ABSTRACT
The treatment for trastuzumab-resistant breast cancer (BC) remains a challenge in clinical settings. It was known that CD47 is preferentially upregulated in HER2+ BC cells, which is correlated with drug resistance to trastuzumab. Here, we developed a novel anti-CD47/HER2 bispecific antibody (BsAb) against trastuzumab-resistant BC, named IMM2902. IMM2902 demonstrated high binding affinity, blocking activity, antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and internalization degradation effects against both trastuzumab-sensitive and trastuzumab-resistant BC cells in vitro. The in vivo experimental data indicated that IMM2902 was more effective than their respective controls in inhibiting tumor growth in a trastuzumab-sensitive BT474 mouse model, a trastuzumab-resistant HCC1954 mouse model, two trastuzumab-resistant patient-derived xenograft (PDX) mouse models and a cord blood (CB)-humanized HCC1954 mouse model. Through spatial transcriptome assays, multiplex immunofluorescence (mIFC) and in vitro assays, our findings provided evidence that IMM2902 effectively stimulates macrophages to generate C-X-C motif chemokine ligand (CXCL) 9 and CXCL10, thereby facilitating the recruitment of T cells and NK cells to the tumor site. Moreover, IMM2902 demonstrated a high safety profile regarding anemia and non-specific cytokines release. Collectively, our results highlighted a novel therapeutic approach for the treatment of HER2+ BCs and this approach exhibits significant anti-tumor efficacy without causing off-target toxicity in trastuzumab-resistant BC cells.
Subject(s)
Antibodies, Bispecific , Breast Neoplasms , CD47 Antigen , Drug Resistance, Neoplasm , Immunotherapy , Receptor, ErbB-2 , Trastuzumab , Xenograft Model Antitumor Assays , Humans , Animals , Trastuzumab/pharmacology , Trastuzumab/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Antibodies, Bispecific/pharmacology , Antibodies, Bispecific/therapeutic use , Female , Drug Resistance, Neoplasm/drug effects , Mice , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-2/immunology , Receptor, ErbB-2/metabolism , CD47 Antigen/antagonists & inhibitors , CD47 Antigen/immunology , Immunotherapy/methods , Antineoplastic Agents, Immunological/pharmacology , Antineoplastic Agents, Immunological/therapeutic use , Cell Line, Tumor , Antibody-Dependent Cell Cytotoxicity/drug effects , Phagocytosis/drug effectsABSTRACT
Lysine-specific demethylase 1 (LSD1) is a flavin adenine dinucleotide (FAD) dependent monoamine oxidase (MAO) that erases the mono-, and dimethylation of histone 3 lysine 4 (H3K4), resulting in the suppression of target gene transcriptions. Besides, it can also demethylate some nonhistone substrates to regulate their biological functions. As reported, LSD1 is widely upregulated and plays a key role in several kinds of cancers, pharmacological or genetic ablation of LSD1 in cancer cells suppresses cell aggressiveness by several distinct mechanisms. Therefore, numerous LSD1 inhibitors, including covalent and noncovalent, have been developed and several of them have entered clinical trials. Herein, we systemically reviewed and discussed the biological function of LSD1 in tumors, lymphocytes as well as LSD1-targeting inhibitors in clinical trials, hoping to benefit the field of LSD1 and its inhibitors.
Subject(s)
Lysine , Neoplasms , Humans , Lysine/therapeutic use , Histone Demethylases/metabolism , Histone Demethylases/therapeutic use , Monoamine Oxidase Inhibitors/therapeutic use , Histones , Neoplasms/drug therapy , Drug Discovery , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic useABSTRACT
Polymerization-induced self-assembly (PISA) is conducted in a non-polar medium (n-dodecane) via reversible complexation-mediated polymerization (RCMP). Stearyl methacrylate (SMA) is used to synthesize a macroinitiator, and subsequent block polymerization of benzyl methacrylate (BzMA) from the macroinitiator in n-dodecane afforded a PSMA-PBzMA block copolymer, where PSMA is poly(stearyl methacrylate) and PBzMA is poly(benzyl methacrylate). Because PSMA is soluble but PBzMA is insoluble in n-dodecane, the block copolymer formed a self-assembly during the block polymerization (PISA). Spherical micelles, worms, and vesicles are obtained, depending on the degrees of polymerization of PSMA and PBzMA. "One-pot" PISA is also attained; namely, BzMA is directly added to the reaction mixture of the macroinitiator synthesis, and PISA is conducted in the same pot without purification of the macroinitiator. The spherical micelle and vesicle structures are also fixed using a crosslinkable monomer during PISA. RCMP-PISA is highly attractive as it is odorless and metal-free. The "one-pot" synthesis does not require the purification of the macroinitiator. RCMP-PISA can provide a practical approach to synthesize self-assemblies in non-polar media.
Subject(s)
Alkanes , Methacrylates , Polymers , Polymethacrylic Acids , Polymerization , Polymers/chemistry , Methacrylates/chemistry , MicellesABSTRACT
With the deepening of the diversification and openness of financial systems, financial vulnerability, as an endogenous attribute of financial systems, becomes an important measurement of financial security. Based on a network analysis, we introduce a network curvature indicator improved by Copula entropy as an innovative metric of financial vulnerability. Compared with the previous network curvature analysis method, the CE-based curvature proposed in this paper can measure market vulnerability and systematic risk with significant advantages.
ABSTRACT
One-pot synthesis of methacrylic and acrylic polymers from benzylic alcohols (R-OH) used as initiating moieties was developed. R-OH was converted to alkyl iodide (R-I), and the generated R-I was used as an initiator without purification or isolation in the subsequent reversible complexation mediated polymerization (RCMP), leading to one-pot RCMP from R-OH. As a useful application, this technique was exploited for one-pot polymer-grafting from lignin that is the second most abundant renewable carbon-source on earth and bears benzylic alcohols. The direct initiation from lignin eliminates tedious initiator attachment and purification, offering a facile access to polymer-grafted lignin. The obtained polymer-grafted lignin was utilized to form an efficient UV-absorbing film with high transparency in visible region. One-pot RCMP may serve as a practical method to obtain value-added functional lignin-polymer composites.
ABSTRACT
SUMMARY: UCSC Xena platform provides huge amounts of processed cancer omics data from large cancer research projects (e.g. TCGA, CCLE and PCAWG) or individual research groups and enables unprecedented research opportunities. However, a graphical user interface-based tool for interactively analyzing UCSC Xena data and generating elegant plots is still lacking, especially for cancer researchers and clinicians with limited programming experience. Here, we present UCSCXenaShiny, an R Shiny package for quickly searching, downloading, exploring, analyzing and visualizing data from UCSC Xena data hubs. This tool could effectively promote the practical use of public data, and can serve as an important complement to the current Xena genomics explorer. AVAILABILITY AND IMPLEMENTATION: UCSCXenaShiny is an open source R package under GPLv3 license and it is freely available at https://github.com/openbiox/UCSCXenaShiny or https://cran.r-project.org/package=UCSCXenaShiny. The docker image is available at https://hub.docker.com/r/shixiangwang/ucscxenashiny. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Subject(s)
Neoplasms , Software , Humans , Genomics , Data Interpretation, StatisticalABSTRACT
Dysregulation of various cells in the tumor microenvironment (TME) causes immunosuppressive functions and aggressive tumor growth. In combination with immune checkpoint blockade (ICB), epigenetic modification-targeted drugs are emerging as attractive cancer treatments. Lysine-specific demethylase 1 (LSD1) is a protein that modifies histone and non-histone proteins and is known to influence a wide variety of physiological processes. The dysfunction of LSD1 contributes to poor prognosis, poor patient survival, drug resistance, immunosuppression, etc., making it a potential epigenetic target for cancer therapy. This review examines how LSD1 modulates different cell behavior in TME and emphasizes the potential use of LSD1 inhibitors in combination with ICB therapy for future cancer research studies.
Subject(s)
Neoplasms , Tumor Microenvironment , Humans , Histones/metabolism , Neoplasms/drug therapy , Epigenesis, Genetic , Histone Demethylases/geneticsABSTRACT
[Figure: see text].
Subject(s)
Heart Failure/metabolism , Histone Demethylases/metabolism , Myofibroblasts/metabolism , Animals , Aortic Valve Stenosis/complications , Cells, Cultured , Heart Failure/etiology , Heart Failure/physiopathology , Histone Demethylases/genetics , Humans , MAP Kinase Signaling System , Mice , Mice, Inbred C57BL , Myocytes, Cardiac/metabolism , Myofibroblasts/pathology , Rats , Rats, Sprague-Dawley , Smad Proteins/metabolism , Transforming Growth Factor beta/metabolism , p38 Mitogen-Activated Protein Kinases/metabolismABSTRACT
Several studies have examined the functions of nucleic acids in small extracellular vesicles (sEVs). However, much less is known about the protein cargos of sEVs and their functions in recipient cells. This study demonstrates the presence of lysine-specific demethylase 1 (LSD1), which is the first identified histone demethylase, in the culture medium of gastric cancer cells. We show that sEVs derived from gastric cancer cells and the plasma of patients with gastric cancer harbor LSD1. The shuttling of LSD1-containing sEVs from donor cells to recipient gastric cancer cells promotes cancer cell stemness by positively regulating the expression of Nanog, OCT4, SOX2, and CD44. Additionally, sEV-delivered LSD1 suppresses oxaliplatin response of recipient cells in vitro and in vivo, whereas LSD1-depleted sEVs do not. Taken together, we demonstrate that LSD1-loaded sEVs can promote stemness and chemoresistance to oxaliplatin. These findings suggest that the LSD1 content of sEV could serve as a biomarker to predict oxaliplatin response in gastric cancer patients.
Subject(s)
Extracellular Vesicles , Stomach Neoplasms , Histone Demethylases/genetics , Humans , Lysine , Stomach Neoplasms/drug therapy , Stomach Neoplasms/geneticsABSTRACT
Cancer immunotherapy is a rapidly developing and effective method for the treatment of a variety of malignancies in recent years. As a significant immune checkpoint, programmed cell death 1 ligand 1 (PD-L1) and its receptor programmed cell death protein 1 (PD-1) play the most significant role in cancer immune escape and cancer immunotherapy. Though PD-L1 have become an important target for drug development and there have been various approved drugs and clinic trials targeting it, and various clinical response rate and adverse reactions prevent many patients from benefiting from it. In recent years, combination trials have become the main direction of PD-1/PD-L1 antibodies development. Here, we summarized PD-L1 biofunctions and key roles in various cancers along with the development of PD-L1 inhibitors. The regulators that are involved in controlling PD-L1 expression including post-translational modification, mRNA level regulation as well as degradation and exosome secretory pathway of PD-L1 were focused. This systematic summary may provide comprehensive understanding of different regulations on PD-L1 as well as a broad prospect for the search of the important regulator of PD-L1. The regulatory factors of PD-L1 can be potential targets for immunotherapy and increase strategies of immunotherapy in combination.
Subject(s)
B7-H1 Antigen , Neoplasms , B7-H1 Antigen/metabolism , Humans , Immunotherapy/methods , Neoplasms/metabolism , Programmed Cell Death 1 Receptor/metabolism , Protein Processing, Post-TranslationalABSTRACT
BACKGROUND: Histone lysine-specific demethylase 1 (LSD1) expression has been shown to be significantly elevated in gastric cancer (GC) and may be associated with the proliferation and metastasis of GC. It has been reported that LSD1 repressed tumor immunity through programmed cell death 1 ligand 1 (PD-L1) in melanoma and breast cancer. The role of LSD1 in the immune microenvironment of GC is unknown. METHODS: Expression LSD1 and PD-L1 in GC patients was analyzed by immunohistochemical (IHC) and Western blotting. Exosomes were isolated from the culture medium of GC cells using an ultracentrifugation method and characterized by transmission electronic microscopy (TEM), nanoparticle tracking analysis (NTA), sucrose gradient centrifugation, and Western blotting. The role of exosomal PD-L1 in T-cell dysfunction was assessed by flow cytometry, T-cell killing and enzyme-linked immunosorbent assay (ELISA). RESULTS: Through in vivo exploration, mouse forestomach carcinoma (MFC) cells with LSD1 knockout (KO) showed significantly slow growth in 615 mice than T-cell-deficient BALB/c nude mice. Meanwhile, in GC specimens, expression of LSD1 was negatively correlated with that of CD8 and positively correlated with that of PD-L1. Further study showed that LSD1 inhibited the response of T cells in the microenvironment of GC by inducing the accumulation of PD-L1 in exosomes, while the membrane PD-L1 stayed constant in GC cells. Using exosomes as vehicles, LSD1 also obstructed T-cell response of other cancer cells while LSD1 deletion rescued T-cell function. It was found that while relying on the existence of LSD1 in donor cells, exosomes can regulate MFC cells proliferation with distinct roles depending on exosomal PD-L1-mediated T-cell immunity in vivo. CONCLUSION: LSD1 deletion decreases exosomal PD-L1 and restores T-cell response in GC; this finding indicates a new mechanism with which LSD1 may regulate cancer immunity in GC and provides a new target for immunotherapy against GC.
Subject(s)
B7-H1 Antigen , Stomach Neoplasms , Animals , Histone Demethylases/genetics , Humans , Mice , Mice, Nude , Stomach Neoplasms/genetics , T-Lymphocytes , Tumor MicroenvironmentABSTRACT
We proposed a novel torsion sensor based on the Lyot filter with the twisted polarization-maintaining fiber (PMF) acting as the birefringence medium. Lyot filter is formed by two linear polarizers and a piece of PMF. Based on the high birefringence of the PMF, the output polarization rotates with a rate equal to the twisting rate applied on the PMF, and the sensor realizes a high sensitivity of 90.072â dB/rad. The proposed sensor also demonstrated a low strain sensitivity of 2.32 ×10 - 6 rad/µÉ. On the other hand, based on the phase hits of the polarization interference, the wavelength sensitivity reaches 15.477â nm/rad. The monitoring range of the wavelength demodulation is complementary with the intensity demodulation in one cycle, making the valid sensing range of the proposed sensor expand. The proposed highly sensitive compact torsion sensor, with large sensing range and low crosstalk, has potential applications in many fields such as manufacturing industry, civil engineering, aerospace industry and modern smart structure monitoring.
ABSTRACT
Mucosa-associated invariant T (MAIT) cells are unconventional innate-like T cells that recognize microbial riboflavin-related metabolites presented by the evolutionarily conserved MHC class I-related (MR1) molecule. MAIT cells are abundant in circulation and mucosal tissues and are poised to mount rapid effector responses against diverse microbial organisms. Despite the absence of virally encoded riboflavin-related metabolite antigens, MAIT cells can respond to viral infections in an MR1-independent and cytokine-dependent manner. In chronic HIV-1 infection, MAIT cells are persistently depleted and functionally exhausted. Long-term effective combination antiretroviral therapy can only partially rescue MAIT cell numbers and dysfunction. Our understanding of the mechanisms underlying MAIT cell loss in HIV-1 infection is still incomplete, and to date, few effective strategies to recover their loss in humans are available. Here, we review current knowledge concerning the mechanisms of MAIT cell responses and loss in different stages of HIV-1 infection and how we may potentially develop strategies to restore these cells in the clinical setting. We further discuss novel strategies that may aid future investigations into MAIT cell immunobiology in HIV-1 infection, including the potential use of three-dimensional organoid models to dissect the mechanisms of MAIT cell depletion and to explore interventions that may restore their numbers and functionality.
ABSTRACT
This work reports the first use of organic chloride salts as catalysts for reversible complexation mediated living radical polymerization. Owing to the strong halogen-bond forming ability of Cl- , the studied four tetraalkylammonium chloride catalysts (R4 N+ Cl- ) successfully control the polymerizations of methyl methacrylate, yielding polymers with low dispersities up to high monomer conversion (>90%). Benzyldodecyldimethylammonium chloride is further exploited to other methacrylates and yields low-dispersity block copolymers. The advantages of the chloride salt catalysts are wide monomer scope, good livingness, accessibility to block copolymers, and good solubility in organic media. Because of the good solubility, the use of the chloride salt catalysts can prevent agglomeration of catalysts on reactor walls in organic media, which is an industrially attractive feature. Among halide anions, chloride anion is the most abundant and least expensive halide anion, and therefore, the use of the chloride salt catalysts may lower the cost of the polymerization.
Subject(s)
Chlorides , Methacrylates , Polymerization , Methacrylates/chemistry , Catalysis , Polymers/chemistry , HalogensABSTRACT
N6-methyladenosine (m6A) is a post-transcriptional RNA modification and one of the most abundant types of RNA chemical modifications. m6A functions as a molecular switch and is involved in a range of biomedical aspects, including cardiovascular diseases, the central nervous system, and cancers. Conceptually, m6A methylation can be dynamically and reversibly modulated by RNA methylation regulatory proteins, resulting in diverse fates of mRNAs. This review focuses on m6A demethylases fat-mass- and obesity-associated protein (FTO) and alkB homolog 5 (ALKBH5), which especially erase m6A modification from target mRNAs. Recent advances have highlighted that FTO and ALKBH5 play an oncogenic role in various cancers, such as acute myeloid leukemias (AML), glioblastoma, and breast cancer. Moreover, studies in vitro and in mouse models confirmed that FTO-specific inhibitors exhibited anti-tumor effects in several cancers. Accumulating evidence has suggested the possibility of FTO and ALKBH5 as therapeutic targets for specific diseases. In this review, we aim to illustrate the structural properties of these two m6A demethylases and the development of their specific inhibitors. Additionally, this review will summarize the biological functions of these two m6A demethylases in various types of cancers and other human diseases.
Subject(s)
Adenosine , Leukemia, Myeloid, Acute , Adenosine/metabolism , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/metabolism , Animals , Humans , Methylation , Mice , RNA/metabolism , RNA, Messenger/metabolismABSTRACT
Bromodomain 4 (BRD4) proteins play an important role in histone post-translational modifications and facilitate several important physiological and pathological processes, including cancers. The inhibition of BRD4 by small molecule inhibitors shows promise as a therapeutic strategy for cancer treatment. However, their clinical applications were limited, which is largely hampered by off-target effects-induced toxicity. We herein report the design, synthesis, and cellular imaging of a set of tumor-anchored and BRD4-targeted fluorescent ligands by introducing selective and potent BRD4 inhibitor into different fluorophores via variable linkers. One of the fluorescent conjugates (compound 6) was demonstrated to be cell-permeable and low cytotoxic, preferentially accumulated in cancer cells, and display pronounced fluorescent signal. More importantly, 6 was identified to show specific BRD4 engagement in the cellular content. Collectively, this study provides a pathway for developing labeled BRD4 ligands and highlights that compound 6 may represent a valuable tool for explorative learning and target delivery study of BRD4.
Subject(s)
Antineoplastic Agents/pharmacology , Cell Cycle Proteins/antagonists & inhibitors , Drug Design , Fluorescent Dyes/pharmacology , Optical Imaging , Transcription Factors/antagonists & inhibitors , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Cycle Proteins/metabolism , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/chemistry , Humans , Ligands , Molecular Docking Simulation , Molecular Structure , Structure-Activity Relationship , Transcription Factors/metabolism , Tumor Cells, CulturedABSTRACT
The ubiquitin-specific protease 7 (USP7)-murine double minute 2 (MDM2)-p53 network plays an important role in the regulation of p53, a tumor suppressor which plays critical roles in regulating cell growth, proliferation, cell cycle progression, apoptosis and immune response. The overexpression of USP7 and MDM2 in human cancers contributes to cancer initiation and progression, and their inhibition reactivates p53 signalings and causes cell cycle arrest and apoptosis. Herein, the current state of pharmacological characterization, potential applications in cancer treatment and mechanism of action of small molecules used to target and inhibit MDM2 and USP7 proteins are highlighted, along with the outcomes in clinical and preclinical settings. Moreover, challenges and advantages of these strategies, as well as perspectives in USP7-MDM2-p53 field are analyzed in detail. The investigation and application of MDM2 and USP7 inhibitors will deepen our understanding of the function of USP7-MDM2-p53 network, and feed in the development of effective and safe cancer therapies where USP7-MDM2-p53 network is implicated.
Subject(s)
Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , Proto-Oncogene Proteins c-mdm2/antagonists & inhibitors , Small Molecule Libraries/pharmacology , Tumor Suppressor Protein p53/antagonists & inhibitors , Ubiquitin-Specific Peptidase 7/antagonists & inhibitors , Antineoplastic Agents/chemistry , Humans , Molecular Structure , Neoplasms/metabolism , Proto-Oncogene Proteins c-mdm2/metabolism , Small Molecule Libraries/chemistry , Tumor Suppressor Protein p53/metabolism , Ubiquitin-Specific Peptidase 7/metabolismABSTRACT
The ubiquitin-proteasome system (UPS) is a complex process that regulates protein stability and activity by the sequential actions of E1, E2 and E3 enzymes to influence diverse aspects of eukaryotic cells. However, due to the diversity of proteins in cells, substrate selection is a highly critical part of the process. As a key player in UPS, E3 ubiquitin ligases recruit substrates for ubiquitination specifically. Among them, RING E3 ubiquitin ligases which are the most abundant E3 ubiquitin ligases contribute to diverse cellular processes. The multisubunit cullin-RING ligases (CRLs) are the largest family of RING E3 ubiquitin ligases with tremendous plasticity in substrate specificity and regulate a vast array of cellular functions. The F-box protein Skp2 is a component of CRL1 (the prototype of CRLs) which is expressed in many tissues and participates in multiple cellular functions such as cell proliferation, metabolism, and tumorigenesis by contributing to the ubiquitination and subsequent degradation of several specific tumor suppressors. Most importantly, Skp2 plays a pivotal role in a plethora of cancer-associated signaling pathways. It enhances cell growth, accelerates cell cycle progression, promotes migration and invasion, and inhibits cell apoptosis among others. Hence, targeting Skp2 may represent a novel and attractive strategy for the treatment of different human cancers overexpressing this oncogene. In this review article, we summarized the known roles of Skp2 both in health and disease states in relation to the UPS.
Subject(s)
Neoplasms , Proteasome Endopeptidase Complex , S-Phase Kinase-Associated Proteins/metabolism , Humans , Proteasome Endopeptidase Complex/metabolism , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism , UbiquitinationABSTRACT
LSD1 (histone lysine specific demethylase 1) takes part in the physiological process of cell differentiation, EMT (epithelial-mesenchymal transition) and immune response. In this study, we found LSD1 expression in metastatic gastric cancer tissues was significantly higher than that in normal tissues. Furthermore, LSD1 deletion was found to suppress gastric cancer migration by decreasing intracellular miR-142-5p, which further led to the upregulation of migration suppressor CD9, a newly identified target of miR-142-5p. While LSD1 was reported as a demethylase of H3K4me1/2, H3K9me1/2 and several non-histone proteins, this is a new evidence for LSD1 as a functional regulator of miRNA. On the other hand, our data suggested that promoting the secretion of miR-142-5p using small extracellular vesicles as vehicles is a new mechanism for LSD1 abrogation to down-regulate intracellular miR-142-5p. Taken together, this study uncovered a new mechanism for LSD1 that can contribute to gastric cancer migration by facilitating miR-142-5p to target CD9.
Subject(s)
Cell Movement , Gene Deletion , Histone Demethylases/metabolism , MicroRNAs/metabolism , Stomach Neoplasms/enzymology , Tetraspanin 29/metabolism , Animals , Cell Line, Tumor , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , Female , Gene Expression Regulation, Neoplastic , HEK293 Cells , Histone Demethylases/genetics , Humans , Mice, Inbred BALB C , Mice, Inbred NOD , Mice, Nude , Mice, SCID , MicroRNAs/genetics , Neoplasm Invasiveness , Neoplasm Metastasis , Signal Transduction , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Tetraspanin 29/geneticsABSTRACT
Natural protoberberine alkaloids were first identified and characterized as potent, selective and cellular active lysine specific demethylase 1 (LSD1) inhibitors. Due to our study, isoquinoline-based tetracyclic scaffold was identified as the key structural element for their anti-LSD1 activity, subtle changes of substituents attached to the core structure led to dramatic changes of the activity. Among these protoberberine alkaloids, epiberberine potently inhibited LSD1 (IC50 = 0.14 ± 0.01 µM) and was highly selective to LSD1 over MAO-A/B. Furthermore, epiberberine could induce the expression of CD86, CD11b and CD14 in THP-1 and HL-60 cells, confirming its cellular activity of inducing acute myeloid leukemia (AML) cells differentiation. Moreover, epiberberine prolonged the survival of THP-1 cells bearing mice and inhibited the growth of AML cells in vivo without obvious global toxicity. These findings give the potential application of epiberberine in AML treatment, and the isoquinoline-based tetracyclic scaffold could be used for further development of LSD1 inhibitors.