Systems Biology

A multiplex method for detection of SARS-CoV-2 variants based on MALDI-TOF mass spectrometry

Mon, 2023-05-01 06:00

Biosaf Health. 2023 Apr;5(2):101-107. doi: 10.1016/j.bsheal.2023.02.003. Epub 2023 Mar 1.

ABSTRACT

The recent outbreak of the coronavirus disease 2019 (COVID-19) pandemic and the continuous evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have highlighted the significance of new detection methods for global monitoring and prevention. Although quantitative reverse transcription PCR (RT-qPCR), the current gold standard for diagnosis, performs excellently in genetic testing, its multiplexing capability is limited because of the signal crosstalk of various fluorophores. Herein, we present a highly efficient platform which combines 17-plex assays with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), enabling the targeting of 14 different mutation sites of the spike gene. Diagnosis using a set of 324 nasopharyngeal swabs or sputum clinical samples with SARS-CoV-2 MS method was identical to that with the RT-qPCR. The detection consistency of mutation sites was 97.9% (47/48) compared to Sanger sequencing without cross-reaction with other respiratory-related pathogens. Therefore, the MS method is highly potent to track and assess SARS-CoV-2 changes in a timely manner, thereby aiding the continuous response to viral variation and prevention of further transmission.

PMID:37123451 | PMC:PMC9977071 | DOI:10.1016/j.bsheal.2023.02.003

Categories: Literature Watch

Bromodomain protein BRD8 regulates cell cycle progression in colorectal cancer cells through a TIP60-independent regulation of the pre-RC complex

Mon, 2023-05-01 06:00

iScience. 2023 Apr 1;26(4):106563. doi: 10.1016/j.isci.2023.106563. eCollection 2023 Apr 21.

ABSTRACT

Bromodomain-containing protein 8 (BRD8) is a subunit of the NuA4/TIP60-histone acetyltransferase complex. Although BRD8 has been considered to act as a co-activator of the complex, its biological role remains to be elucidated. Here, we uncovered that BRD8 accumulates in colorectal cancer cells through the inhibition of ubiquitin-dependent protein degradation by the interaction with MRG domain binding protein. Transcriptome analysis coupled with genome-wide mapping of BRD8-binding sites disclosed that BRD8 transactivates a set of genes independently of TIP60, and that BRD8 regulates the expression of multiple subunits of the pre-replicative complex in concert with the activator protein-1. Depletion of BRD8 induced cell-cycle arrest at the G1 phase and suppressed cell proliferation. We have also shown that the bromodomain of BRD8 is indispensable for not only the interaction with histone H4 or transcriptional regulation but also its own protein stability. These findings highlight the importance of bromodomain as a therapeutic target.

PMID:37123243 | PMC:PMC10139981 | DOI:10.1016/j.isci.2023.106563

Categories: Literature Watch

Kinase-Modulated Bioluminescent Indicators Enable Noninvasive Imaging of Drug Activity in the Brain

Mon, 2023-05-01 06:00

ACS Cent Sci. 2023 Mar 20;9(4):719-732. doi: 10.1021/acscentsci.3c00074. eCollection 2023 Apr 26.

ABSTRACT

Aberrant kinase activity contributes to the pathogenesis of brain cancers, neurodegeneration, and neuropsychiatric diseases, but identifying kinase inhibitors that function in the brain is challenging. Drug levels in blood do not predict efficacy in the brain because the blood-brain barrier prevents entry of most compounds. Rather, assessing kinase inhibition in the brain requires tissue dissection and biochemical analysis, a time-consuming and resource-intensive process. Here, we report kinase-modulated bioluminescent indicators (KiMBIs) for noninvasive longitudinal imaging of drug activity in the brain based on a recently optimized luciferase-luciferin system. We develop an ERK KiMBI to report inhibitors of the Ras-Raf-MEK-ERK pathway, for which no bioluminescent indicators previously existed. ERK KiMBI discriminates between brain-penetrant and nonpenetrant MEK inhibitors, reveals blood-tumor barrier leakiness in xenograft models, and reports MEK inhibitor pharmacodynamics in native brain tissues and intracranial xenografts. Finally, we use ERK KiMBI to screen ERK inhibitors for brain efficacy, identifying temuterkib as a promising brain-active ERK inhibitor, a result not predicted from chemical characteristics alone. Thus, KiMBIs enable the rapid identification and pharmacodynamic characterization of kinase inhibitors suitable for treating brain diseases.

PMID:37122464 | PMC:PMC10141594 | DOI:10.1021/acscentsci.3c00074

Categories: Literature Watch

Batch Correction and Harmonization of -Omics Datasets with a Tunable Median Polish of Ratio

Mon, 2023-05-01 06:00

Front Syst Biol. 2023;3:1092341. doi: 10.3389/fsysb.2023.1092341. Epub 2023 Apr 12.

ABSTRACT

Large scale -omics datasets can provide new insights into normal and disease-related biology when analyzed through a systems biology framework. However, technical artefacts present in most -omics datasets due to variations in sample preparation, batching, platform settings, personnel, and other experimental procedures prevent useful analyses of such data without prior adjustment for these technical factors. Here, we demonstrate a tunable median polish of ratio (TAMPOR) approach for batch effect correction and agglomeration of multiple, multi-batch, site-specific cohorts into a single analyte abundance data matrix that is suitable for systems biology analyses. We illustrate the utility and versatility of TAMPOR through four distinct use cases where the method has been applied to different proteomic datasets, some of which contain a specific defect that must be addressed prior to analysis. We compare quality control metrics and sources of variance before and after application of TAMPOR to show that TAMPOR is effective at removing batch effects and other unwanted sources of variance in -omics data. We also show how TAMPOR can be used to harmonize -omics datasets even when the data are acquired using different analytical approaches. TAMPOR is a powerful and flexible approach for cleaning and harmonization of -omics data prior to downstream systems biology analysis.

PMID:37122388 | PMC:PMC10137904 | DOI:10.3389/fsysb.2023.1092341

Categories: Literature Watch

Carbachol, along with calcium, indicates new strategy in neural differentiation of human adipose tissue-derived mesenchymal stem cells <em>in vitro</em>

Mon, 2023-05-01 06:00

Regen Ther. 2023 Apr 15;23:60-66. doi: 10.1016/j.reth.2023.04.001. eCollection 2023 Jun.

ABSTRACT

INTRODUCTION: Over the past few years, stem cells have represented a promising treatment in neurological disorders due to the well-defined characteristics of their capability to proliferate and differentiate into any cell type, both in vitro and in vivo. Additionally, previous studies have shown that calcium signaling modulates the proliferation and differentiation of neural progenitor cells. The present study investigated the effect of carbachol (CCh), a cholinergic agonist activating acetylcholine receptors, with and without calcium, on the neural differentiation of human adipose tissue-derived mesenchymal stem cells (hADSCs) in neural media, including forskolin and 3-isobutyl-1-methyl-xanthine and retinoic acid.

METHODS: For this purpose, first, the MTT assay and acridine orange staining were studied to obtain the optimal concentration of CCh. Next, the differentiation tests, such as cellular calcium assay as well as evaluation of qualitative and quantitative expression of neuronal index markers through immunofluorescence staining and gene expression analysis, respectively, were performed on days 7 and 14 of the differentiation period.

RESULTS: According to the results, CCh at 1 μM concentration had no cytotoxicity on hADSCs and also induced cell proliferation. Furthermore, CCh with and without calcium increased the expression of neural-specific genes (NSE, MAP2, β-III-tubulin, and MAPK3) and proteins (γ-enolase, MAP2, and β-III-tubulin) as well as the amount of calcium in differentiated hADSCs at 7 and 14 days after induction.

CONCLUSIONS: In conclusion, the findings suggest that CCh acts as an influential therapeutic factor in the field of neural regenerative medicine and research.

PMID:37122359 | PMC:PMC10130343 | DOI:10.1016/j.reth.2023.04.001

Categories: Literature Watch

Whole genome resequencing and phenotyping of MAGIC population for high resolution mapping of drought tolerance in chickpea

Mon, 2023-05-01 06:00

Plant Genome. 2023 Apr 30:e20333. doi: 10.1002/tpg2.20333. Online ahead of print.

ABSTRACT

Terminal drought is one of the major constraints to crop production in chickpea (Cicer arietinum L.). In order to map drought tolerance related traits at high resolution, we sequenced multi-parent advanced generation intercross (MAGIC) population using whole genome resequencing approach and phenotyped it under drought stress environments for two consecutive years (2013-14 and 2014-15). A total of 52.02 billion clean reads containing 4.67 TB clean data were generated on the 1136 MAGIC lines and eight parental lines. Alignment of clean data on to the reference genome enabled identification of a total, 932,172 of SNPs, 35,973 insertions, and 35,726 deletions among the parental lines. A high-density genetic map was constructed using 57,180 SNPs spanning a map distance of 1606.69 cM. Using compressed mixed linear model, genome-wide association study (GWAS) enabled us to identify 737 markers significantly associated with days to 50% flowering, days to maturity, plant height, 100 seed weight, biomass, and harvest index. In addition to the GWAS approach, an identity-by-descent (IBD)-based mixed model approach was used to map quantitative trait loci (QTLs). The IBD-based mixed model approach detected major QTLs that were comparable to those from the GWAS analysis as well as some exclusive QTLs with smaller effects. The candidate genes like FRIGIDA and CaTIFY4b can be used for enhancing drought tolerance in chickpea. The genomic resources, genetic map, marker-trait associations, and QTLs identified in the study are valuable resources for the chickpea community for developing climate resilient chickpeas.

PMID:37122200 | DOI:10.1002/tpg2.20333

Categories: Literature Watch

Worldwide emergence of fluconazole-resistant Candida parapsilosis: current framework and future research roadmap

Sun, 2023-04-30 06:00

Lancet Microbe. 2023 Apr 27:S2666-5247(23)00067-8. doi: 10.1016/S2666-5247(23)00067-8. Online ahead of print.

ABSTRACT

Candida parapsilosis is one of the most commen causes of life-threatening candidaemia, particularly in premature neonates, individuals with cancer of the haematopoietic system, and recipients of organ transplants. Historically, drug-susceptible strains have been linked to clonal outbreaks. However, worldwide studies started since 2018 have reported severe outbreaks among adults caused by fluconazole-resistant strains. Outbreaks caused by fluconazole-resistant strains are associated with high mortality rates and can persist despite strict infection control strategies. The emergence of resistance threatens the efficacy of azoles, which is the most widely used class of antifungals and the only available oral treatment option for candidaemia. The fact that most patients infected with fluconazole-resistant strains are azole-naive underscores the high potential adaptability of fluconazole-resistant strains to diverse hosts, environmental niches, and reservoirs. Another concern is the multidrug-resistant and echinocandin-tolerant C parapsilosis isolates, which emerged in 2020. Raising awareness, establishing effective clinical interventions, and understanding the biology and pathogenesis of fluconazole-resistant C parapsilosis are urgently needed to improve treatment strategies and outcomes.

PMID:37121240 | DOI:10.1016/S2666-5247(23)00067-8

Categories: Literature Watch

Matching single cells across modalities with contrastive learning and optimal transport

Sun, 2023-04-30 06:00

Brief Bioinform. 2023 Apr 29:bbad130. doi: 10.1093/bib/bbad130. Online ahead of print.

ABSTRACT

Understanding the interactions between the biomolecules that govern cellular behaviors remains an emergent question in biology. Recent advances in single-cell technologies have enabled the simultaneous quantification of multiple biomolecules in the same cell, opening new avenues for understanding cellular complexity and heterogeneity. Still, the resulting multimodal single-cell datasets present unique challenges arising from the high dimensionality and multiple sources of acquisition noise. Computational methods able to match cells across different modalities offer an appealing alternative towards this goal. In this work, we propose MatchCLOT, a novel method for modality matching inspired by recent promising developments in contrastive learning and optimal transport. MatchCLOT uses contrastive learning to learn a common representation between two modalities and applies entropic optimal transport as an approximate maximum weight bipartite matching algorithm. Our model obtains state-of-the-art performance on two curated benchmarking datasets and an independent test dataset, improving the top scoring method by 26.1% while preserving the underlying biological structure of the multimodal data. Importantly, MatchCLOT offers high gains in computational time and memory that, in contrast to existing methods, allows it to scale well with the number of cells. As single-cell datasets become increasingly large, MatchCLOT offers an accurate and efficient solution to the problem of modality matching.

PMID:37122067 | DOI:10.1093/bib/bbad130

Categories: Literature Watch

Inversion polymorphism in a complete human genome assembly

Sun, 2023-04-30 06:00

Genome Biol. 2023 Apr 30;24(1):100. doi: 10.1186/s13059-023-02919-8.

ABSTRACT

The telomere-to-telomere (T2T) complete human reference has significantly improved our ability to characterize genome structural variation. To understand its impact on inversion polymorphisms, we remapped data from 41 genomes against the T2T reference genome and compared it to the GRCh38 reference. We find a ~ 21% increase in sensitivity improving mapping of 63 inversions on the T2T reference. We identify 26 misorientations within GRCh38 and show that the T2T reference is three times more likely to represent the correct orientation of the major human allele. Analysis of 10 additional samples reveals novel rare inversions at chromosomes 15q25.2, 16p11.2, 16q22.1-23.1, and 22q11.21.

PMID:37122002 | DOI:10.1186/s13059-023-02919-8

Categories: Literature Watch

The role of long noncoding RNAs in malaria parasites

Sun, 2023-04-30 06:00

Trends Parasitol. 2023 Apr 29:S1471-4922(23)00077-6. doi: 10.1016/j.pt.2023.03.016. Online ahead of print.

ABSTRACT

The human malaria parasites, including Plasmodium falciparum, persist as a major cause of global morbidity and mortality. The recent stalling of progress toward malaria elimination substantiates a need for novel interventions. Controlled gene expression is central to the parasite's numerous life cycle transformations and adaptation. With few specific transcription factors (TFs) identified, crucial roles for chromatin states and epigenetics in parasite transcription have become evident. Although many chromatin-modifying enzymes are known, less is known about which factors mediate their impacts on transcriptional variation. Like those of higher eukaryotes, long noncoding RNAs (lncRNAs) have recently been shown to have integral roles in parasite gene regulation. This review aims to summarize recent developments and key findings on the role of lncRNAs in P. falciparum.

PMID:37121862 | DOI:10.1016/j.pt.2023.03.016

Categories: Literature Watch

Generation of Human Embryonic Stem Cell-Derived Lung Organoids for Modeling Infection and Replication Differences between Human Adenovirus Types 3 and 55 and Evaluating Potential Antiviral Drugs

Sun, 2023-04-30 06:00

J Virol. 2023 May 1:e0020923. doi: 10.1128/jvi.00209-23. Online ahead of print.

ABSTRACT

Human adenoviruses type 3 (HAdV-3) and type 55 (HAdV-55) are frequently encountered, highly contagious respiratory pathogens with high morbidity rate. In contrast to HAdV-3, one of the most predominant types in children, HAdV-55 is a reemergent pathogen associated with more severe community-acquired pneumonia (CAP) in adults, especially in military camps. However, the infectivity and pathogenicity differences between these viruses remain unknown as in vivo models are not available. Here, we report a novel system utilizing human embryonic stem cells-derived 3-dimensional airway organoids (hAWOs) and alveolar organoids (hALOs) to investigate these two viruses. Firstly, HAdV-55 replicated more robustly than HAdV-3. Secondly, cell tropism analysis in hAWOs and hALOs by immunofluorescence staining revealed that HAdV-55 infected more airway and alveolar stem cells (basal and AT2 cells) than HAdV-3, which may lead to impairment of self-renewal functions post-injury and the loss of cell differentiation in lungs. Additionally, the viral life cycles of HAdV-3 and -55 in organoids were also observed using Transmission Electron Microscopy. This study presents a useful pair of lung organoids for modeling infection and replication differences between respiratory pathogens, illustrating that HAdV-55 has relatively higher replication efficiency and more specific cell tropism in human lung organoids than HAdV-3, which may result in relatively higher pathogenicity and virulence of HAdV-55 in human lungs. The model system is also suitable for evaluating potential antiviral drugs, as demonstrated with cidofovir. IMPORTANCE Human adenovirus (HAdV) infections are a major threat worldwide. HAdV-3 is one of the most predominant respiratory pathogen types found in children. Many clinical studies have reported that HAdV-3 causes less severe disease. In contrast, HAdV-55, a reemergent acute respiratory disease pathogen, is associated with severe community-acquired pneumonia in adults. Currently, no ideal in vivo models are available for studying HAdVs. Therefore, the mechanism of infectivity and pathogenicity differences between human adenoviruses remain unknown. In this study, a useful pair of 3-dimensional (3D) airway organoids (hAWOs) and alveolar organoids (hALOs) were developed to serve as a model. The life cycles of HAdV-3 and HAdV-55 in these human lung organoids were documented for the first time. These 3D organoids harbor different cell types, which are similar to the ones found in humans. This allows for the study of the natural target cells for infection. The finding of differences in replication efficiency and cell tropism between HAdV-55 and -3 may provide insights into the mechanism of clinical pathogenicity differences between these two important HAdV types. Additionally, this study provides a viable and effective in vitro tool for evaluating potential anti-adenoviral treatments.

PMID:37120831 | DOI:10.1128/jvi.00209-23

Categories: Literature Watch

Examining asymmetric pairwise pre-reaction and transition states in enzymatic catalysis by molecular dynamics simulation and quantum mechanics/molecular mechanics calculation

Sun, 2023-04-30 06:00

STAR Protoc. 2023 Apr 28;4(2):102263. doi: 10.1016/j.xpro.2023.102263. Online ahead of print.

ABSTRACT

Here, we present a protocol to examine asymmetric pairwise pre-reaction and transition states in enzymatic catalysis. We describe steps to set up the calculated systems, run umbrella sampling molecular dynamics simulation, and conduct quantum mechanics/molecular mechanics calculations. We also provide analytical scripts to yield potential of mean force of pre-reaction states and reaction barriers. This protocol can generate quantum-mechanistic data for constructing pre-reaction state/transition state machine learning models. For complete details on the use and execution of this protocol, please refer to Luo et al. (2022).1.

PMID:37120814 | DOI:10.1016/j.xpro.2023.102263

Categories: Literature Watch

Phylogenetic analysis based on the ITS, matK and rbcL DNA barcodes and comparison of chemical contents of twelve Paeonia taxa in Türkiye

Sun, 2023-04-30 06:00

Mol Biol Rep. 2023 Apr 30. doi: 10.1007/s11033-023-08435-z. Online ahead of print.

ABSTRACT

BACKGROUD: Twelve taxa of herbaceous Paeonia species were recorded in Türkiye. All definitions were performed morphologically and/or anatomically and there is no study based on DNA barcode sequences. Three barcode regions were sequenced to determine the phylogenetic relationships of Turkish Paeonia taxa. The chemical comparison of roots was also investigated.

METHODS AND RESULTS: The taxons were collected between May and June 2021 from nine cities. Leaf materials were used for DNA isolation and ITS, matK and rbcL regions were amplified and sequenced. There was no difference among taxa in terms of rbcL sequences. But the ITS and matK regions distinguished 12 taxa and structured them in two groups. ITS region distinguished P. peregrina, P. arietina, and P. tenuifolia from other taxa, while matK region distinguished P. arietina and P. witmanniana from other taxa. Both barcode sequences actually showed that the registration of P. mascula subsp. arasicola was actually 100% similar to P. arietina. ITS was the most polymorphic region (n = 54) followed by matK (n = 9). These sequences could successfully discriminate Paoenia species from each other and diploid P. tenuifolia. The methanolic root (100 gr) extracts were examined for total phenolic and flavonoid content, and antioxidant activities. Significant variation was found for polyphenolic content, and antioxidant properties (TPC from 204.23 to 2343.89 mg, TFC from 7.73 to 66.16 mg, and FRAP from 523.81 to 4338.62 mg). SC50 values of ABTS and DPPH were ranged from 115.08 to 1115.52 μg/ml and 73.83 to 963.59 μg/ml, respectively.

CONCLUSION: It was concluded that 11 of 12 taxa had differences in terms of ITS and matK sequences and these region must be used for the correct identification of Turkish Paeonia.

PMID:37120793 | DOI:10.1007/s11033-023-08435-z

Categories: Literature Watch

Oligomeric states of ASC specks regulate inflammatory responses by inflammasome in the extracellular space

Sat, 2023-04-29 06:00

Cell Death Discov. 2023 Apr 29;9(1):142. doi: 10.1038/s41420-023-01438-6.

ABSTRACT

Inflammasomes are multi-protein complexes and play a crucial role in host defense against pathogens. Downstream inflammatory responses through inflammasomes are known to be related to the oligomerization degree of ASC specks, but the detailed mechanism still remains unexplored. Here, we demonstrate that oligomerization degrees of ASC specks regulate the caspase-1 activation in the extracellular space. A protein binder specific for a pyrin domain (PYD) of ASC (ASCPYD) was developed, and structural analysis revealed that the protein binder effectively inhibits the interaction between PYDs, disassembling ASC specks into low oligomeric states. ASC specks with a low oligomerization degree were shown to enhance the activation of caspase-1 by recruiting and processing more premature caspase-1 through interactions between CARD of caspase-1 (caspase-1CARD) and CARD of ASC (ASCCARD). These findings can provide insight into controlling the inflammasome-mediated inflammatory process as well as the development of inflammasome-targeting drugs.

PMID:37120628 | DOI:10.1038/s41420-023-01438-6

Categories: Literature Watch

mTORC2 interactome and localization determine aggressiveness of high-grade glioma cells through association with gelsolin

Sat, 2023-04-29 06:00

Sci Rep. 2023 Apr 29;13(1):7037. doi: 10.1038/s41598-023-33872-y.

ABSTRACT

mTOR complex 2 (mTORC2) has been implicated as a key regulator of glioblastoma cell migration. However, the roles of mTORC2 in the migrational control process have not been entirely elucidated. Here, we elaborate that active mTORC2 is crucial for GBM cell motility. Inhibition of mTORC2 impaired cell movement and negatively affected microfilament and microtubule functions. We also aimed to characterize important players involved in the regulation of cell migration and other mTORC2-mediated cellular processes in GBM cells. Therefore, we quantitatively characterized the alteration of the mTORC2 interactome under selective conditions using affinity purification-mass spectrometry in glioblastoma. We demonstrated that changes in cell migration ability specifically altered mTORC2-associated proteins. GSN was identified as one of the most dynamic proteins. The mTORC2-GSN linkage was mostly highlighted in high-grade glioma cells, connecting functional mTORC2 to multiple proteins responsible for directional cell movement in GBM. Loss of GSN disconnected mTORC2 from numerous cytoskeletal proteins and affected the membrane localization of mTORC2. In addition, we reported 86 stable mTORC2-interacting proteins involved in diverse molecular functions, predominantly cytoskeletal remodeling, in GBM. Our findings might help expand future opportunities for predicting the highly migratory phenotype of brain cancers in clinical investigations.

PMID:37120454 | DOI:10.1038/s41598-023-33872-y

Categories: Literature Watch

Positive feedback induces switch between distributive and processive phosphorylation of Hog1

Sat, 2023-04-29 06:00

Nat Commun. 2023 Apr 29;14(1):2477. doi: 10.1038/s41467-023-37430-y.

ABSTRACT

Cellular decision making often builds on ultrasensitive MAPK pathways. The phosphorylation mechanism of MAP kinase has so far been described as either distributive or processive, with distributive mechanisms generating ultrasensitivity in theoretical analyses. However, the in vivo mechanism of MAP kinase phosphorylation and its activation dynamics remain unclear. Here, we characterize the regulation of the MAP kinase Hog1 in Saccharomyces cerevisiae via topologically different ODE models, parameterized on multimodal activation data. Interestingly, our best fitting model switches between distributive and processive phosphorylation behavior regulated via a positive feedback loop composed of an affinity and a catalytic component targeting the MAP kinase-kinase Pbs2. Indeed, we show that Hog1 directly phosphorylates Pbs2 on serine 248 (S248), that cells expressing a non-phosphorylatable (S248A) or phosphomimetic (S248E) mutant show behavior that is consistent with simulations of disrupted or constitutively active affinity feedback and that Pbs2-S248E shows significantly increased affinity to Hog1 in vitro. Simulations further suggest that this mixed Hog1 activation mechanism is required for full sensitivity to stimuli and to ensure robustness to different perturbations.

PMID:37120434 | DOI:10.1038/s41467-023-37430-y

Categories: Literature Watch

A systematic review of computational approaches to understand cancer biology for informed drug repurposing

Sat, 2023-04-29 06:00

J Biomed Inform. 2023 Apr 27:104373. doi: 10.1016/j.jbi.2023.104373. Online ahead of print.

ABSTRACT

Cancer is the second leading cause of death globally, trailing only heart disease. In the United States alone, 1.9 million new cancer cases and 609,360 deaths were recorded for 2022. Unfortunately, the success rate for new cancer drug development remains less than 10%, making the disease particularly challenging. This low success rate is largely attributed to the complex and poorly understood nature of cancer etiology. Therefore, it is critical to find alternative approaches to understanding cancer biology and developing effective treatments. One such approach is drug repurposing, which offers a shorter drug development timeline and lower costs while increasing the likelihood of success. In this review, we provide a comprehensive analysis of computational approaches for understanding cancer biology, including systems biology, multi-omics, and pathway analysis. Additionally, we examine the use of these methods for drug repurposing in cancer, including the databases and tools that are used for cancer research. Finally, we present case studies of drug repurposing, discussing their limitations and offering recommendations for future research in this area.

PMID:37120047 | DOI:10.1016/j.jbi.2023.104373

Categories: Literature Watch

Transcription factor induction of vascular blood stem cell niches in vivo

Sat, 2023-04-29 06:00

Dev Cell. 2023 Apr 25:S1534-5807(23)00160-0. doi: 10.1016/j.devcel.2023.04.007. Online ahead of print.

ABSTRACT

The hematopoietic niche is a supportive microenvironment composed of distinct cell types, including specialized vascular endothelial cells that directly interact with hematopoietic stem and progenitor cells (HSPCs). The molecular factors that specify niche endothelial cells and orchestrate HSPC homeostasis remain largely unknown. Using multi-dimensional gene expression and chromatin accessibility analyses in zebrafish, we define a conserved gene expression signature and cis-regulatory landscape that are unique to sinusoidal endothelial cells in the HSPC niche. Using enhancer mutagenesis and transcription factor overexpression, we elucidate a transcriptional code that involves members of the Ets, Sox, and nuclear hormone receptor families and is sufficient to induce ectopic niche endothelial cells that associate with mesenchymal stromal cells and support the recruitment, maintenance, and division of HSPCs in vivo. These studies set forth an approach for generating synthetic HSPC niches, in vitro or in vivo, and for effective therapies to modulate the endogenous niche.

PMID:37119815 | DOI:10.1016/j.devcel.2023.04.007

Categories: Literature Watch

A Transcriptional Cofactor Regulatory Network for the C. elegans Intestine

Sat, 2023-04-29 06:00

G3 (Bethesda). 2023 Apr 29:jkad096. doi: 10.1093/g3journal/jkad096. Online ahead of print.

ABSTRACT

Chromatin modifiers and transcriptional cofactors (collectively referred to as CFs) work with DNA-binding transcription factors (TFs) to regulate gene expression. In multicellular eukaryotes, distinct tissues each execute their own gene expression program for accurate differentiation and subsequent functionality. While the function of TFs in differential gene expression has been studied in detail in many systems, the contribution of CFs has remained less explored. Here we uncovered the contributions of CFs to gene regulation in the Caenorhabditis elegans intestine. We first annotated 366 CFs encoded by the C. elegans genome and assembled a library of 335 RNAi clones. Using this library, we analyzed the effects of individually depleting these CFs on the expression of 19 fluorescent transcriptional reporters in the intestine and identified 216 regulatory interactions. We found that different CFs regulate different promoters, and that both essential and intestinally expressed CFs have the greatest effects on promoter activity. We did not find all members of CF complexes acting on the same set of reporters but instead found diversity in the promoter targets of each complex component. Finally, we found that previously identified activation mechanisms for the acdh-1 promoter use different CFs and TFs. Overall, we demonstrate that CFs function specifically rather than ubiquitously at intestinal promoters and provide an RNAi resource for reverse genetic screens.

PMID:37119809 | DOI:10.1093/g3journal/jkad096

Categories: Literature Watch

Evaluating the seroprevalence of SARS-CoV-2 IgG in five different districts of Bangladesh. A seroepidemiological study

Sat, 2023-04-29 06:00

J Infect Public Health. 2023 Apr 17;16(6):964-973. doi: 10.1016/j.jiph.2023.04.013. Online ahead of print.

ABSTRACT

BACKGROUND: We aimed to measure the seroprevalences and levels of anti-SARS-CoV-2 IgG in children, unvaccinated and vaccinated adults in five districts of Bangladesh and thus, investigate the association of seroprevalence and anti-SARS-CoV-2 IgG level with respect to different attributes of study participants.

METHODS: In the present study, the seroprevalences and levels of plasma anti-SARS-CoV-2 IgG were measured in children (n = 202), unvaccinated adults (n = 112), and vaccinated adults (n = 439) using quantitative ELISA.

RESULTS: The overall seroprevalence in the three groups of the study participants were 58.3% (90%CrI: 52.3-64.2%), 62.2% (90%CrI: 54.4-70.0%) and 90.7% (90%CrI: 88.3-92.9%), respectively. Multivariate logistic and linear regression revealed no significant association of seropositivity and levels of anti-SARS-CoV-2 IgG with the baseline characteristics of the children. AB blood group (vs A; aOR=0.21, 95% CI: 0.04-0.92, p = 0.04), O blood group (vs A; aOR=0.09, 95% CI: 0.02-0.32, p = 0.0004), BMI (aOR=1.61, 95% CI: 1.14-2.37, p = 0.01) and overweight obesity status (vs normal, aOR=0.12, 95% CI: 0.02-0.76, p = 0.03) were significantly associated with seropositivity in unvaccinated adults after adjusting for confounders. Age (p = 0.002) was significantly associated with anti-SARS-CoV-2 level in vaccinated adults after adjusting for confounders. Most of the children and unvaccinated adults belonged to the lower antibody response class which implicates the necessity of vaccination.

CONCLUSION: This study portrays a better way of evaluating transmission of virus and gain a better understanding of the true extent of infection as illustrated by the high rates of seroprevalences in children and unvaccinated adults. The findings of this study depicted from the antibody response also suggest the importance of vaccination.

PMID:37119719 | DOI:10.1016/j.jiph.2023.04.013

Categories: Literature Watch

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