Jumonji Domain-containing Protein 3 Research Articles

H2S Donor SPRC Ameliorates Cardiac Aging by Suppression of JMJD3, a Histone Demethylase.

Aims: S-propargyl-cysteine (SPRC) is an endogenous hydrogen sulfide (H2S) donor obtained by modifying the structure of S-allyl cysteine in garlic. This study aims to investigate the effect of SPRC on mitigating cardiac aging and the involvement of jumonji domain-containing protein 3 (JMJD3), a histone demethylase, which represents the primary risk factor in major aging related diseases, in this process, elucidating the preliminary mechanism through which SPRC regulation of JMJD3 occurs. Results: In vitro, SPRC mitigated the elevated levels of reactive oxygen species, senescence-associated β-galactosidase, p53, and p21, reversing the decline in mitochondrial membrane potential, which represented a reduction in cellular senescence. In vivo, SPRC improved Dox-induced cardiac pathological structure and function. Overexpression of JMJD3 accelerated cardiomyocytes and cardiac senescence, whereas its knockdown in vitro reduced the senescence phenotype. The potential binding site of the upstream transcription factor of JMJD3, sheared X box binding protein 1 (XBP1s), was determined using online software. SPRC promoted the expression of cystathionine γ-lyase (CSE), which subsequently inhibited the IRE1α/XBP1s signaling pathway and decreased JMJD3 expression. Innovations: This study is the first to establish JMJD3 as a crucial regulator of cardiac aging. SPRC can alleviate cardiac aging by upregulating CSE and inhibiting endoplasmic reticulum stress pathways, which in turn suppress JMJD3 expression. Conclusions: JMJD3 plays an essential role in cardiac aging regulation, whereas SPRC can suppress the expression of JMJD3 by upregulating CSE, thus delaying cardiac aging, which suggests that SPRC may serve as an aging protective agent, and pharmacological targeting of JMJD3 may also be a promising therapeutic approach in age-related heart diseases.

Histone demethylase JMJD3 inhibits alveolar bone loss by regulating macrophage polarization in periodontitis

Objective: To investigate the expression of histone demethylase, Jumonji domain-containing protein 3 (JMJD3), in inflammatory periodontal tissues and its potential mechanism for the regulation of periodontitis. Methods: The results of single-cell sequencing of periodontal tissues published in the Gene Expression Omnibus (GEO) database in 2022 were analyzed. Nine gingival samples each from healthy and inflamed periodontal patients were collected during periodontal surgery or tooth extractions for immunohistochemical staining and real-time fluorescence quantitative PCR (RT-qPCR). Mice periodontitis models were constructed, and the experimental groups were: healthy control+saline group, silk ligation+saline group, silk ligation+GSK-J4(inhibitor of JMJD3) group. Lipopolysaccharide (LPS) derived from Porphyromonas gingivalis (Pg) (Pg-LPS) was used to mimic the periodontal inflammatory microenvironment. The macrophages were treated with small interfering RNA (siRNA) targeting Jmjd3 and the JMJD3 inhibitor GSK-J4. siRNA transfection experiments were grouped into the following: the NC group (negative control sequence transfection group), the siRNA-Jmjd3 group, the NC+LPS group, siRNA-Jmjd3+LPS group. Inhibitor experiments were grouped as dimethyl sulfoxide (DMSO) group, GSK-J4 group, DMSO+LPS group, GSK-J4+LPS group. Western blotting and immunofluorescence staining were used to explore the effects of JMJD3 on macrophage polarization and periodontal inflammation in the in vivo and in vitro settings. Results: RT-qPCR results showed that JMJD3 expression in gingival tissues of periodontitis patients (1.97±0.91) was significantly higher than that in healthy gingival tissues (1.00±0.33) (t=2.45, P=0.048). RT-qPCR results of in vitro experiments showed that either siRNA knockdown of JMJD3 or inhibition of JMJD3 using GSK-J4 promoted M1 polarization and inhibited M2 polarization in macrophages under inflammatory environment: the expression of arginase I (Arg 1) in the NC+LPS group (0.90±0.06) was significantly higher than that in the siRNA-Jmjd3+LPS group (0.61±0.11) (P<0.01); the expression of interleukin (Il)-6, Il-1β, and tumor necrosis factor alpha (Tnf-α) in the NC+LPS group (8.50±0.16, 5.56±0.20, 3.44±0.16) were significantly lower than those in the siRNA-Jmjd3+LPS group (14.63±0.48, 8.55±0.10, 11.72±0.16) (P<0.01). The expression of Arg-1, Ym1, Il-10 in the DMSO+LPS group (0.82±0.01, 0.35±0.16, 1.47±0.11) were significantly higher (P<0.01) than the GSK-J4+LPS group (0.55±0.03, 0.22±0.21, 0.51±0.11); the expression of Il-6, Il-1β, and Tnf-α in the DMSO+LPS group (2.03±0.13, 3.63±0.14, 4.06±0.03) were significantly lower than the GSK-J4+LPS group (2.69±0.16, 15.04±1.15, 4.36±0.10) (P<0.01). The results of the in vivo experiments revealed that inhibition of JMJD3 exacerbated bone loss in experimental periodontitis mice, increased macrophage M1 polarization, and decreased M2 polarization in inflamed periodontal tissues. The buccal cemento-enamel junction (CEJ)-alveolar bone crest (ABC), palatal CEJ-ABC, as well as the ratio of M1/M2 type macrophages were significantly lower in the silk ligation+saline group [(0.26±0.03), (0.24±0.01) mm, 0.35±0.10) than in the silk ligation+GSK-J4 group [(0.34±0.04), (0.30±0.05) mm, 2.50±0.58) (t=3.65, P=0.006; t=2.67, P=0.049; t=7.31, P=0.004; respectively). Conclusions: Single-cell sequencing as well as the in vitro and in vivo experiments verified that JMJD3 expression was upregulated in periodontitis periodontal tissues. JMJD3 may exert a protective role in periodontitis by regulating macrophage polarization, thereby inhibiting alveolar bone destruction associated with the periodontitis.

Emodin suppresses mast cell migration via modulating the JAK2/STAT3/JMJD3/CXCR3 signaling to prevent cystitis.

This study aimed to determine the preventive effects of emodin on cyclophosphamide (CYP)-induced cystitis and to explore the molecular mechanism. In vivo, mice were modeled by CYP. Before a half hour of CYP treatment, Jumonji domain-containing protein-3 (JMJD3)inhibitors (GSK-J4) and emodin were used to treat CYP model mice. Bladder samples were stained for hematoxylin-eosin and toluidine blue. Next, JMJD3 was quantified by immunofluorescence staining, RT-PCR, and Western blot. CXCR3 was quantified by Western blot and ELISA. In vitro, before stimulated by lipopolysaccharide (LPS), human bladder smooth muscle cells (hBSMCs) were transfected with pcDNA3.1-JMJD3 plasmids, shRNA-JMJD3 plasmids or pretreated with emodin. Collected cells to detect JMJD3 and CXCR3 ligands again; collected supernatant of culture for Transwell assay. Finally, as the JAK2 inhibitor, AG490 was used to pretreat LPS-induced hBSMCs. Western blot was performed to quantify proteins. Emodin inhibited mast cell migration and suppressed the expression of JMJD3, CXCR3, and CXCR3 ligands, not only in vivo but also in vitro. The pharmacological effects of emodin were similar to GSK-J4 or JMJD3 inhibition. In addition, emodin significantly downregulated the phosphorylation of JAK2 and STAT3, and inhibited JMJD3/CXCR3 axis transduction like AG490. Emodin has a preventive effect on cystitis by inhibiting mast cell migration through inhibition of the JAK2/STAT3/JMJD3/CXCR3 signaling pathway.

Lycopene promoted M2 macrophage polarization via inhibition of NOTCH1-PI3K-mTOR-NF-κB-JMJD3-IRF4 pathway in response to Escherichia coli infection in J744A.1 cells.

Escherichia coli (E. coli) can induce severe clinical bovine mastitis, which is to blame for large losses experienced by dairy farms. Macrophage polarization into various states is in response to pathogen infections. Lycopene, a naturally occurring hydrocarbon carotenoid, relieved inflammation by controlling M1/M2 status of macrophages. Thus, we wanted to explore the effect of lycopene on polarization states of macrophages in E. coli-induced mastitis. Macrophages were cultivated with lycopene for 24, before E. coli inoculation for 6h. Lycopene (0.5μmol/L) significantly enhanced cell viabilities and significantly reduced lactic dehydrogenase (LDH) levels in macrophages, whereas 2 and 3μmol/L lycopene significantly enhanced LDH activities. Lycopene treatment significantly reduced the increase in LDH release, iNOS, CD86, TNF-α, IL-1β and phosphatase and tensin homolog (PTEN) expressions in E. coli group. 0.5μmol/L lycopene significantly increased E. coli-induced downregulation of CD206, arginase I (ARG1), indoleamine 2,3-dioxygenase (IDO), chitinase 3-like 3 (YM1), PI3K, AKT, p-AKT, mammalian target of rapamycin (mTOR), p-mTOR, jumonji domain-containing protein-3 (JMJD3) and interferon regulatory factor 4 (IRF4) levels. Moreover, Ginkgolic acid C17:1 (a specific PTEN inhibitor), 740YPDGFR (a specific PI3K activator), SC79 (a specific AKT activator) or CHPG sodium salt (a specific NF-κB activator) significantly decreased CD206, AGR1, IDO and YM1 expressions in lycopene and E. coli-treated macrophages. Therefore, lycopene increased M2 macrophages via inhibiting NOTCH1-PI3K-mTOR-NF-κB-JMJD3-IRF4 pathway in response to E. coli infection in macrophages. These results contribute to revealing the pathogenesis of E. coli-caused bovine mastitis, providing the new angle of the prevention and management of mastitis.

Knockdown of JMJD3 ameliorates cigarette smoke extract-triggered bronchial epithelial cell injury via ACSL4-dependent ferroptosis

Chronic obstructive pulmonary disease (COPD), a heterogeneity of chronic respiratory disease pattern, presents considerable prevalence and mortality. We aimed to explore the role and mechanisms of Jumonji domain-containing protein-3 (JMJD3) in COPD. The viability and JMJD3 expression in human bronchial epithelial cell line BEAS-2B were respectively assayed by CCK-8 assay and Western blot following stepwise exposure to increasing concentrations of cigarette smoke extract (CSE). After JMJD3 was silenced and acyl-CoA synthetase long-chain family member 4 (ACSL4) was overexpressed in CSE-treated BEAS-2B cells, cell viability, cytotoxicity, oxidative stress and total iron level were estimated using kits. ELISA estimated inflammatory levels. DCFH-DA probe and BODIPY 581/591 C11 probe were exposed to assess ROS production and lipid peroxidation. Western blot tested the expressions of ferroptosis-associated proteins. Besides, H3K27me3 and ACSL4 expressions were tested by Western blot and immunofluorescence staining. In CSE-induced BEAS-2B cells, JMJD3 expression was increased and deletion of JMJD3 improved cell viability, reduced LDH release, mitigated inflammation, oxidative stress and inhibited ferroptosis. Moreover, JMJD3 interference raised H3K27me3 expression whereas lessened ACSL4 expression in CSE-treated BEAS-2B cells. CSE exposure reduced the abundance of ACSL4 in H3K27me3 antibody. Further ACSL4 elevation reversed the impacts of JMJD3 silencing on the damage of CSE-induced BEAS-2B cells. Collectively, JMJD3 depletion might suppress ferroptosis mediated by ACSL4 to alleviate CSE-triggered inflammation and oxidative stress in BEAS-2B cells.

Targeting Esophageal Squamous Cell Carcinoma by Combining Copper Ionophore Disulfiram and JMJD3/UTX Inhibitor GSK J4.

The alcohol-averse drug disulfiram has been reported to have anti-tumor effects and is well suited for drug combinations. In order to identify potential drug combinations in esophageal squamous cell carcinoma (ESCC), we screened a bioactive compound library with the disulfiram copper chelation product CuET. The Jumonji domain-containing protein 3 (JMJD3) and the ubiquitously transcribed tetratricopeptide repeat protein X-linked (UTX) inhibitor GSK J4 were identified. To further understand the molecular mechanism underlying the efficient drug combination, we applied quantitative mass spectrometry to analyze the signaling pathway perturbation after drug treatment. The data revealed that the synergistic effect of GSK J4 and CuET was due to the interaction among JMJD3 and UTX, which may play important roles in maintaining endoplasmic reticulum (ER) homeostasis in tumor cells. Interestingly, our clinical data analysis showed that high expression of JMJD3 and UTX was associated with T stage and worse prognosis of ESCC patients, further supporting the importance of the above findings. In conclusion, our findings suggest that the combination of CuET and targeting JMJD3/UTX may be a safe, effective, and available treatment for ESCC.

MEK/ERK and PI3K/AKT pathway inhibitors affect the transformation of myelodysplastic syndrome into acute myeloid leukemia via H3K27me3 methylases and de‑methylases.

The transformation of myelodysplastic syndrome (MDS) into acute myeloid leukemia (AML) poses a significant clinical challenge. The trimethylation of H3 on lysine 27 (H3K27me3) methylase and de‑methylase pathway is involved in the regulation of MDS progression. The present study investigated the functional mechanisms of the MEK/ERK and PI3K/AKT pathways in the MDS‑to‑AML transformation. MDS‑AML mouse and SKM‑1 cell models were first established and this was followed by treatment with the MEK/ERK pathway inhibitor, U0126, the PI3K/AKT pathway inhibitor, Ly294002, or their combination. H3K27me3 methylase, enhancer of zeste homolog (EZH)1, EZH2, demethylase Jumonji domain‑containing protein‑3 (JMJD3) and ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) and H3K27me3 protein levels were determined using western blot analysis. Cell viability, cycle distribution and proliferation were assessed using CCK‑8, flow cytometry, EdU and colony formation assays. The ERK and AKT phosphorylation levels in clinical samples and established models were determined, and SKM‑1 cell behaviors were assessed. The levels of H3K27me3 methylases and de‑methylases and distal‑less homeobox 5 (DLX5) were measured. The results revealed that the ERK and AKT phosphorylation levels were elevated in patients with MDS and MDS‑AML, and in mouse models. Treatment with U0126, a MEK/ERK pathway inhibitor, and Ly294002, a PI3K/AKT pathway inhibitor, effectively suppressed ERK and AKT phosphorylation in mice with MDS‑AML. It was observed that mice with MDS treated with U0126/Ly294002 exhibited reduced transformation to AML, delayed disease transformation and increased survival rates. Treatment of the SKM‑1 cells with U0126/Ly294002 led to a decrease in cell viability and proliferation, and to an increase in cell cycle arrest by suppressing ERK/PI3K phosphorylation. Moreover, treatment with U0126/Ly294002 downregulated EZH2/EZH1 expression, and upregulated JMJD3/UTX expression. The effects of U0126/Ly294002 were nullified when EZH2/EZH1 was overexpressed or when JMJD3/UTX was inhibited in the SKM‑1 cells. Treatment with U0126/Ly294002 also resulted in a decreased H3K27me3 protein level and H3K27me3 level in the DLX5 promoter region, leading to an increased DLX5 expression. Overall, the findings of the present study suggest that U0126/Ly294002 participates in MDS‑AML transformation by modulating the levels of H3K27me3 methylases and de‑methylases, and regulating DLX5 transcription and expression.

Icariin promotes osteogenic differentiation through the mmu_circ_0000349/mmu-miR-138-5p/Jumonji domain-containing protein-3 axis

Circular RNAs (circRNAs) regulate Jumonji domain-containing protein-3 (JMJD3) by sponging with microRNAs (miRNAs). This study aimed to investigate the role of icariin on specific circRNA/miRNA/JMJD3 axis in osteogenic differentiation of MC3T3-E1 cells. CircRNA sequencing was performed on the MC3T3-E1 cells induced by osteogenic differentiation medium for 1 d (negative control (NC) group) and 14 d (osteogenesis group). And mmu_circ_0000349 was verified using Sanger sequencing, ribonuclease R degradation, and actinomycin D assay. The function of mmu_circ_0000349 was validated by detecting the expressions of osteogenic differentiation markers, alkaline phosphatase (ALP), and runt-related transcription (RUNX2), via real-time quantitative PCR (qPCR) and Western blotting or ALP and alizarin red staining assay. Dual luciferase reporter gene assay confirmed the relationship between mmu_circ_0000349 and mmu-miR-138-5p (or mmu-miR-138-5p and JMJD3). Meanwhile, the JMJD3 binding to mmu_circ_0000349 was screened using an RNA pull-down assay. qPCR and Western blotting confirmed the effect of icariin on the mmu_circ_0000349/mmu-miR-138-5p/JMJD3 axis and osteogenic differentiation. As MC3T3-E1 osteogenic differentiation progressed, the JMJD3 expression level increased. A total of 361 circRNAs exhibited differences between the NC and osteogenesis groups. After validation, mmu_circ_0000349 was further analyzed as it exhibited the largest expression. And mmu_circ_0000349 was identified as a stable circular structure. Overexpression of mmu_circ_0000349 increased the expression levels of ALP and RUNX2, enhanced ALP activity, and increased the number of mineralized nodules; contrarily, inhibition of mmu_circ_0000349 exerted opposite effects. The data also confirmed that mmu_circ_0000349 regulated JMJD3 by sponging with mmu-miR-138-5p. With the increase in icariin concentration and time for treatment, the expression levels of mmu_circ_0000349, JMJD3, ALP, and RUNX2 also increased, whereas that of mmu-miR-138-5p decreased. In conclusion, Icariin promoted osteogenic differentiation by regulating the mmu_circ_0000349/mmu-miR-138-5p/JMJD3 pathway. Therefore, this provides a theoretical basis for the treatment of diseases related to osteogenic differentiation.

Macrophage LMO7 deficiency facilitates inflammatory injury via metabolic-epigenetic reprogramming

Inflammatory bowel disease (IBD) is a formidable disease due to its complex pathogenesis. Macrophages, as a major immune cell population in IBD, are crucial for gut homeostasis. However, it is still unveiled how macrophages modulate IBD. Here, we found that LIM domain only 7 (LMO7) was downregulated in pro-inflammatory macrophages, and that LMO7 directly degraded 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) through K48-mediated ubiquitination in macrophages. As an enzyme that regulates glycolysis, PFKFB3 degradation led to the glycolytic process inhibition in macrophages, which in turn inhibited macrophage activation and ultimately attenuated murine colitis. Moreover, we demonstrated that PFKFB3 was required for histone demethylase Jumonji domain-containing protein 3 (JMJD3) expression, thereby inhibiting the protein level of trimethylation of histone H3 on lysine 27 (H3K27me3). Overall, our results indicated the LMO7/PFKFB3/JMJD3 axis is essential for modulating macrophage function and IBD pathogenesis. Targeting LMO7 or macrophage metabolism could potentially be an effective strategy for treating inflammatory diseases.

13-Cis Retinoic Acid Induces Neuronal Differentiation in Daoy (Medulloblastoma) Cells Through Epigenetic Regulation of Topoisomerase IIβ.

Medulloblastoma (MB) is a malignant tumor of the cerebellum that occurs in children and infants. Abnormal neuronal differentiation can lead to brain tumors, and topoisomerase IIβ (Top IIβ) plays an important role in neuronal differentiation. The aim of this study was to investigate the molecular mechanism of 13-cis retinoic acid (13-cis RA) promoting the expression of Top IIβ and inducing neuronal differentiation in human MB Daoy cells. The results showed that 13-cis RA inhibited the cell proliferation and induced cell cycle arrest in G0/G1 phase. The cells differentiated into a neuronal phenotype, with high expression of the neuronal marker microtubule-associated protein 2 (MAP2) and abundant Top IIβ, and obvious neurite growth. Chromatin immunoprecipitation (ChIP) assay showed that histone H3 lysine 27 tri-methylation (H3K27me3) modification in Top IIβ promoter decreased after 13-cis RA-induced cell differentiation, while jumonji domain-containing protein 3 (JMJD3) binding in Top IIβ promoter increased. These results suggest that H3K27me3 and JMJD3 can regulate the expression of Top IIβ gene, which is related to inducing neural differentiation. Our results provide new insights into understanding the regulatory mechanisms of Top IIβ during neuronal differentiation and imply the potential application of 13-cis RA in the clinical treatment of MB.

JMJD3 Is Required for Acute Pancreatitis and Pancreatitis-Associated Lung Injury.

Acute pancreatitis (AP) can be complicated by inflammatory disorders of remote organs, such as lung injury, in which Jumonji domain-containing protein 3 (JMJD3) plays a vital role in proinflammatory responses. Currently, we found that JMJD3 expression was upregulated in the pancreas and lung in an AP male mouse model, which was also confirmed in AP patients. Further experiments revealed that the upregulation of JMJD3 and proinflammatory effects were possibly exerted by mitochondrial DNA (mtDNA) or oxidized-mtDNA from tissue injury caused by AP. The release of mtDNA and oxidized-mtDNA contributed to the infiltration of inflammatory monocytes in lung injury through the stimulator of IFN genes (STING)/TLR9-NF-κB-JMJD3-TNF-α pathway. The inhibition of JMJD3 or utilization of Jmjd3-cKO mice significantly alleviated pulmonary inflammation induced by AP. Blocking mtDNA oxidation or knocking down the TLR9/STING pathway effectively alleviated inflammation. Therefore, inhibition of JMJD3 or STING/TLR9 pathway blockage might be a potential therapeutic strategy to treat AP and the associated lung injury.

Deficiency of p53 Causes the Inadequate Expression of miR-1246 in B Cells of Systemic Lupus Erythematosus.

Underexpression of p53 is considered the leading cause of the decreased miR-1246 expression in B cells of systemic lupus erythematosus (SLE) patients, yet the exact mechanism of action still remains unclear. To further explore the molecular mechanism of p53 upregulating miR-1246 expression, we targeted the methylation and acetylation of histone H3 in the miR-1246 promoter region of SLE B cells. We found that increased histone H3 trimethylation at Lys27 (H3K27me3) and decreased histone H3 acetylation at Lys9 and Lys14 (H3K9/K14ac) in the miR-1246 promoter region are essential for the low expression of miR-1246 in SLE B cells. p53 can promote miR-1246 transcription by recruiting Jumonji domain-containing protein 3 (JMJD3), E1A-binding protein p300 (EP300), and CREB-binding protein (CBP) to bind to the miR-1246 promoter, downregulating H3K27me3 and upregulating H3K9/K14ac. Furthermore, early B cell factor 1 (EBF1), CD40, CD38, and X box binding protein-1 (XBP-1) expression levels in SLE B cells transfected with p53 expression plasmid were significantly decreased, whereas autoantibody IgG production in autologous CD4+ T cells cocultured with overexpressed p53 SLE B cells was reduced. Collectively, our data suggest that the reduction of p53 decreases miR-1246 expression via upregulation of H3K27me3 and downregulation of H3K9/14ac, which in turn results in SLE B cell hyperactivity.

Downregulation of the endothelial histone demethylase JMJD3 is associated with neointimal hyperplasia of arteriovenous fistulas in kidney failure

Jumonji domain–containing protein-3 (JMJD3), a histone H3 lysine 27 (H3K27) demethylase, promotes endothelial regeneration, but its function in neointimal hyperplasia (NIH) of arteriovenous fistulas (AVFs) has not been explored. In this study, we examined the contribution of endothelial JMJD3 to NIH of AVFs and the mechanisms underlying JMJD3 expression during kidney failure. We found that endothelial JMJD3 expression was negatively associated with NIH of AVFs in patients with kidney failure. JMJD3 expression in endothelial cells (ECs) was also downregulated in the vasculature of chronic kidney disease (CKD) mice. In addition, specific knockout of endothelial JMJD3 delayed EC regeneration, enhanced endothelial mesenchymal transition, impaired endothelial barrier function as determined by increased Evans blue staining and inflammatory cell infiltration, and accelerated neointima formation in AVFs created by venous end to arterial side anastomosis in CKD mice. Mechanistically, JMJD3 expression was downregulated via binding of transforming growth factor beta 1–mediated Hes family transcription factor Hes1 to its gene promoter. Knockdown of JMJD3 enhanced H3K27 methylation, thereby inhibiting transcriptional activity at promoters of EC markers and reducing migration and proliferation of ECs. Furthermore, knockdown of endothelial JMJD3 decreased endothelial nitric oxide synthase expression and nitric oxide production, leading to the proliferation of vascular smooth muscle cells. In conclusion, we demonstrate that decreased expression of endothelial JMJD3 impairs EC regeneration and function and accelerates neointima formation in AVFs. We propose increasing the expression of endothelial JMJD3 could represent a new strategy for preventing endothelial dysfunction, attenuating NIH, and improving AVF patency in patients with kidney disease.

Emerging roles of JMJD3 in cancer.

Histone lysine methylation plays a key role in gene activation and repression. The trimethylation of histone H3 on lysine-27 (H3K27me3) is a critical epigenetic event that is controlled by Jumonji domain-containing protein-3 (JMJD3). JMJD3 is a histone demethylase that specifically removes methyl groups. Previous studies have suggested that JMJD3 has a dual role in cancer cells. JMJD3 stimulates the expression of proliferative-related genes and increases tumor cell growth, propagation, and migration in various cancers, including neural, prostate, ovary, skin, esophagus, leukemia, hepatic, head and neck, renal, lymphoma, and lung. In contrast, JMJD3 can suppress the propagation of tumor cells, and enhance their apoptosis in colorectal, breast, and pancreatic cancers. In this review, we summarized the recent advances of JMJD3 function in cancer cells.

Phosphatidylserine released from apoptotic cells in tumor induces M2-like macrophage polarization through the PSR-STAT3-JMJD3 axis.

BackgroundUnderstanding how the tumor microenvironment is shaped by various factors is important for the development of new therapeutic strategies. Tumor cells often undergo spontaneous apoptotic cell death in tumor microenvironment, these apoptotic cells are histologically co‐localized with immunosuppressive macrophages. However, the mechanism by which tumor cell apoptosis modulates macrophage polarization is not fully understood. In this study, we aimed to explore the tumor promoting effects of apoptotic tumor cells and the signal pathways involved.MethodsApoptotic cells and macrophages in tumors were detected by immunohistochemical staining. Morphological analysis was performed with Giemsa staining. Lipids generated from apoptotic cells were detected by liquid chromatography‐mass spectrometry. Phosphatidylserine‐containing liposomes were prepared to mimic apoptotic cells. The expression of protein was determined by real‐time PCR, immunohistochemistry enzyme‐linked immunosorbent assay and Western blotting. Mouse malignant ascites and subcutaneous tumor models were designed for in vivo analysis. Transgenic mice with specific genes knocked out and inhibitors specific to certain proteins were used for the mechanistic studies.ResultsThe location and the number of apoptotic cells were correlated with that of macrophages in several types of carcinomas. Phosphatidylserine, a lipid molecule generated in apoptotic cells, induced polarization and accumulation of M2‐like macrophages in vivo and in vitro. Moreover, sustained administration of phosphoserine promoted tumor growth in the malignant ascites and subcutaneous tumor models. Further analyses suggested that phosphoserine induced a M2‐like phenotype in macrophages, which was related to the activation of phosphoserine receptors including T‐cell immunoglobin mucin 4 (TIM4) and the FAK‐SRC‐STAT3 signaling pathway as well as elevated the expression of the histone demethylase Jumonji domain‐containing protein 3 (JMJD3). Administration of specific inhibitors of these pathways could reduce tumor progression.ConclusionsThis study suggest that apoptotic cell‐generated phosphoserine might be a notable signal for immunosuppressive macrophages in tumors, and the related pathways might be potential therapeutic targets for cancer therapy.

H3K27me3 demethylase UTX regulates the differentiation of a subset of bipolar cells in the mouse retina.

Di- and trimethylation of lysine 27 on histone 3 (H3K27me2/3) is a critical gene repression mechanism. We previously showed that down-regulation of the H3K27 demethylase, Jumonji domain-containing protein 3 (JMJD3), resulted in a reduced number of protein kinase C (PKC)α-positive rod ON-bipolar cells. In this work, we focused on the role of another H3K27 demethylase, ubiquitously transcribed tetratricopeptide repeat X chromosome (UTX), in retinal development. UTX was expressed in the retinal progenitor cells of the embryonic mouse retina and was observed in the inner nuclear layer during late retinal development and in the mature retina. The short hairpin RNA-mediated knockdown of Utx in a mouse retinal explant led to a reduced number of PKCα-positive rod ON-bipolar cells. However, other retinal subtypes were unaffected by this knockdown. Using a retina-specific knockout of Utx in mice, the in vivo effects of UTX down-regulation were examined. Again, the number of PKCα-positive rod ON-bipolar cells was reduced, and no other apparent phenotypes, including retinal progenitor proliferation, apoptosis or differentiation, were observed. Finally, we examined retina-specific Utx and Jmjd3 double-knockout mice and found that although the number of rod ON-bipolar cells was reduced, no additional effects from the loss of Utx and Jmjd3 were observed. Taken together, our data show that UTX contributes to retinal differentiation in a lineage-specific manner.

JMJD3 promotes the epithelial-mesenchymal transition and migration of glioma cells via the CXCL12/CXCR4 axis.

Histone H3K27 demethylase Jumonji domain-containing protein 3 (JMJD3) is involved in somatic cell differentiation and tumor progression; however, the underlying mechanisms of JMJD3 in cancer progression are yet to be fully explored. To improve understanding regarding the function of JMJD3 in brain tumor cells, the present study investigated the effects of JMJD3 on the epithelial-mesenchymal transition (EMT) and migration in glioma cells, and the underlying mechanisms involving the C-X-C motif chemokine ligand 12 (CXCL12)/C-X-C motif chemokine receptor 4 (CXCR4) axis. Immunohistochemical staining of a tissue microarray of glioma samples confirmed that JMJD3 overexpression could stratify highly metastatic glioma. The overexpression of JMJD3 induced a spindle-shaped morphology, promoted N-cadherin expression, inhibited E-cadherin expression and enhanced the migration ability of U-251MG and U-87MG American Type Culture Collection cells. The expression of E-cadherin and N-cadherin were assessed by western blotting and reverse transcription-quantitative polymerase chain reaction, and cell migration was evaluated using a Transwell migration assay and wound-healing. The overexpression of JMJD3 upregulated CXCL12 expression in a demethylase activity-dependent manner as ChIP assays revealed a decrease in H3K27 trimethylation at the CXCL12 promoter following overexpression of JMJD3 in U-87MG ATCC cells. Accordingly, CXCL12 overexpression was sufficient to rescue the suppressive effects of JMJD3 inhibition on the EMT and migration in glioma cells. In addition, CXCR4 expression was not regulated by JMJD3, but the interruption of CXCR4 caused by the CXCR4 inhibitor AMD3100 abolished the promotional effect of JMJD3 on EMT and migration in glioma cells. Collectively, these results suggested that JMJD3 promoted EMT and migration in glioma cells via the CXCL12/CXCR4 axis. The present study described a novel epigenetic mechanism regulating tumor cell EMT and migration, and provided a novel direction for glioma diagnosis and treatment.

SUN-210 THE HISTONE DEMETHYLASE JUMONJI DOMAIN-CONTAINING PROTEIN 3 ACTS AS AN EPIGENETIC SUPPRESSOR OF RENAL FIBROSIS

The histone demethylase Jumonji domain-containing protein 3 (JMJD3) is the enzyme that induces demethylation of histone H3 lysine 27 (H3K27) and its activation is involved in the tumor genesis. Although activation of H3K27 methyltransferase has been shown to be required for renal interstitial fibroblast activation and renal fibrogenesis, the role of JMJD3 in these processes remains elusive.

The histone H3 Lys 27 demethylase KDM6B promotes migration and invasion of glioma cells partly by regulating the expression of SNAI1

The histone demethylase KDM6B, also known as jumonji domain-containing protein 3 (JMJD3), is an epigenetic regulator which plays important roles in immune activation, tissue regeneration, cellular senescence and cancer metastasis. But, the role of KDM6B in glioma metastasis is poorly understood. In this study, we achieved transcriptional regulation of KDM6B in glioma cells using CRISPR interference (CRISPRi) and CRISPR activation (CRISPRa). Our results showed that KDM6B promotes the proliferation, migration and invasion of human glioblastoma cells U87 and U251 using CCK8, scratch and transwell assays. Further results indicated that KDM6B increases the expression of SNAI1, a key factor of epithelial-mesenchymal transition (EMT). KDM6B catalyzes the demethylation of histone H3 Lys 27 trimethylation (H3K27me3) in the promoter of SNAI1, which is important for SNAI1 upregulation. Taken together, these findings provide new insight into the mechanism by which KDM6B promotes glioma metastasis.

Notch signaling promotes serrated neoplasia pathway in colorectal cancer through epigenetic modification of EPHB2 and EPHB4.

BackgroundDysregulation of erythropoietin-producing hepatoma (Eph) proteins in human cancers is extensively documented but not clear in colorectal cancer (CRC). In this study, we aimed to investigate the role of Notch signaling pathway and epigenetic modification of EPHB2 and EPHB4 expression in serrated neoplasia development.MethodsThe expression of EPHB2 and EPHB4 in CRC clinical specimens and cell lines were determined by immunohistochemistry, Western blot, and real-time PCR. Cell proliferation and invasion were evaluated by MTT and chamber kits, luciferase assay and co-immunoprecipitation were used to detect the transcriptional regulation and protein–protein interactions, respectively. The immunofluorescence assay was employed to confirm the subcellular location of Notch intracellular domain (NICD), and chromatin immunoprecipitation assay was implied to detect the modification types of H3K4me3 and H3K27me3. Mice xenograft model was used to detect the in vivo effects of EPHB2 and EPHB4 genes on cell growth.ResultsIn CRC clinical specimens and cell lines, we found that EPHB2 was significantly decreased, while EPHB4 was elevated in the CRC tissues, and these aberrant expression manners correlated with worse overall survival rates in the clinic. When the EPHB2 and EPHB4 expressions were manipulated by overexpression or knockdown in the SW620 cells, the cell proliferation and invasion were obviously suppressed, whereas EPHB2 knockdown or EPHB4 overexpression showed the opposite phenotypes. We also found that Notch signaling pathway was abnormally activated and treatment of Notch signaling ligand human Jagged1 peptide downregulated EPHB2 and upregulated EPHB4 in the SW620 cells, as well as promoted the chromatin modification protein Jumonji domain-containing protein-3 (JMJD3) cytonuclear trans-localization with the NICD, which indicated that NICD brought JMJD3 to the EPHB4 enhancer region to decrease the H3K27me3 level.ConclusionTaken together, we provide a new mechanistic option in understanding the role of Notch signaling and the roles of EPHB2 and EPHB4 in CRC.