Lysine-specific demethylase 1 expression in zebrafish during the early stages of neuronal development

Lysine-specific demethylase 1 （Lsdl） is associated with transcriptional coregulation via the modulation of histone methylation. The expression pattern and function of zebrafish Lsdl has not, however, been studied. Here, we describe the pattern of zebrafish Lsdl expression during different development stages. In the zebrafish embryo, Isdl mRNA was present during the early cleavage stage, indicating that maternally derived Lsdl protein is involved in embryonic patterning. During embryogenesis from 0 to 48 hours post-fertilization （hpf）, the expression of Isdl mRNA in the embryo was ubiquitous before 12 hpf and then became restricted to the antedor of the embryo （particularly in the brain） from 24 hpf to 72 hpf. Inhibition of Lsdl activity （by exposure to tranylcypromine） or knockdown of Isdl expression （by morpholino antisense oligonucleotide injection） led to the loss of cells in the brain and to a dramatic downregulatJon of neural genes, including gad65, gad75, and reelin, but not hey1. These findings indicate an important role of Lsdl during nervous system development in zebrafish.

Histone methyltransferases and demethylases:regulators in balancing osteogenic and adipogenic differentiation of mesenchymal stem cells

Mesenchymal stem cells （MSCs） are characterized by their self-renewing capacity and differentiation potential into multiple tissues. Thus, management of the differentiation capacities of MSCs is important for MSC-based regenerative medicine, such as craniofacial bone regeneration, and in new treatments for metabolic bone diseases, such as osteoporosis. In recent years, histone modification has been a growing topic in the field of MSC lineage specification, in which the Su（var）3-9, enhancer-of-zeste, trithorax （SET） domain-containing family and the Jumonji C （JmjC） domain-containing family represent the major histone lysine methyltransferases （KMTs） and histone lysine demethylases （KDMs）, respectively. In this review, we summarize the current understanding of the epigenetic mechanisms by which SET domain-containine KMTs and JmiC domain-containinlz KDMs balance the osteogenic and adipogenic differentiation of MSCs.

Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation

Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.

DNA N^6-methyladenine demethylase ALKBH1 enhances osteogenic differentiation of human MSCs

ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine （N6-mA）, a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the role of ALKBH1 and DNA N6-mA in regulating osteogenic differentiation is largely unknown. In this study, we demonstrated that the expression of ALKBH1 in human mesenchymal stem cells （MSCs） was upregulated during osteogenic induction. Knockdown of ALKBH1 increased the genomic DNA N6-mA levels and significantly reduced the expression of osteogenic-related genes, alkaline phosphatase activity, and mineralization. ALKBHl-depleted MSCs also exhibited a restricted capacity for bone formation in vivo. By contrast, the ectopic overexpression of ALKBH1 enhanced osteoblastic differentiation. Mechanically, we found that the depletion of ALKBH1 resulted in the accumulation of N6-mA on the promoter region of ATF4, which subsequently silenced ATF4 transcription. In addition, restoring the expression of ATP by adenovirus-mediated transduction successfully rescued osteogenic differentiation. Taken together, our results demonstrate that ALKBH1 is indispensable for the osteogenic differentiation of MSCs and indicate that DNA N6-mA modifications area new mechanism for the epigenetic regulation of stem cell differentiation.

Phylogenetic diversity of dimethylsulfoniopropionate-dependent demethylase gene dmdA in distantly related bacteria isolated from Arctic and Antarctic marine environments

Dimethylsulfoniopropionate(DMSP) is mainly produced by marine phytoplankton as an osmolyte, antioxidant,predator deterrent, or cryoprotectant. DMSP is also an important carbon and sulfur source for marine bacteria.Bacteria may metabolize DMSP via the demethylation pathway involving the DMSP demethylase gene(dmdA) or the cleavage pathway involving several different DMSP lyase genes. Most DMSP released into seawater is degraded by bacteria via demethylation. To test a hypothesis that the high gene frequency of dmdA among major marine taxa results in part from horizontal gene transfer(HGT) events, a total of thirty-one bacterial strains were isolated from Arctic Kongsfjorden seawater in this study. Analysis of 16S rRNA gene sequences showed that,except for strains BSw22118, BSw22131 and BSw22132 belonging to the genera Colwellia, Pseudomonas and Glaciecola, respectively, all bacteria fell into the genus Pseudoalteromonas. DmdA genes were detected in five distantly related bacterial strains, including four Arctic strains(Pseudoalteromonas sp. BSw22112, Colwellia sp.BSw22118, Pseudomonas sp. BSw22131 and Glaciecola sp. BSw22132) and one Antarctic strain(Roseicitreum antarcticum ZS2–28). Their dmdA genes showed significant similarities(97.7%–98.3%) to that of Ruegeria pomeroyi DSS–3, which was originally isolated from temperate coastal seawater. In addition, the sequence of the gene transfer agent(GTA) capsid protein gene(g5) detected in Antarctic strain ZS2–28 exhibited a genetically closely related to that of Ruegeria pomeroyi DSS–3. Among the five tested strains, only Pseudomonas sp. BSw22131 could grow using DMSP as the sole carbon source. The results of this study support the hypothesis of HGT for dmdA among taxonomically heterogeneous bacterioplankton, and suggest a wide distribution of functional gene(i.e., dmdA) in global marine environments.

Mitochondrial pathway of the lysine demethylase 5C inhibitor CPI-455 in the Eca-109 esophageal squamous cell carcinoma cell line

BACKGROUND Esophageal cancer is a malignant tumor of the digestive tract that is difficult to diagnose early.CPI-455 has been reported to inhibit various cancers,but its role in esophageal squamous cell carcinoma(ESCC)is unknown.AIM To investigate the effects and mechanism of the lysine demethylase 5C inhibitor,CPI-455,on ESCC cells.METHODS A methyl tetrazolium assay was used to detect the inhibitory effect of CPI-455 on the proliferation of Eca-109 cells.Apoptosis,reactive oxygen species(ROS),and mitochondrial membrane potential were assessed by flow cytometry.Laser confocal scanning and transmission electron microscopy were used to observe changes in Eca-109 cell morphology.The protein expression of P53,Bax,lysinespecific demethylase 5C(KDM5C),cleaved Caspase-9,and cleaved Caspase-3 were assayed by western blotting.RESULTS Compared with the control group,CPI-455 significantly inhibited Eca-109 cell proliferation.Gemcitabine inhibited Eca-109 cell proliferation in a concentrationand time-dependent manner.CPI-455 caused extensive alteration of the mitochondria,which appeared to have become atrophied.The cell membrane was weakly stained and the cytoplasmic structures were indistinct and disorganized,with serious cavitation when viewed by transmission electron microscopy.The flow cytometry and western blot results showed that,compared with the control group,the mitochondrial membrane potential was decreased and depolarized in Eca-109 cells treated with CPI-455.CPI-455 significantly upregulated the ROS content,P53,Bax,Caspase-9,and Caspase-3 protein expression in Eca-109 cells,whereas KDM5C expression was downregulated.CONCLUSION CPI-455 inhibited Eca-109 cell proliferation via mitochondrial apoptosis by regulating the expression of related genes.

Genome-wide identification and expression analysis of DNA demethylase family in cotton

Background:DNA methylation is an important epigenetic factor that maintains and regulates gene expression.The mode and level of DNA methylation depend on the roles of DNA methyltransferase and demethylase,while DNA demethylase plays a key role in the process of DNA demethylation.The results showed that the plant’s DNA demethylase all contained conserved DNA glycosidase domain.This study identified the cotton DNA demethylase gene family and analyzed it using bioinformatics methods to lay the foundation for further study of cotton demethylase gene function.Results:This study used genomic information from diploid Gossypium raimondii JGI(D),Gossypium arboreum L.CRI(A),Gossypium hirsutum L.JGI(AD1) and Gossypium barbadebse L NAU(AD2) to Arabidopsis thaliana.Using DNA demethylase genes sequence of Arabidopsis as reference,25 DNA demethylase genes were identified in cotton by BLAST analysis.There are 4 genes in the genome D,5 genes in the genome A,10 genes in the genome AD1,and 6 genes in the genome AD2.The gene structure and evolution were analyzed by bioinformatics,and the expression patterns of DNA demethylase gene family in Gossypium hirsutum L were analyzed.From the phylogenetic tree analysis,the DNA demethylase gene family of cotton can be divided into four subfamilies:REPRESSOR of SILENCING 1(ROS1),DEMETER(DME),DEMETER-LIKE 2(DML2),and DEMETER-LIKE3(DML3).The sequence similarity of DNA demethylase genes in the same species was higher,and the genetic relationship was also relatively close.Analysis of the gene structure revealed that the DNA demethylase gene family members of the four subfamilies varied greatly.Among them,the number of introns of ROS1 and DME subfamily was larger,and the gene structure was more complex.For the analysis of the conserved domain,it was known that the DNA demethylase family gene member has an endonuclease Ⅲ(END03 c) domain.Conclusion:The genes of the DNA demethylase family are distributed differently in different cotton species,and the gene structure is very different.High expression of ROS1 genes in cotton were under abiotic stress.The expression levels of ROS1 genes were higher during the formation of cotton ovule.The transcription levels of ROS1 family genes were higher during cotton fiber development.

Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1

Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected potential regulatory mechanisms underlying OA and have concentrated on developing novel treatment strategies,the epigenetic control of OA remains unclear.Histone demethylase JMJD3 has been reported to mediate multiple physiological and pathological processes,including cell differentiation,proliferation,autophagy,and apoptosis.However,the regulation of JMJD3 in aberrant force-related OA and its mediatory effect on disease progression are still unknown.In this work,we confirmed the upregulation of JMJD3 in aberrant forceinduced cartilage injury in vitro and in vivo.Functionally,inhibition of JMJD3 by its inhibitor,GSK-J4,or downregulation of JMJD3 by adenovirus infection of sh-JMJD3 could alleviate the aberrant force-induced chondrocyte injury.Mechanistic investigation illustrated that aberrant force induces JMJD3 expression and then demethylates H3K27me3 at the NR4A1 promoter to promote its expression.Further experiments indicated that NR4A1 can regulate chondrocyte apoptosis,cartilage degeneration,extracellular matrix degradation,and inflammatory responses.In vivo,anterior cruciate ligament transection(ACLT)was performed to construct an OA model,and the therapeutic effect of GSK-J4 was validated.More importantly,we adopted a peptide-si RNA nanoplatform to deliver si-JMJD3 into articular cartilage,and the severity of joint degeneration was remarkably mitigated.Taken together,our findings demonstrated that JMJD3 is flow-responsive and epigenetically regulates OA progression.Our work provides evidences for JMJD3 inhibition as an innovative epigenetic therapy approach for joint diseases by utilizing p5RHH-si RNA nanocomplexes.

Modulation of cell death pathways in cancer stem cells: Targeting histone demethylases

Cancer stem cells (CSCs) are tumor initiating cells within the tumor mass;that play a critical role in cancer pathogenesis. CSCs regulate cancer cell survival, metastatic potential, resistance to conventional radio-chemotherapy, disease relapse and poor prognosis. Recent studies have established that the drug resistant cancers and cancer cell lines possess high stem cell like traits compared to their drug sensitive counterparts. Histone demethylases are recently been linked to drug induced reversible tolerant state in cancers. Lysine histone demethylases are enzymes those demethylate lysines in histones and can act as transcriptional repressors or activators. Apart from histones other cellular proteins like E2F1, Rb, STAT3 and p53 are also regulated by methylation and demethylation cycles. In cancer cells these enzymes regulate cell survival, migration, invasion, and proliferation. This review summarizes the current progress of research on the role of histone demethylases in supporting drug tolerant cancer stem cell state and their potential as a drug target.

Demethylase-assisted site-specific detection of N^(1)-methyladenosine in RNA

The dynamic RNA modifications have been viewed as new posttranscriptional regulator in modulating gene expression as well as in a broad range of physiological processes.N^(1)-methyladenosine(m^(1)A)is one of the most prevalent modifications existing in multiple types of RNAs.In-depth investigation of the functions of m^(1)A requires the site-specific assessment of m^(1)A stoichiometry in RNA.Herein,we established a demethylase-assisted method(DA-m^(1)A)for the site-specific detection and quantification of m^(1)A in RNA.N^(1)-methyl group in m^(1)A could result in the stalling of reverse transcription at m^(1)A site,thus producing the truncated cDNA.E.coli AlkB is a demethylase that can demethylate m^(1)A to produce adenine in RNA,thus generating full-length cDNA from AlkB-treated RNA.Evaluation of the produced amounts of full-length cDNA by quantitative real-time PCR can achieve the site-specific detection and quantification of m^(1)A in RNA.With the DA-m^(1)A method,we examined and successfully confirmed the previously well-characterized m^(1)A sites in various types of RNAs with low false positive rate.In addition,we found that the level of m^(1)A was significantly decreased at the bromodomain containing 2(BRD2)mRNA position 1674 and CST telomere replication complex component 1(CTC1)mRNA position 5643 in human hepatocellular carcinoma tissues.The results suggest that these two m^(1)A sites in mRNA may be involved in liver tumorigenesis.Taken together,the DA-m^(1)A method is simple and enables the rapid,cost-effective,and site-specific detection and quantification of m^(1)A in RNA,which provides a valuable tool to decipher the functions of m^(1)A in human diseases.

The GATA transcription factor TaGATA1 recruits demethylase TaELF6-A1 and enhances seed dormancy in wheat by directly regulating TaABI5

Seed dormancy is an important agronomic trait in crops, and plants with low dormancy are prone to preharvest sprouting(PHS) under high-temperature and humid conditions. In this study,we report that the GATA transcription factor TaGATA1 is a positive regulator of seed dormancy by regulating TaABI5 expression in wheat.Our results demonstrate that TaGATA1 overexpression significantly enhances seed dormancy and increases resistance to PHS in wheat. Gene expression patterns, abscisic acid(ABA) response assay, and transcriptome analysis all indicate that TaGATA1 functions through the ABA signaling pathway. The transcript abundance of TaABI5, an essential regulator in the ABA signaling pathway,is significantly elevated in plants overexpressing TaGATA1. Chromatin immunoprecipitation assay(ChIP) and transient expression analysis showed that TaGATA1 binds to the GATA motifs at the promoter of TaABI5 and induces its expression.We also demonstrate that TaGATA1 physically interacts with the putative demethylase TaELF6-A1, the wheat orthologue of Arabidopsis ELF6.ChIP–qPCR analysis showed that H3K27me3 levels significantly decline at the TaABI5 promoter in the TaGATA1-overexpression wheat line and that transient expression of TaELF6-A1 reduces methylation levels at the TaABI5 promoter, increasing TaABI5 expression. These findings reveal a new transcription module, including TaGATA1–TaELF6-A1–TaABI5, which contributes to seed dormancy through the ABA signaling pathway and epigenetic reprogramming at the target site. TaGATA1 could be a candidate gene for improving PHS resistance.

Molecular evolutionary analysis of gene families encoding DNA recombination and repair proteins and histone demethylases,and their functional implications

Many eukaryotic genes are members of multi-gene families due to gene duplications, which generate new copies that allow functional divergence. However, the relationship between

Comparative Analysis of JmjC Domain-containing Proteins Reveals the Potential Histone Demethylases in Arabidopsis and Rice

Histone methylation homeostasis is achieved by controlling the balance between methylation and demethylation to maintain chromatin function and developmental regulation. In animals, a conserved Jumonji C （JmjC） domain was found in a large group of histone demethylases. However, it is still unclear whether plants also contain the JmjC domain- containing active histone demethylases. Here we performed genome-wide screen and phylogenetic analysis of JmjC domain-containing proteins in the dicot plant, Arabidopsis, and monocot plant rice, and found 21 and 20 JmjC domain-containing, respectively. We also examined the expression of JmjC domain-containing proteins and compared them to human JmjC counterparts for potential enzymatic activity. The spatial expression patterns of the Arabidopsis JmjC domain-containing genes revealed that they are all actively transcribed genes. These active plant JmjC domain-containing genes could possibly function in epigenetic regulation to antagonize the activity of the large number of putative SET domain-containing histone methyltransferase activity to dynamically regulate histone methylation homeostasis.

Development of the triazole-fused pyrimidine derivatives as highly potent and reversible inhibitors of histone lysine specific demethylase1(LSD1/KDM1A)

Histone lysine specific demethylase 1(LSD1) has been recognized as an important modulator in post-translational process in epigenetics. Dysregulation of LSD1 has been implicated in the development of various cancers. Herein, we report the discovery of the hit compound 8 a(IC50=3.93 μmol/L) and further medicinal chemistry efforts, leading to the generation of compound 15 u(IC50=49 nmol/L, and Ki= 16 nmol/L), which inhibited LSD1 reversibly and competitively with H3 K4 me2, and was selective to LSD1 over MAO-A/B. Docking studies were performed to rationalize the potency ofcompound 15 u. Compound 15 u also showed strong antiproliferative activity against four leukemia cell lines(OCL-AML3, K562, THP-1 and U937) as well as the lymphoma cell line Raji with the IC50 values of 1.79, 1.30, 0.45, 1.22 and 1.40 μmol/L, respectively. In THP-1 cell line, 15 u significantly inhibited colony formation and caused remarkable morphological changes. Compound 15 u induced expression of CD86 and CD11 b in THP-1 cells, confirming its cellular activity and ability of inducing differentiation.The findings further indicate that targeting LSD1 is a promising strategy for AML treatment, the triazolefused pyrimidine derivatives are new scaffolds for the development of LSD1/KDM1 A inhibitors.

The RNA N^(6)-methyladenosine demethylase ALKBH9B modulates ABA responses in Arabidopsis

The mRNA modification N^(6)-methyladenosine(m^(6)A)plays vital roles in plant development and biotic and abiotic stress responses.The RNA m^(6)A demethylase ALKBH9 B can remove m^(6)A in alfalfa mosaic virus RNA and plays roles in alfalfa mosaic virus infection in Arabidopsis.However,it is unknown whether ALKBH9 B also exhibits demethylation activity and has a biological role in endogenous plant mRNA.We demonstrated here that mRNA m^(6)A modification is induced by the phytohormone abscisic acid(ABA)and that ALKBH9 B has m^(6)A demethylation activity on endogenous mRNA.Knocking out ALKBH9 B led to hypersensitivity to ABA treatment during seed germination and early seedling development.We further showed that ALKBH9 B removes the m^(6)A modification in the ABA INSENSITIVE 1(ABI1)and BRI1-EMS-SUPPRESSOR 1(BES1)transcripts following ABA treatment,affecting the stability of these mRNAs.Furthermore,we determined that ALKBH9 B acts genetically upstream of the transcription factors ABI3 and ABI5,and its regulatory function in ABA responses depended on ABI3 and ABI5.Our findings reveal the important roles of the m^(6)A modification in ABA responses and highlight the role of ALKBH9 Bmediated m^(6)A demethylation in regulating ABA responses post-transcriptionally.

Small-molecule targeting of oncogenic FTO demethylase in acute myeloid leukemia

With the support of the National Natural Science Foundation of China and the Chinese Academy of Sciences,the laboratory led by Yang CaiGuang(杨财广)from Shanghai Institute of Materia Medica,Chinese Academy of Sciences,has identified a potential therapeutic small molecule for treating the acute myeloid leukemia(AML)by targeting the oncogenic RNA demethylase FTO,which was published in Figure Schematic diagram of small-molecular targeting of the oncogenic FTO demethylase.Cancer Cell(2019,35:677—691).

Promising natural lysine specific demethylase 1 inhibitors for cancer treatment:advances and outlooks

Lysine specific demethylase 1(LSD1),a transcriptional corepressor or coactivator that serves as a demethylase of histone 3 lysine 4 and 9,has become a potential therapeutic target for cancer therapy.LSD1 mediates many cellular signaling pathways and regulates cancer cell proliferation,invasion,migration,and differentiation.Recent research has focused on the exploration of its pharmacological inhibitors.Natural products are a major source of compounds with abundant scaffold diversity and structural complexity,which have made a major contribution to drug discovery,particularly anticancer agents.In this review,we briefly highlight recent advances in natural LSD1 inhibitors over the past decade.We present a comprehensive review on their discovery and identification process,natural plant sources,chemical structures,anticancer effects,and structure-activity relationships,and finally provide our perspective on the development of novel natural LSD1 inhibitors for cancer therapy.

Crystallization and Preliminary Crystallographic Analysis of Histone Demethylase PHF8

The reversible process of histone methylation and demethylation plays important roles of epigenetic regulation1. For example, Truncating mutations in human PHF8 gene

Targeting histone lysine-specific demethylase KDM1A/LSD1 to control epithelial-mesenchymal transition program in breast cancers

Epithelial-mesenchymal transition (EMT) is a plastic and reversible process, essential for development and tissue homeostasis. Under pathological conditions, EMT causes induction of tumor growth, angiogenesis and metastasis. According to its reversible nature, the EMT program is associated with vast epigenetic changes. Targeting the epigenetic network that controls the EMT pathway in disease progression is a novel promising strategy to fight cancer metastasis. The impact of alterations in histone methylation in cancer has led to the identification of histone methyltransferases and demethylases as promising novel targets for therapy. Specifically, the lysine specific demethylase 1 (LSD1, also known as KDM1A) plays a pivotal role in the regulation of EMT. Here we present an overview of the causative role of LSD1 in the EMT process, summarizing recent findings on its emerging functions in cell migration and invasion in breast cancer.

shRNA-interfering LSD1 inhibits proliferation and invasion of gastric cancer cells via VEGF-C/PI3K/AKT signaling pathway

BACKGROUND Histone Lysine Specific Demethylase 1(LSD1)is the first histone demethylase to be discovered,which regulates various biological functions by making lysine of histone H3K4,H3K9 and non-histone substrates demethylated.Abnormal regulation of LSD1 is closely related to the occurrence and development of gastric cancer.The change of LSD1 expression level plays an important role in the proliferation and metastasis of gastric cancer cells.The study of its function and mechanism may provide a theoretical basis for early diagnosis and targeted therapy of gastric cancer.AIM To investigate the effect of downregulation of lysine-specific demethylase 1(LSD1)expression on proliferation and invasion of gastric cancer cells and the possible regulatory mechanisms of the VEGF-C/PI3K/AKT signaling pathway.METHODS The LSD1-specific short hairpin RNA(shRNA)interference plasmid was transiently transfected,and expression of LSD1 was downregulated.The cell proliferation ability of LSD1 was observed by CCK-8 assay after downregulating expression of LSD1.Transwell invasion assay was used to observe the change of cell invasion ability after downregulating expression of LSD1.Expression of phosphorylated phosphoinositide 3-kinase(p-PI3K),PI3K,p-AKT,AKT,vascular endothelial growth factor receptor(VEGFR)-3,matrix metalloproteinase(MMP)-2 and MMP-9 in each group was detected by Western blotting.RESULTS The cell proliferation ability of transiently transfected LSD1-shRNA interference plasmid group was significantly lower than that of the control group(P<0.05).Transwell invasion assay showed that the number of cells across the membrane of the LSD1-shRNA transfection group(238.451±5.216)was significantly lower than that of the control group(49.268±6.984)(P<0.01).Western blotting showed that expression level of VEGF-C,p-PI3K,PI3K,p-AKT,AKT,VEGFR-3,MMP-2 and MMP-9 in the LSD1-shRNA group was significantly lower than that in the control group(P<0.05).CONCLUSION Downregulation of LSD1 expression inhibits metastatic potential of gastric cancer cells,and VEGF-C-mediated activation of PI3K/AKT signaling pathway,which may be an important mechanism for inhibiting lymph node metastasis in gastric cancer cells.