LSD1 Research Articles

Functional Hexafluoroisopropyl Group Used in the Construction of Biologically Important Pyrimidine Derivatives.

A series of versatile 4-((1,1,1,3,3,3-hexafluoropropan-2-yl)oxy)pyridine intermediates have been developed to efficiently produce biaryls, amines, ethers, and thioethers. These hydrolysis-stable ether intermediates exhibit reactivity toward electron-donating groups and nucleophiles in cross-coupling and nucleophilic substitution reactions while surpassing the stability of corresponding aryl halides. In comparison to conventional coupling methods, this protocol offers an alternative pathway for accessing natural product and drug-like compounds without the need for metal catalysts. With assistance of this approach, we successfully obtained a potent P-glycoprotein inhibitor 4k (YS-370), a potent epidermal growth factor receptor inhibitor 4l (YS-363), and a promising lysine-specific demethylase 1 inhibitor 5g.

Fumarate Restrains Alveolar Bone Restoration via Regulating H3K9 Methylation.

Nonresolving inflammation causes irreversible damage to periodontal ligament stem cells (PDLSCs) and impedes alveolar bone restoration. The impaired tissue regeneration ability of stem cells is associated with abnormal mitochondrial metabolism. However, the impact of specific metabolic alterations on the differentiation process of PDLSCs remains to be understood. In this study, we found that inflammation altered the metabolic flux of the tricarboxylic acid cycle and induced the accumulation of fumarate through metabolic testing and metabolic flux analysis. Transcriptome sequencing revealed the potential of fumarate in modulating epigenetics. Specifically, histone methylation typically suppresses the expression of genes related to osteogenesis. Fumarate was found to impede the osteogenic differentiation of PDLSCs that exhibited high levels of H3K9me3. Various techniques, including assay for transposase-accessible chromatin with high-throughput sequencing, chromatin immunoprecipitation sequencing, and RNA sequencing, were used to identify the target genes regulated by H3K9me3. Mechanistically, accumulated fumarate inhibited lysine-specific demethylase 4B (KDM4B) activity and increased H3K9 methylation, thus silencing asporin gene transcription. Preventing fumarate from binding to the histone demethylase KDM4B with α-ketoglutarate effectively restored the impaired osteogenic capacity of PDLSCs and improved alveolar bone recovery. Collectively, our research has revealed the significant impact of accumulated fumarate on the regulation of osteogenesis in stem cells, suggesting that inhibiting fumarate production could be a viable therapeutic approach for treating periodontal diseases.

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-β1 (TGF-β1) - 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.

A Genome-Wide Alternative Splicing Analysis of Gossypium arboreum and Gossypium raimondii During Fiber Development

Alternative splicing (AS) is a crucial post-transcriptional regulatory mechanism that contributes to proteome complexity and versatility in different plant species. However, detailed AS exploration in diploid cotton during fiber development has not been reported. In this study, we comparatively analyzed G. arboreum and G. raimondii AS events during fiber development using transcriptome data and identified 9690 and 7617 AS events that were distributed in 6483 and 4859 genes, respectively. G. arboreum had more AS genes and AS events than G. raimondii, and most AS genes were distributed at both ends of all 13 chromosomes in both diploid cotton species. Four major AS types, including IR, SE, A3SS, and A5SS, were all experimentally validated through RT-PCR assays. G. arboreum and G. raimondii had only 1888 AS genes in common, accounting for one-third and one-half of the total number of AS genes, respectively. Furthermore, we found a lysine-specific demethylase coding gene with a different AS mechanism in G. arboreum and G. raimondii, in which AS isoforms lacked part of a key conserved domain. Our findings may provide new directions for the discovery of functional genes involved in cotton species differentiation.

Application of Machine Learning Methods in Predicting Lysine-specific Histone Demethylase 1 (LSD1) Inhibitors

Background: Lysine-specific histone demethylase 1 (LSD1) is a well-known anti-cancer target for drug discovery. Novel reversible inhibitors of LSD1 are desirable to be developed. Objective: This study aimed to build reliable predictive models to evaluate the antineoplastic efficacy of compounds and reveal the structural foundation underlying the inhibitory activity of LSD1. Methods: Multiple artificial intelligence algorithms were utilized in the development of quantitative structure-activity relationship (QSAR) models. A dataset comprising 915 compounds with welldefined IC50 values against LSD1 was assembled for analysis. The structures of these compounds were described by different descriptor packages. Principal component analysis (PCA) was performed to explore the chemical space distribution of each dataset. Y-randomization test and applicability domain (AD) analysis were deployed to validate the reliability of models. Results: For regression models, a consensus model was constructed by integrating the predictions of four top-performing individual models (SVM_ECFP4, RFR_PyDescriptor, RFR_RDKIT, and TRANSNNI), resulting in enhanced predictive performance as compared to the individual models. The consensus model achieved a determination coefficient (r2, for the test set) value of 0.82. For classification models, the consensus model was derived from the amalgamation of three individual models (ASNN_RDKIT, ASNN_ECFP4, and RFR_ECFP4), and the overall prediction accuracy of the model was 0.96 for external validation. Conclusion: The reliable models could be used to identify highly active LSD1 inhibitors for the purpose of efficient virtual screening. In addition, the important molecular properties and structural fragments derived from this work can provide guidance for the structural optimization of novel LSD1 inhibitors.

KDM1A/LSD1 inhibition enhances chemotherapy response in ovarian cancer.

Ovarian cancer (OCa) is the deadliest of all gynecological cancers. The standard treatment for OCa is platinum-based chemotherapy, such as carboplatin or cisplatin in combination with paclitaxel. Most patients are initially responsive to these treatments; however, nearly 90% will develop recurrence and inevitably succumb to chemotherapy-resistant disease. Recent studies have revealed that the epigenetic modifier lysine-specific histone demethylase 1A (KDM1A/LSD1) is highly overexpressed in OCa. However, the role of KDM1A in chemoresistance and whether its inhibition enhances chemotherapy response in OCa remains uncertain. Analysis of TCGA datasets revealed that KDM1A expression is high in patients who poorly respond to chemotherapy. Western blot analysis show that treatment with chemotherapy drugs cisplatin, carboplatin, and paclitaxel increased KDM1A expression in OCa cells. KDM1A knockdown (KD) or treatment with KDM1A inhibitors NCD38 and SP2509 sensitized established and patient-derived OCa cells to chemotherapy drugs in reducing cell viability and clonogenic survival and inducing apoptosis. Moreover, knockdown of KDM1A sensitized carboplatin-resistant A2780-CP70 cells to carboplatin treatment and paclitaxel-resistant SKOV3-TR cells to paclitaxel. RNA-seq analysis revealed that a combination of KDM1A-KD and cisplatin treatment resulted in the downregulation of genes related to epithelial-mesenchymal transition (EMT). Interestingly, cisplatin treatment increased a subset of NF-κB pathway genes, and KDM1A-KD or KDM1A inhibition reversed this effect. Importantly, KDM1A-KD, in combination with cisplatin, significantly reduced tumor growth compared to a single treatment in an orthotopic intrabursal OCa xenograft model. Collectively, these findings suggest that combination of KDM1A inhibitors with chemotherapy could be a promising therapeutic approach for the treatment of OCa.

Critical Role of Lysine-Specific Histone Demethylase 1 in Kidney Inflammation and Fibrosis

Critical Role of Lysine-Specific Histone Demethylase 1 in Kidney Inflammation and Fibrosis

Lysine-Specific Demethylase 1A Is a Targetable Kidney Disease Causal Gene

Lysine-Specific Demethylase 1A Is a Targetable Kidney Disease Causal Gene

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.

Decreased histone H3K9 dimethylation in synergy with DNA demethylation of Spi-1 binding site contributes to ADAMTS-5 expression in articular cartilage of osteoarthritis mice.

Osteoarthritis (OA) is defined by articular cartilage degeneration, synovial membrane inflammation, and abnormal bone remodeling. Recent study has discovered that OA development is linked to an aberrant epigenetic modification of OA-related genes. Our previous research showed that DNA demethylation in ADAMTS-5 promoter region had a substantial impact on ADAMTS-5 expression in the mouse OA model. This process facilitated the binding of Spi-1 to ADAMTS-5 promoter. While alterations in histone methylation have been documented during embryonic development and cancer development, there is a paucity of data on the change in OA pathogenesis. Even no data have been reported on the role of histone modifications in ADAMTS-5 activation in OA. Following our previous study on the role of DNA methylation, we aimed to examine the contribution of histone H3K9 dimethylation in ADAMTS-5 activation in OA. Additionally, we aimed to elucidate the molecular mechanisms underlying the cooperative interaction between DNA methylation and histone H3K9 dimethylation. The potential for anti-OA intervention therapy which is based on modulating histone H3K9 dimethylation is also explored. We demonstrated that a reduction in histone H3K9 dimethylation, along with DNA demethylation of the Spi-1 binding site, had a role in ADAMTS-5 activation in the articular cartilage of OA mice. Significantly, the conditional deletion of histone demethylase to be identified as lysine-specific demethylase 1 (LSD1) in articular cartilage could alleviate the degenerative features of OA mice. Our study demonstrates the direct impact of histone H3K9 dimethylation on gene expression, which in turn contributes to OA development. This research enhances our understanding of the underlying causes of OA.

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.

KDM4A promotes malignant progression of breast cancer by down-regulating BMP9 inducing consequent enhancement of glutamine metabolism

BackgroundRecent studies have found that histone-modified genes play an increasingly important role in tumor progression. Lysine(K) specific demethylase 4A (KDM4A) is a histone lysine-specific demethylase highly expressed in a variety of malignant tumors, data showed that KDM4A was negatively correlated with the Bone Morphogenetic Protein 9 (BMP9) in breast cancer. And previous experiments have demonstrated that exogenous BMP9 significantly inhibits breast cancer development.Materials and methodsWe detected the expression of KDM4A in breast cancer and the relationship between KDM4A and BMP9 using real-time quantitative PCR (RT-qPCR) and Western blot, and verified the interaction between KDM4A and BMP9 by ChIP experiments. At the same time, we also detected whether KDM4A had effects on the RNA and protein stability of BMP9 using actinomycin D and cycloheximide. Measurement of alpha-ketoglutarate (α-KG) level by ELISA to observe the effect of BMP9 on glutamine metabolism in breast cancer cells. Nucleoplasmic distribution of KDM4A after exogenous BMP9 treatment in breast cancer cells were observed by immunofluorescence staining and Western blot. A subcutaneous xenograft tumor model in nude mice was used to study the therapeutic effects of exogenous BMP9 and KDM4A inhibitor (JIB-04) in breast cancer. CCK-8, conoly formation, Transwell, wound healing, and immunohistochemistry were used to monitor the growth of tumor and cell function.ResultsWe found that KDM4A was abnormally highly expressed in breast cancer, and silenced BMP9 expression by removing histone methyl groups from the BMP9 gene region. Meanwhile, KDM4A could also reduce the stability of BMP9 protein. BMP9 inhibit glutamine metabolism in breast cancer, resulting in a decrease in its product α-KG, is confirmed by ELISA. Altered nucleoplasmic distribution of KDM4A due to decreased α-KG was confirmed by immunofluorescence staining and Western blot. Animal experiments confirm that the combination of exogenous BMP9 and JIB-04 shows significantly better results in breast cancer.ConclusionsKDM4A silences BMP9 expression by removing histone methyl groups from the BMP9 gene region, leading to further enhancement of glutamine metabolism, which contributes to malignant tumor progression. In addition, using JIB-04 in combination with exogenous BMP9 could inhibit the malignant progression of breast cancer cells and the growth of tumors more significantly.

PHF8/KDM7B: A Versatile Histone Demethylase and Epigenetic Modifier in Nervous System Disease and Cancers.

Many human diseases, such as malignant tumors and neurological diseases, have a complex pathophysiological etiology, often accompanied by aberrant epigenetic changes including various histone modifications. Plant homologous domain finger protein 8 (PHF8), also known as lysine-specific demethylase 7B (KDM7B), is a critical histone lysine demethylase (KDM) playing an important role in epigenetic modification. Characterized by the zinc finger plant homology domain (PHD) and the Jumonji C (JmjC) domain, PHF8 preferentially binds to H3K4me3 and erases repressive methyl marks, including H3K9me1/2, H3K27me1, and H4K20me1. PHF8 is indispensable for developmental processes and the loss of PHF8 enzyme activity is linked to neurodevelopmental disorders. Moreover, increasing evidence shows that PHF8 is highly expressed in multiple tumors as an oncogenic factor. These findings indicate that studying the role of PHF8 will facilitate the development of novel therapeutic agents by the manipulation of PHF8 demethylation activity. Herein, we summarize the current knowledge of PHF8 about its structure and demethylation activity and its involvement in development and human diseases, with an emphasis on nervous system disorders and cancer. This review will update our understanding of PHF8 and promote the clinical transformation of its predictive and therapeutic value.

Centromere inactivation during aging can be rescued in human cells.

Aging involves a range of genetic, epigenetic, and physiological alterations. A key characteristic of aged cells is the loss of global heterochromatin, accompanied by a reduction in canonical histone levels. In this study, we track the fate of centromeres during aging in human cells. Our findings reveal that the centromeric histone H3 variant CENP-A is downregulated in aged cells, in a p53-dependent manner. We observe repression of centromeric noncoding transcription through an epigenetic mechanism via recruitment of a lysine-specific demethylase 1 (LSD1/KDM1A) to centromeres. This suppression results in defective de novo CENP-A loading at aging centromeres. By dual inhibition of p53 and LSD1/KDM1A in aged cells, we mitigate the reduction in centromeric proteins and centromeric transcripts, leading to mitotic rejuvenation of these cells. These results offer insights into a novel mechanism for centromeric inactivation during aging and provide potential strategies to reactivate centromeres.

Synthesis of Novel Cu(II), Co(II), Fe(II), and Ni(II) Hydrazone Metal Complexes as Potent Anticancer Agents: Spectroscopic, DFT, Molecular Docking, and MD Simulation Studies.

Metal complexes [FeL], [NiL]·H2O, [CuL], and [CoL]·H2O were formed by the ligand (L, 4-fluoro-N'-(2-hydroxybenzylidene)benzohydrazide) reacting with Fe(OAc)2, Ni(OAc)2·4H2O, Cu(OAc)2·H2O, and Co(OAc)2·4H2O. The produced compounds were characterized using a variety of methods, such as NMR, UV-vis, FT-IR, magnetic susceptibility, elemental analysis, and molar conductivity. The spectrum of the data indicates that the geometry of the complex molecular structures is octahedral with six coordination sites. The ligand and its different metal complexes were tested in a human lung cancer cell line and a normal embryonic kidney cell line. A cytotoxic assay revealed that L-Cu is the most potent chelate against cancer cell lines. A computational study was performed to rationalize this finding. The binding potential of relatively active compounds to a suitable target was analyzed. For this purpose, a target that is known to be inhibited by small compounds with a scaffold similar to that of the synthesized compounds, lysine-specific demethylase 1 (LSD1), was first determined. Molecular docking studies demonstrated that L-Cu has a high binding potential to LSD1 at a level comparable to that of a standard ligand. Molecular dynamics (MD) simulations revealed that L-Cu and L form stable complexes with the enzyme. Furthermore, the MD simulation study showed that L-Cu remained inside the binding pocket of the enzyme during the 200 ns simulation period. Density functional theory (DFT) studies demonstrated that the chemical stability of L was higher than that of its chelate form, L-Cu.

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.

Alpha-ketoglutarate is required for chronic hypoxia-induced cardiac remodeling.

Chronic hypoxia (CH) is commonly associated with various cardiovascular diseases, with cardiac hypertrophy being the most frequently observed alteration. Metabolic remodeling is another consequence seen in the hypoxic heart. However, the mechanistic linkage between metabolic remodeling and cardiac hypertrophy in the hypoxic heart remains unclear. In this study, wild-type C57BL/6J mice were subjected to CH for 4 wk. Echocardiography and morphological analysis were used to assess the cardiac effects. We found that 4 wk of CH led to significant cardiac hypertrophy in the mice, whereas cardiac function remained unchanged compared with normoxic mice. In addition, CH induced an elevation in cardiac alpha-ketoglutarate (α-KG) content. Promoting α-KG degradation in the CH hearts prevented CH-induced cardiac hypertrophy but led to noticeable cardiac dysfunction. Mechanistically, α-KG promoted the transcription of hypertrophy-related genes by regulating histone methylation. Silencing lysine-specific demethylase 5 (KDM5), a histone demethylation enzyme, blunted α-KG-induced transcription of hypertrophy-related genes. These data suggest that α-KG is required for CH-induced cardiac remodeling, thus establishing a connection between metabolic changes and cardiac remodeling in hypoxic hearts.NEW & NOTEWORTHY We reported that alpha-ketoglutarate (α-KG) is indispensable for chronic hypoxia (CH)-induced cardiac remodeling, which builds the bridge between metabolic intermediates and cardiac remodeling.

LSD1 inhibition improves efficacy of adoptive T cell therapy by enhancing CD8+ T cell responsiveness

The lysine-specific histone demethylase 1 A (LSD1) is involved in antitumor immunity; however, its role in shaping CD8 + T cell (CTL) differentiation and function remains largely unexplored. Here, we show that pharmacological inhibition of LSD1 (LSD1i) in CTL in the context of adoptive T cell therapy (ACT) elicits phenotypic and functional alterations, resulting in a robust antitumor immunity in preclinical models in female mice. In addition, the combination of anti-PDL1 treatment with LSD1i-based ACT eradicates the tumor and leads to long-lasting tumor-free survival in a melanoma model, complementing the limited efficacy of the immune or epigenetic therapy alone. Collectively, these results demonstrate that LSD1 modulation improves antitumoral responses generated by ACT and anti-PDL1 therapy, providing the foundation for their clinical evaluation.

Restoration of TFPI2 by LSD1 inhibition suppresses tumor progression and potentiates antitumor immunity in breast cancer

Histone lysine-specific demethylase 1 (LSD1) is frequently overexpressed in triple negative breast cancer (TNBC), which is associated with worse clinical outcome in TNBC patients. However, the underlying mechanisms by which LSD1 promotes TNBC progression remain to be identified. We recently established a genetically engineered murine model by crossing mammary gland conditional LSD1 knockout mice with Brca1-deficient mice to explore the role of LSD1 in TNBC pathogenesis. Cre-mediated Brca1 loss led to higher incidence of tumor formation in mouse mammary glands, which was hindered by concurrent depletion of LSD1, indicating a critical role of LSD1 in promoting Brca1-deficient tumors. We also demonstrated that the silencing of a tumor suppressor gene, Tissue Factor Pathway Inhibitor 2 (TFPI2), is functionally associated with LSD1-mediated TNBC progression. Mouse Brca1-deficient tumors exhibited elevated LSD1 expression and decreased TFPI2 level compared to normal mammary tissues. Analysis of TCGA database revealed that TFPI2 expression is significantly lower in aggressive ER-negative or basal-like BC. Restoration of TFPI2 through LSD1 inhibition increased H3K4me2 enrichment at the TFPI2 promoter, suppressed tumor progression, and enhanced antitumor efficacy of chemotherapeutic agent. Induction of TFPI2 by LSD1 ablation downregulates activity of matrix metalloproteinases (MMPs) that in turn increases the level of cytotoxic T lymphocyte attracting chemokines in tumor environment, leading to enhanced tumor infiltration of CD8+ T cells. Moreover, induction of TFPI2 potentiates antitumor effect of LSD1 inhibitor and immune checkpoint blockade in poorly immunogenic TNBC. Together, our study identifies previously unrecognized roles of TFPI2 in LSD1-mediated TNBC progression, therapeutic response, and immunogenic effects.

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

To explore the inhibitory effect ORY-1001, a lysine-specific histone demethylase 1 (LSD1) inhibitor, on growth of glioblastoma (GBM) and the underlying mechanism. 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. 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. ORY-1001 down-regulates the Notch/HES1 pathway by inhibiting LSD1 expression to suppress the growth of GBM in mice.