Cooperation between KDM6B overexpression and TET2 deficiency in the pathogenesis of chronic myelomonocytic leukemia.

Loss-of-function TET2 mutations are recurrent somatic lesions in chronic myelomonocytic leukemia (CMML). KDM6B encodes a histone demethylase involved in innate immune regulation that is overexpressed in CMML. We conducted genomic and transcriptomic analyses in treatment naïve CMML patients and observed that the patients carrying both TET2 mutations and KDM6B overexpression constituted 18% of the cohort and 42% of patients with TET2 mutations. We therefore hypothesized that KDM6B overexpression cooperated with TET2 deficiency in CMML pathogenesis. We developed a double-lesion mouse model with both aberrations, and discovered that the mice exhibited a more prominent CMML-like phenotype than mice with either Tet2 deficiency or KDM6B overexpression alone. The phenotype includes monocytosis, anemia, splenomegaly, and increased frequencies and repopulating activity of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs). Significant transcriptional alterations were identified in double-lesion mice, which were associated with activation of proinflammatory signals and repression of signals maintaining genome stability. Finally, KDM6B inhibitor reduced BM repopulating activity of double-lesion mice and tumor burden in mice transplanted with BM-HSPCs from CMML patients with TET2 mutations. These data indicate that TET2 deficiency and KDM6B overexpression cooperate in CMML pathogenesis of and that KDM6B could serve as a potential therapeutic target in this disease.

The Epigenetic Regulator Jumonji Domain-Containing Protein 6 (JMJD6) Is Highly Expressed but Not Prognostic in IDH-Wildtype Glioblastoma Patients.

Patients with IDH-wildtype glioblastoma (GBM) generally have a poor prognosis. However, there is an increasing need of novel robust biomarkers in the daily clinico-pathological setting to identify and support treatment in patients who become long-time survivors. Jumonji domain-containing protein 6 (JMJD6) is involved in epigenetic regulation of demethylation of histones and has been associated with GBM aggressiveness. We investigated the expression and prognostic potential of JMJD6 tumor fraction score in 184 IDH-wildtype GBMs. Whole-slides were double-stained with an antibody against JMJD6 and an exclusion-cocktail consisting of 4 antibodies (CD31, SMA, CD45, and Iba-1), enabling evaluation of tumor cells only. Stainings were quantified with a combined software- and scoring-based approach. For comparison, IDH-mutated WHO grade II, III and IV astrocytic gliomas were also stained, and the JMJD6 tumor fraction score increased with increasing WHO grade, although not significantly. In multivariate analysis including age, gender, performance status and post-surgical treatment high JMJD6 tumor fraction score was associated with longer overall survival in IDH-wildtype GBMs (p = 0.03), but the effect disappeared when MGMT promoter status was included (p = 0.34). We conclude that JMJD6 is highly expressed in IDH-wildtype GBM but it has no independent prognostic value.

Lysine Demethylase 6B Regulates Prostate Cancer Cell Proliferation by Controlling c-MYC Expression.

Elevated expression of lysine demethylase 6A (KDM6A) and lysine demethylase 6B (KDM6B) has been reported in prostate cancer (PCa). However, the mechanism underlying the specific role of KDM6A/B in PCa is still fragmentary. Here, we report novel KDM6A/B downstream targets involved in controlling PCa cell proliferation. KDM6A and KDM6B mRNAs were higher in prostate adenocarcinoma, lymph node metastatic site (LNCaP) but not in prostate adenocarcinoma, bone metastatic site (PC3) and prostate adenocarcinoma, brain metastatic site (DU145) cells. Higher KDM6A mRNA was confirmed at the protein level. A metastasis associated gene focused oligonucleotide array was performed to identify KDM6A/B dependent genes in LNCaP cells treated with a KDM6 family selective inhibitor, ethyl-3-(6-(4,5-dihydro-1H-benzo[d]azepin-3(2H)-yl)-2-(pyridin-2-yl)pyrimidin-4-ylamino)propanoate (GSK-J4). This identified five genes [V-myc myelocytomatosis viral oncogene homolog (avian) (c-MYC), neurofibromin 2 (merlin) (NF2), C-terminal binding protein 1 (CTBP1), EPH receptor B2 (EPHB2), and plasminogen activator urokinase receptor (PLAUR)] that were decreased more than 50% by GSK-J4, and c-MYC was the most downregulated gene. Array data were validated by quantitative reverse transcription polymerase chain reaction (qRT-PCR), which detected a reduction in c-MYC steady state mRNA and prespliced mRNA, indicative of transcriptional repression of c-MYC gene expression. Furthermore, c-MYC protein was also decreased by GSK-J4. Importantly, GSK-J4 reduced mRNA and protein levels of c-MYC target gene, cyclinD1 (CCND1). Silencing of KDM6A/B with small interfering RNA (siRNA) confirmed that expression of both c-MYC and CCND1 are dependent on KDM6B. Phosphorylated retinoblastoma (pRb), a marker of G1 to S-phase transition, was decreased by GSK-J4 and KDM6B silencing. GSK-J4 treatment resulted in a decrease in cell proliferation and cell number, detected by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay and conventional cell counting, respectively. Consequently, we conclude that KDM6B controlling c-MYC, CCND1, and pRb contribute regulation of PCa cell proliferation, which represents KDM6B as a promising epigenetic target for the treatment of advanced PCa. SIGNIFICANCE STATEMENT: Lysine demethylase 6A (KDM6A) and 6B (KDM6B) were upregulated in prostate cancer (PCa). We reported novel KDM6A/B downstream targets controlling proliferation. Amongst 84 metastasis associated genes, V-myc myelocytomatosis viral oncogene homolog (avian) (c-MYC) was the most inhibited gene by KDM6 inhibitor, ethyl-3-(6-(4,5-dihydro-1H-benzo[d]azepin-3(2H)-yl)-2-(pyridin-2-yl)pyrimidin-4-ylamino)propanoate (GSK-J4). This was accompanied by decreased c-MYC targets, cyclinD1 (CCND1) and phosphorylated retinoblastoma (pRb), which were KDM6B dependent. GSK-J4 decreased proliferation and cell counting. We conclude that KDM6B controlling c-MYC, CCND1, and pRb contribute regulation of PCa proliferation.

Histone demethylase KDM4A overexpression improved the efficiency of corrected human tripronuclear zygote development.

Human zygotes are difficult to obtain for research because of limited resources and ethical debates. Corrected human tripronuclear (ch3PN) zygotes obtained by removal of the extra pronucleus from abnormally fertilized tripronuclear (3PN) zygotes are considered an alternative resource for basic scientific research. In the present study, eight-cell and blastocyst formation efficiency were significantly lower in both 3PN and ch3PN embryos than in normal fertilized (2PN) embryos, while histone H3 lysine 9 trimethylation (H3K9me3) levels were much higher. It was speculated that the aberrant H3K9me3 level detected in ch3PN embryos may be related to low developmental competence. Microinjection of 1000 ng/µl lysine-specific demethylase 4A (KDM4A) mRNA effectively reduced the H3K9me3 level and significantly increased the developmental competence of ch3PN embryos. The quality of ch3PN zygotes improved as the grading criteria, cell number and pluripotent expression significantly increased in response to KDM4A mRNA injection. Developmental genes related to zygotic genome activation (ZGA) were also upregulated. These results indicate that KDM4A activates the transcription of the ZGA program by enhancing the expression of related genes, promoting epigenetic modifications and regulating the developmental potential of ch3PN embryos. The present study will facilitate future studies of ch3PN embryos and could provide additional options for infertile couples.

High Expression of JMJD4 Is a Potential Diagnostic and Prognostic Marker of Renal Cell Carcinoma.

Histone demethylase JMJD4 is a burgeoning tumor marker, which has been proven to be associated with colon cancer, but the role it plays in kidney cancer has not yet been investigated. In the present study, we evaluated whether JMJD4 can be a prognostic marker of patients with clear cell renal cell carcinoma (ccRCC) using data from public platform and in vitro experiments. Our results revealed that the expression of JMJD4 is higher in cancerous tissue than in normal tissues (p < 0.001). High expression of JMJD4 is associated with a poor overall survival (OS) of ccRCC as compared with low expression of JMJD4 (p = 0.015). JMJD4 showed significant relevance with M stage (p = 0.016), gender (p = 0.003), OS (0.018), disease-specific survival (DSS) (0.007), and percussion free interval (PFI) (0.041). Univariate and multivariate Cox analyses demonstrated that high JMJD4 expression had independent predictive value for OS in ccRCC patients (hazard ratio (HR) = 1.563, 95%confidence interval (CI) = 1.055-2.316, and p = 0.026). Besides, in vitro experiments confirmed that high expression of JMJD4 can significantly promote the invasion ability (p < 0.001), cloning ability (p < 0.001), and proliferation (p < 0.001) of renal cell carcinoma. In summary, high JMJD4 expression may be a prognostic marker in patients with kidney cancer.

JHDM1D-AS1 aggravates the development of gastric cancer through miR-450a-2-3p-PRAF2 axis.

AIMS: To investigate the molecular function and mechanisms of JHDM1D antisense 1 (JHDM1D-AS1) during gastric cancer (GC) progression. MATERIALS AND METHODS: The qPCR assay was used to detect the JHDM1D-AS1 and miR-450a-2-3p expression levels in GC tissues and cell lines. Bioinformatics analysis was used for exploring the lncRNA-microRNA-mRNA interaction network. We performed dual-luciferase reporter assay and qPCR assay in order to validate the direct interactions. We explored the JHDM1D-AS1 and miR-450a-2-3p on GC progression by using JHDM1D-AS1 siRNA and miR-450a-2-3p inhibitor; in vitro CCK-8 assay, colony formation assay, and invasion assay were conducted. Further, in vivo animal experiments were performed, and the expression levels of miR-450a-2-3p and PRAF2 in the tumor tissues were detected using qPCR and western blot analysis. KEY FINDINGS: The expression levels of JHDM1D-AS1 and miR-450a-2-3p in GC tissues and cell lines were higher and lower as compared to those in the corresponding normal controls, respectively. Moreover, high levels of JHDM1D-AS1 were closely related with metastasis and the GC TNM stage. Functionally, JHDM1D-AS1 depletion caused an obvious reduction in cell proliferation and invasion both in vitro and in vivo, while the addition of miR-450a-2-3p inhibitor could nullify these effects. Mechanically, JHDM1D-AS1 promoted GC progression via the sponging of miR-450a-2-3p in order to increase PRAF2 expression. SIGNIFICANCE: The present results showed that the increased expression of JHDM1D-AS1 was closely associated with tumor progression of GC. JHDM1D-AS1/miR-450a-2-3p/PRAF2 axis may be a promising target for GC treatment.

Jmjd3 Plays Pivotal Roles in the Proper Development of Early-Born Retinal Lineages: Amacrine, Horizontal, and Retinal Ganglion Cells.

Purpose: Trimethylation of histone H3 at lysine 27 (H3K27me3) is a critical mediator of transcriptional gene repression, and Jmjd3 and Utx are the demethylases specific to H3K27me3. Using an in vitro retinal explant culture system, we previously revealed the role of Jmjd3 in the development of rod bipolar cells; however, the roles of Jmjd3 in the development of early-born retinal cells are unknown due to limitations concerning the use of retinal explant culture systems. In this study, we investigated the roles of Jmjd3 in the development of early-born retinal cells. Methods: We examined retina-specific conditional Jmjd3 knockout (Jmjd3-cKO) mice using immunohistochemistry and quantitative reverse transcription PCR and JMJD3 binding to a target locus by chromatin immunoprecipitation analysis. Results: We observed reductions in amacrine cells (ACs) and horizontal cells (HCs), as well as lowered expression levels of several transcription factors involved in the development of ACs and HCs in the Jmjd3-cKO mouse retina. JMJD3 bound the promoter regions of these transcription factors. Notably, an elevated number of retinal ganglion cells (RGCs) was observed at embryonic stages, whereas RGCs were moderately reduced at later postnatal stages in the Jmjd3-cKO retina. We also observed reduced expression of Eomes, which is required for the maintenance of RGCs, as well as lower H3K27me3 level and lower JMJD3 binding in the promoter region of Eomes in RGC-enriched cells. Conclusions: The results indicated that Jmjd3 has critical roles in the development of early-born retinal subtypes, and suggested biphasic roles of Jmjd3 in RGC production and maintenance.

Upregulation of JMJD2A promotes migration and invasion in bladder cancer through regulation of SLUG.

Jumonji domain­containing protein 2A (JMJD2A) has been identified to promote cell proliferation in bladder cancer; however, it remains undetermined whether JMJD2A regulates cell migration and invasion in bladder cancer. The aim of the present study was to further investigate the roles of JMJD2A in bladder cancer. The expression levels of JMJD2A in bladder cancer tissues and cell lines were established by RT­qPCR assays and western blot analysis. Moreover, by gain­ and loss­of­function assays, the effects of JMJD2A on migration and invasion as well as proliferation were investigated in bladder cancer cells. The results revealed that the expression level of JMJD2A was significantly upregulated in bladder cancer tissues and cell lines compared to adjacent non­tumor tissues and a human immortalized bladder urothelial cell line. Kaplan­Meier survival analysis indicated that patients with high JMJD2A expression level had shorter overall survival. Moreover, JMJD2A could promote cell migration and invasion by facilitating epithelial­mesenchymal transition (EMT) in bladder cancer. In addition, it was determined that JMJD2A promoted EMT through regulation of SLUG expression. Collectively, our findings revealed that JMJD2A may act as an oncogene and participate in bladder cancer progression, which provides a promising therapeutic strategy for patients with bladder cancer.

Targeting the H3K4 Demethylase KDM5B Reprograms the Metabolome and Phenotype of Melanoma Cells.

Melanoma cells shift between epigenetic-metabolic states to adapt to stress and, particularly, to drugs. Here, we unraveled the metabolome of an H3K4 demethylase (KDM5B/JARID1B)-driven melanoma cell phenotype that is known to be multidrug resistant. We set up a fast protocol for standardized, highly sensitive liquid chromatography-high resolution mass spectrometry analyzing stably controlled KDM5B expression by RNAi or doxycycline-induced overexpression. Within the KDM5B-dependent metabolome, we found significant and highly specific regulation of 11 intracellular metabolites. Functionally, overexpression of KDM5B in melanoma cells led to broadening of their oxidative metabolism from mainly glutamine-dependent to additionally glucose- and fatty acid-utilizing, upregulation of the pentose phosphate pathway as a source of antioxidant NADPH, and maintenance of a high ratio of reduced to oxidized glutathione. Histone lysine demethylase inhibition (GSK-J1, 2,4-PDCA) decreased colony formation and invasion in three-dimensional models. Thus, targeting KDM5B could represent an alternative way of modulating the metabolome and malignant cell behavior in melanoma.

Elevated endothelial Sox2 causes lumen disruption and cerebral arteriovenous malformations.

Lumen integrity in vascularization requires fully differentiated endothelial cells (ECs). Here, we report that endothelial-mesenchymal transitions (EndMTs) emerged in ECs of cerebral arteriovenous malformation (AVMs) and caused disruption of the lumen or lumen disorder. We show that excessive Sry-box 2 (Sox2) signaling was responsible for the EndMTs in cerebral AVMs. EC-specific suppression of Sox2 normalized endothelial differentiation and lumen formation and improved the cerebral AVMs. Epigenetic studies showed that induction of Sox2 altered the cerebral-endothelial transcriptional landscape and identified jumonji domain-containing protein 5 (JMJD5) as a direct target of Sox2. Sox2 interacted with JMJD5 to induce EndMTs in cerebral ECs. Furthermore, we utilized a high-throughput system to identify the ß-adrenergic antagonist pronethalol as an inhibitor of Sox2 expression. Treatment with pronethalol stabilized endothelial differentiation and lumen formation, which limited the cerebral AVMs.

SNHG1 promotes malignant biological behaviors of glioma cells via microRNA-154-5p/miR-376b-3p- FOXP2- KDM5B participating positive feedback loop.

BACKGROUND: Long non-coding RNAs has been reported in tumorigenesis and play important roles in regulating malignant behavior of cancers, including glioma. METHODS: According to the TCGA database, we identified SNHG1, miRNA-154-5p and miR-376b-3p whose expression were significantly changed in the glioma samples. Furthermore, we investigated SNHG1, miRNA-154-5p and miR-376b-3p expression in clinical samples and glioma cell lines using qRT-PCR analysis and the correlation between them using RNA immunoprecipitation and dual-luciferase reporter. The underlying mechanisms of SNHG1 in glioma were also investigated using immunohistochemistry staining, Western blotting, chromatin immunoprecipitation, and RNA pulldown. Cell Counting Kit-8, transwell assays, and flow cytometry were used to investigate malignant biological behaviors. RESULTS: We have elucidated the potential molecular mechanism of long non-coding RNA SNHG1 regulating the malignant behavior of glioma cells by binding to microRNA-154-5p or miR-376b-3p. Moreover, our deep-going results showed that FOXP2 existed as a direct downstream target of both microRNA-154-5p and miR-376b-3p; FOXP2 increased promoter activities and enhanced the expression of the oncogenic gene KDM5B; and KDM5B also acts as a RNA-binding protein to maintain the stability of SNHG1. CONCLUSION: Collectively, this study demonstrates that the SNHG1- microRNA-154-5p/miR-376b-3p- FOXP2- KDM5B feedback loop plays a pivotal role in regulating the malignant behavior of glioma cells.

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.

Interplay among H3K9-editing enzymes SUV39H1, JMJD2C and SRC-1 drives p66Shc transcription and vascular oxidative stress in obesity.

Aims: Accumulation of reactive oxygen species (ROS) promotes vascular disease in obesity, but the underlying molecular mechanisms remain poorly understood. The adaptor p66Shc is emerging as a key molecule responsible for ROS generation and vascular damage. This study investigates whether epigenetic regulation of p66Shc contributes to obesity-related vascular disease. Methods and results: ROS-driven endothelial dysfunction was observed in visceral fat arteries (VFAs) isolated from obese subjects when compared with normal weight controls. Gene profiling of chromatin-modifying enzymes in VFA revealed a significant dysregulation of methyltransferase SUV39H1 (fold change, -6.9, P < 0.01), demethylase JMJD2C (fold change, 3.2, P < 0.01), and acetyltransferase SRC-1 (fold change, 5.8, P < 0.01) in obese vs. control VFA. These changes were associated with reduced di-(H3K9me2) and trimethylation (H3K9me3) as well as acetylation (H3K9ac) of histone 3 lysine 9 (H3K9) on p66Shc promoter. Reprogramming SUV39H1, JMJD2C, and SRC-1 in isolated endothelial cells as well as in aortas from obese mice (LepOb/Ob) suppressed p66Shc-derived ROS, restored nitric oxide levels, and rescued endothelial dysfunction. Consistently, in vivo editing of chromatin remodellers blunted obesity-related vascular p66Shc expression. We show that SUV39H1 is the upstream effector orchestrating JMJD2C/SRC-1 recruitment to p66Shc promoter. Indeed, SUV39H1 overexpression in obese mice erased H3K9-related changes on p66Shc promoter, while SUV39H1 genetic deletion in lean mice recapitulated obesity-induced H3K9 remodelling and p66Shc transcription. Conclusion: These results uncover a novel epigenetic mechanism underlying endothelial dysfunction in obesity. Targeting SUV39H1 may attenuate oxidative transcriptional programmes and thus prevent vascular disease in obese individuals.

Unraveling KDM4 histone demethylase expression and its association with adverse cytogenetic findings in chronic lymphocytic leukemia.

The acquisition of complex karyotypes is related to the progression of chronic lymphocytic leukemia (CLL) and patients with this condition have a poor prognosis. Despite recent advances in the classification of prognosis in CLL patients, understanding of the molecular mechanisms that lead to genomic instability and progression of this disease remains inadequate. Interestingly, dysregulated expression of KDM4 members is involved in the progression of several cancer types and plays a role in the DNA damage response; however, the gene expression profile and the importance of KDM4 members in CLL are still unknown. Here, we assessed the gene expression profile of KDM4A, KDM4B, and KDM4C in 59 CLL samples and investigated whether these histone demethylases have any influence on the prognostic markers of this leukemia. KDM4A gene expression was higher in CLL patients as compared with control samples. In contrast, CLL samples showed decreased levels of the KDM4B transcript in relation to control cases, and no difference was detected in KDM4C expression. Furthermore, patients with positive expression of ZAP-70 had lower expression of KDM4B and KDM4C as compared with ZAP-70-negative patients. More importantly, patients with low expression of these histone demethylases had higher leukemic cell numbers and displayed adverse cytogenetic findings and the acquisition of a complex karyotype. The present data clearly show that the expression of KDM4 members is dysregulated in CLL and impact the prognosis of this leukemia. These findings are useful for a better understanding of the impact of epigenetics on CLL progression.

Therapeutic potential of GSK-J4, a histone demethylase KDM6B/JMJD3 inhibitor, for acute myeloid leukemia.

PURPOSE: Acute myeloid leukemia (AML) is a heterogeneous disease with poor outcomes. Despite increased evidence shows that dysregulation of histone modification contributes to AML, specific drugs targeting key histone modulators are not applied in the clinical treatment of AML. Here, we investigated whether targeting KDM6B, the demethylase of tri-methylated histone H3 lysine 27 (H3K27me3), has a therapeutic potential for AML. METHODS: A KDM6B-specific inhibitor, GSK-J4, was applied to treat the primary cells from AML patients and AML cell lines in vitro and in vivo. RNA-sequencing was performed to reveal the underlying mechanisms of inhibiting KDM6B for the treatment of AML. RESULTS: Here we observed that the mRNA expression of KDM6B was up-regulated in AML and positively correlated with poor survival. Treatment with GSK-J4 increased the global level of H3K27me3 and reduced the proliferation and colony-forming ability of primary AML cells and AML cell lines. GSK-J4 treatment significantly induced cell apoptosis and cell-cycle arrest in Kasumi-1 cells, and displayed a synergistic effect with cytosine arabinoside. Notably, injection of GSK-J4 attenuated the disease progression in a human AML xenograft mouse model in vivo. Treatment with GSK-J4 predominantly resulted in down-regulation of DNA replication and cell-cycle-related pathways, as well as abrogated the expression of critical cancer-promoting HOX genes. ChIP-qPCR validated an increased enrichment of H3K27me3 in the transcription start sites of these HOX genes. CONCLUSIONS: In summary, our findings suggest that targeting KDM6B with GSK-J4 has a therapeutic potential for the treatment of AML.

FBXL10 contributes to the development of diffuse large B-cell lymphoma by epigenetically enhancing ERK1/2 signaling pathway.

Epigenetic modifiers have emerged as critical factors governing the biology of different cancers. Herein we show that FBXL10 (also called KDM2B or JHDM1B), an important member of Polycomb repressive complexes, is overexpressed in human diffuse large B-cell lymphoma (DLBCL) tissues and the derived cell lines. Knocking down FBXL10 by specific short hairpin RNAs in DLBCL cells inhibits cell proliferation and induces apoptosis in vitro. Moreover, FBXL10 depletion in DLBCL cells abrogates tumor growth in mouse xenograft models. Through the analysis of RNA sequencing, we find that one of the key derepressed genes by depletion of FBXL10 is DUSP6, encoding a phosphatase for ERK1/2. Mechanistically FBXL10 maintains the silencing of DUSP6 expression via recruitment of Polycomb group proteins and deposition of repressive histone modifications at the DUSP6 promoter. Consistently, FBXL10 is required for ERK1/2 phosphorylation in DLBCL cells. Furthermore, we show that ERK1/2 activation and the proliferation rate of FBXL10-depleted cells can be rescued by downregulation of DUSP6 expression. These findings indicate that FBXL10 may be a promising therapeutic target in DLBCL and establish a link of epigenetic regulators to kinase signaling pathways.

KDM6 and KDM4 histone lysine demethylases emerge as molecular therapeutic targets in human acute myeloid leukemia.

Acute myeloid leukemia (AML) remains an aggressive hematopoietic malignancy that is caused by proliferation of immature myeloid cells and is frequently characterized by perturbations in chromatin-modifying enzymes. Emerging evidence indicates that histone demethylases play a role in tumorigenesis. However, due to the complexity of this enormous family of histone-modifying enzymes, substrate redundancy, and context-specific roles, the contribution of each member remains ambiguous and targeting them remains challenging. Here, we analyzed expression of histone-3-lysine (H3K) demethylases and their cognate substrates in a cohort of de novo AML patients, which demonstrated that the expression of H3K27Me3/2-demethylases and selected members of H3K9Me3/2/1-demethylases are significantly increased in AML. KDM6 upregulation is associated with a global decrease in H3K27Me3 level. Importantly, our data show that pharmacological inhibition of H3K27Me3/2-demethylases or H3K9Me3/2-demethylases, either alone or in combination, could be considered an interesting molecular therapeutic modality in human AML independent of its subtype.

RANKL-mediated harmonious dialogue between fetus and mother guarantees smooth gestation by inducing decidual M2 macrophage polarization.

Decidual macrophages (dMϕ) contribute to maternal-fetal tolerance. However, the mechanism of dMϕ differentiation during pregnancy is still largely unknown. Here, we report that receptor activator for nuclear factor-κ B ligand (RANKL), secreted by human embryonic trophoblasts and maternal decidual stromal cells (DSCs), polarizes dMϕ toward a M2 phenotype. This polarization is mediated through activation of Akt/signal transducer and activator of transcription 6 (STAT6) signaling, which is associated with the upregulation of histone H3 lysine-27 demethylase Jmjd3 and IRF4 in dMϕ. Such differentiated dMϕ can induce a Th2 bias that promotes maternal-fetal tolerance. Impaired expression of RANKL leads to dysfunction of dMϕ in vivo and increased rates of fetal loss in mice. Transfer of RANK+Mϕ reverses mouse fetal loss induced by Mϕ depletion. Compared with normal pregnancy, there are abnormally low levels of RANKL/RANK in villi and decidua from miscarriage patients. These results suggest that RANKL is a pivotal regulator of maternal-fetal tolerance by licensing dMϕ to ensure a successful pregnancy outcome. This observation provides a scientific basis on which a potential therapeutic strategy can be targeted to prevent pregnancy loss.

MiR-770 inhibits tumorigenesis and EMT by targeting JMJD6 and regulating WNT/ß-catenin pathway in non-small cell lung cancer.

AIMS: MicroRNAs (miRNAs) plays important role in development and disease, especially in cancer including non-small cell lung cancer (NSCLC). However, the role of miR-770 in NSCLC remains unclear. In this study, we aimed to study the function and mechanism of miR-770 in tumorigenesis of NSCLC. MAIN METHODS: RT-qPCR was used to measure the expression levels of miR-770 in NSCLC tissues and cells. MTT assay, colony formation assay, flow cytometric analysis and transwell migration and invasion assays were performed to investigate the role of miR-770 in NSCLC cells. Bioinformatics and luciferase reporter analyses were used to demonstrate that whether the Jumonji domain-containing 6 (JMJD6) as a direct target of miR-770. The function of JMJD6 in NSCLC was also investigated. Finally, in vivo animal experiment was used to study whether miR-770 was capable of inhibiting tumor growth by inhibiting JMJD6. KEY FINDINGS: We first showed that miR-770 was downregulated in NSCLC tissues and cell lines, and the low expression of miR-770 was correlated with poor patient survival in NSCLC patients. miR-770 acted on a tumor suppressor by binding to the 3'UTR of JMJD6 and downregulated its expression in NSCLC cells. This study also demonstrated that JMJD6 played as an oncogene in NSCLC cells. miR-770 overexpression was capable of inhibiting NSCLC tumor growth by inhibiting JMJD6 and its downstream WNT/ß-catenin pathway both in vitro and in vivo. SIGNIFICANCE: The present study indicated that miR-770 functioned as a tumor suppressor and it might be a potential biomarker and therapeutic target in NSCLC.

Immunohistochemical investigation of topoIIß, H3K27me3 and JMJD3 expressions in medulloblastoma.

Topoisomerase IIß (topoIIß) is a nuclear enzyme specifically expressed in neurons, and plays an important role in the development of the cerebellum. To date, the expression of topoIIß protein in medulloblastoma (MB) has not been investigated. In this study, 16 MB specimens including 10 classical subtypes of MB and 6 desmoplastic subtypes of MB (DMB), along with 5 normal cerebellum samples, were obtained from clinics. With immunohistochemical staining, prominently expressed topoIIß was seen in normal cerebellar tissues, while there was no or less pronounced staining in classical MB cells. Interestingly, on comparing topoIIß expression in different regions of DMB samples, relatively high levels of topoIIß were revealed within nodules composed of differentiated neurocytic cells, which are known to predict a favorable clinical outcome for MB. We also examined the expression of two epigenetic factors, H3K27me3 and JMJD3 in the different tissues. Very high levels of H3K27me3 were found in all MB samples, except the intranodules of DMB, where JMJD3 expression was more prominent. Furthermore, a negative correlation between topoIIß and H3K27me3 in MB was revealed in this study. Thus, our data primarily indicate that topoIIß can be used to estimate neuronal differentiation in MB, and may serve as a target for improving the survival rates for this condition. We speculate that H3K27me3 repression of topoIIß at the transcriptional level may occur, although this needs to be verified using larger numbers of MB samples in future experiments.