DNA-binding Transcription Factors Research Articles

Quantitative imaging reveals the role of MpARF proteasomal degradation during gemma germination

The auxin signaling molecule controls a variety of growth and developmental processes in land plants. Auxin regulates gene expression through a nuclear auxin signaling pathway (NAP) consisting of a ubiquitin ligase auxin receptor TIR1/AFB, its Aux/IAA degradation substrate, and DNA-binding ARF transcription factors. While extensive qualitative understanding of the pathway and its interactions has been obtained, mostly by studying the flowering plant Arabidopsis thaliana, it is so far unknown how these translate to quantitative system behaviour in vivo, a problem that is confounded by large NAP gene families in most species. Here we used the minimal NAP of the liverwort Marchantia polymorpha to quantitatively map NAP protein accumulation and dynamics in vivo through the use of knock-in fluorescent fusion proteins. Beyond revealing the dynamic native accumulation profile of the entire NAP protein network, we discovered that the two central ARFs, MpARF1 and MpARF2, are proteasomally degraded. This auxin-independent degradation tunes ARF protein stoichiometry to favor gene activation, thereby reprogramming auxin response during developmental progression. Thus, quantitative analysis of the entire NAP allowed us to identify ARF degradation and stoichiometries of activator and repressor ARFs as a potential mechanism for controlling gemma germination.

Predicting regulatory mutations and their target genes by new computational integrative analysis: A study of follicular lymphoma

Mutations in DNA regulatory regions are increasingly being recognized as important drivers of cancer and other complex diseases. These mutations can regulate gene expression by affecting DNA-protein binding and epigenetic profiles, such as DNA methylation in genome regulatory elements. However, identifying mutation hotspots associated with expression regulation and disease progression in non-coding DNA remains a challenge. Unlike most existing approaches that assign a mutation score to individual single nucleotide polymorphisms (SNP), a mutation block (MB)-based approach was introduced in this study to assess the collective impact of a cluster of SNPs on transcription factor-DNA binding affinity, differential gene expression (DEG), and nearby DNA methylation. Moreover, the long-distance target genes of functional MBs were identified using a new permutation-based algorithm that assessed the significance of correlations between DNA methylation at regulatory regions and target gene expression. Two new Python packages were developed. The Differential Methylation Region (DMR-analysis) analysis tool was used to detect DMR and map them to regulatory elements. The second tool, an integrated DMR, DEG, and SNP analysis tool (DDS-analysis), was used to combine the omics data to identify functional MBs and long-distance target genes. Both tools were validated in follicular lymphoma (FL) cohorts, where not only known functional MBs and their target genes (BCL2 and BCL6) were recovered, but also novel genes were found, including CDCA4 and JAG2, which may be associated with FL development. These genes are linked to target gene expression and are significantly correlated with the methylation of nearby DNA sequences in FL. The proposed computational integrative analysis of multiomics data holds promise for identifying regulatory mutations in cancer and other complex diseases.

Systematic assessment of ISWI subunits shows that NURF creates local accessibility for CTCF

Catalytic activity of the imitation switch (ISWI) family of remodelers is critical for nucleosomal organization and DNA binding of certain transcription factors, including the insulator protein CTCF. Here we define the contribution of individual subcomplexes by deriving a panel of isogenic mouse stem cell lines, each lacking one of six ISWI accessory subunits. Individual deletions of subunits of either CERF, RSF, ACF, WICH or NoRC subcomplexes only moderately affect the chromatin landscape, while removal of the NURF-specific subunit BPTF leads to a strong reduction in chromatin accessibility and SNF2H ATPase localization around CTCF sites. This affects adjacent nucleosome occupancy and CTCF binding. At a group of sites with reduced chromatin accessibility, CTCF binding persists but cohesin occupancy is reduced, resulting in decreased insulation. These results suggest that CTCF binding can be separated from its function as an insulator in nuclear organization and identify a specific role for NURF in mediating SNF2H localization and chromatin opening at bound CTCF sites.

Deep DNAshape webserver: prediction and real-time visualization of DNA shape considering extended k-mers.

Sequence-dependent DNA shape plays an important role in understanding protein-DNA binding mechanisms. High-throughput prediction of DNA shape features has become a valuable tool in the field of protein-DNA recognition, transcription factor-DNA binding specificity, and gene regulation. However, our widely used webserver, DNAshape, relies on statistically summarized pentamer query tables to query DNA shape features. These query tables do not consider flanking regions longer than two base pairs, and acquiring a query table for hexamers or higher-order k-mers is currently still unrealistic due to limitations in achieving sufficient statistical coverage in molecular simulations or structural biology experiments. A recent deep-learning method, Deep DNAshape, can predict DNA shape features at the core of a DNA fragment considering flanking regions of up to seven base pairs, trained on limited simulation data. However, Deep DNAshape is rather complicated to install, and it must run locally compared to the pentamer-based DNAshape webserver, creating a barrier for users. Here, we present the Deep DNAshape webserver, which has the benefits of both methods while being accurate, fast, and accessible to all users. Additional improvements of the webserver include the detection of user input in real time, the ability of interactive visualization tools and different modes of analyses. URL: https://deepdnashape.usc.edu.

The Mechanism of "Treating Different Diseases with the Same Treatment" by Qiangji Jianpi Decoction in Ankylosing Spondylitis Combined with Inflammatory Bowel Disease: A Comprehensive Analysis of Multiple Methods.

Ankylosing spondylitis (AS) and inflammatory bowel disease (IBD) are prevalent autoimmune disorders that often co-occur, posing significant treatment challenges. This investigation adopts a multidisciplinary strategy, integrating bioinformatics, network pharmacology, molecular docking, and Mendelian randomization, to elucidate the relationship between AS and IBD and to investigate the potential mechanisms of traditional Chinese medicine formulations, represented by Qiangji Jianpi (QJJP) decoction, in treating these comorbid conditions. We utilized databases to pinpoint common targets among AS, IBD, and QJJP decoction's active compounds through intersection analysis. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, we mapped a network in Cytoscape, isolating critical targets. Molecular docking with AutoDock validated the affinity between targets and compounds. ROC analysis and dataset validation assessed diagnostic performance, while Gene Set Enrichment Analysis (GSEA) offered pathway insights. Mendelian randomization explored the AS-IBD causal relationship. Screening identified 105 targets for QJJP decoction, 414 for AS, and 2420 for IBD, with 85 overlapping. These targets predominantly participate in organismal responses and DNA transcription factor binding, with a significant cellular presence in the endoplasmic reticulum and vesicle lumen. Molecular docking, facilitated by Cytoscape, confirmed IL1A, IFNG, TGFB1, and EDN1 as critical targets, with IFNG demonstrating diagnostic potential through GEO dataset validation. The integration of GSEA with network pharmacology highlighted the therapeutic significance of the relaxin, osteoclast differentiation, HIF-1, and AGE-RAGE signaling pathways in QJJP decoction's action. Mendelian randomization analysis indicated a positive causal relationship between IBD and AS, pinpointing rs2193041 as a key SNP influencing IFNG. Based on the principle of "treating different diseases with the same method" in traditional Chinese medicine theory, we explored the intricate mechanisms through which QJJP decoction addresses AS and IBD comorbidity. Our research spotlighted the pivotal role of the IFNG gene. IFNG emerges not only as a key therapeutic target but also assumes significance as a potential diagnostic biomarker through its genetic underpinnings. This investigation establishes a solid base for subsequent experimental inquiries. Our findings introduce novel approaches for incorporating traditional Chinese medicine into the treatment of AS-IBD comorbidity, setting the stage for groundbreaking research directions.

CBFA2T3 Is PPARA Sensitive and Attenuates Fasting-Induced Lipid Accumulation in Mouse Liver.

Peroxisome proliferator-activated receptor alpha (PPARA) is a ligand-activated transcription factor that is a key mediator of lipid metabolism and metabolic stress in the liver. Accumulating evidence shows that PPARA regulates the expression of various protein coding and non-coding genes that modulate metabolic stress in the liver. CBFA2/RUNX1 partner transcriptional co-repressor 3 (CBFA2T3) is a DNA-binding transcription factor that belongs to the myeloid translocation gene family. Many studies have shown that CBFA2T3 is associated with acute myeloid leukemia. Especially, CBFA2T3-GLIS2 fusion is a chimeric oncogene associated with a poor survival rate in pediatric acute megakaryocytic leukemia. A previous study identified that PPARA activation promoted Cbfa2t3 induction in liver and that Cbfa2t3 may have a modulatory role in metabolic stress. However, the effect of CBFA2T3 gene expression on metabolic stress is not understood. In this study, the PPARA ligand WY14643 activated Cbfa2t3 expression in mouse liver. Glucose tolerance test and insulin tolerance test data showed that insulin resistance is increased in Cbfa2t3-/- mice compared to Cbfa2t3+/+ mice. Hepatic CBFA2T3 modulates heat shock protein family A member 1b and carbonic anhydrase 5a expression. Histology analysis revealed lipid droplet and lipid accumulation in the liver of fasting Cbfa2t3-/- mice but not Cbfa2t3+/+ mice. The expression of lipid accumulation-related genes, such as Cd36, Cidea, and Fabp1, was increased in the liver of fasting Cbfa2t3-/- mice. Especially, basal expression levels of Cidea mRNA were elevated in the liver of Cbfa2t3-/- mice compared to Cbfa2t3+/+ mice. Much higher induction of Cidea mRNA was seen in the liver of Cbfa2t3-/- mice after WY14643 administration. These results indicate that hepatic CBFA2T3 is a PPARA-sensitive gene that may modulate metabolic stress in mouse liver.

GhiPLATZ17 and GhiPLATZ22, zinc-dependent DNA-binding transcription factors, promote salt tolerance in upland cotton.

The utilization of transcriptome analysis, functional validation, VIGS, and DAB techniques have provided evidence that GhiPLATZ17 and GhiPLATZ22 play a pivotal role in improving the salt tolerance of upland cotton. PLATZ (Plant AT-rich sequences and zinc-binding proteins) are known to be key regulators in plant growth, development, and response to salt stress. In this study, we comprehensively analyzed the PLATZ family in ten cotton species in response to salinity stress. Gossypium herbaceum boasts 25 distinct PLATZ genes, paralleled by 24 in G. raimondii, 25 in G. arboreum, 46 in G. hirsutum, 48 in G. barbadense, 43 in G. tomentosum, 67 in G. mustelinum, 60 in G. darwinii, 46 in G. ekmanianum, and a total of 53 PLATZ genes attributed to G. stephensii. The PLATZ gene family shed light on the hybridization and allopolyploidy events that occurred during the evolutionary history of allotetraploid cotton. Ka/Ks analysis suggested that the PLATZ gene family underwent intense purifying selection during cotton evolution. Analysis of synteny and gene collinearity revealed a complex pattern of segmental and dispersed duplication events to expand PLATZ genes in cotton. Cis-acting elements and gene expressions revealed that GhiPLATZ exhibited salt stress resistance. Transcriptome analysis, functional validation, virus-induced gene silencing (VIGS), and diaminobenzidine staining (DAB) demonstrated that GhiPLATZ17 and GhiPLATZ22 enhance salt tolerance in upland cotton. The study can potentially advance our understanding of identifying salt-resistant genes in cotton.

Establishing cell suitability for high-level production of licorice triterpenoids in yeast

Yeast has been an indispensable host for synthesizing complex plant-derived natural compounds, yet the yields remained largely constrained. This limitation mainly arises from overlooking the importance of cell and pathway suitability during the optimization of enzymes and pathways. Herein, beyond conventional enzyme engineering, we dissected metabolic suitability with a framework for simultaneously augmenting cofactors and carbon flux to enhance the biosynthesis of heterogenous triterpenoids. We further developed phospholipid microenvironment engineering strategies, dramatically improving yeast's suitability for the high performance of endoplasmic reticulum (ER)-localized, rate-limiting plant P450s. Combining metabolic and microenvironment suitability by manipulating only three genes, NHMGR (NADH-dependent HMG-CoA reductase), SIP4 (a DNA-binding transcription factor)and GPP1 (Glycerol-1-phosphate phosphohydrolase 1), we enabled the high-level production of 4.92 g/L rare licorice triterpenoids derived from consecutive oxidation of β-amyrin by two P450 enzymes after fermentation optimization. This production holds substantial commercial value, highlighting the critical role of establishing cell suitability in enhancing triterpenoid biosynthesis and offering a versatile framework applicable to various plant natural product biosynthetic pathways.

Transcriptome differential expression analysis of defoliation of two different lemon varieties.

'Allen Eureka' is a bud variety of Eureka lemon with excellent fruiting traits. However, it suffers from severe winter defoliation that leads to a large loss of organic nutrients and seriously affects the tree's growth and development as well as the yield of the following year, and the mechanism of its response to defoliation is still unclear. In order to investigate the molecular regulatory mechanisms of different leaf abscission periods in lemon, two lemon cultivars ('Allen Eureka' and 'Yunning No. 1') with different defoliation traits were used as materials. The petiole abscission zone (AZ) was collected at three different defoliation stages, namely, the pre-defoliation stage (CQ), the mid-defoliation stage (CZ), and the post-defoliation stage (CH). Transcriptome sequencing was performed to analyze the gene expression differences between these two cultivars. A total of 898, 4,856, and 3,126 differentially expressed genes (DEGs) were obtained in CQ, CZ, and CH, respectively, and the number of DEGs in CZ was the largest. GO analysis revealed that the DEGs between the two cultivars were mainly enriched in processes related to oxidoreductase, hydrolase, DNA binding transcription factor, and transcription regulator activity in the defoliation stages. KEGG analysis showed that the DEGs were concentrated in CZ and involved plant hormone signal transduction, phenylpropanoid biosynthesis, glutathione metabolism, and alpha-linolenic acid metabolism. The expression trends of some DEGs suggested their roles in regulating defoliation in lemon. Eight gene families were obtained by combining DEG clustering analysis and weighted gene co-expression network analysis (WGCNA), including β-glucosidase, AUX/IAA, SAUR, GH3, POD, and WRKY, suggesting that these genes may be involved in the regulation of lemon leaf abscission. The above conclusions enrich the research related to lemon leaf abscission and provide reliable data for the screening of lemon defoliation candidate genes and analysis of defoliation pathways.

Inhibitory potential of Syzygium aromaticum against Fusarium oxysporum f. sp. lycopersici: In-vitro analysis and molecular docking studies

The antifungal potential of the extract of cloves (Syzygium aromaticum) was investigated in this study. The crude extracts of cloves and n-hexane, chloroform and n-butanol fractions were prepared. The antifungal activity of obtained fractions was studied at various concentrations ranging from 1.5 to 200.00 µg/mL. Thiophanate methyl (TM) was used as +ve control in this study. The fractions including methanolic, n-hexane, n-butanol, and chloroform significantly inhibited the growth of Fusarium oxysporum f.sp. lycopersici (FOL) ranging from 93.8 to 100 % when used at 200 µg/mL. The chloroform fraction showed 6.25 µg/mL MIC as compared to TM with 64 µg/mL MIC. GC/MS analysis showed that the chloroform fraction contained Eugenol, Phenol, 2,2′-methylenebis[6-(1,1-dimethylethyl)-4-methyl, 2,4-Di‑tert-butylphenol, n-Hexadecanoic acid, Phenol, and 2‑methoxy-4-(2-propenyl)- acetate. The findings of in-vitro antifungal analysis were further supported by molecular docking studies. Two virulence proteins of FOL i.e., global transcription regulator (SGE1) and DNA binding transcription factor (STE12) were docked with identified phytocompounds in the chloroform fraction by GC/MS analysis. Both of the receptors showed maximum binding affinities with 2-[2-(4-Phenyl-piperidin-1-yl)-ethyl]-isoindole-1,3‑dione (PED) (-12.054 kcal/mol) and 3,5-di‑tert-Butyl-4-hydroxyphenylpropionic acid (BHP) (-13.327 kcal/mol) respectively with strong hydrophilic/phobic interactions with active pocket residues. In conclusion, the chloroform fraction of S. aromaticum can be used to manage FOL.

The functional and structural characterisation of the bZIP transcription factors from Myristica fragrans Houtt. associated to plant disease-resistant defence: An insight from transcriptomics and computational modelling

The bZIP transcription factors play crucial roles in various aspects of plant biology, including development, defence mechanisms, senescence, and responses to both biotic and abiotic environmental stresses. Myristica fragrans Houtt. transcriptome analysis has identified 15 bZIP transcription factors, each exhibiting major conserved domains and motifs such as BRLZ, MFMR, and DOG1. Functional characterisation of these identified MfbZIP factors indicates their predominant localisation within the nucleus. Phylogenetic analysis reveals that MfbZIP factors cluster into three subgroups alongside annotated bZIP sequences from Magnolia sinica and Arabidopsis thaliana. Moreover, gene ontology (GO) analysis highlights several key functions of MfbZIP, including involvement in defence responses, abscisic acid-induced signalling pathways, and DNA-binding transcription factor activity. Further investigation through KEGG pathway analysis reveals that the amino acid sequences of MfbZIP contain binding motifs for proteins such as TGA, implicated in plant hormone signal transduction pathways associated with disease resistance. To confirm the disease-defence-related activity of the TGA binding protein within MfbZIP, we employed amino acid sequences for 3-D ab initio modelling. Subsequently, we analysed TGA-NPR1 interactions using docking and molecular dynamics simulation analysis. These analyses shed light on the functional and structural aspects of TGA, demonstrating its stable association with NPR1 protein and its significance in the expression of PR1 protein, thus playing a pivotal role in defence responses against pathogens.

Study on the active components and mechanism of Atractylodis Macrocephalae Rhizoma for invigorating the spleen and tonifying qi based on spectrum-effect relationship and network pharmacology.

Spleen deficiency can lead to various abnormal physiological functions of the spleen. Atractylodis Macrocephalae Rhizoma (AMR) is a traditional Chinese medicine used to invigorate the spleen and tonify qi. The study aimed to identify the primary active components influencing the efficacy of AMR in strengthening the spleen and replenishing qi through spectrum-effect relationship and chemometrics. Network pharmacology was used to investigate the mechanism by which AMR strengthens the spleen and replenishes qi, with molecular docking utilized for validation purposes. The findings indicated that bran-fried AMR exhibited superior efficacy, with atractylenolides and atractylone identified as the primary active constituents. Atractylenolide II emerged as the most influential component impacting the effectiveness of AMR, while the key target was androgen receptor. Furthermore, crucial pathways implicated included the mitogen-activated protein cascade (MAPK) cascade, RNA polymerase II transcription factor activity, ligand-activated sequence-specific DNA binding, and RNA polymerase II sequence-specific DNA-binding transcription factor binding. In summary, our study has identified the primary active components associated with the efficacy of AMR and has provided an initial exploration of its mechanism of action. This offers a theoretical foundation for future investigations into the material basis and molecular mechanisms underlying the pharmacodynamics of AMR.

IFI35 regulates non-canonical NF-κB signaling to maintain glioblastoma stem cells and recruit tumor-associated macrophages.

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME. IFI35 induced non-canonical NF-kB signaling through proteasomal processing of p105 to the DNA-binding transcription factor p50, which heterodimerizes with RELB (RELB/p50), and activated cell chemotaxis in a cell-autonomous manner. Further, IFI35 induced recruitment and maintenance of M2-like TAMs in TME in a paracrine manner. Targeting IFI35 effectively suppressed in vivo tumor growth and prolonged survival of orthotopic xenograft-bearing mice. Collectively, these findings reveal the tumor-promoting functions of IFI35 and suggest that targeting IFI35 or its downstream effectors may provide effective approaches to improve GBM treatment.

Polymorphic locus rs8023580 NR2F2-AS1 is associated with breast cancer risk in residents of Central Russia

Breast cancer (BC) is the most common hormone-dependent genetically determined cancer among women. The level of “active” sex hormones in the body, the connection of which with breast cancer is beyond doubt, is determined by the content of the protein transporting sex hormones (SHBG).Aim: To study associations of polymorphic loci linked with the level of SHBG at the full-genomic level of significance with the risk of developing breast cancer.Material and Methods. The work was carried out on a sample of 1,498 women, 358 of whom were BC patients, the control was 1140 individuals. Genotyping of four single nucleotide polymorphic loci (SNP) associated with the level of SHBG was performed according to previously performed genome-wide studies (GWAS): rs7910927 JMJD1C, rs4149056 SLCO1B1, rs8023580 NR2F2-AS1, rs12150660 SHBG. The method of logistic regression was used to search for associations.Results and Discussion. SNP rs8023580 of the NR2F2-AS1 gene is associated with the risk of BC developing. The presence of the CC genotype rs8023580 NR2F2-AS1in a woman has a protective value in the formation of the disease (CCvsTC+TT [recessive model]; OR = 0.58; 95%CI = 0.35–0.96; p = 0.033; pperm = 0.042). SNP rs8023580 NR2F2-AS1 is functionally significant in the liver: it is localized in the enhancer region, affects the level of methylation of the cg01739960 (hg38) genome region, affects the expression of the RP11-327J17.2 gene, determines the interaction of DNA with six transcription factors (Fo xd1,Foxl1,Foxq1,Mef2,PLZF,STAT), which are located in the cis-regulatory region of RNA polymerase II, specific for the DNA binding sequence, and determine the activity of DNA-binding transcription factors specific for RNA polymerase II, are involved in the processes of cellular differentiation and tissue development.Conclusion. The SHBG-enhancing CC genotype rs8023580 of the NR2F2-AS1 gene is a protective factor in the development of BC.

Abstract LB194: Methylation subtypes of skull base chordoma

Abstract Background: Chordoma is a rare bone tumor with a high recurrence partially due to incomplete tumor resection. Recent studies suggest that chordoma is a heterogeneous disease that may comprise of molecular subtypes manifesting distinct clinical outcomes. Molecular classification may improve our knowledge of chordoma biology and patient stratification. However, due to its rareness, tumor profiling data is limited. The aim of this study was to identify molecular subtypes of chordoma that may improve clinical management using methylation profiling data. Methods: Genomic DNA was extracted from fresh frozen tissues in 67 patients with skull-base chordoma from Beijing Tiantian Hospital, China. DNA was then profiled using an Infinium Methylation 850K BeadChip array. CpG sites involving low-quality data (CpG detection with p > 0.01), those on the X and Y chromosomes, and the sites overlapping with single-nucleotide polymorphisms were removed. RNA sequencing (RNA-Seq) data was available for 51 out of 67 tumor samples. Results: We conducted unsupervised clustering analysis using the top 8000 most variable methylation probes and identified two distinct clusters (Cluster 1 n = 40, Cluster 2 n = 27). Thirty-three significant differentially methylated regions (DMRs, p-adj < 0.05) were identified between the two clusters using Bumphunter. Gene set enrichment analysis (GSEA) Hallmark analysis identified four enriched pathways of interest: IL6 JAK STAT3 Signaling, Mitotic Spindle, TGF Beta Signaling, and Apical Junction among genes included in these DMRs (p-adj < 0.05). We used RNA-Seq data to identify significant correlations between methylation probes and gene expression associated with DMR genes (n=30 genes; n=150 probes). We found probes in four genes of interest (HOXA3, MBP, NEDD4L, and TEX14) showed consistent negative correlations with gene expression levels. HOXA3 encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation in pathways that are highly relevant to chordoma development. Previous research has cited HOX complex inhibition in highly therapy resistant chordoma relapses. NEDD4L is associated with regulation of the epithelial NA+ channels and plays an important role in regulating tumor cell function through ubiquitinating substrates. MBP is involved in nervous system development, while the role of TEX14 in cancer is less understood. Conclusion: Our results confirmed findings from previous studies that chordoma is molecularly heterogeneous. In addition to immune pathways, we showed that the two subtypes also demonstrated different epigenetic regulation in mitosis and cell adhesion related genes/pathways. Next, we will expand the analysis by including more samples to increase statistical power and to associate our epigenetic findings with patient outcomes. Our goal is to build a reliable classifier to facilitate clinical management. We will integrate whole genome/exome sequencing data to identify potential epigenetic drivers. Citation Format: Gulzar N. Daya, Yujia Xiong, Mingxuan Li, Hela Koka, Xiaoyu Wang, DiFei Wang, Shilpa Katta, Jiwei Bai, Xiaohong R. Yang. Methylation subtypes of skull base chordoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB194.

TBCA: Prediction of transcription factor binding sites using a deep neural network with lightweight attention mechanism.

The identification of transcription factor binding sites (TFBSs) is crucial for understanding the regulatory mechanisms of gene expression, which contributes to unraveling cellular functions and disease development. Currently, the most common approach involves the use of deep learning techniques to predict TFBSs by combining sequence and shape features. Although significant progress has been made with these methods, the integration of local features extracted from DNA sequences and shapes with global features has not yet reached a sufficient level, and there is still significant room for improvement in the accuracy of prediction results. In this paper, we propose a novel framework based on convolution and attention mechanisms, referred to as TBCA, which combines DNA sequence information and shape information for predicting transcription factor binding sites. In this work, we employ a two-layer convolutional neural network (CNNs) and self-attention mechanism to extract complex sequence features from DNA. What's more, we utilize a Fourier-transform-enhanced multi-head attention along with channel attention to extract high-order shape features of DNA. Finally, these high-order sequence and shape features are integrated into the channel dimension to achieve accurate TFBSs prediction. Our research results demonstrate that TBCA exhibits superior predictive performance in 165 validated ChIP-seq datasets. Furthermore, the employed attention mechanisms can automatically learn important features at different positions and scales, enhancing the accuracy and robustness of feature representation. We also conduct an in-depth analysis of the contributions of five different shapes to site prediction, revealing that shape features can enhance the prediction of transcription factor DNA binding.

Single-cell multi-omics analysis identifies context-specific gene regulatory gates and mechanisms.

There is a growing interest in inferring context specific gene regulatory networks from single-cell RNA sequencing (scRNA-seq) data. This involves identifying the regulatory relationships between transcription factors (TFs) and genes in individual cells, and then characterizing these relationships at the level of specific cell types or cell states. In this study, we introduce scGATE (single-cell gene regulatory gate) as a novel computational tool for inferring TF-gene interaction networks and reconstructing Boolean logic gates involving regulatory TFs using scRNA-seq data. In contrast to current Boolean models, scGATE eliminates the need for individual formulations and likelihood calculations for each Boolean rule (e.g. AND, OR, XOR). By employing a Bayesian framework, scGATE infers the Boolean rule after fitting the model to the data, resulting in significant reductions in time-complexities for logic-based studies. We have applied assay for transposase-accessible chromatin with sequencing (scATAC-seq) data and TF DNA binding motifs to filter out non-relevant TFs in gene regulations. By integrating single-cell clustering with these external cues, scGATE is able to infer context specific networks. The performance of scGATE is evaluated using synthetic and real single-cell multi-omics data from mouse tissues and human blood, demonstrating its superiority over existing tools for reconstructing TF-gene networks. Additionally, scGATE provides a flexible framework for understanding the complex combinatorial and cooperative relationships among TFs regulating target genes by inferring Boolean logic gates among them.

Abstract 6589: Discovery of potent and selective pan-TEAD autopalmitoylation inhibitors for the treatment of Hippo-pathway altered cancers

Abstract TEAD1-4 are DNA bound transcription factors regulated by the Hippo tumor suppressor pathway that bind the coactivators YAP/TAZ to activate oncogenic gene expression programs involved in cell survival, proliferation, and drug resistance. TEAD-dependent transcription is activated in many tumor types through a variety of mechanisms including LOF Hippo pathway mutations (e.g. NF2, LATS) and YAP/TAZ amplification, and also as an adaptive resistance mechanism, for example in response to EGFR TKI and KRAS inhibition. Here, we report the initial characterization of a novel pan-TEAD inhibitor, AZ4331, which was identified following a structure-guided drug design campaign. AZ4331 disrupts the post-translational palmitoylation of TEAD proteins through covalent binding to a conserved cysteine residue resulting in inhibition of TEAD-dependent transcriptional output. AZ4331 inhibited the proliferation of NF2m NCI-H226 cells (GI50: 92 nM) while having no effect on Hippo-wild type NCI-H2452 (GI50: undetermined). Cell-based metabolic labeling studies demonstrated the ability of AZ4331 to inhibit palmitoylation of all four TEAD paralogs and led to disruption of the YAP/TEAD complex assessed by immunoprecipitation resulting in reduced TEAD transcriptional output as assessed by qPCR. Furthermore, in vivo profiling showed AZ4331 achieved sufficient exposures (plasma free Cmax: 2.7 µM) and robust target engagement as measured through reduction of multiple canonical TEAD target genes (CTGF [IC50: 0.127 µM], ANKRD1, AMOTL2 and CYR61) in Hippo-altered mesothelioma xenograft tumors. This target engagement in turn drove inhibition of tumor proliferation in xenograft models representing common Hippo-alterations. AZ4331 treatment of NF2m NCI-H226 and LATS1/2 loss MSTO-211H mesothelioma xenografts drove 50% and 93% regression of tumors, respectively. While treatment of head and neck squamous cell carcinoma FAT1m FaDu and YAP1amp Detroit562 xenografts lead to 58% tumor growth inhibition and 35% tumor regression, respectively. These findings identify AZ4331 as a potent inhibitor of the TEAD transcription factor family and further validate the inhibition of TEAD in Hippo-altered cancers as a potential therapeutic strategy. Citation Format: Jacob A. Gordon, Jolanta Dubauskaite, Michelle DuPont, Nin Guan, Geoff Holdgate, Scott Mlynarski, Neil Umbreit, Danielle Sanchez, Abhishek Srivastava, Janek Suski, Nancy Su, Ryan Richards, Sabina Cosulich, Corinne Reimer, James Brownell. Discovery of potent and selective pan-TEAD autopalmitoylation inhibitors for the treatment of Hippo-pathway altered cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6589.

Abstract 4892: MicroRNA signature and telomere genes in kidney cancer survival

Abstract Introduction: Kidney cancer ranks among the top 10 most prevalent cancers in the United States, clear cell renal cell carcinoma (ccRCC) has the worst disease specific survival histology. MicroRNAs (miRNAs) have emerged as potential prognostic indicators in various cancers, including kidney cancers. Telomerase, a biomarker associated with uncontrolled cancer cell growth, plays a crucial role in the human kidney cortex's telomere shortening over time. However, the link between miRNAs and telomeres in kidney cancer survival remains underexplored. Our study aims to uncover a miRNA signature capable of predicting 5-year survival in ccRCC patients and to investigate the biological relevance of this signature, particularly its shared pathway enrichment mechanisms with telomere genes. Methods: We extracted miRNA expression profiles from The Cancer Genome Atlas database, comprising 166 patients with ccRCC. To identify a robust miRNA signature predicting 5-year survival in ccRCC, we established an Evolutionary Kidney Survival Estimator (EKSE) using an optimal feature selection algorithm and support vector regression. Additionally, we conducted bioinformatics analyses to uncover common biological pathways between miRNAs and telomere genes using Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) categories, encompassing biological processes, molecular functions, and cellular components. Results: EKSE identified a robust signature consisting of 37 miRNAs, achieving a mean correlation coefficient and mean absolute error of 0.82±0.01 and 0.65±0.18, respectively between actual and estimated survival times. The top 10 ranked miRNAs in the signature, including hsa-miR-26a-1-3p, hsa-miR-28-5p, hsa-miR-3913-5p, hsa-miR-3170, hsa-miR-148a-5p, hsa-miR-671-3p, hsa-miR-224-3p, hsa-miR-10a-5p, hsa-miR-29b-1-5p, and hsa-miR-106b-5p, also showed promise in diagnosing ccRCC with AUC values ranging from 0.56 to 0.91. Furthermore, bioinformatics analysis revealed that the miRNA signature targeted well known telomere-associated genes such as TERT, DKC1, CTC1, and RTEL1. Notably, miRNA signature and telomere genes shared several common pathways, including cellular senescence (hsa04218) and proteoglycans in cancer (hsa05205). They also had overlapping GO-Molecular functions, such as DNA-binding transcription factor activity (GO:0003700), histone deacetylase binding (GO:0042826), and promoter-specific chromatin binding (GO:1990841). Conclusions: Our findings suggest an association between microRNAs and telomere genes, potentially playing significant roles in the survival of patients with ccRCC. The identified miRNA signature robustly predicts 5-year survival in ccRCC. The shared biological pathways between these miRNAs and telomere genes offer new insights into the mechanisms driving ccRCC, signaling potential for therapeutic targets and improved prognostic markers in kidney cancer. Citation Format: Srinivasulu Yerukala Sathipati, Rohit Sharma, Scott Hebbring. MicroRNA signature and telomere genes in kidney cancer survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4892.

Abstract 5019: Comprehensive pan-cancer analysis of cfDNA methylation marks in tumors reveals complex epigenetic regulatory circuits and diagnostic biomarkers

Abstract Early detection of tumor activity in clinically asymptomatic patients has the potential to improve quality of life and prevent unnecessary exposure to toxic therapies. DNA methylation is one of the most studied, stable, and fundamental epigenetic marks and represents a prominent alteration in most cancers. Analysis of DNA methylation, particularly in liquid biopsies has been introduced in cancer diagnosis and risk stratification. Despite indisputable achievements, translation into clinical practice is lagging behind, primarily due to 1) challenges associated with the analysis of DNA methylation, 2) the fragmented nature of cell-free DNA (cfDNA), aggravated by bisulfite treatment, 3) lack of clinical validation of reported cfDNA methylation marks, and 4) the paucity of knowledge about the functional consequences of cfDNA methylation marks within tumors. Using a sample pooling strategy, complemented with robust whole genome and reduced representation methylation sequencing, we establish a pan-cancer cfDNA methylation resource encompassing 12 cancer entities with diverse clinical phenotypes and treatment modalities. We built this compendium using a robustly performing whole genome and reduced representaion enzymatic methylation sequencing of more than 150 cfDNA and tumor DNA. We complement our data by analyzing DNA methylation data from 15 cancer entities (more than 7,000 patients) within the TCGA. We developed an enzymatic digital PCR (dPCR) approach for pan-cancer but also entity-specific analysis of cfDNA methylation at single base-resolution. Using this dPCR assay, we analyzed cfDNA and tumor DNA samples from more than 400 patients and compared enzymatic digestion with bisulfite treatment. We demonstrate that this resource can allow for the identification of entity-agnostic and specific markers, and that cfDNA methylation patterns are mirrored in tumor samples. The approach can be applied for methylation profiling of yet unanalyzed entities. Finally, we demonstrate unconventional epigenetic regulation of gene expression by methylated DNA-binding transcription factors whose activities are tissue- and context-specific and dosage-dependent. This work, therefore, provides a reference resource to identify minimally invasive, entity-specific and pan-cancer markers applicable for diagnostics, surveillance and patient stratification. It also sets the stage for further investigation of tissue- and context-specific epigenetic regulation of gene expression in health and disease by methylated DNA-binding transcription factors. Citation Format: Smiths Sengkwawoh Lueong, Martin Metzenmacher, Gregor Zaun, Gina Lauren Mayer, Erik Jan Hemmer, Katharina Lückerath, Kelsey Pomykala, Balazs Hegedüs, Peter A. Horn, Marija Trajkovic-Arsic, Tibor Szarvas, Renáta Váraljai, Corinna Keup, Ingeborg Tinhofer, Stephen George, Sabine Kasimir-Bauer, Samuel Peña-Llopis, Alexander Roesch, Cornelius Kürten, Lukas Boosfeld, Kirsten Bruderek, Christopher Darr, Thomas Hilser, Viktor Grünwald, Sven Brandau, Boris Hadaschik, Hans Neubauer, Irene Irene Esposito Irene Esposito, Tanja Fehm, Csilla Oláh, Anita Csizmarik, Fabinshy Thangarajah, Laura Reetz, Ghanam Jamal, Basant Kumar Thakur, Halime Kalkavan, Alexander Schramm, Martin Schuler, Jens T. Siveke. Comprehensive pan-cancer analysis of cfDNA methylation marks in tumors reveals complex epigenetic regulatory circuits and diagnostic biomarkers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5019.