[Mechanism of Puerariae Lobatae Radix against lung cancer by inhibiting histone demethylase LSD1].

Histone lysine-specific demethylase 1(LSD1) has become a promising molecular target for lung cancer therapy. Upon the screening platform for LSD1 activity, some Chinese herbal extracts were screened for LSD1 activity inhibition, and the underlying mechanism was preliminarily investigated at both molecular and cellular levels. The results of LSD1 inhibition showed that Puerariae Lobatae Radix extract can effectively reduce LSD1 expression to elevate the expression of H3 K4 me2 and H3 K9 me2 substrates in H1975 and H1299 cells. Furthermore, Puerariae Lobatae Radix was evaluated for its anti-lung cancer activity. It had a potent inhibitory ability against the proliferation and colony formation of both H1975 and H1299 cells. Flow cytometry and DAPI staining assays indicated that Puerariae Lobatae Radix can induce the apoptosis of lung cancer cells. In addition, it can significantly suppress the migration and reverse the epithelial-mesenchymal transition(EMT) process of lung cancer cells by activating E-cadherin and suppressing the expression of N-cadherin, slug and vimentin. To sum up, Puerariae Lobatae Radix displayed a robust inhibitory activity against lung cancer, and the mechanism may be related to the down-regulation of LSD1 expression to induce the cell apoptosis and suppress the cell migration and EMT process. These findings will provide new insights into the action of Puerariae Lobatae Radix as an anti-lung cancer agent and offer new ideas for the study on the anti-cancer action of Chinese medicine based on the epigenetic modification.

[Mechanism of Atractylodes macrocephala against Alzheimer's disease via regulating lysophagy based on LKB1-AMPK-TFEB pathway].

Myloid beta(Aß) is produced by cleavage of amyloid precursor protein(APP), which is a main reason for Alzheimer's disease(AD) occurrence and development. This study preliminarily investigated the mechanism of Atractylodes macrocephala(AM) against AD based on LKB1-AMPK-TFEB pathway. The effect of AM on memory ability of AD transgenic Caenorhabditis elegans CL2241 was detected, and then the APP plasmid was transiently transferred to mouse neuroblastoma(N2 a) cells in vitro. The mice were divided into the blank control group, APP group(model group), positive control group(100 µmol·L~(-1) rapamycin), and AM low-, medium-and high-dose groups(100, 200 and 300 µg·mL~(-1)). The content of Aß_(1-42) in cell medium, the protein level of APP, the fluorescence intensity of APP, the transcriptional activity of transcription factor EB(TFEB), the activity of lysosomes in autophagy, and autophagy flux were determined by enzyme-linked immunosorbent assay(ELISA), Western blot, fluorescence microscope, luciferase reporter gene assay, RLuc-LC3 wt/RLuc-LC3 G120 A, and mRFP-GFP-LC3, respectively. The protein expression of TFEB, LC3Ⅱ, LC3Ⅰ, LAMP2, Beclin1, LKB1, p-AMPK and p-ACC was detected by Western blot. Immunofluorescence and reverse transcription-polymerase chain reaction(RT-PCR) were used to detect the fluorescence intensity of TFEB and the mRNA expression of TFEB and downstream target genes, respectively. The results showed that AM reduced the chemotactic index of transgenic C. elegans CL2241, and decreased the content of Aß in the supernatant of cell culture medium at different concentrations. In addition, AM lowered the protein level of APP and the fluorescence intensity of APP in a dose-dependent manner. Transcriptional activity of TFEB and fluorescence intensity of mRFP-GFP-LC3 plasmid were enhanced after AM treatment, and the value of RLuc-LC3 wt/RLuc-LC3 G120 A was reduced. AM promoted the protein levels of TFEB, LAMP2 and Beclin1 at different concentrations, and increased the protein expression ratio of LC3Ⅱ/LC3Ⅰ in a dose-dependent manner. Immunofluorescence results revealed that AM improved the fluorescence intensity and nuclear expression of TFEB, and RT-PCR results indicated that AM of various concentrations elevated the mRNA expression of TFEB in APP transfected N2 a cells and promoted the transcription level of LAMP2 in a dose-dependent manner, and high-concentration AM also increased the mRNA levels of LC3 and P62. The protein levels of LKB1, p-AMPK and p-ACC were elevated by AM of different concentrations. In summary, AM regulating lysophagy and degrading APP are related to the activation of LKB1-AMPK-TFEB pathway.

Sanguinarine, identified as a natural alkaloid LSD1 inhibitor, suppresses lung cancer cell growth and migration.

Objectives: Lysine-specific demethylase1 (LSD1), an important class of histone demethylases, plays a crucial role in regulation of mammalian biology. The up-regulated LSD1 expression was frequently associated with progress and oncogenesis of multiple human cancers, including non-small cell lung cancer (NSCLC). Therefore, inhibition of LSD1 may provide an attractive strategy for cancer treatment. We investigated the effect of sanguinarine against lung cancer cells as a natural alkaloid LSD1 inhibitor. Materials and Methods: The inhibition properties of sanguinarine to the recombinant LSD1 were evaluated by a fluorescence-based method. Subsequently, assays such as viability, apoptosis, clonogenicity, wound healing, and transwell were performed on H1299 and H1975 cells after treatment with sanguinarine. Results: Upon screening our in-house natural chemical library toward LSD1, we found that sanguinarine possessed a potent inhibitory effect against LSD1 with the IC50 value of 0.4 µM in a reversible manner. Molecular docking simulation suggested that sanguinarine may inactivate LSD1 by inserting into the binding pocket of LSD1 to compete with the FAD site. In H1299 and H1975 cells, sanguinarine inhibited the demethylation of LSD1, validating its cellular activity against the enzyme. Further studies showed that sanguinarine exhibited a strong capacity to suppress colony formation, inhibit migration and invasion, as well as induce apoptosis of H1299 and H1975 cells. Conclusion: Our findings present a new chemical scaffold for LSD1 inhibitors, and also provide new insight into the anti-NSCLC action of sanguinarine.

Sesquiterpene Lactams and Lactones With Antioxidant Potentials From Atractylodes macrocephala Discovered by Molecular Networking Strategy.

Atractylodes macrocephala rhizome (called Bái-zhú in China) has a long history as a functional food and herbal medicine in East Asia, especially China. Sesquiterpenoids are one of the main active compounds of Atractylodes macrocephala rhizome. This study aimed to explore the unknown sesquiterpenoids of A. macrocephala rhizome using a molecular networking strategy. Two new nitrogen-containing sesquiterpenoids, atractylenolactam A (1) and atractylenolactam B (2), and 2 new sesquiterpene lactones, 8-methoxy-atractylenolide V (6) and 15-acetoxyl atractylenolide III (7), along with 12 known analogs (3-5 and 8-16) were discovered and isolated. All the structures were assigned based on detailed spectroscopic analyses. The absolute configurations of 1, 2, 6, and 7 were established by time-dependent density functional theory ECD (TDDFT-ECD) calculations. All these compounds had different degrees of concentration-dependent activating effects on nuclear-factor-E2-related factor-2 (Nrf2).

Stellate Ganglion Blockade repairs Intestinal Mucosal Barrier through suppression of Endoplasmic Reticulum Stress following Hemorrhagic Shock.

Background: Hemorrhagic shock-induced ischemia and hypoxia elicit endoplasmic reticulum stress (ERS) that leads to cell apoptosis, tissue structural damage and organ dysfunction and failure. Stellate ganglion blockade (SGB) has been demonstrated to improve intestinal barrier dysfunction induced by hemorrhagic shock. The present study sought to investigate whether the beneficial effect of SGB on the intestinal mucosal barrier function is via suppression of ERS. Materials and methods: A conscious rat model of hemorrhagic shock (40 ±2 mmHg for 1 hour, followed by resuscitation) was established. The parameters reflecting intestinal morphology and intestinal mucosal barrier function including wet-dry ratio (W/D), intestinal permeability, D-lactic acid (D-LA) and intestinal fatty acid binding protein (I-FABP) in plasma, and expressions of ATF6α, PERK, and IRE1α in intestinal tissues were then observed. Furthermore, the effects of either SGB or ERS inhibitor, 4-phenylbutyric acid (4-PBA), on these parameters in rats with hemorrhagic shock were assessed. The effect of ERS agonist tunicamycin (TM) on the rats subjected with both SGB and hemorrhagic shock was also determined. Results: Either SGB or administration of ERS inhibitor, 4-PBA, alleviated hemorrhagic shock-induced adverse effects such as intestinal mucosal barrier dysfunction and excessive autophagy, which were characterized by damaged intestinal tissue, enhanced intestinal permeability and D-LA and I-FABP levels in plasma, and increased expressions of ATF6α, PERK, IRE1α in intestinal tissue. In contrast, administration of ERS agonist, TM, suppressed the beneficial effects of SGB on intestinal tissue and function during hemorrhagic shock. Conclusion: The SGB repairs intestinal mucosal barrier through suppression of ERS following hemorrhagic shock.

[1,2,3]Triazolo[4,5-d]pyrimidine derivatives incorporating (thio)urea moiety as a novel scaffold for LSD1 inhibitors.

Lysine specific demethylase 1 (LSD1) plays an essential role in maintaining a balanced methylation status at histone tails. Overexpression of LSD1 has been involved in the development of a variety of human diseases, including cancers. Herein, on the basis of our previously developed LSD1 inhibitors, two series of new [1,2,3]triazolo[4,5-d]pyrimidine derivatives incorporating (thio)urea moiety were designed and evaluated for their LSD1 inhibitory abilities, leading to a novel chemical class of LSD1 inhibitors. Among them, compound 31 was found to moderately inhibit LSD1 activity, as well as increase the expression of H3K4me2 at the cellular level. This compound also showed good selectivity against MAO-A/-B, and a panel of kinases such as CDK and BTK. Besides, the MTT assay suggested that the selected compounds could inhibit the proliferation of LSD1-overexpressed cancer cells. Although this class of compounds only showed moderate anti-LSD1 activity in the micromolar range, this work presents a novel chemotype of LSD1 inhibitors with good enzyme selectivity as well as cellular LSD1 inhibitory activity, and could provide a useful template for the development of more potent LSD1 inhibitors for cancer treatment.

Integrative mRNA-miRNA interaction analysis associated with the immune response of Epinephelus coioddes to Vibrio alginolyticus infection.

MicroRNAs (miRNAs) are a kind of small non-coding RNAs that have been reported to play a vital role in mediating host-pathogen interactions. High-throughput sequencing technology was applied to identify and illuminate mRNAs and miRNAs from grouper infected with Vibrio alginolyticus. The KEGG pathway enrichment analysis showed that the most significate DEGs are associated with Toll-like receptor signaling pathway and NOD-like receptor signaling pathway. We obtained 374 known miRNAs and 116 novel miRNAs. During them, there are 31 up-regulated miRNAs and 93 down-regulated miRNAs. miRNA-mRNA GO and KEGG analysis show that there are 90 miRNAs associated with the immune system. The target genes of immune-related miRNAs (miR-142, miR-146, miR-150, miR-155, miR-203, miR-205, miR-24, miR-31) and genes (CD80, IL-2, AMPK, PI3K) in Epinephelus coioddes were predicted and validated. This study provides an opportunity to further understanding the molecular mechanisms especially the immune system of miRNA regulation in Epinephelus coioddes host-pathogen interactions.

Novel 3-(2,6,9-trisubstituted-9H-purine)-8-chalcone derivatives as potent anti-gastric cancer agents: Design, synthesis and structural optimization.

To explore anti-gastric cancer agents with high efficacy and selectivity, we report the design, synthesis and optimization of a novel series of 3-(2,6,9-trisubstituted-9H-purine)-8-chalcone derivatives starting from the compound PCA-15 reported by us previously. Most of the target compounds demonstrated significant antiproliferative effects on MGC803 cancer cell line, and more potent than the positive control (PCA-15 and 5-Fu). Among them, compound 6o was identified to be the most active compound against MGC803 cell line with an IC50 value of 0.84 µM. Additionally, high selectivity was also observed between cancer and normal cells (23.35 µM against GES-1). Further mechanism studies confirmed that compound 6o could inhibit colony formation and migration, induce the apoptosis of MGC803 cells through both the mitochondrial-mediated intrinsic pathway and death receptor-mediated extrinsic pathway, which were evidenced by the up-regulation of Bax, cleaved-caspase 9/3/8, cleaved PARP and down-regulation of Bcl-2. Our systematic studies implied a new scaffold targeting gastric cancer cells for further development of small-molecule compounds with improved potency and selectivity.

Discovery of 5-Cyano-6-phenylpyrimidin Derivatives Containing an Acylurea Moiety as Orally Bioavailable Reversal Agents against P-Glycoprotein-Mediated Mutidrug Resistance.

P-glycoprotein (ABCB1)-mediated multidrug resistance (MDR) has become a major obstacle in successful cancer chemotherapy, which attracted much effort to develop clinically useful compounds to reverse MDR. Here, we designed and synthesized a novel series of derivatives with a 5-cyano-6-phenylpyrimidine scaffold and evaluated their potential reversal activities against MDR. Among these compounds, 55, containing an acylurea appendage, showed the most potent activity in reversing paclitaxel resistance in SW620/AD300 cells. Further studies demonstrated 55 could increase accumulation of PTX, interrupt ABCB1-mediated Rh123 accumulation and efflux, stimulate ABCB1 ATPase activity, and especially have no effect on CYP3A4 activity, which avoid drug interaction caused toxicity. More importantly, 55 significantly enhanced the efficacy of PTX against the SW620/AD300 cell xenograft without obvious side effects for orally intake. Given all that, the pyrimidine-acylurea based ABCB1 inhibitor may be a promising lead in developing new efficacious ABCB1-dependent MDR modulator.

A novel three-dimensional-printed paranasal sinus-skull base anatomical model.

PURPOSE: A novel precision three-dimensional (3D)-printed paranasal sinus-skull base anatomical model was generated with a commercial grade desktop 3D printer. A specific page-turning pattern was employed in this model, to display the internal spatial structure of the paranasal sinus. METHODS: The CT image data of paranasal sinus were imported into the Mimics software to construct a 3D digital paranasal sinus-skull base model. Then, the model was sliced in the coronal position and loaded into the 3D printer to print each slice of the paranasal sinus-skull base model at a ratio of 1:1 in size. Based on CT image data, nine senior doctors assessed the simulation and accuracy of the anatomical structure features of the paranasal sinus-skull base, and the advantages and educational value of the 3D printing model using a seven-point Likert scale. RESULTS: A life-like 3D paranasal sinus-skull base structural model was successfully printed, with its internal spatial details clearly displayed. Nine senior doctors all thought that the profile of the printed anatomical structure was similar to that displayed by CT scan; however, the model provided more 3D spatial visual information. In addition, the model was considered to be of great value in the anatomy teaching and complicated surgery of the paranasal sinus-skull base, which had a material cost of only 3 dollars. CONCLUSIONS: The 3D printed paranasal sinus-skull base model has 3D visual functions, which provides a novel tool for anatomical studies on paranasal sinus, resident training, pre-surgical education and surgical planning.

Discovery of 6-chloro-2-(propylthio)-8,9-dihydro-7H-purines containing a carboxamide moiety as potential selective anti-lung cancer agents.

A new series of 6-chloro-2-(propylthio)-8,9-dihydro-7H-purine-8-caboxamide derivatives were designed, synthesized, and further evaluated for their antiproliferative activities on four human cancer cell lines (A549, MGC803, PC-3 and TE-1). The structure-activity relationships (SARs) studies were conducted through the variation in the two regions, which including position 8 and 9, of purine core. One of the compounds, 8, containing a terminal piperazine appendage with a carboxamide moiety at position 8 and phenyl group at position 9 of 6-chloro-8,9-dihydro-7H-purine core, showed the most potent antiproliferative activity and good selectivity between cancer and normal cells (IC50 values of 2.80 µM against A549 and 303.03 µM against GES-1, respectively). In addition, compound 8 could inhibit the colony formation and migration of A549 cells in a concentration-dependent manner, as well as induce the apoptosis possibly through the intrinsic pathway.

Design, synthesis and in vitro biological evaluation of novel [1,2,3]triazolo[4,5-d]pyrimidine derivatives containing a thiosemicarbazide moiety.

A series of hybrid molecules containing [1,2,3]triazolo[4,5-d]pyrimidine and thiosemicarbazide moieties were designed, synthesized and evaluated for their antiproliferative activities against MGC-803, NCI-H1650 and PC-3 human cancer cells. Some of the synthesized compounds showed moderate to good activity against three selected cancer cell lines. Among these compounds, compound 29 displayed the most potent antiproliferative activity as well as good selectivity between cancer cells and normal cells. Further mechanism studies revealed that compound 29 could obviously inhibit the colony formation and migration of MGC-803 as well as induced apoptosis.

Design, synthesis and preliminary biological evaluation of 5,8-dihydropteridine-6,7-diones that induce apoptosis and suppress cell migration.

Pteridines are an important class of fused heterocycles found in natural products and drug molecules, and have shown diverse biological activities. A focused library of 5,8-dihydropteridine-6,7-dione derivatives were designed and evaluated for their antiproliferative activity against MGC-803, SGC-7901, A549 and PC-3 cancer cell lines. The SARs studies highlighted the importance of the piperazine substituted 5,8-dihydropteridine-6,7-dione frameworks for the activity and revealed essential structural elements. Among these compounds, compound 5n displayed the most potent and broad-spectrum antiproliferative inhibition against the tested cell lines and was sensitive to MGC-803 cell line, slightly more potent than 5-FU. Preliminary mechanistic studies showed that compound 5n could inhibit the colony formation and migration of MGC-803 cells. Besides, flow cytometry analysis showed that compound 5n concentration-dependently induced apoptosis of MGC-803 cells. Our studies suggest that the piperazine substituted 5,8-dihydropteridine-6,7-dione frameworks may be regarded as new chemotypes for designing effective antitumor agents targeting gastric cancer cells.

Synthesis and preliminary antiproliferative activity of new pteridin-7(8H)-one derivatives.

Pteridines are an important class of heterocyclic compounds with diverse biological activities. Here, we report a series of pteridin-7(8H)-one derivatives and their antiproliferative activities toward MKN-45, MGC-803, EC-109, and H1650. Structure-activity relationship studies showed that compound 12 exerted the most potent antiproliferative activity against MKN-45 and MGC-803 with the IC50 values of 4.32 and 7.01 µM, respectively. Besides, compound 12 induced morphological changes and apoptosis of MKN-45 cells, increased expression of Bax, down-regulated expression of Bcl-2 and caused cleavage of caspase-3/9. Additionally, we first reported the construction of the novel bicyclic 8,9-dihydro-7H-purine-8-carboxylate scaffold through the competitive 5-endo cyclization reaction with two C-N bonds and a chiral carbon center established.

Design, synthesis and preliminary biological evaluation of new [1,2,3]triazolo[4,5-d]pyrimidine/thiourea hybrids as antiproliferative agents.

A series of new [1,2,3]triazolo[4,5-d]pyrimidine/thiourea hybrids were designed and synthesized through the scaffold replacement/ring cleavage strategy. SARs studies revealed that the N-heteroarene moiety attached to the thiourea is preferred over the phenyl ring for the R2 substituents, while the hydrophobic aromatic group is beneficial for improving the activity. Among these compounds, compound 5r significantly inhibited cell growth of lung cancer cell lines H1650 and A549 (IC50 = 1.91, 3.28 µM, respectively), but was less toxic against the normal cell line GES-1 (IC50 = 27.43 µM). Mechanistic studies showed that compound 5r could remarkably inhibit the colony formation of H1650 cells, induced apoptosis possibly through the intrinsic apoptotic pathways, and arrested the cell cycle at G2/M phase. Our studies suggest that the [1,2,3]triazolo[4,5-d]pyrimidine/thiourea hybrids are a new class of chemotypes possessing interesting antiproliferative activity against lung cancer cells and could be potentially utilized for designing new antitumor agents.

Discovery of 5,6-diaryl-1,2,4-triazines hybrids as potential apoptosis inducers.

A series of 5,6-diaryl-1,2,4-triazines hybrids bearing a 1,2,3-triazole linker were synthesized by molecular hybridization strategy and evaluated for antiproliferative activity against three selected cancer cell lines (MGC-803, EC-109 and PC-3). The first structure-activity relationship (SAR) for these 5,6-diaryl-1,2,4-triazines is explored in this report with evaluation of 15 variants of the structural class. Among these chemical derivatives, 3-(((1-(4-fluorobenzyl)-1H-1,2,3-triazol-4-yl)methyl)thio)-5,6-diphenyl-1,2,4-triazine (11E) showed the more potent inhibitory effect against three cell lines than 5-Fu. Cellular mechanism studies in MGC-803 cells elucidated 11E inhibited colony formation and arrested cell cycle at G2/M phase. Furthermore, compound 11E caused morphological changes, decreased mitochondrial membrane potential, and induced apoptosis through the apoptosis-related proteins in MGC-803 cells. It was the first time, to our knowledge, that 5,6-diaryl-1,2,4-triazines bearing a 1,2,3-triazole linker were used as potential apoptosis inducers.

Design, synthesis and antiproliferative activity of thiazolo[5,4-d]pyrimidine derivatives through the atom replacement strategy.

A series of thiazolo[5,4-d]pyrimidine derivatives were designed through the atom replacement strategy based on biologically validated scaffolds and then evaluated for their antiproliferative activities on cancer cell lines. The structure-activity relationship studies were conducted, leading to the identification of compound 22, which exhibited good antiproliferative activity against HGC-27 with an IC50 value of 1.22 µM and low toxicity against GES-1 cells. Mechanistic studies showed that compound 22 inhibited the colony formation and migration of HGC-27 as well as induced apoptosis. The western blot experiments proved that compound 22 up-regulated expression of Bax, down-regulated expression levels of Bcl-2 and cleaved caspased-3/9. These findings indicate that compound 22 may serve as a template for designing new agents for the treatment of human gastric cancers. The atom replacement strategy could be viable strategy for designing new anticancer drugs and may find its applications in drug design.

Design, synthesis and preliminary antiproliferative activity studies of new diheteroaryl thioether derivatives.

A series of structurally new diheteroaryl thioether analogs was designed, prepared and screened toward MGC-803, MKN-45, EC-109 and H1650. Most of the target compounds displayed moderate to potent antiproliferative activities. Among them, compound 5 showed the best antiproliferative activity against the tested cell lines with the half maximal inhibitory concentration (IC50) values below 10µM. In addition, flow cytometry analysis showed that compound 5 increased Bax expression, down-regulated expression of Bcl-2, cleaved caspases-3/9, finally inducing apoptosis of MKN-45 cells as well asarrested the cell cycle at G2/M phase. This study suggests that the diheteroaryl thioethers are a class of emerging chemotypes for developing antitumor agents or biological probes, and compound 5 could serve as a good starting point to design new apoptosis inducers.

LPE-1, an orally active pyrimidine derivative, inhibits growth and mobility of human esophageal cancers by targeting LSD1.

Histone lysine specific demethylase 1 (LSD1) plays an important role in epigenetic modifications, and aberrant expression of LSD1 predicts tumor progression and poor prognosis in human esophageal cancers. In this study, a series of LSD1 inhibitors were synthesized and proved to be highly potent against human esophageal squamous cell carcinoma (ESCC). Our data showed that these LSD1 inhibitors selectively suppressed the viability of esophageal cancer cell line (EC-109) bearing overexpressed LSD1. Among these, compound LPE-1 (LSD1 IC50=0.336±0.003µM) significantly suppressed proliferation, induced apoptosis, arrested cell cycle of EC109 cells at G2/M phase, and caused changes of the associated protein markers correspondingly. We also found that compound LPE-1 potently inhibited the migration and invasion of EC-109 cells. Docking studies showed that the cyano group formed hydrogen bonds with Val811 and Thr810. Additionally, the thiophene moiety formed arene-H interaction with Trp761 residue. In vivo studies showed that compound LPE-1 inhibited tumor growth of xenograft models bearing EC-109 without obvious toxicity. Collectively, our findings indicate that LSD1 may be a potential therapeutic target in ESCC, and compound LPE-1 could serve as a lead compound for further development for anti-ESCC drug discovery.