Chemical constituents of Callistemon citrinus from Egypt and their antiausterity activity against PANC-1 human pancreatic cancer cell line.

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.

Highly Potent Antiausterity Agents from Callistemon citrinus and Their Mechanism of Action against the PANC-1 Human Pancreatic Cancer Cell Line.

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.

Discovery of potential antiausterity agents from the Japanese cypress Chamaecyparis obtusa.

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.

Highly oxygenated antiausterity agents from the leaves of Uvaria dac.

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).

Evaluation of synthetic coumarins for antiausterity cytotoxicity against pancreatic cancers.

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.

Attempt to synthesize 2,3,5,4'-tetrahydroxystilbene derived from 2,3,5,4'-tetrahydroxystilbene-2-O-ß-glucoside (THSG).

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.

Discovery of 2-pyridineformamide thiosemicarbazones as potent antiausterity agents.

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.

Geranyl dihydrochalcones from Artocarpus altilis and their antiausteric activity.

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.

Analysis of the biological activity of a novel 24-membered macrolide JBIR-19 in Saccharomyces cerevisiae by the morphological imaging program CalMorph.

To investigate the biological activity of a novel 24-membered macrolide compound, JBIR-19, isolated from the culture broth of the entomopathogenic fungus Metarhizium sp. fE61, morphological changes in yeast cells were examined using the automated image-processing program CalMorph. Principal components analysis was used to elucidate dynamic changes in the phenotypes, revealing two independent effects of JBIR-19 in yeast cells: bud elongation and increased size of the actin region. Using a fitness assay, we identified the genes required for robust growth in the presence of JBIR-19. Among these were CCW12, YLR111W, and DHH1, which are also involved in abnormal bud morphology. Based on these results and others, we predict intracellular targets of JBIR-19 and its functional interactions.

Antiausterity agents from Uvaria dac and their preferential cytotoxic activity against human pancreatic cancer cell lines in a nutrient-deprived condition.

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.

Tyrosyl-DNA phosphodiesterase 1 inhibitor from an anamorphic fungus.

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.

Uvaridacols E-H, highly oxygenated antiausterity agents from Uvaria dac.

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.

A phenylacetylated peptide, JBIR-96, isolated from Streptomyces sp. RI051-SDHV6.

Searching for metabolites from Streptomyces sp. RI051-SDHV6 resulted in the discovery of a novel peptide, JBIR-96 (1). The structure of 1 was established as an N-phenylacetylated pentapeptide involving a cysteic acid and a peptide lactone structure by extensive NMR and MS analyses. In addition, the absolute configuration of 1 was established by Marfey's and modified Mosher's methods.

A Randomized Controlled Trial Evaluating the Effectiveness of a Short Video-Based Educational Program for Improving Mental Health Literacy Among Schoolteachers.

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.

Effects of varying the standard deviation of the luminance on the appearance of food, flavour expectations, and taste/flavour perception.

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.

Real-world effectiveness and safety of nivolumab in patients with non-small cell lung cancer: A multicenter retrospective observational study in Japan.

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.

New glycosylated derivatives of versipelostatin, the GRP78/Bip molecular chaperone down-regulator, from Streptomyces versipellis 4083-SVS6.

Four novel glycosylated derivatives of versipelostatin (1), versipelostatins B-E (2-5), were isolated from the culture broth of Streptomyces versipellis 4083-SVS6. The inhibitory activities of the isolated compounds against the expression of molecular chaperone GRP78 induced by 2-deoxyglucose were evaluated. Of the five versipelostatin family members, 1 and 4 were the more potent with IC(50) values of 3.5 and 4.3 microM. These results suggest that the alpha-L-oleandropyranosyl (1-->4)-beta-D-digitoxopyranosyl residue in the sugar moiety may play an important role in down-regulating GRP78 expression induced by 2-deoxyglucose.

Aminocaprophenone- and pyrrolidine-type alkaloids from the leaves of Ficus septica.

Two new aminocaprophenone alkaloids, ficuseptamines A (1) and B (2), and a new pyrrolidine alkaloid, ficuseptamine C (3), together with 12 known alkaloids and a known acetophenone derivative were isolated from a methanolic extract of the leaves of Ficus septica. The structures of 1-3 were determined on the basis of their spectroscopic data. The compounds obtained were evaluated for cytotoxicity against two cancer cell lines.

Discovery of a pimaricin analog JBIR-13, from Streptomyces bicolor NBRC 12746 as predicted by sequence analysis of type I polyketide synthase gene.

Sequence analysis of ketosynthase domain amplicons from Streptomyces bicolor NBRC 12746(T) revealed the presence of previously unreported type I polyketide synthases (PKS-I) genes. The clustering of these genes with the reference PKS-1 sequences suggested the possibility to produce a polyene compound similar to pimaricin. Thus, the cultured sample from NBRC 12746(T) was analyzed for the production of polyene compounds. The strain produced an antifungal compound which displayed the UV absorption spectrum of tetraene macrolides. The structure determination based on the spectroscopic analysis of the purified compound resulted in the identification of a novel pimaricin analog JBIR-13 (1). This study therefore strongly suggested that a careful analysis of PKS-I genes can provide valuable information in the search of novel bioactive compounds within a class predicted from phylogenetic analysis.