Design, synthesis and biological evaluation of novel quinazoline derivatives as immune checkpoint inhibitors.

In this work, we report 14 novel quinazoline derivatives as immune checkpoint inhibitors, IDO1 and PD-L1. The antitumor screening of synthesized compounds on ovarian cancer cells indicated that compound V-d and V-l showed the most activity with IC50 values of about 5 µM. Intriguingly, compound V-d emerges as a stand out, triggering cell death through caspase-dependent and caspase-independent manners. More importantly, V-d presents its ability to hinder tumor sphere formation and re-sensitized cisplatin-resistant A2780 cells to cisplatin treatment. These findings suggest that compound V-d emerges as a promising lead candidate for the future development of immuno anticancer agents.

Triptan use in elderly over 65 years and the risk of hospitalization for serious vascular events.

BACKGROUND: Several studies have focused on the use of triptan and the risk of acute vascular events but the existence of such association is still debated and has never been quantified in patients over 65 years. To assess whether triptan use among older is associated with an increased risk of hospitalization for acute vascular events. METHODS: A propensity score-matched cohort study was designed using the French national health insurance database linked to hospital stays. Patients aged ≥ 65 years, newly treated by triptans between 2011 and 2014, were included… The primary event was hospitalization for an acute ischemic vascular event within de 90 days following triptan initiation. Association with triptan exposure was investigated through cox regression model, considering exposure at inclusion, and with exposure as a time-varying variable A case-crossover (CCO) and a self-controlled case series (SCCS) analyses were also conducted to address potential residual confounding. RESULTS: The cohort included 24, 774 triptan users and 99 096 propensity matched controls (mean (SD) age: 71 years (5.9), 74% of women). Within 90 days after cohort entry, 163 events were observed in the triptan group, and 523 in the control group (0.66% vs. 0.53%, adjusted hazard ratio (aHR) exposed/not exposed 1.25 95%CI [1.05-1.49]; aHR time-varying 8.74 [5.21-14.66]). The association was significant (CCO) for all events (adjusted odds ratio (aOR1.63 [1.22-2.19]) with a more consistent association with cerebral events (aOR 2.14 [1.26-3.63]). The relative incidence (RI) for all events was 2.13 [1.76-2.58] in the SCCS, for cardiac (RI: 1.67 [1.23-2.27]) and for cerebral events (RI: 3.20, [2.30-4.45]). CONCLUSION: The incidence of acute vascular events was low among triptan users. We found that triptan use among older may be associated with a low increased risk for acute vascular events, which may be more marked for cerebral events such as stroke, than for cardiac events.

Design, synthesis and evaluation the bioactivities of novel 1,3-dimethyl-6-amino-1H-indazole derivatives as anticancer agents.

Indoleamine 2,3-dioxygenase (IDO1) is a heme-containing enzyme mainly responsible for the metabolism of tryptophan to kynurenine. To date, the IDO1 inhibitors have been developed intensively for the re-activation of the anticancer immune response. In this report, we designed, and synthesized novel 1,3-dimethyl-6-amino indazole derivatives as IDO1 inhibitors based on the structure of IDO1 active site. We further examined their anticancer activity on hypopharyngeal carcinoma cells (FaDu), squamous cell carcinoma of the oral tongue (YD-15), breast cancer cells (MCF7), and human dental pulp stem cells (HDPSC). Of them, compound N-(4-bromobenzyl)-1,3-dimethyl-1H-indazol-6-amine (7) remarkably suppressed IDO1 expression in a concentration - dependent manner. In addition, 7 was the most potential anticancer compound with inducing apoptosis activity as well as selectively activated extracellular signal-regulated kinases (ERK) in mitogen-activated protein kinase (MAPK) pathways on FaDu cells. Finally, compound 7 suppressed cell mobility in wound healing assay with the reduced expression of matrix metalloproteinase MMP9. Taken together, we believe that 7 is the most promising compound, which may be applied to treatment of hypopharyngeal carcinoma.

Establishment of a method to expose and measure pollution in excised porcine skin with electron paramagnetic resonance spectroscopy.

Health problems associated with the amount of air pollutants are increasing worldwide. Pollution damages not only the lungs; it also has an impact on skin health and is co-responsible for the development of skin diseases. Anti-pollution products are on the rise in the cosmetic market but so far, there is no established method to directly assess the impact of pollution on the skin and to test the efficacy of anti-pollution products. To address this problem, two different chambers were developed for the reproducible exposure to realistic air pollutant concentrations. One chamber for the exclusive use of excised skin and hair samples, the second chamber for ex vivo and in vivo measurements. Measurements of nicotine next to the investigated skin area allow conclusions to be drawn on the particle concentration to which the skin is exposed. Electron paramagnetic resonance spectroscopy, which enables the detection of free radicals in different systems, was applied to assess the hazard potential of pollution in the skin. A direct proof of the formation of free radicals in the skin by the model pollutant cigarette smoke could be demonstrated. An additional application of UV irradiation even increased the formation of free radicals in the skin seven-fold (sum parameter). Depending on the question of interest, the use of different spin probes allows various assessments of the radical formation in skin: the amount of radicals but also the antioxidant status of the microenvironment can be estimated. Using two exposure chambers, the direct formation of oxidative stress by cigarette smoke on ex vivo skin, with and without additional UV exposure, could be reproducibly examined. This measurement method is promising for the assessment of anti-pollution products and could allow a direct causal connection between pollutant, effect on the skin and the protective function of skin care products.

Flavonoids from the peels of Citrus unshiu Markov. and their inhibitory effects on RANKL-induced osteoclastogenesis through the downregulation of c-Fos signaling in vitro.

Phytochemical investigation of Citrus unshiu peels led to the isolation of eight new flavonols (7-9, 11-15) and sixteen known compounds (1-6, 10, 16-24). Their structures were elucidated using spectroscopic analysis (1D, 2D NMR, and HR-MS). Besides, all isolated compounds (1-24) were evaluated for their inhibitory effects on receptor activator of RANKL-induced osteoclastogenesis in BMMs. Among them, dimethylmikanin (1), quercetogetin (2), 3,3',4',5,7,8-hexamethoxyflavone (3), 3-methoxynobiletin (4) showed a significant inhibitory effect on RANKL-induced osteoclast differentiation at a concentration of 10 µM. Moreover, 3-methoxynobiletin (4) suppressed RANKL-induced osteoclastogenesis by decreasing the number of osteoclasts and osteoclast actin-ring formation in a dose-dependent manner without causing any cytotoxic effects on BMMs. At the molecular level, 3-methoxynobiletin (4) inhibited RANKL-induced c-Fos expression and subsequently NFATc1 activation, as well as the expression of osteoclastogenesis-related marker genes c-Src and CtsK. These findings suggested that 3-methoxynobiletin (4) attenuated osteoclast differentiation by inhibiting RANKL-mediated c-Fos signaling and that it may have therapeutic potential for treating or preventing bone resorption-related diseases, such as osteoporosis.

Impact of the Astaxanthin, Betanin, and EGCG Compounds on Small Oligomers of Amyloid Aß40 Peptide.

There is experimental evidence that the astaxanthin, betanin, and epigallocatechin-3-gallate (EGCG) compounds slow down the aggregation kinetics and the toxicity of the amyloid-ß (Aß) peptide. How these inhibitors affect the self-assembly at the atomic level remains elusive. To address this issue, we have performed for each ligand atomistic replica exchange molecular dynamic (REMD) simulations in an explicit solvent of the Aß11-40 trimer from the U-shape conformation and MD simulations starting from Aß1-40 dimer and tetramer structures characterized by different intra- and interpeptide conformations. We find that the three ligands have similar binding free energies on small Aß40 oligomers but very distinct transient binding sites that will affect the aggregation of larger assemblies and fibril elongation of the Aß40 peptide.

New Acetohydrazides Incorporating 2-Oxoindoline and 4-Oxoquinazoline: Synthesis and Evaluation of Cytotoxicity and Caspase Activation Activity.

In our search for new small molecules activating procaspase-3, we have designed and synthesized a series of new acetohydrazides incorporating both 2-oxoindoline and 4-oxoquinazoline scaffolds. Biological evaluation showed that a number of these acetohydrazides were comparably or even more cytotoxic against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer) in comparison to PAC-1, a first procaspase-3 activating compound, which was used as a positive control. One of those new compounds, 2-(6-chloro-4-oxoquinazolin-3(4H)-yl)-N'-[(3Z)-5-methyl-2-oxo-1,2-dihydro-3H-indol-3-ylidene]acetohydrazide activated the caspase-3 activity in U937 human lymphoma cells by 5-fold higher than the untreated control. Three of the new compounds significantly induced necrosis and apoptosis in U937 cells.

3-Hydroxyolean-12-en-27-oic Acids Inhibit RANKL-Induced Osteoclastogenesis in Vitro and Inflammation-Induced Bone Loss in Vivo.

Olean-12-en-27-oic acids possess a variety of pharmacological effects. However, their effects and underlying mechanisms on osteoclastogenesis remain unclear. This study aimed to investigate the anti-osteoclastogenic effects of five olean-12-en-27-oic acid derivatives including 3α,23-isopropylidenedioxyolean-12-en-27-oic acid (AR-1), 3-oxoolean-12-en-27-oic acid (AR-2), 3α-hydroxyolean-12-en-27-oic acid (AR-3), 23-hydroxy-3-oxoolean-12-en-27-oic acid (AR-4), and aceriphyllic acid A (AR-5). Among the five olean-12-en-27-oic acid derivatives, 3-hydroxyolean-12-en-27-oic acid derivatives, AR-3 and AR-5, significantly inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced mature osteoclast formation by reducing the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, F-actin ring formation, and mineral resorption activity. AR-3 and AR-5 decreased RANKL-induced expression levels of osteoclast-specific marker genes such as c-Src, TRAP, and cathepsin K (CtsK) as well as c-Fos and nuclear factor of activated T cells cytoplasmic 1 (NFATc1). Mice treated with either AR-3 or AR-5 showed significant protection of the mice from lipopolysaccharide (LPS)-induced bone destruction and osteoclast formation. In particular, AR-5 suppressed RANKL-induced phosphorylation of JNK and ERK mitogen-activated protein kinases (MAPKs). The results suggest that AR-3 and AR-5 attenuate osteoclast formation in vitro and in vivo by suppressing RANKL-mediated MAPKs and NFATc1 signaling pathways and could potentially be lead compounds for the prevention or treatment of osteolytic bone diseases.

Structure-activity relationship of leucyladenylate sulfamate analogues as leucyl-tRNA synthetase (LRS)-targeting inhibitors of Mammalian target of rapamycin complex 1 (mTORC1).

Leucyl-tRNA synthetase (LRS) plays an important role in amino acid-dependent mTORC1 signaling, which is known to be associated with cellular metabolism and proliferation. Therefore, LRS-targeting small molecules that can suppress mTORC1 activation may provide an alternative strategy to current anticancer therapy. In this work, we developed a library of leucyladenylate sulfate analogues by extensively modifying three different pharmacophoric regions comprising adenine, ribose and leucine. Several effective compounds were identified by cell-based mTORC1 activation assays and further tested for anticancer activity. The selected compounds mostly exhibited selective cytotoxicity toward five different cancer cell lines, supporting the hypothesis that the LRS-mediated mTORC1 pathway is a promising alternative target to current therapeutic approaches.

Novel 3,4-dihydro-4-oxoquinazoline-based acetohydrazides: Design, synthesis and evaluation of antitumor cytotoxicity and caspase activation activity.

In search for novel small molecules with antitumor cytotoxicity via activating procaspase-3, we have designed and synthesized three series of novel (E)-N'-benzylidene-4-oxoquinazolin-3(4H)-yl)acetohydrazides (5a-j, 6a-h, and 7a-h). On the phenyl ring ò the benzylidene part, three different substituents, including 2-OH-4-OCH3, 4-OCH3, and 4-N(CH3)2, were introduced, respectively. Biological evaluation showed that the acetohydrazides in series 5a-j, in which the phenyl ring of the benzylidene part was substituted by 2-OH-4-OCH3 substituent, exhibited potent cytotoxicity against three human cancer cell lines (SW620, colon; PC-3, prostate; NCI-H23, lung). Most of the compounds, in this series, especially compounds 5c, 5b and 5h, also significantly activated caspase-3 activity. Among these, compound 5c displayed 1.61-fold more potent than PAC-1 as caspase-3 activator. Cell cycle analysis showed that compounds 5b, 5c, and 5h significantly arrested the cell cycle in G1 phase. Further apoptotic studies also demonstrated compounds 5b, 5c, and 5h as strong apoptotic cell death inducers. The docking simulation studies showed that these compounds could activate procaspase via chelating Zn2+ ion bound to the allosteric site of the zymogen.

(E)-N'-Arylidene-2-(4-oxoquinazolin-4(3H)-yl) acetohydrazides: Synthesis and evaluation of antitumor cytotoxicity and caspase activation activity.

In our search for novel small molecules activating procaspase-3, we have designed and synthesised a series of novel acetohydrazides incorporating quinazolin-4(3H)-ones (5, 6, 7). Biological evaluation revealed eight compounds with significant cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). The most potent compound 5t displayed cytotoxicity up to 5-fold more potent than 5-FU. Analysis of structure-activity relationships showed that the introduction of different substituents at C-6 position on the quinazolin-4(3H)-4-one moiety, such as 6-chloro or 6-methoxy potentially increased the cytotoxicity of the compounds. In term of caspase activation activity, several compounds were found to exhibit potent effects, (e.g. compounds 7 b, 5n, and 5l). Especially, compound 7 b activated caspases activity by almost 200% in comparison to that of PAC-1. Further docking simulation also revealed that this compound potentially is a potent allosteric inhibitor of procaspase-3.

The Effects of 2',4'-Dihydroxy-6'-methoxy-3',5'- dimethylchalcone from Cleistocalyx operculatus Buds on Human Pancreatic Cancer Cell Lines.

2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC), a principal natural chalcone of Cleistocalyx operculatus buds, suppresses the growth of many types of cancer cells. However, the effects of this compound on pancreatic cancer cells have not been evaluated. In our experiments, we explored the effects of this chalcone on two human pancreatic cancer cell lines. A cell proliferation assay revealed that DMC exhibited concentration-dependent cytotoxicity against PANC-1 and MIA PACA2 cells, with IC50 values of 10.5 ± 0.8 and 12.2 ± 0.9 µM, respectively. Treatment of DMC led to the apoptosis of PANC-1 by caspase-3 activation as revealed by annexin-V/propidium iodide double-staining. Western blotting indicated that DMC induced proteolytic activation of caspase-3 and -9, degradation of caspase-3 substrate proteins (including poly[ADP-ribose] polymerase [PARP]), augmented bak protein level, while attenuating the expression of bcl-2 in PANC-1 cells. Taken together, our results provide experimental evidence to support that DMC may serve as a useful chemotherapeutic agent for control of human pancreatic cancer cells.

Structure-activity relationship investigation of Phe-Arg mimetic region of human glutaminyl cyclase inhibitors.

Glutamyl cyclase (QC) is a promising therapeutic target because of its involvement in the pathogenesis of Alzheimer's disease. In this study, we developed novel QC inhibitors that contain 3-aminoalkyloxy-4-methoxyphenyl and 4-aminoalkyloxyphenyl groups to replace the previously developed pharmacophore. Several potent inhibitors were identified, showing IC50 values in a low nanomolar range, and were further studied for in vitro toxicity and in vivo activity. Among these, inhibitors 51 and 53 displayed the most potent AßN3pE-40-lowering effects in in vivo acute model with reasonable BBB penetration, without showing cytotoxicity and hERG inhibition. The molecular modeling analysis of 53 indicated that the salt bridge interaction and the hydrogen bonding in the active site provided a high potency. Given the potent activity and favorable BBB penetration with low cytotoxicity, we believe that compound 53 may serve as a potential candidate for anti-Alzheimer's agents.

Potent human glutaminyl cyclase inhibitors as potential anti-Alzheimer's agents: Structure-activity relationship study of Arg-mimetic region.

Pyroglutamate-modified amyloid ß peptides (pGlu-Aß) are highly neurotoxic and promote the formation of amyloid plaques. The pGlu-Aß peptides are generated by glutaminyl cyclase (QC), and recent clinical studies indicate that QC represents an alternative therapeutic target to treat Alzheimer's disease (AD). We have previously developed a series of QC inhibitors with an extended pharmacophoric scaffold, termed the Arg-mimetic D-region. In the present study, we focused on the structure activity relationship (SAR) of analogues with modifications in the D-region and evaluated their biological activity. Most compounds in this series exhibited potent activity in vitro, and our SAR analysis and the molecular docking studies identified compound 202 as a potential candidate because it forms an additional hydrophobic interaction in the hQC active site. Overall, our study provides valuable insights into the Arg-mimetic pharmacophore that will guide the design of novel QC inhibitors as potential treatments for AD.

N'-[(E)-Arylidene]-2-(2,3-dihydro-3-oxo-4H-1,4-benzoxazin-4-yl)-acetohydrazides: Synthesis and Evaluation of Caspase Activation Activity and Cytotoxicity.

In our search for novel small cytotoxic molecules potentially activating procaspase-3, we have designed and synthesized a series of novel N'-[(E)-arylidene]-2-(2,3-dihydro-3-oxo-4H-1,4-benzoxazin-4-yl)acetohydrazides (5, 6). Biological evaluation revealed that seven compounds, including 5h, 5j, 5k, 5l, 5n, 6a, and 6b, exhibited moderate to strong cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). Among these compounds, two most cytotoxic compounds (5h and 5j) displayed from 3- up to 10-fold higher potency than PAC-1 and 5-FU in three cancer cell lines tested. Three compounds 5j, 5k, and 5n were also found to display better caspases activation activity in comparison to PAC-1. Especially, compound 5k activated the level of caspases activity by 200% higher than that of PAC-1. From this study, three compounds 5j, 5k, and 5n could be considered as potential leads for further design and development of caspase activators and anticancer agents.

Discovery of simplified leucyladenylate sulfamates as novel leucyl-tRNA synthetase (LRS)-targeted mammalian target of rapamycin complex 1 (mTORC1) inhibitors.

Leucyl-tRNA synthetase (LRS) has been reported to be a possible mediator of intracellular amino acids signaling to mTORC1. Given that mTORC1 is associated with cell proliferation and tumorigenesis, the LRS-mediated mTORC1 pathway may offer an alternative strategy in anticancer therapy. In this study, we developed a series of simplified analogues of leucyladenylate sulfamate (1) as LRS-targeted mTORC1 inhibitors. We replaced the adenylate group with a N-(3,4-dimethoxybenzyl)benzenesulfonamide (2a) or a N-(2-phenoxyethyl)benzenesulfonamide groups (2b) that can maintain specific binding, but has more favorable physicochemical properties such as reduced polarity and asymmetric centers. Among these simplified analogues, compound 16 and its constrained analogue 22 effectively inhibited S6K phosphorylation in a dose-dependent manner and exhibited cancer cell specific cytotoxicity against six different types of cancer cells. This result supports that LRS is a viable target for novel anticancer therapy.

Alkaloids from Piper nigrum Exhibit Antiinflammatory Activity via Activating the Nrf2/HO-1 Pathway.

In the present study, ten alkaloids, namely chabamide (1), pellitorine (2), retrofractamide A (3), pyrroperine (4), isopiperolein B (5), piperamide C9:1 (8E) (6), 6,7-dehydrobrachyamide B (7), 4,5-dihydropiperine (8), dehydropipernonaline (9), and piperine (10), were isolated from the fruits of Piper nigrum. Among these, chabamide (1), pellitorine (2), retrofractamide A (3), isopiperolein B (5), and 6,7-dehydrobrachyamide B (7) exhibited significant inhibitory activity on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells, with IC50 values of 6.8, 14.5, 30.2, 23.7, and 38.5 µM, respectively. Furthermore, compound 1 inhibited lipopolysaccharide-induced NO production in bone marrow-derived macrophages with IC50 value of 9.5 µM. Consistent with NO inhibition, treatment of RAW264.7 cells with chabamide (1), pellitorine (2), and 6,7-dehydrobrachyamide B (7) suppressed expression of inducible NO synthase and cyclooxygenase-2. Chabamide (1), pellitorine (2), and 6,7-dehydrobrachyamide B (7) induced heme-oxygenase-1 expression at the transcriptional level. In addition, compound 1 induced the nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) and upregulated the expression of Nrf2 target genes, NAD(P)H:quinone oxidoreductase 1 and γ-glutamyl cysteine synthetase catalytic subunit, in a concentration-dependent manner in RAW264.7 cells. These findings suggest that chabamide (1) from P. nigrum exert antiinflammatory effects via the activation of the Nrf2/heme-oxygenase-1 pathway; hence, it might be a promising candidate for the treatment of inflammatory diseases. Copyright © 2017 John Wiley & Sons, Ltd.

Inhibitory effects of compounds from Styrax obassia on NO production.

Two new benzofurans, 2-(3,4-dimethoxyphenyl)-5-(1,3-dihydroxypropyl)-7-methoxybenzofuran (1) and 2-(3,4-methylenedioxyphenyl)-5-(3-hydroxymethyletoxy-1-hydroxypropyl)-7-methoxybenzofuran (2), a new triterpene, 3ß, 6ß, 21ß-trihydroxyolean-12-ene (3), and eleven known compounds were isolated from the stem bark of Styrax obassia. The structures of the isolated compounds were established by extensive spectroscopic analyses, including 1D and 2D NMR and HRMS. Their anti-inflammatory activities were evaluated against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages. Compound 1 was shown to reduce LPS-induced iNOS expression in a dose-dependent manner. In addition, pretreating cells with 1 significantly suppressed their LPS-induced expression of COX-2 protein.

α-Substituted 2-(3-fluoro-4-methylsulfonamidophenyl)acetamides as potent TRPV1 antagonists.

A series of α-substituted acetamide derivatives of previously reported 2-(3-fluoro-4-methylsulfonamidophenyl)propanamide leads (1, 2) were investigated for antagonism of hTRPV1 activation by capsaicin. Compound 34, which possesses an α-m-tolyl substituent, showed highly potent and selective antagonism of capsaicin with Ki(CAP)=0.1 nM. It thus reflected a 3-fold improvement in potency over parent 1. Docking analysis using our homology model indicated that the high potency of 34 might be attributed to a specific hydrophobic interaction of the m-tolyl group with the receptor.

α-Methylated simplified resiniferatoxin (sRTX) thiourea analogues as potent and stereospecific TRPV1 antagonists.

A series of α-methylated analogues of the potent sRTX thiourea antagonists were investigated as rTRPV1 ligands in order to examine the effect of α-methylation on receptor activity. The SAR analysis indicated that activity was stereospecific with the (R)-configuration of the newly formed chiral center providing high binding affinity and potent antagonism while the configuration of the C-region was not significant.