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1.
Front Psychiatry ; 12: 596293, 2021.
Article in English | MEDLINE | ID: mdl-33716813

ABSTRACT

Background: Mental illness-related stigma represents a barrier to seeking and receiving appropriate mental health care. Mental health literacy (MHL) can improve mental health knowledge, decrease stigmatizing attitudes, and enhance help-seeking behavior. Starting from 2022, mental illness-related education is due to be introduced in high schools in Japan. For this current situation, we conducted a parallel group, randomized controlled trial to examine the effectiveness of MHL educational program for teachers. Methods: The educational program described in this study comprised a 50-min video lesson designed to improve teachers' MHL. All participants were schoolteachers and were assigned either to an educational group or a waitlist control group. The assessment was conducted for both groups twice: first at baseline and then at 1-h post-intervention. The outcome measures for this trial were changes in knowledge, attitudes, and intended behaviors. Results: The educational group showed a greater improvement in knowledge regarding mental health than did the control group. The program was not effective for decreasing stigma toward mental illness. However, the educational group showed an increased intention to assist students with depression. Limitations: No long-term follow-up was implemented, which means the persistence of the educational program's effect could not be determined. Further, we could not report whether the program induced a change in teachers' behaviors regarding providing support for their students. Conclusions: The short video-based MHL educational program could improve schoolteachers' MHL and increase their intention to assist students. These findings can help in the development of similar educational programs in countries/regions experiencing similar issues regarding mental health.

3.
Sci Rep ; 10(1): 16175, 2020 09 30.
Article in English | MEDLINE | ID: mdl-32999406

ABSTRACT

What we taste is affected by what we see, and that includes the colour, opacity, and shape of the food we consume. We report two experiments designed to investigate how the standard deviation (SD) of the luminance distribution of food images influences the perceived visual texture and the taste/flavour experience by using the latest Augmented Reality (AR) technology. We developed a novel AR system capable of modifying the luminance distribution of foods in real-time using dynamic image processing for simulating actual eating situations. Importantly, this form of dynamic image manipulation does not change the colour on the food (which has been studied extensively previously). Instead, the approach outlined here was used to change the SD of the luminance distribution of the food while keeping the chromaticity, the average luminance, and the skewness constant. We investigated the effects of changing the luminance SD distribution of Baumkuchen (a German baked cake) and tomato ketchup on visual perception, flavour expectations, and the ensuing taste experience. Participants looked at a piece of Baumkuchen (Experiment 1) or a spoonful of tomato ketchup (Experiment 2) having different luminance distributions and evaluated the taste on sampling the food. Manipulating the SD of the luminance distribution affected not only the expected taste/flavour of the food (e.g. expected moistness, wateriness and deliciousness), but also the actual taste properties on sampling the food itself. The novel food modification method and system outlined here can therefore potentially be used to control the taste/flavour of different foods crossmodally by means of modifying their appearance properties (specifically the SD of the luminance distribution while keeping other aspects of image statistics constant), and can do so in real time, without the need for food markers.


Subject(s)
Anticipation, Psychological/physiology , Lighting , Taste Perception/physiology , Taste/physiology , Visual Perception/physiology , Eating , Female , Food , Humans , Male , Young Adult
4.
Bioorg Med Chem Lett ; 30(16): 127352, 2020 08 15.
Article in English | MEDLINE | ID: mdl-32631550

ABSTRACT

Human pancreatic cancer is resistant to almost all conventional chemotherapeutic agents. It is known to proliferate aggressively within hypovascular tumor microenvironment by exhibiting remarkable tolerance to nutrition starvation,  a phenomenon termed as "austerity". Search for the new agents that eliminate the tolerance of cancer cells to nutrition starvation is a promising strategy in anticancer drug discovery. In this study, two new meroterpenoids named callistrilones O and P (1 and 2) together with eight known triterpenes (3-10) were isolated from the active dichloromethane extract of Callistemon citrinus leaves. The structure elucidation of the new compounds was achieved by HRFABMS, 1D, 2D NMR, and ECD quantum calculations. All isolated compounds were tested for their preferential cytotoxicity against PANC-1 human pancreatic cancer cells. Among these, callistrilone O (1) exhibited the most potent preferential cytotoxicity with a PC50 value of 0.3 nM, the strongest activity with over 2000 times potent than the positive control arctigenin. Callistrilone O (1) induced dramatic alterations in PANC-1 cell morphology leading to cell death under nutrient-deprived conditions. Compound 1 also inhibited PANC-1 cell migration and -PANC-1 colony formation under the nutrient-rich condition.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Myrtaceae/chemistry , Pancreatic Neoplasms/drug therapy , Terpenes/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Death/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Egypt , Humans , Molecular Structure , Pancreatic Neoplasms/pathology , Structure-Activity Relationship , Terpenes/chemistry , Terpenes/isolation & purification , Tumor Microenvironment/drug effects , Pancreatic Neoplasms
5.
J Nat Prod ; 83(7): 2221-2232, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32573227

ABSTRACT

Human pancreatic cancer cells display remarkable tolerance to nutrition starvation that help them to survive in a hypovascular tumor microenvironment, a phenomenon known as "austerity". The elucidation of agents countering this tolerance is an established antiausterity strategy in anticancer drug discovery. In this study, a Callistemon citrinus leaf extract inhibited the viability of PANC-1 human pancreatic cancer cells preferentially under nutrient-deprived medium (NDM) with a PC50 value of 7.4 µg/mL. Workup of this extract resulted in the isolation of three new meroterpenoids, callistrilones L-N (1-3), together with 14 known compounds (4-17). The structure elucidation of the new compounds was achieved by HRFABMS and by NMR and ECD spectroscopic analysis. The new compounds showed highly potent preferential cytotoxicity against PANC-1 cells with PC50 values ranging from 10 to 65 nM in NDM. Of these, callistrilone L (1) inhibited PANC-1 cell migration and colony formation in a normal nutrient-rich condition. Callistrilone L (1) also strongly suppressed the migration of PANC-1 cells in real time. Mechanistically, 1 was found to inhibit the Akt/mTOR and autophagy activation pathway. Callistrilone L (1) and related meroterpenoids are promising leads for anticancer drug development based on the antiausterity strategy used in this work.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Myrtaceae/chemistry , Pancreatic Neoplasms/pathology , Antineoplastic Agents, Phytogenic/chemistry , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Spectrum Analysis/methods
6.
Lung Cancer ; 140: 8-18, 2020 02.
Article in English | MEDLINE | ID: mdl-31838169

ABSTRACT

OBJECTIVES: To describe the treatment patterns and determine the effectiveness and safety of nivolumab treatment for non-small cell lung cancer (NSCLC) in real-world setting in Japan. MATERIALS AND METHODS: Japanese patients with NSCLC who received nivolumab were analyzed retrospectively. Patients who had started nivolumab treatment between April 2016 and December 2016 were enrolled. Information regarding patient demographics and clinical backgrounds, treatment patterns from diagnosis to post-nivolumab treatment, effectiveness and safety of nivolumab treatment and that of treatments just before and after nivolumab treatment, and programmed death-ligand 1 (PD-L1) expression status, if available, were collected. Factors associated with nivolumab effectiveness identified by univariate and multivariate analyses were further investigated for plotting Kaplan-Meier curves of epidermal growth factor receptor (EGFR) gene mutation status, PD-L1 expression status, and Eastern Cooperative Oncology Group performance status (ECOG PS). RESULTS: In this study, 901 NSCLC patients were enrolled. Nivolumab was used the most as a second line treatment with a median number of nivolumab doses of five. The median overall survival (OS) was 14.6 months, one-year survival rate was 54.3 %, and median progression-free survival (PFS) was 2.1 months. The objective response rate was 20.5 % and disease control rate was 57.4 %. According to multivariate analyses, better OS and PFS were associated with favorable ECOG PS and absence of liver metastasis. Better PFS was observed in patients without EGFR mutation and patients with smoking history. PFS and best overall response in PD-L1 expression subgroups were expression level-dependent. The overall incidence of irAEs was 45.8 %, and the incidence of adverse events of grade 3 or higher was 14.0 %. CONCLUSION: The real-world effectiveness and safety of nivolumab is consistent with that reported by previous clinical trials and other real-world data. Subgroup analysis showed that ECOG PS, EGFR mutation status, smoking status, and PD-L1 were associated with the effectiveness of nivolumab.


Subject(s)
Adenocarcinoma of Lung/drug therapy , Antineoplastic Agents, Immunological/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Squamous Cell/drug therapy , Lung Neoplasms/drug therapy , Nivolumab/therapeutic use , Adenocarcinoma of Lung/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Squamous Cell/pathology , Female , Follow-Up Studies , Humans , Japan , Lung Neoplasms/pathology , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate
7.
Bioorg Med Chem Lett ; 27(21): 4898-4903, 2017 11 01.
Article in English | MEDLINE | ID: mdl-28947153

ABSTRACT

The chloroform extract of the Japanese cypress Chamaecyparis obtusa was found to kill PANC-1 human pancreatic cancer cells preferentially in the nutrient-deprived medium without causing toxicity in the nutrient rich condition. Phytochemical investigation on this extract led to the isolation of a new sesquiterpene (1), together with the six sesquiterpenes (2-7) and a lignan (8). The isolated compounds were tested for their preferential cytotoxicity activity against five different human pancreatic cancer cell lines [PANC-1, MIA PaCa2, CAPAN-1, PSN-1, and KLM-1] by utilizing an antiausterity strategy. Among them, α-cadinol (2) was identified as the most active constituent. α-Cadinol (2) was found to inhibit the activation of Akt/mTOR pathway, and the hyperactivation of autophagy leading to preferential PANC-1 cell death during nutrient-starvation.


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Chamaecyparis/chemistry , Cyclodecanes/chemistry , Sesquiterpenes/chemistry , Terpenes/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/toxicity , Autophagy/drug effects , Cell Line, Tumor , Chamaecyparis/metabolism , Cyclodecanes/isolation & purification , Cyclodecanes/toxicity , Drug Evaluation, Preclinical , Drug Screening Assays, Antitumor , Humans , Magnetic Resonance Spectroscopy , Microscopy, Fluorescence , Molecular Conformation , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/metabolism , Sesquiterpenes/isolation & purification , Sesquiterpenes/toxicity , TOR Serine-Threonine Kinases/antagonists & inhibitors , TOR Serine-Threonine Kinases/metabolism , Terpenes/isolation & purification , Terpenes/toxicity
8.
Bioorg Med Chem Lett ; 27(9): 1967-1971, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28342587

ABSTRACT

From the chloroform extract of the leaves of Uvaria dac, four new highly-oxygenated cyclohexene derivatives named uvaridacols I-L (1-4) were isolated together with nine previously reported compounds (5-13). Their structures were determined based on the extensive NMR spectroscopic data and circular dichroism spectroscopic analysis. Among the new compounds, uvaridacol L (4) displayed strong preferential cytotoxicity in the nutrient deprived medium against five different tested pancreatic cancer cell lines, PANC-1 (PC50, 20.1µM), PSN-1 (PC50, 9.7µM), MIA PaCa-2 (PC50, 29.1µM), Capan-1 (73.0µM) and KLM-1 (25.9µM).


Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cyclohexenes/chemistry , Cyclohexenes/pharmacology , Oxygen/chemistry , Uvaria/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Cyclohexenes/isolation & purification , Drug Screening Assays, Antitumor , Humans , Pancreas/drug effects , Pancreatic Neoplasms/drug therapy , Plant Leaves/chemistry
9.
Nat Prod Commun ; 11(6): 723-4, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27534101

ABSTRACT

Phytochemical investigation of the CH2Cl2 extract of the Vietnamese medicinal plant Caesalpinia sappan Linn resulted in the isolation of a new cassane-type diterpene named tomocin I (1). Its chemical structure was determined by NMR spectroscopic and mass spectrometric analysis.


Subject(s)
Caesalpinia/chemistry , Plant Extracts/chemistry , Molecular Structure , Plant Extracts/isolation & purification , Seeds/chemistry
10.
Bioorg Med Chem Lett ; 26(5): 1471-4, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26832787

ABSTRACT

A series of functionalized coumarins were synthesized and evaluated for their capacity to inhibit the resistance to starvation of pancreatic cancer cells. This form of cytotoxicity, termed 'antiausterity' activity, was evaluated using a preferential cytotoxicity assay that compared cell survival in nutrient poor and nutrient rich conditions. Six of the seventeen compounds showed weak antiausterity activity against PANC-1. Compound 34 was active against PANC-1, MIA PaCa-2, and Capan-1 cancer cell lines. All of the compounds tested were simplified structural analogs of previously reported natural product leads. Six of the compounds, including 34, contain functionalized triazoles as novel potential bioisosteres of the side chain of the natural product angelmarin. Overall, the analogs were found to have low antiausterity activity relative to the corresponding natural products.


Subject(s)
Antineoplastic Agents, Phytogenic/chemical synthesis , Antineoplastic Agents, Phytogenic/pharmacology , Biological Products/pharmacology , Coumarins/chemical synthesis , Coumarins/pharmacology , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Antineoplastic Agents, Phytogenic/chemistry , Biological Products/chemical synthesis , Biological Products/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Coumarins/chemistry , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Structure-Activity Relationship
11.
Phytochemistry ; 122: 286-293, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26769396

ABSTRACT

Eight structurally diverse cassane diterpenes named tomocins A-H were isolated from the seed kernels of Vietnamese Caesalpinia sappan Linn. Their structures were determined by extensive NMR and CD spectroscopic analysis. Among the isolated compounds, tomocin A, phanginin A, F, and H exhibited mild preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrition-deprived condition without causing toxicity in normal nutrient-rich conditions.


Subject(s)
Caesalpinia/chemistry , Diterpenes/isolation & purification , Cell Line, Tumor , Diterpenes/chemistry , Diterpenes/pharmacology , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Pancreatic Neoplasms/drug therapy , Seeds/chemistry
12.
J Med Chem ; 58(15): 6093-113, 2015 Aug 13.
Article in English | MEDLINE | ID: mdl-26200813

ABSTRACT

An orally active dual CysLT1 and CysLT2 antagonist possessing a distinctive structure which consists of triple bond and dicarboxylic acid moieties is described. Gemilukast (ONO-6950) was generated via isomerization of the core indole and the incorporation of a triple bond into a lead compound. Gemilukast exhibited antagonist activities with IC50 values of 1.7 and 25 nM against human CysLT1 and human CysLT2, respectively, and potent efficacy at an oral dose of 0.1 mg/kg given 24 h before LTD4 challenge in a CysLT1-dependent guinea pig asthmatic model. In addition, gemilukast dose-dependently reduced LTC4-induced bronchoconstriction in both CysLT1- and CysLT2-dependent guinea pig asthmatic models, and it reduced antigen-induced constriction of isolated human bronchi. Gemilukast is currently being evaluated in phase II trials for the treatment of asthma.


Subject(s)
Asthma/drug therapy , Butyrates/pharmacology , Butyrates/therapeutic use , Indoles/pharmacology , Indoles/therapeutic use , Leukotriene Antagonists/pharmacology , Leukotriene Antagonists/therapeutic use , Receptors, Leukotriene/drug effects , Animals , Biological Availability , Dogs , Guinea Pigs , Humans , Leukotriene Antagonists/pharmacokinetics , Rats
13.
Chem Pharm Bull (Tokyo) ; 63(2): 122-5, 2015.
Article in English | MEDLINE | ID: mdl-25475833

ABSTRACT

An attempt to synthesize aglycone 1 derived from 2,3,5,4'-tetrahydroxystilbene-2-O-ß-glucoside (THSG) via the Wittig reaction and Mizoroki-Heck reaction is described. In the Wittig protocol, 2,3,5,4'-tetramethoxystilbene 2 was obtained. Additionally, a palladium-catalyzed Mizoroki-Heck reaction strategy yielded 2-aryl-2,3-dihydrobenzofuran 13 instead of derivative 12 in good yield.


Subject(s)
Glucosides/chemical synthesis , Stilbenes/chemistry , Catalysis , Glucosides/chemistry , Palladium/chemistry , Stilbenes/chemical synthesis
14.
Planta Med ; 80(2-3): 193-200, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24431013

ABSTRACT

Human pancreatic cancer cell lines have remarkable tolerance to nutrition starvation, which enables them to survive under a tumor microenvironment. The search for agents that preferentially inhibit the survival of cancer cells under low nutrient conditions is a novel antiausterity strategy in anticancer drug discovery. In this study, the methanolic extract of the leaves of Artocarpus altilis showed 100 % preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrient-deprived conditions at a concentration of 50 µg/mL. Further investigation of this extract led to the isolation of eight new geranylated dihydrochalcones named sakenins A-H (1-8) together with four known compounds (9-12). Among them, sakenins F (6) and H (8) were identified as potent preferentially cytotoxic candidates with PC50 values of 8.0 µM and 11.1 µM, respectively.


Subject(s)
Artocarpus/chemistry , Chalcones/pharmacology , Cytotoxins/pharmacology , Plant Extracts/pharmacology , Cell Line, Tumor , Cytotoxins/chemistry , Cytotoxins/isolation & purification , Humans , Nuclear Magnetic Resonance, Biomolecular , Pancreatic Neoplasms/pathology , Phytotherapy , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Tumor Microenvironment
15.
Drug Des Devel Ther ; 8: 39-47, 2014.
Article in English | MEDLINE | ID: mdl-24379655

ABSTRACT

Human pancreatic tumors are known to be highly resistant to nutrient starvation, and this prolongs their survival in the hypovascular (austere) tumor microenvironment. Agents that retard this tolerance to nutrient starvation represent a novel antiausterity strategy in anticancer drug discovery. (+)-Grandifloracin (GF), isolated from Uvaria dac, has shown preferential toxicity to PANC-1 human pancreatic cancer cells under nutrient starvation, with a PC50 value of 14.5 µM. However, the underlying mechanism is not clear. In this study, GF was found to preferentially induce PANC-1 cell death in a nutrient-deprived medium via hyperactivation of autophagy, as evidenced by a dramatic upregulation of microtubule-associated protein 1 light chain 3. No change was observed in expression of the caspase-3 and Bcl-2 apoptosis marker proteins. GF was also found to strongly inhibit the activation of Akt, a key regulator of cancer cell survival and proliferation. Because pancreatic tumors are highly resistant to current therapies that induce apoptosis, the alternative cell death mechanism exhibited by GF provides a novel therapeutic insight into antiausterity drug candidates.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Bridged-Ring Compounds/therapeutic use , Pancreatic Neoplasms/drug therapy , Bridged-Ring Compounds/pharmacology , Cell Line, Tumor , Dose-Response Relationship, Drug , Humans , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , TOR Serine-Threonine Kinases/antagonists & inhibitors
16.
Bioorg Med Chem Lett ; 24(2): 458-61, 2014 Jan 15.
Article in English | MEDLINE | ID: mdl-24380769

ABSTRACT

Series of 2-pyridineformamide thiosemicarbazones were synthesized. Their preferential cytotoxicity in nutrient deprived medium (NDM) was evaluated using PANC-1 human pancreatic cancer cells by employing an antiausterity strategy. 2-Pyridineformamide thiosemicarbazones induced apoptosis and exhibited preferential cytotoxic activity toward PANC-1 cells in NDM, with potencies in the submicromolar range. These compounds are potential candidates for the development of therapeutics against pancreatic cancer.


Subject(s)
Antineoplastic Agents/chemistry , Formamides/chemistry , Pancreatic Neoplasms/drug therapy , Pyridines/chemistry , Thiosemicarbazones/chemistry , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor/methods , Formamides/therapeutic use , Humans , Pancreatic Neoplasms/pathology , Pyridines/therapeutic use , Thiosemicarbazones/therapeutic use
17.
Fitoterapia ; 91: 148-153, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24001712

ABSTRACT

Three new cleistanthane diterpenes named tomocinon (1), tomocinol A (2), and tomocinol B (3), were isolated from the EtOAc extract of the seed of Caesalpinia sappan. Their structures were determined by extensive NMR spectroscopic analysis. The absolute stereochemistry of tomocinon (1) has been established by CD spectroscopic analysis. Cleistanthane diterpenes (1-3) represents the novel class of antiausterity agents having preferential cytotoxicity against PANC-1 human pancreatic cancer cell line under nutrient deprived condition with PC50 value of 34.7 µM, 42.4 µM and 39.4 µM, respectively.


Subject(s)
Caesalpinia/chemistry , Diterpenes/therapeutic use , Pancreatic Neoplasms/drug therapy , Phytotherapy , Plant Extracts/therapeutic use , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Cell Line, Tumor , Diterpenes/chemistry , Diterpenes/isolation & purification , Diterpenes/pharmacology , Humans , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/pharmacology , Seeds/chemistry
18.
J Nat Prod ; 75(11): 1999-2002, 2012 Nov 26.
Article in English | MEDLINE | ID: mdl-23092429

ABSTRACT

Chemical investigation of the stems of Uvaria dac yielded four new highly oxygenated cyclohexene derivatives named uvaridacols E-H (1-4). Their structures were established through NMR and circular dichroism spectroscopic analysis. Uvaridacols E (1), F (2), and H (4) displayed weak preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrition-deprived conditions in a concentration-dependent manner, without causing toxicity in normal nutrient-rich conditions.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Cyclohexenes/isolation & purification , Cyclohexenes/pharmacology , Uvaria/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Cyclohexenes/chemistry , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Pancreatic Neoplasms/drug therapy , Plant Stems/chemistry , Thailand
19.
J Nat Prod ; 75(6): 1177-83, 2012 Jun 22.
Article in English | MEDLINE | ID: mdl-22676269

ABSTRACT

Human pancreatic cancer cell lines are known for their inherent tolerance to nutrition starvation, which enables them to survive under a hypovascular (austerity) tumor microenvironment. The search for agents that preferentially retard the survival of cancer cells under low nutrition conditions (antiausterity agent) is a novel approach to anticancer drug discovery. In this study, it was found that a dichloromethane extract of the stem of Uvaria dac preferentially inhibited PANC-1 human pancreatic cancer cells survival under nutrition-deprived conditions at a concentration of 10 µg/mL. Workup of this bioactive extract led to the discovery of (+)-grandifloracin (8) as a potent antiausterity agent as evaluated in a panel of four human pancreatic cancer cell lines, PANC-1 (PC(50), 14.5 µM), PSN-1 (PC(50), 32.6 µM), MIA PaCa-2 (PC(50), 17.5 µM), and KLM-1 (32.7 µM). (+)-Grandifloracin (8) has been isolated from a natural source for the first time. Its absolute stereochemistry was established by single-crystal X-ray crystallography and circular dichroism spectroscopic analysis. In addition to this, seven other new highly oxygenated cyclohexene derivatives, named uvaridacanes A (1) and B (2), uvaridacols A-D (3, 4, 6, 7), and uvaridapoxide A (5), were also isolated and structurally characterized.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Bridged-Ring Compounds/isolation & purification , Bridged-Ring Compounds/pharmacology , Cyclohexenes/isolation & purification , Cyclohexenes/pharmacology , Pancreatic Neoplasms/drug therapy , Antineoplastic Agents, Phytogenic/chemistry , Bridged-Ring Compounds/chemistry , Crystallography, X-Ray , Cyclohexenes/chemistry , Drug Screening Assays, Antitumor , Humans , Nuclear Magnetic Resonance, Biomolecular , Thailand , Uvaria
20.
J Nat Prod ; 75(4): 764-7, 2012 Apr 27.
Article in English | MEDLINE | ID: mdl-22390627

ABSTRACT

Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is an enzyme that catalyzes hydrolysis of 3'-phosphotyrosyl bonds and is involved in repair of irreversible topoisomerase I (Top1)-DNA covalent complexes. Tdp1 inhibitors are regarded as potential cancer therapeutics in combination with Top1 inhibitors, which are currently used to treat human cancers. While screening for Tdp1 inhibitors, we discovered a novel compound, JBIR-21 (1), from the culture of an anamorphic fungus, RF-13305. The structure of 1 was established by extensive NMR and MS analyses. Compound 1 showed inhibitory activity against Tdp1 (IC(50) value, 18 µM) and cytotoxic activity against cancer cell lines (IC(50) values, 3.5-13 µM). Compound 1 also exhibited antitumor activity in a mouse xenograft model without adverse effects.


Subject(s)
Fungi/chemistry , Phosphoric Diester Hydrolases/drug effects , Sesquiterpenes/isolation & purification , Sesquiterpenes/pharmacology , Animals , Drug Screening Assays, Antitumor , Humans , Mice , Molecular Structure , Sesquiterpenes/chemistry
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