A fast and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of prodrug of paclitaxel (Pro-PTX) and paclitaxel (PTX) in rat plasma was developed. The plasma samples were subjected to protein precipitation with acetonitrile (0.1% formic acid), and then separated by LC with an Ultimate AQ-C18 column (50 mm × 3.0 mm, 3 μm) and acetonitrile-1 mmol·L^-1 ammonium formate (containing 0.1% formic acid) as the mobile phase. Multiple reaction monitoring (MRM) scanning mode was used to detect the ion responses m/z 983.4→415.2 (Pro-PTX), m/z 854.4→286.1 (PTX) and m/z 808.3→527.2 (Docetaxel, internal standard) by using a triple quadrupole tandem mass spectrometer with electrospray ionization source and positive ion mode. The method validation results show that the linear ranges of Pro-PTX and PTX in plasma were 2.00-500 ng·mL^-1 (r > 0.99) and 4.00-1 000 ng·mL^-1 (r > 0.99), the lower limit of quantification was 2.00 ng·mL^-1 and 4.00 ng·mL^-1, respectively; the quality control samples with low, medium and high concentrations of Pro-PTX and PTX were within the batch, the relative standard deviation (RSD) between batches were all less than 9%; the relative deviation (RE) was within the range of ± 9%; In the stability test, both Pro-PTX and PTX in plasma were stable under various storage conditions. The method was sensitive, specific, and reproducible, and was suitable for the pharmacokinetic study of Pro-PTX in rats. Animal experiments were approved by the Ethics Committee of Laboratory Animal Management and Animal Welfare, Institute of Materia Medica, Chinese Academy of Medical Sciences (No.: 00003552).

In this study, butaselen-2, 6-dimethyl-β-cyclodextrin inclusion complexes were prepared by saturated aqueous solution method to improve the solubility of butaselen, so as to obtain its injection solutions. The content of butaselen in the inclusions was determined by high performance liquid chromatography (HPLC), and then the preparation process was optimized by orthogonal design using the inclusion ratio as an indicator. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to verify the structure of the inclusions. The effects of the inclusions on the solubility and stability of butaselen were also investigated. The results showed that the optimized preparation process with a mass ratio of 1:340, an encapsulation time of 3 h and an encapsulation temperature of 70 ℃ resulted in an encapsulation ratio of (91.24 ± 0.42) %, and the results of XRD, FTIR and SEM demonstrated the formation of inclusion complexes. The developed HPLC method is rapid, simple, accurate, applicable, specific and reproducible for the determination of butaselen content in butaselen cyclodextrin inclusion complexes, which can lay the foundation for the development of new butaselen dosage forms and clinical applications and provide technical support.

This study investigated the inhibitory effect and mechanisms of cryptotanshinone (CPT) on tamoxifen resistant cell MCF7-TAMR. The inhibitory effect of CPT on the viability of MCF7-TAMR cells was evaluated using the MTT assay. We found that CPT significantly inhibited the growth of MCF7-TAMR cells in a dose- and time-dependent manner. The half inhibitory concentration (IC₅₀) is 15.14 ± 2.82 μmol·L^-1 at 24 h. CPT induced cell cycle arrest of MCF7-TAMR cells at G0/G1 phase, and promoted apoptosis of MCF7-TAMR cells by upregulating intracellular levels of reactive oxygen species (ROS). Transwell results showed that CPT significantly inhibited the migration of MCF7-TAMR cells. Furthermore, CPT decreased the CD24^-/lowCD44⁺ cell population in MCF7-TAMR cell-derived microspheres. Western blot results showed that CPT effectively inhibited the phosphorylation of estrogen receptor α (ER-α), and reduced the expression of phosphatidylinositol 3-kinase (PI3K-p85), serine-threonine protein kinase (Akt) and multidrug transporter ATP-binding cassette superfamily G member 2 (ABCG2). These results showed that CPT can induce cell apoptosis, cause cell cycle arrest, inhibit cell migration and inhibit ER-α phosphorylation, inhibit PI3K/Akt signaling pathway, reduce the number of CD24^-/lowCD44⁺ cells and the expression of ABCG2, overcome cell drug resistance.

4-(Cytidine 5′-diphospho)-2-C-methyl-D-erythritol kinase (CMK) was one of the key enzymes in the methylerythritol-4-phosphate (MEP) pathway to generate terpenoids. In this study, based on the transcriptome data of Atractylodes lancea, the sequence of the CMK gene was cloned, named AlCMK (GenBank accession number OM283293). The results showed that AlCMK contains a 1 230 bp open reading frame (ORF) encoding 409 amino acids. The deduced protein had a theoretical molecular weight of 44 752.53 and an isoelectric point of 6.67. Transmembrane structure analysis showed that there was no transmembrane structure, and the secondary structure of AlCMK was predicted to be mainly composed of random coil. Homologous alignment revealed that AlCMK shared high sequence identity with the CMK proteins of Tanacetum cinerariifolium, Osmanthus fragrans, Eucommia ulmoides, Lonicera japonica and Salvia miltiorrhiza. Phylogenetic analysis indicated that AlCMK protein had the higher homology with CMK protein of Compositae. The pET-32a-AlCMK prokaryotic expression vector was constructed and a fusion protein with molecular mass of about 65 kDa was expressed in the E. coli BL21 (DE3). The qRT-PCR was used to analyze the expression pattern of AlCMK gene in different tissues and after MeJA treatment. Meanwhile, the enzyme activity was determined by ELISA kit. The results showed that AlCMK gene was tissue-expressed in different origins and its expression was induced by MeJA, and the results of the enzyme activity assay showed that the AlCMK enzyme activity in different regions was higher in the leaves. The subcellular localization showed that AlCMK was located in the chloroplast. This study provides a reference for further elucidating the biological function of AlCMK gene in terpenoid synthesis pathway in Atractylodes lancea.

Over the past three decades, more and more antisense drugs have been approved for marketing or clinical trails. Antisense technology has become the focus of pharmaceutical research due to its unique advantages in treating diseases and strong clinical development potential. There is a big difference from traditional small molecule chemical drugs, and macromolecular protein biological drugs. Antisense drugs are a very independent drug form. Antisense drugs were initially used to treat diseases with single gene mutations, but recently they have gradually begun to be used for the treatment of common diseases. Rational antisense drug design is crucial for disease treatment based on genetics. This paper reviews the latest progress in the field of action mechanism, chemical modification and delivery strategy of antisense drugs, and analyzes the current intractable problems. It is believed that with the resolution of these problems, the research of antisense drugs can reach a new level.

The carbamoyl phosphate synthase 1 (CPS1) enzyme is involved in the first phase of the urea cycle, providing a prerequisite molecule for pyrimidine synthesis, as well as promoting tumor cell proliferation and growth. Studies have found that CPS1 is highly expressed in a variety of tumors, including colorectal cancer, lung cancer, etc. and its overexpression is related to the poor prognosis of tumors. Thus, small molecules targeted to inhibit the function of CPS1 in tumors may provide therapeutic benefits for cancer patients who overexpress CPS1. In this study, the function of CPS1 was investigated in vitro, and we found that overexpression of CPS1 can enhance the migration ability of colorectal cancer cells HCT15. Here, based upon the existing crystal structure, combined with high-throughput virtual screening, we obtained 8 candidate small molecule compounds. In vitro activity evaluation, we found that compound 3 has good anti-HCT15, HCT116 cell proliferation activity (HCT15, IC₅₀, 7.69 ± 1.10 μmol‧L^-1, HCT116, IC₅₀, 13.53 ± 0.46 μmol‧L^-1). Subsequently, molecular docking and molecular dynamics (MD) simulation analysis showed that, compound 3 could target and inhibit the activity of CPS1. In vitro studies showed that compound 3 could inhibit the migration of HCT15 cells, as well as induced cell cycle arrest and apoptosis. Taken together, this study found that compound 3 is a potential small molecule inhibitor that targets CPS1, which provides the experimental basis and theoretical basis for the development of targeted intervention small molecule therapeutic drugs. Based upon the chemical structure of compound 3, we will shed new light on further optimizing its activity and therapeutic potential, which may provide a therapeutic benefit to the patients with CPS1-related tumors.

With the wide application of stable isotope tracer metabolomics technology, its comprehensive analysis and in-depth mining of data are particularly important, and metabolic flux analysis is one of the main technical means, especially in the study of glucose metabolism. Metabolic flux analysis technology combines isotope tracing with mathematical models to deduce and calculate the metabolic flux between metabolites. The metabolic flux provides more information for research and reflects a dynamic metabolic process more clearly and specifically. This paper reviews the basic process, precautions, and application examples of metabolic flux analysis in glucose metabolism research, and provides a reference for the application of metabolic flux analysis based on stable isotope tracer metabolomics in glucose metabolism research.

Glioblastoma (GBM) is the most common primary brain tumor, which is prone to recurrence and metastasis with poor prognosis. In recent years, immunotherapy has prolonged the survival of patients with GBM, providing a new option for the treatment of GBM. Target selection is very important for immunotherapy. Epidermal growth factor receptor variant Ⅲ (EGFRvⅢ) is highly expressed on the surface of GBM cells in some patients, and EGFRvⅢ was not expressed in normal tissues. EGFRvⅢ are pivotal for the occurrence and progression of GBM, various targeted therapy including immunotherapy is promising to improve the efficacy of GBM. Currently, there are various approaches to target EGFRvⅢ, including humanized monoclonal antibodies, adoptive cell therapies and therapeutic vaccines. In this review, we focus on the preclinical and clinical findings of targeting EGFRvⅢ for GBM.

More and more studies have shown that NOD-like receptor protein 3 (NLRP3) inflammasome has become the regulatory factor of inflammatory response and protective immunity, and the assembly and activation of NLRP3 inflammasomes are closely related to the anti-tumor immunity effect. Depending on the cell type and stimuli, activation of the NLRP3 inflammasome can induce immune cells to become polarized, hyperactive, or pyroptotic, releasing interleukin (IL)-1β and IL-18, which leads to cascade immune or inflammatory responses, and its role in tumor immunity has received extensive attention. Here, we review the mechanisms of the NLRP3 inflammasome enhancing CD8⁺ T cells-mediated anti-tumor immunity by inducing the pyroptosis of tumor cell, the pyroptosis or hyperactive state of dendritic cells (DCs), and the pyroptosis or polarization of the macrophages. Different anti-tumor immune roles of NLRP3 inflammasome activation in tumor cells and immune cells provide new directions for future research and may influence the development of next-generation immunotherapy.

One undescribed diterpenoid acid and six compounds were isolated from the 95% ethanol fraction of Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui resin by using various chromatographic methods, including MCI Gel, Sephadex LH-20, ODS, silica gel and semi-preparative HPLC. The planar structures were identified by spectroscopy methods (1D, 2D NMR, UV, IR, MS, etc.), and the absolute configuration of the new compound was determined by ECD calculation. Compound 1 is a new compound, and compounds 2, 5-7 were isolated from Pinus kesiya var. langbianensis (A.Chev.) Gaussen ex Bui for the first time.