RNAseq reveals extensive metabolic disruptions in the sensitive SF-295 cell line treated with schweinfurthins

The schweinfurthin family of natural compounds exhibit a unique and potent differential cytotoxicity against a number of cancer cell lines and may reduce tumor growth in vivo. In some cell lines, such as SF-295 glioma cells, schweinfurthins elicit cytotoxicity at nanomolar concentrations. However, other cell lines, like A549 lung cancer cells, are resistant to schweinfurthin treatment up to micromolar concentrations. At this time, the precise mechanism of action and target for these compounds is unknown. Here, we employ RNA sequencing of cells treated with 50 nM schweinfurthin analog TTI-3066 for 6 and 24 h to elucidate potential mechanisms and pathways which may contribute to schweinfurthin sensitivity and resistance. The data was analyzed via an interaction model to observe differential behaviors between sensitive SF-295 and resistant A549 cell lines. We show that metabolic and stress-response pathways were differentially regulated in the sensitive SF-295 cell line as compared with the resistant A549 cell line. In contrast, A549 cell had significant alterations in response genes involved in translation and protein metabolism. Overall, there was a significant interaction effect for translational proteins, RNA metabolism, protein metabolism, and metabolic genes. Members of the Hedgehog pathway were differentially regulated in the resistant A549 cell line at both early and late time points, suggesting a potential mechanism of resistance. Indeed, when cotreated with the Smoothened inhibitor cyclopamine, A549 cells became more sensitive to schweinfurthin treatment. This study therefore identifies a key interplay with the Hedgehog pathway that modulates sensitivity to the schweinfurthin class of compounds.

Dianthiamides A–E, Proline-Containing Orbitides from Dianthus chinensis

Orbitides are plant-derived small cyclic peptides with a wide range of biological activities. Phytochemical investigation of the whole plants of Dianthus chinensis was performed with the aim to discover new bioactive orbitides. Five undescribed proline-containing orbitides, dianthiamides A–E (1–5), were isolated from a methanolic extract of Dianthus chinensis. Their structures were elucidated by extensive analysis of 1D and 2D NMR and HRESI–TOF–MS as well as ESI–MS/MS fragmentation data. The absolute configuration of the amino acid residues of compounds 1–5 was determined by Marfey’s method. All compounds were tested for their cytotoxic activity, and dianthiamide A (1) exhibited weak activity against A549 cell line with IC50 value of 47.9 μM.

Determination of Thyroidal EDCs Activities Using Approved Human Cell-Based Transactivation Assay

Endocrine-disrupting chemicals (EDCs) interfere with physiological function by mimicking or blocking hormones; these chemicals enter the human body through various materials used in food packaging, among other routes. Thyroid hormones (THs) are very important hormones that control various basic physiological functions. In a previous study, we developed a TH agonist transactivation (TA) assay based on the A549 cell line. However, the assay using A549 showed some limitations since it required 4 days to yield results and showed low sensitivity to the natural form of human triiodothyronine (T3). Therefore, in this study, we have developed a more sensitive TH TA assay based on a HeLa cell line to screen potential TH agonists. We evaluated the TH agonist activity of 17 chemicals, 5 of which showed TH agonist activity. In conclusion, in comparison with the previously developed TA assay, the assay using HeLa cells provided greater accuracy, sensitivity, and specificity, yielding more detailed results for TH agonist chemicals in less time.

Bioactive Polyketide and Diketopiperazine Derivatives from the Mangrove-Sediment-Derived Fungus Aspergillus sp. SCSIO41407

Ten polyketide derivatives (1–10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11–15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1–15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC50 values of 23.9, 39.9, and 18.6 μM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) with IC50 values of 19.2, 20.9, and 8.7 μM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 μM. In silico molecular docking with AChE and NF-κB p65 protein were also performed to understand the inhibitory activities, and 1, 11–14 showed obvious protein/ligand-binding effects to the NF-κB p65 protein.

Synthesis and Antiproliferative Activity of Phosphorus Substituted 4-Cyanooxazolines, 2-Aminocyanooxazolines, 2-Iminocyanooxazolidines and 2-Aminocyanothiazolines by Rearrangement of Cyanoaziridines

Several phosphorus-substituted N-acylated cyanoaziridines 2 and N-carbamoylated cyanoziridines 5 were prepared in good to high yields. N-Acylated cyanoaziridines 2 were used, after ring expansion, in an efficient synthesis of oxazoline derivative 3a and in a completely regio-controlled reaction in the presence of NaI. Conversely, N-carbamoyl cyanoaziridines 5 reacted with NaI to obtain a regioisomeric mixture of 2-aminocyanooxazolines 7. Mild acidic conditions can be used for the isomerization of N-thiocarbamoyl cyanoaziridine 6a into a 2-aminocyanothiazoline derivative 8a by using BF3·OEt2 as a Lewis acid. Likewise, a one pot reaction of NH-cyanoaziridines 1 with isocyanates obtained 2-iminocyanooxazolidines 9 regioselectively. This synthetic methodology involves the addition of isocyanates to starting cyanoaziridines to obtain N-carbamoyl cyanoaziridines 5, which after the ring opening, reacts with a second equivalent of isocyanate to give the final 2-imino cyanooxazolidines 9. In addition, the cytotoxic effect on the cell lines derived from human lung adenocarcinoma (A549) was also screened. 2-Iminooxazolidines 9 exhibited moderate activity against the A549 cell line in vitro. Furthermore, a selectivity towards cancer cells (A549) over non-malignant cells (MCR-5) was detected.

Stratifin as a Novel Diagnostic Biomarker in Serum for Diffuse Alveolar Damage

Among the various histopathological patterns of drug-induced interstitial lung disease (DILD), diffuse alveolar damage (DAD) is associated with poor prognosis. However, there is no reliable biomarker for its accurate diagnosis. Here, we show stratifin/14-3-3σ (SFN) as a biomarker candidate found in a proteomic analysis. The study included two independent cohorts and controls (n = 432 samples). SFN was specifically elevated in DILD patients with DAD, and was superior to the known biomarkers, KL-6 and SP-D, in discrimination of DILD patients with DAD from patients with other DILD patterns or other lung diseases, including bacterial pneumonia. SFN was also increased in serum from patients with idiopathic DAD, and in lung tissues and bronchoalveolar lavage fluid of patients with DAD. In vitro analysis using the A549 cell line suggested that extracellular release of SFN occurred via p53 activation. We conclude that serum SFN is a promising biomarker for DAD diagnosis.

Chemotherapeutic Agents Increase PD-L1 Expression in A549 Lung Cancer Cell Line

Introduction: With the highest mortality rate, lung cancer is one of the most prevalent malignancies worldwide. Increasing PD-L1 expression is one of the mechanisms of ineffective anti-tumor response and immune evasion, which causes poor prognosis and survival rate. Chemotherapy has its own limitations such as drug resistance and the escape of cancer cells from the immune system. The current research aimed to assess the effects of common chemotherapy agents used in lung cancer on PD-L1 expression in tumor cells in order to help for selecting appropriate treatment regimens to increase patient survival. Methods First, A549 cells were cultured, and the expression of PD-L1 on this cell line was measured by qRT-PCR. Then, the viability of cancer cells was examined by MTT test. PD-L1 gene expression was measured by qRT-PCR in A549 cell line, after treatment with chemotherapy agents. Results PD-L1 gene expression was increased after 24 and 48 hours after treatment with cisplatin, docetaxel, paclitaxel and carboplatin. The IC50 of the mentioned drugs 24 hours after treatment were evaluated 27, 38.79, 18.66, and 54.17 µg/ml respectively. Conclusion The current study shows that PD-L1 expression increases in response to carboplatin, docetaxel, cisplatin, and paclitaxel in A549 cell line. This indicates that chemotherapy agents cause immune evasion by increasing PD-L1 expression on cancer cells, which makes these cells resistant to the immune system. The results also showed that carboplatin, docetaxel, cisplatin, and paclitaxel at 48 hours after treatment had a greater effect on increasing PD-L1 expression than 24 hours after treatment.

Efficient Synthesis and Biological Evaluation of 6-Trifluoroethoxy Functionalized Pteridine Derivatives as EGFR Inhibitors

Background: Pteridine-based scaffolds have been widely prevalent in pharmaceuticals, such as kinase inhibitors targeting EGFR, FLT3 and PI3K/mTOR, which are attractive targets for anticancer therapy. Objective: This work aimed to design and synthesize 6-2,2,2-trifluoroethoxy functionalized pteridine-based derivatives for investigation of their anti-cancer activities as EGFR inhibitor. Method: Pteridine-based derivatives were synthesized in 6 steps involving amination, bromination, cyclization, alkoxylation, chlorination and coupling reactions. Cellular anti-proliferative activities and inhibition activities on EGFR signaling of these pteridine derivatives in vitro were determined by the MTT assay and western blot analysis, respectively. Molecular docking simulation studies were carried out by the crystallographic structure of the erlotinib/EGFR kinase domain [Protein Data Bank (PDB) code: 1M17]. Results: The compound 7m, with IC50 values of 27.40 μM on A549 cell line, exhibited comparable anti-proliferative activity relative to the positive control. Besides western blots showed its obvious down-regulation of p-EGFR and p-ERK expression at 0.8 μM. Molecular docking model displayed a hydrogen bond between Met-769 amide nitrogen and N-1 in pteridine motif of 7m which lay at the ATP binding site of EGFR kinase domain. Conclusion: The inhibition of 7m on cellular growth was comparable to that of the positive control. The inhibitory activities of 7m on EGFR phosphorylation and ERK phosphorylation in A549 cell line were relatively superior to that of the positive control. Both results suggested that the anti-proliferative activity of 7m against A549 cell line was caused by inhibition of EGFR signaling pathway, providing a new perspective for modification on pteridine-based derivatives as EGFR inhibitor.