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Molecular Cancer Apr 2023Extranodal natural killer/T-cell lymphoma (NKTL) is an aggressive type of non-Hodgkin lymphoma with dismal outcome. A better understanding of disease biology and key...
BACKGROUND
Extranodal natural killer/T-cell lymphoma (NKTL) is an aggressive type of non-Hodgkin lymphoma with dismal outcome. A better understanding of disease biology and key oncogenic process is necessary for the development of targeted therapy. Super-enhancers (SEs) have been shown to drive pivotal oncogenes in various malignancies. However, the landscape of SEs and SE-associated oncogenes remain elusive in NKTL.
METHODS
We used Nano-ChIP-seq of the active enhancer marker histone H3 lysine 27 acetylation (H3K27ac) to profile unique SEs NKTL primary tumor samples. Integrative analysis of RNA-seq and survival data further pinned down high value, novel SE oncogenes. We utilized shRNA knockdown, CRISPR-dCas9, luciferase reporter assay, ChIP-PCR to investigate the regulation of transcription factor (TF) on SE oncogenes. Multi-color immunofluorescence (mIF) staining was performed on an independent cohort of clinical samples. Various function experiments were performed to evaluate the effects of TOX2 on the malignancy of NKTL in vitro and in vivo.
RESULTS
SE landscape was substantially different in NKTL samples in comparison with normal tonsils. Several SEs at key transcriptional factor (TF) genes, including TOX2, TBX21(T-bet), EOMES, RUNX2, and ID2, were identified. We confirmed that TOX2 was aberrantly overexpressed in NKTL relative to normal NK cells and high expression of TOX2 was associated with worse survival. Modulation of TOX2 expression by shRNA, CRISPR-dCas9 interference of SE function impacted on cell proliferation, survival and colony formation ability of NKTL cells. Mechanistically, we found that RUNX3 regulates TOX2 transcription by binding to the active elements of its SE. Silencing TOX2 also impaired tumor formation of NKTL cells in vivo. Metastasis-associated phosphatase PRL-3 has been identified and validated as a key downstream effector of TOX2-mediated oncogenesis.
CONCLUSIONS
Our integrative SE profiling strategy revealed the landscape of SEs, novel targets and insights into molecular pathogenesis of NKTL. The RUNX3-TOX2-SE-TOX2-PRL-3 regulatory pathway may represent a hallmark of NKTL biology. Targeting TOX2 could be a valuable therapeutic intervene for NKTL patients and warrants further study in clinic.
Topics: Humans; Cell Transformation, Neoplastic; Oncogenes; Transcription Factors; Lymphoma, Extranodal NK-T-Cell; RNA, Small Interfering; Killer Cells, Natural; Cell Line, Tumor; HMGB Proteins
PubMed: 37032358
DOI: 10.1186/s12943-023-01767-1 -
Biomedicine & Pharmacotherapy =... Sep 2023Cardiovascular disease (CVD) is the most fatal disease that causes sudden death, and inflammation contributes substantially to its occurrence and progression. The... (Review)
Review
Cardiovascular disease (CVD) is the most fatal disease that causes sudden death, and inflammation contributes substantially to its occurrence and progression. The prevalence of CVD increases as the population ages, and the pathophysiology is complex. Anti-inflammatory and immunological modulation are the potential methods for CVD prevention and treatment. High-Mobility Group (HMG) chromosomal proteins are one of the most abundant nuclear nonhistone proteins which act as inflammatory mediators in DNA replication, transcription, and repair by producing cytokines and serving as damage-associated molecular patterns in inflammatory responses. The most common and well-studied HMG proteins are those with an HMGB domain, which participate in a variety of biological processes. HMGB1 and HMGB2 were the first members of the HMGB family to be identified and are present in all investigated eukaryotes. Our review is primarily concerned with the involvement of HMGB1 and HMGB2 in CVD. The purpose of this review is to provide a theoretical framework for diagnosing and treating CVD by discussing the structure and function of HMGB1 and HMGB2.
Topics: Humans; HMGB1 Protein; HMGB2 Protein; Cardiovascular Diseases; HMGB Proteins; Biomarkers
PubMed: 37437373
DOI: 10.1016/j.biopha.2023.115118 -
Advanced Science (Weinheim,... May 2023Endothelial dysfunction is considered a predominant driver for pulmonary vascular remodeling in pulmonary hypertension (PH). SOX17, a key regulator of vascular...
Endothelial dysfunction is considered a predominant driver for pulmonary vascular remodeling in pulmonary hypertension (PH). SOX17, a key regulator of vascular homoeostasis, has been found to harbor mutations in PH patients, which are associated with PH susceptibility. Here, this study explores whether SOX17 mediates the autocrine activity of pulmonary artery ECs to maintain endothelial function and vascular homeostasis in PH and its underlying mechanism. It is found that SOX17 expression is downregulated in the endothelium of remodeled pulmonary arteries in IPH patients and SU5416/hypoxia (Su/hypo)-induced PH mice as well as dysfunctional HPAECs. Endothelial knockdown of SOX17 accelerates the progression of Su/hypo-induced PH in mice. SOX17 overexpression in the pulmonary endothelium of mice attenuates Su/hypo-induced PH. SOX17-associated exosomes block the proliferation, apoptosis, and inflammation of HPAECs, preventing pulmonary arterial remodeling and Su/hypo-induced PH. Mechanistic analyses demonstrates that overexpressing SOX17 promotes the exosome-mediated release of miR-224-5p and miR-361-3p, which are internalized by injured HPAECs in an autocrine manner, ultimately repressing the upregulation of NR4A3 and PCSK9 genes and improving endothelial function. These results suggest that SOX17 is a key gene in maintaining endothelial function and vascular homeostasis in PH through regulating exosomal miRNAs in an autocrine manner.
Topics: Animals; Humans; Mice; Endothelial Cells; Endothelium; Exosomes; HMGB Proteins; Hypertension, Pulmonary; Hypoxia; MicroRNAs; Proprotein Convertase 9; SOXF Transcription Factors
PubMed: 36919784
DOI: 10.1002/advs.202206139 -
Circulation May 2023Pulmonary arterial hypertension (PAH) is a rare disease characterized by remodeling of the pulmonary arteries, increased vascular resistance, and right-sided heart...
BACKGROUND
Pulmonary arterial hypertension (PAH) is a rare disease characterized by remodeling of the pulmonary arteries, increased vascular resistance, and right-sided heart failure. Genome-wide association studies of idiopathic/heritable PAH established novel genetic risk variants, including conserved enhancers upstream of transcription factor (TF) containing 2 independent signals. SOX17 is an important TF in embryonic development and in the homeostasis of pulmonary artery endothelial cells (hPAEC) in the adult. Rare pathogenic mutations in cause heritable PAH. We hypothesized that PAH risk alleles in an enhancer region impair TF-binding upstream of , which in turn reduces expression and contributes to disturbed endothelial cell function and PAH development.
METHODS
CRISPR manipulation and siRNA were used to modulate expression. Electromobility shift assays were used to confirm in silicopredicted TF differential binding to the variants. Functional assays in hPAECs were used to establish the biological consequences of loss. In silico analysis with the connectivity map was used to predict compounds that rescue disturbed signaling. Mice with deletion of the -signal 1 enhancer region (-4593/enhKO) were phenotyped in response to chronic hypoxia and SU5416/hypoxia.
RESULTS
CRISPR inhibition of -signal 2 and deletion of -signal 1 specifically decreased expression. Electromobility shift assays demonstrated differential binding of hPAEC nuclear proteins to the risk and nonrisk alleles from both signals. Candidate TFs HOXA5 and ROR-α were identified through in silico analysis and antibody electromobility shift assays. Analysis of the hPAEC transcriptomes revealed alteration of PAH-relevant pathways on silencing, including extracellular matrix regulation. silencing in hPAECs resulted in increased apoptosis, proliferation, and disturbance of barrier function. With the use of the connectivity map, compounds were identified that reversed the SOX17-dysfunction transcriptomic signatures in hPAECs. enhancer knockout in mice reduced lung SOX17 expression, resulting in more severe pulmonary vascular leak and hypoxia or SU5416/hypoxia-induced pulmonary hypertension.
CONCLUSIONS
Common PAH risk variants upstream of the promoter reduce endothelial expression, at least in part, through differential binding of HOXA5 and ROR-α. Reduced SOX17 expression results in disturbed hPAEC function and PAH. Existing drug compounds can reverse the disturbed SOX17 pulmonary endothelial transcriptomic signature.
Topics: Mice; Animals; Hypertension, Pulmonary; Genome-Wide Association Study; Endothelial Cells; Pulmonary Arterial Hypertension; Pulmonary Artery; Hypoxia; Familial Primary Pulmonary Hypertension; Transcription Factors; HMGB Proteins; SOXF Transcription Factors
PubMed: 37066790
DOI: 10.1161/CIRCULATIONAHA.122.061940 -
American Journal of Respiratory and... Apr 2023Genetic studies suggest that SOX17 (SRY-related HMG-box 17) deficiency increases pulmonary arterial hypertension (PAH) risk. On the basis of pathological roles of...
Genetic studies suggest that SOX17 (SRY-related HMG-box 17) deficiency increases pulmonary arterial hypertension (PAH) risk. On the basis of pathological roles of estrogen and HIF2α (hypoxia-inducible factor 2α) signaling in pulmonary artery endothelial cells (PAECs), we hypothesized that SOX17 is a target of estrogen signaling that promotes mitochondrial function and attenuates PAH development via HIF2α inhibition. We used metabolic (Seahorse) and promoter luciferase assays in PAECs together with the chronic hypoxia murine model to test the hypothesis. Sox17 expression was reduced in PAH tissues (rodent models and from patients). Chronic hypoxic pulmonary hypertension was exacerbated by mice with conditional Tie2- () deletion and attenuated by transgenic Tie2- overexpression (). On the basis of untargeted proteomics, metabolism was the top pathway altered by SOX17 deficiency in PAECs. Mechanistically, we found that HIF2α concentrations were increased in the lungs of and reduced in those from mice. Increased SOX17 promoted oxidative phosphorylation and mitochondrial function in PAECs, which were partly attenuated by HIF2α overexpression. Rat lungs in males displayed higher Sox17 expression versus females, suggesting repression by estrogen signaling. Supporting 16α-hydroxyestrone (16αOHE; a pathologic estrogen metabolite)-mediated repression of promoter activity, mice attenuated 16αOHE-mediated exacerbations of chronic hypoxic pulmonary hypertension. Finally, in adjusted analyses in patients with PAH, we report novel associations between a risk variant, rs10103692, and reduced plasma citrate concentrations ( = 1,326). Cumulatively, SOX17 promotes mitochondrial bioenergetics and attenuates PAH, in part, via inhibition of HIF2α. 16αOHE mediates PAH development via downregulation of SOX17, linking sexual dimorphism and genetics in PAH.
Topics: Male; Rats; Female; Mice; Animals; Hypertension, Pulmonary; Endothelial Cells; Lung; Pulmonary Artery; Hypoxia; Estrogens; Pulmonary Arterial Hypertension; Familial Primary Pulmonary Hypertension; HMGB Proteins; SOXF Transcription Factors
PubMed: 36913491
DOI: 10.1164/rccm.202203-0450OC -
International Journal of Molecular... Oct 2020The functioning of DNA in the cell nucleus is ensured by a multitude of proteins, whose interactions with DNA as well as with other proteins lead to the formation of a... (Review)
Review
The functioning of DNA in the cell nucleus is ensured by a multitude of proteins, whose interactions with DNA as well as with other proteins lead to the formation of a complicated, organized, and quite dynamic system known as chromatin. This review is devoted to the description of properties and structure of the progenitors of the most abundant non-histone protein of the HMGB family-the HmgB1 protein. The proteins of the HMGB family are also known as "architectural factors" of chromatin, which play an important role in gene expression, transcription, DNA replication, and repair. However, as soon as HmgB1 goes outside the nucleus, it acquires completely different functions, post-translational modifications, and change of its redox state. Despite a lot of evidence of the functional activity of HmgB1, there are still many issues to be solved related to the mechanisms of the influence of HmgB1 on the development and treatment of different diseases-from oncological and cardiovascular diseases to pathologies during pregnancy and childbirth. Here, we describe molecular structure of the HmgB1 protein and discuss general mechanisms of its interactions with other proteins and DNA in cell.
Topics: Animals; Cardiovascular Diseases; Chromatin; DNA; DNA Repair; DNA Replication; Gene Expression Regulation; HMGB1 Protein; Humans; Neoplasms; Protein Processing, Post-Translational; Transcription, Genetic
PubMed: 33114717
DOI: 10.3390/ijms21217948 -
Cancer Research Jun 2020Chromatin-associated architectural proteins are part of a fundamental support system for cellular DNA-dependent processes and can maintain/modulate the efficiency of DNA... (Review)
Review
Chromatin-associated architectural proteins are part of a fundamental support system for cellular DNA-dependent processes and can maintain/modulate the efficiency of DNA replication, transcription, and DNA repair. Interestingly, prognostic outcomes of many cancer types have been linked with the expression levels of several of these architectural proteins. The high mobility group box (HMGB) architectural protein family has been well studied in this regard. The differential expression levels of HMGB proteins and/or mRNAs and their implications in cancer etiology and prognosis present the potential of novel targets that can be explored to increase the efficacy of existing cancer therapies. HMGB1, the most studied member of the HMGB protein family, has pleiotropic roles in cells including an association with nucleotide excision repair, base excision repair, mismatch repair, and DNA double-strand break repair. Moreover, the HMGB proteins have been identified in regulating DNA damage responses and cell survival following treatment with DNA-damaging agents and, as such, may play roles in modulating the efficacy of chemotherapeutic drugs by modulating DNA repair pathways. Here, we discuss the functions of HMGB proteins in DNA damage processing and their potential roles in cancer etiology, prognosis, and therapeutics.
Topics: Animals; Chromosomes; DNA Damage; DNA Repair; HMGB Proteins; Humans; Molecular Targeted Therapy; Neoplasms
PubMed: 32152151
DOI: 10.1158/0008-5472.CAN-19-3066 -
Frontiers in Immunology 2020
Topics: Disease Susceptibility; Drug Discovery; Gene Expression Regulation; HMGB1 Protein; Humans; Immunity; Immunomodulation; Protein Processing, Post-Translational; Signal Transduction
PubMed: 33013940
DOI: 10.3389/fimmu.2020.594253 -
Biochimica Et Biophysica Acta 2010High mobility group (HMG) proteins assume important roles in regulating chromatin dynamics, transcriptional activities of genes and other cellular processes.... (Review)
Review
High mobility group (HMG) proteins assume important roles in regulating chromatin dynamics, transcriptional activities of genes and other cellular processes. Post-translational modifications of HMG proteins can alter their interactions with DNA and proteins, and consequently, affect their biological activities. Although the mechanisms through which these modifications are involved in regulating biological processes in different cellular contexts are not fully understood, new insights into these modification "codes" have emerged from the increasing appreciation of the functions of these proteins. In this review, we focus on the chemical modifications of mammalian HMG proteins and highlight their roles in nuclear functions.
Topics: Amino Acid Sequence; Animals; Cell Nucleus; HMGA Proteins; HMGB Proteins; HMGN Proteins; High Mobility Group Proteins; Humans; Molecular Sequence Data; Protein Processing, Post-Translational
PubMed: 20123066
DOI: 10.1016/j.bbagrm.2009.11.009 -
Molekuliarnaia Biologiia 2018HMGB proteins are involved in structural rearrangements caused by regulatory chromatin remodeling factors. Particular interest is attracted to a DNA chaperone mechanism,... (Review)
Review
HMGB proteins are involved in structural rearrangements caused by regulatory chromatin remodeling factors. Particular interest is attracted to a DNA chaperone mechanism, suggesting that the HMGB proteins introduce bends into the double helix, thus rendering DNA accessible to effector proteins and facilitating their activity. The review discusses the role that the HMBG proteins play in key intranuclear processes, including assembly of the preinitiation complex during transcription of ribosomal genes; transcription by RNA polymerases I, II, and III; recruitment of the SWI/SNF complex during transcription of nonribosomal genes; DNA repair; etc. The functions of the HMGB proteins are considered in detail with the examples of yeast HMO1 and NHP6. The two proteins possess unique features in adition to properties characteristic of the HMGB proteins. Thus, NHP6 stimulates a large-scale ATP-independent unwrapping of nucleosomal DNA by the FACT complex, while in its absence FACT stabilizes the nucleosome. HMO1 acts as an alternative linker histone. Both HMO1 and NHP6 are of applied interest primarly because they are homologs of human HMGB1, an important therapeutic target of anticancer and anti-inflammatory treatments.
Topics: Chromatin; DNA; HMGB Proteins; HMGN Proteins; High Mobility Group Proteins; Histones; Humans; Molecular Chaperones; Nucleosomes; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins
PubMed: 30363049
DOI: 10.1134/S0026898418050099