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223


Universal receptive system as a novel regulator of transcriptomic activity of Staphylococcus aureus

Tetz, George; Kardava, Kristina; Vecherkovskaya, Maria; Khodadadi-Jamayran, Alireza; Tsirigos, Aristotelis; Tetz, Victor
Our previous studies revealed the existence of a Universal Receptive System that regulates interactions between cells and their environment. This system is composed of DNA- and RNA-based Teazeled receptors (TezRs) found on the surface of prokaryotic and eukaryotic cells, as well as integrases and recombinases. In the current study, we aimed to provide further insight into the regulatory role of TezR and its loss in Staphylococcus aureus gene transcription. To this end, transcriptomic analysis of S. aureus MSSA VT209 was performed following the destruction of TezRs. Bacterial RNA samples were extracted from nuclease-treated and untreated S. aureus MSSA VT209. After destruction of the DNA-based-, RNA-, or combined DNA- and RNA-based TezRs of S. aureus, 103, 150, and 93 genes were significantly differently expressed, respectively. The analysis revealed differential clustering of gene expression following the loss of different TezRs, highlighting individual cellular responses following the loss of DNA- and RNA-based TezRs. KEGG pathway gene enrichment analysis revealed that the most upregulated pathways following TezR inactivation included those related to energy metabolism, cell wall metabolism, and secretion systems. Some of the genetic pathways were related to the inhibition of biofilm formation and increased antibiotic resistance, and we confirmed this at the phenotypic level using in vitro studies. The results of this study add another line of evidence that the Universal Receptive System plays an important role in cell regulation, including cell responses to the environmental factors of clinically important pathogens, and that nucleic acid-based TezRs are functionally active parts of the extrabiome.
PMID: 39754239
ISSN: 1475-2859
CID: 5781912

3D chromatin hubs as regulatory units of identity and survival in human acute leukemia

Gambi, Giovanni; Boccalatte, Francesco; Rodriguez Hernaez, Javier; Lin, Ziyan; Nadorp, Bettina; Polyzos, Alexander; Tan, Jimin; Avrampou, Kleopatra; Inghirami, Giorgio; Kentsis, Alex; Apostolou, Effie; Aifantis, Iannis; Tsirigos, Aristotelis
Cancer progression involves genetic and epigenetic changes that disrupt chromatin 3D organization, affecting enhancer-promoter interactions and promoting growth. Here, we provide an integrative approach, combining chromatin conformation, accessibility, and transcription analysis, validated by in silico and CRISPR-interference screens, to identify relevant 3D topologies in pediatric T cell leukemia (T-ALL and ETP-ALL). We characterize 3D hubs as regulatory centers for oncogenes and disease markers, linking them to biological processes like cell division, inflammation, and stress response. Single-cell mapping reveals heterogeneous gene activation in discrete epigenetic clones, aiding in patient stratification for relapse risk after chemotherapy. Finally, we identify MYB as a 3D hub regulator in leukemia cells and show that the targeting of key regulators leads to hub dissolution, thereby providing a novel and effective anti-leukemic strategy. Overall, our work demonstrates the relevance of studying oncogenic 3D hubs to better understand cancer biology and tumor heterogeneity and to propose novel therapeutic strategies.
PMID: 39719705
ISSN: 1097-4164
CID: 5767452

MetFinder: A Tool for Automated Quantitation of Metastatic Burden in Histological Sections From Preclinical Models

Karz, Alcida; Coudray, Nicolas; Bayraktar, Erol; Galbraith, Kristyn; Jour, George; Shadaloey, Arman Alberto Sorin; Eskow, Nicole; Rubanov, Andrey; Navarro, Maya; Moubarak, Rana; Baptiste, Gillian; Levinson, Grace; Mezzano, Valeria; Alu, Mark; Loomis, Cynthia; Lima, Daniel; Rubens, Adam; Jilaveanu, Lucia; Tsirigos, Aristotelis; Hernando, Eva
As efforts to study the mechanisms of melanoma metastasis and novel therapeutic approaches multiply, researchers need accurate, high-throughput methods to evaluate the effects on tumor burden resulting from specific interventions. We show that automated quantification of tumor content from whole slide images is a compelling solution to assess in vivo experiments. In order to increase the outflow of data collection from preclinical studies, we assembled a large dataset with annotations and trained a deep neural network for the quantitative analysis of melanoma tumor content on histopathological sections of murine models. After assessing its performance in segmenting these images, the tool obtained consistent results with an orthogonal method (bioluminescence) of measuring metastasis in an experimental setting. This AI-based algorithm, made freely available to academic laboratories through a web-interface called MetFinder, promises to become an asset for melanoma researchers and pathologists interested in accurate, quantitative assessment of metastasis burden.
PMID: 39254030
ISSN: 1755-148x
CID: 5690152

Dramatic Clinical Response to a Novel Form of Cell Therapy SL-28 in a Patient with Prostate Cancer and Bone Metastasis: A Case Report [Case Report]

Tetz, Victor; Kardava, Kristina; Shulenbayev, Olzhas; Vecherkovskaya, Maria; Khodadadi-Jamayran, Alireza; Tsirigos, Aristotelis; Tetz, George
PURPOSE/UNASSIGNED:Prostate cancer is the most common malignancy among older man and often a challenge owing to its rapid spread and age-related comorbidities. SL-28 (Leukocyte-Tells) is a novel cell therapy that uses allogeneic leukocytes whose anticancer activity is altered ex vivo using the recently discovered Universal Receptive System. PATIENTS AND METHODS/UNASSIGNED:A 79-year-old man with Т2сNOMx1, Gleason 7 (3+4) adenocarcinoma of the prostate, with a total PSA level of 10.6 ng/mL and free PSA:total PSA ratio of 11.4% received hormone therapy. Due to an insufficient clinical response and poor tolerance to the therapy, the patient underwent novel allogeneic SL-28 cell therapy. RESULTS/UNASSIGNED:SL-28 therapy was well-tolerated, with no serious adverse effects. The levels of laboratory markers of prostate cancer, such as prostate-specific antigen, gradually improved from the second week of SL-28 therapy. Complete responses, including the resolution of bone metastasis within 4 months of therapy, were confirmed by computed tomography and histology. CONCLUSION/UNASSIGNED: SL-28 was efficient and safe approach in a patient with stage IV prostate cancer, supporting its potential in an allogeneic cell therapy for advanced malignancies.
PMCID:12579837
PMID: 41185720
ISSN: 2253-1556
CID: 5959592

Lung microbial and host genomic signatures as predictors of prognosis in early-stage adenocarcinoma

Tsay, Jun-Chieh J; Darawshy, Fares; Wang, Chan; Kwok, Benjamin; Wong, Kendrew K; Wu, Benjamin G; Sulaiman, Imran; Zhou, Hua; Isaacs, Bradley; Kugler, Matthias C; Sanchez, Elizabeth; Bain, Alexander; Li, Yonghua; Schluger, Rosemary; Lukovnikova, Alena; Collazo, Destiny; Kyeremateng, Yaa; Pillai, Ray; Chang, Miao; Li, Qingsheng; Vanguri, Rami S; Becker, Anton S; Moore, William H; Thurston, George; Gordon, Terry; Moreira, Andre L; Goparaju, Chandra M; Sterman, Daniel H; Tsirigos, Aristotelis; Li, Huilin; Segal, Leopoldo N; Pass, Harvey I
BACKGROUND:Risk of early-stage lung adenocarcinoma (LUAD) recurrence after surgical resection is significant, and post-recurrence median survival is approximately two years. Currently there are no commercially available biomarkers that predict recurrence. Here, we investigated whether microbial and host genomic signatures in the lung can predict recurrence. METHODS:In 91 early-stage (Stage IA/IB) LUAD-patients with extensive follow-up, we used 16s rRNA gene sequencing and host RNA-sequencing to map the microbial and host transcriptomic landscape in tumor and adjacent unaffected lung samples. RESULTS:23 out of 91 subjects had tumor recurrence over 5-year period. In tumor samples, LUAD recurrence was associated with enrichment with Dialister, Prevotella, while in unaffected lung, recurrence was associated with enrichment with Sphyngomonas and Alloiococcus. The strengths of the associations between microbial and host genomic signatures with LUAD recurrence were greater in adjacent unaffected lung samples than in the primary tumor. Among microbial-host features in the unaffected lung samples associated with recurrence, enrichment with Stenotrophomonas geniculata and Chryseobacterium were positively correlated with upregulation of IL-2, IL-3, IL-17, EGFR, HIF-1 signaling pathways among the host transcriptome. In tumor samples, enrichment with Veillonellaceae Dialister, Ruminococcacea, Haemophilus Influenza, and Neisseria were positively correlated with upregulation of IL-1, IL-6, IL17, IFN, and Tryptophan metabolism pathways. CONCLUSIONS:Overall, modeling suggested that a combined microbial/transcriptome approach using unaffected lung samples had the best biomarker performance (AUC=0.83). IMPACT/CONCLUSIONS:This study suggests that LUAD recurrence is associated with distinct pathophysiological mechanisms of microbial-host interactions in the unaffected lung rather than those present in the resected tumor.
PMID: 39225784
ISSN: 1538-7755
CID: 5687792

The stress response regulator HSF1 modulates natural killer cell anti-tumour immunity

Hockemeyer, Kathryn; Sakellaropoulos, Theodore; Chen, Xufeng; Ivashkiv, Olha; Sirenko, Maria; Zhou, Hua; Gambi, Giovanni; Battistello, Elena; Avrampou, Kleopatra; Sun, Zhengxi; Guillamot, Maria; Chiriboga, Luis; Jour, George; Dolgalev, Igor; Corrigan, Kate; Bhatt, Kamala; Osman, Iman; Tsirigos, Aristotelis; Kourtis, Nikos; Aifantis, Iannis
Diverse cellular insults converge on activation of the heat shock factor 1 (HSF1), which regulates the proteotoxic stress response to maintain protein homoeostasis. HSF1 regulates numerous gene programmes beyond the proteotoxic stress response in a cell-type- and context-specific manner to promote malignancy. However, the role(s) of HSF1 in immune populations of the tumour microenvironment remain elusive. Here, we leverage an in vivo model of HSF1 activation and single-cell transcriptomic tumour profiling to show that augmented HSF1 activity in natural killer (NK) cells impairs cytotoxicity, cytokine production and subsequent anti-tumour immunity. Mechanistically, HSF1 directly binds and regulates the expression of key mediators of NK cell effector function. This work demonstrates that HSF1 regulates the immune response under the stress conditions of the tumour microenvironment. These findings have important implications for enhancing the efficacy of adoptive NK cell therapies and for designing combinatorial strategies including modulators of NK cell-mediated tumour killing.
PMID: 39223375
ISSN: 1476-4679
CID: 5687692

Members of an array of zinc-finger proteins specify distinct Hox chromatin boundaries

Ortabozkoyun, Havva; Huang, Pin-Yao; Gonzalez-Buendia, Edgar; Cho, Hyein; Kim, Sang Y; Tsirigos, Aristotelis; Mazzoni, Esteban O; Reinberg, Danny
Partitioning of repressive from actively transcribed chromatin in mammalian cells fosters cell-type-specific gene expression patterns. While this partitioning is reconstructed during differentiation, the chromatin occupancy of the key insulator, CCCTC-binding factor (CTCF), is unchanged at the developmentally important Hox clusters. Thus, dynamic changes in chromatin boundaries must entail other activities. Given its requirement for chromatin loop formation, we examined cohesin-based chromatin occupancy without known insulators, CTCF and Myc-associated zinc-finger protein (MAZ), and identified a family of zinc-finger proteins (ZNFs), some of which exhibit tissue-specific expression. Two such ZNFs foster chromatin boundaries at the Hox clusters that are distinct from each other and from MAZ. PATZ1 was critical to the thoracolumbar boundary in differentiating motor neurons and mouse skeleton, while ZNF263 contributed to cervicothoracic boundaries. We propose that these insulating activities act with cohesin, alone or combinatorially, with or without CTCF, to implement precise positional identity and cell fate during development.
PMID: 39173638
ISSN: 1097-4164
CID: 5681022

Characterization of tumor heterogeneity through segmentation-free representation learning

Tan, Jimin; Le, Hortense; Deng, Jiehui; Liu, Yingzhuo; Hao, Yuan; Hollenberg, Michelle; Liu, Wenke; Wang, Joshua M; Xia, Bo; Ramaswami, Sitharam; Mezzano, Valeria; Loomis, Cynthia; Murrell, Nina; Moreira, Andre L; Cho, Kyunghyun; Pass, Harvey; Wong, Kwok-Kin; Ban, Yi; Neel, Benjamin G; Tsirigos, Aristotelis; Fenyƶ, David
The interaction between tumors and their microenvironment is complex and heterogeneous. Recent developments in high-dimensional multiplexed imaging have revealed the spatial organization of tumor tissues at the molecular level. However, the discovery and thorough characterization of the tumor microenvironment (TME) remains challenging due to the scale and complexity of the images. Here, we propose a self-supervised representation learning framework, CANVAS, that enables discovery of novel types of TMEs. CANVAS is a vision transformer that directly takes high-dimensional multiplexed images and is trained using self-supervised masked image modeling. In contrast to traditional spatial analysis approaches which rely on cell segmentations, CANVAS is segmentation-free, utilizes pixel-level information, and retains local morphology and biomarker distribution information. This approach allows the model to distinguish subtle morphological differences, leading to precise separation and characterization of distinct TME signatures. We applied CANVAS to a lung tumor dataset and identified and validated a monocytic signature that is associated with poor prognosis.
PMID: 39282296
ISSN: 2692-8205
CID: 5958172

Digital spatial profiling to predict recurrence in grade 3 stage I lung adenocarcinoma

Chang, Stephanie H; Mezzano-Robinson, Valeria; Zhou, Hua; Moreira, Andre; Pillai, Raymond; Ramaswami, Sitharam; Loomis, Cynthia; Heguy, Adriana; Tsirigos, Aristotelis; Pass, Harvey I
OBJECTIVE:Early-stage lung adenocarcinoma is treated with local therapy alone, although patients with grade 3 stage I lung adenocarcinoma have a 50% 5-year recurrence rate. Our objective is to determine if analysis of the tumor microenvironment can create a predictive model for recurrence. METHODS:Thirty-four patients with grade 3 stage I lung adenocarcinoma underwent surgical resection. Digital spatial profiling was used to perform genomic (n = 31) and proteomic (n = 34) analyses of pancytokeratin positive and negative tumor cells. K-means clustering was performed on the top 50 differential genes and top 20 differential proteins, with Kaplan-Meier recurrence curves based on patient clustering. External validation of high-expression genes was performed with Kaplan-Meier plotter. RESULTS:There were no significant clinicopathologic differences between patients who did (n = 14) and did not (n = 20) have recurrence. Median time to recurrence was 806 days; median follow-up with no recurrence was 2897 days. K-means clustering of pancytokeratin positive genes resulted in a model with a Kaplan-Meier curve with concordance index of 0.75. K-means clustering for pancytokeratin negative genes was less successful at differentiating recurrence (concordance index 0.6). Genes upregulated or downregulated for recurrence were externally validated using available public databases. Proteomic data did not reach statistical significance but did internally validate the genomic data described. CONCLUSIONS:Genomic difference in lung adenocarcinoma may be able to predict risk of recurrence. After further validation, stratifying patients by this risk may help guide who will benefit from adjuvant therapy.
PMID: 37890657
ISSN: 1097-685x
CID: 5620342

Clonal evolution of the 3D chromatin landscape in patients with relapsed pediatric B-cell acute lymphoblastic leukemia

Narang, Sonali; Ghebrechristos, Yohana; Evensen, Nikki A; Murrell, Nina; Jasinski, Sylwia; Ostrow, Talia H; Teachey, David T; Raetz, Elizabeth A; Lionnet, Timothee; Witkowski, Matthew; Aifantis, Iannis; Tsirigos, Aristotelis; Carroll, William L
Relapsed pediatric B-cell acute lymphoblastic leukemia (B-ALL) remains one of the leading causes of cancer mortality in children. We performed Hi-C, ATAC-seq, and RNA-seq on 12 matched diagnosis/relapse pediatric leukemia specimens to uncover dynamic structural variants (SVs) and 3D chromatin rewiring that may contribute to relapse. While translocations are assumed to occur early in leukemogenesis and be maintained throughout progression, we discovered novel, dynamic translocations and confirmed several fusion transcripts, suggesting functional and therapeutic relevance. Genome-wide chromatin remodeling was observed at all organizational levels: A/B compartments, TAD interactivity, and chromatin loops, including some loci shared by 25% of patients. Shared changes were found to drive the expression of genes/pathways previously implicated in resistance as well as novel therapeutic candidates, two of which (ATXN1 and MN1) we functionally validated. Overall, these results demonstrate chromatin reorganization under the selective pressure of therapy and offer the potential for discovery of novel therapeutic interventions.
PMCID:11358475
PMID: 39198446
ISSN: 2041-1723
CID: 5701942