Linderapyrone analogue LPD-01 as a cancer treatment agent by targeting importin7.

The Wnt/ß-catenin signaling pathway plays important roles in several cancer cells, including cell proliferation and development. We previously succeeded in synthesizing a small molecule compound inhibiting the Wnt/ß-catenin signaling pathway, named LPD-01 (1), and 1 inhibited the growth of human colorectal cancer (HT-29) cells. In this study, we revealed that 1 inhibits the growth of HT-29 cells stronger than that of another human colorectal cancer (SW480) cells. Therefore, we have attempted to identify the target proteins of 1 in HT-29 cells. Firstly, we investigated the effect on the expression levels of the Wnt/ß-catenin signaling pathway-related proteins. As a result, 1 inhibited the expression of target proteins of Wnt/ß-catenin signaling pathway (c-Myc and Survivin) and their genes, whereas the amount of transcriptional co-activator (ß-catenin) was not decreased, suggesting that 1 inhibited the Wnt/ß-catenin signaling pathway without affecting ß-catenin. Next, we investigated the target proteins of 1 using magnetic FG beads. Chemical pull-down assay combined with mass spectrometry suggested that 1 directly binds to importin7. As expected, 1 inhibited the nuclear translocation of importin7 cargoes such as Smad2 and Smad3 in TGF-ß-stimulated HT-29 cells. In addition, the knockdown of importin7 by siRNA reduced the expression of target genes of Wnt/ß-catenin signaling pathway. These results suggest that importin7 is one of the target proteins of 1 for inhibition of the Wnt/ß-catenin signaling pathway.

Cytotoxic activities of alkaloid constituents from the climbing stems and rhizomes of Sinomenium acutum against cancer stem cells.

From the methanolic extract of the climbing stems and rhizomes of Sinomenium acutum, two new aporphine analogues, acutumalkaloids I and II, were isolated together with fifteen known compounds including lysicamine. The chemical structures of the isolated new compounds were elucidated based on chemical/physicochemical evidence such as NMR and MS spectra. For acutumalkaloids I and II, the absolute configurations were established by comparison of experimental and predicted electronic circular dichroism (ECD) data. We compared anti-proliferative activities of isolated compounds with reported naturally occurring Wnt/ß-catenin pathway inhibitor, nuciferine. Among the isolated compounds, we found lysicamine have anti-proliferative activity against both of HT-29 human colon cancer cell line and its cancer stem cells (CSCs). The IC50 values of lysicamine against non-CSCs and its CSCs were lower than that of nuciferine. In addition, the results of western blotting analysis suggested that lysicamine inhibited the expression of Wnt/ß-catenin pathway target protein such as survivin. These results suggested that lysicamine show cytotoxic activity via inhibition of Wnt/ß-catenin pathway.

Chemical Structures and Anti-proliferative Effects of Valeriana fauriei Constituents on Cancer Stem Cells.

We isolated the new sesquiterpenes, valerianaterpenes IV and V, and the new lignans valerianalignans I-III from the methanol extracts of the rhizomes and roots of Valeriana fauriei and elucidated their structures based on chemical and spectroscopic findings. The absolute configuration of valerianaterpene IV and valerianalignans I-III were established by comparing experimental and predicted electronic circular dichroism (ECD) data. Among the isolated compounds, valerianalignans I and II exerted anti-proliferative activity against human astrocytoma cells (U-251 MG) and their cancer stem cells (U-251 MG CSCs). Interestingly, valerianalignans I and II notably exerted anti-proliferative activities at lower concentrations against CSCs than non-CSCs, and the absolute configurations of these compounds affected their activities.

Azaphilones produced by Penicillium maximae with their cell death-inducing activity on Adriamycin-treated cancer cell.

BACKGROUND: Heat shock proteins (Hsps) are overexpressed in several tumors and contribute to cell proliferation, metastasis, and anticancer drug resistance. Therefore, Hsp inhibitors have enhanced cytotoxicity as chemotherapeutic agents and may be effective with a reduced dosage for tumor therapy to avoid side effects. RESULTS: Four new azaphilones, maximazaphilones I-IV (1-4), and three known compounds (5-7) have been isolated from the airborne-derived fungus Penicillium maximae. Inhibitory effects of isolated compounds against induction of Hsp105 were evaluated by the luciferase assay system using Hsp105 promoter. In this assay, 2-4, 6, and 7 significantly inhibited hsp105 promoter activity without cytotoxicity. In addition, all isolated compounds except for 5 significantly induced the death of Adriamycin (ADR)-treated HeLa cells. Interestingly, 1-4, 6, and 7 didn't show anti-proliferative and cell death-inducing activity without ADR. CONCLUSION: This study revealed the chemical structures of maximazaphilones I-IV (1-4) and the potency of azaphilones may be useful for cancer treatment and reducing the dose of anticancer agents. In addition, one of the mechanisms of cell death-inducing activity for 2-4, 6, and 7 was suggested to be inhibitory effects of Hsp105 expression.

Anti-Proliferative Effects of Iridoids from Valeriana fauriei on Cancer Stem Cells.

We isolated seven new iridoid glucosides (valerianairidoids I-VII; 1-3, 6, 7, 9, and 12) and six known compounds from the methanol extract of the dried rhizomes and roots of Valeriana fauriei. Chemical and spectroscopic data were used to elucidate the chemical structures of the seven new iridoid glucosides, and their absolute configurations were determined by comparing their electronic circular dichroism (ECD) spectra with those determined experimentally. Aglycones 1a, 6a, and 9a, which were obtained by enzymatic hydrolysis of the isolated iridoid glucosides, exhibited anti-proliferative activities against cancer stem cells (CSCs) established by a sphere-formation assay using human breast cancer (MDA-MB-231) and human astrocytoma (U-251MG) cells. Interestingly, these iridoids selectively showed anti-proliferative activities against CSCs from MDA-MB-231 cells. These results suggest that the iridoids obtained in this study may have potency as a breast cancer treatment and as preventive agent via exterminating CSCs.

Comparison of the Concentration of Suspended Particles and Their Chemical Composition near the Ground Surface and Dust Extinction Coefficient by LIDAR.

In many epidemiological studies, the dust extinction coefficient measured by light detection and ranging (LIDAR) is used as an indicator of exposure to Asian dust. However, few reports on the relationship between the distribution of total suspended particles (TSPs) near the ground surface and the dust extinction coefficient exist. In this study, we examined the relationship between the concentrations of TSPs near the ground surface, substances indicative of mineral content, and air pollutants that may be transported with Asian dust and dust extinction coefficients in two regions: Imizu and Yurihama-Matsue, from March to May in 2011 and 2013. In both years, large dust extinction coefficients were observed in Imizu and Matsue on days when the concentrations of TSPs and mineral content indicators were high near the ground surface in Imizu and Yurihama, and Asian dust was expected to be highly suspended. In both regions, the concentrations of TSPs and mineral content indicators were significantly positively correlated with the dust extinction coefficient. The concentrations of all air pollutants analyzed were significantly positively correlated with the dust extinction coefficient in each region in 2013, but not in 2011. These results suggest that the dust extinction coefficient is a useful indicator of Asian dust near the ground surface; however, as harmful air pollutants occasionally move with Asian dust, it is necessary to monitor these pollutants near the ground surface when conducting an epidemiological study on the health effect of airborne particles.

Chemical structures and induction of cell death via heat shock protein inhibition of the prenylated phloroglucinol derivatives isolated from Hypericum erectum.

Four new prenylated phloroglucinol derivatives (+)-erectumol I (1a), (-)-erectumol I (1b), (-)-erectumol II (2a), and (+)-erectumol II (2b) were isolated from the methanol extracts of the whole plants of Hypericum erectum. These new compounds were isolated as a pair of enantiomers, respectively. The planar chemical structures and relative configurations of the new compounds were suggested by Cu-Kα X-ray diffraction analysis and been confirmed by high-resolution mass and 1D and 2D NMR spectroscopic data. The absolute configuration of the four new compounds were established by comparing the experimental and predicted electronic circular dichroism data. Isolated compounds 1b and 2b induced death of Adriamycin-treated HeLa cells. Their enantiomers 1a and 2a did not. In addition, the apparent mechanism of cell death of 1b was the inhibited expression of heat shock protein 105.

Construction of sulfur-containing compounds with anti-cancer stem cell activity using thioacrolein derived from garlic based on nature-inspired scaffolds.

Sulfur-containing compounds, such as cyclic compounds with a vinyl sulfane structure, exhibit a wide range of biological activities including anticancer activity. Therefore, the development of efficient strategies to synthesize such compounds is a remarkable achievement. We have developed a unique approach for the rapid and modular preparation of nature-inspired cyclic and acyclic sulfur-containing compounds using thioacrolein, a naturally occurring chemically unstable intermediate. We constructed thiopyranone derivatives through the regioselective sequential double Diels-Alder reaction of thioacrolein produced by allicin, a major component in garlic, and two molecules of silyl enol ether as the diene partner. The cytotoxicity toward cancer stem cells of the thiopyranones was equal to or higher than that of (Z)-ajoene (positive control) derived from garlic, and the thiopyranones had higher chemical stability than (Z)-ajoene.

Cell death-inducing activities via P-glycoprotein inhibition of the constituents isolated from fruits of Nandina domestica.

Two new pyrrole alkaloids methyl-E-mangolamide (1) and methyl-Z-mangolamide (2), four new megastigmane glycosides nandinamegastigmanes I-IV (3-6), and eight known compounds (7-14) were isolated from the methanol extract of the fruits of Nandina domestica. The structures of the new compounds were elucidated based on chemical and spectroscopic evidence. The absolute stereochemistry of nandinamegastigmane I (3) was established upon comparing the experimental and predicted electronic circular dichroism (ECD) data. Among the isolated compounds, 1 and 2 showed cell death-inducing activity on the Adriamycin-treated HeLa cells. In addition, one of the mechanisms for cell death-inducing activity of 1 and 2 was suggested as inhibition of P-glycoprotein.

Cell death-inducing activities via Hsp inhibition of the sesquiterpenes isolated from Valeriana fauriei.

Three new sesquiterpenes, valerianaterpenes I-III, and eight known compounds have been isolated from the methanol extract of the rhizomes and roots of Valeriana fauriei. The chemical structures of the three new sesquiterpenes were elucidated based on chemical and spectroscopic evidence. The absolute stereochemistry of valerianaterpene I was determined using X-ray crystallography. The cell death-inducing activity of isolated compounds alone or combination with Adriamycin (ADR) was observed by time-lapse cell imaging. Although the isolated compounds did not affect the number of mitotic entry cells and dead cells alone, kessyl glycol, kessyl glycol diacetate, and iso-teucladiol significantly increased the number of dead cells on ADR treated human cervical cancer cells. One of the mechanisms of cell death-inducing activity for the kessyl glycol acetate was suggested to be the inhibition of heat-shock protein 105 (Hsp105) expression level. This paper first deals with the naturally occurring compounds as Hsp105 inhibitor.

Linderapyrone: A Wnt signal inhibitor isolated from Lindera umbellata.

Linderapyrone, a Wnt signal inhibitor was isolated from the methanolic extract of the stems and twigs of Lindera umbellata together with epi-(-)-linderol A. Linderapyrone inhibited TCF/ß-catenin transcriptional activity that was evaluated using cell-based TOPFlash luciferase assay system. To evaluate the structure-activity relationship and mechanism, we synthesized linderapyrone and its derivatives from piperitone. As the results of further bioassay for synthesized compounds, we found both of pyrone and monoterpene moieties were necessary for inhibitory effect. cDNA microarray analysis in a linderapyrone derivative treated human colorectal cancer cells showed that this compound downregulates Wnt signaling pathway. Moreover, we successes to synthesize the derivative of linderapyrone that has stronger inhibitory effect than linderapyrone and ICG-001 (positive control).

Limonoids isolated from the Fortunella crassifolia and the Citrus junos with their cell death-inducing activity on Adriamycin-treated cancer cell.

From the fruits of Fortunella crassifolia and the peels of Citrus junos, two new limonoids, fortunellone and junosol were isolated together with three known compounds including nomilin. The chemical structures of the new compounds were elucidated based on chemical/physicochemical evidence. For fortunellone, the absolute configuration was established by comparison of experimental and predicted electronic circular dichroism (ECD) data. Fortunellon and nomilin significantly increased the number of dead cells on adriamycin (ADR)-treated human cervical cancer cells (HeLa). On the other hand, fortunellon and nomilin did not affects the number of dead cells alone. These results suggested that fortunellone and nomilin may have the potency as the chemotherapy enhancement agents.

Association of Protein and Endotoxin in Outdoor Air with Emergency Department Visits for Children and Adults with Asthma in Fukuoka, Japan.

We examined the association of biological components in airborne particles, i.e., proteins and endotoxins, in outdoor air with asthma exacerbation in the Fukuoka metropolitan area, Fukuoka, Japan. Data on emergency department (ED) visits for asthma in children (age, 0-14 years) and adults (age, 15-64 years) were collected at a medical center from December 2014 to November 2015. One hundred eighty-one children and 143 adults visited the ED for asthma, and the weekly number of ED visits in children increased in autumn, i.e., September (second week) to November (first week). Fine (aerodynamic diameter ≤2.5 µm) and coarse (≥2.5 µm) particles were collected for 3 or 4 weeks per month, and protein and endotoxin concentrations were analyzed. Protein was largely prevalent in fine particles (0.34-7.33 µg/m3), and concentrations were high in April, May, June, and October. In contrast, endotoxin was mainly included in coarse particles (0.0010-0.0246 EU/m3), and concentrations were high in September (third week), October (first, second, and fourth weeks), February (fourth week), and July (first week). The results of a Poisson regression analysis indicated that endotoxin (in fine and coarse particles alike) was a significant factor for ED visits related to asthma in children, even after adjusting for meteorological factors, i.e., temperature, relative humidity, and wind speed. However, there was no association between environmental factors and ED visits for asthma in adults. These results suggest that endotoxin in outdoor air is significantly associated with an increased risk of asthma exacerbation in children.

Development of a system for the detection of the inflammatory response induced by airborne fine particulate matter in rat tracheal epithelial cells.

Exposure to airborne particulate matter (PM) is related to the increased risk of several diseases, including chronic and allergic rhinitis. We have previously shown that atmospheric endotoxin level was positively associated with the number of emergency department visits for asthma even after adjusting for meteorological factors, suggestive of the significant association between atmospheric endotoxin level and asthma exacerbation. Whether atmospheric endotoxin level is related to inflammatory response induction is, however, unclear. Here, we established stable cell lines to determine the promoter activity of the genes encoding pro-inflammatory cytokines such as tumor necrosis factor alpha, interleukin 6 (IL6), and IL33 by transfection of each reporter plasmid into rat tracheal epithelial EGV-4 T cells. These cells could measure the inflammatory response induced by endotoxin treatment more easily, rapidly, and sensitively than the conventional system using immunodetection assays. Furthermore, we revealed a relationship between atmospheric endotoxin level and inflammatory response induction. Thus, the system established herein may serve as a promising tool to monitor inflammatory response induced upon PM exposure.

Development of a system for the detection of the inflammatory response induced by airborne fine particulate matter in rat tracheal epithelial cells.

Exposure to airborne particulate matter (PM) is related to the increased risk of several diseases, including chronic and allergic rhinitis. We have previously shown that atmospheric endotoxin level was positively associated with the number of emergency department visits for asthma even after adjusting for meteorological factors, suggestive of the significant association between atmospheric endotoxin level and asthma exacerbation. Whether atmospheric endotoxin level is related to inflammatory response induction is, however, unclear. Here, we established stable cell lines to determine the promoter activity of the genes encoding pro-inflammatory cytokines such as tumor necrosis factor alpha, interleukin 6 (IL6), and IL33 by transfection of each reporter plasmid into rat tracheal epithelial EGV-4 T cells. These cells could measure the inflammatory response induced by endotoxin treatment more easily, rapidly, and sensitively than the conventional system using immunodetection assays. Furthermore, we revealed a relationship between atmospheric endotoxin level and inflammatory response induction. Thus, the system established herein may serve as a promising tool to monitor inflammatory response induced upon PM exposure.

Cytotoxic activities of sesquiterpenoids from the aerial parts of Petasites japonicus against cancer stem cells.

From the methanolic extract of the aerial parts of Petasites japonicus, six new eremophilane-type sesquiterpenoids, petasitesterpenes I-VI were isolated together with eight known compounds including S-japonin and eremophilenolide. The chemical structures of the isolated new compounds were elucidated based on chemical/physicochemical evidence. For petasitesterpenes I and II, the absolute configurations were established by comparison of experimental and predicted electronic circular dichroism (ECD) data. Among the isolated compounds, petasitesterpenes I, II, VI, and S-japonin showed cytotoxic activity against both human astrocytoma U-251MG cancer cells (non-CSCs) and their cancer stem cells (CSCs) isolated by sphere formation. In addition, cytotoxic activities of these compounds against breast cancer MDA-MB-231 were evaluated, supporting that petasitesterpene II has more effective than other isolated compounds.

Similar polycyclic aromatic hydrocarbon and genotoxicity profiles of atmospheric particulate matter from cities on three different continents.

The extractable organic material (EOM) from atmospheric total suspended particles (TSP) contains several organic compounds including non-substituted polycyclic aromatic hydrocarbons (PAHs), alkyl-PAHs, and nitro-PAHs. These chemicals seem to be among the key drivers of TSP genotoxicity. We have shown previously that the mutagenic potencies of the EOM from Limeira, Stockholm, and Kyoto, cities with markedly different meteorological conditions and pollution sources are similar. Here we compare the profiles of non-substituted PAHs (27 congeners), alkyl-PAHs (15 congeners), and nitro-PAHs (7 congeners) from the same EOM samples from these cities. We also compared the genotoxicity profiles using comet and micronucleus assays in human bronchial epithelial cells. The profiles of PAHs, as well as the cytotoxic and genotoxic potencies when expressed in EOM, were quite similar among the studied cities. It seems that despite the differences in meteorological conditions and pollution sources of the cities, removal, mixing, and different atmospheric transformation processes may be contributing to the similarity of the PAHs composition and genotoxicity profiles. More studies are required to verify if this would be a general rule applicable to other cities. Although these profiles were similar for all three cities, the EOM concentration in the atmospheres is markedly different. Thus, the population of Limeira (∼10-fold more EOM/m3 than Stockholm and ∼6-fold more than Kyoto) is exposed to higher concentrations of genotoxic pollutants, and Kyoto's population is 1.5-fold more exposed than Stockholm's. Therefore, to reduce the risk of human exposure to TSP genotoxins, the volume of emissions needs to be reduced.

Isolation and structure elucidation of constituents of Citrus limon, Isodon japonicus, and Lansium domesticum as the cancer prevention agents.

In the course of our research to investigate the cancer prevention potency of natural products derived from plant materials, we isolated fifty-five compounds, including twenty-one new compounds from the peels of Citrus limon, aerial parts of Isodon japonicus, and leaves of Lansium domesticum. The chemical structures of the isolated compounds were elucidated by chemical/physicochemical evidence, and nuclear magnetic resonance spectroscopy and mass spectrometry results. Moreover, the absolute stereochemistry of the new compounds were elucidated by various techniques such as chemical synthesis, modified Mosher's method, Cu-Kα X-ray crystallographic analysis, and comparison of experimental and predicted electronic circular dichroism data. The antimutagenic effects of the isolated and structure-elucidated compounds against heterocyclic amines, 3-amino-1,4-dimethyl-5H-pyrido [4,3-b]indole (Trp-P-1) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), were evaluated by the Ames test and in vivo micronucleus test. In this review, we present the comprehensive results of the antimutagenic effects of the isolated natural products.

Chemical structures and cytotoxic activities of the constituents isolated from Hibiscus tiliaceus.

Five new cadinene-type sesquiterpenes, hibiscusterpenes I-V (1-5), and six known compounds (6-11) have been isolated from the methanol extract of the stems and the twigs of Hibiscus tiliaceus. The structures of the new compounds were elucidated based on chemical and spectroscopic evidence. The absolute stereochemistry of hibiscusterpene I (1) was determined using X-ray crystallography. For hibiscusterpene III (3), the absolute configuration was established upon comparison of the experimental and predicted electronic circular dichroism (ECD) data. Among the isolated compounds, hibiscone C (7) and syriacusin A (11) showed cytotoxic activity in HeLa cells. In addition, their cell death-inducing activity was observed using time-lapse cell imaging.

Relationship of Asian Dust Events with Atmospheric Endotoxin and Protein Levels in Sasebo and Kyoto, Japan, in Spring.

Asian dust events are caused by dust storms originating from deserts in Mongolia and northern China, and these events are observed in Japan, mainly in spring. To explore the effect of Asian dust events on atmospheric endotoxin and protein levels, we collected the total suspended particles (TSP) in the spring months (March, April, and May) of 2015 in Sasebo and Kyoto, Japan, and assessed the levels of biological elements at both locations. At both locations, the daily concentrations of TSP, water-soluble Ca2+ (an indicator mineral of soil in dust), endotoxins, and proteins were found to be high during and after Asian dust events recorded by the Japan Meteorological Agency. The concentration of Ca2+ showed a strong positive correlation with the concentrations of TSP and endotoxin, while the concentration of protein was moderately positively correlated with Ca2+ in both Sasebo and Kyoto. There were large concentrations of endotoxins, and the fluctuation ranges were higher in Sasebo than in Kyoto. In contrast, protein concentrations showed low levels of fluctuation, and no major differences were found in the concentration at each location.