Latest ArticlesThe study was designed to test the role of 5, 2', 4'-trihydroxy-6, 7, 5'-trimethoxy flavone nanoparticle (TTF1-NP) on lipopoiysaccharide (LPS)-induced inflammatory response, and to explore the anti-inflammatory mechanism in human hepatocellular carcinoma cells. Inflammatory responses were induced in human hepato-cellular carcinoma HepG2 cells with LPS; Proliferation effect of TTF1-NP in LPS-stimulated HepG2 cells were detected by MTT assay; The expression of TLR4, AKT/mTOR signaling related proteins and IL-6 were detected by Western blot assay. The results showed that TTF1-NP inhibited the proliferation of HepG2 cells induced by LPS in a dose-dependent manner; TTF1-NP inhibited the expression of TLR4, the activation of AKT and mTOR, and expression of IL-6 in a dose-dependent manner; TTF1-NP inhibited the activation of AKT/mTOR signaling pathway and TLR4 proteins leading to suppression of IL-6 expression in HepG2 cells stimulated by insulin. These results suggest that TTF1-NP inhibited inflammatory responses from LPS treatment with a potential mechanisms in the inhibition of AKT/mTOR pathway.
Charge-reversal nanocarrier was constructed to enhance lysosomal escape and improve an-titumor effect. We synthesized the cholesterol-polyethyleneimine-hexahydrophthalic anhydride (Chol-PEI-HHPA) polymer and characterized by 1H NMR. The charge-reversal liposomes (Lipo-HHPA) were synthesized and the hematoporphyrin monomethyl ether (HMME) was loaded. pH-triggered charge conversion was determined at different pH values. The lysosomal escape and cytotoxicity of the Lipo-HHPA were evaluated in MCF-7 cells. The Lipo-HHPA was uniform with an average particle size of 102 nm. Upon the irradiation of ultrasound, burst release of HMME could be observed. The zeta potential of Lipo-HHPA changed sharply from negative (-23.5 mV) to positive (+21.2 mV) over the pH range of 7.4-4.5. In the cellular uptake experiment, the lysosomal escape of Lipo-HHPA was observed. HMME loaded Lipo-HHPA displayed obviously enhanced cytotoxicity towards MCF-7 cells. These results indicate that the charge-reversal liposomes hold a great potential in improving the cytotoxicity and antitumor effect.
Microfluidics is a technology that involves the use of micro-nanoscale pipelines to manipulate fluid mixing. Precise control of the mixing process of laminar flows or liquid droplets by using microfluidics will contribute to the preparation of nanoparticles, which are difficult to be achieved by the conventional methods. Based on the progress in delivery systems of nanoparticulate drug, we provide a summary to introduce the applications of microfluidics in construction of nanoparticulate drug delivery system such as liposomes, polymer nanoparticles and hybrid nanoparticles, and analyze the assembling mechanisms of different nanostructures by using microfluidic precise control. This review will provide a reference in utilization of microfluidic technology more scientifically and reasonably.
The study aims to establish an LC-MS/MS method for the determination of S-(+)-ibuprofen (S-IBP) and R-(-)-ibuprofen (R-IBP), which may be used subsequently to investigate the pharmacokinetics of ibuprofen enantiomers in healthy Chinese volunteers. Naproxen was used as an internal standard. The separation was achieved on a Chiralpak AD-3R column (4.6 mm×150 mm, 3.0 μm) with a mobile phase consisting of acetonitrile/0.01% formic acid aqueous solution (40:60) at a flow rate of 750 μL·min-1 within 23.0 min. Naproxen and the internal standard were measured by a triple-quadrupole mass spectrometer in negative electron electronic spray ion (ESI) mode using multiple reaction monitoring (MRM). The extracted ions monitored following MRM transitions were m/z 205.1→161.0 for ibuprofen enantiomers and m/z 229.1→185.0 for the internal standard naproxen. Plasma samples were pretreated through methanol precipitation. The calibration curve of S-IBP and R-IBP in human plasma was linear over the concentration rang of (0.05-30.00) μg·mL-1. The lower limit of quantitation was 0.05 μg·mL-1. The intra-and inter-run precisions of S-IBP at three quality control levels were within 2.2%-4.2%, the relative deviation of the assay was within -12.0%-13.0%. The intra-and inter-run precisions of R-IBP at three quality control levels were within 2.0%-8.2%, the relative deviation of the assay was within -11.5%-10.6%. The plasma samples were stable at room temperature (25℃) for 6 h, at -30℃ for 47 days and during three freeze-thaw cycles. The method was proved to be convenient, accurate and sensitive, and suitable for the pharmacokinetics study of ibuprofen enantiomers in healthy Chinese volunteers after a single oral dose of 300 mg ibuprofen extended-release capsule.
The protein-protein interactions play an important role in life science. At present, many methods are developed with preferences of the amino acid residues, which do not offer the relative spatial information for the residue groups. However, the spatial information for the residue groups is important in the design of the protein-protein interactions. We proposed a new model, which is named 'tri-prism' model, by deep mining the existing protein-protein interaction patterns and refining the preference and the relative spatial information for the combination pairs of the residue groups. The model not only provided the preferences, but also offered the relative spatial information for the triplets combination pairs of the residue groups. The model was able to analyze the triplets combination pairs of the residue groups based on the preference factor, amino acid composition, and protein secondary structure. The model was applied to the interface of the PD-1/PD-L2 protein. According to the diversity characters of the composition and the spatial information between the combination pairs of the residue groups at the interface of the PD-1/PD-L2 protein and the predicted ones, we put forward the suggestions for the mutations of the residues, which offered a new view in the study of protein-protein interactions.
Soluble resistance-related calcium-binding protein, SORCIN, is a 22 kDa calcium binding protein with "penta-EF hand", which participates in the regulation of intracellular calcium homeostasis in cells. SORCIN is highly expressed in many tissues such as hearts and brains. It is overexpressed in some of cancer tissues as well. Recently, a large amount of clinical data showed that SORCIN was closely related to drug resistance in cancer. Meanwhile, basic research found that SORCIN participates in the formation of multidrug resistance (MDR) and is related to severity and poor prognosis of tumors. Moreover, it may also regulate MDR induced by ATP-binding cassette transporters. Therefore, SORCIN is expected to become a new target for diagnosis and treatment of MDR. The present review summarizes recent progress in SORCIN study and its effect on MDR.
Hepatocellular carcinoma (HCC) is the most common liver cancer, which is also the second leading cause of death in cancer. With the development of molecular biology and technology, gene therapy has become a new potential method to treat the cancer. As a viral gene-delivery system, the adeno-associated virus (AAV) is the most promising delivery vehicle for its high efficiency of infection, low pathogenicity and low immunogenicity. However, AAV has a wide range of host that may lead to side effects. Targeted gene therapy can achieve site-specific and high efficient gene expression, which avoids toxicity of systemic and non-targeted gene expression to improve the safety and efficacy of gene therapy. In this review, we provide an overview of the pathogenesis of HCC and the characteristics of AAV. Moreover, we discuss the targeting strategies currently employed in the gene therapy for HCC with a focus on targeting the transductional, transcriptional and posttranscriptional levels. New strategies are proposed for improving the quality of life and survival rate of patients with HCC.
Signal transducers and activators of transcription (STAT3) is an important member of the family of signal transducers and activators of transcription, which plays a dual role in signaling and initiating gene transcription in cells. Numerous studies have demonstrated constitutive activation of STAT3 in a wide variety of human tumors. There is strong evidence to suggest that aberrant STAT3 signaling promotes initiation and progression of human cancers by either inhibition of apoptosis or induction of cell proliferation, angiogenesis, invasion, metastasis, inflammation and immunosuppression. At present, some specific small molecule inhibitors have been developed to target STAT3. However, no drugs have been used in the clinical stage. The identification and development of novel drugs that can target deregulated STAT3 activation effectively remains an important scientific and clinical challenge. This article provides a summary on progress about STAT3 in tumor genesis and new inhibitors of STAT3.
Five triterpene saponins were isolated from the aqueous extract of the leaves of Panax notoginseng (Burk.) F.H.Chen via various chromatographic approaches, including HPD-100 macroporous resin, silica gel, reverse phase C18 and so on. Spectroscopic and chemical methods were used to elucidated their structures, which were determined to be 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-12β, 23(R)-epoxydammara-24-ene-3β, 6α, 20(S)-triol 20-O-α-L-arabinofuranosyl-(1→6)-β-D-glucopyranoside (1), 3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-12β, 23(R)-epoxydammara-24-ene-3β, 6α, 20(S)-triol 20-O-α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (2), notoginsenoside FP2 (3), gypenoside Ⅸ (4), ginsenoside Rg1 (5). Compounds 1 and 2 are new compounds and named as notoginsenoside Fh8 and notoginsenoside Fh9.
The anaphase promoting complex (APC) regulates cell cycle progression by forming two functionally distinct E3 ubiquitin ligase complexes, APCCdc20 activated by cell division cycle protein 20 (Cdc20) and APCCdh1 activated by Cdc20 homologue 1 (Cdh1), respectively. Cdc20 and Cdh1 have different functions in the occurrence and development of the tumor. Cdc20 is a cancer promoter while Cdh1 suppresses tumorigenesis. Emerging evidence has begun to reveal that Cdc20 has positive functions in tumorigenesis, the overexpression of Cdc20 has been observed in many cancers. Currently, Cdc20 inhibitors, mostly non-specific inhibitors except apcin, not only block the combination between Cdc20 and APC, also block the combination between Cdh1 and APC, which leads to a poor selectivity. In this paper, the Cdc20 role in the development and process of cancers and its inhibitors are reviewed.