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ABSTRACT: Aim:Curcumin has shown promising anticancer activity, which relies on its inhibition on NF-κB pathway. In this study, we characterized the pharmacological profile of a novel curcumin analog P1 and elucidate the related mechanisms.Methods:HEK293/NF-κB cells, stably transfected with an NF-κB-responsive luciferase reporter plasmid, were generated for high-throughput screen (HTS). Eight cancer cell lines, including PC3, COLO 205, HeLa cells etc. were tested. Cell viability was assessed using the sulforhodamine B (SRB) assays. Cell apoptosis was evaluated using FACS, immunocytochemistry, and Western blotting. H2-DCFDA and MitoSOX Red were used to detect cellular and mitochondrial reactive oxygen species (ROS). The mitochondrial function was evaluated using mitochondrial oxygen consumption assay.Results:P1, a tropinone curcumin, was found in HTS targeting the NF-κB pathway. Its IC50 value in inhibition of TNF-α-induced NF-κB activation was 0.8 μmol/L, whereas its IC50 values in inhibiting the growth of A549 and HeLa cells were 1.24 and 0.69 μmol/L, respectively, which was 20- to 30-fold more potent than curcumin. The inhibition of P1 on the NF-κB pathway was further addressed in HeLa cells: The compound up to 10 μmol/L did not affect the binding of NF-κB to DNA, but markedly inhibited NF-κB nuclear translocation, IκB degradation and IκB kinase phosphorylation. The compound (1 and 3 μmol/L) concentration-dependently induced ROS generation, whereas curcumin up to 20 μmol/L had no effect. P1-induced ROS generation was mainly localized in mitochondria, and reversed by NAC. Moreover, the compound significantly enhanced TNF-α-induced apoptosis.Conclusion:P1 is a novel curcumin analog with potent anticancer activities, which exerts a distinct inhibition on the NF-κB pathway.
Acta Pharmacologica Sinica 04/2013; · 1.95 Impact Factor
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ABSTRACT: To identify a novel coumarin analogue with the highest anticancer activity and to further investigate its anticancer mechanisms.
The viability of cancer cells was investigated using the MTT assay. The cell cycle progression was evaluated using both flow cytometric and Western blotting analysis. Microtubule depolymerization was observed with immunocytochemistry in vivo and a tubulin depolymerization assay in vitro. Apoptosis was demonstrated using Annexin V/Propidium Iodide (PI) double-staining and sub-G(1) analysis.
Among 36 analogues of coumarin, 6-chloro-4-(methoxyphenyl) coumarin showed the best anticancer activity (IC(50) value about 200 nmol/L) in HCT116 cells. The compound had a broad spectrum of anticancer activity against 9 cancer cell lines derived from colon cancer, breast cancer, liver cancer, cervical cancer, leukemia, epidermoid cancer with IC(50) value of 75 nmol/L-1.57 μmol/L but with low cytotocitity against WI-38 human lung fibroblasts (IC(50) value of 12.128 μmol/L). The compound (0.04-10 μmol/L) induced G(2)-M phase arrest in HeLa cells in a dose-dependent manner, which was reversible after the compound was removed. The compound (10-300 μmol/L) induced the depolymerization of purified porcine tubulin in vitro. Finally, the compound (0.04-2.5 μmol/L) induced apoptosis of HeLa cells in dose- and time-dependent manners.
6-Chloro-4-(methoxyphenyl) coumarin is a novel microtubule-targeting agent that induces G(2)-M arrest and apoptosis in HeLa cells.
Acta Pharmacologica Sinica 03/2012; 33(3):407-17. · 1.95 Impact Factor
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ABSTRACT: The anomeric mixture of a series of O-galactolipid derivatives is revealed to be more toxic against several cancer cell lines than their either single component with the pure α- or β-configuration. This interesting phenomenon has been confirmed on pairs of synthesized O-galactosyl anomers bearing length-varied alkyl chains at the lipid end. Furthermore, the most potent mixture was determined inoffensive to a normal cell line tested.
Bioorganic & medicinal chemistry letters 03/2012; 22(5):2030-2. · 2.65 Impact Factor
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ABSTRACT: Two new prenylgermacrane-type diterpenoids, lobophytumins A and B (1 and 2), two new prenyleudesmane-type diterpenoids, lobophytumins C and D (3 and 4), and two new spatane-type diterpenoids, lobophytumins E and F (5 and 6), were isolated from the Hainan soft coral Lobophytum cristatum Tixier-Durivault. Their structures, including relative configuration, were elucidated by detailed analysis of spectroscopic data and by comparison with related known compounds. In addition, the absolute configuration of lobophytumin C (3) was tentatively assigned by comparing its specific rotation with that of the closely related model compound (-)-β-selinene (8). On the basis of biogenetic considerations, the absolute configurations of lobophytumins A, B, and D-F were also tentatively suggested. This is the first report of spatane-type diterpenoids from a soft coral source. The present work supports Faulkner's proposal of prenylgermacrene as the precursor of many diterpenes. In a bioassay, lobophytumins C and D (3 and 4) showed weak in vitro cytotoxicities against the tumor cell lines A-549 and HCT-116.
Journal of Natural Products 09/2011; 74(10):2089-94. · 3.13 Impact Factor
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ABSTRACT: Two natural piperamides (piperlonguminine and refrofractamide A) and their derivatives were synthesized and evaluated for inhibitory activity against histone deacetylases, as well as the HCT-116 human colon cancer cell line. The preliminary structure activity relationship was discussed. Compounds featuring a hydroxamic acid moiety exhibited moderate HDAC activity and in vitro cytotoxicity.
Bioorganic & medicinal chemistry letters 08/2011; 21(16):4844-6. · 2.65 Impact Factor
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Xiao-Peng He,
Qiong Deng,
Li-Xin Gao,
Cui Li,
Wei Zhang, Yu-Bo Zhou,
Yun Tang,
Xiao-Xin Shi,
Juan Xie,
Jia Li,
Guo-Rong Chen,
Kaixian Chen
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ABSTRACT: Protein tyrosine phosphatases (PTPs) are well-validated therapeutic targets for many human major diseases. The development of their potent inhibitors has therefore become a main focus of both academia and the pharmaceutical industry. We report herein a facile strategy toward the fabrication of new and competent PTP inhibitor entities by simply 'clicking' alkynyl amino acids onto diverse azido sugar templates. Triazolyl glucosyl, galactosyl, and mannosyl serine and threonine derivatives were efficiently synthesized via click reaction, which were then identified as potent CDC25B and PTP1B inhibitors selective over a panel of homologous PTPs tested. Their inhibitory activity and selectivity were found to largely lie on the structurally and configurationally diversified monosaccharide moieties whereon serinyl and threoninyl residues were introduced. In addition, MTT assay revealed the triazole-connected sugar-amino acid hybrids may also inhibit the growth of several human cancer cell lines including A549, Hela, and especially HCT-116. On the basis of such compelling evidence, we consider that this compound series could furnish promising chemical entities serving as new CDC25B and PTP1B inhibitors with potential cellular activity. Furthermore, the 'click' strategy starting from easily accessible and biocompatible amino acids and sugar templates would allow the modular fabrication of a rich library of new PTP inhibitors efficaciously and productively.
Bioorganic & medicinal chemistry 07/2011; 19(13):3892-900. · 2.82 Impact Factor
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ABSTRACT: Six new (rubiyunnanins C-H, 1-6) and five known (7-11) cyclic hexapeptides were isolated from the roots of Rubiayunnanensis (Franch.) Diels. The structures and stereochemistry of 1-6 were established by extensive spectroscopic analyses and chemical methods. All compounds (1-11) not only exhibited cytotoxic activities against a panel of eleven cancer cell lines with IC₅₀ values ranging from 0.001 to 56.24 μM, but also exerted inhibitory activities against nitric oxide (NO) production in LPS and IFN-γ-induced RAW 264.7 murine macrophages with IC₅₀ values ranging from 0.05 to 12.68 μM. Furthermore, this is the first time it is being reported that compounds 2 and 7-10 significantly inhibited TNF-α-induced NF-κB activation in HEK-293-NF-κB luciferase stable cells with IC₅₀ values of 35.07, 0.03, 1.69, 12.64 and 1.18 μM, respectively.
Bioorganic & medicinal chemistry 10/2010; 18(23):8226-34. · 2.82 Impact Factor
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ABSTRACT: To discover novel cell division cycle 25 (CDC25) B inhibitors and elucidate the mechanisms of inhibition in cancer cells.
Cell growth inhibition was detected by MTT assay, the cell cycle was analyzed by flow cytometry, and protein expression and phosphorylation was examined by Western blot analysis.
LGH00031 inhibited CDC25B irreversibly in vitro in a dose-dependent manner, and impaired the proliferation of tumor cell lines. In synchronized HeLa cells, LGH00031 delayed the cell cycle progression at the G(2)/M phase. LGH00031 increased cyclin-dependent kinase 1 (CDK1) tyrosine 15 phosphorylation and cyclin B1 protein level. The activity of LGH00031 against CDC25B in vitro relied on the existence of 1,4-dithiothreitol (DTT) or dihydrolipoic acid and oxygen. The oxygen free radical scavenger catalase and superoxide dismutase reduced the inactivation of CDC25 by LGH00031, confirming that reactive oxygen species (ROS) mediate the inactivation process in vitro. LGH00031 accelerated cellular ROS production in a dose-dependent manner, and N-acetyl cysteine (NAC) markedly decreased the ROS production induced by LGH00031. Correspondingly, the LGH00031-induced decrease in cell viability and cell cycle arrest, cyclin B1 protein level, and phosphorylation of CDK1 tyrosine 15 were also rescued by NAC that decreased ROS production.
The activity of LGH00031 at the molecular and cellular level is mediated by ROS.
Acta Pharmacologica Sinica 10/2009; 30(9):1359-68. · 1.95 Impact Factor
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ABSTRACT: In the present study we describe a novel secreted protein, named C12ORF39 (chromosome 12 open-reading framework 39), which contains a typical amidation/proteolytic processing signal (Gly-Arg-Arg motif). Interestingly, C12ORF39 protein is not hydrolysed, but is a full-length protein without signal peptides. Western blotting indicated that c-Myc-tagged C12ORF39 is secreted into culture medium in transfected HeLa cells. Quantitative RT-PCR (reverse transcription-PCR) analysis revealed that c12orf39 is mainly expressed in placenta and brain. Immunohistochemistry on formalin-fixed paraffin-embedded human term placenta using a rabbit antibody against human C12ORF39 demonstrated that the protein was localized extracellularly, surrounding the trophoblastic cells. In addition, C12ORF39 secretion could be blocked by brefeldin A, suggesting that the secretion of C12ORF39 is dependent on the Golgi apparatus. Furthermore, laser-scanning confocal microscopy also confirmed that the C12ORF39 protein co-localized with the Golgi apparatus. Taken together, although C12ORF39 is not a secreted small peptide, it can also be secreted to play a role in the biological functions of the placenta.
Bioscience Reports 03/2009; 30(1):1-10. · 2.38 Impact Factor
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ABSTRACT: Cell division cycle 25 (CDC25) phosphatases have recently been considered as potential targets for the development of new cancer therapeutic agents. We aimed to discover novel CDC25B inhibitors in the present study.
A molecular level high-throughput screening (HTS) assay was set up to screen a set of 48000 pure compounds.
HTS, whose average Z' factor is 0.55, was finished and LGH00045, a mixed-type CDC25B inhibitor with a novel structure and relative selectivity for protein tyrosine phosphatases, was identified. Furthermore, LGH00045 impaired the proliferation of tumor cells and increased cyclin-dependent kinase 1 inhibitory tyrosine phosphorylation. In synchronized HeLa cells, LGH00045 delayed cell cycle progression at the G2-M transition.
LGH00045, a novel CDC25B inhibitor identified through HTS, showed good inhibition on the proliferation of tumor cells and affected the cell cycle progression, which makes it a good hit for further structure modification.
Acta Pharmacologica Sinica 11/2008; 29(10):1268-74. · 1.95 Impact Factor
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ABSTRACT: Aim: Cell division cycle 25 (CDC25) phosphatases have recently been considered as potential targets for the development of new cancer therapeutic agents. We aimed to discover novel CDC25B inhibitors in the present study. Methods: A molecular level high-throughput screening (HTS) assay was set up to screen a set of 48000 pure compounds. Results: HTS, whose average Z′ factor is 0.55, was finished and LGH00045, a mixed-type CDC25B inhibitor with a novel structure and relative selectivity for protein tyrosine phosphatases, was identified. Furthermore, LGH00045 impaired the proliferation of tumor cells and increased cyclin-dependent kinase 1 inhibitory tyrosine phosphorylation. In synchronized HeLa cells, LGH00045 delayed cell cycle progression at the G2–M transition. Conclusion: LGH00045, a novel CDC25B inhibitor identified through HTS, showed good inhibition on the proliferation of tumor cells and affected the cell cycle progression, which makes it a good hit for further structure modification.
Acta Pharmacologica Sinica 10/2008; 29(10):1268 - 1274. · 1.95 Impact Factor
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ABSTRACT: We describe a novel secreted protein, named hOLFML1 (human olfactomedin-like protein 1), with an olfectamine domain in its C-terminus, mainly expressed in the small intestine, liver, lung and heart. Immunohistochemical staining on human small intestine indicated that the protein localizes preferentially in the intestinal villi. Interestingly, ectopic hOLFML1 promoted proliferation of HeLa cells and increased the percentage of cells in S phase. In contrast, knock down of hOLFML1 protein expression by siRNA inhibited cell proliferation and delayed the entry of cells into S phase. Our data also revealed that hOLFML1 is N-glycosylated and its secretion is triggered by serum. Taken together, these findings suggest that hOLFML1 may play a significant role in the regulation of cell proliferation in vitro.
FEBS Letters 09/2008; 582(21-22):3185-92. · 3.54 Impact Factor
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ABSTRACT: This study reported that all three human BolA proteins (hBolA1, hBolA2, and hBolA3) are novel non-classical secreted proteins identified with bioinformatics and molecular biology experiments. The three BolA fusion proteins with c-Myc tag could be secreted into the culture medium of the transfected Cos-7 cells, although they could not be colocalized with Golgi apparatus. And the secretion of three BolA proteins could not be inhibited after BFA treatment. Furthermore, the secretion was not dependent on its predicted signal peptide. All the experiment results suggested that the secretion was a non-classical export. Phylogenetic analysis showed that the human BolAs belong to three different groups with functional divergence of BolA subfamily, where the different helix-turn-helix motif among hBolA1, hBolA2, and hBolA3 could be responsible for their functional divergence. Our data provided a basis for functional studies of BolA protein family.
Molecular and Cellular Biochemistry 07/2008; 317(1-2):61-8. · 2.06 Impact Factor
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ABSTRACT: Here we reported a novel human secreted protein named as hZG16, with a Jacalin domain. Evolution analysis through comparing with the orthologs of other organisms suggested that ZG16 is a conserved gene under the purifying selection (d(N)/d(s)<1) in the evolution. Interestingly, Northern and dot blot analyses showed that hZG16 were highly expressed in adult liver, not in fetal liver, and moderately in gut, including jejunum, ileum, and colon, in which the tissue expression pattern of hZG16 was significantly dissimilar to that of mouse and rat orthologs that were uniquely expressed in spleen and pancreas, respectively. Unexpectedly, hZG16 was markedly down-regulated in hepatocellular carcinoma (HCC) as indicated by RT-PCR, Northern blot analysis and immunohistochemistry staining. However, the tunicamicin treatment and pulse-chase experiments showed that hZG16 protein had a similar molecular function with rZG16 that take part in glycoproteins' secretion in a bus mode.
Biochemical and Biophysical Research Communications 04/2007; 355(3):679-86. · 2.48 Impact Factor
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ABSTRACT: BTB/POZ protein family plays a key role in many biological processes both in Drosophila and vertebrates through regulating the transcriptional activities of some downstream genes. Here, we obtained a novel member of human BTB/POZ protein family, named as ZBTB34 (Zinc finger and BTB domain containing 34), which encodes 504 amino acid residues with a BTB/POZ domain at its N-terminus that is similar to the same domain of other known transcription regulators. RT-PCR analysis indicated that ZBTB34 was expressed ubiquitously in most adult human tissues, and whilst immunofluorescence assays showed that ZBTB34 was mainly localized to nucleus. Interestingly, the reporter assay in mammalian cells suggested that ZBTB34 might function as a transcriptional repressor. This present work as the first report about the functional exploration of the novel ZBTB34 gene would be contributed to profound understanding of the transcriptional regulation via BTB/POZ protein family.
Molecular and Cellular Biochemistry 11/2006; 290(1-2):159-67. · 2.06 Impact Factor
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ABSTRACT: Secreted proteins play important roles in many crucial biological processes, and can be new agents or targets for drug therapies. Here, we report on the isolation and characterization of a novel human non-classical secreted protein which is encoded by the hypothetical gene C19orf24 (chromosome 19 open reading frame 24). It has no signal peptide, but can still secrete extracellularly despite the presence of the inhibitor brefeldin A (BFA), proving its non-classical secreted protein status. Via subcellular localization using C19orf24 in vivo and transfected pEYFP-Golgi plasmid in Hela cells, C19orf24 was shown not to co-localize in the Golgi apparatus, which suggested that it secretes via a new and unknown pathway. Deglycosylation analysis with PNGase F verified that it has no N-glycosylation modification sites. Via the reverse transcription-PCR method, it was found to be expressed only in the human liver, and preferentially in normal tissue. In addition, C19orf24 was shown to be a recently evolved gene, found only in Homo sapiens and Pan troglodytes. By calculating its synonymous and non-synonymous substitution rate (d (S)/d (N)), we found that it experienced a purifying selection, which suggests that C19orf24 may have a special, irreplaceable biological function in the human organism.
Cellular & Molecular Biology Letters 02/2006; 11(2):161-70. · 1.50 Impact Factor
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ABSTRACT: To search for human novel secreted proteins and study their biological functions, using bioinformatical tools and experimental approaches, a novel secreted protein, human hMGRAP (Human Multiple Glutamine Repeat Acidic Protein) was obtained. hMGRAP consists of six coding exons spanning 1547bp of genomic DNA on the human chromosome 7q22.1, which encodes a protein with 248 amino acids. hMGRAP is rich of glutamic acid repeated sequence and the PI is 4.6. The coding sequence of hMGRAP was cloned by PCR method from the cDNA pool composed of nine human tissues. Western blot showed that hMGRAP protein was massively secreted out from the transiently transfected Cos-7 cells. RT-PCR result indicated hMGRAP mRNA was abundantly expressed in testis. In summary, a novel human gene encoding a secreted protein hMGRAP has been screened and cloned, and its biological function may specifically relate to its repeated glutamic acid sequence.
Hereditas (Beijing) 02/2005; 27(1):7-13.
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ABSTRACT: The present study reported the isolation and characterization of a novel human secreted protein, named as hPAP21 (human protease-associated domain-containing protein, 21 kDa), encoded by the hypothetical gene chromosome 2 open reading frame 7 (C2orf7) that contains signal peptide in its N-terminus, without transmembrane domain, except for PA domain in its middle. Western blotting assay indicated that the c-Myc tagged hPAP21 could be secreted into culture medium in the transfected Chinese hamster ovary cells. However, the molecular weights, whatever intracellular (28 kDa) or extracellular (30 kDa) forms, are larger than that of the prediction. To define whether the glycosylation was important process for its secretion, endoglycosidase H (Endo H) and PNGase F (PNG F) were employed to evaluate the effect of glycosylation types on secretion of hPAP21. Interestingly, the extracellular forms were primarily sensitive to PNG F, not Endo H, implying that complex N-glycosylation could be required for the secretion of hPAP21. Furthermore, N-glycosylation of Asn171 was confirmed as potential crucial process for the secretory protein via site-directed mutagenesis assay. All data will be contributed to the understanding of molecular functions of hPAP21.
FEBS Letters 11/2004; 576(3):401-7. · 3.54 Impact Factor
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Tetrahedron Letters 52(8):894-898. · 2.68 Impact Factor
