BACKGROUND: T-cell lymphoblastic lymphoma/acute lymphoblastic leukemia (T-LBL/ALL) is an aggressive form of hematological malignancy associated with poor prognosis in adult patients. Histone deacetylases (HDACs) are aberrantly expressed in T-LBL/ALL and are considered potential therapeutic targets. Here, we investigated the antitumor effect of a novel HDAC inhibitor, chidamide, on T-LBL/ALL. METHODS: HDAC1, HDAC2 and HDAC3 levels in T-LBL/ALL cell lines and patient samples were compared with those in normal controls. Flow cytometry, transmission electron microscopy, and lactate dehydrogenase release assays were conducted in Jurkat and MOLT-4 cells to assess apoptosis and pyroptosis. A specific forkhead box O1 (FOXO1) inhibitor was used to rescue pyroptosis and upregulated gasdermin E (GSDME) expression caused by chidamide treatment. The role of the FOXO1 transcription factor was evaluated by dual-luciferase reporter and chromatin immunoprecipitation assays. The efficacy of chidamide in vivo was evaluated in a xenograft mouse. RESULTS: The expression of HDAC1, HDAC2 and HDAC3 was significantly upregulated in T-LBL/ALL. Cell viability was obviously inhibited after chidamide treatment. Pyroptosis, characterized by cell swelling, pore formation on the plasma membrane and lactate dehydrogenase leakage, was identified as a new mechanism of chidamide treatment. Chidamide triggered pyroptosis through caspase 3 activation and GSDME transcriptional upregulation. Chromatin immunoprecipitation assays confirmed that chidamide led to the increased transcription of GSDME through a more relaxed chromatin structure at the promoter and the upregulation of FOXO1 expression. Moreover, we identified the therapeutic effect of chidamide in vivo . CONCLUSIONS This study suggested that chidamide exerts an antitumor effect on T-LBL/ALL and promotes a more inflammatory form of cell death via the FOXO1/GSDME axis, which provides a novel choice of targeted therapy for patients with T-LBL/ALL.
Humans ; Pyroptosis/drug effects* ; Forkhead Box Protein O1/genetics* ; Aminopyridines/pharmacology* ; Animals ; Mice ; Benzamides/pharmacology* ; Cell Line, Tumor ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy* ; Phosphate-Binding Proteins/metabolism* ; Histone Deacetylase Inhibitors/pharmacology* ; Jurkat Cells ; Histone Deacetylases/metabolism* ; Apoptosis/drug effects* ; Gasdermins

OBJECTIVE: To investigate the effects of histone deacetylase (HDAC) levels on the proliferation and apoptosis of Burkitt lymphoma cells, and the changes in related signaling molecules in the PI3K/AKT/mTOR signaling pathway, so as to explore the pathogenesis of Burkitt lymphoma. METHODS: HDAC levels in Burkitt lymphoma were detected by RT-PCR and Western blot. CA46 and RAJI cells were treated with the HDAC selective inhibitor VPA. CCK8 assay was used to detect the proliferation ability of cells. Western Blot was used to measure the expression of apoptosis-related proteins, PI3K/AKT/mTOR signaling pathway proteins and their phosphorylation levels. RESULTS: The expression levels of classⅠ HDAC in Burkitt lymphoma were higher than those in normal cells, and the HDAC1 inhibitor VPA could inhibit the proliferation of CA46 and RAJI cells. VPA decreased HDAC expression in CA46 and RAJI cells, inhibited the phosphorylation of PI3K/AKT/mTOR pathway molecules AKT and p70S6K, increased the expression of apoptotic proteins Cleaved Caspase-3, Cleaved Caspase-8, Cleaved Caspase-9 and Bax, and decreased the expression of anti-apoptotic proteins Bcl-2 and PARP. CONCLUSION Inhibition of HDAC activity can Attenuate the proliferation of Burkitt lymphoma cells and induce apoptosis by inhibiting the PI3K/AKT/mTOR signaling pathway activity.
Humans ; Burkitt Lymphoma/pathology* ; Apoptosis ; Cell Proliferation ; Signal Transduction ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Cell Line, Tumor ; Histone Deacetylases/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Histone Deacetylase Inhibitors/pharmacology* ; Phosphorylation

Sepsis is a life-threatening organ dysfunction caused by the host's dysregulated response to infection, with a complex pathogenesis and high mortality rate. Currently, there are no clear and effective treatment drugs available. Epigenetic modification serves as a major mechanism regulating gene expression under pathological and physiological conditions, and it has been shown to play a critical role in regulating the occurrence and development of sepsis. Histone acetylation modification, as a sophisticated epigenetic modification mechanism, plays a crucial regulatory role in many aspects of life. It can jointly regulate the acetylation status of histones through histone acetyltransferase (HAT) and histone deacetylase (HDAC), thereby changing DNA expression and dynamically regulating sepsis related gene expression at the epigenetic level. Previous studies have shown that histone acetylation can participate in the progression of sepsis by regulating inflammatory mediators, nuclear factor-ΚB (NF-ΚB) signaling pathway, autophagy, efferocytosis, ferroptosis, pyroptosis. These mechanisms are promising targets for novel sepsis treatments. In addition, with the deepening of research, it has been found that various selective/non selective histone deacetylase inhibitors (HDACI) can regulate histone acetylation status by acting on different HDAC targets, which has been shown to alleviate organ damage caused by sepsis and improve prognosis in septic animal models. This article further summarizes the role and potential applications of histone acetylation in sepsis, providing new ideas for the treatment of sepsis.
Sepsis/metabolism* ; Acetylation ; Humans ; Histones/metabolism* ; Histone Acetyltransferases/metabolism* ; Histone Deacetylase Inhibitors ; Epigenesis, Genetic ; Histone Deacetylases/metabolism* ; Signal Transduction ; NF-kappa B/metabolism* ; Animals

OBJECTIVES: Subarachnoid hemorrhage (SAH) is a serious cerebrovascular disease. Early brain injury (EBI) and cerebral vasospasm are the main reasons for poor prognosis of SAH patients. The specific inhibitor of histone deacetylase 6 (HDAC6), tubastatin A (TubA), has been proved to have a definite neuroprotective effect on a variety of animal models of acute and chronic central nervous system diseases. However, the neuroprotective effect of TubA on SAH remains unclear. This study aims to investigate the expression and localization of HDAC6 in the early stage of SAH, and to evaluate the protective effects of TubA on EBI and cerebral vasospasm after SAH and the underlying mechanisms. METHODS: Adult male SD rats were treated with modified internal carotid artery puncture to establish SAH model. In the first part of the experiment, rats were randomly divided into 6 groups: a sham group, a SAH-3 h group, a SAH-6 h group, a SAH-12 h group, a SAH-24 h group, and a SAH-48 h group. At 3, 6, 12, and 24 h after SAH modeling, the injured cerebral cortex of rats in each group was taken for Western blotting to detect the expression of HDAC6. In addition, the distribution of HDAC6 in the cerebral cortex of the injured side was measured by immunofluorescence double staining in SAH-24 h group rats. In the second part, rats were randomly divided into 4 groups: a sham group, a SAH group, a SAH+TubA_L group (giving 25 mg/kg TubA), and a SAH+TubA_H group (giving 40 mg/kg TubA). At 24 h after modeling, the injured cerebral cortex tissue was taken for Western blotting to detect the expression levels of HDAC6, endothelial nitric oxide synthase (eNOS), and inducible nitric oxide synthase (iNOS), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining to detect apoptosis, and hematoxylin and eosin (HE) staining to detect the diameter of middle cerebral artery. RESULTS: The protein expression of HDAC6 began to increase at 6 h after SAH (P<0.05), peaked at 24 h (P<0.001), and decreased at 48 h, but there was still a difference compared with the sham group (P<0.05). HDAC6 is mainly expressed in the cytoplasm of the neurons. Compared with the sham group, the neurological score was decreased significantly and brain water content was increased significantly in the SAH group (both P<0.01). Compared with the SAH group, the neurological score was increased significantly and brain water content was decreased significantly in the SAH+TubA_H group (both P<0.05), while the improvement of the above indexes was not significant in the SAH+TubA_L group (both P>0.05). Compared with the sham group, the expression of eNOS was significantly decreased (P<0.01) and the expressions of iNOS and HDAC6 were significantly increased (P<0.05 and P<0.01, respectively) in the SAH group. Compared with the SAH group, the expression of eNOS was significantly increased, and iNOS and HDAC6 were significantly decreased in the SAH+TubA group (all P<0.05). Compared with the SAH group, the number of TUNEL positive cells was significantly decreased and the diameter of middle cerebral artery was significantly increased in the SAH+TubA group (both P<0.05) . CONCLUSIONS HDAC6 is mainly expressed in neurons and is up-regulated in the cerebral cortex at the early stage of SAH. TubA has protective effects on EBI and cerebral vasospasm in SAH rats by reducing brain edema and cell apoptosis in the early stage of SAH. In addition, its effect of reducing cerebral vasospasm may be related to regulating the expression of eNOS and iNOS.
Rats ; Male ; Animals ; Rats, Sprague-Dawley ; Subarachnoid Hemorrhage/drug therapy* ; Vasospasm, Intracranial/metabolism* ; Histone Deacetylase Inhibitors/therapeutic use* ; Neuroprotective Agents/therapeutic use* ; Histone Deacetylase 6/pharmacology* ; Apoptosis ; Brain Injuries/drug therapy*

CUDC-101, an effective and multi-target inhibitor of epidermal growth factor receptor (EGFR), histone deacetylase (HDAC), and human epidermal growth factor receptor 2 (HER2), has been reported to inhibit many kinds of cancers, such as acute promyelocytic leukemia and non-Hodgkin's lymphoma. However, no studies have yet investigated whether CUDC-101 is effective against myeloma. Herein, we proved that CUDC-101 effectively inhibits the proliferation of multiple myeloma (MM) cell lines and induces cell apoptosis in a time- and dose-dependent manner. Moreover, CUDC-101 markedly blocked the signaling pathway of EGFR/phosphoinositide-3-kinase (PI3K) and HDAC, and regulated the cell cycle G2/M arrest. Moreover, we revealed through in vivo experiment that CUDC-101 is a potent anti-myeloma drug. Bortezomib is one of the important drugs in MM treatment, and we investigated whether CUDC-101 has a synergistic or additive effect with bortezomib. The results showed that this drug combination had a synergistic anti-myeloma effect by inducing G2/M phase blockade. Collectively, our findings revealed that CUDC-101 could act on its own or in conjunction with bortezomib, which provides insights into exploring new strategies for MM treatment.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis ; Bortezomib/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; ErbB Receptors/antagonists & inhibitors* ; G2 Phase Cell Cycle Checkpoints ; Histone Deacetylase Inhibitors/pharmacology* ; Histone Deacetylases/metabolism* ; M Cells ; Multiple Myeloma/drug therapy*

Antibody-mediated rejection (AMR) is one of the major causes of graft loss after transplantation. Recently, the regulation of B cell differentiation and the prevention of donor-specific antibody (DSA) production have gained increased attention in transplant research. Herein, we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin (FK228) on DSA. The survival of grafted skins was monitored daily. The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry. Then, we isolated and purified B cells from B6 mouse spleens in vitro by magnetic bead sorting. The B cells were cultured with interleukin-4 (IL-4) and anti-clusters of differentiation 40 (CD40) antibody with or without FK228 treatment. The immunoglobulin G1 (IgG1) and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay (ELISA). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were conducted to determine the corresponding levels of messenger RNA (mRNA) and protein expression in cultured cells and the recipient spleens. The results showed that FK228 significantly improved the survival of allogeneic skin grafts. Moreover, FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1 (HADC1) and HDAC2 and the upregulation of the acetylation of histones H2A and H3. It also inhibited the differentiation of B cells to plasma cells, decreased the transcription of positive regulatory domain-containing 1 (Prdm1) and X-box-binding protein 1 (Xbp1), and decreased the expression of phosphorylated inositol-requiring enzyme 1 α (p-IRE1α), XBP1, and B lymphocyte-induced maturation protein-1 (Blimp-1). In conclusion, FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway. Thus, FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.
Animals ; Depsipeptides ; Endoribonucleases ; Hematopoietic Stem Cell Transplantation ; Histone Deacetylase Inhibitors/pharmacology* ; Mice ; Protein Serine-Threonine Kinases ; Skin Transplantation

Mice ; Animals ; Acetylation ; NF-kappa B/metabolism* ; Histone Deacetylases/metabolism* ; Inflammation ; Histone Deacetylase Inhibitors

OBJECTIVE: To explore the role of chidamide in the regulatory mechanism of PD-1/PD-L1 immune escape signaling pathway in peripheral T-cell lymphoma. METHODS: Jurkat cell line was treated with different concentrations of chidamide. The changes of PD-L1 and JAK/STAT pathway gene mRNA expression and PD-L1 protein expression on cell surface were detected by fluorescence quantitative PCR and flow cytometry after treatment. RESULTS: Chidamide upregulated PD-L1 mRNA expression in Jurkat cell line in a dose-dependent manner (r=0.989). The mRNA expression of PD-L1 in 5.0 μmol/L group was 15.4 times higher than that in the control group. The proportion of PD-L1 positive cells in Jurkat cell line was less than 0.5%. Chidamide upregulated PD-L1 protein expression on Jurkat cell surface. Chidamide upregulated the mRNA expression of JAK2, STAT1 and STAT3 in Jurkat cell line. The level of up-regulation was obvious in high concentration group (5.0 μmol/L group). Meanwhile, the mRNA expression of SOCS1 and SOCS3, the negative regulatory genes upstream of the JAK/STA T pathway, were up-regulated. CONCLUSION In peripheral T-cell lymphoma, chidamide may up-regulate the expression of cell surface PD-L1 and induce T-cell chemokines by upregulation of STAT1 expression, thus improving the reaction rate of PD-1 monoclonal antibody and T-cell toxicity.
Humans ; Lymphoma, T-Cell, Peripheral ; Histone Deacetylase Inhibitors ; B7-H1 Antigen ; Janus Kinases ; Programmed Cell Death 1 Receptor ; Signal Transduction ; STAT Transcription Factors

Diffuse large B-cell lymphoma (DLBCL) is an aggressive type of non-Hodgkin's lymphoma. A total of 10%‒15% of DLBCL cases are associated with myelocytomatosis viral oncogene homolog(MYC) and/or B-cell lymphoma-2 (BCL2) translocation or amplification. BCL2 inhibitors have potent anti-tumor effects in DLBCL; however, resistance can be acquired through up-regulation of alternative anti-apoptotic proteins. The histone deacetylase (HDAC) inhibitor chidamide can induce BIM expression, leading to apoptosis of lymphoma cells with good efficacy in refractory recurrent DLBCL. In this study, the synergistic mechanism of chidamide and venetoclax in DLBCL was determined through in vitro and in vivo models. We found that combination therapy significantly reduced the protein levels of MYC, TP53, and BCL2 in activated apoptotic-related pathways in DLBCL cells by increasing BIM levels and inducing cell apoptosis. Moreover, combination therapy regulated expression of multiple transcriptomes in DLBCL cells, involving apoptosis, cell cycle, phosphorylation, and other biological processes, and significantly inhibited tumor growth in DLBCL-bearing xenograft mice. Taken together, these findings verify the in vivo therapeutic potential of chidamide and venetoclax combination therapy in DLBCL, warranting pre-clinical trials for patients with DLBCL.
Aminopyridines ; Animals ; Benzamides ; Biological Phenomena ; Bridged Bicyclo Compounds, Heterocyclic ; Down-Regulation ; Histone Deacetylase Inhibitors/therapeutic use* ; Humans ; Lymphoma, Large B-Cell, Diffuse/pathology* ; Mice ; Neoplasm Recurrence, Local ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Proto-Oncogene Proteins c-myc/therapeutic use* ; Sulfonamides ; Tumor Suppressor Protein p53/metabolism*

The self-renewal and differentiation of hematopoietic stem cells(HSCs)are highly regulated by epigenetic modification,in which histone acetylation can activate or silence gene transcription.Histone deacetylase inhibitors(HDACIs)can inhibit the activity of histone deacetylase in HSCs to increase histone acetylation.A variety of HDACIs,such as trichostatin A and valproic acid,are used to expand HSCs in vitro,especially cord blood HSCs,combined with cytokines in serum-free culture to obtain more long-term repopulating cells.HDACIs promote the transcription of pluripotent genes related to stem cell self-renewal and inhibit the expression of genes related to differentiation,so as to promote the expansion and inhibit differentiation of HSCs.The expansion of cord blood HSCs by small molecular HDACIs in vitro is expected to improve the quantity of cord blood HSCs.The further research will focus on high-throughput screening for the most powerful HDACIs and the highly selective HDACIs,exploring the combination of epigenetic modifiers of different pathways.
Epigenesis, Genetic ; Fetal Blood ; Hematopoietic Stem Cells ; Histone Deacetylase Inhibitors/pharmacology* ; Valproic Acid/pharmacology*