Simultaneous quantification of fourteen characteristic active compounds in Eucommia ulmoides Oliver and its tea product by ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-QqQ-MS/MS).

Various kinds of bioactive compounds contribute to versatile health-promoting properties of Eucommia ulmoides Oliver (E. ulmoides). In present study, we developed a UPLC-QqQ-MS/MS method for simultaneous quantification of fourteen characteristic active compounds, including 3 lignans, 4 iridoids, 3 flavonoids and 4 phenolics in E. ulmoides and its tea product for the first time. The running time of the method is 6.5 min. It has good linearity, sensitivity, precision, accuracy, and stability. Using this high-throughput method, the distributions of fourteen characteristic active compounds in E. ulmoides and its tea product were clarified. Also, it was found that E. ulmoides tea exhibited superiority in contents of chlorogenic acid as compared with natural resources. Overall, the study provided a rapid, reliable, and efficient analysis method, which could be applied for the quality evaluation of E. ulmoides natural resources and their relative products in the field of food and medicine.

Fusarium solani G6, a novel vitexin-producing endophytic fungus: characterization, yield improvement and osteoblastic proliferation activity.

The study aimed to characterize a novel vitexin-producing endophytic fungus Fusarium solani G6 from Cajanus cajan, improve its capability for producing vitexin and evaluate its osteoblastic proliferation activity. A total of 153 endophytic fungi, classified into 6 genera, were isolated from C. cajan. Among them, only one strain, endophyte G6 identified as Fusarium solani, was found to produce vitexin. After the optimization of fermentation conditions, the highest vitexin yield (18.72 mg/L) for the strain was observed in PDB liquid medium containing 20.54 g/L of glucose and 8.90 g/L of ammonium sulfate, at an initial medium pH of 5.1 and at 28 °C for 6 days of cultivation. Moreover, the fungal vitexin exhibited notable osteoblastic proliferation stimulating activity. A novel vitexin-producing endophytic fungus F. solani G6 was characterized from C. cajan for the first time. The findings highlighted its potential use for large-scale production of vitexin and might have a promising use as therapeutic agent for osteoporosis.

FDA-approved pyrimidine-fused bicyclic heterocycles for cancer therapy: Synthesis and clinical application.

Considerable progress has been made in the development of anticancer agents over the past few decades, and a lot of new anticancer agents from natural and synthetic sources have been produced. Among heterocyclic compounds, pyrimidine-fused bicyclic heterocycles possess a variety of biological activities such as anticancer, antiviral, etc. To date, 147 pyrimidine-fused bicyclic heterocycles have been approved for clinical assessment or are currently being used in clinic, 57 of which have been approved by FDA for clinical treatment of various diseases, and 22 of them are being used in the clinic for the treatment of different cancers. As the potentially privileged scaffolds, pyrimidine-fused bicyclic heterocycles may be used to discover new drugs with similar biological targets and improved therapeutic efficacy. This review aims to provide an overview of the anticancer applications and synthetic routes of 22 approved pyrimidine-fused bicyclic heterocyclic drugs in clinic.

Discovery of [1,2,4]triazolo[1,5-a]pyrimidines derivatives as potential anticancer agents.

In this work, we reported the discovery of compound 6i with potent antiproliferative activity against MGC-803. Among these compounds, the most potent compound 6i could effectively inhibit MGC-803 (IC50 = 0.96 µM), being around 38-fold selectivity over GES-1. Further underlying mechanism studies indicated that 6i inhibited the colony formation, migration of MGC-803, and exerted anti-proliferative effect by inducing G0/G1 phase arrest in MGC-803 cells. Cell apoptosis was induced by 6i through activating mitochondria-mediated intrinsic pathway and the death receptor-mediated extrinsic pathway. 6i induced cell apoptosis by elevating the level of ROS. Also, 6i up-regulated pro-apoptotic Bax and p53 level, while down-regulating anti-apoptotic Bcl-2 protein expression. Furthermore, acute toxicity experiment indicated 6i exhibited good safety in vivo. Therefore, 6i may be a template for future development of [1,2,4]triazolo [1,5-a]pyrimidine-based anti-cancer agents.

Structure-Based Design, Synthesis, and Biological Evaluation of New Triazolo[1,5-a]Pyrimidine Derivatives as Highly Potent and Orally Active ABCB1 Modulators.

ABCB1 is a promising therapeutic target for overcoming multidrug resistance (MDR). In this work, we reported the structure-based design of triazolo[1,5-a]pyrimidines as new ABCB1 modulators, of which WS-691 significantly increased sensitization of ABCB1-overexpressed SW620/Ad300 cells to paclitaxel (PTX) (IC50 = 22.02 nM). Mechanistic studies indicated that WS-691 significantly increased the intracellular concentration of PTX and [3H]-PTX while decreasing the efflux of [3H]-PTX in SW620/Ad300 cells by inhibiting the efflux function of ABCB1. The cellular thermal shift assay suggested that WS-691 could stabilize ABCB1 by directly binding to ABCB1. WS-691 could stimulate the activity of ABCB1 ATPase but had almost no inhibitory activity against CYP3A4. Importantly, WS-691 increased the sensitivity of SW620/Ad300 cells to PTX in vivo without observed toxicity. Collectively, WS-691 is a highly potent and orally active ABCB1 modulator capable of overcoming MDR. The triazolo[1,5-a]pyrimidine may be a promising scaffold for developing more potent ABCB1 modulators.

Discovery of new [1,2,4] Triazolo[1,5-a]Pyrimidine derivatives that Kill gastric cancer cells via the mitochondria pathway.

Mitochondria are known as "powerhouse of cells" and play the role of a bridge in redox balance, cell apoptosis, and autophagy. ROS accumulation can cause mitochondria damage, while the injured mitochondria will further enhance ROS levels reciprocally. Herein, we synthesized a novel series of [1,2,4]triazolo[1,5-a]pyrimidine-based compounds 4a-4v and tested their anti-proliferation efficacy against gastric cancer cell line MGC-803. Among them, compounds 4o and 4p inhibited gastric cancer cells at micromolar level. Compound 4o caused G2/M arrest and induced mitochondria-dependent apoptosis in MGC-803 and SGC-7901. However, inhibiting apoptosis pathway cannot prevent the inhibitory activity of compound 4o against gastric cancer cell. To our surprising, ROS level was increased by compound 4o and elevation of ROS could be rescued by NAC. In accordance with that, NAC absolutely prevented the anti-proliferation efficacy of compound 4o. We further found that autophagy inhibitor CQ rather than 3-MA partially reversed inhibitory activity of compound 4o in MGC-803 cells. Taken together, compound 4o exhibited its anti-proliferative activity via increasing ROS level and inducing autophagy, thus leading to apoptosis of gastric cancer cells. Therefore, compound 4o may support further development of lead compounds for gastric cancer therapy via mitochondria pathway.

Drug repurposing: Discovery of troxipide analogs as potent antitumor agents.

Drug repurposing plays a vital role in the discovery of undescribed bioactivities in clinical drugs. Based on drug repurposing strategy, we for the first time reported a novel series of troxipide analogs and then evaluated their antiproliferative activity against MCF-7, PC3, MGC-803, and PC9 cancer cell lines and WPMY-1, most of which showed obvious selectivity toward PC-3 over the other three cancer cell lines and WPMY-1. Compound 5q, especially, could effectively inhibit PC3 with an IC50 value of 0.91 µM, which exhibited around 53-fold selectivity toward WPMY-1. Data indicated that 5q effectively inhibited the colony formation, suppressed the cell migration, and induced G1/S phase arrest in PC3 cells. Also, compound 5q induced cell apoptosis by activating the two apoptotic signaling pathways in PC3 cells: death receptor-mediated extrinsic pathway and mitochondria-mediated intrinsic pathway. Compound 5q up-regulated the expression of both pro-apoptotic Bax and P53, while down-regulated anti-apoptotic Bcl-2 expression. Besides, compound 5q significantly increased the expression of cleaved caspase 3/9 and cleaved PARP. Therefore, the successful discovery of compound 5q may further validate the feasibility of this theory, which will encourage researchers to reveal undescribed bioactivities in traditional drugs.

Discovery of tofacitinib derivatives as orally active antitumor agents based on the scaffold hybridization strategy.

In this work, a novel series of tofacitinib analogs were designed and synthesized based on the scaffold hybridization strategy and then evaluated for their antiproliferative activity toward three gastric cancer cell lines, leading to the identification of compound C18 which exhibited potent inhibitory activity against MGC-803 cell lines with an IC50 value of 2.68 µM. Compound C18 could effectively inhibit the colony formation, suppress the cell migration and induce apoptosis of MGC-803 cells through activating the p38 and JNK signaling pathways, while C18 showed no obvious effect on the cell cycle distribution in MGC-803 cells. In addition, C18 could initiate mitochondrial dysfunction of MGC-803 cells. Besides, in vivo antitumor studies indicated that C18 could inhibit gastric cancer tumor growth in vivo without obvious global toxicity.

Experience-based discovery (EBD) of aryl hydrazines as new scaffolds for the development of LSD1/KDM1A inhibitors.

Phenelzine was first employed to design new aryl hydrazine-based LSD1 inhibitors based on the experience-based discovery (EBD) strategy. Among these compounds, D8 potently inhibited LSD1 (IC50 = 882.30 nM) in a reversible manner. Compound D8 was selective to LSD1 over MAO-A/B and showed H3K4me2 competitive binding to LSD1. The interaction between H3K4me2 and LSD1 was also confirmed by the Co-IP assay. In LSD1 overexpressed A549 cells, compound D8 dose-dependently induced accumulation of LSD1 substrates H3K4me1/2 and H3K9me1/2, showed cellular target engagement to LSD1 and significantly inhibited cell migration of A549 cells. Docking studies suggested that compound D8 occupied the peptide binding region and therefore blocked the access of the peptide substrate to the FAD, finally leading to the demethylase activity inhibition of LSD1. The findings indicate that aryl hydrazines are new scaffolds for the design of LSD1 inhibitors, the identification of D8 provides further evidence for our previously proposed general principle that fused heterocycles with an amine group are potentially active toward LSD1 by competitive binding to LSD1 with H3 peptide substrates.

Synthesis, structure-activity relationship studies and biological characterization of new [1,2,4]triazolo[1,5-a]pyrimidine-based LSD1/KDM1A inhibitors.

The histone lysine specific demethylase 1 (LSD1/KDM1A) is implicated in the development of cancers, targeting LSD1 has been recognized as a promising strategy for cancer therapy. To date, some small-molecule inhibitors are currently being investigated in clinical trials. Herein we report the design, synthesis and biochemical characterization of [1,2,4]triazolo[1,5-a]pyrimidine derivatives as new LSD1 inhibitors. Of these compounds, compound C26 inhibited LSD1 in a reversible manner (IC50 = 1.72 µM) and showed selectivity to LSD1 over MAO-A/B. Besides, compound C26 displayed FAD-competitive binding to LSD1. Interestingly, C26 did not inhibit horseradish peroxidase (HRP) and quench H2O2, thus excluding the possibility that LSD1 inhibition by C26 was due to the HRP inhibition and consumption of H2O2. In LSD1 overexpressed A549 cells, compound C26 concentration-dependently induced accumulation of H3K4me1/me2 and H3K9me2 and showed cellular target engagement to LSD1. Additionally, compound C26 significantly inhibited migration of A549 cells in a concentration-dependent manner, further western blot analysis showed that C26 increased expression levels of epithelial cell markers E-Cadherin and Claudin-1, down-regulated mesenchymal cell marker N-Cadherin and the upstream transcription factors Snail and Slug. Docking studies were also performed to rationalize the potency of C26 toward LSD1. To conclude, the [1,2,4]triazolo[1,5-a]pyrimidine could serve as a promising scaffold for the development of new LSD1 inhibitors.

Association between EGFR/KRAS mutation and expression of VEGFA, VEGFR and VEGFR2 in lung adenocarcinoma.

Epidermal growth factor receptor (EGFR) and Kirsten rat sarcoma viral oncogene homolog (KRAS) are two of the most notable driver genes in lung cancer, whilst vascular endothelial growth factor (VEGF) signaling serves a critical function in tumor angiogenesis. However, few studies have focused on the potential connection between EGFR/KRAS mutational status, and VEGFA, VEGF receptor (VEGFR)1 and VEGFR2 expression in lung adenocarcinoma. EGFR (exon 19, 20 and 21) and KRAS (exon 2) mutations were detected using an amplification refractory mutation system technique, and the expression of VEGFA, VEGFR1 and VEGFR2 was analyzed using immunohistochemistry in 204 patients with lung adenocarcinoma. Associations between EGFR/KRAS mutational status and VEGFA, VEGFR1, and VEGFR2 expression was analyzed using Pearson χ2 tests. It was revealed that EGFR 21 exon (P=0.033) and EGFR 20 exon (P=0.002) mutated tumors exhibited a significantly higher level of expression of VEGFA. EGFR 21 exon mutant tumors additionally demonstrated a significantly higher level of co-expression of VEGFA and VEGFR1 (P<0.001). EGFR 19 exon mutation was significantly associated with low levels of VEGFR1 (P=0.008). KRAS mutation was significantly associated with a high level of co-expression of VEGFA, VEGFR1 and VEGFR2 (P=0.035), but no such association with the individual expression of VEGFA, VEGFR1 or VEGFR2 was identified. However, neither KRAS or EGFR mutations exhibited an association with the expression of VEGFR2. The present study may help in the treatment of various patients with KRAS or subtype of EGFR mutation with anti-angiogenesis therapy.

[Research progress on plant resources distribution of vitexin and its pharmacological effects].

Vitexin, a naturally occurring flavone glycoside in plants, has many pharmacological effects, which is widely distributed in nature. This paper reviewed the research progress of the distribution of vitexin in the plant resources and its pharmacological effects, and summarized its application prospects, aiming to provide a useful reference for the development of vitexin-enriched plant resources.