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This study surveyed adult web monitor enrollees about the lives of and stress experienced by Japanese children and adolescents during the prolonged coronavirus disease 2019 (COVID-19) pandemic. The survey was conducted on February 10, 2022 (after the sixth wave) and August 19, 2022 (during the seventh wave of the COVID-19 pandemic in Japan), with 231 and 217 survey participants, respectively. The questionnaire was designed so that adults could assess the frequency of exercise, and difficulties experienced by children and adolescents around them. Regarding exercise opportunities, 22% of parents of middle and high school children reported that children’s exercise opportunities “stayed the same” or “increased considerably” in the first survey. Whereas, in the second survey, all parents of middle and high school children reported that children’s exercise opportunities “decreased.” Regarding stress, 17% of parents of adolescents 18 years and older responded that the stress experienced was the “same as before” or “a little less than before” in the first survey, but all of these parents responded “quite a bit” to the same question in the second survey. The findings suggest that the life changes caused by the COVID-19 pandemic may have a significant impact on children and adolescents and may increase stress. The long-term effects of the COVID-19 pandemic on children and adolescents should be further investigated.

After a natural disaster, it is important to maintain the health of the victims, but after the Turkey-Syria earthquake, this information has not yet been provided. Tohoku University has compiled information on maintaining health care after the Great East Japan Earthquake of March 2011 into a booklet, which is available to the public. The purpose of this study is to investigate user satisfaction with this booklet. A total of 505 organizations participated in this study by completing questionnaires and evaluating the booklet. Quantitative responses were analyzed and coded by theme. Open-ended responses indicated that it was difficult for the general public to understand the data in the booklet. This study shows the need to keep in mind the ease of understanding for the general public when providing information on post-disaster care. We hope that this study will lead to better health care information for the victims of the Turkey-Syria earthquake.

Supplementary Figure 2 from Cell Survival under Stress Is Enhanced by a Mitochondrial ATP-Binding Cassette Transporter That Regulates Hemoproteins

Supplementary Material and Methods : Plasma pharmacokinetics of topotecan with and without the ABCG2 inhibitor Ko143. Supplementary Figure S1: RNA expression of ABC transporters in human and mouse Group3 medulloblastoma. Supplementary Figure S2: Abcg2 protein expression in mouse bone marrow from Abcg2-null mice and Group3 medulloblastoma tumor cells. Supplementary Figure S3: Dose-response of chemotherapeutic agents alone or with two Abcg2 inhibitors, Ko143 or Tariquidar. Supplementary Figure S4: Weight measurement and Abcg2 protein expression in mouse Group3 medulloblastoma during treatment. Supplementary Table 1: Affymetrix gene array analysis of genes in the porphyrin pathway in granule neuron progenitors (GNPs) and Mouse Group3 medulloblastoma tumor cells. Supplementary Table 2: Chemotherapeutic drugs tested on mouse Group3 medulloblastoma tumor cells. Supplementary Table 3: Plasma PK paramaters of topotecan after administration as single agent or in combination with the Abcg2 inhibitor Ko143.

Supplementary Figure 3 from Cell Survival under Stress Is Enhanced by a Mitochondrial ATP-Binding Cassette Transporter That Regulates Hemoproteins

Supplementary Figure 4 from Cell Survival under Stress Is Enhanced by a Mitochondrial ATP-Binding Cassette Transporter That Regulates Hemoproteins

While a small number of plasma membrane ABC transporters can export chemotherapeutic drugs and confer drug resistance, it is unknown whether these transporters are expressed or functional in less therapeutically tractable cancers such as Group 3 (G3) medulloblastoma. Herein we show that among this class of drug transporters, only ABCG2 was expressed at highly increased levels in human G3 medulloblastoma and a mouse model of this disease. In the mouse model, Abcg2 protein was expressed at the plasma membrane where it functioned as expected on the basis of export of prototypical substrates. By screening ABC substrates against mouse G3 medulloblastoma tumorspheres in vitro, we found that Abcg2 inhibition could potentiate responses to the clinically used drug topotecan, producing a more than 9-fold suppression of cell proliferation. Extended studies in vivo in this model confirmed that Abcg2 inhibition was sufficient to enhance antiproliferative responses to topotecan, producing a significant survival advantage compared with subjects treated with topotecan alone. Our findings offer a preclinical proof of concept for blockade of ABCG2 transporter activity as a strategy to empower chemotherapeutic responses in G3 medulloblastoma. Cancer Res; 75(18); 3879–89. ©2015 AACR.

The ATP-binding cassette (ABC) transporter ABCB6 localizes to the mitochondria, where it imports porphyrins and up-regulates de novo porphyrin synthesis. If ABCB6 also increases the intracellular heme concentration, it may broadly affect the regulation and physiology of cellular hemoproteins. We tested whether the ability of ABCB6 to accelerate de novo porphyrin biosynthesis alters mitochondrial and extramitochondrial heme levels. ABCB6 overexpression increased the quantity of cytosolic heme but did not affect mitochondrial heme levels. We then tested whether the increased extramitochondrial heme would increase the concentration and/or activity of cellular hemoproteins (hemoglobin, catalase, and cytochrome c oxidase). ABCB6 overexpression increased the activity and quantity of hemoproteins found in several subcellular compartments, and reduction of ABCB6 function (by small interfering RNA or knockout) reversed these findings. In complementary studies, suppression of ABCB6 expression sensitized cells to stress induced by peroxide and cyanide, whereas overexpression of ABCB6 protected against both stressors. Our findings show that the ability of ABCB6 to increase cytosolic heme levels produces phenotypic changes in hemoproteins that protect cells from certain stresses. Collectively, these findings have implications for the health and survival of both normal and abnormal cells, which rely on heme for multiple cellular processes. [Cancer Res 2009;69(13):5560–7]

Supplementary Figure 1 from Cell Survival under Stress Is Enhanced by a Mitochondrial ATP-Binding Cassette Transporter That Regulates Hemoproteins

Introduction: Adolescents affected by disasters need mental health support because they tend to be at risk of developing psychiatric disorders and stress as grown-ups. However, it is difficult to develop and validate a support system for adolescents affected by disasters because it is unknown when and where disasters occur, and there is inadequate data related to this in Japan. Methods: To address these issues, we present a mental health support system for high school students affected by the Great East Japan Earthquake. We hypothesized that mental health support could be provided by classroom teachers and school nurses, who are familiar with high school students. We investigated the psychological state of the affected high school students for three years after the earthquake, and the students in psychological crises received interventions from their class teachers and school nurses. Results: The intervention resulted in improvements in depression and post-traumatic stress reaction (PTSR). Conclusion: These results suggest that our high school-based intervention is a feasible solution for mental health support for adolescents affected by the disaster.

Historical data can determine how adolescents recover from difficult situations such as the Coronavirus disease 2019 (COVID-19) pandemic. This study analysed 3 years of data obtained from high-school students who had been affected by the 2011 Great East Japan Earthquake and consequently evidenced the importance of increasing resilience among affected adolescents. This involved identifying factors contributing to resilience through a model that assessed for each tsunami disaster. This model was determined by assessing the correlation between survivors’ resilience scores and their measured psychological and lifestyle scores. This approach showed that, in all tsunami damage models, resilience was most affected by the depressed emotions. Thus, our approach suggests that interventions for improving the depressed mood may improve resilience in adolescents during the COVID-19 pandemic.

All aerobic organisms require the cofactor heme to survive, but its synthesis requires formation of a potentially toxic intermediate protoporphyrin IX (PPIX). Little is known about the extent of PPIX’s cellular interactions. Here, we report the development of PPB, a biotin-conjugated, PPIX-probe that captures proteins capable of interacting with PPIX. Quantitative proteomics with PPB identified common proteins among a diverse panel of mammalian cell lineages. Pathway and quantitative difference analysis revealed PPB-bound proteins related to iron and heme metabolism and suggested that these processes might be altered by heme/porphyrin synthesis. We show that increased heme/porphyrin synthesis in cells promotes ferroptosis that is pharmacologically distinct from canonical ferroptosis driven by erastin, an inhibitor of the cystine/glutamate antiporter. Proteomic data derived from PPB revealed an interactor, PRDX3, a mitochondrial peroxidase, that modulated heme/porphyrin biosynthesis driven ferroptosis. Consistent with a role in porphyrin-induced ferroptotic death targeted gene knockdown of PRDX3, but not peroxidases, PRDX1 or 2, enhanced porphyrin-induced ferroptotic death. The relationship between increased heme/porphyrin synthesis and ferroptosis was also found in a ferrochelatase-deficient T-lymphoblastoid leukemia cell line, suggesting potential strategy for treating certain cancers. We demonstrate that when the PPB probe is coupled with unbiased proteomics a previously unreported relationship between heme/porphyrin synthesis, and ferroptosis was discovered.

Background To date, there is no systematic overview of glutamate in the dorsolateral prefrontal cortex (DLPFC) of patients with schizophrenia. Here, we meta-analyzed case-control studies of high-field proton magnetic resonance spectroscopy (1H-MRS) investigating glutamate in DLPFC. Additionally, we estimated variance ratios to investigate homo/heterogeneity. Methods Preregistration of the study was performed on September 20, 2019. The predefined literature search on PubMed comprised articles with search terms (magnetic resonance spectroscopy OR MRS) AND (glutamate OR glut∗ OR GLX) AND (schizophrenia OR psychosis OR schizophren∗). Meta-analyses with a fixed- and random-effects model with inverse variance method, DerSimonian-Laird estimator for τ2, and Cohen's d were calculated. For differences in variability, we calculated a random-effects model for measures of variance ratios. The primary study outcome was the difference in glutamate in the DLPFC in cases versus controls. Secondary outcomes were differences in variability. Results The quantitative analysis comprised 429 cases and 365 controls. Overall, we found no group difference (d = 0.03 [95% confidence interval (CI), −0.20 to 0.26], z = 0.28, p = .78). Sensitivity analysis revealed an effect for medication status (Q = 8.35, p = .039), i.e., increased glutamate in antipsychotic-naive patients (d = 0.46 [95% CI, 0.08 to 0.84], z = 2.37, p = .018). Concerning variance ratios, we found an effect of medication status (Q = 16.95, p Conclusions We carefully interpret the higher levels and lower variability in cortical glutamate in antipsychotic-naive patients as a possible key factor resulting from a putative allostatic mechanism. We conclude that care has to be taken when evaluating metabolite levels in clinical samples in which medication might confound findings.

Introduction: Health professionals and support staff need to be prepared for disasters and know how to respond. This study aimed to examine a one-day “Conductor-type disaster healthcare management personnel” training course and its effect among healthcare professionals. Tohoku University and Fukushima Medical University are experienced in disaster response preparedness and they conducted the one-day course comprising multiple sessions at the World Bosai Forum-2019 (WBF-2019). Method: The course introduced the recent activities of four groups: the Practical Disaster Risk Reduction Research Group; the Natural Science Research Group; the Disaster Humanities Research Group; and the Disaster Medicine Research Group. Unifying four scientific areas based on the theory of the disaster cycle, the research field “disaster science” has been created through interdisciplinary cooperation. The participants completed reports, which were then analyzed using the KJ method. Discussion: The program participants wanted to gain practical knowledge about disasters and have a multifaceted perspective on disaster response. Participants who attended other sessions had an interest in comparing their training with the training provided by other sessions on disaster preparedness. Comparisons included determining the effectiveness of high-level disaster medical preparations from a multilateral viewpoint and involving an interdisciplinary research team in disaster medical preparations to prepare for future disaster events. Conclusion: The participants identified that interdisciplinary activities lead to an improvement in knowledge, skills, or attitudes toward disaster preparedness. There needs to be a greater focus on disaster medicine care teams, including research on both past and future disasters.

ATP-binding cassette sub-family G member 2 (ABCG2) is a homodimeric ATP-binding cassette (ABC) transporter that not only has a key role in helping cancer cells to evade the cytotoxic effects of chemotherapy, but also in protecting organisms from multiple xeno- and endobiotics. Structural studies indicate that substrate and inhibitor (ligands) binding to ABCG2 can be differentiated quantitatively by the number of amino acid contacts, with inhibitors displaying more contacts. Although binding is the obligate initial step in the transport cycle, there is no empirical evidence for one amino acid being primarily responsible for ligand binding. By mutagenesis and biochemical studies, we demonstrated that the phylogenetically conserved amino acid residue, F439, was critical for both transport and the binding of multiple substrates and inhibitors. Structural modeling implied that the π-π interactions from each F439 monomer mediated the binding of a surprisingly diverse array of structurally unrelated substrates and inhibitors and that this symmetrical π-π interaction "clamps" the ligand into the binding pocket. Key molecular features of diverse ABCG2 ligands using the π-π clamp along with structural studies created a pharmacophore model. These novel findings have important therapeutic implications because key properties of ligands interacting with ABCG2 have been disovered. Furthermore, mechanistic insights have been revealed by demonstrating that for ABCG2 a single amino acid is essential for engaging and initiating transport of multiple drugs and xenobiotics.

Various traditional festivals have taken place in most of the community in the coastal areas of the Tohoku region before the 2011 Great East Japan earthquake. Recent studies have revealed that reviving these festivals plays a crucial role for people to reconstruct a community life in the tsunami-affected area. Despite the importance of the intangible cultural properties, not only outfits used but also crafts to make those kits were swept away by the 2011 tsunami. Under this background, this research attempts to record the three-dimensional data of those materials used in festivals and folk performing arts. This project aims to construct the database of those props used for the intangible cultural properties and offer three-dimensional data to the disaster-affected area to rebuild their community life. Another goal of this explorative project is to create a methodology of three-dimensional measurement in the field of the disaster humanity science. By scanning cultural properties in disaster-prone areas not only in Japan but also in other countries, the project attempts to connect international networks to discuss the applicability of this method.

Researchers believe that the impact of repeated trauma on mental health is incrementally more significant than the simple additive effect of one event. This study questioned whether this repetition only further worsens people's mental health. We found that they may report more positive changes than those who haven’t. Thus, we hypothesized that repeatedly experiencing difficult situations and suffering might increase post-traumatic growth (PTG). PTG can be defined as "positive psychological changes experienced due to coping with very difficult life situations," leading to positive outcomes and feelings of well-being. We found that those who experienced a disaster in the past were more depressed, anxious, and stressed than those who had never experienced a disaster and now experienced the COVID-19 pandemic. Additionally, past disaster experience led to a more psychological response to the COVID-19 pandemic, which, in turn, led to an increase PTG. Globally, we found that supportive social interactions, including those with family members, could develop PTG during the COVID-19 pandemic and achieve better well-being during the continuation of the pandemic in the future.

Metabolic studies of human pluripotent stem cells (hPSCs) have focused on how the cells produce energy through the catabolic pathway. The less-studied anabolic pathway, by which hPSCs expend energy in the form of adenosine triphosphate (ATP), is not yet fully understood. Compared to fully differentiated somatic cells, hPSCs undergo significant changes not only in their gene expression but also in their production and/or expenditure of ATP. Here, we investigate how hPSCs tightly control their energy homeostasis by studying the main energy-consuming process, mRNA translation. In addition, change of subcellular organelles regarding energy homeostasis has been investigated. Lysosomes are organelles that play an important role in the elimination of unnecessary cellular materials by digestion and in the recycling system of the cell. We have found that hPSCs control their lysosome numbers in part by regulating lysosomal gene/protein expression. Thus, because the levels of mRNA translation rate are lower in hPSCs than in somatic cells, not only the global translational machinery but also the lysosomal recycling machinery is suppressed in hPSCs. Overall, the results of our study suggest that hPSCs reprogram gene expression and signaling to regulate energy-consuming processes and energy-controlling organelles.

Coronavirus disease 2019 (COVID-19) is causing disruptions in the global social system. Japanese children and adolescents have had their schools closed, government-mandated activity restrictions imposed, and interactions outside the home reduced. These restrictions can have a considerable psychological impact on children and adolescents. This review aims to describe the impacts of COVID-19 pandemic on physical activity and psychological status of this population. The review was conducted by searching PubMed for information on the impact of COVID-19-related activity restrictions on children and adolescents. The search identified 11 articles, three of which contained data on anxiety and psychological problems due to physical inactivity. Next, a PubMed search was conducted about physical activity and psychological status in children and adolescents under psychological stress. The search identified 368 articles, 28 of which were included in the review. For children, data that revealed a correlation between physical activity and psychological health and sedentary time leading to mood disorders were included. For adolescents, there were nine studies that reported a correlation between physical activity and psychological health and four studies that reported no correlation between physical activity and psychological health. Of the studies that reported a correlation, seven reported that physical activity improves psychological health. The impact of psychologically stressful situations such as COVID-19 on children and adolescents has been experienced worldwide. Physical activity has been correlated with psychological health, and it may improve psychological status; physical activity should be recommended to better support the psychological health of children and adolescents under the influence of COVID-19.

Abcg2/Bcrp and Abcb1a/Pgp are xenobiotic efflux transporters limiting substrate permeability in the gastrointestinal system and brain, and increasing renal and hepatic drug clearance. The systemic impact of Bcrp and Pgp ablation on metabolic homeostasis of endogenous substrates is incompletely understood. We performed untargeted metabolomics of cerebrospinal fluid (CSF) and plasma, transcriptomics of brain, liver and kidney from male Sprague Dawley rats (WT) and Bcrp/Pgp double knock-out (dKO) rats, and integrated metabolomic/transcriptomic analysis to identify putative substrates and perturbations in canonical metabolic pathways. A predictive Bayesian machine learning model was used to predict in silico those metabolites with greater substrate-like features for either transporters. The CSF and plasma levels of 169 metabolites, nutrients, signaling molecules, antioxidants and lipids were significantly altered in dKO rats, compared to WT rats. These metabolite changes suggested alterations in histidine, branched chain amino acid, purine and pyrimidine metabolism in the dKO rats. Levels of methylated and sulfated metabolites and some primary bile acids were increased in dKO CSF or plasma. Elevated uric acid levels appeared to be a primary driver of changes in purine and pyrimidine biosynthesis. Alterations in Bcrp/Pgp dKO CSF levels of antioxidants, precursors of neurotransmitters, and uric acid suggests the transporters may contribute to the regulation of a healthy central nervous system in rats. Microbiome-generated metabolites were found to be elevated in dKO rat plasma and CSF. The altered dKO metabolome appeared to cause compensatory transcriptional change in urate biosynthesis and response to lipopolysaccharide in brain, oxidation-reduction processes and response to oxidative stress and porphyrin biosynthesis in kidney, and circadian rhythm genes in liver. These findings present insight into endogenous functions of Bcrp and Pgp, the impact that transporter substrates, inhibitors or polymorphisms may have on metabolism, how transporter inhibition could rewire drug sensitivity indirectly through metabolic changes, and identify functional Bcrp biomarkers.

Background Cognitive deficits such as working memory (WM) impairment are core features of schizophrenia. One candidate marker for the integrity of synaptic neurotransmission necessary for cognitive processes is glutamate. It is frequently postulated that antipsychotic medication possibly alters functional mechanisms in the living brain. We tested in vivo for group differences in activation of the dorsolateral prefrontal cortex (DLPFC) during WM performance and the association with glutamate concentration in DLPFC depending on medication status. Methods A total of 90 subjects (35 control subjects, 36 medicated patients, and 19 unmedicated patients) contributed magnetic resonance spectroscopy data. We estimated glutamate in left DLPFC. Subjects performed an n-back WM task (2-back vs. 0-back) during functional magnetic resonance imaging, and local activation in left DLPFC was measured. For analysis of association with medication status, we calculated linear regression models including an interaction effect with group. Results Medicated and unmedicated patients with schizophrenia showed impaired performance. We found significantly reduced WM activation in left DLPFC in medicated patients and a trendwise reduction in unmedicated patients as compared with control subjects. We found no group difference in local glutamate concentration. However, we found differential effects of medication status on the association between local glutamate concentration and WM activation in left DLPFC, with a positive association in unmedicated patients but not in medicated patients. Conclusions We provide evidence that WM-dependent activation is associated with glutamate concentration in unmedicated patients with schizophrenia. Our finding points to putative allostatic changes that affect the functioning of the brain and might be altered through medication.

Infected or damaged tissues release multiple &ldquo, alert&rdquo, molecules such as alarmins and damage-associated molecular patterns (DAMPs) that are recognized by innate immune receptors, and induce tissue inflammation, regeneration, and repair. Recently, an extract from inflamed rabbit skin inoculated with vaccinia virus (Neurotropin&reg, NTP) was found to induce infarct tolerance in mice receiving permanent ischemic attack to the middle cerebral artery. Likewise, we report herein that NTP prevented the neurite retraction in PC12 cells by nerve growth factor (NGF) deprivation. This effect was accompanied by interaction of Fyn with high-affinity NGF receptor TrkA. Sucrose density gradient subcellular fractionation of NTP-treated cells showed heretofore unidentified membrane fractions with a high-buoyant density containing Trk, B subunit of cholera toxin-bound ganglioside, flotillin-1 and Fyn. Additionally, these new membrane fractions also contained Toll-like receptor 4 (TLR4). Inhibition of TLR4 function by TAK-242 prevented the formation of these unidentified membrane fractions and suppressed neuroprotection by NTP. These observations indicate that NTP controls TrkA-mediated signaling through the formation of clusters of new membrane microdomains, thus providing a platform for crosstalk between neurotrophic and innate immune receptors. Neuroprotective mechanisms through the interaction with innate immune systems may provide novel mechanism for neuroprotection.

Extranodal natural killer/T-cell lymphoma (ENK/TCL) is most often in the nose or the nasopharynx but can present elsewhere. We report a rare case of ENK/TCL that presented as swelling of an upper eyelid without ocular involvement. A 76-year-old man visited our hospital with a swollen lesion of the left upper eyelid which had appeared 2 months earlier. A biopsy of the upper eyelid revealed slight perivascular and periadnexal infiltration of mononuclear cells with dermal edema. Treatment with oral prednisolone at a dosage of 20 mg/day decreased the eyelid swelling. However, 5 months later, exacerbation of the swelling and nasal congestion were observed. A second biopsy of the upper eyelid revealed a diffuse dermal infiltrate composed of mononuclear cells with an angiocentic growth pattern. Immunohistochemical studies and in situ hybridization showed natural killer-lineage antigens (CD56, granzyme B, and T-cell intracellular antigen 1) with expression of Epstein-Barr virus. These findings lead to the diagnosis of ENK/TCL. We treated the patient with radiation therapy (50 Gy) and 3 courses of a regimen including dexamethasone, carboplatin, etoposide, and ifosphamide. This case suggests that ENK/TCL can present with swelling of an upper eyelid as the primary sign of the skin lesion. Swelling of an upper eyelid should be considered in the differential diagnosis of ENK/TCL.

Recent findings have discovered how insufficiency of ATP-binding cassette (ABC) transporter, ABCB6, can negatively impact human health. These advances were made possible by, first, finding that ABCB6 deficiency was the genetic basis for some severe transfusion reactions and by, second, determining that functionally impaired ABCB6 variants enhanced the severity of porphyria, i.e., diseases associated with defects in heme synthesis. ABCB6 is a broad-spectrum porphyrin transporter that is capable of both exporting and importing heme and its precursors across the plasma membrane and outer mitochondrial membrane, respectively. Biochemical studies have demonstrated that while ABCB6 influences the antioxidant system by reducing the levels of reactive oxygen species, the exact mechanism is currently unknown, though effects on heme synthesis are likely. Furthermore, it is unknown what biochemical or cellular signals determine where ABCB6 localizes in the cell. This review highlights the major recent findings on ABCB6 and focuses on details of its structure, mechanism, transport, contributions to cellular stress, and current clinical implications.

This article focuses on rituals in the wake of a disaster, particularly those rituals that concern the dead. Previous studies have paid little attention to such rituals, which have developed and evolved over a long period of time. A diachronic case study of the Nagasaki atomic bomb memorial ceremony shows that memorial rituals gradually shift their attention from the dead to the living. The characteristics observed in this ceremony that orient towards the living can be distinguished from folk rituals, whose central object is to appease or comfort the dead, and also from political rituals, whose aim is to honor the dead and acknowledge the tragic past within a political framework. In addition to economic as well as political factors, the broadcasting of the Nagasaki ceremony on television is instrumental in the changes in these rites and the inclusion of the third-person plural subject: the “we”, appears to be vital in apprehending the experience of violent death. Relying on historical materials, photographs, and data collected by participatory observation and interviews, this article aims to show how people use symbolic practices to make meaning out of violent death.

The increased heme biosynthesis long observed in leukemia was previously of unknown significance. Heme, synthesized from porphyrin precursors, plays a central role in oxygen metabolism and mitochondrial function, yet little is known about its role in leukemogenesis. Here, we show increased expression of heme biosynthetic genes, including UROD, only in pediatric AML samples that have high MYCN expression. High expression of both UROD and MYCN predicts poor overall survival and unfavorable outcomes in adult AML. Murine leukemic progenitors derived from hematopoietic progenitor cells (HPCs) overexpressing a MYCN cDNA (MYCN-HPCs) require heme/porphyrin biosynthesis, accompanied by increased oxygen consumption, to fully engage in self-renewal and oncogenic transformation. Blocking heme biosynthesis reduced mitochondrial oxygen consumption and markedly suppressed self-renewal. Leukemic progenitors rely on balanced production of heme and heme intermediates, the porphyrins. Porphyrin homeostasis is required because absence of the porphyrin exporter, ABCG2, increased death of leukemic progenitors in vitro and prolonged the survival of mice transplanted with Abcg2-KO MYCN-HPCs. Pediatric AML patients with elevated MYCN mRNA display strong activation of TP53 target genes. Abcg2-KO MYCN-HPCs were rescued from porphyrin toxicity by p53 loss. This vulnerability was exploited to show that treatment with a porphyrin precursor, coupled with the absence of ABCG2, blocked MYCN-driven leukemogenesis in vivo, thereby demonstrating that porphyrin homeostasis is a pathway crucial to MYCN leukemogenesis.

Cognitive deficits like working memory impairment in schizophrenia are of great importance for clinical outcome, but the underlying neurobiology is not fully understood. During working memory (WM) altered connectivity patterns in the fronto-parietal network are present in patients suffering from schizophrenia [1–3]. One candidate biochemical marker for the integrity of connectivity is glutamate [4]. Here we tested for group differences in fronto-parietal connectivity and it’s relation to possible glutamatergic influences. During a functional magnetic resonance imaging (fMRI) scan, a sample of 42 medicated patients (SZ) and 41 age and gender matched healthy controls (HC) were asked to perform a numeric n-back working memory task, which consisted of two conditions “2-back” and “0-back”. FMRI was conducted on a 3T Siemens Trio scanner with a 12 channel head coil using gradient-echo echo-planar imaging. Data were further preprocessed using the statistical parametric mapping (SPM 8; Welcome Department of Imaging Neuroscience, London, UK; htt://www.fil.ion.ucl.ac.uk/spm) in MATLAB 2009b. We performed dynamic causal modeling [5] (DCM) on a model space comprising regions of interest for a visual input, parietal (PC) and dorsolateral prefrontal cortex (DLPFC). We calculated Bayesian model averages to obtain weighted connectivity parameters. One-sample t-tests were calculated on parameters for PC->DLPFC and DLPFC->PC connectivity within each group in order to evaluate modulatory effects of working memory on the executive network. Glutamate levels were measured in left DLPFC using magnetic resonance spectroscopy. We used LCmodel (Linear Combination of Model spectra, a commercial spectral fitting package) to estimate local glutamate concentration. Absolute glutamate concentrations were adjusted for grey and white matter volume. We performed group comparisons (two-sample t-test) on connectivity parameters as well as on glutamate levels. Due to non-normality two-sided Spearman correlation analysis were calculated between connectivity parameters and glutamate levels. Working memory dependent connectivity effects (between PC and DLPFC) could be observed in the left hemisphere on backward connections (PC->DLPFC, HC: t=2.77, p=0.008; SZ: t=2.62, p=0.012), whereas no significant working memory effects were present on DLPFC->PC connectivity. We found no group difference in fronto-parietal connectivity parameters and no difference in glutamate levels. Nonetheless numerically controls show higher glutamate levels as compared to patients. To explore possible effects of local Glutamate levels on working memory dependent connectivity, we correlated parameters for PC->DLPFC connectivity (where we found significant working memory dependent effects) with glutamate levels. We found a significant negative association between parieto-frontal connectivity and glutamate in DLPFC in patients (rho=-0.47, p=0.0035). Controls did not show any significant association (rho=-0.12, p=0.53). Comparing correlation coefficients, we found a trend-wise significant difference between groups (z=1.55, p=0.06). Although our data neither showed a difference in connectivity nor in glutamate levels, our findings suggest that glutamate is differentially related to working memory dependent connectivity from parietal to frontal areas in patients as compared to controls.

Although standard induction therapy initially elicits a promising response in the majority of acute myeloid leukemia (AML) patients, the majority relapse. Leukemia stem cells (LSCs) that survive chemotherapy are believed to be responsible for AML relapse. Therefore, new therapies that eliminate LSCs are desperately needed. ONC201 is a TRAIL inducer and the founding member of the imipridone family. It has been shown to induce apoptosis in LSCs (Ishizawa et al, Science Signaling. 2016; 9:ra17). ONC201 was chemically modified to increase the potency and selectivity against cancer cells, resulting in the new analog ONC213. In this study, we investigated the antileukemic activity and the underlying molecular mechanism of ONC213 in preclinical AML models. ONC213 activity in AML cell lines and primary AML patient samples was first tested in vitro. MTT assay results revealed that ONC213 IC50s ranged from 91.7 nM to 2.4 µM in AML cell lines and primary AML patient samples, which are achievable in vivo based on results from a PK study in mice (a single dose of 50 and 100 mg/kg ONC213 resulted in peak plasma concentrations of 3.7 μM and 8 μM, respectively). Annexin V/propidium iodide staining and flow cytometry analysis results showed variable responses for the AML cell lines tested. After 48 h treatment with 500 nM ONC213, striking induction of cell death in MOLM-13 and MV4-11 cells was detected (at least 72% Annexin V+ cells), while THP-1 and U937 cells showed little to no increase in Annexin V+ cells (6-11%). Similar results were obtained in primary AML patient samples. In contrast to the 48 h treatment of THP-1 and U937 cells, increasing the treatment duration to 120 h resulted in greater than 50% Annexin V+ cells, suggesting that a longer exposure time is necessary in some cell lines. In MV4-11 and MOLM-13 cells, initiation of cell death was detected 8 to 12 h post ONC213 treatment. Colony formation assays revealed that ONC213 treatment significantly reduced colony formation capacity of primary AML patient samples to less than 5% compared to vehicle control, while having no significant effect on normal hematopoietic progenitor cells. A primary AML patient sample was treated with or without ONC213 for 48 h, transplanted into NSG mice, and ten weeks later bone marrow was harvested and human CD45+ cells were measured. ONC213 treatment significantly reduced human AML engraftment compared to vehicle control (0.6% vs. 21.3%; p Unlike ONC201, ONC213 treatment of AML cells did not increase the expression of TRAIL. Interestingly, RNAseq results showed that 500 nM ONC213 treatment for 48 h downregulated 33 mRNAs in the oxidative phosphorylation (OXPHOS) pathway, suggesting that ONC213 treatment decreases OXPHOS in AML cells. Thus far, six of the downregulated mRNAs (UQCRQ, SDHA, COX6C, NDUFS5, ATP5D, and NDUFB1) were verified by real-time RT-PCR after both 8 h and 48 h ONC213 treatment. LSCs have been shown to be highly reliant on OXPHOS, while normal hematopoietic stem cells and some bulk AML cells can switch to glycolysis for ATP production during times of OXPHOS inhibition. Thus, ONC213 may kill LSCs through inhibition of OXPHOS. In addition to downregulation of OXPHOS related genes, we found that ONC213 treatment downregulates Mcl-1. Since Mcl-1 mediates resistance to the promising Bcl-2-selective inhibitor ABT-199 (Venetoclax) and inhibition of Bcl-2 impairs OXPHOS, ONC213 would likely synergize with ABT-199 in AML cells. Indeed, combined treatment resulted in striking synergistic induction of apoptosis in both AML cell lines and primary patient samples. Enhanced cell death was detected 8 h post combination treatment in both MOLM-13 and MV4-11 cells. Results from colony formation assays revealed that the combination spares normal hematopoietic progenitor cells. Taken together, ONC213 is active as a single agent and in combination with ABT-199 in AML. Disclosures Allen: Oncoceutics: Employment. Stogniew:Oncoceutics: Employment. Prabhu:Oncoceutics: Employment. Ge:MEI Pharma: Research Funding.

ATP-binding cassette (ABC) transporters confer drug resistance against a wide range of chemotherapeutic agents, including nucleoside and nucleotide based drugs. While nucleoside based drugs have been used for many years in the treatment of solid and hematological malignancies as well as viral and autoimmune diseases, the potential contribution of ABC transporters has only recently been recognized. This neglect is likely because activation of nucleoside derivatives require an initial carrier-mediated uptake step followed by phosphorylation by nucleoside kinases, and defects in uptake or kinase activation were considered the primary mechanisms of nucleoside drug resistance. However, recent studies demonstrate that members of the ABCC transporter subfamily reduce the intracellular concentration of monophosphorylated nucleoside drugs. In addition to the ABCC subfamily members, ABCG2 has been shown to transport nucleoside drugs and nucleoside-monophosphate derivatives of clinically relevant nucleoside drugs such as cytarabine, cladribine, and clofarabine to name a few. This review will discuss ABC transporters and how they interact with other processes affecting the efficacy of nucleoside based drugs.

The mitochondria are key determinants in the life and death of a cell, and abnormalities in mitochondrial function are associated with a number of pathological conditions. Given that many crucial co-factors are generated in mitochondria, including heme and iron–sulfur clusters, it is a reasonable expectation that energy-dependent transporters might facilitate the efficient movement of these molecules through membrane barriers to their next enzymatic steps. The four mitochondrial ABC transporters are ABCB6, ABCB7, ABCB8, and ABCB10. Of these, ABCB6, ABCB7, and ABCB10 have been implicated in processes important to erythroid cells. Mitochondria are also the site of energy production, during which cytotoxic reactive oxygen species are generated. Through modulation of iron and heme biosynthesis, all four mitochondrial ABC transporters have important roles in protecting cells against excessive ROS. In humans, loss-of-function mutations in ABCB7 cause X-linked sideroblastic anemia with ataxia, and several variants that result in loss of ABCB6 at the surface of red cells have been used to identify a new blood group, Lan. ABCB8 has an important role in ischemia. Two of the mammalian mitochondrial transporters, ABCB6 and ABCB7, are closely related to homologs which serve to protect lower organisms from heavy metal toxicity, and mammalian ABCB6 has been demonstrated to provide resistance against some toxic metals, though the mechanism remains unclear. The physiology of mitochondrial transporters and how they contribute to pathological states will be discussed.

The delivery of cancer chemotherapy to treat brain tumors remains a challenge, in part, because of the inherent biological barrier, the blood–brain barrier. While its presence and role as a protector of the normal brain parenchyma has been acknowledged for decades, it is only recently that the important transporter components, expressed in the tightly knit capillary endothelial cells, have been deciphered. These transporters are ATP-binding cassette (ABC) transporters and, so far, the major clinically important ones that functionally contribute to the blood–brain barrier are ABCG2 and ABCB1. A further limitation to cancer therapy of brain tumors or brain metastases is the blood–tumor barrier, where tumors erect a barrier of transporters that further impede drug entry. The expression and regulation of these two transporters at these barriers, as well as tumor derived alteration in expression and/or mutation, are likely obstacles to effective therapy.

The ATP-binding cassette (ABC) transporter ABCB6 localizes to the mitochondria, where it imports porphyrins and up-regulates de novo porphyrin synthesis. If ABCB6 also increases the intracellular heme concentration, it may broadly affect the regulation and physiology of cellular hemoproteins. We tested whether the ability of ABCB6 to accelerate de novo porphyrin biosynthesis alters mitochondrial and extramitochondrial heme levels. ABCB6 overexpression increased the quantity of cytosolic heme but did not affect mitochondrial heme levels. We then tested whether the increased extramitochondrial heme would increase the concentration and/or activity of cellular hemoproteins (hemoglobin, catalase, and cytochrome c oxidase). ABCB6 overexpression increased the activity and quantity of hemoproteins found in several subcellular compartments, and reduction of ABCB6 function (by small interfering RNA or knockout) reversed these findings. In complementary studies, suppression of ABCB6 expression sensitized cells to stress induced by peroxide and cyanide, whereas overexpression of ABCB6 protected against both stressors. Our findings show that the ability of ABCB6 to increase cytosolic heme levels produces phenotypic changes in hemoproteins that protect cells from certain stresses. Collectively, these findings have implications for the health and survival of both normal and abnormal cells, which rely on heme for multiple cellular processes. [Cancer Res 2009;69(13):5560–7]

A 64-year-old man with repetitive gastrointestinal bleeding was admitted to our hospital. Colonic artery angiography revealed angiodysplasia as the bleeding site, and echocardiography showed aortic valve stenosis. A decrease in the high molecular weight von Willebrand factor multimers, which are known to play an important role in hemostasis, was observed, and Heyde syndrome was diagnosed. We selected colectomy instead of aortic valve replacement because the patient had undergone two open heart surgeries. Following colectomy, the patient showed a good clinical course without recurrent gastrointestinal bleeding. Colectomy might serve as a therapeutic option for Heyde syndrome after the precise site of angiodysplasia is detected by angiography.