Non-cancerous Human Cell Line Research Articles

Carbon dots-embedded N-acetylneuraminic acid and glucuronic acid-imprinted polymers for targeting and imaging of cancer cells.

Diagnosis, treatment, and prediction of cancer progression require new targeting agents to specifically target cell surface receptors. Herein, we demonstrated fluorescent carbon quantum dots-molecularly imprinted polymer (CQD-MIP) for selective targeting and imaging of cancer cells. Carbon quantum dots (CQDs) were synthesized and characterized. The synthesized CQDs had average size of 1.5nm and show intense fluorescence emission at wavelength of 450nm with excitation at 370nm. CQD-MIP nanoparticles imprinted with N-acetylneuraminic acid and glucuronic acid were prepared and characterized. CQD-MIPs were successfully applied for selective targeting and imaging of MCF-7, HepG-2, and NIH-3T3 cell lines. Non-imprinted polymer (NIP) showed no binding properties toward a target molecule. Non-imprinted polymer (NIP) and non-cancerous human cell lines were used for controlling the imprinting and targeting effects, respectively. Acceptable results were obtained with imprinted polymers on cancer cells.

Design, synthesis and pharmacological evaluation of novel Artemisinin-Thymol

A molecular hybridization of natural products is a new concept in drug discovery and having critical roles to design new molecules with improved biological properties. Hybrid molecules display higher biological activities when compared to the parent drugs. In the present study, two natural products (thymol and artemisinin (ART)) are used for the synthesis of new hybrid thymol-artemisinin. After characterization, the cytotoxic activity of ART-thymol was tested against different cancer cell lines and non-cancerous human cell line. ART-Thymol show the cytotoxic effect with EC50 values 70,96μM for HepG2, 97,31μM for LnCap, 6,03μM for Caco-2, 77,98μM for HeLa and 62,28μM for HEK293 cells, respectively. Moreover, ART-Thymol was checked for drug-likeness, and the kinase inhibitory activity. ART-Thymol is investigated by using molecular docking. The results of qPCR was indicated CDK2 and P38 were inhibited by ART-Thymol. These results improved that thymol-artemisinin may be new candidates as an anticancer agents.

New oxygen-containing androstane derivatives: Synthesis and biological potential

New steroidal D-homo androstane derivatives with 5β,6β-epoxy-3,16-dicarbonyl, 6α- and 6β-hydroxy-3,16-dicarbonyl and 3β,5α-dihydroxy-6,16-dicarbonyl moieties were synthesized and confirmed by NMR spectroscopy. Novel and starting compounds were evaluated for their potential cytotoxicity in vitro against seven human cancer cell lines (MCF-7, MDA-MB-231, PC3, HeLa, HT-29, A549 and CEM) and one human noncancerous cell line (MRC-5). The most sensitive cell line was MDA-MB-231 derived from female reproductive tissue, wherein all compounds showed moderate to strong cytotoxic activity. Also, new compound with 5β,6β-epoxy-3,16-dicarbonyl moieties showed strong cytotoxic activity against colon adenocarcinoma (HT-29). In this work, in silico ADME properties of novel compounds were assessed by comparing calculated molecular properties with Lipinski, Veber, Egan, Ghose and Muegge criteria. The synthesis and structure elucidation of new oxygen-containing androstane derivatives was reported. New derivatives were tested for their in silico ADME properties and cytotoxicity against different human cancer cell lines.

Essential oil from leaves of Conobea scoparioides (Cham. & Schltdl.) Benth. (Plantaginaceae) causes cell death in HepG2 cells and inhibits tumor development in a xenograft model

Conobea scoparioides (Cham. & Schltdl.) Benth. (syn. Sphaerotheca scoparioides Cham. & Schldtl.) (Plantaginaceae), popularly known as "pataqueira", "vassourinha-do-brejo" and/or “hierba-de-sapo”, is a popular medicinal plant used to treat leishmaniasis, pain and beriberi. In addition, inhibition of cell adhesion, antioxidant, cytotoxic and leishmanicidal activities of compounds or fractions of C. scoparioides have been reported. In the present work, chemical constituents and in vitro and in vivo anti-liver cancer potential of essential oil (EO) from leaves of C. scoparioides were investigated using human hepatocellular carcinoma HepG2 cells as a cell model. EO was obtained by hydrodistillation using a Clevenger-type apparatus and characterized by GC–MS and GC–FID. The in vitro cytotoxic effect was evaluated on three human cancer cell lines (MCF-7, HepG2 and HCT116) and one human non-cancerous cell line (MRC-5) using the Alamar blue assay. Phosphatidylserine externalization and cell cycle distribution were quantified in HepG2 cells by flow cytometry after 48 h incubation. The effectiveness of EO in anti-liver cancer model was studied with HepG2 cells grafted on C.B. 17 SCID mice. The main constituents of EO were thymol methyl ether (62 %), thymol (16 %) and α-phellandrene (14 %). EO displayed an in vitro cytotoxic effect against all human cancer cell lines and caused externalization of phosphatidylserine and DNA fragmentation in HepG2 cells, suggesting induction of apoptotic-like cell death. In vivo tumor mass inhibition of 36.7 and 55.8 % was observed for treatment with EO at doses of 40 and 80 mg/kg, respectively. These results indicate in vitro and in vivo anti-liver cancer potential of EO from leaves of C. scoparioides.

Arene-Ruthenium(II) Complexes Containing 11H-Indeno[1,2-b]quinoxalin-11-one Derivatives and Tryptanthrin-6-oxime: Synthesis, Characterization, Cytotoxicity, and Catalytic Transfer Hydrogenation of Aryl Ketones.

A series of novel mono- and binuclear arene–ruthenium(II) complexes [(p-cym)Ru(L)Cl] containing 11H-indeno[1,2-b]quinoxalin-11-one derivatives or tryptanthrin-6-oxime were synthesized and characterized by X-ray crystallography, IR, NMR spectroscopy, cyclic voltammetry, and elemental analysis. Theoretical calculations invoking singlet state geometry optimization, solvation effects, and noncovalent interactions were done using density functional theory (DFT). DFT calculations were also applied to evaluate the electronic properties, and time-dependent DFT was applied to clarify experimental UV–vis results. Cytotoxicity for cancerous and noncancerous human cell lines was evaluated with cell viability MTT assay. Complexes demonstrated a moderate cytotoxic effect toward cancerous human cell line PANC-1. The catalytic activity of the complexes was evaluated in transfer hydrogenation of aryl ketones. All complexes exhibited good catalytic activity and functional group tolerance.

Total Synthesis and Stereochemical Assignment of Sunshinamide and Its Anticancer Activity.

Total synthesis of cyclodepsipeptide sunshinamide has been achieved for the first time using a convergent approach. The key features of this synthesis comprise Crimmins acetate aldol, Shiina esterification, amide coupling, macrolactamization, and an I2-mediated deprotection with concomitant disulfide-bridge formation. This synthetic study enabled the unambiguous determination of the stereochemistry of the unassigned stereocenter of the isolated sunshinamide. The cytotoxicity of sunshinamide and one of its analogues was evaluated against different cancerous and noncancerous human cell lines, which revealed their attractive and selective activities toward cancer cells at very low concentrations.

In vitro and in vivo growth inhibition of human acute promyelocytic leukemia HL-60 cells by Guatteria megalophylla Diels (Annonaceae) leaf essential oil

Guatteria megalophylla Diels (Annonaceae) is an 8−10 m tall tree that grows near streams and is widely spread throughout Colombian, Ecuadorian, Peruvian, Brazilian and Guianese Amazon rainforest. Herein, we investigated for the first time the chemical composition and in vitro and in vivo anti-leukemia potential of G. megalophylla leaf essential oil (EO) using human promyelocytic leukemia HL-60 cells as model. EO was obtained by a hydrodistillation clevenger-type apparatus and characterized quali- and quantitatively by GC–MS and GC–FID, respectively. In vitro cytotoxic potential of EO was evaluated in human cancer cell lines (HL-60, MCF-7 CAL27, HSC-3, HepG2 and HCT116) and in human non-cancer cell line (MRC-5) by Alamar blue method. Annexin V/propidium iodide staining, cell cycle distribution and reactive oxygen species (ROS) were assessed by flow cytometry for HL-60 cells treated with EO. In vivo efficacy of EO (50 and 100 mg/kg) was evaluated in C.B-17 SCID mice with HL-60 cell xenografts. Chemical composition analyses showed spathulenol, γ-muurolene, bicyclogermacrene, β-elemene and δ-elemene as main constituents of assayed sample. EO displayed in vitro cytotoxicity, including anti-leukemia effect with IC50 value of 12.51 μg/mL for HL-60 cells. EO treatment caused augment of phosphatidylserine externalization and DNA fragmentation without increasing of ROS in HL-60 cells. In vivo tumor mass inhibition rates of EO was 16.6–48.8 %. These data indicate anti-leukemia potential of G. megalophylla leaf EO.

Improvement of antimalarial activity of a 3-alkylpiridine alkaloid analog by replacing the pyridine ring to a thiazole-containing heterocycle: Mode of action, mutagenicity profile, and Caco-2 cell-based permeability

The development of new antimalarial drugs is urgent to overcome the spread of resistance to the current treatment. Herein we synthesized the compound 3, a hit-to‑lead optimization of a thiazole based on the most promising 3-alkylpyridine marine alkaloid analog. Compound 3 was tested against Plasmodium falciparum and has shown to be more potent than its precursor (IC50 values of 1.55 and 14.7 μM, respectively), with higher selectivity index (74.7) for noncancerous human cell line. This compound was not mutagenic and showed genotoxicity only at concentrations four-fold higher than its IC50. Compound 3 was tested in vivo against Plasmodium berghei NK65 strain and inhibited the development of parasite at 50 mg/kg. In silico and UV–vis approaches determined that compound 3 acts impairing hemozoin crystallization and confocal microscopy experiments corroborate these findings as the compound was capable of diminishing food vacuole acidity. The assay of uptake using human intestinal Caco-2 cell line showed that compound 3 is absorbed similarly to chloroquine, a standard antimalarial agent. Therefore, we present here compound 3 as a potent new lead antimalarial compound.

Investigating the Selectivity of Novel Chalcones for Human Cancer Cells Compared to Non‐Cancerous Human Cell Lines

We previously presented data on the anticancer activity of a small library of synthetic flavonoid derivatives against glioblastoma and breast cancer lines in addition to several other human cancer cell lines. This data suggested that the chalcone structural backbone afforded more potent anticancer activity compared to its flavanone counterpart. Using this data, we selected three lead compounds: RK6, RK7, and RK15, to screen for activity against non‐cancerous cells to test for selectivity. Here we present updated IC50 values of these three analogs against MCF7 breast adenocarcinoma cells in addition to the previously reported data on the A‐172 glioblastoma cell line. To determine the selectivity of these lead compounds, RK6, RK7, and RK15 were screened against two non‐cancerous human cell lines: normal human astrocytes (NHA) and normal human mammary epithelial cells (NHME).The activity of our lead compounds against A‐172 and MCF7 cells were assessed using the XTT cell viability assay to determine respective IC50 values. As reported previously, the IC50 values of our lead compounds in the A‐172 cell line were 20 μM, 22 μM, and 3 μM for RK6, RK7, and RK15 respectively. Updated IC50 values of the compounds in the MCF7 cell line were 19 μM, 99 μM, and 12 μM for RK6, RK7, and RK15.In order to evaluate the selectivity of the lead compounds for cancerous vs. non‐cancerous cells, we utilized the Vialight cell viability assay to screen the chalcones in NHA and NHME cells. In the NHA cells, the determined IC50 values of RK6, RK7, and RK15 were 47 μM, 52 μM, and >200 μM respectively. IC50 values were 60 μM, >200 μM, and >200 μM for the NHME cells treated with RK6, RK7, and RK15 respectively. This data was used to calculate selectivity indices for our lead compounds against A‐172 cells compared to NHA cells and MCF7 cells compared to NHME cells. For RK6, there was a 2.3 fold selectivity for A‐172 cells and a 3.1 fold selectivity for MCF7 cells compared to their non‐cancerous comparator cells. The selectivity index for RK7 showed a 2.3 fold selectivity for A‐172 compared to the NHA. In these instances, RK6 and RK7 appear to be somewhat selective for cancerous vs. non‐cancerous cell lines. Given the IC50 values >200 μM for RK7 in NHA cells and RK15 in NHA and NHME cells, exact selectivity indices could not be determined. However, in these occurrences, it would appear that the compounds demonstrated a high degree of selectivity for cancerous vs. non‐cancerous cells.Collectively, these results suggest that our lead chalcone compounds are at least somewhat selective for cancerous vs. non‐cancerous cells. Interestingly, the most potent compound in the A‐172 and MCF7 cells, RK15, demonstrated the highest degree of selectivity. This is intriguing given that recent trends in anticancer drug discovery favor compounds that are selective for cancer cells. These findings may provide some insights into the yet to be elucidated mechanisms of cell death by these novel chalcone derivatives, and will form the basis of future studies.Support or Funding InformationThis work was supported in part by an AFPE Gateway Scholarship for the first author.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

A screening of anti-breast cancer effects and antioxidant activity of twenty medicinal plants gathered from Chaharmahal va Bakhtyari province, Iran

Context: Breast cancer is one of the most prevalent cancers that causes substantial numbers of deaths among women, worldwide. Medicinal plants can be used for discovering new anti-breast cancer drugs. Aim: To investigate the antioxidant effects of twenty Iranian herbs and their anticancer effects against breast cancer cell lines (i.e. MDA-MB231 and MCF-7) compared with a non-cancerous human cell line (HDF). Methods: In this study, the plant samples were collected from different regions of Chaharmahal va Bakhtyari province in Iran and their hydroalcoholic (ethanol: water; 70:30) extracts prepared by maceration method. Antioxidant activity was investigated by DPPH with reference to butylated hydroxytoluene (BHT). Anticancer effects were investigated by MTT colorimetric assay. Results: Most of the plants examined in this study had higher antioxidant activity than that of BHT. Satureja bachtiarica (37.27 ± 1.56 µg/mL), Plantago lanceolata (43.19 ± 4.67 µg/mL), Parietaria judaica (45.34 ± 8.08 µg/mL), Stachys inflata (53.70 ± 1.80 µg/mL), and Euphorbia szovitsii (55.78 ± 1.37 µg/mL) inhibited the DPPH free radicals in the lower concentration compared to BHT (120.48 ± 1.42 µg/mL) and other plants. MTT assay showed that the lowest IC50s values were observed for E. microsciadia and E. szovitsii among the examined plants on both breast cancer cell lines. There was no significant relationship between anticancer effects and antioxidant activity of the plants (p>0.05). Conclusions: The examined plants might be considered as valuable resources of natural compounds that may possess anti-breast cancer properties.

Design, synthesis, antiproliferative activity, molecular docking and cell cycle analysis of some novel (morpholinosulfonyl) isatins with potential EGFR inhibitory activity

New series of 5-(morpholinosulfonyl) isatin derivatives were designed and synthesized. The new compounds were characterized on the basis of spectral and elemental analyses. They were examined for their cytotoxic effects using SRB assay on four cancer cell lines HepG2, HCT116, CACO and MCF-7 in addition to the non-cancerous human cell line. They were non cytotoxic towards the normal derived cell line (IC50 value > 130 μM). Compounds 3, 6, 10 and 11 showed IC50 values less than 10 μM on three of the tested cell lines HepG2, HCT116 and CACO. Compounds 2h, 5, and 7b showed IC50 values less than or nearly equal 10 μM on HepG2, CACO and HCT116 respectively. Compounds 3 and 6 revelaed IC50 values less than 12 μM on MCF7. These obtained IC50 values are comparable with that of doxrubicin as it has showed IC50 range from 4.5 to 8.28 μM on the tested cell lines. All these promising derivatives showed inhibitory activity against EGFR with IC50 values less than 2 μM. The most potent EGFR inhibitors 7b (IC50 = 46 nM) and 10 (IC50 = 23 nM) showed to cause cell cycle arrest at G2/M phase and induce apoptosis. Molecular docking studies also were simulated to put insight and make better understanding to their structural features.

Magnetic field direction differentially impacts the growth of different cell types

ABSTRACTMagnetic resonance imaging (MRI) machines have horizontal or upright static magnetic field (SMF) of 0.1–3 T (Tesla) at sites of patients and operators, but the biological effects of these SMFs still remain elusive. We examined 12 different cell lines, including 5 human solid tumor cell lines, 2 human leukemia cell lines and 4 human non-cancer cell lines, as well as the Chinese hamster ovary cell line. Permanent magnets were used to provide 0.2–1 T SMFs with different magnetic field directions. We found that an upward magnetic field of 0.2–1 T could effectively reduce the cell numbers of all human solid tumor cell lines we tested, but a downward magnetic field mostly had no statistically significant effect. However, the leukemia cells in suspension, which do not have shape-induced anisotropy, were inhibited by both upward and downward magnetic fields. In contrast, the cell numbers of most non-cancer cells were not affected by magnetic fields of all directions. Moreover, the upward magnetic field inhibited GIST-T1 tumor growth in nude mice by 19.3% (p < 0.05) while the downward magnetic field did not produce significant effect. In conclusion, although still lack of mechanistical insights, our results show that different magnetic field directions produce divergent effects on cancer cell numbers as well as tumor growth in mice. This not only verified the safety of SMF exposure related to current MRI machines but also revealed the possible antitumor potential of magnetic field with an upward direction.

Design, synthesis, and biological evaluation of novel combretastatin A-4 thio derivatives as microtubule targeting agents

A series of novel combretastatin A-4 (CA-4) thio derivatives containing different molecular cores, namely α-phenylcinnamic acids (core 1), (Z)-stilbenes (core 2), 4,5-disubstituted oxazoles (core 3), and 4,5-disubstituted N-methylimidazoles (core 4), as cis-restricted analogues were designed and synthesized. They were selected with the use of a parallel virtual screening protocol including the generation of a virtual combinatorial library based on an elaborated synthesis protocol of CA-4 analogues. The selected compounds were evaluated for antiproliferative activity against a panel of six human cancer cell lines (A431, HeLa, MCF7, MDA-MB-231, A549 and SKOV) and two human non-cancer cell lines (HaCaT and CCD39Lu). Moreover, the effect of the test compounds on the inhibition of tubulin polymerization in vitro was estimated. In the series studied here, oxazole-bridged analogues exhibited the most potent antiproliferative activity. Compounds 23a, 23e, and 23i efficiently inhibited tubulin polymerization with IC50 values of 0.86, 1.05, and 0.85 μM, respectively. Thio derivative 23i, when compared to its oxygen analogue 23j, showed a 5-fold higher inhibitory impact on tubulin polymerization. Compounds 23e and 23i, which showed both best cytotoxic and antitubulin activity, were further studied in terms of their effect on cell cycle distribution and proapoptotic activity. Compound 23e induced a statistically significant block of the cell cycle at the G2/M phase in A431, HaCaT, HeLa, MCF-7, MDA-MB-231, and SKOV-3 cells to an extent comparable to that observed in CA-4. In HeLa and SKOV-3 cells incubated with 23i, a concentration-dependent block of the G2/M phase was observed. The proapoptotic effect of 23e and 23i in A431, HaCaT, MCF-7, MDA-MB-231, and SKOV-3 was demonstrated with ELISA assay and double staining with Annexin V-FITC/PI. The results indicated that compound 23e and 23i may serve as novel lead compounds in research on more effective anticancer agents.

Identification of 7,8-Diacetoxy-3-Arylcoumarin Derivative as a Selective Cytotoxic and Apoptosis-inducing Agent in a Human Prostate Cancer Cell Line.

Coumarins are a member of the benzopyrone family of compounds with diverse and interesting pharmacological properties. In the present study, we report the in vitro cytotoxicity evaluation of 7,8-Diacetoxy-3-arylcoumarin derivatives (5a-h) in human prostate (PC-3) and breast (MDA-MB-231) cancer cell lines. The cytotoxic activity was evaluated using crystal violet dye-binding assay. Furthermore, the most active compound in vitro cytotoxic activity in human non-cancerous cell line and its effect on the cell-cycle phases, apoptosis proteins expression, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) production and Glutathione (GSH) level were performed. Among the eight compounds that were evaluated, 7,8-Diacetoxy-3-(4-methylsulfonyl phenyl)coumarin (5f) was the most active derivative with highest cytotoxic activity and selectivity against the PC-3 cell line vs. the non-cancerous WPE1-N22 cell line. The cytotoxic action of compound 5f in PC-3 cells is associated with the cell-cycle arrest at -G0/G1 phase, apoptosis, loss in mitochondrial membrane potential (MMP), induced reactive oxygen species (ROS) production and depletion of Glutathione (GSH) level. The result indicates that the presence of p-methylsulfonylphenyl group on compound 5f is critical in modulating selective cytotoxic activity and induction of apoptosis via the mitochondrial apoptotic signaling pathway that is independent of cytochrome c release.

Selective inhibition of endogenous antioxidants with Auranofin causes mitochondrial oxidative stress which can be countered by selenium supplementation

Auranofin is a thiol-reactive gold (I)-containing compound with potential asa chemotherapeutic. Auranofin has the capacity to selectively inhibit endogenous antioxidant enzymes thioredoxin reductase (TrxR) and glutathione peroxidase (GPx), resulting in oxidative stress and the initiation of a pro-apoptotic cascade. The effect of Auranofin exposure on TrxR and GPx, and the potential for cellular protection through selenium supplementation was examined in the non-cancerous human cell line Swan-71. Auranofin exposure resulted in a concentration dependent differential inhibition of selenoprotein antioxidants. Significant inhibition of TrxR was observed at 20nM Auranofin with inhibition of GPx from 10µM. Significant increases in reactive oxygen species (ROS) were associated with antioxidant inhibition at Auranofin concentrations of 100nM (TrxR inhibition) and 10µM (TrxR and GPx inhibition), respectively. Evaluation of mitochondrial respiration demonstrated significant reductions in routine and maximal respiration at both 100nM and 10μM Auranofin. Auranofin treatment at concentrations of 10μM and higher concentrations resulted in a ∼68% decrease in cellular viability and was associated with elevations in pro-apoptotic markers cytochrome c flux control factor (FCFc) at concentration of 100nM and mitochondrial Bax at 10μM. The supplementation of selenium (100nM) prior to treatment had a generalized protective affect through the restoration of antioxidant activity with a significant increase in TrxR and GPx activity, a significant reduction in ROS and associated improvement in mitochondrial respiration and cellular viability (10µM ∼48% increase). Selenium supplementation reduced the FCFc at low doses of Auranofin (<10μM) however no effect was noted on either FCFc or Bax at concentrations above 10μM. The inhibition of antioxidant systems in non-cancerous cells by Auranofin is strongly dose dependent, and this inhibition can be altered by selenium exposure. Therefore, Auranofin dose and the selenium status of patients are important considerations in the therapeutic use of Auranofin as an agent of chemosensitization.

Synthesis, Molecular Docking Study and in vitro Anticancer Activity of Tetrazole Linked Benzochromene Derivatives.

Globally, cancer is regarded as one of the biggest health concern in humans and animals and is one of the most terrifying diseases. Therefore, there is a necessity for the discovery, development and improvement of novel antitumor drug molecules which could efficiently prevent proliferative pathways and clonal expansion of cells. Heterocyclic compounds like benzochromene play a key role in the development of current pharmaceuticals, natural resources, agriculture products, analytical reagents and dyes. Therefore, anticancer drugs show increased resistance, it is essential to designing the novel structured heterocyclic moieties to create potential anticancer agents with promising biological applications. To synthesis a novel 1-(substitutedphenyl)-2-(1H-tetrazol-5-yl)-1H-benzo[f]chromene-3-amine derivatives for in vitro antitumour activity. The reaction of 3-amino-1-(substitutedphenyl)-1H-benzo[f]chromene-2-carbonitrile with sodium azide, ammonium chloride in dimethyl formamide solvent under reflux condition for 4 h afforded products (3a-k). The synthesized molecules were subjected to possible potential anti-tumour activity in vitro in four human cancer cell lines (MCF-7, Caco-2, HeLa and SKBR-3), and one human non-cancer cell line (HEK293), using the MTT cell viability assay. A novel series of products (3a-k) were synthesized with good yield and were identified with 1H NMR, 15N NMR, 13C NMR, FT-IR and HR-MS spectrum. The most potent compounds 3d, 3e, and 3f possessing the greatest cytotoxicity activity with IC50 values slightly higher (15-33 μM) than that of 5-Fluorouracil (10-17 μM), indicating their potential to be antitumor agents. The 3a, 3b, 3c, 3h, 3i and 3j compounds showed moderate activity. Additionally, a molecular docking analysis was conducted to predict the multi-drug resistance modulator behavior of synthesized compounds in the ATP binding site of P-glycoprotein. We synthesized and designated eleven novel derivatives of tetrazole linked benzochromenes (3a-k) and evaluated their anti-cancer activity. Additionally, the results from the docking studies were found to be in good agreement with the results from computational profiling.

Antiproliferative activity of Haematoxylum brasiletto H. Karst.

Background:Haematoxylum brasiletto is a tree that grows in Central America, commonly known as “Palo de Brasil,” which is used in the traditional medicine for the treatment of cancer and gastric ulcers.Objective:The aim of this study was to isolate the compounds responsible for antiproliferative activity of H. brasiletto.Materials and Methods:A bioassay-guided fractionation of ethanol extract of H. brasiletto was performed using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide cell proliferation assay to measure the antiproliferative activity on six human cancer cell lines (A549, LS180, HeLa, SiHa, MDA-MB-231, and NCI-H1299) and one human noncancer cell line (ARPE-19). The ethanol extract was partitioned with hexane, dichloromethane, and ethyl acetate. The active dichloromethane fraction was fractioned by silica-column chromatography, and active subfractions were separated using preparative-thin layer chromatography. The chemical structure of an isolated compound was elucidated with different chemical and spectroscopic methods.Results:The flavonoid brazilin (1) was isolated from the heartwood of H. brasiletto. The measurement of antiproliferative activity showed that brazilin can inhibit the growth of SiHa, MDA-MB-231, A549, and NCI-H1299 cell lines by 50% at doses of 44.3, 48.7, 45.4, and 48.7 μM, respectively. Furthermore, the flavonoid showed a high antiproliferative activity on LS 180 and HeLa with IC50 values of 62.2 and 71.9 μM, respectively. Brazilin also exhibited a high antiproliferative activity on the human noncancer cell line ARPE-19 with an IC50 value of 37.9 μM.Conclusions:Brazilin: (6aS, 11bR)-7,11b-Dihidro-6H-indeno[2,1-c] cromeno-3,6a, 9,10-tetrol was isolated; this compound demonstrated antiproliferative activity against several human cancer cell lines. This work demonstrated that brazilin, a flavonoid isolated and characterized of H. brasiletto, has antiproliferative activity against cancer cell lines.SUMMARY The flavonoid brazilin was isolated from the heartwood of H. brasilettoBrazilin is able to inhibit the growth of SiHa, MDA-MB-231, A549 and NCI- H1299 cancerous cell linesBrazilin exhibited a moderate antiproliferative activity on the human non-cancer cell line ARPE-19Brazilin demonstrated to have antiproliferative activity against human cancer cell lines and could be a potential source of anticancer agents. Abbreviations used: MTT: [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium]; FBS: Fetal bovine serum; TLC: Thin layer chromatography.

Inhibition of Ral GTPases Using a Stapled Peptide Approach

Aberrant Ras signaling drives numerous cancers, and drugs to inhibit this are urgently required. This compelling clinical need combined with recent innovations in drug discovery including the advent of biologic therapeutic agents, has propelled Ras back to the forefront of targeting efforts. Activated Ras has proved extremely difficult to target directly, and the focus has moved to the main downstream Ras-signaling pathways. In particular, the Ras-Raf and Ras-PI3K pathways have provided conspicuous enzyme therapeutic targets that were more accessible to conventional drug-discovery strategies. The Ras-RalGEF-Ral pathway is a more difficult challenge for traditional medicinal development, and there have, therefore, been few inhibitors reported that disrupt this axis. We have used our structure of a Ral-effector complex as a basis for the design and characterization of α-helical-stapled peptides that bind selectively to active, GTP-bound Ral proteins and that compete with downstream effector proteins. The peptides have been thoroughly characterized biophysically. Crucially, the lead peptide enters cells and is biologically active, inhibiting isoform-specific RalB-driven cellular processes. This, therefore, provides a starting point for therapeutic inhibition of the Ras-RalGEF-Ral pathway.

The cytotoxicity studies of water-soluble InP/ZnSe quantum dots

Biomedical applications require nanocrystals with a narrow emission spectra and low toxicity. One major challenge of using quantum dots (QDs) in biomedical studies has been to synthesize them in large quantities while retaining desirable optical properties. To date, no research has been carried out to scale up the synthesis of InP/ZnSe nanocrystals. In this regard we synthesized InP/ZnSe nanocrystals using lower volumes and masses and scaled up the synthesis while retaining their molar ratios. The properties of the products obtained in small scale and scaled up syntheses were compared in regard to changes in particle size, emission wavelength and the trend of fluorescence of the aliquots. The particle size for the small scale reaction was determined to be 4.18 nm. When the synthesis was scaled up by a factor of 2, 4 and 6, the sizes were found to increase to 4.31, 4.13 and 4.37 nm, respectively. We also demonstrated the ability to tune the emission wavelength by sorting the particles in the crude product to different sizes. The size sorting process gave QDs with varied emission wavelengths and also narrow emission spectra. We further demonstrated a facile method for their water solubility as well as suitability for various biological applications. The toxicity of the synthesized InP/ZnSe nanocrystals was investigated. The cytotoxicity studies were carried out using two different types of non-cancerous human cell lines, namely KMST6 and MCF-12A, which clearly showed that the nanocrystals have low toxicity and are suitable for biological applications.

Synthesis, characterization and biological evaluation of novel Ru(II)–arene complexes containing intercalating ligands

Three new ruthenium(II)–arene complexes, namely [(η6-p-cymene)Ru(Me2dppz)Cl]PF6 (1), [(η6-benzene)Ru(Me2dppz)Cl]PF6 (2) and [(η6-p-cymene)Ru(aip)Cl]PF6 (3) (Me2dppz=11,12-dimethyldipyrido[3,2-a:2′,3′-c]phenazine; aip=2-(9-anthryl)-1H-imidazo[4,5-f] [1,10] phenanthroline) have been synthesized and characterized using different spectroscopic techniques including elemental analysis. The complexes were found to be well soluble and stable in DMSO. The biological activity of the three complexes was tested in three different human cancer cell lines (A549, MDA-MB-231 and HeLa) and in one human non-cancerous cell line (MRC-5). Complexes 1 and 3, carrying η6-p-cymene as the arene ligand, were shown to be toxic in all cell lines in the low micromolar/subnanomolar range, with complex 1 being the most cytotoxic complex of the series. Flow cytometry analysis revealed that complex 1 caused concentration- and time-dependent arrest of the cell cycle in G2-M and S phases in HeLa cells. This event is followed by the accumulation of the sub-G1 DNA content after 48h, in levels higher than cisplatin and in the absence of phosphatidylserine externalization. Fluorescent microscopy and acridine orange/ethidium bromide staining revealed that complex 1 induced both apoptotic and necrotic cell morphology characteristics. Drug-accumulation and DNA-binding studies performed by inductively coupled plasma mass spectrometry in HeLa cells showed that the total ruthenium uptake increased in a time- and concentration-dependent manner, and that complex 1 accumulated more efficiently than cisplatin at equimolar concentrations. The introduction of a Me2dppz ligand into the ruthenium(II)-p-cymene scaffold was found to allow the discovery of a strongly cytotoxic complex with significantly higher cellular uptake and DNA-binding properties than cisplatin.