Human Promyelocytic Leukemia Cells Research Articles

Inhibition of protein kinases by anticancer DNA intercalator, 4-butylaminopyrimido[4′,5′:4,5]thieno(2,3-b)quinoline

Targeting protein kinases (PKs) has been a promising strategy in treating cancer, as PKs are key regulators of cell survival and proliferation. Here in this study, we studied the ability of pyrimido[4′,5′:4,5]thieno(2,3-b)quinolines (PTQ) to inhibit different PKs by performing computational docking and in vitro screening. Docking studies revealed that 4-butylaminopyrimido[4′,5′:4,5]thieno(2,3-b)quinoline (BPTQ) has a higher order of interaction with the kinase receptors than other PTQ derivatives. In vitro screening confirms that BPTQ inhibits VEGFR1 and CHK2, with the IC50 values of 0.54 and 1.70µmol/L, respectively. Further, cytotoxicity of BPTQ was measured by trypan blue assay. Treatment with BPTQ decreased the proliferation of HL-60 cells with an IC50 value of 12µmol/L and induces apoptosis, as explicated by the fall in the mitochondrial membrane potential, annexin V labeling and increased expression of caspase-3. Taken together, these data suggest that BPTQ possess ability to inhibit PKs and to induce cell death in human promyelocytic leukemia cells.

Differential Maturation of miR-17 ~ 92 Cluster Members in Human Cancer Cell Lines

While some microRNAs are transcribed from a specific promoter, at least one third of human miRNA genes are clustered, wherein multiple miRNA genes are generated from a single primary transcript such as miR-17~92 cluster. Although six members of the cluster are generated from a single transcript, the mature level of each member may be diverse in various cell types. Here, we attempt to monitor the mature level of miR-17, miR-92a, and miR-20a from miR-17~92 cluster in blood (HL60 (human promyelocytic leukemia cells) and Jurkat) and breast (MDA-MB-231 and MCF-7) cancer cell lines. Interestingly, different mature levels of the miRNAs were observed in each cell line. While miR-20 was highly matured in HL60 and MDA-MB-231 cell lines, higher mature level of miR-92a was observed in Jurkat cell line compared to that of miR-20 and miR-17. Further, the mature level of miRNAs was also measured in normal and cancer cell lines. Although the mature level of miR-17 and miR-92a increased in HL60 and Jurkat cell lines, miR-20 expression showed an almost identical level in blood cancer cell lines compared to controls. Conversely, miR-20 mature level significantly increased in breast cancer cell lines whereas the expression level of miR-92a was comparable in MDA-MB-231, MCF-7, and MCF-10A cell lines.

Comparative analysis of microRNA and mRNA expression profiles in cells and exosomes under toluene exposure

Recent studies have illustrated the growing importance of exosomes (small extracellular vesicles) and their constituent microRNAs (miRNAs) in the fields of toxicology and pathology. The mechanism of toxicity of toluene, a highly-prevalent and volatile organic compound, is largely unknown. To examine the role of miRNAs in toluene-induced toxicity, we investigated miRNAs and toluene-induced gene expression in HL-60 human promyelocytic leukemia cells and exosomes using microarrays.A total of 54 miRNAs were differentially expressed in HL-60 cell lines exposed to toluene and exosomes from the cells. Four out of the 54 miRNAs (hsa-miR-1290, hsa-miR-718, hsa-miR-3663-3p, and hsa-miR-320c) were subsequently validated by qRT-PCR. Integrated analysis of miRNA and mRNA expression profiles identified 8 miRNA-mRNA correlations. By performing Comparative Toxicogenomics Database analysis, we found that the eight putative target genes of the differentially expressed miRNAs under toluene exposure (EXOSC6, RHOH, GFER, HERC2, GOLGA4, SLC7A11, GCLM, and BACH1) are related to diverse disease categories such as nervous system disease, cancer, cardiovascular disease, and respiratory tract disease.In conclusion, our data demonstrated that miRNA-mRNA networks provide a better understanding of toxicological mechanism caused by environmental pollutants in vitro using HL-60 cells and exosomes.

Molecular mechanism for apoptosis of leukemia cells induced by chromosome region maintenance 1 selective inhibitor KPT-330

Objective To investigate the induction effect and molecular mechanisms of chromosome region maintenance 1(CRM1) selective inhibitor KPT-330 on apoptosis of human leukemia cells. Methods Human acute promyelocytic leukemia cells(NB4), human chronic myelogenous leukemia cells (K562) and human promyelocytic leukemia cells(HL-60) were divided into a control group(without KPT-330 treatment) and KPT-330 treatment group(NB4, K562 and HL-60 were treated with 0.01, 0.10, 0.20, 0.50, 1.00, 5.00, 10.00 μmol/L KPT-330, respectively). Cell counting kit-8 assay was used to quantify the growth inhibition of cells after exposure to KPT-330.Fluorescence microscope was used to observe the morphological change in leukemia cells when treated with KPT-330.Annexin V/propidium iodide staining followed by flow cytometry was used to detect the apoptosis of leukemia cells.Then, Western blot was used to detect the expression level of CRM1 and the activation of apoptosis marker cysteinyl aspartate specific proteinase-9(Caspase-9), cysteinyl aspartate specific proteinase-3(Caspase-3) and poly ADP-ribose polymerase(PARP). Long non-coding RNA(lncRNA) microarray was used to analyze the differentially expressed genes differentially by the cluster analysis. Results The inhibition of cell proliferation of leukemia cells was in a dose-dependent manner with KPT-330 treatment.Expression of CRM1 was also down-regulated when leukemia cells were treated with KPT-330.Compared with the control group, abnormal cells were observed under fluorescence microscopy.Much more cells showed apoptotic feature after being treated with 0.20 μmol/L and 1.00 μmol/L KPT-330, the apoptosis rate of NB4, K562 and HL-60 were respectively(4.95±0.21)%, (14.05±0.07)%, (4.95±0.63)%(0.20 μmol/L 24 h); (6.10±0.56)%, (20.75±0.21)%, (5.85±0.07)% (0.20 μmol/L 48 h); (41.15±0.21)%, (35.45±0.35)%, (15.65±0.07)% (1.00 μmol/L 24 h); (52.45±0.35)%, (47.45±2.47)%, (16.80±1.98)% (1.00 μmol/L 48 h), respectively, and the differences were statistically significant compared to the control group[24 h NB4, K562, HL-60: (3.30±0.28)%, (9.50±0.56)%, (2.00±0.14)%; 48 h NB4, K562, HL-60: (3.70±0.14)%, (3.50±0.28)%, (2.15±0.21)%](all P<0.05). G2 phase cells obviously reduced and subG1 phase cells increased.The expression level of cleaved Caspase-3, cleaved Caspase-9 and cleaved PARP increased.Molecular function analysis showed that apoptosis induced by KPT-330 in leukemia cells was partially rela-ted to Glutathione metabolism and Toll-like receptor signaling pathway. Conclusions KPT-330 can effectively inhibit proliferation and induce apoptosis of leukemia cells.KPT-330-induced apoptosis in leukemia cells is partially related to Glutathione metabolism and Toll-like receptor signaling pathway. Key words: KPT-330; Chromosome region maintenance 1; Leukemia cell; Apoptosis; Long non-coding RNA

Understanding the Mechanics of Neutrophil Migration in Three-Dimensional Extracellular Matrices

While much research has been dedicated to the identification of the cascade of specific biochemical processes involved in the recruitment of neutrophils, much less is known about the mechanical events driving their migration; in particular, how they generate the necessary traction forces to migrate across three-dimensional (3-D) extravascular spaces and the importance of forming cell-substrate adhesions during this process is unclear. In this study, we investigate the importance of cell-substrate adhesions on the mechanics of 3-D neutrophil motility in collagen gels using Elastographic 3D Force Microscopy (E3DFM). We used wild type neutrophil-like differentiated human promyelocytic leukemia (dHL-60) cells and talin 1 knockout dHL60 cells, which were unable to engage their integrins, as our model systems. Both cell lines were embedded in collagen matrices containing fluorescent micro-beads. Neutrophil motility was induced via the introduction of the neutrophil chemokine formyl-Methionyl-Leucyl-Phenylalanine (fMLP) in a custom build device. Both Confocal and Fluorescent microscopy techniques were used to image the movement of the embedded micro-beads as well as fluorescently labeled cells. Particle Image Velocimetry (PIV) and Finite Deformation Theory were used to compute displacement fields in the collagen matrices. Stress fields in the matrices were computed using our E3DFM method. We will present data showing that morphological changes and migratory patterns differed depending on the cell's ability to form cell-substrate adhesions. We will also provide data showing a clear relationship between the aforementioned migratory characteristics and computed displacement and stress fields around migrating neutrophils in collagen matrices. The results from our study show that neutrophils migrating in 3-D environments employ distinct mechanical mechanisms that depend on their ability to form adhesions.

Cytotoxic Activity of Compounds from Styrax obassia

Cancer is a major public health burden in both developed and developing countries. Plant-derived compounds have played an important role in the development of useful anti-cancer agents. The current study was designed to evaluate the cytotoxic activity of chemical compounds from the stem bark of Styrax obassia. Seven known compounds (1-7) were isolated and identified. Compound 2 exhibited cytotoxic activity against the breast cancer cell line MCF-7 with an IC5₅₀ of 27.9 μM, followed by the human cervical cancer cell line Hela with an IC₅₀ of 23.3 μM, and the human promyelocytic leukemia cell line HL-60 with an IC₅₀ of 47.8 RM. Compound 7 exhibited cytotoxicity against Hela cells with an ICso of 16.8 pM, followed by MCF-7 cells with an IC₅₀ of 53.5 μM. This is the first study to investigate the significant anti-tumor properties of isolated compounds from the stem bark of S. obassia.

Chemical Constituents of the Roots and Rhizomes of Saposhnikovia divaricata and their Cytotoxic Activity

Phytochemical investigation of the MeOH extract of the roots and rhizomes of Saposhnikovia divaricata (Umbelliferae) resulted in the isolation of six chromons (1-6)-and five polyacetylene derivatives (7-11). Compounds 9 and 11 were isolated from S. divaricate for the first time. The chromon derivatives -(1-6) were evaluated for their cytotoxic activity against HL-60 human promyclocytic leukemia cells. Compound 1 (3'-O-angeloylhamaudol) showed the most potent cytotoxic activity with an IC₅₀ value of 4.41 μM and was found to induce apoptotic cell death in HL-60 cells. The loss of mitochondrial membrane potential, release of cytochrome c into the cytoplasm, and activation of caspase-9 in the 1-treated HL-60 cells suggests that I induces apoptosis through the mitochondial-dependent apoptotic pathway.

Highly sensitive detection of E2 activity in ubiquitination using an artificial RING finger.

The ubiquitin-conjugating (E2) enzymes of protein ubiquitination are associated with various diseases such as leukemia, lung cancer, and breast cancer. Rapid and accurate detection of E2 enzymatic activities remains poor. Here, we described the detection of E2 activity on a signal accumulation ISFET biosensor (AMIS sensor) using an artificial RING finger (ARF). The use of ARF enables the simplified detection of E2 activity without a substrate. The high-sensitivity quantitative detection of E2 activities was demonstrated via real-time monitoring over a response range of femtomolar to micromolar concentrations. Furthermore, the monitoring of E2 activities was successfully achieved using human acute promyelocytic leukemia cells following treatment with the anticancer drug bortezomib, which allowed the assessment of the pathological conditions. This strategy is extremely simple and convenient, and the present detection could be widely applied to specific E2s for various types of cancers. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

Raman spectrum reveals Mesenchymal stem cells inhibiting HL60 cells growth

Though some research results reveals that Mesenchymal stem cells (MSCs) have the ability of inhibiting tumor cells proliferation, it remains controversial about the precise interaction mechanism during MSCs and tumor cells co-culture. In this study, combing Raman spectroscopic data and principle component analysis (PCA), the biochemical changes of MSCs or Human promyelocytic leukemia (HL60) cells during their co-culture were presented. The obtained results showed that some main Raman peaks of HL60 assigned to nucleic acids or proteins were greatly higher in intensity in the late stage of co-culture than those in the early stage of co-culture while they were still lower relative to the control group, implicating that the effect of MSCs inhibiting HL60 proliferation appeared in the early stage but gradually lost the inhibiting ability in the late stage of co-culture. Moreover, some other peaks of HL60 assigned to proteins were decreased in intensity in the early stage of co-culture relative to the control group but rebounded to the level similar to the control group in the late stage, showing that the content and structure changes of these proteins might be generated in the early stage but returned to the original state in the late stage of co-culture. As a result, in the early stage of MSCs-HL60 co-culture, along with the level of Akt phosphorylation of HL60 was lowered relative to its control group, the proliferation rate of HL60 cells was decreased. And in the late stage of co-culture, along with the level of Akt phosphorylation was rebounded, the reverse transfer of Raman peaks within 875–880cm−1 appeared, thus MSCs lost the ability to inhibit HL60 growth and HL60 proliferation was increased. In addition, it was observed that the peak at 811cm−1, which is a marker of RNA, was higher in intensity in the late stage than that in the control group, indicating that MSCs might be differentiated into myofibroblast-like MSCs. In addition, PCA results also exhibited that the physiological state of MSCs can be separated by the first two main components of PC1 or PC2 easily, and the effect of MSCs inhibiting HL60 growth was greatly associated with the time of co-culture.

Oxidative Stress and Genotoxicity of Zinc Oxide Nanoparticles to Pseudomonas Species, Human Promyelocytic Leukemic (HL-60), and Blood Cells

In the present study, toxicity of commercial zinc oxide nanoparticles (ZnO NPs) was studied on the bacterium Pseudomonas sp., human promyelocytic leukemia (HL-60) cells, and peripheral blood mononuclear cells (PBMC). The toxicity was assessed by measuring growth, cell viability, and protein expression in bacterial cell. The bacterial growth and viability decreased with increasing concentrations of ZnO NP. Three major proteins, ribosomal protein L1 and L9 along with alkyl hydroperoxides reductase, were upregulated by 1.5-, 1.7-, and 2.0-fold, respectively, after ZnO NP exposure. The results indicated oxidative stress as the leading cause of toxic effect in bacteria. In HL-60 cells, cytotoxic and genotoxic effects along with antioxidant enzyme activity and reactive oxygen species (ROS) generation were studied upon ZnO NP treatment. ZnO NP exhibited dose-dependent increase in cell death after 24-h exposure. The DNA-damaging potential of ZnO NP in HL-60 cells was maximum at 0.05mg/L concentration. Comet assay showed 70-80% increase in tail DNA at 0.025 to 0.05mg/L ZnO NP concentration. A significant increase of 1.6-, 1.4-, and 2.0-fold in ROS level was observed after 12h. Genotoxic potential of ZnO NPs was also demonstrated in PBMC through DNA fragmentation. Thus, ZnO NP, besides being an essential element having antibacterial activity, also showed toxicity towards human cells (HL-60 and PBMC).

Effects of Ligusticum porteri (Osha) Root Extract on Human Promyelocytic Leukemia Cells.

Background:Ligusticum porteri roots have been traditionally used in folk medicine, but the scientific basis is unclear.Objective:To investigate the cytotoxicity, antioxidant, and immunomodulatory effects of L. porteri root extract on human promyelocytic leukemia (HL-60) cells and H2O2-induced oxidative damaged HL-60 cells.Materials and Methods:HL-60 cells were incubated with different concentrations of root extract, and cells were harvested for viability assays on day 3 and 7. Cytokine levels (interferon-gamma [IFN-γ], interleukin-2 [IL-2], and interleukin-10 [IL-10]) and antioxidant indexes (malondialdehyde [MDA], reduced glutathione [GSH], superoxide dismutase [SOD], and catalase [CAT]) in H2O2-induced-stressed HL-60 were measured after 2 days.Results:The viability of HL-60 challenged with H2O2 declined by 42% compared to unstressed cells. After 7 days of incubation with 200 or 400 μg/mL L. porteri, the viability of HL-60 cells was two-fold higher than the control. Stressed HL-60 cells treated with 100, 200, and 400 μg/mL L. porteri reduced the lipid peroxidation by 12%–13%. We noted an increase in GSH levels, SOD and CAT activities in stressed HL-60 supplemented with 400 μg/mL root extract. Treatment with 400 μg/mL L. porteri significantly (P < 0.05) increased IFN-γ and IL-2 in H2O2-challenged cells.Conclusion:Our data do not support the use of the extract as an antiproliferation and differentiation therapy for acute promyelocytic leukemia. The protective function of L. porteri root extract against oxidative stress could occur through increasing GSH and higher expression of antioxidant enzymes.SUMMARY Findings from this study may not support the use of Ligusticum porteri root extract as an antiproliferation and differentiation therapy for acute promyelocytic leukemiaOur data suggest that L. porteri root extract may be a potential antioxidant with protective effect against the oxidation of reduced glutathione (GSH)Treatment with L. porteri root extract may be effective in preventing oxidative damage through increasing the activities of antioxidant enzymes (superoxide dismutase [SOD] and catalase [CAT]) in acute promyelocytic leukemia cells.

Inhibitory Effects of 6-Methylsulfinylhexyl Isothiocyanate on Superoxide Anion Generation from Differentiated HL-60 Human Promyelocytic Leukemia Cells

Wasabi is a plant of Japanese origin. It belongs to the Brassicaceae family and produces various isothiocyanates (ITCs). Because 6-methylsulfinylhexyl isothiocyanate (6-MSITC) is particularly stable among wasabi ITCs, it has potential as a functional compound. To clarify the antioxidative activity of 6-MSITC, we investigated its inhibitory effect on superoxide anion (O2•−) generation from phorbol 12-myristate 13-acetate (PMA)-stimulated differentiated HL-60 human promyelocytic leukemia cells. Our results showed that 6-MSITC inhibited O2•− generation in these cells (IC50 value: 28.9 µM). 6-MSITC at 0.8, 4, and 20 µM significantly inhibited the consumption of exogenously added NADH compared with the control. On the other hand, < 263 µM 6-MSITC did not scavenge O2•− in cell-free experiments. Therefore, we suggest that 6-MSITC inhibited O2•− generation by decreasing an enzymatic reaction with NADPH oxidase. Thus, 6-MSITC may be useful as a functional compound.

Berberine Induces Apoptotic Cell Death via Activation of Caspase-3 and -8 in HL-60 Human Leukemia Cells: Nuclear Localization and Structure-Activity Relationships.

Berberine (BBR), an isoquinoline alkaloid, is a well-known bioactive compound contained in medicinal plants used in traditional and folk medicines. In this study, we investigated the subcellular localization and the apoptotic mechanisms of BBR were elucidated. First, we confirmed the incorporation of BBR into the cell visually. BBR showed antiproliferative activity and promptly localized to the nucleus from 5[Formula: see text]min to 15[Formula: see text]min after BBR treatment in HL-60 human promyelocytic leukemia cells. Next, we examined the antiproliferative activity of BBR (1) and its biosynthetically related compounds (2-7) in HL-60 cells. BBR exerted strongest antiproliferative activity among 1-7 and the results of structures and activity relation suggested that a methylenedioxyl group in ring A, an [Formula: see text]-alkyl group at C-9 position, and the frame of isoquinoline may be necessary for antiproliferative activity. Moreover, BBR showed the most potent antiproliferative activity in HL-60 cells among human cancer and normal cell lines tested. Next, we examined the effect of BBR on molecular events known as apoptosis induction. In HL-60 cells, BBR induced chromatin condensation and DNA fragmentation, and triggered the activation of PARP, caspase-3 and caspase-8 without the activation of caspase-9. BBR-induced DNA fragmentation was abolished by pretreatment with inhibitors against caspase-3 and caspase-8, but not against caspase-9. ERK and p38 were promptly phosphorylated after 15 min of BBR treatment, and this was correlated with time of localization to the nucleus of BBR. These results demonstrated that BBR translocated into nucleus immediately after treatments and induced apoptotic cell death by activation of caspase-3 and caspase-8.

Cultivation of Anaplasma ovis in the HL-60 human promyelocytic leukemia cell line

The tick-borne bacterium Anaplasma ovis is a widely distributed pathogen affecting sheep, goats and wild ruminants. Here, the HL-60 human promyelocytic leukemia cell line was used to isolate A. ovis from PCR-positive sheep and goats in Heilongjiang Province, China. Two weeks after inoculation, morulae were observed in cytoplasmic vacuoles in four different HL-60 cultures. Confocal microscopy using a Cy3-labeled A. ovis-specific probe confirmed that the HL-60 cells were infected with A. ovis. Cells from the 6th HL-60 subculture displayed positive fluorescence when incubated with A. ovis antiserum in the indirect fluorescent antibody assay. PCR amplification and sequencing of 16S rRNA, groEL, gltA, msp2 and msp4 Anaplasma genes revealed that the four A. ovis culture isolates were identical. Phylogenetic analysis showed that the sequences clustered with other A. ovis strains but could clearly be distinguished from other Anaplasma species. When the 18th subculture of infected HL-60 cells was examined by electron microscopy, lysosomes were often observed near the vacuoles. After the 24th subculture, Giemsa staining and PCR indicated that the HL-60 cells were negative for A. ovis. Although A. ovis can infect HL-60 cells for only four months, the ability of the organism to infect and multiply in HL-60 cells provides a tool to study intra-erythrocytic Anaplasma and host cell interactions.Emerging Microbes & Infections (2017) 6, e83; doi:10.1038/emi.2017.70; published online 20 September 2017

Magnetic Nanocarriers Enhance Drug Delivery Selectively to Human Leukemic Cells

Selective drug delivery to human leukemia cells using a nanoparticulate chemotherapeutic formulation is hugely needed. In this work, we report the development of a magnetic nanocarrier made of PVP-stabilized magnetic iron oxide nanoparticles (PMNP) loaded with the anticancer drug Doxorubicin (Dox) as a promising selective drug carrier to different types of human leukemia and normal cells. Our results revealed that while the unloaded MNPs were not potent to any of the cells, Dox@PMNPs showed significant toxicities, effectively killing the different leukemia cells, albeit at different inhibitory concentrations. Interestingly and superior to free Dox, Dox@PMNPs showed enhanced and significant inhibition towards the human monocytic THP-1 cells compared to human promyelocytic leukemia cells HL-60 (2-fold enhanced cytotoxicities), with the least potency towards the normal peripheral blood mononuclear cell (PBMC) cells (up to 6-fold). Nonetheless, free Dox was found to be concurrently less toxic to all the three cell lines tested. The cytotoxic effects obtained were further confirmed by live confocal imaging and electron microscopy. Both imaging techniques confirmed distinct morphological changes (membrane blebbing, shrinkage, and condensation) corresponding to typical apoptotic features in the treated leukemia cells compared to normal PBMC cells. The observed enhanced cytotoxic effects of Dox@PMNPs is mostly dependent upon the selective and differential endocytic uptake of Dox@PMNPs, with subsequent release of Dox intracellularly to the cytoplasm after 6 h, which then translocates to the nucleus after 24 h, causing apoptotic cell death. Importantly, magnetic Dox nanocarrier described here reduces the unwanted diffusive side effects of the free drug and allows selective drug delivery to leukemic cells, allowing its potential use for leukemic patients’ theranostics.

Novel transferrin modified and doxorubicin loaded Pluronic 85/lipid-polymeric nanoparticles for the treatment of leukemia: In vitro and in vivo therapeutic effect evaluation.

Childhood leukemia is a common malignant disease in children. Doxorubicin (DOX) was widely used for the treatment of leukemia. However, severe toxic side effects and drug resistance are the major limitations of DOX. Nanocarriers offer the opportunity to overcome these drawbacks, there are many attempts to enhance the activity of DOX against drug resistance. This study aimed to develop a novel transferrin (Tf) modified and doxorubicin (DOX) loaded Pluronic 85/lipid-polymeric nanoparticles for the treatment of leukemia. In this study, a novel targeted ligand: transferrin-polyethylene glycol-oleic acid (Tf-PEG-OA) was synthesized. Tf modified and DOX loaded Pluronic 85/lipid-polymeric nanoparticles (Tf-DOX P85/LPNs) were prepared via the self-assembly of PLGA, P85, stearic acid and Tf-PEG-OA using the nanoprecipitation method. The physicochemical properties of LPNs were characterized. In vitro and in vivo anti-tumor efficacy of LPNs was evaluated in human promyelocytic leukemia cell line (HL-60 cells) and DOX resistance HL-60 cell line (HL-60/DOX cells) including the relevant animal models. Tf-DOX P85/LPNs displayed strong anti-tumor ability on both HL-60 cells and HL-60/DOX cells than other formulations used as contrast. Also, in HL-60/DOX bearing animal models, Tf-DOX P85/LPNs exhibited the highest efficiency as well as the lowest systemic toxicity. The results indicated that Tf P85/LPNs is a promising platform to enhance efficacy, reduce toxicity and overcome drug resistance of DOX for the treatment of leukemia.

식물화합물 다량 함유 제주조릿대 잎 추출물의 제조와 특성

Sasa species leaves have been used in traditional medicine for their anti-inflammatory, antipyretic, and diuretic properties. Sasa quelpaertensis Nakai is a small bamboo grass that grows only on Mt. Halla on Jeju Island, Republic of Korea. This small bamboo grass has recently been the focus of much attention due to its potential biomass as well as its beneficial health effects. In this study, to promote the efficient utilization of the S. quelpaertensis leaf, we established a simple preparation method for phytochemical-rich extract (PRE) by comparing phytochemical contents and biological activities according to extraction methods. high performance liquid chromatography (HPLC) analysis revealed that the contents of two major phytochemicals such as, tricin (5.35 mg/g) and p-coumaric acid (44.10 mg/g) contained in PRE were higher than those in fresh hot water extract (SQH, p-coumaric 23.39 mg/g, tricin 0.18 mg/g) and ethanol extract (SQE, p-coumaric 10.8 mg/g, tricin 0.38 mg/g). The antioxidant activities [1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activity, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity, nitric oxide (NO) scavenging activity, and xanthine oxidase inhibitory activity] of PRE were higher than those of SQH and SQE. PRE effectively inhibited NO production in LSP- stimulation RAW 264.7 cells, and the growth of human promyelocytic leukemia (HL-60) cells. These results suggest that PRE has a potential as a promising antioxidant and anti-inflammatory agent.

The pattern of GPI-80 expression is a useful marker for unusual myeloid maturation in peripheral blood.

Myeloid-derived suppressor cells (MDSCs) have a wide spectrum of immunosuppressive activity; control of these cells is a new target for improving clinical outcomes in cancer patients. MDSCs originate from unusual differentiation of neutrophils or monocytes induced by inflammatory cytokines, including granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage (GM)-CSF. However, MDSCs are difficult to detect in neutrophil or monocyte populations because they are not uniform cells, resembling both neutrophils and monocytes; thus, they exist in a heterogeneous population. In this study, we investigated GPI-80, a known regulator of Mac-1 (CD11b/CD18) and associated closely with neutrophil maturation, to clarify this unusual differentiation. First, we demonstrated that the mean fluorescence intensity (MFI) of GPI-80 and coefficient of variation (CV) of GPI-80 were increased by treatment with G-CSF and GM-CSF, respectively, using a human promyelocytic leukaemia (HL60) cell differentiation model. To confirm the value of GPI-80 as a marker of unusual differentiation, we measured GPI-80 expression and MDSC functions using peripheral blood cells from metastatic renal cell carcinoma patients. The GPI-80 CV was augmented significantly in the CD16hi neutrophil cell population, and GPI-80 MFI was increased significantly in the CD33hi monocyte cell population. Furthermore, the GPI-80 CV in the CD16hi population was correlated inversely with the proliferative ability of T cells and the GPI-80 MFI of the CD33hi population was correlated with reactive oxygen species production. These results led us to propose that the pattern of GPI-80 expression in these populations is a simple and useful marker for unusual differentiation, which is related to MDSC functions.

4-Biphenylalanine- and 3-Phenyltyrosine-Derived Hydroxamic Acids as Inhibitors of the JumonjiC-Domain-Containing Histone Demethylase KDM4A.

Overexpression of the histone lysine demethylase KDM4A, which regulates H3K9 and H3K36 methylation states, has been related to the pathology of several human cancers. We found that a previously reported hydroxamate-based histone deacetylase (HDAC) inhibitor (SW55) was also able to weakly inhibit this demethylase with an IC50 value of 25.4 μm. Herein we report the synthesis and biochemical evaluations, with two orthogonal in vitro assays, of a series of derivatives of this lead structure. With extensive chemical modifications on the lead structure, also by exploiting the versatility of the radical arylation with aryldiazonium salts, we were able to increase the potency of the derivatives against KDM4A to the low-micromolar range and, more importantly, to obtain demethylase selectivity with respect to HDACs. Cell-permeable derivatives clearly showed a demethylase-inhibition-dependent antiproliferative effect against HL-60 human promyelocytic leukemia cells.

Strepoxazine A, a new cytotoxic phenoxazin from the marine sponge-derived bacterium Streptomyces sp. SBT345

One new phenoxazin analogue, strepoxazine A (1), along with two known antibiotic phenazines phencomycin (2) and tubermycin B (3) were isolated from the solid culture of Streptomyces sp. SBT345 which had previously been recovered from the Mediterranean sponge Agelas oroides. The structures of compounds 1, 2 and 3 were determined by spectroscopic analyses including 1D and 2D NMR, and HR-ESI-MS experiments as well as comparison to the literature. We further investigated the apoptotic effect of the three compounds on the human promyelocytic leukaemia cells HL-60 and human breast adenocarcinoma cells MCF-7. Only strepoxazine A (1) showed cytotoxicity against leukaemia cells HL-60 cells. These results demonstrate that sponge-associated actinomycetes are rich sources for natural products with new pharmacological activities and relevance to drug discovery.