Refractory testicular germ cell tumors are highly sensitive to the targeting of polycomb pathway demethylases KDM6A and KDM6B.

Testicular germ cell tumors (TGCTs) can be treated with cisplatin-based therapy. However, a clinically significant number of cisplatin-resistant patients die from progressive disease as no effective alternatives exist. Curative cisplatin therapy results in acute and life-long toxicities in the young TGCT patient population providing a rationale to decrease cisplatin exposure. In contrast to genetic alterations, recent evidence suggests that epigenetics is a major driving factor for TGCT formation, progression, and response to chemotherapy. Hence, targeting epigenetic pathways with "epidrugs" is one potential relatively unexplored strategy to advance TGCT treatment beyond cisplatin. In this report, we demonstrate for the first time that targeting polycomb demethylases KDM6A and KDM6B with epidrug GSK-J4 can treat both cisplatin-sensitive and -resistant TGCTs. While GSK-J4 had minimal effects alone on TGCT tumor growth in vivo, it dramatically sensitized cisplatin-sensitive and -resistant TGCTs to cisplatin. We validated KDM6A/KDM6B as the target of GSK-J4 since KDM6A/KDM6B genetic depletion had a similar effect to GSK-J4 on cisplatin-mediated anti-tumor activity and transcriptome alterations. Pharmacologic and genetic targeting of KDM6A/KDM6B potentiated or primed the p53-dominant transcriptional response to cisplatin, with also evidence for basal activation of p53. Further, several chromatin modifier genes, including BRD4, lysine demethylases, chromodomain helicase DNA binding proteins, and lysine methyltransferases, were repressed with cisplatin only in KDM6A/KDM6B-targeted cells, implying that KDM6A/KDM6B inhibition sets the stage for extensive chromatin remodeling of TGCT cells upon cisplatin treatment. Our findings demonstrate that targeting polycomb demethylases is a new potent pharmacologic strategy for treating cisplatin resistant TGCTs that warrants clinical development.

Superficial ice and deep blaze: A defense strategy of the skin.

It's crucial for skin to establish efficient defense strategies. Liu et al. reveal that the transcription factor ZNF750 recruits the histone demethylase KDM1A to silence pattern recognition receptors in the outer epidermis, making their expression limited to deeper, undifferentiated keratinocytes to address threats penetrating the skin.

LMK235 ameliorates inflammation and fibrosis after myocardial infarction by inhibiting LSD1-related pathway.

BACKGROUND: Histone deacetylase 4 (HDAC4) and histone deacetylase 5 (HDAC5) are two isoforms of class IIa HDACs, and LMK235 is an HDAC inhibitor with higher selectivity for HDAC4/5. This study aimed to explore the expression and subcellular localization of HDAC4/5 and determine the mechanisms underlying the impact of LMK235 on ventricular remodelling post-MI. METHODS: The MI model was established by left anterior descending branch (LAD) ligation, and LMK235 or vehicle was intraperitoneally injected daily for 21 days. Cardiac function was determined by echocardiography. Inflammation was evaluated by HE staining and measuring inflammatory cytokine expression, and fibrosis was evaluated by Masson staining and measuring fibrotic biomarker expression. RESULTS: We found that LMK235 ameliorated cardiac dysfunction post-MI by suppressing inflammation and fibrosis, and LMK235 inhibited upregulation of lysine-specific demethylase 1 (LSD1) expression post-MI. In macrophages, LMK235 attenuated lipopolysaccharide (LPS) - induced inflammatory cytokine expression and inhibited LSD1 expression, while overexpression of LSD1 abrogated the anti-inflammatory effect of LMK235. In cardiac fibroblasts, LMK235 attenuated transforming growth factor-ß1 (TGF-ß1) - induced fibrotic biomarker expression and inhibited LSD1 expression, while overexpression of LSD1 abrogated the antifibrotic effect of LMK235. CONCLUSION: LMK235 attenuates chronic inflammation and fibrosis post-MI, leading to improved cardiac function. The anti-inflammatory effect of LMK235 may result from inhibition of the LSD1-NF-κB pathway in macrophages. The antifibrotic effect of LMK235 may result from inhibition of the LSD1-Smad2/3 pathway in cardiac fibroblasts.

The transcription regulators ZNF750 and LSD1/KDM1A dampen inflammation on the skin's surface by silencing pattern recognition receptors.

The surface of the skin is continually exposed to pro-inflammatory stimuli; however, it is unclear why it is not constantly inflamed due to this exposure. Here, we showed undifferentiated keratinocytes residing in the deep epidermis could trigger a strong inflammatory response due to their high expression of pattern recognition receptors (PRRs) that detect damage or pathogens. As keratinocytes differentiated, they migrated outward toward the surface of the skin and decreased their PRR expression, which led to dampened immune responses. ZNF750, a transcription factor expressed only in differentiated keratinocytes, recruited the histone demethylase KDM1A/LSD1 to silence genes coding for PRRs (TLR3, IFIH1/MDA5, and DDX58/RIG1). Loss of ZNF750 or KDM1A in human keratinocytes or mice resulted in sustained and excessive inflammation resembling psoriatic skin, which could be restored to homeostatic conditions upon silencing of TLR3. Our findings explain how the skin's surface prevents excessive inflammation through ZNF750- and KDM1A-mediated suppression of PRRs.

Iron-loaded cancer-associated fibroblasts induce immunosuppression in prostate cancer.

Iron is an essential biomineral in the human body. Here, we describe a subset of iron-loaded cancer-associated fibroblasts, termed as FerroCAFs, that utilize iron to induce immunosuppression in prostate cancer and predict an unfavorable clinical outcome. FerroCAFs secrete myeloid cell-associated proteins, including CCL2, CSF1 and CXCL1, to recruit immunosuppressive myeloid cells. We report the presence of FerroCAFs in prostate cancer from both mice and human, as well as in human lung and ovarian cancers, and identify a conserved cell surface marker, the poliovirus receptor. Mechanistically, the accumulated iron in FerroCAFs is caused by Hmox1-mediated iron release from heme degradation. The intracellular iron activates the Kdm6b, an iron-dependent epigenetic enzyme, to induce an accessible chromatin state and transcription of myeloid cell-associated protein genes. Targeting the FerroCAFs by inhibiting the Hmox1/iron/Kdm6b signaling axis incurs anti-tumor immunity and tumor suppression. Collectively, we report an iron-loaded FerroCAF cluster that drives immunosuppression through an iron-dependent epigenetic reprogramming mechanism and reveal promising therapeutic targets to boost anti-tumor immunity.

Double-strand breaks in facultative heterochromatin require specific movements and chromatin changes for efficient repair.

DNA double-strand breaks (DSBs) must be properly repaired within diverse chromatin domains to maintain genome stability. Whereas euchromatin has an open structure and is associated with transcription, facultative heterochromatin is essential to silence developmental genes and forms compact nuclear condensates, called polycomb bodies. Whether the specific chromatin properties of facultative heterochromatin require distinct DSB repair mechanisms remains unknown. Here, we integrate single DSB systems in euchromatin and facultative heterochromatin in Drosophila melanogaster and find that heterochromatic DSBs rapidly move outside polycomb bodies. These DSB movements coincide with a break-proximal reduction in the canonical heterochromatin mark histone H3 Lysine 27 trimethylation (H3K27me3). We demonstrate that DSB movement and loss of H3K27me3 at heterochromatic DSBs depend on the histone demethylase dUtx. Moreover, loss of dUtx specifically disrupts completion of homologous recombination at heterochromatic DSBs. We conclude that DSBs in facultative heterochromatin require dUtx-mediated loss of H3K27me3 to promote DSB movement and repair.

Epigenetic therapies targeting histone lysine methylation: complex mechanisms and clinical challenges.

As epigenetic therapies continue to gain ground as potential treatment strategies for cancer and other diseases, compounds that target histone lysine methylation and the enzyme complexes represent a major frontier for therapeutic development. Clinically viable therapies targeting the activities of histone lysine methyltransferases (HKMT) and demethylases (HKDMs) have only recently begun to emerge following FDA approval of the EZH2 inhibitor tazemetostat in 2020 and remain limited to compounds targeting the well-studied SET domain-containing HKMTs and their opposing HKDMs. These include the H3K27 methyltransferases EZH2/EZH1, the singular H3K79 methyltransferase DOT1L, and the H3K4 methyltransferase MLL1/COMPASS as well as H3K9 and H3K36 methyltransferases. They additionally include the H3K4/9-preferential demethylase LSD1 and the H3K4-, H3K27-, and H3K36-preferential KDM5, KDM6, and KDM2 demethylase subfamilies, respectively. This Review discusses the results of recent clinical and preclinical studies relevant to all of these existing and potential therapies. It provides an update on advancements in therapeutic development, as well as more basic molecular understanding, within the past 5 years approximately. It also offers a perspective on histone lysine methylation that departs from the long-predominant "histone code" metaphor, emphasizing complex-disrupting inhibitors and proximity-based approaches rather than catalytic domain inhibitors in the outlook for future therapeutic development.

Histone demethylase PHF8 protected against chondrocyte injury and alleviated posttraumatic osteoarthritis by epigenetically enhancing WWP2 expression.

Aberrant mechanical forces were considered as an important factor for osteoarthritis (OA) pathogenesis. Plant homeodomain finger-containing protein 8 (PHF8) participated in osteogenic differentiation and inflammatory progression. However, the role of PHF8 in aberrant force-related OA remains to be elucidated. In this study, a fluid shear stress (FSS) model in ATDC5 cells and an anterior cruciate ligament transection (ACLT) animal model were constructed. The results revealed the decrease of PHF8 in aberrant force-induced cartilage damage in vitro and in vivo. PHF8 overexpression alleviated the aberrant force-induced cell apoptosis, extracellular matrix degradation, and inflammation. Chromatin immunoprecipitation (ChIP) assays demonstrated that PHF8 epigenetically regulated WWP2 expression through demethylating H3K9me2 at WWP2 promoter, which was influenced by FSS treatment. C-X-C chemokine receptor type 4 (CXCR4) was identified as a potential substrate of WWP2. Co-immunoprecipitation (Co-IP) and ubiquitination experiments further demonstrated WWP2 decreased the stability of CXCR4 via the ubiquitination pathway. Subsequently, rescue experiments validated reintroduction of WWP2 significantly attenuated the effects of PHF8 deletion on FSS-induced chondrocyte injury, and CXCR4 overexpression reversed the protective effects of WWP2 overexpression on chondrocyte injury in FSS-treated ATDC5 cells. Moreover, delivery of a PHF8 adeno-associated virus (AAV) into articular cartilage remarkably ameliorated the breakdown of cartilage matrix by ACLT in mice. In conclusion, our findings highlighted the importance of PHF8/WWP2/CXCR4 signaling pathway in aberrant force-induced cartilage injury, which might provide a novel insight on future epigenetic-based treatment of posttraumatic OA.

Role and mechanism of histone demethylase PHF8 in weightlessness osteoporosis.

Weightlessness osteoporosis, which progresses continuously and has limited protective effects, has become one of the major problems that need to be solved in manned spaceflight. Our study aims to investigate the regulatory role of PHF8 in disuse osteoporosis by observing the expression of PHF8 in bone marrow mesenchymal stem cells (BMSCs) under simulated weightlessness conditions. Therefore, we used the model of ground-based microgravity simulated by disuse osteoporosis patients and tail suspension in mice to simulate microgravity in vivo, and measured the expression of PHF8 in bone tissue. Subsequently, we used the 2D gyroscope to simulate the weightless effect on bone marrow mesenchymal stem cells. In the weightless condition, we detected the proliferation, apoptosis, osteogenesis, and osteogenic differentiation functions of BMSCs. We also detected the expression of osteogenic-related transcription factors after knocking down and overexpressing PHF8. Our results show that the weightless effect can inhibit the proliferation, osteogenesis, and osteogenic differentiation functions of BMSCs, while enhancing their apoptosis; and overexpression of PHF8 can partially alleviate the osteoporosis caused by simulated weightlessness, providing new ideas and clues for potential drug targets to prevent weightlessness and disuse osteoporosis.

USP1-mediated deubiquitination of KDM1A promotes the malignant progression of triple-negative breast cancer.

Previous research has indicated the highly expressed lysine-specific histone demethylase 1A (KDM1A) in several human malignancies, including triple-negative breast cancer (TNBC). However, its detailed mechanisms in TNBC development remain poorly understood. The mRNA levels of KDM1A and Yin Yang 1 (YY1) were determined by RT-qPCR analysis. Western blot was performed to measure KDM1A and ubiquitin-specific protease 1 (USP1) protein expression. Cell proliferation, apoptosis, invasion, migration and stemness were evaluated by MTT assay, EdU assay, flow cytometry, transwell invasion assay, wound-healing assay and sphere-formation assay, respectively. ChIP and dual-luciferase reporter assays were conducted to determine the relationship between YY1 and KDM1A. Xenograft tumor experiment and IHC were carried out to investigate the roles of USP1 and KDM1A in TNBC development in vivo. The highly expressed KDM1A was demonstrated in TNBC tissues and cells, and KDM1A knockdown significantly promoted cell apoptosis, and hampered cell proliferation, invasion, migration, and stemness in TNBC cells. USP1 could increase the stability of KDM1A via deubiquitination, and USP1 depletion restrained the progression of TNBC cells through decreasing KDM1A expression. Moreover, YY1 transcriptionally activated KDM1A expression by directly binding to its promoter in TNBC cells. Additionally, USP1 inhibition reduced KDM1A expression to suppress tumor growth in TNBC mice in vivo. In conclusion, YY1 upregulation increased KDM1A expression via transcriptional activation. USP1 stabilized KDM1A through deubiquitination to promote TNBC progression.

Wnt-deficient and hypoxic environment orchestrates squamous reprogramming of human pancreatic ductal adenocarcinoma.

Human pancreatic cancer is characterized by the molecular diversity encompassing native duct-like and squamous cell-like identities, but mechanisms underlying squamous transdifferentiation have remained elusive. To comprehensively capture the molecular diversity of human pancreatic cancer, we here profiled 65 patient-derived pancreatic cancer organoid lines, including six adenosquamous carcinoma lines. H3K27me3-mediated erasure of the ductal lineage specifiers and hijacking of the TP63-driven squamous-cell programme drove squamous-cell commitment, providing survival benefit in a Wnt-deficient environment and hypoxic conditions. Gene engineering of normal pancreatic duct organoids revealed that GATA6 loss and a Wnt-deficient environment, in concert with genetic or hypoxia-mediated inactivation of KDM6A, facilitate squamous reprogramming, which in turn enhances environmental fitness. EZH2 inhibition counterbalanced the epigenetic bias and curbed the growth of adenosquamous cancer organoids. Our results demonstrate how an adversarial microenvironment dictates the molecular and histological evolution of human pancreatic cancer and provide insights into the principles and significance of lineage conversion in human cancer.

The scaffolding function of LSD1 controls DNA methylation in mouse ESCs.

Lysine-specific histone demethylase 1 (LSD1), which demethylates mono- or di- methylated histone H3 on lysine 4 (H3K4me1/2), is essential for early embryogenesis and development. Here we show that LSD1 is dispensable for mouse embryonic stem cell (ESC) self-renewal but is required for mouse ESC growth and differentiation. Reintroduction of a catalytically-impaired LSD1 (LSD1MUT) recovers the proliferation capability of mouse ESCs, yet the enzymatic activity of LSD1 is essential to ensure proper differentiation. Indeed, increased H3K4me1 in Lsd1 knockout (KO) mouse ESCs does not lead to major changes in global gene expression programs related to stemness. However, ablation of LSD1 but not LSD1MUT results in decreased DNMT1 and UHRF1 proteins coupled to global hypomethylation. We show that both LSD1 and LSD1MUT control protein stability of UHRF1 and DNMT1 through interaction with HDAC1 and the ubiquitin-specific peptidase 7 (USP7), consequently, facilitating the deacetylation and deubiquitination of DNMT1 and UHRF1. Our studies elucidate a mechanism by which LSD1 controls DNA methylation in mouse ESCs, independently of its lysine demethylase activity.

Homocysteine metabolites impair the PHF8/H4K20me1/mTOR/autophagy pathway by upregulating the expression of histone demethylase PHF8-targeting microRNAs in human vascular endothelial cells and mice.

The inability to efficiently metabolize homocysteine (Hcy) due to nutritional and genetic deficiencies, leads to hyperhomocysteinemia (HHcy) and endothelial dysfunction, a hallmark of atherosclerosis which underpins cardiovascular disease (CVD). PHF8 is a histone demethylase that demethylates H4K20me1, which affects the mammalian target of rapamycin (mTOR) signaling and autophagy, processes that play important roles in CVD. PHF8 is regulated by microRNA (miR) such as miR-22-3p and miR-1229-3p. Biochemically, HHcy is characterized by elevated levels of Hcy, Hcy-thiolactone and N-Hcy-protein. Here, we examined the effects of these metabolites on miR-22-3p, miR-1229-3p, and their target PHF8, as well as on the downstream consequences of these effects on H4K20me1, mTOR-, and autophagy-related proteins and mRNAs expression in human umbilical vein endothelial cells (HUVEC). We found that treatments with N-Hcy-protein, Hcy-thiolactone, or Hcy upregulated miR-22-3p and miR-1229-3p, attenuated PHF8 expression, upregulated H4K20me1, mTOR, and phospho-mTOR. Autophagy-related proteins (BECN1, ATG5, ATG7, lipidated LC3-II, and LC3-II/LC3-I ratio) were significantly downregulated by at least one of these metabolites. We also found similar changes in the expression of miR-22-3p, Phf8, mTOR- and autophagy-related proteins/mRNAs in vivo in hearts of Cbs-/- mice, which show severe HHcy and endothelial dysfunction. Treatments with inhibitors of miR-22-3p or miR-1229-3p abrogated the effects of Hcy-thiolactone, N-Hcy-protein, and Hcy on miR expression and on PHF8, H4K20me1, mTOR-, and autophagy-related proteins/mRNAs in HUVEC. Taken together, these findings show that Hcy metabolites upregulate miR-22-3p and miR-1229-3p expression, which then dysregulate the PHF8/H4K20me1/mTOR/autophagy pathway, important for vascular homeostasis.

miR-96-5p expression is sufficient to induce and maintain the senescent cell fate in the absence of stress.

Senescence is a cell fate driven by different types of stress that results in exit from the cell cycle and expression of an inflammatory senescence-associated secretory phenotype (SASP). Here, we demonstrate that stable overexpression of miR-96-5p was sufficient to induce cellular senescence in the absence of genotoxic stress, inducing expression of certain markers of early senescence including SASP factors while repressing markers of deep senescence including LINE-1 and type 1 interferons. Stable miR-96-5p overexpression led to genome-wide changes in heterochromatin followed by epigenetic activation of p16Ink4a, p21Cip1, and SASP expression, induction of a marker of DNA damage, and induction of a transcriptional signature similar to other senescent lung and endothelial cell types. Expression of miR-96-5p significantly increased following senescence induction in culture cells and with aging in tissues from naturally aged and Ercc1-/Δ progeroid mice. Mechanistically, miR-96-5p directly suppressed expression of SIN3B and SIN3 corepressor complex constituents KDM5A and MORF4L2, and siRNA-mediated knockdown of these transcriptional regulators recapitulated the senescent phenotype. In addition, pharmacologic inhibition of the SIN3 complex suppressed senescence and SASP markers. These results clearly demonstrate that a single microRNA is sufficient to drive early senescence in the absence of genotoxic stress through targeting epigenetic and transcriptional regulators, identifying novel targets for the development of senotherapeutics.

Syntheses of LSD1/HDAC Inhibitors with Demonstrated Efficacy against Colorectal Cancer: In Vitro and In Vivo Studies Including Patient-Derived Organoids.

Precedential evidence ascertaining the overexpression of LSD1 and HDACs in colorectal cancer spurred us to design a series of dual LSD1-HDAC inhibitors. Capitalizing on the modular nature of the three-component HDAC inhibitory model, tranylcypromine as a surface recognition motif was appended to zinc-binding motifs via diverse linkers. A compendium of hydroxamic acids was generated and evaluated for in vitro cytotoxicity against HCT-116 cells (human colorectal cancer cell lines). The most potent cell growth inhibitor 2 (GI50 = 0.495 µMm HCT-116 cells) shows promising anticancer effects by reducing colony formation and inducing cell cycle arrest in HCT-116 cells. It exhibits preferential inhibition of HDAC6, along with potent inhibition of LSD1 compared to standard inhibitors. Moreover, Compound 2 upregulates acetyl-tubulin, acetyl-histone H3, and H3K4me2, indicative of LSD1 and HDAC inhibition. In vivo, it demonstrates significant antitumor activity against colorectal cancer, better than irinotecan, and effectively inhibits growth in patient-derived CRC organoids.

Discovery of 2-Aryl-4-aminoquinazolin-Based LSD1 Inhibitors to Activate Immune Response in Gastric Cancer.

LSD1 (histone lysine-specific demethylase 1) has been gradually disclosed to act as an immunomodulator to enhance antitumor immune response. Despite the identification of numerous potent LSD1 inhibitors, there remains a lack of LSD1 inhibitors approved for marketing. Novel LSD1 inhibitors with different mechanisms are therefore needed. Herein, we reported a series of novel quinazoline-based LSD1 inhibitors. Among them, compound Z-1 exhibited the best LSD1 inhibitory activity (IC50 = 0.108 µM). Z-1 also acted as a selective and cellular active as an LSD1 inhibitor. Furthermore, Z-1 promoted response of gastric cancer cells to T-cell killing effect by decreasing PD-L1 expression and further attenuated the PD-1/PD-L1 interaction. In vivo, Z-1 exhibited significant suppression effect on the growth of gastric cancer cells without obvious toxicity. Therefore, Z-1 represents a potential novel immunomodulator that targets LSD1, providing a lead compound with new function mechanism for gastric cancer treatment.

[ORY-1001 inhibits glioblastoma cell growth by downregulating the Notch/HES1 pathway via suppressing lysine-specific demethylase 1 expression].

OBJECTIVE: To explore the inhibitory effect ORY-1001, a lysine-specific histone demethylase 1 (LSD1) inhibitor, on growth of glioblastoma (GBM) and the underlying mechanism. METHODS: We analyzed LSD1 expressions in GBM and normal brain tissues based on data from TCGA and HPA databases. Female BALB/c mouse models bearing xenografts derived from U87 cells or cells with lentivirus-mediated LSD1 silencing or Notch overexpression were treated with saline or 400 µg/kg ORY-1001 by gavage every 7 days, and GBM formation and survival time of the mice were recorded. The effect of ORY-1001 on GBM cell viability was assessed, and its effect on LSD1 expression was analyzed with Western blotting. The genes and pathways associated with LSD1 were analyzed using bioinformatics methods. Western blotting and qRT-PCR were used to detect Notch/HES1 pathway expression after LSD1 silencing and ORY-1001 treatment. The impact of ORY-1001 on viability of U87 cells with Notch1 silencing or overexpression was assessed, and the regulatory effects of ORY-1001 on Notch/HES1 pathway were analyzed using chromatin immunoprecipitation assay. RESULTS: A high expression of LSD1 in GBM was negatively correlated with patient survival (P < 0.001). ORY-1001 and LSD1 silencing obviously reduced tumor burden and prolonged the survival time of GBM-bearing mice. ORY-1001 treatment significantly inhibited the viability and dose-dependently decreased LSD1 expression in GBM cells, and such inhibitory effect of ORY-1001 was attenuated by LSD1 silencing. The Notch pathway enriched the differential genes related to LSD1, and Notch/HES1 pathway expression was significantly down-regulated after LSD1 silencing and ORY-1001 treatment. Notch1 overexpression significantly attenuated the anti-tumor effect of ORY-1001 on GBM. Mechanistically, ORY-1001 disrupted the interaction between LSD1 and the Notch pathway target genes including Notch3, HES1 and CR2. CONCLUSION: ORY-1001 down-regulates the Notch/HES1 pathway by inhibiting LSD1 expression to suppress the growth of GBM in mice.

Abnormal Immune Profile in Individuals with Kabuki Syndrome.

OBJECTIVE: To analyze the lymphocyte subsets in individuals with Kabuki syndrome for better characterizing the immunological phenotype of this rare congenital disorder. METHODS: We characterized the immunological profile including B-, T- and natural killer-cell subsets in a series (N = 18) of individuals with Kabuki syndrome. RESULTS: All 18 individuals underwent genetic analysis: 15 had a variant in KMT2D and 3 a variant in KDM6A. Eleven of the 18 individuals (61%) had recurrent infections and 9 (50%) respiratory infections. Three (17%) had autoimmune diseases. On immunological analysis, 6 (33%) had CD4 T-cell lymphopenia, which was preferentially associated with the KMT2D truncating variant (5/9 individuals). Eight of 18 individuals (44%) had a humoral deficiency and eight (44%) had B lymphopenia. We found abnormal distributions of T-cell subsets, especially a frequent decrease in recent thymic emigrant CD4 + naive T-cell count in 13/16 individuals (81%). CONCLUSION: The immunological features of Kabuki syndrome showed variable immune disorders with CD4 + T-cell deficiency in one third of cases, which had not been previously reported. In particular, we found a reduction in recent thymic emigrant naïve CD4 + T-cell count in 13 of 16 individuals, representing a novel finding that had not previously been reported.

LSD1 inhibits the invasion and migration of breast cancer through exosomes.

Metastasis accounts for almost 90% of breast cancer-related fatalities, making it frequent malignancy and the main reason of tumor mortality globally among women. LSD1 is a histone demethylase, which plays an important role in breast cancer. In order to explore the effect of LSD1 on invasion and migration of breast cancer, we treated breast cancer cells with MCF7 and T47D exosomes knocked down by LSD1, and the invasion and migration of breast cancer cells were significantly enhanced. This phenomenon indicates that LSD1 can inhibit the invasion and migration of breast cancer cells. miR-1290 expression was downregulated in LSD1 knockdown MCF7 exosomes. By analyzing the database of miR-1290 target gene NAT1, we verified that miR-1290 could regulate the expression of NAT1. These data provide fresh insights into the biology of breast cancer therapy by demonstrating how the epigenetic factor LSD1 stimulates the breast cancer cells' invasion and migration via controlling exosomal miRNA.