Neuroreceptor Inhibition by Clozapine Triggers Mitohormesis and Metabolic Reprogramming in Human Blood Cells.

The antipsychotic drug clozapine demonstrates superior efficacy in treatment-resistant schizophrenia, but its intracellular mode of action is not completely understood. Here, we analysed the effects of clozapine (2.5-20 µM) on metabolic fluxes, cell respiration, and intracellular ATP in human HL60 cells. Some results were confirmed in leukocytes of clozapine-treated patients. Neuroreceptor inhibition under clozapine reduced Akt activation with decreased glucose uptake, thereby inducing ER stress and the unfolded protein response (UPR). Metabolic profiling by liquid-chromatography/mass-spectrometry revealed downregulation of glycolysis and the pentose phosphate pathway, thereby saving glucose to keep the electron transport chain working. Mitochondrial respiration was dampened by upregulation of the F0F1-ATPase inhibitory factor 1 (IF1) leading to 30-40% lower oxygen consumption in HL60 cells. Blocking IF1 expression by cotreatment with epigallocatechin-3-gallate (EGCG) increased apoptosis of HL60 cells. Upregulation of the mitochondrial citrate carrier shifted excess citrate to the cytosol for use in lipogenesis and for storage as triacylglycerol in lipid droplets (LDs). Accordingly, clozapine-treated HL60 cells and leukocytes from clozapine-treated patients contain more LDs than untreated cells. Since mitochondrial disturbances are described in the pathophysiology of schizophrenia, clozapine-induced mitohormesis is an excellent way to escape energy deficits and improve cell survival.

Systems Biology for Drug Target Discovery in Acute Myeloid Leukemia.

Combining new therapeutics with all-trans-retinoic acid (ATRA) could improve the efficiency of acute myeloid leukemia (AML) treatment. Modeling the process of ATRA-induced differentiation based on the transcriptomic profile of leukemic cells resulted in the identification of key targets that can be used to increase the therapeutic effect of ATRA. The genome-scale transcriptome analysis revealed the early molecular response to the ATRA treatment of HL-60 cells. In this study, we performed the transcriptomic profiling of HL-60, NB4, and K562 cells exposed to ATRA for 3-72 h. After treatment with ATRA for 3, 12, 24, and 72 h, we found 222, 391, 359, and 1032 differentially expressed genes (DEGs) in HL-60 cells, as well as 641, 1037, 1011, and 1499 DEGs in NB4 cells. We also found 538 and 119 DEGs in K562 cells treated with ATRA for 24 h and 72 h, respectively. Based on experimental transcriptomic data, we performed hierarchical modeling and determined cyclin-dependent kinase 6 (CDK6), tumor necrosis factor alpha (TNF-alpha), and transcriptional repressor CUX1 as the key regulators of the molecular response to the ATRA treatment in HL-60, NB4, and K562 cell lines, respectively. Mapping the data of TMT-based mass-spectrometric profiling on the modeling schemes, we determined CDK6 expression at the proteome level and its down-regulation at the transcriptome and proteome levels in cells treated with ATRA for 72 h. The combination of therapy with a CDK6 inhibitor (palbociclib) and ATRA (tretinoin) could be an alternative approach for the treatment of acute myeloid leukemia (AML).

Identification of triciribine as a novel myeloid cell differentiation inducer.

Differentiation therapy using all-trans retinoic acid (ATRA) for acute promyelocytic leukemia (APL) is well established. However, because the narrow application and tolerance development of ATRA need to be improved, we searched for another efficient myeloid differentiation inducer. Kinase activation is involved in leukemia biology and differentiation block. To identify novel myeloid differentiation inducers, we used a Kinase Inhibitor Screening Library. Using a nitroblue tetrazolium dye reduction assay and real-time quantitative PCR using NB4 APL cells, we revealed that, PD169316, SB203580, SB202190 (p38 MAPK inhibitor), and triciribine (TCN) (Akt inhibitor) potently increased the expression of CD11b. We focused on TCN because it was reported to be well tolerated by patients with advanced hematological malignancies. Nuclear/cytoplasmic (N/C) ratio was significantly decreased, and myelomonocytic markers (CD11b and CD11c) were potently induced by TCN in both NB4 and acute myeloid leukemia (AML) M2 derived HL-60 cells. Western blot analysis using NB4 cells demonstrated that TCN promoted ERK1/2 phosphorylation, whereas p38 MAPK phosphorylation was not affected, suggesting that activation of the ERK pathway is involved in TCN-induced differentiation. We further examined that whether ATRA may affect phosphorylation of ERK and p38, and found that there was no obvious effect, suggesting that ATRA induced differentiation is different from TCN effect. To reveal the molecular mechanisms involved in TCN-induced differentiation, we performed microarray analysis. Pathway analysis using DAVID software indicated that "hematopoietic cell lineage" and "cytokine-cytokine receptor interaction" pathways were enriched with high significance. Real-time PCR analysis demonstrated that components of these pathways including IL1ß, CD3D, IL5RA, ITGA6, CD44, ITGA2B, CD37, CD9, CSF2RA, and IL3RA, were upregulated by TCN-induced differentiation. Collectively, we identified TCN as a novel myeloid cell differentiation inducer, and trials of TCN for APL and non-APL leukemia are worthy of exploration in the future.

Verification of In Vitro Anticancer Activity and Bioactive Compounds in Cordyceps Militaris-Infused Sweet Potato Shochu Spirits.

Many liqueurs, including spirits infused with botanicals, are crafted not only for their taste and flavor but also for potential medicinal benefits. However, the scientific evidence supporting their medicinal effects remains limited. This study aims to verify in vitro anticancer activity and bioactive compounds in shochu spirits infused with Cordyceps militaris, a Chinese medicine. The results revealed that a bioactive fraction was eluted from the spirit extract with 40% ethanol. The infusion time impacted the inhibitory effect of the spirit extract on the proliferation of colon cancer-derived cell line HCT-116 cells, and a 21-day infusion showed the strongest inhibitory effect. Furthermore, the spirit extract was separated into four fractions, A-D, by high-performance liquid chromatography (HPLC), and Fractions B, C, and D, but not A, exerted the effects of proliferation inhibition and apoptotic induction of HCT-116 cells and HL-60 cells. Furthermore, Fractions B, C, and D were, respectively, identified as adenosine, cordycepin, and N6-(2-hydroxyethyl)-adenosine (HEA) by comprehensive chemical analyses, including proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FT-IR), and electrospray ionization mass spectrometry (ESI-MS). To better understand the bioactivity mechanisms of cordycepin and HEA, the agonist and antagonist tests of the A3 adenosine receptor (A3AR) were performed. Cell viability was suppressed by cordycepin, and HEA was restored by the A3AR antagonist MR1523, suggesting that cordycepin and HEA possibly acted as agonists to activate A3ARs to inhibit cell proliferation. Molecular docking simulations revealed that both adenosine and cordycepin bound to the same pocket site of A3ARs, while HEA exhibited a different binding pattern, supporting a possible explanation for the difference in their bioactivity. Taken together, the present study demonstrated that cordycepin and HEA were major bioactive ingredients in Cordyceps militaries-infused sweet potato shochu spirits, which contributed to the in vitro anticancer activity.

Effective delivery of anti-PD-L1 siRNA with human heavy chain ferritin (HFn) in acute myeloid leukemia cell lines.

Because of the high biocompatibility, self-assembly capability, and CD71-mediated endocytosis, using human heavy chain ferritin (HFn) as a nanocarrier would greatly increase therapeutic effectiveness and reduce possible adverse events. Anti-PD-L1 siRNA can downregulate the level of PD-L1 on tumor cells, resulting in the activation of effector T cells against leukemia. Therefore, this study aimed to produce the tumor-targeting siPD-L1/HFn nanocarrier. Briefly, the HFn coding sequence was cloned into a pET-28a, and the constructed expression plasmid was subsequently transformed into E. coli BL21. After induction of Isopropyl ß-D-1-thiogalactopyranoside (IPTG), HFn was purified with Ni-affinity chromatography and dialyzed against PBS. The protein characteristics were analyzed using SDS-PAGE, Western Blot, and Dynamic light scattering (DLS). The final concentration was assessed using the Bicinchoninic acid (BCA) assay. The encapsulation was performed using the standard pH system. The treatment effects of siPD-L1/HFn were carried out on HL-60 and K-562 cancer cell lines. The RT-PCR was used to determine the mRNA expression of PD-L1. The biocompatibility and excretion of siPD-L1/HFn have also been evaluated. The expression and purity of HFn were well verified through SDS-PAGE, WB, and DLS. RT-PCR analyses also showed significant siRNA-mediated PD-L1 silencing in both HL-60 and K-562 cells. Our study suggested a promising approach for siRNA delivery. This efficient delivery system can pave the way for the co-delivery of siRNAs and multiple chemotherapies to address the emerging needs of cancer combination therapy.

Design, Synthesis, Computational Studies, and Anti-Proliferative Evaluation of Novel Ethacrynic Acid Derivatives Containing Nitrogen Heterocycle, Urea, and Thiourea Moieties as Anticancer Agents.

In the present work, the synthesis of new ethacrynic acid (EA) derivatives containing nitrogen heterocyclic, urea, or thiourea moieties via efficient and practical synthetic procedures was reported. The synthesised compounds were screened for their anti-proliferative activity against two different cancer cell lines, namely, HL60 (promyelocytic leukaemia) and HCT116 (human colon carcinoma). The results of the in vitro tests reveal that compounds 1-3, 10, 16(a-c), and 17 exhibit potent anti-proliferative activity against the HL60 cell line, with values of the percentage of cell viability ranging from 20 to 35% at 1 µM of the drug and IC50 values between 2.37 µM and 0.86 µM. Compounds 2 and 10 showed a very interesting anti-proliferative activity of 28 and 48% at 1 µM, respectively, against HCT116. Two PyTAP-based fluorescent EA analogues were also synthesised and tested, showing good anti-proliferative activity. A test on the drug-likeness properties in silico of all the synthetised compounds was performed in order to understand the mechanism of action of the most active compounds. A molecular docking study was conducted on two human proteins, namely, glutathione S-transferase P1-1 (pdb:2GSS) and caspase-3 (pdb:4AU8) as target enzymes. The docking results show that compounds 2 and 3 exhibit significant binding modes with these enzymes. This finding provides a potential strategy towards developing anticancer agents, and most of the synthesised and newly designed compounds show good drug-like properties.

[Prognostic Value of IGF2BP3 Gene Expression Levels in Patients with Acute Myeloid Leukemia].

OBJECTIVE: To investigate the relationship between IGF2BP3 gene expression and prognosis in patients with acute myeloid leukemia (AML). METHODS: High throughput transcriptome sequencing was performed on bone marrow primary leukemia cells from 27 patients with AML in our center, the relationship between IGF2BP3 expression levels and clinical characteristics were analyzed and verify the samples from patients with newly treated AML and refractory AML. The expression level of IGF2BP3 gene were analyzed in 20 healthy subjects and 26 patients with AML. The expression of IGF2BP3 in two anthracycline-resistant cell lines (HL60/ADR, K562/ADR) was detected by RT-qPCR and Western blot, and the expression difference of IGF2BP3 was compared with that in sensitive cells (HL60, K562). The relationship between the expression level of IGF2BP3 in patients with AML and prognostic were analyzed through data analysis of 746 patients with AML, and the prognostic value of IGF2BP3 in AML was analyzed by multivariate Cox regression analysis. RESULTS: In the bone marrow primary leukemia cells of 27 AML patients in our center, the expression level of IGF2BP3 in patients with refractory AML was significantly higher than that in chemotherapy sensitive patients (P =0.0343). The expression of IGF2BP3 in leukemia patients with extramedullary infiltration (EMI) was significantly higher than that in AML patients without extramedullary infiltration (P =0.0049). Compared with healthy subjects (n=20), IGF2BP3 expression in AML patients (n=26) was higher (P =0.0009). The expression of IGF2BP3 mRNA in the anthracycline resistant cell lines (HL60/ADR, K562/ADR) was significantly higher than that in the sensitive cell lines (K562/ADR vs K562,P =0.0430; HL60/ADR vs HL60, P =0.7369). Western blot results showed that the expression of IGF2BP3 protein in mycin resistant cells was significantly higher than that in sensitive cells (P < 0.001). qPCR results showed that the expression level of IGF2BP3 mRNA in refractory AML patients was significantly higher than that in patients with chemotherapy sensitive (P =0.002). High expression of IGF2BP3 was associated with poor prognosis in AML (P < 0.05) in 3 large sample cohorts of AML patients. Univariate and multivariate prognostic analyses demonstrated that high expression of IGF2BP3 was significantly associated with shorter event-free survival (EFS, HR=1.887, P =0.024) and overall survival (OS, HR=1.619, P =0.016). CONCLUSION: The high expression of IGF2BP3 gene may be an important factor in the poor prognosis of AML, suggesting that IGF2BP3 gene may be a new molecular marker for the clinical prognosis evaluation and treatment strategy of AML.

[Effects of BMAL2 on Aerobic Glycolysis and Cell Proliferation in Acute Myeloid Leukemia Cells].

OBJECTIVE: To explore the expression of basic helix-loop-helix ARNT like 2 (BMAL2) in acute myeloid leukemia (AML) patients and its correlation with prognosis, and analyze its effects on the aerobic glycolysis and proliferation of AML cells. METHODS: The expressions of BMAL2 in bone marrow mononuclear cells (BMMCs) of AML patients and normal control group were detected by RT-qPCR. The correlation of BMAL2 expression with prognosis of AML patients was analyzed using public database of National Center for Biotechnology Information (NCBI). The interfering in BMAL2 expression of HL-60 and Kasumi-1 cells was performed using lentiviral vector-mediated shRNA. Cell glucose metabolism and proliferation were detected by using glucose uptake experiment, lactate content test, CCK-8 assay and cell colony formation test. RESULTS: The expression level of BMAL2 mRNA in BMMCs of AML patients was significantly higher than normal control group (P < 0.01). The overall survival time of AML patients with high expression of BMAL2 was significantly shorter than those with low expression of BMAL2 (P < 0.05). Knockdown of BMAL2 significantly reduced glucose uptake and lactate production in AML cell line HL-60 and Kasumi-1 cells. The results of RT-PCR and Western blot showed that BMAL2 promoted aerobic glycolysis by enhancing the expression of HIF1A in AML cells, thereby promoting cell proliferation. CONCLUSION: BMAL2 is highly expressed in AML patients, and promotes aerobic glycolysis by enhancing the expression of HIF1A, thereby promoting cell proliferation.

[Elesclomol-Cu Induces Cuproptosis in Human Acute Myeloid Leukemia Cells].

OBJECTIVE: To investigate the effects of elesclomol-Cu (ES-Cu) on the proliferation and cuproptosis of human acute myeloid leukemia (AML) cells. METHODS: The effects of ES-Cu on the proliferation of AML cells and the AML cells pre-treated with ammonium tetrathiomolybdate (TTM) were examined by CCK-8 assay. The Calcein/PI kit was used to detected the changes in activity and cytotoxicity of AML cells induced by ES-Cu. Flow cytometry and Cytation3 fully automated cell imaging multifunctional detection system were used to analyze DCFH-DA fluorescence intensity, so as to determine the level of reactive oxygen species (ROS). The GSH and GSSG detection kits were used to measure the intracellular GSH content. Western blot was used to detected the expression of cuproptosis-related proteins ATP7B, FDX1, DLAT and DPYD. RESULTS: ES-Cu inhibited the proliferation of Kasumi-1 and HL-60 cells in a concentration-dependent manner (r Kasumi-1=-0.99， r HL-60=-0.98). As the concentration of ES-Cu increased, the level of intracellular ROS also increased (P <0.01-0.001). TTM could significantly reverse the inhibitory effect of ES-Cu on cell proliferation and its promoting effect on ROS. With the increase of ES-Cu concentration, the content of GSH was decreased (r =-0.98), and Western blot showed that the protein expressions of ATP7B, FDX1, DLAT and DPYD were significantly reduced (P <0.05). CONCLUSION: ES-Cu can induce cuproptosis in AML cells, which provides a new idea for the treatment of AML.

Fucosylation inhibitor 6-alkynylfucose enhances the ATRA-induced differentiation effect on acute promyelocytic leukemia cells.

For acute promyelocytic leukemia (APL), differentiation therapy with all-trans retinoic acid (ATRA) is well established. However, the narrow application and tolerance development of ATRA remain to be improved. In this study, we investigated the effects of combinations of glycosylation inhibitors with ATRA to achieve better efficiency than ATRA alone. We found that the combination of fucosylation inhibitor 6-alkynylfucose (6AF) and ATRA had an additional effect on cell differentiation, as revealed by expression changes in two differentiation markers, CD11b and CD11c, and significant morphological changes in NB4 APL and HL-60 acute myeloid leukemia (AML) cells. In AAL lectin blot analyses, ATRA or 6AF alone could decrease fucosylation, while their combination decreased fucosylation more efficiently. To clarify the molecular mechanism for the 6AF effect on ATRA-induced differentiation, we performed microarray analyses using NB4 cells. In a pathway analysis using DAVID software, we found that the C-type lectin receptor (CLR) signaling pathway was enriched with high significance. In real-time PCR analyses using NB4 and HL-60 cells, FcεRIγ, CLEC6A, CLEC7A, CASP1, IL-1ß, and EGR3, as components of the CLR pathway, as well as CD45 and AKT3 were upregulated by 6AF in ATRA-induced differentiation. Taken together, the present findings suggest that the CLR signaling pathway is involved in the 6AF effect on ATRA-induced differentiation.

In vitro anti-leukemic effect of Wharton's jelly derived mesenchymal stem cells.

BACKGROUND: Mesenchymal stem cells (MSCs) have the ability to self-renew and are multi-potent. They are a primary candidate for cell-based therapy due to their potential anti-cancer effects. The aim of this study was to evaluate the in vitro anti-leukemic effect of Wharton's Jelly-derived MSC (WJ-MSC) on the leukemic cell lines K562 and HL-60. METHODS: In this present study, WJ-MSCs were isolated from human umbilical cord. The cells were incubated according to the standard culture conditions and characterized by flow cytometry. For experiments, WJ-MSC and leukemic cells were incubated in the direct co-culture at a ratio of 1:5 (leukemia cells: WJ-MSC). HUVEC cells were used as a non-cancerous cell line model. The apoptotic effect of WJ-MSCs on the cell lines was analyzed using Annexin V/PI apoptosis assay. RESULTS: After the direct co-culture of WJ-MSCs on leukemic cell lines, we observed anti-leukemic effects by inducing apoptosis. We had two groups of determination apoptosis with and without WJ-MSCs for all cell lines. Increased apoptosis rates were observed in K562 and HL-60 cell lines, whereas the apoptosis rates in HUVEC cells were low. CONCLUSIONS: MSCs are known to inhibit the growth of tumors of both hematopoietic and non-hematopoietic origin in vitro. In our study, WJ-MSC treatment strongly inhibited the viability of HL-60 and K562 and induced apoptosis. Our results also provided new insights into the inhibition of tumor growth by WJ-MSCs in vitro. In the future, WJ-MSCs could be used to inhibit cancer cells in clinical applications.

Batimastat Induces Cytotoxic and Cytostatic Effects in In Vitro Models of Hematological Tumors.

The role of metalloproteinases (MMPs) in hematological malignancies, like acute myeloid leukemia (AML), myelodysplastic neoplasms (MDS), and multiple myeloma (MM), is well-documented, and these pathologies remain with poor outcomes despite treatment advancements. In this study, we investigated the effects of batimastat (BB-94), an MMP inhibitor (MMPi), in single-administration and daily administration schemes in AML, MDS, and MM cell lines. We used four hematologic neoplasia cell lines: the HL-60 and NB-4 cells as AML models, the F36-P cells as an MDS model, and the H929 cells as a model of MM. We also tested batimastat toxicity in a normal human lymphocyte cell line (IMC cells). BB-94 decreases cell viability and density in a dose-, time-, administration-scheme-, and cell-line-dependent manner, with the AML cells displaying higher responses. The efficacy in inducing apoptosis and cell cycle arrests is dependent on the cell line (higher effects in AML cells), especially with lower daily doses, which may mitigate treatment toxicity. Furthermore, BB-94 activated apoptosis via caspases and ERK1/2 pathways. These findings highlight batimastat's therapeutic potential in hematological malignancies, with daily dosing emerging as a strategy to minimize adverse effects.

Ring finger protein 138 inhibits transcription factor C/EBPα protein turnover leading to differentiation arrest in acute myeloid leukemia.

E3 ubiquitin ligase, ring finger protein 138 (RNF138) is involved in several biological processes; however, its role in myeloid differentiation or tumorigenesis remains unclear. RNAseq data from TNMplot showed that RNF138 mRNA levels are highly elevated in acute myeloid leukemia (AML) bone marrow samples as compared with bone marrow of normal volunteers. Here, we show that RNF138 serves as an E3 ligase for the tumor suppressor CCAAT/enhancer binding protein (C/EBPα) and promotes its degradation leading to myeloid differentiation arrest in AML. Wild-type RNF138 physically interacts with C/EBPα and promotes its ubiquitin-dependent proteasome degradation while a mutant RNF-138 deficient in ligase activity though interacts with C/EBPα, fails to down-regulate it. We show that RNF138 depletion enhances endogenous C/EBPα levels in peripheral blood mononuclear cells (PBMCs) isolated from healthy volunteers. Our data further shows that RNF138-mediated degradation of C/EBPα negatively affects its transactivation potential on its target genes. Furthermore, RNF138 overexpression inhibits all-trans-retinoic acid-induced differentiation of HL-60 cells whereas RNF138 RNAi enhances. In line with RNF138 inhibiting C/EBPα protein turnover, we also observed that RNF138 overexpression inhibited ß-estradiol (E2)-induced C/EBPα driven granulocytic differentiation in C/EBPα inducible K562-p42C/EBPα-estrogen receptor cells. Furthermore, we also recapitulated these findings in PBMCs isolated from AML patients where depletion of RNF138 increased the expression of myeloid differentiation marker CD11b. These results suggest that RNF138 inhibits myeloid differentiation by targeting C/EBPα for proteasomal degradation and may provide a plausible mechanism for loss of C/EBPα expression often observed in myeloid leukemia. Also, targeting RNF138 may resolve differentiation arrest by restoring C/EBPα expression in AML.

Duocarmycin SA Reduces Proliferation and Increases Apoptosis in Acute Myeloid Leukemia Cells In Vitro.

Acute myeloid leukemia (AML) is a hematological malignancy that is characterized by an expansion of immature myeloid precursors. Despite therapeutic advances, the prognosis of AML patients remains poor and there is a need for the evaluation of promising therapeutic candidates to treat the disease. The objective of this study was to evaluate the efficacy of duocarmycin Stable A (DSA) in AML cells in vitro. We hypothesized that DSA would induce DNA damage in the form of DNA double-strand breaks (DSBs) and exert cytotoxic effects on AML cells within the picomolar range. Human AML cell lines Molm-14 and HL-60 were used to perform 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), DNA DSBs, cell cycle, 5-ethynyl-2-deoxyuridine (EdU), colony formation unit (CFU), Annexin V, RNA sequencing and other assays described in this study. Our results showed that DSA induced DNA DSBs, induced cell cycle arrest at the G2M phase, reduced proliferation and increased apoptosis in AML cells. Additionally, RNA sequencing results showed that DSA regulates genes that are associated with cellular processes such as DNA repair, G2M checkpoint and apoptosis. These results suggest that DSA is efficacious in AML cells and is therefore a promising potential therapeutic candidate that can be further evaluated for the treatment of AML.

Halimane Derivatives from Plectranthus ornatus Codd. as Novel Anti-cancer Agents.

The Plectranthus genus is often cited for its medicinal properties. Plectranthus ornatus Codd. is traditionally used in Africa for the treatment of gastric and liver diseases and their leaves are used for their antibiotic action. The main constituent of P. ornatus is the halimane compound, 11 R∗-acetoxyhalima-5,13E-dien-15-oic acid (Hal), described for its antimicrobial and anticancer properties. The objective of this work was to improve the activity of the halimane lead molecule. Further physiochemical characterisation was performed on Hal. To the best of our knowledge, this work constitutes the first published data of the absolute configurations by SCXRD and thermal stability of Hal. Using Hal, reactions with different amines were carried out to afford novel semi-synthetic derivatives and their structural elucidation was completed. The cytotoxicity of the derivatives was assessed against three leukaemia cancer cell lines (CCRF-CEM, K562 and HL-60). The antioxidant activity was investigated using H2O2-induced HGF-1 cells and their anti-inflammatory activity was studied using RT-PCR and ELISA. Our data showed that amide derivatives of Hal presented moderate cytotoxicity and more potent activity when compared to the parent molecule, giving insight into the SAR of Hal. The derivatives also displayed protection against oxidative damage to DNA. Finally, the derivatives possessed anti-inflammatory properties at the level of gene and protein expression for the cytokines IL-1ß, TNF-α and IL-6, induced by LPS in normal HGF-1 cells. Overall, our study provides useful insight into the enhanced biological activities of semi-synthetic Hal derivatives, as a starting point for novel drug formulations in cancer therapy.

Activin A signaling stimulates neutrophil activation and macrophage migration in pancreatitis.

Acute Pancreatitis (AP) is associated with high mortality and current treatment options are limited to supportive care. We found that blockade of activin A (activin) in mice improves outcomes in two murine models of AP. To test the hypothesis that activin is produced early in response to pancreatitis and is maintained throughout disease progression to stimulate immune cells, we first performed digital spatial profiling (DSP) of human chronic pancreatitis (CP) patient tissue. Then, transwell migration assays using RAW264.7 mouse macrophages and qPCR analysis of "neutrophil-like" HL-60 cells were used for functional correlation. Immunofluorescence and western blots on cerulein-induced pancreatitis samples from pancreatic acinar cell-specific Kras knock-in (Ptf1aCreER™; LSL-KrasG12D) and functional WT Ptf1aCreER™ mouse lines mimicking AP and CP to allow for in vivo confirmation. Our data suggest activin promotes neutrophil and macrophage activation both in situ and in vitro, while pancreatic activin production is increased as early as 1 h in response to pancreatitis and is maintained throughout CP in vivo. Taken together, activin is produced early in response to pancreatitis and is maintained throughout disease progression to promote neutrophil and macrophage activation.

Possible nonimmunological toxicological mechanisms of vesnarinone-associated agranulocytosis in HL-60 cells: role of reduced glutathione as cytotoxic defense.

This study was conducted as part of an investigation into the cause of vesnarinone-associated agranulocytosis. When HL-60 cells were exposed to vesnarinone for 48 hr, little cytotoxicity was observed, although reduced glutathione (GSH) content decreased in a concentration-dependent manner. Significant cytotoxicity and reactive oxygen species (ROS) production were observed when intracellular GSH content was reduced by treatment with L-buthionine-(S, R)-sulphoximine. The involvement of myeloperoxidase (MPO) metabolism was suggested, as when HL-60 cells were exposed to a reaction mixture of vesnarinone-MPO/H2O2/Cl-, cytotoxicity was also observed. In contrast, the presence of GSH (1 mM) protected against these cytotoxic effects. Liquid chromatography-mass spectrometry analysis of the MPO/H2O2/Cl- reaction mixture revealed that vesnarinone was converted into two metabolites, (4-(3,4-dimethoxybenzoyl)piperazine [Metabolite 1: M1] and 1-chloro-4-(3,4-dimethoxybenzoyl)piperazine [Metabolite 2: M2]). M2 was identified as the N-chloramine form, a reactive metabolite of M1. Interestingly, M2 was converted to M1, which was accompanied by the conversion of GSH to oxidized GSH (GSSG). Furthermore, when HL-60 cells were exposed to synthetic M1 and M2 for 24 hr, M2 caused dose-dependent cytotoxicity, whereas M1 did not. Cells were protected from M2-derived cytotoxicity by the presence of GSH. In conclusion, we present the first demonstration of the cytotoxic effects and ROS production resulting from the MPO/H2O2/Cl- metabolic reaction of vesnarinone and newly identified the causative metabolite, M2, as the N-chloramine metabolite of M1, which induces cytotoxicity in HL-60 cells. Moreover, a protective role of GSH against the cytotoxicity was revealed. These findings suggest a possible nonimmunological cause of vesnarinone agranulocytosis.

Effects of chronic hydrogen peroxide exposure on mitochondrial oxidative stress genes, ROS production and lipid peroxidation in HL60 cells.

Hydrogen peroxide (H2O2) is a reactive species that is also involved in the redox regulation of cells because of it is relative stability. In numerous pathological situations, a chronic increase in the production of reactive species is observed, which is related to oxidative stress and cellular damage. This study aimed to evaluate the effects of long-term exposure to different H2O2 concentrations on oxidative stress biomarkers and mitochondrial dynamics in HL60 cells. HL60 cells were treated with a sustained production (0.1, 1.0 and 10.0 nM/s) of H2O2 for one hour. H2O2 production and malondialdehyde (MDA) levels, as a lipid peroxidation marker, increased progressively in HL60 cells in accordance with higher H2O2 exposure, with significant differences between the 10 nM/s H2O2 group and the control and 0.1 nM/s groups. Similarly, progressive increased expression in genes related to the mitochondrial antioxidant defences and mitochondrial dynamics were also observed. Significantly increased gene expression in the 10 nM/s H2O2 with respect to the control group was observed for manganese superoxide dismutase (MnSOD), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PCG1α), nuclear respiratory factor 2 (Nrf2), mitochondrial transcription factor A (Tfam), mitofusins 1 and 2 (Mfn1 and Mfn2) and uncoupling protein 3 (UCP3), whereas no significant changes were observed in the cytochrome c oxidase subunit IV (COXIV) gene expression. In conclusion, exposure to different sustained production of H2O2 is related to a progressive increase in the gene expression of mitochondrial dynamics and redox processes in HL60 cells, but also to oxidative damage at higher H2O2 production levels.

Neutrophil-like cells derived from the HL-60 cell-line as a genetically-tractable model for neutrophil degranulation.

Research on neutrophil biology has been limited by the short life span and limited genetic manipulability of these cells, driving the need for representative and efficient model cell lines. The promyelocytic cell line HL-60 and its subline PLB-985 can be differentiated into neutrophil-like cells (NLCs) and have been used to study neutrophil functions including chemotaxis, phagocytosis, endocytosis, and degranulation. Compared to neutrophils derived from hematopoietic stem cells, NLCs serve as a cost-effective neutrophil model. NLCs derived from both HL-60 and PLB-985 cells have been shown to perform degranulation, an important neutrophil function. However, no study has directly compared the two lines as models for degranulation including their release of different types of mobilizable organelles. Furthermore, Nutridoma, a commercially available supplement, has recently been shown to improve the chemotaxis, phagocytosis, and oxidative burst abilities of NLCs derived from promyelocytic cells, however it is unknown whether this reagent also improves the degranulation ability of NLCs. Here, we show that NLCs derived from both HL-60 and PLB-985 cells are capable of degranulating, with each showing markers for the release of multiple types of secretory organelles, including primary granules. We also show that differentiating HL-60 cells using Nutridoma does not enhance their degranulation activity over NLCs differentiated using Dimethyl Sulfoxide (DMSO) plus Granulocyte-colony stimulating factor (G-CSF). Finally, we show that promyelocytic cells can be genetically engineered and differentiated using these methods, to yield NLCs with a defect in degranulation. Our results indicate that both cell lines serve as effective models for investigating the mechanisms of neutrophil degranulation, which can advance our understanding of the roles of neutrophils in inflammation and immunity.

[The Effect of TCP1 Expression on the Proliferation and the Accumulation of Intracellular Drug of HL60/A and HL60 Cell and Its Mechanism].

OBJECTIVE: To investigate the effect of TCP1 expression on the proliferation and the accumulation of intracellular drug of HL60/A and HL60 cells and its possible molecular mechanism. METHODS: Lentiviral transfection technology was used to construct HL60/A and HL60 cells with knocked down or overexpressed TCP1 and their control cells. The efficiency of knockdown and overexpression was evaluated by Western blot. The cell proliferation was detected by CCK-8 assay. The intracellular drug accumulation was detected by laser confocal detection and flow cytometry. The expression levels of MRP1, P-gP and p-AKT were evaluated by flow cytometry and Western blot. RESULTS: After TCP1 was knocked down,the proliferation ability of HL60/A cells was significantly reduced, the accumulation of intracellular drug was significantly increased and the expression of MRP1 and P-gP protein were decreased. After TCP1 was overexpressed, the proliferation ability of HL60 was significantly increased, the accumulation of intracellular drug was significantly decreased and the expression of MRP1 and P-gP protein were increased. Intervention of LY294002 significantly antagonized the promotion on cell proliferation, the inhibition on intracellular drug accumulation and the expression of MRP1 and P-gP mediated by TCP1 overexpressing in HL60 cells. CONCLUSION: TCP1 can promote cell proliferation, improve the expression of MRP1 and P-gP by activating PI3K/AKT signal, and reduce intracellular drug accumulation.