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Ramcharan Singh Angom,1,* Jian Zhu,1,2,* Alexander TH Wu,3 Maryam Rachmawati Sumitra,4 Victoria Pham,1 Shamit Dutta,1 Enfeng Wang,1 Vijay Sagar Madamsetty,1 Gabriel D Perez-Cordero,1 Hsu-Shan Huang,4 Debabrata Mukhopadhyay,1 Ying Wang5,6 1Department of Biochemistry and Molecular Biology, College of Medicine and Science, Mayo Clinic, Jacksonville, FL, 32224, USA; 2Department of Cardiology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui, 233004, People’s Republic of China; 3The Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan; 4Graduate Institute for Cancer Biology & Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, 110, Taiwan; 5Department of Cardiovascular Medicine, College of Medicine and Science, Mayo Clinic, Rochester, MN, USA; 6Department of Biochemistry and Molecular Biology, College of Medicine and Science, Mayo Clinic, Rochester, MN, 55905, USA*These authors contributed equally to this workCorrespondence: Ying WangDepartment of Cardiovascular Medicine, Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine and Science, 200 1st ST SW, Rochester, MN, 55905, USAEmail wang.ying@mayo.eduObjective: Endothelial cell (EC) activation facilitates leukocyte adhesion to vascular walls, which is implicated in a variety of cardiovascular diseases and is a target for prevention and treatment. Despite the development of anti-inflammatory medications, cost-effective therapies with significant anti-inflammatory effects and lower organ toxicity remain elusive. The goal of this study is to identify novel synthetic compounds that inhibit EC inflammatory response with minimal organ toxicity.Methods and Results: In this study, we discovered LCC-09, a salicylanilide derivative consisting of the functional fragment of magnolol, 2,4-difluorophenyl, and paeonol moiety of salicylate, as a novel anti-inflammatory compound in cultured ECs and zebrafish model. LCC-09 was shown to inhibit pro-inflammatory cytokine tumor necrosis factor-α (TNFα)-induced expression of adhesion molecules and inflammatory cytokines, leading to reduced leukocyte adhesion to ECs. Mechanistically, LCC-09 inhibits the phosphorylation of signal transducer and activator of transcription 1 (STAT1), TNFα-induced degradation of NF-κ-B Inhibitor-α (IκBα) and phosphorylation of NFκB p65, resulting in reduced NFκB transactivation activity and binding to E-selectin promoter. Additionally, LCC-09 attenuated TNFα-induced generation of reactive oxygen species in ECs. Molecular docking models suggest the binding of LCC-09 to NFκB essential modulator (NEMO) and Janus tyrosine kinase (JAK) may lead to dual inhibition of NFκB and STAT1. Furthermore, the anti-inflammatory effect of LCC-09 was validated in the lipopolysaccharides (LPS)-induced inflammation model in zebrafish. Our results demonstrated that LCC-09 significantly reduced the LPS-induced leukocyte recruitment and mortality of zebrafish embryos. Finally, LCC-09 was administered to cultured ECs and zebrafish embryos and showed minimal toxicities.Conclusion: Our results support that LCC-09 inhibits EC inflammatory response but does not elicit significant toxicity.Keywords: endothelial cells, inflammation, salicylanilide derivative, tumor necrosis factor-α, lipopolysaccharides, toxicity

The organization of structure and function of cardiac chambers in vertebrates is defined by chamber-specific distinct gene expression. This peculiarity and uniqueness of the genetic signatures demonstrates functional resolution attributed to the different chambers of the heart. Altered expression of the cardiac chamber genes can lead to individual chamber related dysfunctions and disease patho-physiologies. Information on transcriptional repertoire of cardiac compartments is important to understand the spectrum of chamber specific anomalies. We have carried out a genome wide transcriptome profiling study of the three cardiac chambers in the zebrafish heart using RNA sequencing. We have captured the gene expression patterns of 13,396 protein coding genes in the three cardiac chambers-atrium, ventricle and bulbus arteriosus. Of these, 7,260 known protein coding genes are highly expressed (≥10 FPKM) in the zebrafish heart. Thus, this study represents nearly an all-inclusive information on the zebrafish cardiac transcriptome. In this study, a total of 96 differentially expressed genes across the three cardiac chambers in zebrafish were identified. The atrium, ventricle and bulbus arteriosus displayed 20, 32 and 44 uniquely expressing genes respectively. We validated the expression of predicted chamber-restricted genes using independent semi-quantitative and qualitative experimental techniques. In addition, we identified 23 putative novel protein coding genes that are specifically restricted to the ventricle and not in the atrium or bulbus arteriosus. In our knowledge, these 23 novel genes have either not been investigated in detail or are sparsely studied. The transcriptome identified in this study includes 68 differentially expressing zebrafish cardiac chamber genes that have a human ortholog. We also carried out spatiotemporal gene expression profiling of the 96 differentially expressed genes throughout the three cardiac chambers in 11 developmental stages and 6 tissue types of zebrafish. We hypothesize that clustering the differentially expressed genes with both known and unknown functions will deliver detailed insights on fundamental gene networks that are important for the development and specification of the cardiac chambers. It is also postulated that this transcriptome atlas will help utilize zebrafish in a better way as a model for studying cardiac development and to explore functional role of gene networks in cardiac disease pathogenesis.

Circular RNAs are a new addition to the growing list of diverse species of RNAs that are formed by covalent linked 3' and 5' end forming a closed loop structure. Circular RNAs are characteristically resistant to exonuclease treatment and are relatively stable to linear transcripts. Circular RNAs are formed by alternate splicing mechanism but do not follow the canonical order of exons. Backsplice junctions are unique to circRNAs. CircRNAs are shown to possess potential to act as miRNA sponges and control transcription of mRNAs. CircRNAs are also reported as biomarkers for the disease like Alzheimer's, Parkinson's and cancer. A huge number of circRNA transcripts have been identified in model organisms including C.elegans, mouse, Drosophila as well as human. But there are no circular RNAs reported in zebrafish that is a very good model to study developmental stages, cardiovascular and blood-related disorders. In order to use zebrafish as a model organism and study the role of circRNAs in disease, we have used in-house generated RNA-sequencing data for five tissues including blood, brain, muscle, gills and heart. We discarded the reads mapped contiguously and full length over reference genome and identified back-splice junctions for putative circRNA transcripts. We identified a total of 3428 circRNA junctions out of which 78% were tissue specific. We validated 22 selected candidates for 5 tissues based on literature significance. We quantitatively analysed 5 tissue-enriched candidates using Real-time PCR. We also observed that major proportion of circRNAs is originating from protein coding loci. These circRNAs could be used to further study their role in hematopoietic and cardiovascular diseases.

MicroRNAs are a well-studied class of non-coding RNA and are known to regulate developmental processes in eukaryotes. Their role in key biological processes such as vasculature development has attracted interest. However, a comprehensive understanding of molecular regulation of angiogenesis and vascular integrity during development remains less explored. Here we identified miRNAs involved in the development and maintenance of vasculature in zebrafish embryos using a reverse genetics approach. Using a combination of bioinformatics predictions and literature based evidences we mined over 701 Human and 329 Zebrafish miRNAs to derive a list of 29 miRNAs targeting vascular specific genes in zebrafish. We shortlisted eight miRNAs and investigated their potential role in regulating vascular development in zebrafish transgenic model. In this screen we identified three miRNAs, namely miR-1, miR-144 and miR-142a-3p that have the potential to influence vascular development in zebrafish. We show that miR-142a-3p mediates vascular integrity and developmental angiogenesis in vivo. Overexpression of miR-142a-3p results in loss of vascular integrity, hemorrhage and vascular remodeling during zebrafish embryonic development, while loss of function of miR-142a-3p causes abnormal vascular remodeling. MiR-142a-3p functions in part by directly repressing cdh5 (VE-cadherin). The vascular abnormalities that results from modulation of miR-142a-3p are reminiscent of cdh5 perturbation in zebrafish embryos. We also demonstrate that the action of miR-142a on cdh5 is potentially regulated by Lmo2, an important transcription factor, known for its role in vasculature development. The miR142a-3p mediated control of cdh5 constitutes an additional layer of regulation for maintaining vascular integrity and developmental angiogenesis. These findings have implications in development, wound repair and tumor growth.

Background: The survival rates for children and adolescents with osteosarcoma in low-income countries are poor. Insufficient data regarding the challenges of managing osteosarcoma in resource-limited settings has been published. We evaluated the treatment of osteosarcoma in children and adolescents with the aim of improving the health system and management outcomes., Methods: We sourced data on children under 18 years treated for osteosarcoma at the Uganda Cancer Institute between January 2016 and December 2020. Descriptive statistics and Kaplan-Meier survival analysis were used., Results: Seventy-four osteosarcoma cases were identified, with a median age of 13 years (IQR 9.8-15). Referrals were made after a median of 28 days (range 1-147). Before appropriate referral, more than a quarter (26%) had undergone invasive procedures that could compromise tumour integrity and outcome. Half (50%) of the patients had metastatic disease at diagnosis, primarily to the lungs (n = 43; 92%). Only 14 (33%) patients received neoadjuvant chemotherapy. Forty-three (58.1%) patients underwent limb amputation surgery, including 25 localized tumours and 18 patients with distant metastatic disease. No metastatectomies were performed. Adjuvant chemotherapy was delayed for longer than 21 days in 26 (61%) patients. No pathology reports described the status of resection margins or the degree of chemotherapy-induced necrosis. Twenty-six (35%) patients abandoned treatment, mainly due to pending radical surgery (n = 18/26; 69%). Only 18% (n = 13) were still alive; 46% (n = 34) had died; and 37% (n = 27) had an unknown status. The median overall survival was 1.1 years, and was significantly negatively affected by disease metastasis, timing of adjuvant therapy, and treatment abandonment., Conclusions: Osteosarcoma outcomes for children and adolescents at the Uganda Cancer Institute are extremely poor. The quality of care can be improved by addressing delayed referrals, high rates of prior manipulative therapy, metastatic disease, treatment abandonment, surgical challenges, and delayed resumption of adjuvant chemotherapy., (© 2024. The Author(s).)

Purpose: Reproductive health (RH) is a critical issue among cancer survivors worldwide. However, in developing countries where RH services for patients with cancer are often lacking, reproductive concerns among adolescent and young adult (AYA) survivors remain uncertain. In this study, we assessed the reproductive concerns of AYA cancer survivors in a resource-limited context of Uganda. Methods: We collected data from AYA cancer survivors at two facilities in Uganda using an interviewer-administered questionnaire. Descriptive statistics were calculated, one-way analysis of variance was used for intergroup comparisons, and multiple regressions were used to test for predictors of reproductive concerns. Results: A total of 110 AYA cancer survivors, with a median age of 20 years (interquartile range [IQR], 18-22), were interviewed. More than half (53.6%) of the respondents were males. The median time since cancer diagnosis was 19 months (IQR, 13.0-35.0). Almost all (91.8%) respondents had a future desire to have children, but only 15.5% received reproductive counseling. The mean total score for the reproductive concern subscales was highest for the fertility concern, followed by the information-seeking and health-related concerns. Reproductive counseling, desire to have children, and respondents' age were the factors influencing reproductive concern. Conclusions: The study shows a strong desire for biological parenthood with very low reproductive counseling among AYA cancer survivors, who remain concerned about their fertility, information needs, and health. This outcome underscores the need to integrate RH services into resource-limited cancer care settings.

Background: Radiation therapy is the standard of care for central nervous system tumours. Despite the success of radiation therapy in reducing tumour mass, irradiation (IR)-induced vasculopathies and neuroinflammation contribute to late-delayed complications, neurodegeneration, and premature ageing in long-term cancer survivors. Mesenchymal stromal cells (MSCs) are adult stem cells that facilitate tissue integrity, homeostasis, and repair. Here, we investigated the potential of the iPSC-derived MSC (iMSC) secretome in immunomodulation and vasculature repair in response to radiation injury utilizing human cell lines., Methods: We generated iPSC-derived iMSC lines and evaluated the potential of their conditioned media (iMSC CM) to treat IR-induced injuries in human monocytes (THP1) and brain vascular endothelial cells (hCMEC/D3). We further assessed factors in the iMSC secretome, their modulation, and the molecular pathways they elicit., Results: Increasing doses of IR disturbed endothelial tube and spheroid formation in hCMEC/D3. When IR-injured hCMEC/D3 (IR ≤ 5 Gy) were treated with iMSC CM, endothelial cell viability, adherence, spheroid compactness, and proangiogenic sprout formation were significantly ameliorated, and IR-induced ROS levels were reduced. iMSC CM augmented tube formation in cocultures of hCMEC/D3 and iMSCs. Consistently, iMSC CM facilitated angiogenesis in a zebrafish model in vivo. Furthermore, iMSC CM suppressed IR-induced NFκB activation, TNF-α release, and ROS production in THP1 cells. Additionally, iMSC CM diminished NF-kB activation in THP1 cells cocultured with irradiated hCMEC/D3, iMSCs, or HMC3 microglial lines. The cytokine array revealed that iMSC CM contains the proangiogenic and immunosuppressive factors MCP1/CCL2, IL6, IL8/CXCL8, ANG (Angiogenin), GROα/CXCL1, and RANTES/CCL5. Common promoter regulatory elements were enriched in TF-binding motifs such as androgen receptor (ANDR) and GATA2. hCMEC/D3 phosphokinome profiling revealed increased expression of pro-survival factors, the PI3K/AKT/mTOR modulator PRAS40 and β-catenin in response to CM. The transcriptome analysis revealed increased expression of GATA2 in iMSCs and the enrichment of pathways involved in RNA metabolism, translation, mitochondrial respiration, DNA damage repair, and neurodevelopment., Conclusions: The iMSC secretome is a comodulated composite of proangiogenic and immunosuppressive factors that has the potential to alleviate radiation-induced vascular endothelial cell damage and immune activation., (© 2024. The Author(s).)

Background: CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) technology-mediated genome editing has significantly improved the targeted inactivation of genes in vitro and in vivo in many organisms. Neuropilins play crucial roles in zebrafish heart regeneration, heart failure in mice, and electrical remodeling after myocardial infarction in rats. But the cell-specific functions of nrp1 have not been described before. In this study, we have investigated the role of nrp1 isoforms, including nrp1a and nrp1b , in cardiomyocytes during cardiac injury and regeneration in adult zebrafish hearts., Methods: In this study, we have reported a novel CRISPR-based vector system for conditional tissue-specific gene ablation in zebrafish. Specifically, the cardiac-specific cmlc2 promoter drives Cas9 expression to silence the nrp1 gene in cardiomyocytes in a heat-shock inducible manner. This vector system establishes a unique tool to regulate the gene knockout in both the developmental and adult stages and hence widens the possibility of loss-of-function studies in zebrafish at different stages of development and adulthood. Using this approach, we investigated the role of neuropilin isoforms nrp1a and nrp1b in response to cardiac injury and regeneration in adult zebrafish hearts., Results: We observed that both the isoforms ( nrp1a and nrp1b ) are upregulated after the cryoinjury. Interestingly, the nrp1b knockout significantly delayed heart regeneration and impaired cardiac function in the adult zebrafish after cryoinjury, demonstrated by reduced heart rate, ejection fractions, and fractional shortening. In addition, we show that the knockdown of nrp1b but not nrp1a induces activation of the cardiac remodeling genes in response to cryoinjury., Conclusions: To our knowledge, this study is novel where we have reported a heat-shock-mediated conditional knockdown of nrp1a and nrp1b isoforms using CRISPR/Cas9 technology in the cardiomyocyte in zebrafish and furthermore have identified a crucial role for the nrp1b isoform in zebrafish cardiac remodeling and eventually heart function in response to injury., Competing Interests: Disclosures None.

Brain tumors are the most common solid tumors in children and a leading cause of cancer-related mortality in children worldwide. Data on the epidemiology and management of pediatric brain tumors in Uganda are limited. We aimed to assess the clinicopathological profile and management of pediatric brain tumors at the national oncology center in Uganda since the inception of weekly multidisciplinary meetings. Records of children younger than19 years diagnosed with primary brain tumors at Uganda Cancer Institute between 2017 and 2021 were retrospectively reviewed. Patient and tumor characteristics were collected with multidisciplinary team management treatment plans for analysis. There were 35 patients evaluated, most of whom were males (57.1%). Craniopharyngioma (n = 9, 25.7%) was the most common brain tumor, followed by astrocytoma (n = 5, 14.2%) and medulloblastoma (n = 4, 11.4%). Management included surgical resection in 28.5% of patients, chemotherapy (28.6%), radiotherapy (17.1%) and palliative care (20.0%). Over the last five years, there were increasing trends in the number of cases discussed in the multidisciplinary team and the number for whom the multidisciplinary management decisions were implemented. The majority (n = 18, 51.4%) of the children with brain tumors were alive and active in care, 34.2% abandoned treatment/lost to follow-up, and 8.6% died. The relative distribution of pediatric brain tumors types in Uganda Cancer Institute differs slightly from international reports, and there has been a notable increase in the number of cases over the years. Implementing multidisciplinary management decisions benefited patients and decreased abandonment and patient loss to follow-up.

Limited survival data for the six Global Initiative for Childhood Cancer (GICC) priority cancers are available in Africa. Management of pediatric malignancies in Africa is challenging due to lack of resources, setting-specific comorbidities, high rates of late presentation and treatment abandonment. Reporting of outcome data is problematic due to the lack of registries. With the aim of evaluating the feasibility of baseline outcomes for the six index cancers, we present a descriptive analysis of respective survival rates in Africa. The survival rates were between 18% (lower middle-income countries) to 82.3% (upper middle-income countries) for acute lymphoblastic leukemia, between 26.9% (low-income countries) to 77.9% (upper middle-income countries) for nephroblastoma, between 23% (low-income countries) to 100% (upper middle-income countries), for retinoblastoma, 45% (low-income countries) to 95% (upper middle-income countries) for Hodgkin lymphoma and 28% (low-income countries) to 76% (upper middle-income countries) for Burkitt lymphoma. Solutions to improve survival rates and reported outcomes include establishing and funding sustainable registries, training and to actively include all countries in consortia from different African regions.HighlightsContinental differences in childhood cancer management such lack of resources, setting-specific comorbidities, high rates of late presentation and treatment abandonment, present challenges to the achievement of Global Initiative for Childhood Cancer goals.The available data registries do not adequately inform on the true incidences and outcomes of childhood cancers in Africa.The pathophysiology of some childhood cancers in Africa are associated with high-risk prognostic factors.Outcomes can be improved by greater regional collaboration to manage childhood cancer based on local resources and tumor characteristics.Some individual countries have reached the Global Initiative for Childhood Cancer goals for single cancers and it should be possible for more African countries to follow suit.

Background: There have hardly been any reported cases of children presenting with Kaposi sarcoma as a second malignancy following treatment for acute lymphoblastic leukemia outside a transplant setting., Case Presentation: We report a case of a 5-year-old boy of Bantu origin, which, to our knowledge, could be only the second reported case of oral-visceral Kaposi sarcoma after acute lymphoblastic leukemia treatment. The patient presented with a 1-month history of progressive, non-painful, soft tissue oral mass, 1 month after completing treatment for high-risk acute lymphoblastic leukemia. He was successfully treated for Kaposi sarcoma on a two-drug regimen (bleomycin and vincristine) with good clinical response., Conclusion: Visceral Kaposi sarcoma as a second malignancy may occur after pediatric acute lymphoblastic leukemia treatment, but its rarity makes it unlikely to raise suspicion among clinicians, thus precluding early diagnosis and treatment. We recommend routine evaluation for Kaposi sarcoma lesions in children undergoing long-term surveillance following treatment for childhood acute leukemia., (© 2022. The Author(s).)

Aggregated amyloid β (Aβ) peptides in the Alzheimer's disease (AD) brain are hypothesized to trigger several downstream pathologies, including cerebrovascular dysfunction. Previous studies have shown that Aβ peptides can have antiangiogenic properties, which may contribute to vascular dysfunction in the early stages of the disease process. We have generated data showing that brain endothelial cells (ECs) exposed to toxic Aβ1-42 oligomers can readily enter a senescence phenotype. To determine the effect of Aβ oligomers on brain ECs, we treated early passaged human brain microvascular ECs and HUVECs with high MW Aβ1-42 oligomers (5 µM, for 72 h). For controls, we used no peptide treatment, 5 µM Aβ1-42 monomers, and 5 µM Aβ1-42 fibrils, respectively. Brain ECs treated with Aβ1-42 oligomers showed increased senescence-associated β-galactosidase staining and increased senescence-associated p21/p53 expression. Treatment with either Aβ1-42 monomer or Aβ1-42 fibrils did not induce senescence in this assay. We then measured vascular endothelial growth factor receptor (VEGFR) expression in the Aβ1-42 oligomer-treated ECs, and these cells showed significantly increased VEGFR-1 expression and decreased VEGFR-2 levels. Overexpression of VEGFR-1 in brain ECs readily induced senescence, suggesting a direct role of VEGFR-1 signaling events in this paradigm. More importantly, small interfering RNA-mediated knockdown of VEGFR-1 expression in brain ECs was able to prevent up-regulation of p21 protein expression and significantly reduced induction of senescence following Aβ1-42 oligomer treatment. Our studies show that exposure to Aβ1-42 oligomers may impair vascular functions by altering VEGFR-1 expression and causing ECs to enter a senescent phenotype. Altered VEGFR expression has been documented in brains of AD patients and suggests that this pathway may play a role in AD disease pathogenesis. These studies suggest that modulating VEGFR-1 expression and signaling events could potentially prevent senescence and rejuvenate EC functions, and provides us with a novel target to pursue for prevention and treatment of cerebrovascular dysfunction in AD.-Angom, R. S., Wang, Y., Wang, E., Pal, K., Bhattacharya, S., Watzlawik, J. O., Rosenberry, T. L., Das, P., Mukhopadhyay, D. VEGF receptor-1 modulates amyloid β 1-42 oligomer-induced senescence in brain endothelial cells.

Background: Little data are available on bacterial contamination (BC) of platelet units or acute transfusion reactions to platelet transfusions (PTs) in sub-Saharan Africa (SSA)., Study Design and Methods: This prospective, observational study evaluated the rate of BC in whole blood-derived platelet units (WB-PUs), the utility of performing Gram stains to prevent septic reactions, characteristics of patients receiving PTs, and the rate of acute reactions associated with PTs at the Uganda Cancer Institute in Kampala, Uganda. An aliquot of each WB-PU studied was taken to perform Gram stains and culture using the Bactec 9120 instrument. Study participants were monitored for reactions., Results: In total, 337 WB-PUs were evaluated for BC, of which 323 units were transfused in 151 transfusion episodes to 50 patients. The frequency of BC ranged from 0.3% to 2.1% (according to criteria used to define BC). The Gram stain had high specificity (99.1%) but low sensitivity to detect units with BC. The median platelet count before PT was 10,900 cells/µL (interquartile range, 6000-18,900 cells/µL). Overall, 78% of PTs were given to patients with no bleeding. Acute reactions occurred in 11 transfusion episodes, involving 13 WB-PUs, for a rate of 7.3% (95% confidence interval, 3.7%-12.7%) per transfusion episode. All recipients of units with positive bacterial cultures were receiving antibiotics at the time of transfusion; none experienced a reaction., Conclusions: The rate of BC observed in this study is lower than previously reported in SSA, but still remains a safety issue. Because Gram staining appears to be an ineffective screening tool, alternate methods should be explored to prevent transfusing bacterially contaminated platelets in sub-Saharan Africa., (© 2016 AABB.)