Yuxin Li

Name:

Organization: Northeast Normal University

Department: ChinaInstitute of Genetics and Cytology

Title:

Chemicals
References

Efficient Cancer Regression by a Thermosensitive Liposome for Photoacoustic Imaging-Guided Photothermal/Chemo Combinatorial Therapy

Co-reporter:Yue Cao, Jingwen Yi, Xiaoguang Yang, Lei Liu, Chunlei Yu, Yanxin Huang, Luguo Sun, Yongli Bao, and Yuxin Li

Biomacromolecules August 14, 2017 Volume 18(Issue 8) pp:2306-2306

Publication Date(Web):June 27, 2017

DOI:10.1021/acs.biomac.7b00464

The capacity to specifically destroy cancer cells while avoiding normal tissue is urgently desirable in cancer treatment. Herein, a photothermal-trigger-released system serves as a photoacoustic imaging agent constructed by entrapping diketopyrrolopyrrole-based conjugated polymers and curcumin in a poly(ethylene glycol) (PEG)-protected thermoresponsive liposomal phospholipid bilayer. This lipid nanostructure can improve the bioavailability of hydrophobic agents for photothermal treatment with high efficiency and deliver the anticancer drug curcumin to the tumor site actuated by near-infrared (NIR) irradiation. A significantly enhanced combined therapeutic effect to HepG2 tumor-bearing mice was acquired in contrast to the result of single therapy alone. These liposomes with the capability of photoacoustic imaging, greater EPR-induced accumulation in tumor sites, and hyperthermia ablation for photothermal chemotherapy show potential for photoacoustic imaging-guided photothermal/chemo combined therapeutic applications.

Near-infrared conjugated polymers for photoacoustic imaging-guided photothermal/chemo combination therapy

Co-reporter:Yue Cao;Yannan Wu;Guannan Wang;Jingwen Yi;Chunlei Yu;Yanxin Huang;Luguo Sun;Yongli Bao

Journal of Materials Chemistry B 2017 vol. 5(Issue 27) pp:5479-5487

Publication Date(Web):2017/07/12

DOI:10.1039/C7TB01264K

Conjugated polymers (CPs) with intensive near-infrared (NIR) absorption and high photothermal conversion efficiency (PCE) have emerged as a new generation of photothermal therapy (PTT) and photoacoustic imaging (PAI) agents for cancer therapy. PTT + chemotherapy has been identified as a powerful modality to offer synergistic effects in the destruction and monitoring of cancer tissues. In this study, diketopyrrolopyrrole-based polymers (DPP) were designed through a combination of donor–acceptor moieties. Then, doxorubicin (DOX) and DPP were co-encapsulated in tocopheryl polyethylene-glycol-succinate-cholesterol (TPGS-CHO) copolymers to build a combined theranostic system for tumor treatment. These combined NPs with high PCE (∼50%) and strong (NIR) absorption exhibit excellent real-time photoacoustic imaging detection and synergistic cancer inhibition.

Testes-specific protease 50 promotes cell invasion and metastasis by increasing NF-kappaB-dependent matrix metalloproteinase-9 expression

Co-reporter:Z B Song, J-S Ni, P Wu, Y L Bao, T Liu, M Li, C Fan, W J Zhang, L G Sun, Y X Huang and Y X Li

Cell Death & Disease 2015 6(3) pp:e1703

Publication Date(Web):2015-03-01

DOI:10.1038/cddis.2015.61

The high mortality in breast cancer is often associated with metastatic progression in patients. Previously we have demonstrated that testes-specific protease 50 (TSP50), an oncogene overexpressed in breast cancer samples, could promote cell proliferation and tumorigenesis. However, whether TSP50 also has a key role in cell invasion and cancer metastasis, and the mechanism underlying the process are still unclear. Here we found that TSP50 overexpression greatly promoted cell migration, invasion, adhesion and formation of the stellate structures in 3D culture system in vitro as well as lung metastasis in vivo. Conversely, TSP50 knockdown caused the opposite changes. Mechanistic studies revealed that NF-κB signaling pathway was required for TSP50-induced cell migration and metastasis, and further results indicated that TSP50 overexpression enhanced expression and secretion of MMP9, a target gene of NF-κB signaling. In addition, knockdown of MMP9 resulted in inhibition of cell migration and invasion in vitro and lung metastasis in vivo. Most importantly, immunohistochemical staining of human breast cancer samples strongly showed that the coexpression of TSP50 and p65 as well as TSP50 and MMP9 were correlated with increased metastasis and poor survival. Furthermore, we found that some breast cancer diagnosis-associated features such as tumor size, tumor grade, estrogen receptors (ER) and progesterone receptors (PR) levels, were correlated well with TSP50/p65 and TSP50/MMP9 expression status. Taken together, this work identified the TSP50 activation of MMP9 as a novel signaling mechanism underlying human breast cancer invasion and metastasis.

Four New Alkaloids from the Fermentation Broth of Armillaria mellea

Co-reporter:Yun-Chao Wang;Yu-Wei Zhang;Li-Hua Zheng;Yong-Li Bao;Yin Wu;Chun-Lei Yu;Yan-Xin Huang;Lu-Guo Sun;Yu Zhang;Xiu-Juan Jia;Yu-Xin Li

Helvetica Chimica Acta 2013 Volume 96( Issue 2) pp:330-337

Publication Date(Web):

DOI:10.1002/hlca.201200186

Abstract

Four compounds with similar structures and UV spectra were isolated from the fermentation broth of Armillaria mellea by means of preparative HPLC. Their structures were established as methyl (2S)-1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylate (1), (2S)-1-[2-(furan-2-yl)-2-oxoethyl]-5-oxopyrrolidine-2-carboxylic acid (2), 1-[2-(furan-2-yl)-2-oxoethyl]pyrrolidin-2-one (3) and 1-[2-(furan-2-yl)-2-oxoethyl]piperidin-2-one (4) on the basis of their 1D- and 2D-NMR, and HR-MS data. The absolute configurations of compounds 1 and 2 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) data. Additionally, four known compounds, 5–8, were also isolated.

A dual-targeting hybrid platinum(IV) prodrug for enhancing efficacy

Co-reporter:Haihua Xiao, Lesan Yan, Yu Zhang, Ruogu Qi, Wenliang Li, Rui Wang, Shi Liu, Yubin Huang, Yuxin Li and Xiabin Jing

Chemical Communications 2012 vol. 48(Issue 87) pp:10730-10732

Publication Date(Web):26 Sep 2012

DOI:10.1039/C2CC34297A

A multifunctional hybrid platinum(IV) prodrug, which consists of both the mitochondria-targeting drug DCA and the DNA-crosslinking drug cisplatin, was synthesized and tethered to a carrier polymer to further self-assemble into micelles for intracellular delivery.

Juglanthraquinone C, a novel natural compound derived from Juglans mandshurica Maxim, induces S phase arrest and apoptosis in HepG2 cells

Co-reporter:Yao Yao;Yu-Wei Zhang;Lu-Guo Sun;Biao Liu;Yong-Li Bao;Hua Lin;Yu Zhang

Apoptosis 2012 Volume 17( Issue 8) pp:832-841

Publication Date(Web):2012 August

DOI:10.1007/s10495-012-0722-5

Juglanthraquinone C (1,5-dihydroxy-9,10-anthraquinone-3-carboxylic acid, JC), a naturally occurring anthraquinone isolated from the stem bark of Juglans mandshurica, shows strong cytotoxicity in various human cancer cells in vitro. Here, we first performed a structure–activity relationship study of six anthraquinone compounds (JC, rhein, emodin, aloe-emodin, physcion and chrysophanol) to exploit the relationship between their structural features and activity. The results showed that JC exhibited the strongest cytotoxicity of all compounds evaluated. Next, we used JC to treat several human cancer cell lines and found that JC showed an inhibitory effect on cell viability in dose-dependent (2.5–10 μg/ml JC) and time-dependent (24–48 h) manners. Importantly, the inhibitory effect of JC on HepG2 (human hepatocellular carcinoma) cells was more significant as shown by an IC50 value of 9 ± 1.4 μg/ml, and 36 ± 1.2 μg/ml in L02 (human normal liver) cells. Further study suggested that JC-induced inhibition HepG2 cell proliferation was associated with S phase arrest, decreased protein expression of proliferation marker Ki67, cyclin A and cyclin-dependent kinase (CDK) 2, and increased expression of cyclin E and CDK inhibitory protein Cip1/p21. In addition, JC significantly triggered apoptosis in HepG2 cells, which was characterized by increased chromatin condensation and DNA fragmentation, activation of caspase-9 and -3, and induction of a higher Bax/Bcl2 ratio. Collectively, our study demonstrated that JC can efficiently inhibit proliferation and induce apoptosis in HepG2 cells.

Contribution of Active Site Residues to Substrate Hydrolysis by USP2: Insights into Catalysis by Ubiquitin Specific Proteases

Co-reporter:Wanfang Zhang, Traian Sulea, Limei Tao, Qizhi Cui, Enrico O. Purisima, Ratsavarinh Vongsamphanh, Paule Lachance, Viktoria Lytvyn, Hongtao Qi, Yuxin Li, and Robert Ménard

Biochemistry 2011 Volume 50(Issue 21) pp:

Publication Date(Web):May 4, 2011

DOI:10.1021/bi101958h

The ubiquitin-specific protease (USP) structural class represents the largest and most diverse family of deubiquitinating enzymes (DUBs). Many USPs assume important biological roles and emerge as potential targets for therapeutic intervention. A clear understanding of USP catalytic mechanism requires a functional evaluation of the proposed key active site residues. Crystallographic data of ubiquitin aldehyde adducts of USP catalytic cores provided structural details on the catalytic triad residues, namely the conserved Cys and His, and a variable putative third residue, and inferred indirect structural roles for two other conserved residues (Asn and Asp), in stabilizing via a bridging water molecule the oxyanion of the tetrahedral intermediate (TI). We have expressed the catalytic domain of USP2 and probed by site-directed mutagenesis the role of these active site residues in the hydrolysis of peptide and isopeptide substrates, including a synthetic K48-linked diubiquitin substrate for which a label-free, mass spectrometry based assay has been developed to monitor cleavage. Hydrolysis of ubiquitin-AMC, a model substrate, was not affected by the mutations. Molecular dynamics simulations of USP2, free and complexed with the TI of a bona fide isopeptide substrate, were carried out. We found that Asn271 is structurally poised to directly stabilize the oxyanion developed in the acylation step, while being structurally supported by the adjacent absolutely conserved Asp575. Mutagenesis data functionally confirmed this structural role independent of the nature (isopeptide vs peptide) of the bond being cleaved. We also found that Asn574, structurally located as the third member of the catalytic triad, does not fulfill this role functionally. A dual supporting role is inferred from double-point mutation and structural data for the absolutely conserved residue Asp575, in oxyanion hole formation, and in maintaining the correct alignment and protonation of His557 for catalytic competency.

Anthracene and Anthraquinone Derivatives from the Stem Bark of Juglans mandshuricaMaxim.

Co-reporter:Hua Lin;Yu-Wei Zhang;Li-Hua Zheng;Xiang-Ying Meng;Yong-Li Bao;Yin Wu;Chun-Lei Yu;Yan-Xin Huang;Yu-Xin Li

Helvetica Chimica Acta 2011 Volume 94( Issue 8) pp:

Publication Date(Web):

DOI:10.1002/hlca.201000462

Abstract

One new anthracene derivative, juglanthracenoside A (1), two new anthraquinones, juglanthraquinone A (2) and juglanthraquinone B (3), along with a new naturally occurring anthraquinone, 9,10-dihydro-4,8-dihydroxy-9,10-dioxoanthracene-2-carboxylic acid (4), have been isolated from the stem bark of Juglans mandshurica. Their structures were established by detailed spectroscopic analysis and comparison of the NMR data with those of related compounds. Compound 1 displayed noticeable antioxidant activity in both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical-scavenging assays, while compound 4 showed strong cytotoxicity against HepG2, SGC7901, HCT-8, and A549 cell lines in vitro.

Simultaneous Determination of Lathyrane Diterpenoids by NPLC-DAD in the Seeds of Euphorbia lathyris and “ZI-JIN-DING” Pastille

Co-reporter:Hong-Yan Zhu;Xiang-Ying Meng;Yong-Li Bao;Chun-Lei Yu;Yin Wu

Chromatographia 2010 Volume 71( Issue 7-8) pp:617-622

Publication Date(Web):2010 April

DOI:10.1365/s10337-010-1482-4

A novel, simple and specific normal-phase liquid chromatography (NPLC) method has been developed for simultaneous determination of the four lathyrane diterpenoids, lathyrol-5,15-diacetate-3-benzoate (1, L3), lathyrol-5,15-diacetate-3,7-dibenzoate (2, L2), Δ6,17-epoxide-5,15-diacetate-3-phenylacetate (3, L1), lathyrol-5,15-diacetate-3-nicotinate (4, L8) in the hexane extract of the seeds of Euphorbia lathyris and “ZI-JIN-DING” pastille. The method showed good linearity for the four analytes (r2 > 0.99), the intra-day and inter-day variations (RSD) were less than 3%, and the recoveries ranged from 99.4 to 100.6%. This method was successfully used to determine the four lathyrane diterpenoids in the seeds of Euphorbia lathyris and “ZI-JIN-DING” pastille, and could be applied for their quality control.

Organic–inorganic hybrid based on the molybdenum tellurite

Co-reporter:Ying Liu, Yu-Xin Li, Shi-Wei Zhang, Hong-Mei Ji, Rui-Ge Cao, Shu-Xia Liu

Journal of Molecular Structure 2009 Volume 921(1–3) pp:114-117

Publication Date(Web):17 March 2009

DOI:10.1016/j.molstruc.2008.12.058

Two novel organic–inorganic hybrid molybdenum tellurites [M2(bpy)2][Te2Mo6O24] (M = Cu(II) 1, M = Ni(II) 2; bpy = 2,2′-bipyridine) have been hydrothermally synthesized and characterized by the elemental analyses, IR spectra, TG analyses, X-ray powder diffraction and single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system, space group P-1, with a = 7.7824(5) Å, b = 9.7506(6) Å, c = 12.4885(8) Å, α = 98.867(1)°, β = 107.027(1)°, γ = 102.425(1)° and Z = 2. Compound 2 crystallizes in the triclinic system, space group P-1, with a = 7.7928(5) Å, b = 9.7436(6) Å, c = 12.4764(8) Å, α = 98.904(1)°, β = 107.211(1)°, γ = 102.192(1)° and Z = 2. Compounds 1 and 2 are iso-structural, and both exhibit interesting 1-D ribbons bridged by metal-organic complex moieties [M (bpy)]2+ (M = Cu and Ni). Furthermore, the three-dimensional supramolecular architectures of compounds 1 and 2 are further formed by π–π stacking interactions of 2,2-bpy groups.

Comparative study of paclitaxel physically encapsulated in and chemically conjugated with PEG-PLA

Co-reporter:Xiaoyi Xu;Xuefei Zhang;Xiuhong Wang;Xiabin Jing

Polymers for Advanced Technologies 2009 Volume 20( Issue 11) pp:843-848

Publication Date(Web):

DOI:10.1002/pat.1341

Abstract

Paclitaxel-loaded poly(ethylene glycol)-b-poly(l-lactide (LA)) (PEG-PLA) micelles were prepared by two methods. One is physical encapsulation of paclitaxel in micelles composed of a PEG-PLA block copolymer and the other is based on a PEG-PLA–paclitaxel conjugate, abbreviated as “conjugate micelles”. Their physicochemical characteristics, e.g. critical micelle concentration (CMC), morphology, and micelle size distribution were then evaluated by means of fluorescence spectroscopy, scanning electron microscopy (SEM), and dynamic light scattering (DLS). The results show that the CMC of PEG-PLA–paclitaxel and PEG-PLA are 6.31 × 10⁻⁴ and 1.78 × 10⁻³ g L⁻¹, respectively. Both micelles assume a spherical shape with comparable diameters and have unimodal size distribution. Moreover, invitro drug delivery behavior was studied by high performance liquid chromatography (HPLC). The antitumor activity of the paclitaxel-loaded micelles against human liver cancer H7402 cells was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. The conjugate micelles show a lower burst release during the initial stage and higher accumulative release amount of paclitaxel after a period of time while the encapsulated ones behave in the opposite way. Both the paclitaxel-loaded micelles showed comparable anticancer efficacy with the free drug. Copyright © 2008 John Wiley & Sons, Ltd.

Components of Essential Oils in Different Parts of Daucus carota L. var. sativa Hoffm1

Co-reporter:Yin WU, Ze-Li XU, Hong-jun LI, Xiang-ying MENG, Yong-li BAO, Yu-xin LI

Chemical Research in Chinese Universities 2006 Volume 22(Issue 3) pp:328-334

Publication Date(Web):May 2006

DOI:10.1016/S1005-9040(06)60109-8

The components of the essential oils obtained from different parts of Daucus carota L. var. sativa Hoffm were analyzed. The percentages of the essential oils extracted are 0.27% (ml/100 g material) for the flowers, 0.07% for the stems and leaves and 0.01% for the roots. Fifty-four, Sixty-six and Thirty-three compounds were, respectively, separated and identified from the flowers, the stems and leaves and the roots, among which unsaturated alkene compounds are thirty-nine, thirty-nine and twenty-one, respectively, accounting in turn for up to 90.21%, 90.49% and 72.65% of the total essential oils. Because alkene compounds have double bonds that are easily oxidized, it can be inferred that the components of the essential oils in the different parts of Daucus carota L. var. sativa Hoffm should show an activity of the anti-formation of free radicals to some extent.

The catalytic triad of testes-specific protease 50 (TSP50) is essential for its function in cell proliferation

Co-reporter:Zhen Bo Song, Biao Liu, Yu Yin Li, Ping Wu, Yong Li Bao, Yan Xin Huang, Yin Wu, Lu Guo Sun, Chun Lei Yu, Ying Sun, Li Hua Zheng, Yu Xin Li

Cellular Signalling (October 2014) Volume 26(Issue 10) pp:2266-2275

Publication Date(Web):1 October 2014

DOI:10.1016/j.cellsig.2014.07.012

•The catalytic triad of TSP50 is required for its function in cell proliferation.•Mutant of the catalytic triad abolishes the enzyme activity of TSP50.•The three mutants inhibit the interaction between TSP50 and NF-κB:IκBα complex.•TSP50 can cleave IκBα protein directly as a new protease.Testes-specific protease 50 (TSP50) is a novelly identified pro-oncogene and it shares a similar enzymatic structure with many serine proteases. Our previous results suggested that TSP50 could promote tumorigenesis through degradation of IκBα protein and activating NF-κB signaling, and the threonine mutation in its catalytic triad could depress TSP50-mediated cell proliferation. However, whether the two other residues in the catalytic triad of TSP50 play a role in maintaining protease activity and tumorigenesis, and the mechanisms involved in this process remain unclear. Here, we constructed and characterized three catalytic triad mutants of TSP50 and found that all the mutants could significantly depress TSP50-induced cell proliferation and colony formation in vitro and tumor formation in vivo, and the aspartic acid at position 206 in the catalytic triad played a more crucial role than threonine and histidine in this process. Mechanistic studies revealed that the mutants in the catalytic triad abolished the enzyme activity of TSP50, but did not change the cellular localization. Furthermore, our data indicated that all the three mutants suppressed activation of NF-κB signal by preventing the interaction between TSP50 and the NF-κB:IκBα complex. Most importantly, we demonstrated that TSP50 could interact with IκBα protein and cleave it directly as a new protease in vitro.

Identification and characterization of human ARIP2 and its relation to breast cancer

Co-reporter:Zhan Dong Li, Yin Wu, Yong Li Bao, Chun Lei Yu, Li Li Guan, Yue Zeng Wang, Xiang Ying Meng, Yu Xin Li

Cytokine (May 2009) Volume 46(Issue 2) pp:251-259

Publication Date(Web):1 May 2009

DOI:10.1016/j.cyto.2009.02.009

Activin, a member of the TGF-β superfamily, inhibits the proliferation of breast cancer cells. Activin interacts with its type I and type II receptors to induce phosphorylation of intracellular signaling molecules known as Smads. Previous studies showed that mouse ARIP2 can reduce activin signaling by interacting with activin type II receptors (ActRIIs); however, the activity of ARIP2 in breast cancer is still unclear. In this study, we used RT-PCR to obtain a human homologue of mouse ARIP2, human activin receptor-interacting protein 2 (hARIP2). Like murine ARIP2, hARIP2 has a PDZ domain in its NH2-terminal region and can interact specifically with ActRIIs. Overexpression of hARIP2 reduced activin-induced transcriptional activity and enhanced cell proliferation and colony formation in human breast adenocarcinoma MCF-7 cells and MDA-MB-231 cells. However, down-regulation of hARIP2 expression by RNAi enhanced activin-induced transcriptional activity and reduced cell proliferation and colony formation. Immunohistochemistry revealed that hARIP2 was expressed more frequently and much more intensely in malignant breast tissues such as simple carcinoma, invasive ductal carcinoma and mucinous adenocarcinoma than in benign hyperplasia or fibroadenoma cases. These results suggest that hARIP2 is a putative growth-promoting factor involved in breast tumorigenesis and tumor development.

Maspin inhibits macrophage phagocytosis and enhances inflammatory cytokine production via activation of NF-κB signaling

Co-reporter:Yimeng Wang, Luguo Sun, Zhenbo Song, Danfeng Wang, Yongli Bao, Yuxin Li

Molecular Immunology (February 2017) Volume 82() pp:94-103

Publication Date(Web):1 February 2017

DOI:10.1016/j.molimm.2016.12.021

•Tumor suppressor Maspin induces partial macrophage (Mφ) M1 polarization.•Maspin inhibits Mφ phagocytosis, and decreases the expression of MR and Dectin-1.•Maspin increases Mφ expressing inflammatory cytokines and iNOS, and downregulates Arg-1.•Maspin regulates Mφ function partially due to the activation of NF-κB signaling.Maspin (mammary serine protease inhibitor) is a non-inhibitory member of the serine protease inhibitor superfamily and a tumor suppressor in several cancers due to its ability to inhibit cell invasion, angiogenesis, and promote apoptosis. However, its immunomodulatory function remains largely unexplored. Thus, we explored the potential link between Maspin and macrophage function, first evaluating the regulatory effects of conditioned medium (CM) of a Maspin-overexpressing CHO cell strain on mouse peritoneal macrophage phagocytosis and cytokine secretion. Next, we used a transwell co-culture system and recombinant Maspin (rMaspin) to confirm the effects of Maspin on macrophages, and attempted to clarify the underlying mechanisms. We found that irrespective of CM, rMaspin or co-culture of Maspin-overexpressing cells with macrophages impaired macrophages phagocytosing Saccharomyces cerevisiae. Furthermore, q-RT-PCR or ELISA confirmed increased IL-1β, TNF-α, IFN-γ, IL-6, IL-12, IL-10, and M1 marker iNOS production in macrophages after Maspin stimulation, but TGF-β and M2 marker Arg-1 production were suppressed. Western blot showed activated NF-κB signaling in Maspin-stimulated macrophages; upregulated cytokines were lowered, and impaired phagocytosis recovered after blocking NF-κB signaling with PDTC. Thus, Maspin mildly inhibited phagocytic activity, but markedly enhanced inflammatory cytokine production and likely skewed macrophages towards M1 polarization, partially due to activation of NF-κB signaling. These results reveal a novel biological function of Maspin in modulating macrophage activity and may open a new avenue for Maspin-based tumor therapy.Download high-res image (131KB)Download full-size image

A novel conformational B-cell epitope prediction method based on mimotope and patch analysis

Co-reporter:Pingping Sun, Jialiang Qi, Yizhu Zhao, Yanxin Huang, Guifu Yang, Zhiqiang Ma, Yuxin Li

Journal of Theoretical Biology (7 April 2016) Volume 394() pp:102-108

Publication Date(Web):7 April 2016

DOI:10.1016/j.jtbi.2016.01.021

•A novel epitope prediction method based on amino acid pairs and patch analysis.•Predict epitopes based on AAPs from mimotopes and the surface patch.•Gives out the sensitivity of 0.53, the specificity of 0.77, the ACC of 0.75•Comparing with other methods, the sensitivity of the new method all has improvement.A B-cell epitope is a group of residues on the surface of an antigen that stimulates humoral immune responses. Identifying B-cell epitopes is important for effective vaccine design. Predicting epitopes by experimental methods is expensive in terms of time, cost and effort; therefore, computational methods that have a low cost and high speed are widely used to predict B-cell epitopes. Recently, epitope prediction based on random peptide library screening has been viewed as a promising method. Some novel software and web-based servers have been proposed that have succeeded in some test cases. Herein, we propose a novel epitope prediction method based on amino acid pairs and patch analysis. The method first divides antigen surfaces into overlapping patches based on both radius (R) and number (N), then predict epitopes based on Amino Acid Pairs (AAPs) from mimotopes and the surface patch. The proposed method yields a mean sensitivity of 0.53, specificity of 0.77, ACC of 0.75 and F-measure of 0.45 for 39 test cases. Compared with mimotope-based methods, patch-based methods and two other prediction methods, the sensitivity of the new method offers a certain improvement. Our findings demonstrate that this proposed method was successful for patch and AAPs analysis and allowed for conformational B-cell epitope prediction.

N-Benzoyl-12-nitrodehydroabietylamine-7-one, a novel dehydroabietylamine derivative, induces apoptosis and inhibits proliferation in HepG2 cells

Co-reporter:Ling-Ying Lin, Yong-Li Bao, Yong Chen, Lu-Guo Sun, Xiao-Guang Yang, Biao Liu, Zhong-Xiang Lin, Yu-Wei Zhang, Chun-Lei Yu, Yin Wu, Yu-Xin Li

Chemico-Biological Interactions (30 August 2012) Volume 199(Issue 2) pp:63-73

Publication Date(Web):30 August 2012

DOI:10.1016/j.cbi.2012.06.002

The high biological activity of dehydroabietylamine derivatives has been reported previously. In this study, we aimed to screen 73 dehydroabietylamine derivatives as potential candidate inhibitors in liver cancer cells. Initially, the compounds structural activity relationship analysis was explored and N-benzoyl-12-nitrodehydroabietylamine-7-one (compound 81) was shown to have significant growth inhibitory activity in the human liver carcinoma cell line, HepG2. Further research into the anti-proliferative effect on HepG2 cells mediated by compound 81 was undertaken. The results suggest that compound 81 effectively induced apoptosis in HepG2 cells characterized by nuclear staining of DAPI, TUNEL assay and the activation of caspase-3. A decreased level of anti-apoptotic protein Bcl-2 and increased apoptotic Bax were also observed. Furthermore, Ki-67 protein staining and the BrdU incorporation assay showed that compound 81 significantly inhibited the proliferation of HepG2 cells. Cell cycle components analysis found that expression of cyclin D1 and cyclin B1 was reduced in HepG2 cells with compound 81 treatment, whereas the content of p21Waf1/Cip1 was increased. Taken together, our data indicate that compound 81 induces apoptosis and inhibits proliferation in HepG2 cells, and may be a promising candidate in the development of a novel class of antitumor agents.Highlights► We investigated the antitumor activities of 73 dehydroabietylamine derivatives. ► We explored the structure–antitumor activity relationship of 73 compounds. ► We identified a novel dehydroabietylamine derivative as a potential antitumor agent. ► Compound 81 can induce apoptosis and inhibit proliferation in HepG2 cells.

Periplogenin induces necroptotic cell death through oxidative stress in HaCaT cells and ameliorates skin lesions in the TPA- and IMQ-induced psoriasis-like mouse models

Co-reporter:Wen-Jing Zhang, Zhen-Bo Song, Yong-Li Bao, Wen-liang Li, Xiao-Guang Yang, Qi Wang, Chun-Lei Yu, Lu-Guo Sun, Yan-Xin Huang, Yu-Xin Li

Biochemical Pharmacology (1 April 2016) Volume 105() pp:66-79

Publication Date(Web):1 April 2016

DOI:10.1016/j.bcp.2016.02.001

A dual-targeting hybrid platinum(IV) prodrug for enhancing efficacy

Co-reporter:Haihua Xiao, Lesan Yan, Yu Zhang, Ruogu Qi, Wenliang Li, Rui Wang, Shi Liu, Yubin Huang, Yuxin Li and Xiabin Jing

Chemical Communications 2012 - vol. 48(Issue 87) pp:NaN10732-10732

Publication Date(Web):2012/09/26

DOI:10.1039/C2CC34297A

Near-infrared conjugated polymers for photoacoustic imaging-guided photothermal/chemo combination therapy

Co-reporter:Yue Cao, Yannan Wu, Guannan Wang, Jingwen Yi, Chunlei Yu, Yanxin Huang, Luguo Sun, Yongli Bao and Yuxin Li