Receptor Binding SET Domain Protein Research Articles

NSD2-mediated H3K36me2 exacerbates osteoporosis via activation of hoxa2 in bone marrow mesenchymal stem cells

BackgroundOsteoporosis (OP) is a prevalent disease associated with age, and one of the primary pathologies is the defect of osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). This study aimed to elucidate whether Nuclear Receptor Binding SET Domain Protein 2 (NSD2) transcriptionally regulates osteogenic differentiation of BMSCs in osteoporosis. MethodsIdentification of human BMSCs (hBMSCs) in vitro was measured by flow cytometry. Osteogenesis of hBMSCs in vitro was measured by Alizarin Red and Alkaline Phosphatase staining. The protein levels of H3K36me1/2/3, NSD2, and Hoxa2 were measured by western blotting. The mRNA levels of NSD2, Runx2, and BSP were measured by qPCR. The role of NSD2 in the osteogenic differentiation of BMSCs was further identified by silencing NSD2 via shRNA or overexpression of NSD2 via lentivirus transfection. The interactions of NSD2, H3K36me2 and Hoxa2 were identified via chromatin immunoprecipitation (ChIP). Luciferase reporting analysis was employed to confirm that NSD2 regulated the transcriptional activity of Hoxa2. Ovariectomized (OVX) was performed on mice to construct osteoporosis (OP) model. Subsequently, the bone mass was assessed by micro computed tomography (micro-CT) scan. ResultsDuring the osteogenesis of OP-derived hBMSCs, the levels of NSD2 and H3K36me2 significantly increased in 14 days of osteogenic induction. Inhibition of NSD2 via shRNA increased the RUNX2 and BSP expression of hBMSCs, while overexpression of NSD2 decreased RUNX2 and BSP expression of hBMSCs. ChIP analysis indicated NSD2-mediated H3K36me2 reduced the osteogenic differentiation of hBMSCs by regulating the osteogenic inhibitor Hoxa2. Accordingly, inhibition of NSD2 in vivo via tail vein injection of LV-shNSD2 lentivirus greatly alleviated OVX-induced osteoporosis in mice. ConclusionWe demonstrated that NSD2 inhibited the osteogenic differentiation in hBMSCs by transcriptionally downregulating Hoxa2 via H3K36me2 dimethylation. Inhibition of NSD2 effectively attenuated bone loss in murine osteoporosis and NSD2 is a promising target for clinical treatment of osteoporosis.

Macrophage-derived ectosomal miR-350-3p promotes osteoarthritis progression through downregulating chondrocyte H3K36 methyltransferase NSD1

Mechanical overloading can promote cartilage senescence and osteoarthritis (OA) development, but its impact on synovial macrophages and the interaction between macrophages and chondrocytes remain unknown. Here, we found that macrophages exhibited M1 polarization under mechanical overloading and secreted ectosomes that induced cartilage degradation and senescence. By performing miRNA sequencing on ectosomes, we identified highly expressed miR-350-3p as a key factor mediating the homeostatic imbalance of chondrocytes caused by M1-polarized macrophages, this result being confirmed by altering the miR-350-3p level in chondrocytes with mimics and inhibitor. In experimental OA mice, miR-350-3p was increased in synovium and cartilage, while intra-articular injection of antagomir-350-3p inhibited the increase of miR-350-3p and alleviated cartilage degeneration and senescence. Further studies showed that macrophage-derived ectosomal miR-350-3p promoted OA progression by inhibiting nuclear receptor binding SET domain protein 1(NSD1) in chondrocytes and regulating histone H3 lysine 36(H3K36) methylation. This study demonstrated that the targeting of macrophage-derived ectosomal miRNAs was a potential therapeutic method for mechanical overload-induced OA.

Identification of Novel NSD1 variations in four Pediatric cases with sotos Syndrome

ObjectiveSotos syndrome (SOTOS) is an uncommon genetic condition that manifests itself with the following distinctive features: prenatal overgrowth, facial abnormalities, and intellectual disability. This disorder is often associated with haploinsufficiency of the nuclear receptor-binding SET domain protein 1 (NSD1)gene. We investigated four pediatric cases characterized by early-onset overgrowth and developmental delay. The primary objective of this study was to achieve accurate genetic diagnoses.Design&MethodsA sequential analysis approach comprising chromosomal karyotyping, whole exome sequencing, and microarray analysis was conducted.ResultsAll four cases exhibited variations in the NSD1 gene, with the identification of four previously unreported de novo variants, each specific to one case.Specifically, Case 1 carried the NSD1 (NM_022455): c.2686 C > T(p.Q896X) variant, Case 2 had the NSD1 (NM_022455): c.2858_2859delCT(p.S953X) variant, Case 3 displayed a chromosomal aberration, chr5: 5q35.2q35.3(176,516,604–176,639,249)×1, which encompassed the 5′-untranslated region of NSD1, and Case 4 harbored the NSD1 (NM_022455): c.6397T > G(p.C2133G) variant.ConclusionThis study not only provided precise diagnoses for these cases but also supplied significant evidence to facilitate informed consultations. Furthermore, our findings expanded the spectrum of mutations associated with SOTOS.

Decreased NSD2 impairs stromal cell proliferation in human endometrium via reprogramming H3K36me2.

The proliferation of the endometrium is regulated by histone methylation. This study shows that decreased NSD2 impairs proliferative-phase endometrial stromal cell proliferation in patients with recurrent implantation failure via epigenetic reprogramming of H3K36me2 methylation on the promoter region of MCM7. Recurrent implantation failure (RIF) is a formidable challenge in assisted reproductive technology because of its unclear molecular mechanism. Impaired human endometrial stromal cell (HESC) proliferation disrupts the rhythm of the menstrual cycle, resulting in devastating disorders between the embryo and the endometrium. The molecular function of histone methylation enzymes in modulating HESC proliferation remains largely uncharacterized. Herein, we found that the levels of histone methyltransferase nuclear receptor binding SET domain protein 2 (NSD2) and the dimethylation of lysine 36 on histone H3 are decreased significantly in the proliferative-phase endometrium of patients with RIF. Knockdown of NSD2 in an HESC cell line markedly impaired cell proliferation and globally reduced H3K36me2 binding to chromatin, leading to altered expression of many genes. Transcriptomic analyses revealed that cell cycle-related gene sets were downregulated in the endometrium of patients with RIF and in NSD2‑knockdown HESCs. Furthermore, RNA-sequencing and CUT&Tag sequencing analysis suggested that NSD2 knockdown reduced the binding of H3K36me2 to the promoter region of cell cycle marker gene MCM7 (encoding minichromosome maintenance complex component 7) and downregulated its expression. The interaction of H3K36me2 with the MCM7 promoter was verified using chromatin immunoprecipitation-quantitative real-time PCR. Our results demonstrated a unifying epigenome-scale mechanism by which decreased NSD2 impairs endometrial stromal cell proliferation in the proliferative-phase endometrium of patients with RIF.

NSD3 in Cancer: Unraveling Methyltransferase-Dependent and Isoform-Specific Functions.

NSD3 (nuclear receptor-binding SET domain protein 3) is a member of the NSD histone methyltransferase family of proteins. In recent years, it has been identified as a potential oncogene in certain types of cancer. The NSD3 gene encodes three isoforms, the long version (NSD3L), a short version (NSD3S) and the WHISTLE isoforms. Importantly, the NSD3S isoform corresponds to the N-terminal region of the full-length protein, lacking the methyltransferase domain. The chromosomal location of NSD3 is frequently amplified across cancer types, such as breast, lung, and colon, among others. Recently, this amplification has been correlated to a chromothripsis event, that could explain the different NSD3 alterations found in cancer. The fusion proteins containing NSD3 have also been reported in leukemia (NSD3-NUP98), and in NUT (nuclear protein of the testis) midline carcinoma (NSD3-NUT). Its role as an oncogene has been described by modulating different cancer pathways through its methyltransferase activity, or the short isoform of the protein, through protein interactions. Specifically, in this review we will focus on the functions that have been characterized as methyltransferase dependent, and those that have been correlated with the expression of the NSD3S isoform. There is evidence that both the NSD3L and NSD3S isoforms are relevant for cancer progression, establishing NSD3 as a therapeutic target. However, further functional studies are needed to differentiate NSD3 oncogenic activity as dependent or independent of the catalytic domain of the protein, as well as the contribution of each isoform and its clinical significance in cancer progression.

Drug Discovery Targeting Nuclear Receptor Binding SET Domain Protein 2 (NSD2).

Nuclear receptor binding SET domain proteins (NSDs) catalyze the mono- or dimethylation of histone 3 lysine 36 (H3K36me1 and H3K36me2), using S-adenosyl-l-methionine (SAM) as a methyl donor. As a key member of the NSD family of proteins, NSD2 plays an important role in the pathogenesis and progression of various diseases such as cancers, inflammations, and infectious diseases, serving as a promising drug target. Developing potent and specific NSD2 inhibitors may provide potential novel therapeutics. Several NSD2 inhibitors and degraders have been discovered while remaining in the early stage of drug development. Excitingly, KTX-1001, a selective NSD2 inhibitor, has entered clinical trials. In this Perspective, the structures and functions of NSD2, its roles in various human diseases, and the recent advances in drug discovery strategies targeting NSD2 have been summarized. The challenges, opportunities, and future directions for developing NSD2 inhibitors and degraders are also discussed.

Chromatin regulation of transcriptional enhancers and cell fate by the Sotos syndrome gene NSD1

Nuclear receptor-binding SET-domain protein 1 (NSD1), a methyltransferase that catalyzes H3K36me2, is essential for mammalian development and is frequently dysregulated in diseases, including Sotos syndrome. Despite the impacts of H3K36me2 on H3K27me3 and DNA methylation, the direct role of NSD1 in transcriptional regulation remains largely unknown. Here, we show that NSD1 and H3K36me2 are enriched at cis-regulatory elements, particularly enhancers. NSD1 enhancer association is conferred by a tandem quadruple PHD (qPHD)-PWWP module, which recognizes p300-catalyzed H3K18ac. By combining acute NSD1 depletion with time-resolved epigenomic and nascent transcriptomic analyses, we demonstrate that NSD1 promotes enhancer-dependent gene transcription by facilitating RNA polymerase II (RNA Pol II) pause release. Notably, NSD1 can act as a transcriptional coactivator independent of its catalytic activity. Moreover, NSD1 enables the activation of developmental transcriptional programs associated with Sotos syndrome pathophysiology and controls embryonic stem cell (ESC) multilineage differentiation. Collectively, we have identified NSD1 as an enhancer-acting transcriptional coactivator that contributes to cell fate transition and Sotos syndrome development.

Analysis of Immunophenotypic Changes during Ex Vivo Human Erythropoiesis and Its Application in the Study of Normal and Defective Erythropoiesis.

Erythropoiesis is a highly regulated process and undergoes several genotypic and phenotypic changes during differentiation. The phenotypic changes can be evaluated using a combination of cell surface markers expressed at different cellular stages of erythropoiesis using FACS. However, limited studies are available on the in-depth phenotypic characterization of progenitors from human adult hematopoietic stem and progenitor cells (HSPCs) to red blood cells. Therefore, using a set of designed marker panels, in the current study we have kinetically characterized the hematopoietic, erythroid progenitors, and terminally differentiated erythroblasts ex vivo. Furthermore, the progenitor stages were explored for expression of CD117, CD31, CD41a, CD133, and CD45, along with known key markers CD36, CD71, CD105, and GPA. Additionally, we used these marker panels to study the stage-specific phenotypic changes regulated by the epigenetic regulator; Nuclear receptor binding SET Domain protein 1 (NSD1) during erythropoiesis and to study ineffective erythropoiesis in myelodysplastic syndrome (MDS) and pure red cell aplasia (PRCA) patients. Our immunophenotyping strategy can be used to sort and study erythroid-primed hematopoietic and erythroid precursors at specified time points and to study diseases resulting from erythroid dyspoiesis. Overall, the current study explores the in-depth kinetics of phenotypic changes occurring during human erythropoiesis and applies this strategy to study normal and defective erythropoiesis.

Evaluation of Cell Biology and Genetics using VIKOR Method

Cell biology and genetics are fields of heredity research. They enable experts to examine indigenous people's genetic data to identify their current state of health. By taking necessary precautions, one can protect their health using this technology. Cell biology has quickly expanded in the medical field and has emerged as the only treatment for issues with human reproduction. Genetics, or the science of genes and heredity, is all about the study of features that are passed down from one generation to the next. The subject of cell biology is the smallest units of life, cells, and their structures and functions. Understanding the structure and physiological functioning of single cells, and how cells interact and work together in great numbers to generate tissues and organisms, is a goal of cell biology. Cell biology is based on the notion that a cell is the basic unit of all life. Understanding the tissues and organisms that make up cells in great detail is made possible by concentrating on the cell. If you want to teach in a classroom, you can look into botany or zoology. If you're interested in biological or industrial sciences or medical research, you can choose from genetics, microbiology, or biotechnology. Cell biology encompasses both eukaryotic and prokaryotic cells and has a wide range of subtopics, including the research of cellular metabolism, cell communication, cell cycle, chemistry, and cell composition. Cells can be examined using a variety of microscopy techniques, cell culturing, and cell fractionation. There are two different cell types: prokaryotic and eukaryotic ones. Despite having differing morphologies (see Prokaryote, Eukaryote), eukaryotic organisms are remarkably comparable in terms of underlying molecular make-up and functions. Over the past 50 years, cell biology has seen remarkable expansion as a key area of basic science (1). Medicine makes use of information from basic science domains such as cell biology for the benefit of patients (2-4). A subfield of biology known as cell biology focuses on the cell, including its different types, structures, functions, and interactions with other cells. The subfields of cell biology include cell composition, cell cycle, cell communication, and cell metabolism. Research in several domains, including genetics, biochemistry, neuroscience, plant biology, molecular biology, microbiology, and immunology, is tied to those in cell biology. The VIKOR (VIšekriterijumsko Compromising Rangiranje) Optimal Replacement Select method is used in the evaluation of Epidermal Growth Factor Receptor, Fibroblast Growth Factor Receptors, Discoidin Domain Receptor, Mitogen-Activated Protein Kinase, and Nuclear Receptor-Binding SET Domain Protein alternatives for skin, lung, head/neck, and cervical cancer. Fibroblast Growth Factor Receptors have the highest rank, whereas Nuclear Receptor-Binding SET Domain Protein has the lowest rank.

Proteomic Analysis of Female Synovial Fluid to Identify Novel Biomarkers for Osteoarthritis.

Osteoarthritis (OA) is a highly prevalent degenerative joint condition that disproportionately affects females. The pathophysiology of the disease is not well understood, which makes diagnosis and treatment difficult. Given the physical connection of synovial fluid (SF) with articular tissues, the SF's composition can reflect relevant biological modifications, and has therefore been a focus of research. Previously, we demonstrated that extracellular vesicles isolated from the synovial fluid of OA patients carry different cargo (protein and miRNA) in a sex-specific manner. Given the increased prevalence and severity of OA in females, this study aims to identify differential protein content within the synovial fluid of female OA and non-osteoarthritic (non-OA) patients. We found that several proteins were differentially expressed in osteoarthritic females compared with age-matched controls. Presenilin, Coagulation Factor X, Lysine-Specific Demethylase 2B, Tenascin C, Leucine-Rich Repeat-Containing Protein 17 fragments, and T-Complex Protein 1 were negatively regulated in the OA group, with PGD Synthase, Tubulointerstitial Nephritis Antigen, and Nuclear Receptor Binding SET Domain Protein 1 positively regulated in the OA group. Database for Annotation, Visualization, and Integrated Discovery (DAVID) and QuickGO analyses established these proteins as significantly involved in many biological, cellular, and molecular processes. In conclusion, the protein content of female synovial fluid is altered in OA patients, which is likely to provide insights into gender-specific pathophysiology.

Tumor Promoting Role of NRIP1 in Oral Squamous Cell Carcinoma: The Involvement of NSD2-Mediated Histone Methylation of DGCR8.

Oral squamous cell carcinoma (OSCC) remains the most prevalent malignance in the head and neck with highly aggressive attributes. This study investigates the functions of nuclear receptor interacting protein 1 (NRIP1) and its target transcripts in the progression of OSCC. By analyzing four OSCC-related Gene Expression Omnibus (GEO) datasets (GSE9844, GSE23558, GSE25104 and GSE74530) and querying bioinformatics systems, we obtained NRIP1 as an aberrantly highly expressed transcription factor in OSCC. Increased NRIP1 was detected in OSCC cell lines. Artificial downregulation of NRIP1 significantly suppressed proliferation, migration and invasion, resistance to apoptosis, tumorigenicity, and in vivo metastatic potential of OSCC cells. Moreover, the bioinformatics analyses suggested nuclear receptor binding SET domain protein 2 (NSD2) as a target of NRIP1 and DGCR8 microprocessor complex subunit (DGCR8) as a target of NSD2. Indeed, we validated by chromatin immunoprecipitation and luciferase assays that NRIP1 activated the transcription of NSD2, and NSD2 increased DGCR8 transcription by modulating histone methylation near the DGCR8 promoter. Either NSD2 or DGCR8 upregulation in OSCC cells rescued their malignant properties. Collectively, this study demonstrates that NRIP1 augments malignant properties of OSCC cells by activating NSD2-mediated histone methylation of DGCR8.

Identification of alternative transcripts of NSD1 gene in Sotos Syndrome patients and healthy subjects

NSD1 gene (Nuclear Receptor Binding SET Domain Protein 1) encodes a methyltransferase that plays an important role in embryonic development. NSD1 is implicated in the transcription and methylation of histone H3 at lysine 36 (H3-K36), but the molecular mechanisms involved in these processes remain largely unknown. Pathogenic variants of NSD1 gene lead to Sotos syndrome, and have also been detected in some type of cancers, such as acute myeloid leukemia.In this study we have investigated NSD1 mRNA expression in fibroblast cell lines obtained from 14 Sotos patients and from 8 healthy controls. In addition to the expected NSD1 canonical transcript (isoform 1), we identified two additional, not yet reported, short NSD1 mRNA isoforms: NSD1 Δ5Δ7 (isoform 2) and NSD1 Δ19-23 (isoform 3), both in healthy subjects and in Sotos patients. We also show that NSD1 mutations in patients can be associated with a decreased level of NSD1 mRNA, as expected. Moreover, one patient, bearing the NSD1 variant c.6010-10G > A, expressed an additional shorter transcript derived from an aberrant splicing event.These results may provide a basis to elucidate the impact of different NSD1 pathogenic variants on the heterogeneity of phenotype associated with Sotos syndrome.

Discovery of a First-in-Class Degrader for Nuclear Receptor Binding SET Domain Protein 2 (NSD2) and Ikaros/Aiolos.

Overexpression of nuclear receptor binding SET domain protein 2 (NSD2) is frequent in multiple myeloma (MM). However, existing NSD2 inhibitors are largely ineffective in suppressing MM cell proliferation. Here, we report the discovery of a first-in-class NSD2 proteolysis targeting chimera (PROTAC) degrader, 9 (MS159), and two structurally similar controls, 17 (MS159N1) and 18 (MS159N2), with diminished binding to the cereblon (CRBN) E3 ligase and NSD2, respectively. Compound 9, but not 17 and 18, effectively degraded NSD2 in a concentration-, time-, CRBN-, and proteasome-dependent manner. Compound 9 also effectively degraded CRBN neo-substrates IKZF1 and IKZF3, but not GSPT1. Importantly, compound 9 was much more effective in suppressing the growth in cancer cells than the parent NSD2 binder. Moreover, compound 9 was bioavailable in mice. Altogether, compound 9 and its two controls 17 and 18 are valuable chemical tools for exploring the roles of NSD2 in health and disease.

H3K36me2 methyltransferase NSD2 orchestrates epigenetic reprogramming during spermatogenesis.

Spermatogenesis is precisely controlled by sophisticated gene expression programs and is driven by epigenetic reprogramming, including histone modification alterations and histone-to-protamine transition. Nuclear receptor binding SET domain protein 2 (Nsd2) is the predominant histone methyltransferase catalyzing H3K36me2 and its role in male germ cell development remains elusive. Here, we report that NSD2 protein is abundant in spermatogenic cells. Conditional loss of Nsd2 in postnatal germ cells impaired fertility owing to apoptosis of spermatocytes and aberrant spermiogenesis. Nsd2 deficiency results in dysregulation of thousands of genes and remarkable reduction of both H3K36me2 and H3K36me3 in spermatogenic cells, with H3K36me2 occupancy correlating positively with expression of germline genes. Nsd2 deficiency leads to H4K16ac elevation in spermatogenic cells, probably through interaction between NSD2 and PSMA8, which regulates acetylated histone degradation. We further reveal that Nsd2 deficiency impairs EP300-induced H4K5/8ac, recognized by BRDT to mediate the eviction of histones. Accordingly, histones are largely retained in Nsd2-deficient spermatozoa. In addition, Nsd2 deficiency enhances expression of protamine genes, leading to increased protamine proteins in Nsd2-deficient spermatozoa. Our findings thus reveal a previously unappreciated role of the Nsd2-dependent chromatin remodeling during spermatogenesis and provide clues to the molecular mechanisms in epigenetic abnormalities impacting male reproductive health.

Abstract 769: Genomic and transcriptomic characterization of benign and malignant struma ovarii

Abstract Background: Struma Ovarii (SO) is a rare ovarian teratoma characterized by the presence of thyroid tissue in >50% of the tumor. The majority of SO are benign; however, malignant transformation occurs in up to 5% of the cases. The molecular foundations of benign and malignant SO are grossly unknown. Therefore, the goal of this study was to perform the first comprehensive genomic and transcriptomic analysis of the benign and malignant SO. Material and Method: We performed whole-exome sequencing (WES) and targeted RNA-sequencing (seq) on the DNA and RNA extracted from formalin-fixed paraffin-embedded SO tumor tissue samples. WES library was prepared using Agilent’s SureSelect XT HS2 kit, with 4 samples failing the quality assessment (QA). Variants were called from GATK processed WES data and annotated using VEP (with ClinVar and COSMIC databases). The targeted RNA-Seq library was prepared using the TruSight RNA Pan-Cancer Panel kit covering 1385 cancer genes, with all samples passing QA. The clinical characteristics of the study cohort were summarized by percentages for categorical variables and medians with 25-75% interquartile ranges for continuous variables. Results: The study included 31 tissue samples - 21 benign and 10 malignant, including 6 cases of papillary thyroid cancer (PTC), 3 of follicular variant of PTC, and 1 of follicular thyroid cancer. Patients with benign SO were characterized by the median age at diagnosis of 39 years [33-54], tumor size of 3.1 cm [2.5-5.8], while the patients with malignant SO presented at age of 45 [28-54], tumor size of 6 cm [0.85-14] and metastatic disease in 30% (3/10) - 2 patients with peritoneal metastases and 1 patient with pelvic lymph node metastases. The E1A Binding Protein P300, EP300 (6/27), and Isocitrate dehydrogenase, IDH2 (5/27) were the topmost mutated genes in the SO samples. Malignant SO samples were characterized with the presence of pathogenic variants of KRAS (pQ61L and pG12V), NRAS (pQ61R), TP53 (splice site) mutations, and Nuclear Receptor Binding SET Domain Protein 1 (NSD1) fusion as the most common molecular drivers. Among benign SO samples, the most common driver was Thyroglobulin (TG) fusion with either Guanine Nucleotide binding protein (GNAS) or Rac Family Small GTPase 1 (RAC1). Differential expression analysis showed that the member of tumor suppressor family - tumor protein 63 (TP63) was the most downregulated (Log2FC = -3), while Double-sex and Mab-3 Related Transcription Factor 1 (DMRT1), implicated in the development of germ cell tumors, was the most upregulated gene in malignant SO samples over benign (Log2FC = 2.1; padj<0.05). Conclusions: In contrast to cancer arising from the thyroid gland, characterized by BRAFV600E as the most common mutation, malignant SO belongs to RAS-like tumors. The downregulation of tumor suppressors and upregulation of DMRT1 might be implicated in the malignant transformation of SO. Citation Format: Shilpa Thakur, Darryl Nousome, Kshama Aswath, Stephanie Cardenas, Sonam Kumari, Ruth Adewale, Maria Merino, Esra Dikoglu, Padmasree Veeraraghavan, Sriram Gubbi, Joanna Klubo-Gwiezdzinska. Genomic and transcriptomic characterization of benign and malignant struma ovarii [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 769.

Discovery of a potent and selective proteolysis targeting chimera (PROTAC) degrader of NSD3 histone methyltransferase

Nuclear receptor binding SET domain protein 3 (NSD3) is an attractive potential target in the therapy for human cancers. Herein, we report the discovery of a series of small-molecule NSD3 degraders based on the proteolysis targeting chimera (PROTAC) strategy. The represented compound 8 induces NSD3 degradation with DC50 values of 1.43 and 0.94 μM in NCI–H1703 and A549 lung cancer cells, respectively, and shows selectivity over two other NSD proteins. 8 reduces histone H3 lysine 36 methylation and induces apoptosis and cell cycle arrest in lung cancer cells. Moreover, the RNA sequencing and immunohistochemistry assays showed that 8 downregulates NSD3-associated gene expression. Significantly, 8, but not 1 (a reported NSD3-PWWP antagonist) could inhibit the cell growth of NCI–H1703 and A549 cells. A single administration of 8 effectively decreases the NSD3 protein level in lung cancer xenograft models. Therefore, this study demonstrated that inducing NSD3 degradation is a more effective approach inhibiting the function of NSD3 than blocking the NSD3-PWWP domain, which may provide a potential therapeutic approach for lung cancer.

METTL3 enhances NSD2 mRNA stability to reduce renal impairment and interstitial fibrosis in mice with diabetic nephropathy

BackgroundNuclear receptor-binding SET domain protein 2 (NSD2) is a histone methyltransferase that has been demonstrated to regulate insulin secretion and glucose concentration. This study focused on the role of NSD2 in the renal impairment during diabetic nephropathy (DN).MethodsSerum NSD2 level in patients with DN was examined, and its correlations with the renal impairment-related indicators were examined. A murine model of DN was established, and mouse mesangial cells (SV40-MES-13) were treated with high-glucose (HG) to mimic a DN-like condition in vitro. Overexpression of NSD2 was introduced into mice or cells for in vivo and in vitro studies. The m6A level in HG-treated SV40-MES-13 cells was analyzed. METTL3 expression and its correlation with NSD2 were determined.ResultsNSD2 was poorly expressed in the serum of patients with DN and was negatively correlated with the levels of fasting blood sugar (FBG), serum creatinine (SCr), serum cystatin C (S-Cys-C), the 24-h urine protein (24-h U-protein) and the urine cystatin C (U-Cys-C). NSD2 overexpression reduced the kidney weight and reduced renal impairment in mice. It also suppressed interstitial fibrosis in mouse kidney tissues and reduced fibrosis-related markers in HG-treated SV40-MES-13 cells. HG treatment reduced the m6A level in the cells. METTL3 promoted m6A modification of NDS2 mRNA and enhanced its stability by YTHDF1. METTL3 overexpression alleviated renal impairment and fibrosis in vivo and in vitro. But the protective role was blocked upon NSD2 silencing.ConclusionThis study demonstrates that METTL3 promotes NSD2 mRNA stability by YTHDF1 to alleviate progression of DN.

NSD2 activates the E2F transcription factor 1/Y-box binding protein 2 axis to promote the malignant development of oral squamous cell carcinoma

ObjectiveNuclear receptor-binding SET domain protein 2 (NSD2) belongs to the SET histone methyltransferase family with potential oncogenic roles. This study aimed to probe the roles of NSD2 and its relevant molecules in oral squamous cell carcinoma (OSCC). MethodsAn OSCC-related GSE138206 dataset was analyzed to identify potential key genes implicated in OSCC development. NSD2 expression in OSCC tissues and cells was examined. NSD2 silencing was administrated in OSCC cells to examine its function in cell growth in vitro and in vivo. Downstream molecules mediated by NSD2 were predicted using bioinformatic tools. Rescue experiments of E2F transcription factor 1 (E2F1) and Y-box binding protein 2 (YBX2) were performed to validate their participation in NSD2-regulated events. ResultsNSD2 was highly expressed in OSCC tissues and cells, along with elevated expression of H3K36me2, a major target of NSD2-mediated methylation. NSD2 silencing significantly reduced proliferation, invasion and epithelial to mesenchymal transition of OSCC cells but induced cell apoptosis, and it reduced growth of xenograft tumors in nude mice. Downregulation of NSD2 led to transcriptional suppression of E2F1 by inhibiting H3K36me2 modification at the E2F1 promoter, while E2F1 transcriptionally activated YBX2. Either upregulation of E2F1 or YBX2 restored the malignant behaviors of OSCC cells suppressed by NSD2 silencing. ConclusionThis work demonstrates that NSD2 plays an oncogenic role in OSCC by activating E2F1 and YBX2. Silencing of NSD2, E2F1 or YBX2 may help suppress the progression of OSCC.

Melatonin enhances osteoblastogenesis of senescent bone marrow stromal cells through NSD2-mediated chromatin remodelling.

BackgroundAging‐associated osteoporosis is frequently seen in the elderly in clinic, but efficient managements are limited because of unclear nosogenesis. The current study aims to investigate the role of melatonin on senescent bone marrow stromal cells (BMSCs) and the underlying regulating mechanism.MethodsMelatonin levels were tested by ELISA. Gene expression profiles were performed by RNA‐sequencing, enrichment of H3K36me2 on gene promoters was analyzed by Chromatin Immunoprecipitation Sequencing (ChIP‐seq), and chromatin accessibility was determined by Assay for Transposase‐Accessible Chromatin with high‐throughput sequencing (ATAC‐seq). Osteogenesis of BMSCs in vitro was measured by Alizarin Red and Alkaline Phosphatase staining, and in vivo effects of melatonin was assessed by histological staining and micro computed tomography (micro‐CT) scan. Correlation of NSD2 expression and severity of senile osteoporosis patients were analyzed by Pearson correlation.ResultsMelatonin levels were decreased during aging in human bone marrow, accompanied by downregulation of the histone methyltransferase nuclear receptor binding SET domain protein 2 (NSD2) expression in the senescent BMSCs. Melatonin stimulated the expression of NSD2 through MT1/2‐mediated signaling pathways, resulting in the rebalancing of H3K36me2 and H3K27me3 modifications to increase chromatin accessibility of the osteogenic genes, runt‐related transcription factor 2 (RUNX2) and bone gamma‐carboxyglutamate protein (BGLAP). Melatonin promoted osteogenesis of BMSCs in vitro, and alleviates osteoporosis progression in the aging mice. In clinic, severity of senile osteoporosis (SOP) was negatively correlated with melatonin level in bone marrow, as well as NSD2 expression in BMSCs. Similarly, melatonin remarkably enhanced osteogenic differentiation of BMSCs derived from SOP patients in vitro.ConclusionsCollectively, our study dissects previously unreported mechanistic insights into the epigenetic regulating machinery of melatonin in meliorating osteogenic differentiation of senescent BMSC, and provides evidence for application of melatonin in preventing aging‐associated bone loss.

Nuclear receptor binding SET domain protein 1 promotes epithelial-mesenchymal transition in paclitaxel-resistant breast cancer cells via regulating nuclear factor kappa B and F-box and leucine-rich repeat protein 11

ABSTRACT Breast cancer (BC) is regarded as the major cause of cancer-associated deaths in women. Paclitaxel exerts a critical impact on the chemotherapy of BC, but the resistance to paclitaxel becomes a great obstacle in treating the disease. It is reported that noncoding RNA nuclear receptor binding SET domain protein 1 (NSD1) plays a significant role in drug resistance; however, the special role of NSD1 in paclitaxel-resistant BC is unclear. Human BC cell line MCF-7 was used to establish paclitaxel-resistant BC cells (MCF-7/PR). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) displayed that NSD1 and F-box and leucine-rich repeat protein 11 (FBXL11) were highly expressed in BC tissues. Western blotting was utilized for protein level assessment. Cell counting kit-8 (CCK-8), Transwell, wound healing assays, and animal experiments were conducted to examine the influence of NSD1 or FBXL11 on the malignant behaviors of BC in vitro and in vivo, respectively. Transfected MCF-7/PR cells were injected subcutaneously into BALB/c nude mice with or without treatment of paclitaxel. The nuclear factor kappa B (NF-kB) activity was evaluated by the luciferase reporter assay. Results showed that NSD1 knockdown inhibited the epithelial-mesenchymal transition (EMT), migration and invasiveness of BC in vitro, which was rescued by FBXL11 overexpression. Furthermore, NSD1 silencing promoted paclitaxel sensitivity of paclitaxel-resistant BC cells and suppressed tumor growth and paclitaxel resistance in vivo. NSD1 knockdown reduced NF-kB activity, while FBXL11 inhibition markedly increased NF-kB activity. Collectively, NSD1 facilitates the EMT, migration and invasion in paclitaxel-resistant BC cells via regulating NF-kB and FBXL11.