scholarly journals ATRT-32. GENOME-WIDE CRISPR AND SMALL-MOLECULE SCREENS UNCOVER TARGETABLE DEPENDENCIES IN AT/RTs

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii282-iii282
Author(s):  
Daniel Merk ◽  
Sophie Hirsch ◽  
Bianca Walter ◽  
Lara Häusser ◽  
Nicole Persky ◽  
...  
Keyword(s):  
Brain Tumors ◽  
Small Molecule ◽  
Molecular Mechanisms ◽  
Young Patients ◽  
Chemical Library ◽  
Genome Wide ◽  
Starting Point ◽  
Drug Assays ◽  
Tumor Entity ◽  
Rhabdoid Tumors

Abstract Brain tumors are the leading cause of cancer-related deaths in children and adolescents. Embryonal brain tumors are a group of high-grade neoplasms which primarily affect young patients, and atypical teratoid rhabdoid tumors (AT/RTs) are the second most common type of tumor within this group. In spite of intensive research efforts and the knowledge of molecular mechanisms driving subgroup-specific heterogeneity within ATRTs, survival estimates stay relatively low as compared to other tumor entities with a median survival of around 17 months. More efficacious and durable therapies are urgently needed to improve the situation of patients. We here used a combination of genome-wide CRISPR dependency screens and small-molecule drug assays to identify genetic vulnerabilities and novel therapeutic targets for this tumor entity. Here, we successfully generated a chemical library that shows preferential activity in AT/RT cell lines, thereby validating our CRISPR approach to identify tumor-specific vulnerabilities. Of note, none of the identified dependencies seemed to be subgroup-specific, suggesting that targets identified here can be used as pan-AT/RT therapeutic avenues. Among others, these include inhibition of EGF signaling and CDK4/6. Our data provide a comprehensive map of dependencies for AT/RTs which will serve as a starting point in the development of targeted therapies for this tumor entity.

EXTH-69. FUNCTIONAL GENOMICS UNCOVER GENETIC DEPENDENCIES IN ATRTS

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi179-vi179
Author(s):  
Daniel Merk ◽  
Sophie Hirsch ◽  
Foteini Tsiami ◽  
Bianca Walter ◽  
Lara Haeusser ◽  
...  
Keyword(s):  
Brain Tumors ◽  
Small Molecule ◽  
Human Cancer ◽  
Human Cancer Cell Lines ◽  
Drug Assays ◽  
Atypical Teratoid ◽  
Embryonal Brain ◽  
Atypical Teratoid Rhabdoid Tumors ◽  
Rhabdoid Tumors ◽  
Context Specific

Abstract Brain tumors are the leading cause of cancer-related deaths in children. Embryonal brain tumors including medulloblastoma and atypical teratoid rhabdoid tumors (ATRTs) account for 15% of all primary brain and CNS tumors under the age of 14 years, with ATRTs being most prevalent in infants. Despite intensive research efforts, survival estimates for ATRT patients stay relatively low as compared to other tumor entities with a median survival of around 17 months. We here describe genome-wide CRISPR/Cas9 knockout screens in combination with small-molecule drug assays to identify targetable vulnerabilities in ATRTs. Based on functional genomic screening revealing ATRT context-specific genetic vulnerabilities (n = 671 genes), we successfully generated a small-molecule library that shows preferential activity in ATRT cells as compared to a broad selection of other human cancer cell lines. Of note, none of these drugs differentially affect ATRT cells from distinct molecular subgroups, suggesting that top candidate inhibitors might serve as pan-ATRT therapeutic avenues. CDK4/6 inhibitors, among the most potent drugs in our library, are capable of inhibiting tumor growth due to mutual exclusive dependency of ATRTs on either CDK4 or CDK6. Our approach might serve as a blueprint for fostering the identification of functionally-instructed therapeutic strategies in other incurable diseases beyond ATRT, whose genomic profiles also lack actionable alterations so far.

Identification of early gene expression changes during human Th17 cell differentiation

Blood ◽  
2012 ◽  
Vol 119 (23) ◽  
pp. e151-e160 ◽  
Author(s):  
Soile Tuomela ◽  
Verna Salo ◽  
Subhash K. Tripathi ◽  
Zhi Chen ◽  
Kirsti Laurila ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Differentiation ◽  
Th17 Cell ◽  
Regulatory Networks ◽  
Molecular Mechanisms ◽  
Early Gene ◽  
Th17 Cell Differentiation ◽  
Genome Wide ◽  
Starting Point ◽  
Th17 Differentiation

Abstract Th17 cells play an essential role in the pathogenesis of autoimmune and inflammatory diseases. Most of our current understanding on Th17 cell differentiation relies on studies carried out in mice, whereas the molecular mechanisms controlling human Th17 cell differentiation are less well defined. In this study, we identified gene expression changes characterizing early stages of human Th17 cell differentiation through genome-wide gene expression profiling. CD4+ cells isolated from umbilical cord blood were used to determine detailed kinetics of gene expression after initiation of Th17 differentiation with IL1β, IL6, and TGFβ. The differential expression of selected candidate genes was further validated at protein level and analyzed for specificity in initiation of Th17 compared with initiation of other Th subsets, namely Th1, Th2, and iTreg. This first genome-wide profiling of transcriptomics during the induction of human Th17 differentiation provides a starting point for defining gene regulatory networks and identifying new candidates regulating Th17 differentiation in humans.

scholarly journals Genome-wide CRISPR and small-molecule screens uncover targetable dependencies in ATRT

2020 ◽  
Author(s):  
Daniel J. Merk ◽  
Sophie Hirsch ◽  
Foteini Tsiami ◽  
Bianca Walter ◽  
Lara A. Haeusser ◽  
...  
Keyword(s):  
Small Molecule ◽  
Pediatric Brain Tumors ◽  
Genetic Alterations ◽  
Therapeutic Strategies ◽  
Genome Wide ◽  
Atypical Teratoid ◽  
Atypical Teratoid Rhabdoid Tumors ◽  
Rhabdoid Tumors ◽  
Context Specific ◽  
Pediatric Brain

SummaryAtypical teratoid rhabdoid tumors (ATRT) are incurable high-grade pediatric brain tumors. Concepts for molecular-driven therapies in ATRTs lag behind, mainly due to the absence of actionable genetic alterations. We performed genome-wide CRISPR/Cas9 knockout screens in six human ATRT cell lines and identified a total of 671 context-specific essential genes. Based on these genetic dependencies, we constructed a library of small-molecule inhibitors that we found to preferentially inhibit growth of ATRT cells. CDK4/6 inhibitors, among the most potent drugs in our library, are capable of inhibiting tumor growth due to mutual exclusive dependency of ATRTs on CDK4 or CDK6. These distinct dependencies drive heterogeneity in response to CDK4/6 inhibitors in ATRTs. Our approach might serve as a blueprint for fostering the identification of functionally-instructed therapeutic strategies in other incurable diseases beyond ATRT, whose genomic profiles also lack actionable alterations so far.

scholarly journals A unique small molecule pair controls the plant circadian clock

2020 ◽  
Author(s):  
Takahiro N Uehara ◽  
Saori Takao ◽  
Hiromi Matsuo ◽  
Ami N. Saito ◽  
Eisuke Ota ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Small Molecule ◽  
Molecular Mechanisms ◽  
Response Regulator ◽  
Structure Activity Relationship ◽  
Activity Relationship ◽  
Genetic Redundancy ◽  
Chemical Library ◽  
Structure Activity ◽  
Relationship Study

SummaryCircadian clocks are the biological time keeping systems that coordinate genetic, metabolic, and physiological behaviors with the external day-night cycle. Previous studies have suggested possible molecular mechanisms for the circadian clock in Arabidopsis thaliana (Arabidopsis), but there might be additional mechanisms that have been hidden due to genetic redundancy.A clock reporter line of Arabidopsis was screened against the 10,000 chemicals in the Maybridge Hitfinder10K chemical library, and a structure-activity relationship study of hit compounds was conducted. Clock mutants were treated with two of the small molecules to gain insight into their mode of action.The screening identified 5-(3,4-dichlorophenyl)-1-phenyl-1,7-dihydro-4H-pyrazolo[3,4-d]pyrimidine-4,6(5H)-dione (TU-892) as a period lengthening molecule. From a structure-activity relationship study, we found that a molecule possessing 2,4-dichlorophenyl instead of a 3,4-dichlorophenyl group (TU-923) had period shortening activity. The period shortening activity of TU-923 was reversed to a lengthening activity in double mutants lacking PSEUDO-RESPONSE REGULATOR 9 (PRR9) and PRR7 (prr9-10 prr7-11).Our study provides a unique small molecule pair that regulates the pace of the clock in opposite ways, likely by targeting unknown factors. Small differences at the atomic level can reverse the period tuning activities. PRR9 and PRR7 are essential for the activity of TU-923 in period shortening.

Genome-wide identification and analysis of the GATA transcription factor gene family in Ustilaginoidea virens

Genome ◽  
2019 ◽  
Vol 62 (12) ◽  
pp. 807-816 ◽  
Author(s):  
Mina Yu ◽  
Junjie Yu ◽  
Huijuan Cao ◽  
Mingli Yong ◽  
Yongfeng Liu
Keyword(s):  
Transcription Factors ◽  
Molecular Mechanisms ◽  
Expression Profiles ◽  
Ustilaginoidea Virens ◽  
Genome Wide ◽  
Transcriptional Regulatory ◽  
Starting Point ◽  
Reactive Oxygen Species Stress ◽  
False Smut ◽  
Transcriptional Regulatory Mechanisms

In filamentous fungi, the conserved transcription factors play important roles in multiple cellular and developmental processes. The GATA proteins, a family of GATA-binding zinc finger transcription factors, play diverse functions in fungi. Ustilaginoidea virens is an economically important pathogen-causing rice false smut worldwide. To gain additional insight into the cellular and molecular mechanisms of this pathogen, in this study, we identified and functionally characterized seven GATA proteins from the U. virens genome (UvGATA). Sequences analysis indicated that these GATA proteins are divided into seven clades. The proteins in each clade contained conserved clade-specific sequences and structures, thus leading to the same motif serving different purposes in various contexts. The expression profiles of UvGATA genes at different infection stages and under H2O2 stress were detected. Results showed that the majority of UvGATA genes performed functions at both processes, thereby confirming the roles of these genes in pathogenicity and reactive oxygen species stress tolerance. This study provided an important starting point to further explore the biological functions of UvGATA genes and increased our understanding of their potential transcriptional regulatory mechanisms in U. virens.

Artificial Intelligence for epigenetics: towards personalized medicine

2020 ◽  
Vol 27 ◽  
Author(s):  
Giulia De Riso ◽  
Sergio Cocozza
Keyword(s):  
Biological Sciences ◽  
Artificial Intelligence ◽  
Personalized Medicine ◽  
Molecular Mechanisms ◽  
Genomic Sequence ◽  
Health Care Interventions ◽  
Genome Wide ◽  
Genetic And Environmental Factors ◽  
Opening Up ◽  
Omic Data

: Epigenetics is a field of biological sciences focused on the study of reversible, heritable changes in gene function not due to modifications of the genomic sequence. These changes are the result of a complex cross-talk between several molecular mechanisms, that is in turn orchestrated by genetic and environmental factors. The epigenetic profile captures the unique regulatory landscape and the exposure to environmental stimuli of an individual. It thus constitutes a valuable reservoir of information for personalized medicine, which is aimed at customizing health-care interventions based on the unique characteristics of each individual. Nowadays, the complex milieu of epigenomic marks can be studied at the genome-wide level thanks to massive, highthroughput technologies. This new experimental approach is opening up new and interesting knowledge perspectives. However, the analysis of these complex omic data requires to face important analytic issues. Artificial Intelligence, and in particular Machine Learning, are emerging as powerful resources to decipher epigenomic data. In this review, we will first describe the most used ML approaches in epigenomics. We then will recapitulate some of the recent applications of ML to epigenomic analysis. Finally, we will provide some examples of how the ML approach to epigenetic data can be useful for personalized medicine.

scholarly journals Genetic analysis of amyotrophic lateral sclerosis identifies contributing pathways and cell types

2021 ◽  
Vol 7 (3) ◽  
pp. eabd9036
Author(s):  
Sara Saez-Atienzar ◽  
Sara Bandres-Ciga ◽  
Rebekah G. Langston ◽  
Jonggeol J. Kim ◽  
Shing Wan Choi ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Membrane Trafficking ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Polygenic Risk Score ◽  
Genome Wide ◽  
Genome Wide Data ◽  
Data Driven Approach ◽  
Single Nucleus ◽  
Lateral Sclerosis

Despite the considerable progress in unraveling the genetic causes of amyotrophic lateral sclerosis (ALS), we do not fully understand the molecular mechanisms underlying the disease. We analyzed genome-wide data involving 78,500 individuals using a polygenic risk score approach to identify the biological pathways and cell types involved in ALS. This data-driven approach identified multiple aspects of the biology underlying the disease that resolved into broader themes, namely, neuron projection morphogenesis, membrane trafficking, and signal transduction mediated by ribonucleotides. We also found that genomic risk in ALS maps consistently to GABAergic interneurons and oligodendrocytes, as confirmed in human single-nucleus RNA-seq data. Using two-sample Mendelian randomization, we nominated six differentially expressed genes (ATG16L2, ACSL5, MAP1LC3A, MAPKAPK3, PLXNB2, and SCFD1) within the significant pathways as relevant to ALS. We conclude that the disparate genetic etiologies of this fatal neurological disease converge on a smaller number of final common pathways and cell types.

scholarly journals Identification of 3,4-Dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine Derivatives as Novel Selective Inhibitors of Plasmodium falciparum Dihydroorotate Dehydrogenase

2021 ◽  
Vol 22 (13) ◽  
pp. 7236
Author(s):  
Endah Dwi Hartuti ◽  
Takaya Sakura ◽  
Mohammed S. O. Tagod ◽  
Eri Yoshida ◽  
Xinying Wang ◽  
...  
Keyword(s):  
Drug Target ◽  
De Novo ◽  
Dihydroorotate Dehydrogenase ◽  
Chemical Library ◽  
New Class ◽  
De Novo Biosynthesis ◽  
Starting Point ◽  
Novel Drugs ◽  
Low Toxicity ◽  
Fourth Step

Plasmodium falciparum’s resistance to available antimalarial drugs highlights the need for the development of novel drugs. Pyrimidine de novo biosynthesis is a validated drug target for the prevention and treatment of malaria infection. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the oxidation of dihydroorotate to orotate and utilize ubiquinone as an electron acceptor in the fourth step of pyrimidine de novo biosynthesis. PfDHODH is targeted by the inhibitor DSM265, which binds to a hydrophobic pocket located at the N-terminus where ubiquinone binds, which is known to be structurally divergent from the mammalian orthologue. In this study, we screened 40,400 compounds from the Kyoto University chemical library against recombinant PfDHODH. These studies led to the identification of 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine and its derivatives as a new class of PfDHODH inhibitor. Moreover, the hit compounds identified in this study are selective for PfDHODH without inhibition of the human enzymes. Finally, this new scaffold of PfDHODH inhibitors showed growth inhibition activity against P. falciparum 3D7 with low toxicity to three human cell lines, providing a new starting point for antimalarial drug development.

scholarly journals Genome-Wide Mapping of Histone H3 Lysine 4 Trimethylation (H3K4me3) and Its Involvement in Fatty Acid Biosynthesis in Sunflower Developing Seeds

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 706
Author(s):  
Antonio J. Moreno-Pérez ◽  
Raquel Martins-Noguerol ◽  
Cristina DeAndrés-Gil ◽  
Mónica Venegas-Calerón ◽  
Rosario Sánchez ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Chromatin Remodeling ◽  
Molecular Mechanisms ◽  
Acid Metabolism ◽  
Fatty Acid Biosynthesis ◽  
Acid Synthesis ◽  
Sunflower Seeds ◽  
Acid Biosynthesis ◽  
Functional Regions ◽  
Genome Wide

Histone modifications are of paramount importance during plant development. Investigating chromatin remodeling in developing oilseeds sheds light on the molecular mechanisms controlling fatty acid metabolism and facilitates the identification of new functional regions in oil crop genomes. The present study characterizes the epigenetic modifications H3K4me3 in relationship with the expression of fatty acid-related genes and transcription factors in developing sunflower seeds. Two master transcriptional regulators identified in this analysis, VIV1 (homologous to Arabidopsis ABI3) and FUS3, cooperate in the regulation of WRINKLED 1, a transcriptional factor regulating glycolysis, and fatty acid synthesis in developing oilseeds.

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