Human Tumor Cell Research Articles

Antiviral activity of Nigella sativa oil against two SARS-CoV-2surrogates in vitro as a dietary product

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is primarily transmitted via aerosol and droplets, but environmental surfaces or potentially contaminated foods may contribute to further viral transmission. Nigella sativa seed (black cumin seed) oil possesses various biological activities against bacteria, fungi, parasites, orviruses. Objectives: This study aimed to explore black cumin seed oil (BSO) with anti-SARS-CoV-2 activities using bovine coronavirus (BCoV) and human coronavirus (HCoV) OC43 as surrogates. Methods and Results: BSO was tested at 1-100 mL/L concentrations for cytotoxicity towards human rectal tumor (HRT-18G) cells and 0.1-10 mL/L for efficacy against BCoV and HCoV OC43 in suspension. Two coronaviruses were separately mixed with BSO suspension and incubated for various times (0, 15, 30, 45, and 60 min) at 4, 23, and 37°C. The virus titerreduction was determined by median tissue culture infectious dose (TCID50) assay with HRT-18G cells as the host. BSO concentrations of 1-20 mL/L exhibited low cytotoxicity (<10%) towards HRT-18G cells. The inactivation of coronaviruses by BSO was concentration-, temperature-, and exposure time-dependent. At 37°C, BSO reduced 2.0 logs of BCoV and3.0 logs of HCoV OC43 in 60 min, respectively. Specifically, half maximal effective concentration (EC50) of BSO at 4, 23, and 37°C after the 1-h exposure was 4.28, 3.06, and 0.87 mL/L against BCoV, respectively, and 0.61, 0.61 and 0.48 mL/L against HCoV OC43, respectively. Moreover, BSO didn’t affect the attachment of BCoV and HCoV OC43 into host cells. Conclusion: Our findings on the inhibition activity of BSO against SARS-CoV-2 surrogates suggested the potential use of this natural product in mitigating SARS-CoV-2 infection. Our results also suggest that HCoV OC43 may be a more appropriate surrogate for SARS-CoV-2 to screen antiviral dietary products. Keywords: Nigella sativa, SARS-CoV-2 surrogates, antiviral activity, quantitative suspension test, dietary supplement

Abstract C056: Characterization of chromatin accessibility patterns in the human pancreas and early pancreatic neoplastic lesions using snATAC-seq

Abstract Study of early pancreas neoplasia in humans had previously been limited by lack of available tissue. Recent work by our group on deceased donor pancreata identified pancreatic intraepithelial neoplasia (PanIN) lesions in non-diseased organs and defined a transcriptomic signature for the microenvironment of these pre-cancerous lesions. Prevalence of PanINs in healthy human tissue was higher than expected and established a novel model to expand understanding of the complex biology of these precursor lesions. Epigenetic changes in chromatin structure and the subsequent effects on gene expression are essential processes in neoplasia that have yet to be described at the single cell level in the human pancreas. We hypothesized that previously defined gene signatures could identify acinar, ductal, and PanIN cells in donor pancreata based on chromatin accessibility profiling by single nuclear transposase-accessible chromatin preparation followed by high-throughput sequencing (snATAC-seq). Comparison between the accessibility patterns, transcription factor motifs, and differences in accessibility versus expression profiles can then be used to expand prior knowledge of early pancreatic neoplasia and identify novel targets for further study and therapy selection. To test this hypothesis, single nuclei from seventeen donor pancreata (twenty total samples) were isolated for snATAC-seq using the 10x Genomics platform. Data analysis was conducted using CellRanger, Seurat, Signac, AUCell, and other programs to identify and label chromatin peaks in individual nuclei corresponding to acinar, ductal, and PanIN origin according to gene signatures identified by scRNA-seq and special transcriptomics on matched donor pancreata. Using this method, cells corresponding to these gene signatures, including PanIN- like cells, were indeed identifiable with differentially accessible regions of the genome then analyzed for transcription factor motif enrichment between these cell types. Motifs enriched in cells identified as PanINs compared to either ductal or acinar cells included several transcription factors implicated in tumorigenesis. These results are similar to previously demonstrated essential factors in pancreatic neoplasia, suggesting this strategy is a relevant method for data analysis and discovery of novel factors implicated in tumorigenesis. Ongoing studies include validation of these findings in vitro using human pancreatic normal epithelial cells, human tumor cell lines, and organoid models derived from human normal and tumor samples. Together, this study demonstrates that PanINs can be identified in human pancreas tissue by snATAC-seq and that differentially expressed motifs can be identified, providing opportunity for further integration with transcriptomic information to elucidate detailed understanding of early neoplasia in the pancreas for future drug development and targeted therapeutics studies. Citation Format: Jamie N Mills, Aaron Dendekker, Joyce K Thompson, Hannah Watkoske, Simone Benitz, Padma Kadiyala, Ahmed Elhossiny, Howard Crawford, Eileen Carpenter, Marina Pasca di Magliano, Filip Bednar. Characterization of chromatin accessibility patterns in the human pancreas and early pancreatic neoplastic lesions using snATAC-seq [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr C056.

2‐Ethenyl Imidazolium Salts: Synthesis, Characterization, and Evaluation as Potential Chemotherapeutics

AbstractAs candidates for intravesical exfoliants to treat bladder cancer, we have prepared fourteen new imidazolium compounds substituted at the 2 position. These compounds were produced by use of the Knoevenagel reaction between a series of aryl aldehydes and 2‐methyl imidazolium salts. Two azolium systems were examined (benzimidazole and 4,5‐dichloroimidazole) and each of these heterocycles are substituted off the nitrogen atom positions with naphthalen‐2‐ylmethyl groups. NMR spectroscopy confirms formation of the carbon‐carbon double bond, and X‐ray crystallography confirmed that the alkenes adopt the E conformation. These new imidazolium salts were evaluated for their chemotherapeutic activity using the NCI‐60 Human Tumor Cell Line Screen, and we observed that the benzimidazolium systems were more toxic than the dichloroimidazolium systems, and that the methyl phenol ether or dimethyl aniline modified compounds showed the highest activities.

Design and Synthesis of 3-(Phenylsulfonamido)benzamide Derivatives as Potent Carbonic Anhydrase IX Inhibitors: Biological Evaluations and Molecular Modeling Studies

Introduction: Carbonic anhydrase IX (CAIX) is known to be overexpressed in various tumors and plays a significant role in tumor development and progression. Methods: A series of 3-(benzylsulfonamido)benzamides derivatives was synthesized and tested for their CAIX inhibitory activities. The two most active compounds were subjected to cytotoxicity testing against a panel of 60 cancer cell lines. Results: Many of the synthesized compounds successfully inhibited CAIX activities, exhibiting IC50 values in the low nanomolar range. The most potent CAIX inhibitor was compound 14, with an IC50 of 140 nM. Structure-activity relationship analysis of the synthesized compounds supported with molecular docking revealed strong coordination of sulfonamide moiety with the catalytic Zn2+ metal, hydrophobic interactions of the benzylsulfonamido ring with a hydrophobic pocket, and π- stacking interactions of the aryl ring with an aromatic surface. The two most active analogues (10 and 14) were further tested for their antiproliferative activities in the NCI-60 human tumor cell lines. Notably, compound 14 demonstrated potent growth inhibitory effects against several cancer cell lines. Conclusion: The synthesized analogues represent a novel scaffold for the treatment of different types of cancer by targeting CAIX.

Eicosatrienoic acid inhibits estradiol synthesis through the CD36/FOXO1/CYP19A1 signaling pathway to improve PCOS in mice

Polycystic ovary syndrome (PCOS) is a common metabolic and endocrine disorder characterized by abnormal elevation in hormone levels, with currently lacking effective treatment options. N-3 polyunsaturated fatty acids (PUFA) have broad pharmacological activity and play a beneficial role in the development of PCOS. In this study, we observed that n-3 PUFA-eicosatrienoic acid (ETA) improves the estrous cycle and ovarian morphology in dehydroepiandrosterone (DHEA)-induced PCOS mice, particularly serum hormone levels. Additionally, it suppresses the expression of CYP19A1 and E2 synthesis in human granulosa-like tumor cell line (KGN) cells. Further investigation revealed that ETA significantly upregulates the expression of CD36, cAMP, P-PKA, and FOXO1 in KGN cells and mouse ovaries to lower E2 levels. This conclusion was supported by inhibiting CD36 and FOXO1 at both the mouse and cellular levels. Additionally, ETA treatment decreased the expression of ESR1, Kiss1, Gnrh in the hypothalamus, and GnRHR, Lhβ, Egr1, Pitx1, Sf1 in the pituitary of PCOS mice. No differences were observed after ETA treatment in the CD36 and FOXO1 inhibitor groups, indicating that ETA improves PCOS mice by regulating the hypothalamic-pituitary axis through E2 synthesis inhibition. In summary, we have elucidated for the first time the mechanism by which CD36 regulates E2 synthesis in ovarian granulosa cells and demonstrated that ETA activates the CD36 receptor to inhibit E2 synthesis through the cAMP/PKA/FOXO1/CYP19A1 signaling pathway, thereby improving hormonal imbalance and treating PCOS. This provides a new strategy for the effective prevention and treatment of PCOS.

Substituent effect on the chemical and biological properties of diisatin dihydrazone Schiff bases: DFT and docking studies

According to the considered role of lipophilicity-hydrophobicity on organic Schiff base hydrazones, different substituents of phenyl, ethyl, and methyl groups were inserted in the synthetic strategy of diisatin dihydrazones (L1–4). The biochemical enhancement was evaluated depending on their inhibitive potential of the growth power of three human tumor cells, fungi, and bacteria. The biochemical assays assigned the effected role of different substituents of phenyl, ethyl, and methyl groups on the effectiveness of their diisatin dihydrazone reagents. The interacting modes with calf thymus DNA (i.e. Ct-DNA) were studied via viscometric and spectrophotometric titration.The organo-reagent L1 with the oxalic derivative assigned a performed inhibitive action for the examined microbes and the human tumor cell lines growing up over the terephthalic (L4) > malonic (L2) > succinic (L3) ones. From Kb = binding constant, and ∆Gb≠ = Gibb’s free energy values, the binding of interaction within Ct-DNA was evaluated for all compounds (L1–4), in which L1, L3, and L4 assigned the highest reactivity referring to the covalent/non-covalent modes of interaction, as given for (L1–4), 14.32, 13.28, 10.87, and 12.41 × 107 mol−1 dm3, and −45.17, −43.24, −43.75, and −44.05 kJ mol−1, respectively. DFT and docking studies were achieved to support the current work.

Exploring the Anticancer Potential of Phenolic nor-Triterpenes from Celastraceae Species.

To explore new compounds with antitumour activity, fifteen phenolic nor-tripterpenes isolated from Celastraceae species, Maytenus jelskii, Maytenus cuzcoina, and Celastrus vulcanicola, have been studied. Their chemical structures were elucidated through spectroscopic and spectrometric techniques, resulting in the identification of three novel chemical compounds. Evaluation on human tumour cell lines (A549 and SW1573, non-small cell lung; HBL-100 and T-47D, breast; HeLa, cervix, and WiDr, colon) revealed that three compounds, named 6-oxo-pristimerol, demethyl-zeylasteral, and zeylasteral, exhibited significant activity (GI50 ranging from 0.45 to 8.6 µM) on at least five of the cell lines tested. Continuous live cell imaging identified apoptosis as the mode of action of selective cell killing in HeLa cells. Furthermore, their effect on a drug-sensitive Saccharomyces cerevisiae strain has been investigated to deepen on their mechanism of action. In dose-response growth curves, zeylasteral and 7α-hydroxy-blepharodol were markedly active. Additionally, halo assays were conducted to assess the involvement of oxidative stress and/or mitochondrial function in the anticancer profile, ruling out these modes of action for the active compounds. Finally, we also delve into the structure-activity relationship, providing insights into how the molecular structure of these compounds influences their biological activity. This comprehensive analysis enhances our understanding of the therapeutic potential of this triterpene type and underscores its relevance for further research in this field.

Evaluation of newly synthesized 2-(thiophen-2-yl)-1H-indole derivatives as anticancer agents against HCT-116 cell proliferation via cell cycle arrest and down regulation of miR-25

In the present study, we prepared new sixteen different derivatives. The first series were prepared (methylene)bis(2-(thiophen-2-yl)-1H-indole) derivatives which have (indole and thiophene rings) by excellent yield from the reaction (2 mmol) 2-(thiophen-2-yl)-1H-indole and (1 mmol) from aldehyde. The second series were synthesized (2-(thiophen-2-yl)-1H-indol-3-yl) methyl) aniline derivatives at a relatively low yield from multicomponent reaction of three components 2-(thiophen-2-yl)-1H-indole, N-methylaniline and desired aldehydes. The anticancer effect of the newly synthesized derivatives was determined against different cancers, colon, lung, breast and skin. The counter screening was done against normal Epithelial cells (RPE-1). The effect on cell cycle and mechanisms underlying of the antitumor effect were also studied. All new compounds were initially tested at a single dose of 100 μg/ml against this panel of 5 human tumor cell lines indicated that the compounds under investigation exhibit selective cytotoxicity against HCT-116 cell line and compounds (4g, 4a, 4c) showed potent anticancer activity against HCT-116 cell line with the inhibitory concentration IC50 values were, 7.1±0.07, 10.5± 0.07 and 11.9± 0.05 μΜ/ml respectively. Also, the active derivatives caused cell cycle arrest at the S and G2/M phase with significant(p < 0.0001) increase in the expression levels of tumor suppressors miR-30C, and miR-107 and a tremendous decrease in oncogenic miR-25, IL-6 and C-Myc levels. It is to conclude that the anticancer activity could be through direct interaction with tumor cell DNA like S-phase-dependent chemotherapy drugs. Which can interact with DNA or block DNA synthesis such as doxorubicin, cisplatin, or 5-fluorouracil and which were highly effective in killing the cancer cells. This data ensures the efficiency of the 3 analogues on inducing cell cycle arrest and preventing cancer cell growth. The altered expressions explained the molecular mechanisms through which the newly synthesized analogues exert their anticancer action.

Development of an Elastin-like Polypeptide-Based Nucleic Acid Delivery System Targeted to EGFR+ Bladder Cancer Cells Using a Layer-by-Layer Approach.

Nucleic acid (NA)-based therapies are revolutionizing biomedical research through their ability to control cellular functions at the genetic level. This work demonstrates a versatile elastin-like polypeptide (ELP) carrier system using a layer-by-layer (LbL) formulation approach that delivers NA cargos ranging in size from siRNA to plasmids. The components of the system can be reconfigured to modulate the biochemical and biophysical characteristics of the carrier for engaging the unique features of the biological target. We show the physical characterization and biological performance of LbL ELP nucleic acid nanoparticles (LENNs) in murine and human bladder tumor cell lines. Targeting bladder tumors is difficult owing to the constant influx of urine into the bladder, leading to low contact times (typically <2 h) for therapeutic agents delivered via intravesical instillation. LENN complexes bind to bladder tumor cells within 30 min and become rapidly internalized to release their NA cargo within 60 min. Our data show that a readily adaptable NA-delivery system has been created that is flexible in its targeting ability, cargo size, and disassembly kinetics. This approach provides an alternative path to either lipid nanoparticle formulations that suffer from inefficiency and physicochemical instability or viral vectors that are plagued by manufacturing and immune rejection challenges. This agile ELP-based nanocarrier provides an alternative route for nucleic acid delivery using a biomanufacturable, biodegradable, biocompatible, and highly tunable vehicle capable of targeting cells via engagement with overexpressed cell surface receptors.

Antiproliferative potential of Plinia edulis leaves

Plinia edulis, popularly known as ‘cambucá’, is used in Brazilian folk medicine to treat several conditions. The aim of this study was to evaluate the mutagenicity and cytotoxicity of cambucá leaf extract, as well as its antioxidant activity. The ‘Ames’ test and Orac assay were used to evaluate the mutagenicity and antioxidant activity, respectively, and the phytochemical analysis of the ethanol leaf extract (LE) was performed by chromatographic and spectrometric methods. The in vitro cytotoxicity was tested on CHO (Chinese Hamster Ovary) cells and on nine human tumor cell lines. Phytochemical analysis of LE has revealed the presence of triterpenes and flavonoids. The LE did not show mutagenicity at the concentration of 20 mg plate-1 and exhibited high antioxidant activity, with Orac value of 3948 µmol TE g-1. The LE and its fractions (ethyl acetate; methanol) showed antiproliferative activity against cancer cell lines and proliferative activity in normal cells. The ethyl acetate fraction was the most active extract, presenting antiproliferative activity against strains of breast cancer, prostate cancer, colon cancer, lung cancer, melanoma and leukemia (GI50 0.01-8.57 µg mL-1), being more effective than the reference drug (doxorubicin) against human breast adenocarcinoma MCF-7 cell line. These results suggest P. edulis as a potential adjuvant in cancer therapy and chemoprevention.

Panicum maximum Jacq. mediated green synthesis of silver nanoparticles: synthesis, characterization, and biological activities supported by molecular docking

This study uses the aerial parts of Panicum maximum total extract (PMTE) to synthesize silver nanoparticles (AgNPs) in an environmentally friendly manner. TEM, SEM, FTIR, X-ray powder diffraction (XRD), Zeta potential, UV, and FTIR were used to characterize the green silver nanoparticles (PM-AgNPs). PM-AgNPs were evaluated as anticancer agents compared to (PMTE) against breast (MCF-7), lung (A549), and ovary adenocarcinoma (SKOV3) human tumour cells. The antibacterial activity of AgNPs was assessed against Staphylococcus aureus isolates. The PM-AgNPs had an absorbance of 418 nm, particle size of 15.18 nm, and zeta potential of −22.4 mV, ensuring the nanosilver’s stability. XRD evaluated the crystallography nature of the formed PM-AgNPs. The cytotoxic properties of PM-AgNPs on MCF-7 and SKOV 3 were the strongest, with IC50s of 0.13 ± 0.015 and 3.5 ± 0.5 g/ml, respectively, as compared to A549 (13 ± 3.2 µg/mL). The increase in the apoptotic cells was 97.79 ± 1.61 and 96.6 ± 1.91% for MCF-7 and SKOV3 cell lines, respectively. PM-AgNPs were found to affect the membrane integrity and membrane permeability of 50 and 43.75% of the tested isolates, respectively. Also, PM-AgNPs have recorded a reduction in the biofilm formation of S. aurues. These results suggest using PM-AgNPs to treat breast and ovarian cancers.

Discovery of Potent Isoquinolinequinone N-Oxides to Overcome Cancer Multidrug Resistance.

Multidrug resistance (MDR) of human tumors has resulted in an immediate need to develop appropriate new drugs. This work outlines the development of 20 potent IQQ N-oxide derivatives in two isomeric families, both exhibiting nanomolar GI50 against human tumor cell lines. Preliminary NCI-60 tumor screening sees the C(6) isomers achieve a mean GI50 > 2 times lower than the corresponding C(7) isomers. MDR evaluation of nine selected compounds reveals that each presents lower GI50 concentrations in two MDR tumor cell lines. Four of the series display nanomolar GI50 values against MDR cells, having selectivity ratios up to 2.7 versus the sensitive (parental) cells. The most potent compound 25 inhibits the activity of drug efflux pumps in MDR cells, causes significant ROS accumulation, and potently inhibits cell proliferation, causing alterations in the cell cycle profile. Our findings are confirmed by 3D spheroid models, providing new candidates for studies against MDR cancers.

Cytotoxic diterpenoids from Croton kongensis inhibiting tumor proliferation and migration

Thirty-two diterpenoids including 18 ent-kauranes (1–6, and 12–23), nine 8,9-seco-ent-kauranes (7–8, and 24–30), four ent-abietanes (9–10, and 31–32), and one crotofolane (11) were isolated from the twigs and leaves of Croton kongensis. The structures of previously unreported crokokaugenoids A–H (1–8), crokoabiegenoids A–B (9–10), and crokocrotogenoid A (11) were determined by spectroscopic data analyses, TDDFT-ECD and GIAO NMR calculations, and X-ray crystallographic studies. All compounds were evaluated for their cytotoxic activity against five human tumor cell lines, and the structure–activity relationships were discussed. Biological tests exhibited that compound 1 possessed strong anti-proliferation activity, arrested cell cycle at G2/M phase, and induced cell apoptosis of MDA-MB-231. The mechanism investigation showed that compound 1 can inhibit tumor proliferation and migration by targeting mitochondria to increase intracellular reactive oxygen species (ROS) and regulating STAT3 and FAK signal pathways. Collectively, these findings supported the great potential of compound 1 as a hopeful anticancer agent.

Small Molecule Induces Time-Dependent Inhibition of Stat3 Dimerization and DNA-Binding Activity and Regresses Human Breast Tumor Xenografts.

Aberrantly-active signal transducer and activator of transcription (Stat)3 has a causal role in many human cancers and represents a validated anticancer drug target, though it has posed significant challenge to drug development. A new small molecule, JKB887, was identified through library screening and is predicted to interact with Lys591, Arg609 and Pro63 in the phospho-tyrosine (pTyr)-binding pocket of the Stat3 SH2 domain. JKB887 inhibited Stat3 DNA-binding activity in vitro in a time-dependent manner, with IC50 of 2.2-4.5 μM at 30-60-min incubation. It directly disrupted both the Stat3 binding to the cognate, high-affinity pTyr (pY) peptide, GpYLPQTV-NH2 in fluorescent polarization assay with IC50 of 3.5-5.5 μM at 60-90-min incubation, and to the IL-6 receptor/gp130 or Src in treated malignant cells. Treatment with JKB887 selectively blocked constitutive Stat3 phosphorylation, nuclear translocation and transcriptional activity, and Stat3-regulated gene expression, and decreased viable cell numbers, cell growth, colony formation, migration, and survival in human or mouse tumor cells. By contrast, JKB887 had minimal effects on Stat1, pErk1/2MAPK, pShc, pJAK2, or pSrc induction, or on cells that do not harbor aberrantly-active Stat3. Additionally, JKB887 inhibited growth of human breast cancer xenografts in mice. JKB887 is a Stat3-selective inhibitor with demonstrable antitumor effects against Stat3-dependent human cancers.

Broad-spectrum anti-cancer activity of fused human arginase variants.

The rapid increase in cancer cases worldwide necessitates the development of novel therapeutic approaches. Therapies targeting cancer's altered metabolism, especially those that deplete critical amino acids, have emerged as promising ones, some of which are already being used in clinical practice and many others are under development. This study reports the anti-cancer activity of two novel fused human arginase I (FHA) variants, FHA-3 and FHA-12, assessed using the NCI-60 human tumor cell line panel. Both variants have demonstrated a range of potencies in a single-dose assay (10µM), but FHA-3 was found to be more potent with significant growth inhibition in most tested cell lines.To calculate 50% growth inhibition (GI50), FHA-3 was further evaluated in a five-dose assay, where notable anti-cancer activity was observed across the nine cancer types of the NCI-60 panel. Our results demonstrated the broad-spectrum anti-cancer activity of novel FHA variants, with FHA-3 being the most potent. Further studies elucidating its efficacy in animal models will help explore its therapeutic potential.

Inhibition of SUMOylation Induces Adaptive Antitumor Immunity against Pancreatic Cancer through Multiple Effects on the Tumor Microenvironment.

Improvement of outcome in patients with pancreatic ductal adenocarcinoma (PDAC) requires exploration of novel therapeutic targets. Thus far, most studies of PDAC therapies, including those inhibiting small ubiquitin-like modifications (SUMOylation), have focused on PDAC epithelial cell biology, yet SUMOylation occurs in a variety of cell types. The mechanisms by which SUMOylation impacts PDAC in the context of its tumor microenvironment are poorly understood. We used clinically relevant orthotopic PDAC mouse models to investigate the effect of SUMOylation inhibition using a specific, clinical-stage compound, TAK-981. In contrast to its inhibition of PDAC cell proliferation in vitro, the survival benefit conferred by TAK-981 in vivo is dependent on the presence of T cells, suggesting that induction of adaptive antitumor immunity is an important antitumor effect of SUMOylation inhibition in vivo. To understand how this adaptive antitumor immunity is promoted, we investigated how SUMOylation inhibition in vivo alters major cell types/subtypes and their communications in the PDAC tumor microenvironment by performing transcriptomic analyses at single-cell resolution, which allowed mapping of cells in our orthotopic mouse model to cells in human PDAC tumors based on gene expression profiles. Findings are further validated by flow cytometry, immunofluorescence, IHC, western blots, and qPCR. The single-cell transcriptome dataset provided here suggests several combination strategies to augment adaptive immune responses that are necessary for durable disease control in patients with PDAC.

Silvaticusins A–D: ent-kaurane diterpenoids and a cyclobutane-containing ent-kaurane dimer from Isodon silvaticus

Three new ent-kaurane diterpenoids, silvaticusins A–C (1–3), along with a new ent-kaurane dimer silvaticusin D (4) were isolated from the aerial parts of Isodon silvaticus. The structures of these new compounds were established mainly by comprehensive analysis of their NMR and MS data. The absolute configuration of compounds 1 and 4 were determined using a single-crystal X-ray diffraction and computational methods, respectively. Compounds 2 and 3 were found to exhibit remarkable cytotoxic effects against five human tumor cell lines (HL-60, A-549, SMMC-7721, MDA-MB-231, and SW-480), with IC50 values spanning from 1.27 ± 0.08 to 7.52 ± 0.33 μM.Graphical

Rhythms in lipid droplet content driven by a metabolic oscillator are conserved throughout evolution

The biological clock in eukaryotes controls daily rhythms in physiology and behavior. It displays a complex organization that involves the molecular transcriptional clock and the redox oscillator which may coordinately work to control cellular rhythms. The redox oscillator has emerged very early in evolution in adaptation to the environmental changes in O2 levels and has been shown to regulate daily rhythms in glycerolipid (GL) metabolism in different eukaryotic cells. GLs are key components of lipid droplets (LDs), intracellular storage organelles, present in all living organisms, and essential for energy and lipid homeostasis regulation and survival; however, the cell bioenergetics status is not constant across time and depends on energy demands. Thus, the formation and degradation of LDs may reflect a time-dependent process following energy requirements. This work investigated the presence of metabolic rhythms in LD content along evolution by studying prokaryotic and eukaryotic cells and organisms. We found sustained temporal oscillations in LD content in Pseudomonas aeruginosa bacteria and Caenorhabditis elegans synchronized by temperature cycles, in serum-shock synchronized human embryonic kidney cells (HEK 293 cells) and brain tumor cells (T98G and GL26) after a dexamethasone pulse. Moreover, in synchronized T98G cells, LD oscillations were altered by glycogen synthase kinase-3 (GSK-3) inhibition that affects the cytosolic activity of the metabolic oscillator or by knocking down LIPIN-1, a key GL synthesizing enzyme. Overall, our findings reveal the existence of metabolic oscillations in terms of LD content highly conserved across evolutionary scales notwithstanding variations in complexity, regulation, and cell organization.Graphical abstract

Cordycepin suppresses steroidogenic acute regulatory protein expression by reducing SP1 in human granulosa-lutein cells.

Cordycepin (COR), a compound derived from Cordyceps, is recognized as an adenosine analog with numerous beneficial effects on human health. However, its impact on steroidogenic acute regulatory protein (STAR) expression in ovarian granulosa cells is not well understood. This study demonstrates that COR downregulates STAR expression by reducing the expression of the SP1 transcription factor. Cordycepin (COR), a pure compound of Cordyceps, is known as an adenosine analog that exerts many beneficial effects on human health. The steroidogenesis mediated by ovarian granulosa cells is pivotal in maintaining normal female reproductive function. The steroidogenic acute regulatory protein (STAR) regulates the rate-limiting step in steroidogenesis. COR has been shown to stimulate STAR expression in mouse Leydig cells, the steroidogenic cells in the testes. However, the effect of COR on STAR expression in ovarian granulosa cells remains undetermined. In the present study, we show that treatment with COR downregulates STAR expression in a steroidogenic human granulosa-like tumor cell line, KGN, and primary culture of human granulosa-lutein (hGL) cells obtained from patients undergoing in vitro fertilization. We used specific adenosine receptor (AR) antagonists, and our results reveal that the inhibitory effect of COR on STAR expression is mediated by AR-A1, AR-A2A, and AR-A3. In both KGN and primary hGL cells, COR activates ERK1/2 and AKT signaling pathways, but only activation of ERK1/2 is required for the COR-induced downregulation of STAR expression. In addition, our results demonstrate that COR downregulates STAR expression by reducing the expression of the SP1 transcription factor. These results provide a better understanding of the biological function of COR on STAR expression in the ovary, which may lead to the development of alternative therapeutic approaches for female reproductive disorders.

Brønsted Acid Catalyzed Asymmetric Synthesis of Cyclopentenones with C4-Quaternary Centers Starting from Vinyl Sulfoxides and Allenyl Ketones or Allenoates.

Starting with chiral vinyl sulfoxides and allenyl ketones or allenoates, a triflic acid-catalyzed asymmetric [3,3]-sigmatropic rearrangement of sulfoniums is reported to have a direct access to highly functionalized C4-chiral cyclopentenones (19 examples, up to 85% yield and >95% enantiomeric excesses). In addition to the use of these chiral compounds as key building blocks in organic synthesis, the antiproliferative activities of sulfoxide substrates and the corresponding cyclopentenones were evaluated, and promising cytotoxicity against the HL-60 human tumor cell line was found.