U937 Cancer Cell Research Articles

In vitro cytotoxic activity-guided isolation studies on the underground parts of Valeriana speluncaria Boiss.

Two unreported neolignans, speluncarins A (1) and B (2) together with seven known compounds (3–8, 13) were isolated from the underground parts of Valeriana speluncaria Boiss through cytotoxic activity-guided fractionation method. The crude extract, subextracts, main fractions and isolates were evaluated for their in vitro cytotoxic activities against MCF-7 and U87 cancer cell lines as well as HUVEC cell line by MTS assay. Although the crude EtOH extract, CHCl3 and EtOAc subextracts as well as some fractions exhibited remarkable cytotoxic effect against tested cancer cell lines, the purified compounds did not demonstrate promising activity in the tested concentrations. Besides these studies, five known lignan glucosides (8–12) were obtained from the inactive n-BuOH subextract. The structures of the isolates were elucidated by extensive 1D and 2D NMR spectroscopy and HR-MS analysis. This is the first phytochemical and bioactivity study on V. speluncaria, an endemic species to Turkey.

Near-Infrared Photobiomodulation of Living Cells, Tubulin, and Microtubules In Vitro

We report the results of experimental investigations involving photobiomodulation (PBM) of living cells, tubulin, and microtubules in buffer solutions exposed to near-infrared (NIR) light emitted from an 810 nm LED with a power density of 25 mW/cm2 pulsed at a frequency of 10 Hz. In the first group of experiments, we measured changes in the alternating current (AC) ionic conductivity in the 50–100 kHz range of HeLa and U251 cancer cell lines as living cells exposed to PBM for 60 min, and an increased resistance compared to the control cells was observed. In the second group of experiments, we investigated the stability and polymerization of microtubules under exposure to PBM. The protein buffer solution used was a mixture of Britton-Robinson buffer (BRB aka PEM) and microtubule cushion buffer. Exposure of Taxol-stabilized microtubules (~2 μM tubulin) to the LED for 120 min resulted in gradual disassembly of microtubules observed in fluorescence microscopy images. These results were compared to controls where microtubules remained stable. In the third group of experiments, we performed turbidity measurements throughout the tubulin polymerization process to quantify the rate and amount of polymerization for PBM-exposed tubulin vs. unexposed tubulin samples, using tubulin resuspended to final concentrations of ~ 22.7 μM and ~ 45.5 μM in the same buffer solution as before. Compared to the unexposed control samples, absorbance measurement results demonstrated a slower rate and reduced overall amount of polymerization in the less concentrated tubulin samples exposed to PBM for 30 min with the parameters mentioned above. Paradoxically, the opposite effect was observed in the 45.5 μM tubulin samples, demonstrating a remarkable increase in the polymerization rates and total polymer mass achieved after exposure to PBM. These results on the effects of PBM on living cells, tubulin, and microtubules are novel, further validating the modulating effects of PBM and contributing to designing more effective PBM parameters. Finally, potential consequences for the use of PBM in the context of neurodegenerative diseases are discussed.

Using molecular modeling to identify potential anti‐tubulin compounds

In 2020 the Center for Disease Control and Prevention reported cancer as the second leading cause of death in the United States with over 598,000 cases. Therefore, the need for new innovative cancer drugs is ever‐growing. Tubulin, a protein crucial to cell dynamics, has been the target for many anti‐cancer drugs since the 1960’s. Most anti‐tubulin compounds to date, however, are complex molecules that have issues with solubility, toxicity, multi‐drug resistance, and low efficacy amongst various cancers. The severity of these problems highlights the need to develop a new generation of anti‐tubulin molecules.Previously we synthesized a small vicinal diaryl heterocycle, PY‐407‐C, which showed potent antiproliferative activity against U‐937 cancer cells. Further investigations in vitrodetermined the mode of inhibition is by anti‐tubulin polymerization. Analysis of the known binding sites of tubulin led us to hypothesize PY‐407‐C binds in the tubulin colchicine‐binding site due the similarities of having vicinal diaryl groups. Initial molecular modeling studies were then carried out in AutoDock Vina which strongly supported our predictions. Most significantly, PY‐407‐C makes many hydrophobic and van der Waals interactions within a known hydrophobic pocket of the beta‐tubulin subunit congruent to colchicine, such as L242, L248, L252, L255, T314, V315, I318, N350, K352, and A354.Utilizing these inhibitory docking studies, we hypothesize analogs that theoretically have stronger binding energies than colchicine or PY‐407‐C will also make stronger inhibitors. This allows for an efficient system where synthetic targets are first determined through computational studies, to which they would be synthesized and then tested for biological activity. More specifically, by analyzing interactions between our potential inhibitors and nearby residues, we can make informed decisions on which changes will lead to stronger binding. For example, this methodology led to the design of a new compound for synthesis containing a large hydrophobic propyl‐benzene substituent, which when simulated gave the highest binding affinity of compounds tested thus far.

Biological Evaluation of 3‐Aryl‐4‐indolylfuranones as potential anti‐cancer agents

The American Cancer Society estimates that this year there will be approximately 1.9 million new cases of cancer and nearly 610,000 cancer‐related deaths. The need for new and innovative anticancer drugs is increasingly crucial. One attractive anti‐cancer target is tubulin, which is involved in many cellular functions including cell shape, mitosis, migration, and movement of organelles. While anti‐tubulin drugs have been used to treat cancer for ~70 years, they tend to be complex molecules (derived from natural products), plus suffer from multi‐drug resistance, low solubility, toxicity issues, and/or the lack of multi‐cancer efficacy. These limitations highlight the continued need for the discovery and development of new and novel drugs to enter the pipeline, especially with the significant increase in understanding of tubulin and the mode of action of inhibitors.Using an interdisciplinary approach with undergraduate researchers, we previously developed a furanone‐containing small molecule, PY‐407‐C. The compound demonstrated strong (sub‐micromolar) anti‐proliferative activity in U937 cancer cells. It was submitted for NCI‐60 (National Cancer Institute) screening, which showed nanomolar activity against a variety of cell lines with tubulin as the potential target. We confirmed that it inhibited tubulin polymerization in vitro. We now report on a suite of compounds that are regioisomers of PY‐407‐C and with various moiety modifications. This work has identified new compounds with strong cytotoxicity and important structure‐function information. Overall, these studies provide basic research on small molecule inhibitors of cancer.

Isoquinoline alkaloids from two species of Thalictrum genus plants

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.

Hyaluronic acid-modified, IR780-conjugated and doxorubicin-loaded reduced graphene oxide for targeted cancer chemo/photothermal/photodynamic therapy

We used reduced graphene oxide (rGO), which has two times higher photothermal conversion efficiency than graphene oxide (GO), as a photothermal agent for cancer photothermal therapy (PTT). By conjugating a photosensitizer IR780 to rGO, the IR780-rGO could be endowed with reactive oxygen species (ROSs) generation ability for concurrent photodynamic therapy (PDT). The IR780-rGO was coated with hyaluronic acid (HA) by electrostatic interaction to facilitate its intracellular uptake by U87 glioblastoma cells. The IR780-rGO/HA was loaded with doxorubicin (DOX) for chemotherapy (CT), to develop a pH-responsive drug delivery nano-platform for targeted multimodal cancer CT/PTT/PDT. We fully characterized the properties of all nanocomposites during the synthesis steps. The high loading efficiency of DOX on IR780-rGO-HA provides 3mg/mg drug loading, while IR780-rGO-HA/DOX shows 3 times higher drug release at endosomal pH value (pH5) than at pH7.4. The mechanism for PTT/PDT was confirmed from the ability of IR780-rGO-HA to induce time-dependent temperature rise, synthesis of heat shock protein 70 (HSP70) and generation of intracellular ROSs, after exposure to 808nm near infrared (NIR) laser light. The nano-vehicle IR780-rGO-HA shows high biocompatibility toward 3T3 fibroblast and U87 cancer cell lines, as well as enhanced intracellular uptake by U87 through active targeting. This translates into increased cytotoxicity of IR780-rGO-HA/DOX, by lowering the drug half-maximal inhibitory concentration (IC50) from 0.7 to 0.46μg/mL. This IC50 is further decreased to 0.1μg/mL by irradiation with NIR laser for 3min at 1.5W/cm2. The elevated cancer cell killing mechanism was supported from flow cytometry analysis, where the highest cell apoptosis/necrosis rate was observed in combination CT/PTT/PDT. Using xenograft tumor model created by subcutaneous implantation of U87 cells in nude mice, IR780-rGO-HA/DOX delivered through intravenous (IV) injection and followed with 808nm laser treatment for 5min at 1.5W/cm2 results in the lowest tumor growth rate, with negligible change of tumor volume from its original value at the end 20-day observation period. The therapeutic efficacy was supported from inhibited cell proliferation rate, increased cell apoptosis rate, and increased production of HSP70 from immunohistochemical staining of tumor tissue slices. The safety of the NIR-assisted multimodal cancer treatment could be confirmed from non-significant change of body weight and hematological parameters of blood sample. Taken together, we conclude that IV delivery of IR780-rGO-HA/DOX plus NIR laser treatment is an effective nanomedicine approach for combination cancer therapy.

Chemical constituent of Isochrysis galbana microalgae extract and its cytotoxic activities on leukemic cell lines

Background and Aims: This study was aimed to investigate the anti-cancer effect of Isochrysis galbana microalgae extract. Methods: In the study, the chemical composition of Isochrysis galbana microalgae extract was analyzed, and its cytotoxic effect against K562, HL60, U937, MOLT-4, and Raji cancer cells was investigated. ECV304 endothelial cells were used as a healthy cell line for the understanding of its selective cytotoxicity. To determine the effects of Isochrysis galbana extract, an MTT cytotoxicity assay was performed. Results: According to the results of the experiments, the highest cytotoxic effect of Isochrysis galbana microalgae extract was shown at about 24.07±6.48% cytotoxicity against Raji cells. There were a large number of bioactive molecules in the extract, and these molecules showed a specific response to Raji cells when considering the synergistic and antagonistic effects of these molecules on each other. Conclusion: According to the results of GC-MS analysis of Isochrysis galbana microalgae extract, the most intense molecules in the content were Dodecanoic acid, 3-hydroxy- (CAS) Beta-Hydroxy Dodecanoic Acid, and Propanoic acid, 2-methyl-, 1-(1,1-dimethylethyl)-2-methyl-1,3-isonide. The investigation of the effect of these molecules specifically against Raji cells is important to determine the possible anti-leukemic molecules and their combinations that show cytotoxicity against this cell line.

Leonurus japonicus Houttuyn induces reactive oxygen species-mediated apoptosis via regulation of miR-19a-3p/PTEN/PI3K/AKT in U937 and THP-1 cells

Ethnopharmacological relevanceLeonurus japonicus Houttuyn is a medicinal ingredient in more than 300 prescriptions in traditional Korean medicine. It is especially important for women's health and blood-related diseases. Recent research revealed that Leonurus japonicus Houttuyn extracts have antioxidative, anticancer, analgesic, anti-inflammatory, and neuroprotective properties. Aim of the studyHowever, its underlying anti-cancerous mechanisms remain unclear. This study elucidated the anticancer mechanism of Leonurus japonicus Houttuyn in U937 and THP-1 cancer cells. Materials and methodsHigh-performance liquid chromatography (HPLC) was used for detecting main compound of Leonurus japonicus Houttuyn, rutin. EZ-Cytox cell viability assay, Western blot analysis, live and dead cell assay, 2′, 7’ dichlorofluorescin diacetate (DCFDA) assay, quantitative real-time PCR (qRT-PCR) analysis, and microRNA (miR) mimic transfection assay were applied to further investigate anti-cancer efficacies and underlying mechanism in U937 and THP-1 cells. ResultsThe main compound of Leonurus japonicus Houttuyn, rutin was detected using HPLC. The cytotoxic effect of Leonurus japonicus Houttuyn was exerted in U937 and THP-1 cancer cells but not in MDBK and IEC-6 normal cells. Leonurus japonicus Houttuyn decreased mitochondria membrane potential (ΔΨm). Consistently, Leonurus japonicus Houttuyn reduced the expression of survivin and cleaved caspase-9, caspase-3, and poly (ADP-ribose) polymerase (PARP). Cell death was increased in Leonurus japonicus Houttuyn treated groups. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and CCAAT-enhancer-binding protein homologous protein (CHOP) was increased and phosphatidylinositol-3-kinase (PI3K) and Protein kinase B (AKT) were decreased by Leonurus japonicus Houttuyn. Reactive oxygen speices generation was elevated by Leonurus japonicus Houttuyn and its cytotoxicity was reversed by N-acetyl-l-cysteine (NAC) pretreatment. Moreover, onco-microRNA (miR), miR-19a-3p was suppressed by Leonurus japonicus Houttuyn and transfection of miR-19a-3p mimic reversed the regulated PTEN, p-AKT, CHOP expression, attenuating Leonurus japonicus Houttuyn induced apoptosis. ConclusionsThese findings indicated that Leonurus japonicus Houttuyn has anti-cancer effects by regulation of PTEN/PI3K/AKT signal pathway and ROS-related ER stress-induced apoptosis via regulation of miR-19a-3p. Leonurus japonicus Houttuyn may be an effective candidate for triggering PTEN-dependent apoptosis of cancer cells related to acute myeloid leukemia.

Synergistic effect of Paclitaxel and Curcumin in nano-formulations on U87 and A549 cancer cell lines

Synergistic effect of Paclitaxel and Curcumin in nano-formulations on U87 and A549 cancer cell lines

New Diterpenoids from Mesona procumbens with Antiproliferative Activities Modulate Cell Cycle Arrest and Apoptosis in Human Leukemia Cancer Cells.

Mesona procumbens is a popular material used in foods and herbal medicines in Asia for clearing heat and resolving toxins. However, phytochemical research on this plant is very rare. In this study, eleven new diterpenoids, mesonols A-K (1–11), comprising seven ent-kauranes, three ent-atisanes, and one sarcopetalane, were isolated from its methanolic extract. Structural elucidation of compounds 1–11 was performed by spectroscopic methods, especially 2D NMR, HRESIMS, and X-ray crystallographic analysis. All isolates were assessed for their antiproliferative activity, and compounds 1–4 showed potential antiproliferative activities against A549, Hep-3B, PC-3, HT29, and U937 cancer cells, with IC50 values ranging from 1.97 to 19.86 µM. The most active compounds, 1 and 2, were selected for further investigation of their effects on cell cycle progression, apoptosis, and ROS generation in U937 human leukemia cancer cells. Interestingly, it was found that compounds 1 and 2 induced antiproliferative effects in U937 cells through different mechanisms. Compound 1 caused cell cycle arrest at the G2/M phase and subsequent cell death in a dose- and time-dependent manner. However, 2-mediated antiproliferation of U937 cells triggered ROS-mediated mitochondrial-dependent apoptosis. These results provide insight into the molecular mechanism involved in the antiproliferative activities of compounds 1 and 2 in U937 cells. Altogether, the study showed that new diterpenoid compounds 1 and 2 from M. procumbens are potent and promising anticancer agents.

Ca2+ roles in electroporation-induced changes of cancer cell physiology: From membrane repair to cell death

The combination of Ca2+ ions and electroporation has gained attention as potential alternative to electrochemotherapy. Ca2+ is an important component of the cell membrane repair system and its presence directly influences the dynamics of the pore cycle after electroporation which can be exploited for cancer therapies. Here, the influence of Ca2+ concentration is investigated on small molecule electrotransfer and release of Calcein from 4T1, MX-1, B16F10, U87 cancer cells after cell exposure to microsecond electric pulses. Moreover, we investigated simultaneous molecule electrotransfer and intracellular calcium ion influx when media was supplemented with different Ca2+ concentrations. Results show that increased concentrations of calcium ions reduce the electrotransfer of small molecules to different lines of cancer cells as well as the release of Calcein. These effects are related with an enhanced membrane repair mechanism. Overall, we show that the efficiency of molecular electrotransfer can be controlled by regulating Ca2+ concentration in the electroporation medium. For the first time, the cause of cancer cell death in vitro from 1 mM CaCl2 concentrations is related to the irreversible loss of Ca2+ homeostasis after cell electroporation. Our findings provide fundamental insight on the mechanisms of Ca2+ electroporation that might lead to improved therapeutic outcomes.

Thio-substituted derivatives of 4-amino-pyrazolo[3,4-d]pyrimidine-6-thiol as antiproliferative agents.

The current study was designed toidentifynew compounds as potential antiproliferative drug candidates. Synthesis of heteroaromatic bicyclic and monocyclic derivatives as purine bioisosters was employed. Their antiproliferative activity was studied against U937 cancer cells. The most effective compounds were evaluated for their selectivity against cancer cells, the possible mechanism of cell death, and their interference with DNA replication. Among the synthesized compounds, only three (4b, 4j and 4l) demonstrated a value of IC50 less than 20μM. However, two of them (4b and 4l) were specific against cancer cells, with 4l presentinghigh selectivity. The presence of substituted pyrazolo[3,4-d]pyrimidine core is asessential for this activityas the presence of substituents at the thiol function in 6-position.

Fomitopsis cajanderi extracts have differential tumoricidal actions on human MCF7 and U-937 cancer cells and inhibit TNF secretion by U-937 monocytes

Abstract This study aimed to determine if hot ethanol and aqueous extracts from the Fomitopsis cajanderi mushroom species are cytotoxic to human cancer cell lines and modulate TNF secretion by human monocytes. The hot ethanol extract was made via a 2 hour Soxhlet extraction of F. cajanderi fruiting body in ethanol using a cold finger condenser. The hot aqueous extract was made via a 2 hour decoction in water at 100°C. Human MCF7 mammary adenocarcinoma and U-937 histiocytic lymphoma cells were treated with increasing concentrations of extract or solvent controls and were assessed for cytotoxicity by XTT colorimetric assay. Effects of the aqueous extract on TNF secretion by PMA-differentiated, LPS-stimulated U-937 cells were determined by TNF ELISA. Glycosyl content and linkage analysis of the aqueous extract were assessed by the Complex Carbohydrate Research Center (Athens, Georgia, USA). The hot ethanol extract induced concentration-dependent cytotoxicity of MCF7 and U-937 cells, with stronger U-937 tumoricidal effects. The hot aqueous extract was not cytotoxic to MCF7 cells, but had cytotoxic effects on undifferentiated U-937 cells at high concentrations. The aqueous extract, found to contain beta glucans, inhibited TNF secretion by LPS-stimulated U-937 cells in a concentration-dependent manner. Hot ethanol and aqueous F. cajanderi extracts showed differential tumoricidal actions on human cancer cells. The ethanol extract was cytotoxic to the human cancer cells tested. The aqueous extract contained beta glucans reported to be immunomodulatory, and inhibited U-937 TNF secretion. These results warrant further research of F. cajanderi extracts as novel adjunctive anti-cancer and anti-inflammatory agents.

The Effect of SP/NK1R on the Expression and Activity of Catalase and Superoxide Dismutase in Glioblastoma Cancer Cells.

Introduction Glioblastoma is the most malignant brain tumor with different therapeutic protocols, including surgery, radiotherapy, and chemotherapy. Substance P (SP), a peptide released by sensory nerves, increases cellular excitability by activating the neurokinin-1 receptor (NK1R) in several human tumor cells. Aprepitant is a potent and long-lasting NK1R antagonist, considered a new agent for inhibiting proliferation and induction of apoptosis in malignant cells. This study aimed to evaluate the effects of the SP/NK1R system on the expression and activity of catalase and superoxide dismutase (SOD) in the glioblastoma U87 cancer cell line. Methods Cytotoxicity was measured by the resazurin test, 24 hours after treatment, with increasing aprepitant concentrations. The production of reactive oxygen species (ROS) was also measured 24 hours after treatment with SP and aprepitant. Enzymes activity of catalase and SOD was measured using the corresponding assay kits. Real-time PCR also measured their expression. Results Aprepitant significantly reduced the viability of U87 cells in a concentration-dependent manner. ROS production was significantly reduced, and the activity of catalase and SOD increased after treatment with aprepitant. The expression of catalase and SOD enzymes also increased significantly in the presence of aprepitant. Conclusion The present study showed that aprepitant inhibited SP's oxidizing effects via inducing the antioxidant effects of catalase and SOD in the U87 cell line. Therefore, this drug might be introduced as a potential candidate for controlling glioblastoma cancer in animal models and clinical trials.

Discovery of an indole-substituted furanone with tubulin polymerization inhibition activity

Analogs of diarylpyrrolinone lead compound 1 were prepared and tested for anti-proliferative activity in U-937 cancer cells. Alterations of 1 focused on modifying the two nitrogen atoms: a) the pyrrolinone nitrogen atom was substituted with a propyl group or replaced with an oxygen atom (furanone), and b) the substituents on the indole nitrogen were varied. These changes led to the discovery of a furanone analog 3b with sub-micromolar anti-cancer potency and tubulin polymerization inhibition activity.

Enhancement of the brain delivery of methotrexate with administration of mid-chain ester prodrugs: In vitro and in vivo studies

In the present study, with the aim of improving the permeability of methotrexate (MTX) to the brain, the lipophilic MTX prodrugs containing the ester functional moiety were synthesized. The chemical structure of synthesized prodrugs was characterized and confirmed by FT-IR, NMR and mass spectral studies. Based on the results of in vitro cytotoxic studies, all of the synthesized prodrugs led to decrease in the IC50 in 72 h on U87 cancer cell line and the best result was observed for dihexyl methotrexate (MTX-DH) in comparison with free MTX, which led to decrease the IC50 amount up to 6 folds. In addition, in vivo toxicity on Artemia salina (A. salina) showed that the lipophilic MTX prodrugs have been able to partially mask the toxic profile of free MTX, at the same concentrations. These findings were also in compliance with hemolysis assay results, which confirm that the conjugates has not made the drug more toxic. Furthermore, in vivo study in rat model, was employed to determine the simultaneous drug concentration in brain and plasma. According to the obtained results, the brain-to-plasma concentration ratios (Kp values) of MTX-DH and dioctyl methotrexate (MTX-DO) groups were significantly higher compared with free MTX. Moreover, the uptake clearance of MTX by brain parenchyma increased significantly (3.85 and 9.08-time increased for MTX-DH and MTX-DO prodrugs, respectively). These findings indicate that the synthesized lipophilic MTX prodrugs are non-toxic and able to enhance brain penetration of MTX.

Indolyl-α-keto-1,3,4-oxadiazoles: Synthesis, anti-cell proliferation activity, and inhibition of tubulin polymerization

A series of novel indolyl-α-keto-1,3,4-oxadiazole derivatives have been synthesized by employing molecular iodine-mediated oxidative cyclization of acylhydrazones. In vitro anti cell proliferation activity of these derivatives against various cancer cells lines such as human lymphoblast (U937), leukemia (Jurkat & SB) and human breast (BT474) was investigated. Among the synthesized indolyl-α-keto-1,3,4-oxadiazoles 19a-p, only one compound (19e) exhibited significant antiproliferative activity against a panel of cell lines. The compound 19e with 3,4,5-trimethoxyphenyl motif, endowed strong cytotoxicity against U937, Jurkat, BT474 and SB cancer cells with IC50 values of 7.1, 3.1, 4.1, and 0.8 µM, respectively. Molecular docking studies suggested a potential binding mode for 19e in the colchicine binding site of tubulin. When tested for in vitro tubulin polymerizaton, 19e inhibited tubulin polymezations (IC50 = 10.66 µM) and induced apoptosis through caspase 3/7 activation. Further, the derivative 19e did not cause necrosis when measured using lactate dehydrogenase assay.

Design, synthesis and antitumor evaluations of nucleoside base hydroxamic acid derivatives as DNMT and HDAC dual inhibitors

DNA methyltransferase (DNMT) and histone deacetylase (HDAC) are well recognized epigenetic targets for discovery of antitumor agents. In this study, we designed and synthesized a series of nucleoside base hydroxamic acid derivatives as DNMT and HDAC dual inhibitors. MTT assays and enzymatic inhibitory activity tests indicated that compound 204 exhibited potent DNMT1 and HDAC1/6 inhibitory potency simultaneously in enzymatic levels and at cellular levels, inducing hypomethylation of p16 and hyperacetylation of histones H3K9 and H4K8. Besides, 204 remarkably inhibited proliferation against cancer cells U937 by prompting G0/G1 cell cycle arrest. Molecular docking models explained the functional mechanism of 204 inhibiting DNMT1 and HDAC. Preliminary studies on metabolic profiles revealed that 204 showed desirable stability in liver microsomes. Our study suggested that 204 inhibiting DNMT and HDAC concurrently can be a potential lead compound for epigenetic cancer therapy.

Covalently Labeled Fluorescent Exosomes for In Vitro and In Vivo Applications.

The vertiginous increase in the use of extracellular vesicles and especially exosomes for therapeutic applications highlights the necessity of advanced techniques for gaining a deeper knowledge of their pharmacological properties. Herein, we report a novel chemical approach for the robust attachment of commercial fluorescent dyes to the exosome surface with covalent binding. The applicability of the methodology was tested on milk and cancer cell-derived exosomes (from U87 and B16F10 cancer cells). We demonstrated that fluorescent labeling did not modify the original physicochemical properties of exosomes. We tested this nanoprobe in cell cultures and healthy mice to validate its use for in vitro and in vivo applications. We confirmed that these fluorescently labeled exosomes could be successfully visualized with optical imaging.

Anticancer Activity of Kefir on Glioblastoma Cancer Cell as a New Treatment.

Kefir drink is one of the most important probiotic products, which is made using kefir microorganisms in fermenting the milk. Numerous investigation have been accomplished in the field of the therapeutic property of probiotic products. In the present study, we assessed the cytotoxic effect of kefir on the rate of growth and increase of glioblastoma cancer cell as the most severe form of brain tumors. In this experimental study, we used a U87 cancer cell line (glioblastoma). The interaction between cancer cells and different concentrations of kefir drink and supernatants at 24 and 48 hours was considered. The cell cytotoxicity of kefir and sedimentation of cell lysate and extract of kefir was assessed using the MTT test after 24 and 48 hours. The result of the MTT test, treatment of the cells with the 48-hour fermented drink, demonstrated the most cell cytotoxicity in comparison with the control group. Results showed that the toxicity effect in all groups was dose-dependent, and by increasing the concentration, cell survival decreased noticeably. The results indicated that the supernatant of fermented kefir drink as a probiotic product has more toxicity and lethality effect on the glioblastoma cancer cell. This product can be utilized as a replacement or a complementary therapy of cancer.