Background
Central nervous system (CNS) involvement is associated with relapse in childhood acute lymphoblastic leukemia (ALL) and is a diagnostic challenge.
Procedure
In a Nordic/Baltic prospective ...study, we assessed centralized flow cytometry (FCM) of locally fixed cerebrospinal fluid (CSF) samples versus local conventional cytospin‐based cytology (CC) for detecting leukemic cells and evaluating kinetics of elimination of leukemic cells in CSF.
Results
Among 300 patients with newly diagnosed ALL, 87 (29%) had CSF involvement by FCM, while CC was positive in 30 (10%) of 299 patients with available CC data (P < 0.001). Patients with FCM+/CC+ had higher CSF leukemic blast counts compared to patients positive by FCM only (medians: 0.10 vs. 0.017 leukemic blasts/μl, P = 0.006). Patients positive by FCM had higher white blood cell counts in peripheral blood than patients negative by FCM (medians: 45 × 109/l vs. 10 × 109/l, P < 0.001), were younger (medians: 3 years vs. 4 years, P = 0.03), and more frequently had T‐cell ALL (18/87 vs. 16/213, P = 0.001). At treatment day 15, five of 52 patients (10%) who had CSF positive by FCM at diagnosis remained so despite at least two doses of weekly intrathecal chemotherapy.
Conclusions
Longer follow‐up is needed to clarify whether FCM positivity has prognostic significance and is an indicator for intensified CNS‐directed therapy.
Acute infectious spondylodiscitis (AIS) is a serious infection of the spine with rising incidence and a mortality of 3-6%. The role of the immune system in AIS is largely unknown. We performed ...extensive B and T-lymphocyte phenotyping in patients with AIS at diagnosis and after treatment cessation. In this prospective multicentre study, flow cytometric analysis of T and B-lymphocyte subsets was performed in 35 patients at diagnosis and 3 months after treatment cessation. We additionally analysed levels of immunoglobulins and IgG subclasses, serum level and genetic variants of mannose-binding lectin, and somatic hypermutation. A total of 22 (61%) patients had B-lymphocytes below reference limit at baseline, persisting in 7 (30%) patients at follow-up. We found a lower proportion of CD19 + CD27 + IgD+ marginal zone B-lymphocytes and a higher proportion of γδ+ T-lymphocyte receptors compared with controls at both time points. Immunoglobulin levels were elevated at baseline compared to follow-up, and not associated with absolute B-lymphocyte count. In conclusion, a large proportion of AIS patients presented with profound B-lymphocyte deficiency, only partly reversible at follow-up. Identification of immune dysfunction related to AIS may allow for future targeted therapeutic interventions to restore host immunity.
Reduction in minimal residual disease, measured by real-time quantitative PCR or flow cytometry, predicts prognosis in childhood B-cell precursor acute lymphoblastic leukemia. We explored whether ...cells reported as minimal residual disease by flow cytometry represent the malignant clone harboring clone-specific genomic markers (53 follow-up bone marrow samples from 28 children with B-cell precursor acute lymphoblastic leukemia). Cell populations (presumed leukemic and non-leukemic) were flow-sorted during standard flow cytometry-based minimal residual disease monitoring and explored by PCR and/or fluorescence in situ hybridization. We found good concordance between flow cytometry and genomic analyses in the individual flow-sorted leukemic (93% true positive) and normal (93% true negative) cell populations. Four cases with discrepant results had plausible explanations (e.g. partly informative immunophenotype and antigen modulation) that highlight important methodological pitfalls. These findings demonstrate that with sufficient experience, flow cytometry is reliable for minimal residual disease monitoring in B-cell precursor acute lymphoblastic leukemia, although rare cases require supplementary PCR-based monitoring.
Type I interferons (IFN-I) play a critical role in human antiviral immunity, as demonstrated by the exceptionally rare deleterious variants of IFNAR1 or IFNAR2. We investigated five children from ...Greenland, Canada, and Alaska presenting with viral diseases, including life-threatening COVID-19 or influenza, in addition to meningoencephalitis and/or hemophagocytic lymphohistiocytosis following live-attenuated viral vaccination. The affected individuals bore the same homozygous IFNAR2 c.157T>C, p.Ser53Pro missense variant. Although absent from reference databases, p.Ser53Pro occurred with a minor allele frequency of 0.034 in their Inuit ancestry. The serine to proline substitution prevented cell surface expression of IFNAR2 protein, small amounts of which persisted intracellularly in an aberrantly glycosylated state. Cells exclusively expressing the p.Ser53Pro variant lacked responses to recombinant IFN-I and displayed heightened vulnerability to multiple viruses in vitro-a phenotype rescued by wild-type IFNAR2 complementation. This novel form of autosomal recessive IFNAR2 deficiency reinforces the essential role of IFN-I in viral immunity. Further studies are warranted to assess the need for population screening.
Some developmental dual-acting PPARα/γ agonists, such as ragaglitazar, have shown carcinogenic effects in the rodent urinary bladder urothelium after months-years of dosing. We examined early ...(precancerous) changes in the bladder urothelium of rats orally dosed with ragaglitazar, using a newly developed flow cytometric method. Following 3 weeks of oral ragaglitazar dosing, increases in physical size occurred in a generalized fashion in rat bladder urothelial cells, determined by flow cytometry. Protein/DNA measurements confirmed increased protein content of urothelial cells in the bladder, and hypertrophy was observed in the kidney pelvis urothelium by histopathology. In animals exhibiting urothelial hypertrophy, no cell cycle changes were detected in parallel samples of bladder urothelium. Interestingly, urothelial cells from normal rats were found to constitute a unique type of noncycling population, with high G2/M fractions. In summary, our findings showed that in the urothelium of ragaglitazar-treated animals, hypertrophy (increased size and protein content per cell) was an early change, that affected the whole bladder urothelial cell population. The urothelial hypertrophy was primary, i.e., occurred in the absence of similarly pronounced changes in cell cycle distributions. To our knowledge, this is the first report of a direct hypertrophic effect of a PPAR agonist. Urothelial hypertrophy might be a relevant early biological endpoint in mechanistic studies regarding the bladder-carcinogenic effect of PPAR agonists.
We compare outcomes in two large‐scale contemporaneously treated HPV‐positive (HPV+) oropharynx cancer (OPC) cohorts treated with definitive radiotherapy/chemoradiotherapy (RT/CRT). p16‐confirmed ...HPV+ OPC treated between 2007 and 2015 at PMH and DAHANCA were identified. Locoregional failure (LRF), distant metastasis (DM), and overall survival (OS) were compared. Multivariable analysis (MVA) calculated adjusted‐hazard‐ratio (aHR) with 95% confidence interval (95% CI), adjusting for cohort, age, gender, performance status, smoking pack‐years, T‐category and N‐category and chemotherapy. Compared to PMH (n = 701), DAHANCA (n = 1174) contained lower TNM‐8T‐categories (T1‐T2: 77% vs 56%), N‐categories (N0‐N1: 77% vs 67%) and stages (stage I: 63% vs 44% (all P < .001). PMH used standard‐fractionation CRT in 69% (481) while 31% (220) received hypofractionated or moderately accelerated RT‐alone. All DAHANCA patients were treated with moderately accelerated RT; 96% (1129) received nimorazole (NIM) and 73% (856) concurrent weekly cisplatin. DAHANCA had shorter overall‐treatment‐time (P < .001), lower gross tumor (66‐68 vs 70 Gy) and elective neck (50 vs 56 Gy) doses. Median follow‐up was 4.8 years. DAHANCA had higher 5‐year LRF (13% vs 7%, aHR = 0.47 0.34‐0.67), comparable DM (7% vs 12%, aHR = 1.32 0.95‐1.82), but better OS (85% vs 80%, aHR = 1.30 1.01‐1.68). CRT patients had a lower risk of LRF (aHR 0.56 0.39‐0.82), DM (aHR 0.70 0.50‐1.00) and death (aHR 0.39 0.29‐0.52) vs RT‐alone. We observed exemplary outcomes for two large‐scale trans‐Atlantic HPV+ OPC cohorts treated in a similar manner. Concurrent chemotherapy was a strong, independent prognostic factor for all endpoints. Our findings underscore the need for a very careful approach to de‐intensification of treatment for this disease.
What's new?
HPV‐positive oropharyngeal cancer (OPC) represents a unique subgroup which has very different epidemiology, molecular biology, and response to radiotherapy/chemo‐radiotherapy (RT/CRT) than HPV‐negative squamous cell carcinoma of the head and neck (HNSCC). In this study, the authors compared two large cohorts of HPV‐positive OPC, and found significantly better outcomes in patients that routinely received concurrent chemoradiotherapy with cisplatin compared with radiotherapy alone. The authors conclude that these findings underscore the need for a cautious approach to efforts aimed at de‐intensifying treatment for this disease.
Invasion and angiogenesis are major hallmarks of glioblastoma (GBM) growth. While invasive tumor cells grow adjacent to blood vessels in normal brain tissue, tumor cells within neovascularized ...regions exhibit hypoxic stress and promote angiogenesis. The distinct microenvironments likely differentially affect metabolic processes within the tumor cells.
In the present study, we analyzed gene expression and metabolic changes in a human GBM xenograft model that displayed invasive and angiogenic phenotypes. In addition, we used glioma patient biopsies to confirm the results from the xenograft model.
We demonstrate that the angiogenic switch in our xenograft model is linked to a proneural-to-mesenchymal transition that is associated with upregulation of the transcription factors BHLHE40, CEBPB, and STAT3. Metabolic analyses revealed that angiogenic xenografts employed higher rates of glycolysis compared with invasive xenografts. Likewise, patient biopsies exhibited higher expression of the glycolytic enzyme lactate dehydrogenase A and glucose transporter 1 in hypoxic areas compared with the invasive edge and lower-grade tumors. Analysis of the mitochondrial respiratory chain showed reduction of complex I in angiogenic xenografts and hypoxic regions of GBM samples compared with invasive xenografts, nonhypoxic GBM regions, and lower-grade tumors. In vitro hypoxia experiments additionally revealed metabolic adaptation of invasive tumor cells, which increased lactate production under long-term hypoxia.
The use of glycolysis versus mitochondrial respiration for energy production within human GBM tumors is highly dependent on the specific microenvironment. The metabolic adaptability of GBM cells highlights the difficulty of targeting one specific metabolic pathway for effective therapeutic intervention.
Abstract
During the past decade planning of adjuvant radiotherapy (RT) of early breast cancer has changed from two-dimensional (2D) to 3D conformal techniques. In the planning computerised tomography ...(CT) scan both the targets for RT and the organs at risk (OARs) are visualised, enabling an increased focus on target dose coverage and homogeneity with only minimal dose to the OARs. To ensure uniform RT in the national prospective trials of the Danish Breast Cancer Cooperative Group (DBCG), a national consensus for the delineation of clinical target volumes (CTVs) and OARs was required. Material and methods. A CT scan of a breast cancer patient after surgical breast conservation and axillary lymph node (LN) dissection was used for delineation. During multiple dummy-runs seven experienced radiation oncologists contoured all CTVs and OARs of interest in adjuvant breast RT. Two meetings were held in the DBCG Radiotherapy Committee to discuss the contouring and to approve a final consensus. The Dice similarity coefficient (DSC) was used to evaluate the delineation agreement before and after the consensus. Results. The consensus delineations of CTVs and OARs are available online and a table is presented with a contouring description of the individual volumes. The consensus provides recommendations for target delineation in a standard patient both in case of breast conservation or mastectomy. Before the consensus, the average value of the DSC was modest for most volumes, but high for the breast CTV and the heart. After the consensus, the DSC increased for all volumes. Conclusion. The DBCG has provided the first national guidelines and a contouring atlas of CTVs and OARs definition for RT of early breast cancer. The DSC is a useful tool in quantifying the effect of the introduction of guidelines indicating improved inter-delineator agreement. This consensus will be used by the DBCG in our prospective trials.
•Cholinergic tracer binding is described in regions that have not hitherto been explored in human in vivo imaging.•The in vivo cholinergic spatial distribution aligns with immunohistochemical stains ...reported in post-mortem studies.•The spatial distribution of 18FFEOBV PET correlates with regional expression levels of the VAChT-coding SLC18A3 gene.
18Ffluoroetoxybenzovesamicol (18FFEOBV) is a positron emission topography (PET) tracer for the vesicular acetylcholine transporter (VAChT), a protein located predominantly in synaptic vesicles in cholinergic nerve terminals. We aimed to use 18FFEOBV PET to study the cholinergic topography of the healthy human brain.
18FFEOBV PET brain data volumes of healthy elderly humans were normalized to standard space and intensity-normalized to the white matter. Stereotactic atlases of regions of interest were superimposed to describe and quantify tracer distribution. The spatial distribution of 18FFEOBV PET uptake was compared with histological and gene expression data.
Twenty participants of both sexes and a mean age of 73.9 ± 6.0 years, age-range 64; 86, were recruited. Highest tracer binding was present in the striatum, some thalamic nuclei, and the basal forebrain. Intermediate binding was found in most nuclei of the brainstem, thalamus, and hypothalamus; the vermis and flocculonodular lobe; and the hippocampus, amygdala, insula, cingulate, olfactory cortex, and Heschl's gyrus. Lowest binding was present in most areas of the cerebral cortex, and in the cerebellar nuclei and hemispheres. The spatial distribution of tracer correlated with immunohistochemical post-mortem data, as well as with regional expression levels of SLC18A3, the VAChT coding gene.
Our in vivo findings confirm the regional cholinergic distribution in specific brain structures as described post-mortem. A positive spatial correlation between tracer distribution and regional gene expression levels further corroborates 18FFEOBV PET as a validated tool for in vivo cholinergic imaging. The study represents an advancement in the continued efforts to delineate the spatial topography of the human cholinergic system in vivo.
Display omitted
Nano-crystalline Mg2Si (Mg67Si33) and its Si-rich eutectic (Mg47Si53) composition were synthesized by hydrogen desorption-recombination process, casting and rapid solidification techniques. The ...synthesis of Mg2Si meets experimental challenges due to a significant difference in the melting temperatures of Mg (650 °C) and Si (1414 °C) and due to easy vaporization of magnesium metal. As cast alloys were obtained by induction melting the precursors, Mg and Si, followed by the casting and water quenching. These alloys were rapidly solidified using a chill block melt spinning which produces ribbons with fine dendritic morphology and a grain size close to 100 nm. Hydrogen desorption-recombination process of MgH2-Si mixture resulted in a release of ∼4.67 wt % H and formation of Mg2Si. The microstructure of the alloys has been studied using Scanning Electron Microscopy and the relationship between microstructure and electrochemical properties as anodes of the lithium ion batteries was characterised. The electrochemical tests indicate that Si rich eutectic electrode shows a higher charge-discharge capacity than the Mg2Si intermetallic. Rapidly solidified Mg2Si and Mg2Si + Si alloys showed the highest initial discharge capacities of 989 mAh/g and 1283 mAh/g, respectively, superior to the alloys prepared by hydrogen desorption-recombination process and casting. The presence of electrolyte additives FEC (5%) and VC (1%) resulted in the formation of the stable SEI layer and enhanced the cycling capacity of the electrodes. Electrochemical Impedance Spectroscopy (EIS) was used to characterize the anode electrodes on cycling. A mathematical model for accounting the impedance response was utilised. The EIS response showed an increased overall resistance for the Mg2Si eutectic Si-containing alloy electrodes when compared to the electrodes based on a stoichiometric Mg2Si. Long-term cycling resulted in increased charge transfer resistance, which slowed down the electrochemical processes at the surface of the electrodes.
Electrochemical performance of Mg-Si alloys used as anodes of the lithium ion battery significantly improves when the eutectic alloy Mg2Si+Si is subjected to the Rapid Solidification leading to its nanostructuring and in presence of additives to the electrolyte allowing to form a stable SEI layer. Display omitted
•Nanostructured Mg2Si and Mg2Si+Si eutectic alloys as anodes of Li ion battery.•Effect of microstructure on the electrochemical capacity.•Rapid Solidification resulted is a reduced grain size of 100 nm.•VC and FEC electrolyte additives to LiPF6 improved anode performance.•Electrochemical Impedance Spectroscopy was used to analyse cycling stability.
PDF
