGB study

In younger (&lt;60 y) adult CN-AML pts, high MN1 expression associates with adverse outcome. The prognostic impact of MN1 expression in older pts (&gt;60 y) requires further evaluation. Pre-therapy bone marrow samples from 140 older de novo CN-AML pts (median age 68 y; range 60 – 81 y) enrolled on cytarabine/daunorubicin-based protocols were studied centrally by RT-PCR. Using the median expression value for MN1, as a cutoff pts were grouped as high & low MN1 expressers. Analysis of the mutation status for FLT3-ITD, FLT3-TKD, NPM1, CEBPA & WT1 & gene & microRNA (miR) expression profiling using, respectively, Affymetrix U133 plus 2.0 & OSU CCC v4.0 arrays, were performed centrally. At diagnosis, higher MN1 associated with wild-type NPM1 (P&lt;.001). Median follow-up was 4.0 y for pts alive. High MN1 expressers had lower complete remission (CR; 53% v 80%, P=.001), shorter event-free (EFS; P=.004; 3y 6% v 14%) & overall survival (OS; P=.03; 3y 10% v 23%; Table) rates. In multivariable models, higher MN1 expression independently associated with a lower CR rate & shorter EFS. Comparison of age groups (60-69 y v ≥70 y) revealed that MN1 expression had a stronger prognostic impact on pts ≥70 y (n=61; Table). Gene (294 genes) & miR (21 miRs) expression signatures associated with high MN1 expression were derived. High MN1 pts had higher expression of precursor markers (CD34, PROM1, CD44, KIT, HLA-DRB1, DNTT), known adverse outcome predictors (BAALC, ERG, HGF), anti-apoptotic BCL2, & miR-101 & miR-126, which are linked to hematologic differentiation. Underexpressed were HOX genes, their co-regulators (MEIS1) & HOX-gene embedded miRs (miR-10a, miR-10b). In conclusion, higher MN1 associated with adverse outcome in older CN-AML pts independently of other established prognosticators & had a stronger impact on ≥70 y pts. The expression signatures provide novel information that may elucidate how MN1 contributes to leukemia & help design new therapeutic approaches.Table.Outcomes according to MN1 expression of all pts and, separately, those age 60-69 y and ≥70yOutcome End PointsMN1 expressionAll Pts (n=140)Pts age 60-69 y (n=79)Pts age ≥70 y (n=61)HighLowPHighLowPHighLowP% achieving CR5380.0015480.035181.03EFS, %event-free at 3 y614.00467.11627.007OS, %alive at 3 y1023.031118.44931.006 The clinical endpoints significantly associated with MN1 expression levels are denoted by bold type.Pts were enrolled on CALGB protocols [CALGB 8525, 8923, 9420, 9720 & 10201].

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2717.

Sp1/NFkappaB/HDAC/miR-29b regulatory network in KIT-driven myeloid leukemia

The biologic and clinical significance of KIT overexpression that associates with KIT gain-of-function mutations occurring in subsets of acute myeloid leukemia (AML) (i.e., core binding factor AML) is unknown. Here, we show that KIT mutations lead to MYC-dependent miR-29b repression and increased levels of the miR-29b target Sp1 in KIT-driven leukemia. Sp1 enhances its own expression by participating in a NFkappaB/HDAC complex that further represses miR-29b transcription. Upregulated Sp1 then binds NFkappaB and transactivates KIT. Therefore, activated KIT ultimately induces its own transcription. Our results provide evidence that the mechanisms of Sp1/NFkappaB/HDAC/miR-29b-dependent KIT overexpression contribute to leukemia growth and can be successfully targeted by pharmacological disruption of the Sp1/NFkappaB/HDAC complex or synthetic miR-29b treatment in KIT-driven AML.

Quantum-well states in a double-well system: an example of Cu/Co(Ni)/Cu

The quantum-well (QW) states in the Cu/Co double-well system are studied by first-principles calculations. We have shown that the monolayer Ni or Co as a heterogeneous spacer in Cu QW can not only disturb the QW states extending into the whole structure, but also create new QW states because of the interfaces introduced, resulting in sub-well-confining electrons. If the QW state energy in two sub-wells is close to each other, these two sub-well QW states can couple together. We have also demonstrated that monolayer Co and Ni spacers play different roles for modulating QW states at different energy levels, which also result in a complicated distribution of QW states. The obtained results are in good agreement with experiment data.

Favorable prognostic impact of NPM1 mutations in older patients with cytogenetically normal de novo acute myeloid leukemia and associated gene- and microRNA-expression signatures: a Cancer and Leukemia Group B study

PURPOSE

To analyze the prognostic significance of NPM1 mutations, and the associated gene- and microRNA-expression signatures in older patients with de novo, cytogenetically normal acute myeloid leukemia (CN-AML) treated with intensive chemotherapy.

PATIENTS AND METHODS

One hundred forty-eight adults age >or= 60 years with de novo CN-AML, enrolled onto Cancer and Leukemia Group B protocols 9720 and 10201, were studied at diagnosis for NPM1, FLT3, CEBPA, and WT1 mutations, and gene- and microRNA-expression profiles.

RESULTS

Patients with NPM1 mutations (56%) had higher complete remission (CR) rates (84% v 48%; P < .001) and longer disease-free survival (DFS; P = .047; 3-year rates, 23% v 10%) and overall survival (OS; P < .001; 3-year rates, 35% v 8%) than NPM1 wild-type patients. In multivariable analyses, NPM1 mutations remained independent predictors for higher CR rates (P < .001) and longer DFS (P = .004) and OS (P < .001), after adjustment for other prognostic clinical and molecular variables. Unexpectedly, the prognostic impact of NPM1 mutations was mainly observed in patients >or= 70 years. Gene- and microRNA-expression profiles associated with NPM1 mutations were similar across older patient age groups and similar to those in younger (< 60 years) patients with CN-AML. These profiles were characterized by upregulation of HOX genes and their embedded microRNAs and downregulation of the prognostically adverse MN1, BAALC, and ERG genes.

CONCLUSION

NPM1 mutations have favorable prognostic impact in older patients with CN-AML, especially those age >or= 70 years. The gene- and microRNA-expression profiles suggest that NPM1 mutations constitute a marker defining a biologically homogeneous entity in CN-AML that might be treated with specific and/or targeted therapies across age groups.

Oscillatory magnetic anisotropy originating from quantum well states in Fe films

The magnetic anisotropy of Fe film grown on vicinal Ag(1,1,10) surfaces was studied with the in situ magneto-optic Kerr effect. Below 200 K, strong oscillations of the uniaxial magnetic anisotropy as a function of Fe thickness with a period of 5.7 monolayers are found, which can even cause the easy magnetization axis to oscillate between perpendicular and parallel to the steps. Such novel oscillation of the anisotropy is attributed to the quantum well states of d-band electrons at the Fermi level in the Fe film. This is unlike the previously observed oscillatory behaviors of ferromagnetic films caused by the quantum well states in nonmagnetic interfacing layers.

Identification of novel methylation markers in cervical cancer using restriction landmark genomic scanning

Aberrant methylation of CpG islands in gene promoters often represents an early clonal event in carcinogenesis. Accordingly, defining methylation profiles may be useful for developing marker panels for early detection or predicting the risk of cancer precursors. To identify specific genes frequently methylated in cervical cancer, we conducted methylation profiling of 20 primary human cervical cancers using NotI-based restriction landmark genomic scanning (RLGS). Of 2,172 RLGS fragments analyzed (average, 1,753 CpG islands per patient), 186 RLGS fragments were lost in at least one tumor and 40 were lost in three or more. Methylation was identified in 19 (95%) of 20 tumor samples compared with normal DNA. Bisulfite sequencing was conducted to confirm RLGS results. Of the confirmed markers frequently methylated, we developed Methylight assays for two corresponding genes, nucleolar protein 4 (NOL4), and lipoma HMGIC fusion partner-like protein 4 (LHFPL4), which were methylated in 85% and 55% of cancers, respectively. Using these assays, we further confirmed frequent CpG island methylation in the original cancers and in another independent series of 15 cervical cancers. We also showed methylation at a reduced frequency in a set of carefully reviewed cytology specimens demonstrating cells exfoliated from cancer precursor lesions. In summary, we identified, for the first time, NOL4 and LHFPL4 as novel methylation targets specific for cervical cancer. Inclusion of NOL4 and LHFPL4 in evaluating methylation panels for early detection, risk prediction, and etiologic research on cervical cancer is warranted.

Symmetry-breaking induced exchange bias in ferromagnetic Ni-Cu-Co and Ni-Fe-Co sandwiches grown on a vicinal Cu(001) surface

Ferromagnetic Ni-Cu-Co and Ni-Fe-Co sandwiches were grown epitaxially onto a vicinal Cu(001) substrate and investigated using magneto-optical Kerr effect and x-ray magnetic circular dichroism techniques. We find that the atomic steps of the vicinal surface break the magnetic reversal symmetry to induce an exchange bias in the Ni perpendicular magnetic hysteresis loop. The Ni exchange bias direction can be switched by changing the direction of the in-plane Co magnetization. In addition, the exchange bias can be tailored by changing the Cu or Fe spacer layer thickness.

CpG island methylation in a mouse model of lymphoma is driven by the genetic configuration of tumor cells

Hypermethylation of CpG islands is a common epigenetic alteration associated with cancer. Global patterns of hypermethylation are tumor-type specific and nonrandom. The biological significance and the underlying mechanisms of tumor-specific aberrant promoter methylation remain unclear, but some evidence suggests that this specificity involves differential sequence susceptibilities, the targeting of DNA methylation activity to specific promoter sequences, or the selection of rare DNA methylation events during disease progression. Using restriction landmark genomic scanning on samples derived from tissue culture and in vivo models of T cell lymphomas, we found that MYC overexpression gave rise to a specific signature of CpG island hypermethylation. This signature reflected gene transcription profiles and was detected only in advanced stages of disease. The further inactivation of the Pten, p53, and E2f2 tumor suppressors in MYC-induced lymphomas resulted in distinct and diagnostic CpG island methylation signatures. Our data suggest that tumor-specific DNA methylation in lymphomas arises as a result of the selection of rare DNA methylation events during the course of tumor development. This selection appears to be driven by the genetic configuration of tumor cells, providing experimental evidence for a causal role of DNA hypermethylation in tumor progression and an explanation for the tremendous epigenetic heterogeneity observed in the evolution of human cancers. The ability to predict genome-wide epigenetic silencing based on relatively few genetic alterations will allow for a more complete classification of tumors and understanding of tumor cell biology.

Genetic and epigenetic alterations of the genome are common features of cancers. The relationship between these two types of alterations, however, remains unclear. One type of epigenetic modification—DNA methylation in promoter sequences of genes—is of particular interest, since tumor cells have different patterns of promoter methylation than normal cells. Previous studies on human tumor samples have suggested a link between genetic alterations and the induction of aberrant DNA methylation; however, this link has been difficult to rigorously assess because of the incredible genetic heterogeneity found in human cancer. In this study, a mouse model of T cell lymphoma was used to explore the relationship between genetic and epigenetic modifications experienced by tumor cells. By introducing defined genetic changes into preneoplastic T cells of mice, such as the overexpression of the MYC oncogene and the ablation of tumor suppressor genes, we could carefully evaluate how these genetic changes impacted promoter methylation profiles during development of lymphomas in vivo. We found that the introduction of different genetic insults resulted in unique and diagnostic profiles of promoter methylation. Understanding how these methylation signatures contribute to tumor progression could eventually have diagnostic, prognostic, and therapeutic value for human cancers.

Magnetic bubble domain phase at the spin reorientation transition of ultrathin Fe/Ni/Cu(001) film

Magnetic domain phases of ultrathin Fe/Ni/Cu(001) are studied using photoemission electron microscopy at the spin reorientation transition (SRT). We observe a new magnetic phase of bubble domains within a narrow SRT region after applying a nearly in-plane magnetic field pulse to the sample. By applying the magnetic field pulse along different directions, we find that the bubble domain phase exists only if the magnetic field direction is less than approximately 10 degrees relative to the sample surface. A temperature dependent measurement shows that the bubble domain phase becomes unstable above 370 K.